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Postgres FD Implementation
Commit 7bcc6d98 authored by Tom Lane's avatar Tom Lane
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Replace regular expression package with Henry Spencer's latest version 

(extracted from Tcl 8.4.1 release, as Henry still hasn't got round to
making it a separate library).  This solves a performance problem for
multibyte, as well as upgrading our regexp support to match recent Tcl
and nearly match recent Perl.
parent 32c3db0f
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doc/src/sgml/func.sgml
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<!-- <!--
$Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.136 2003/01/23 23:38:51 petere Exp $ $Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.137 2003/02/05 17:41:32 tgl Exp $
PostgreSQL documentation PostgreSQL documentation
--> -->
...@@ -424,7 +424,7 @@ PostgreSQL documentation ...@@ -424,7 +424,7 @@ PostgreSQL documentation
<row> <row>
<entry> <literal>&amp;</literal> </entry> <entry> <literal>&amp;</literal> </entry>
<entry>binary AND</entry> <entry>binary AND</entry>
<entry>91 & 15</entry> <entry>91 &amp; 15</entry>
<entry>11</entry> <entry>11</entry>
</row> </row>
...@@ -471,7 +471,7 @@ PostgreSQL documentation ...@@ -471,7 +471,7 @@ PostgreSQL documentation
The <quote>binary</quote> operators are also available for the bit The <quote>binary</quote> operators are also available for the bit
string types <type>BIT</type> and <type>BIT VARYING</type>, as string types <type>BIT</type> and <type>BIT VARYING</type>, as
shown in <xref linkend="functions-math-bit-table">. shown in <xref linkend="functions-math-bit-table">.
Bit string arguments to <literal>&</literal>, <literal>|</literal>, Bit string arguments to <literal>&amp;</literal>, <literal>|</literal>,
and <literal>#</literal> must be of equal length. When bit and <literal>#</literal> must be of equal length. When bit
shifting, the original length of the string is preserved, as shown shifting, the original length of the string is preserved, as shown
in the table. in the table.
...@@ -490,7 +490,7 @@ PostgreSQL documentation ...@@ -490,7 +490,7 @@ PostgreSQL documentation
<tbody> <tbody>
<row> <row>
<entry>B'10001' & B'01101'</entry> <entry>B'10001' &amp; B'01101'</entry>
<entry>00001</entry> <entry>00001</entry>
</row> </row>
<row> <row>
...@@ -2629,7 +2629,7 @@ SUBSTRING('foobar' FROM '#"o_b#"%' FOR '#') <lineannotation>NULL</lineannotat ...@@ -2629,7 +2629,7 @@ SUBSTRING('foobar' FROM '#"o_b#"%' FOR '#') <lineannotation>NULL</lineannotat
one whose left parenthesis comes first) is one whose left parenthesis comes first) is
returned. You can always put parentheses around the whole expression returned. You can always put parentheses around the whole expression
if you want to use parentheses within it without triggering this if you want to use parentheses within it without triggering this
exception. exception. Also see the non-capturing parentheses described below.
</para> </para>
<para> <para>
...@@ -2640,110 +2640,319 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation> ...@@ -2640,110 +2640,319 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation>
</programlisting> </programlisting>
</para> </para>
<!-- derived from the re_format.7 man page -->
<para> <para>
Regular expressions (<acronym>RE</acronym>s), as defined in <productname>PostgreSQL</productname>'s regular expressions are implemented
<acronym>POSIX</acronym> using a package written by Henry Spencer. Much of
1003.2, come in two forms: modern <acronym>RE</acronym>s (roughly those of the description of regular expressions below is copied verbatim from his
<command>egrep</command>; 1003.2 calls these manual entry.
<quote>extended</quote> <acronym>RE</acronym>s) and obsolete <acronym>RE</acronym>s (roughly those of
<command>ed</command>; 1003.2 <quote>basic</quote> <acronym>RE</acronym>s).
<productname>PostgreSQL</productname> implements the modern form.
</para> </para>
<!-- derived from the re_syntax.n man page -->
<sect3 id="posix-syntax-details">
<title>Regular Expression Details</title>
<para> <para>
A (modern) RE is one or more non-empty Regular expressions (<acronym>RE</acronym>s), as defined in
<acronym>POSIX</acronym> 1003.2, come in two forms:
<firstterm>extended</> <acronym>RE</acronym>s or <acronym>ERE</>s
(roughly those of <command>egrep</command>), and
<firstterm>basic</> <acronym>RE</acronym>s or <acronym>BRE</>s
(roughly those of <command>ed</command>).
<productname>PostgreSQL</productname> supports both forms, and
also implements some extensions
that are not in the POSIX standard, but have become widely used anyway
due to their availability in programming languages such as Perl and Tcl.
<acronym>RE</acronym>s using these non-POSIX extensions are called
<firstterm>advanced</> <acronym>RE</acronym>s or <acronym>ARE</>s
in this documentation. We first describe the ERE/ARE flavor and then
mention the restrictions of the BRE form.
</para>
<para>
A regular expression is defined as one or more
<firstterm>branches</firstterm>, separated by <firstterm>branches</firstterm>, separated by
<literal>|</literal>. It matches anything that matches one of the <literal>|</literal>. It matches anything that matches one of the
branches. branches.
</para> </para>
<para> <para>
A branch is one or more <firstterm>pieces</firstterm>, A branch is zero or more <firstterm>quantified atoms</> or
concatenated. It matches a match for the first, followed by a <firstterm>constraints</>, concatenated.
match for the second, etc. It matches a match for the first, followed by a match for the second, etc;
an empty branch matches the empty string.
</para>
<para>
A quantified atom is an <firstterm>atom</> possibly followed
by a single <firstterm>quantifier</>.
Without a quantifier, it matches a match for the atom.
With a quantifier, it can match some number of matches of the atom.
An <firstterm>atom</firstterm> can be any of the possibilities
shown in <xref linkend="posix-atoms-table">.
The possible quantifiers and their meanings are shown in
<xref linkend="posix-quantifiers-table">.
</para> </para>
<para> <para>
A piece is an <firstterm>atom</firstterm> possibly followed by a A <firstterm>constraint</> matches an empty string, but matches only when
single <literal>*</literal>, <literal>+</literal>, specific conditions are met. A constraint can be used where an atom
<literal>?</literal>, or <firstterm>bound</firstterm>. An atom could be used, except it may not be followed by a quantifier.
followed by <literal>*</literal> matches a sequence of 0 or more The simple constraints are shown in
matches of the atom. An atom followed by <literal>+</literal> <xref linkend="posix-constraints-table">;
matches a sequence of 1 or more matches of the atom. An atom some more constraints are described later.
followed by <literal>?</literal> matches a sequence of 0 or 1
matches of the atom.
</para> </para>
<table id="posix-atoms-table">
<title>Regular Expression Atoms</title>
<tgroup cols="2">
<thead>
<row>
<entry>Atom</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>(</><replaceable>re</><literal>)</> </entry>
<entry> (where <replaceable>re</> is any regular expression)
matches a match for
<replaceable>re</>, with the match noted for possible reporting </entry>
</row>
<row>
<entry> <literal>(?:</><replaceable>re</><literal>)</> </entry>
<entry> as above, but the match is not noted for reporting
(a <quote>non-capturing</> set of parentheses)
(AREs only) </entry>
</row>
<row>
<entry> <literal>.</> </entry>
<entry> matches any single character </entry>
</row>
<row>
<entry> <literal>[</><replaceable>chars</><literal>]</> </entry>
<entry> a <firstterm>bracket expression</>,
matching any one of the <replaceable>chars</> (see
<xref linkend="posix-bracket-expressions"> for more detail) </entry>
</row>
<row>
<entry> <literal>\</><replaceable>k</> </entry>
<entry> (where <replaceable>k</> is a non-alphanumeric character)
matches that character taken as an ordinary character,
e.g. <literal>\\</> matches a backslash character </entry>
</row>
<row>
<entry> <literal>\</><replaceable>c</> </entry>
<entry> where <replaceable>c</> is alphanumeric
(possibly followed by other characters)
is an <firstterm>escape</>, see <xref linkend="posix-escape-sequences">
(AREs only; in EREs and BREs, this matches <replaceable>c</>) </entry>
</row>
<row>
<entry> <literal>{</> </entry>
<entry> when followed by a character other than a digit,
matches the left-brace character <literal>{</>;
when followed by a digit, it is the beginning of a
<replaceable>bound</> (see below) </entry>
</row>
<row>
<entry> <replaceable>x</> </entry>
<entry> where <replaceable>x</> is a single character with no other
significance, matches that character </entry>
</row>
</tbody>
</tgroup>
</table>
<para> <para>
A <firstterm>bound</firstterm> is <literal>{</literal> followed by An RE may not end with <literal>\</>.
an unsigned decimal integer, possibly followed by
<literal>,</literal> possibly followed by another unsigned decimal
integer, always followed by <literal>}</literal>. The integers
must lie between 0 and <symbol>RE_DUP_MAX</symbol> (255)
inclusive, and if there are two of them, the first may not exceed
the second. An atom followed by a bound containing one integer
<replaceable>i</replaceable> and no comma matches a sequence of
exactly <replaceable>i</replaceable> matches of the atom. An atom
followed by a bound containing one integer
<replaceable>i</replaceable> and a comma matches a sequence of
<replaceable>i</replaceable> or more matches of the atom. An atom
followed by a bound containing two integers
<replaceable>i</replaceable> and <replaceable>j</replaceable>
matches a sequence of <replaceable>i</replaceable> through
<replaceable>j</replaceable> (inclusive) matches of the atom.
</para> </para>
<note> <note>
<para> <para>
A repetition operator (<literal>?</literal>, Remember that the backslash (<literal>\</literal>) already has a special
<literal>*</literal>, <literal>+</literal>, or bounds) cannot meaning in <productname>PostgreSQL</> string literals.
follow another repetition operator. A repetition operator cannot To write a pattern constant that contains a backslash,
you must write two backslashes in the query.
</para>
</note>
<table id="posix-quantifiers-table">
<title>Regular Expression Quantifiers</title>
<tgroup cols="2">
<thead>
<row>
<entry>Quantifier</entry>
<entry>Matches</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>*</> </entry>
<entry> a sequence of 0 or more matches of the atom </entry>
</row>
<row>
<entry> <literal>+</> </entry>
<entry> a sequence of 1 or more matches of the atom </entry>
</row>
<row>
<entry> <literal>?</> </entry>
<entry> a sequence of 0 or 1 matches of the atom </entry>
</row>
<row>
<entry> <literal>{</><replaceable>m</><literal>}</> </entry>
<entry> a sequence of exactly <replaceable>m</> matches of the atom </entry>
</row>
<row>
<entry> <literal>{</><replaceable>m</><literal>,}</> </entry>
<entry> a sequence of <replaceable>m</> or more matches of the atom </entry>
</row>
<row>
<entry>
<literal>{</><replaceable>m</><literal>,</><replaceable>n</><literal>}</> </entry>
<entry> a sequence of <replaceable>m</> through <replaceable>n</>
(inclusive) matches of the atom; <replaceable>m</> may not exceed
<replaceable>n</> </entry>
</row>
<row>
<entry> <literal>*?</> </entry>
<entry> non-greedy version of <literal>*</> </entry>
</row>
<row>
<entry> <literal>+?</> </entry>
<entry> non-greedy version of <literal>+</> </entry>
</row>
<row>
<entry> <literal>??</> </entry>
<entry> non-greedy version of <literal>?</> </entry>
</row>
<row>
<entry> <literal>{</><replaceable>m</><literal>}?</> </entry>
<entry> non-greedy version of <literal>{</><replaceable>m</><literal>}</> </entry>
</row>
<row>
<entry> <literal>{</><replaceable>m</><literal>,}?</> </entry>
<entry> non-greedy version of <literal>{</><replaceable>m</><literal>,}</> </entry>
</row>
<row>
<entry>
<literal>{</><replaceable>m</><literal>,</><replaceable>n</><literal>}?</> </entry>
<entry> non-greedy version of <literal>{</><replaceable>m</><literal>,</><replaceable>n</><literal>}</> </entry>
</row>
</tbody>
</tgroup>
</table>
<para>
The forms using <literal>{</><replaceable>...</><literal>}</>
are known as <firstterm>bound</>s.
The numbers <replaceable>m</> and <replaceable>n</> within a bound are
unsigned decimal integers with permissible values from 0 to 255 inclusive.
</para>
<para>
<firstterm>Non-greedy</> quantifiers (available in AREs only) match the
same possibilities as their corresponding normal (<firstterm>greedy</>)
counterparts, but prefer the smallest number rather than the largest
number of matches.
See <xref linkend="posix-matching-rules"> for more detail.
</para>
<note>
<para>
A quantifier cannot immediately follow another quantifier.
A quantifier cannot
begin an expression or subexpression or follow begin an expression or subexpression or follow
<literal>^</literal> or <literal>|</literal>. <literal>^</literal> or <literal>|</literal>.
</para> </para>
</note> </note>
<table id="posix-constraints-table">
<title>Regular Expression Constraints</title>
<tgroup cols="2">
<thead>
<row>
<entry>Constraint</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>^</> </entry>
<entry> matches at the beginning of the string </entry>
</row>
<row>
<entry> <literal>$</> </entry>
<entry> matches at the end of the string </entry>
</row>
<row>
<entry> <literal>(?=</><replaceable>re</><literal>)</> </entry>
<entry> <firstterm>positive lookahead</> matches at any point
where a substring matching <replaceable>re</> begins
(AREs only) </entry>
</row>
<row>
<entry> <literal>(?!</><replaceable>re</><literal>)</> </entry>
<entry> <firstterm>negative lookahead</> matches at any point
where no substring matching <replaceable>re</> begins
(AREs only) </entry>
</row>
</tbody>
</tgroup>
</table>
<para> <para>
An <firstterm>atom</firstterm> is a regular expression enclosed in Lookahead constraints may not contain <firstterm>back references</>
<literal>()</literal> (matching a match for the regular (see <xref linkend="posix-escape-sequences">),
expression), an empty set of <literal>()</literal> (matching the and all parentheses within them are considered non-capturing.
null string), a <firstterm>bracket expression</firstterm> (see
below), <literal>.</literal> (matching any single character),
<literal>^</literal> (matching the null string at the beginning of the
input string), <literal>$</literal> (matching the null string at the end
of the input string), a <literal>\</literal> followed by one of the
characters <literal>^.[$()|*+?{\</literal> (matching that
character taken as an ordinary character), a <literal>\</literal>
followed by any other character (matching that character taken as
an ordinary character, as if the <literal>\</literal> had not been
present), or a single character with no other significance
(matching that character). A <literal>{</literal> followed by a
character other than a digit is an ordinary character, not the
beginning of a bound. It is illegal to end an RE with
<literal>\</literal>.
</para>
<para>
Note that the backslash (<literal>\</literal>) already has a special
meaning in string
literals, so to write a pattern constant that contains a backslash
you must write two backslashes in the query.
</para> </para>
</sect3>
<sect3 id="posix-bracket-expressions">
<title>Bracket Expressions</title>
<para> <para>
A <firstterm>bracket expression</firstterm> is a list of A <firstterm>bracket expression</firstterm> is a list of
characters enclosed in <literal>[]</literal>. It normally matches characters enclosed in <literal>[]</literal>. It normally matches
any single character from the list (but see below). If the list any single character from the list (but see below). If the list
begins with <literal>^</literal>, it matches any single character begins with <literal>^</literal>, it matches any single character
(but see below) not from the rest of the list. If two characters <emphasis>not</> from the rest of the list.
If two characters
in the list are separated by <literal>-</literal>, this is in the list are separated by <literal>-</literal>, this is
shorthand for the full range of characters between those two shorthand for the full range of characters between those two
(inclusive) in the collating sequence, (inclusive) in the collating sequence,
e.g. <literal>[0-9]</literal> in <acronym>ASCII</acronym> matches e.g. <literal>[0-9]</literal> in <acronym>ASCII</acronym> matches
any decimal digit. It is illegal for two ranges to share an any decimal digit. It is illegal for two ranges to share an
endpoint, e.g. <literal>a-c-e</literal>. Ranges are very endpoint, e.g. <literal>a-c-e</literal>. Ranges are very
collating-sequence-dependent, and portable programs should avoid collating-sequence-dependent, so portable programs should avoid
relying on them. relying on them.
</para> </para>
...@@ -2754,11 +2963,13 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation> ...@@ -2754,11 +2963,13 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation>
character, or the second endpoint of a range. To use a literal character, or the second endpoint of a range. To use a literal
<literal>-</literal> as the first endpoint of a range, enclose it <literal>-</literal> as the first endpoint of a range, enclose it
in <literal>[.</literal> and <literal>.]</literal> to make it a in <literal>[.</literal> and <literal>.]</literal> to make it a
collating element (see below). With the exception of these and collating element (see below). With the exception of these characters,
some combinations using <literal>[</literal> (see next some combinations using <literal>[</literal>
paragraphs), all other special characters, including (see next paragraphs), and escapes (AREs only), all other special
<literal>\</literal>, lose their special significance within a characters lose their special significance within a bracket expression.
bracket expression. In particular, <literal>\</literal> is not special when following
ERE or BRE rules, though it is special (as introducing an escape)
in AREs.
</para> </para>
<para> <para>
...@@ -2775,6 +2986,13 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation> ...@@ -2775,6 +2986,13 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation>
<literal>chchcc</literal>. <literal>chchcc</literal>.
</para> </para>
<note>
<para>
<productname>PostgreSQL</> currently has no multi-character collating
elements. This information describes possible future behavior.
</para>
</note>
<para> <para>
Within a bracket expression, a collating element enclosed in Within a bracket expression, a collating element enclosed in
<literal>[=</literal> and <literal>=]</literal> is an equivalence <literal>[=</literal> and <literal>=]</literal> is an equivalence
...@@ -2809,76 +3027,732 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation> ...@@ -2809,76 +3027,732 @@ SUBSTRING('foobar' FROM 'o(.)b') <lineannotation>o</lineannotation>
<para> <para>
There are two special cases of bracket expressions: the bracket There are two special cases of bracket expressions: the bracket
expressions <literal>[[:&lt;:]]</literal> and expressions <literal>[[:&lt;:]]</literal> and
<literal>[[:>:]]</literal> match the null string at the beginning <literal>[[:&gt;:]]</literal> are constraints,
matching empty strings at the beginning
and end of a word respectively. A word is defined as a sequence and end of a word respectively. A word is defined as a sequence
of word characters which is neither preceded nor followed by word of word characters that is neither preceded nor followed by word
characters. A word character is an alnum character (as defined by characters. A word character is an <literal>alnum</> character (as
defined by
<citerefentry><refentrytitle>ctype</refentrytitle><manvolnum>3</manvolnum></citerefentry>) <citerefentry><refentrytitle>ctype</refentrytitle><manvolnum>3</manvolnum></citerefentry>)
or an underscore. This is an extension, compatible with but not or an underscore. This is an extension, compatible with but not
specified by <acronym>POSIX</acronym> 1003.2, and should be used with caution in specified by <acronym>POSIX</acronym> 1003.2, and should be used with
software intended to be portable to other systems. caution in software intended to be portable to other systems.
The constraint escapes described below are usually preferable (they
are no more standard, but are certainly easier to type).
</para>
</sect3>
<sect3 id="posix-escape-sequences">
<title>Regular Expression Escapes</title>
<para>
<firstterm>Escapes</> are special sequences beginning with <literal>\</>
followed by an alphanumeric character. Escapes come in several varieties:
character entry, class shorthands, constraint escapes, and back references.
A <literal>\</> followed by an alphanumeric character but not constituting
a valid escape is illegal in AREs.
In EREs, there are no escapes: outside a bracket expression,
a <literal>\</> followed by an alphanumeric character merely stands for
that character as an ordinary character, and inside a bracket expression,
<literal>\</> is an ordinary character.
(The latter is the one actual incompatibility between EREs and AREs.)
</para>
<para>
<firstterm>Character-entry escapes</> exist to make it easier to specify
non-printing and otherwise inconvenient characters in REs. They are
shown in <xref linkend="posix-character-entry-escapes-table">.
</para>
<para>
<firstterm>Class-shorthand escapes</> provide shorthands for certain
commonly-used character classes. They are
shown in <xref linkend="posix-class-shorthand-escapes-table">.
</para>
<para>
A <firstterm>constraint escape</> is a constraint,
matching the empty string if specific conditions are met,
written as an escape. They are
shown in <xref linkend="posix-constraint-escapes-table">.
</para>
<para>
A <firstterm>back reference</> (<literal>\</><replaceable>n</>) matches the
same string matched by the previous parenthesized subexpression specified
by the number <replaceable>n</>
(see <xref linkend="posix-constraint-backref-table">). For example,
<literal>([bc])\1</> matches <literal>bb</> or <literal>cc</>
but not <literal>bc</> or <literal>cb</>.
The subexpression must entirely precede the back reference in the RE.
Subexpressions are numbered in the order of their leading parentheses.
Non-capturing parentheses do not define subexpressions.
</para>
<note>
<para>
Keep in mind that an escape's leading <literal>\</> will need to be
doubled when entering the pattern as an SQL string constant.
</para>
</note>
<table id="posix-character-entry-escapes-table">
<title>Regular Expression Character-Entry Escapes</title>
<tgroup cols="2">
<thead>
<row>
<entry>Escape</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>\a</> </entry>
<entry> alert (bell) character, as in C </entry>
</row>
<row>
<entry> <literal>\b</> </entry>
<entry> backspace, as in C </entry>
</row>
<row>
<entry> <literal>\B</> </entry>
<entry> synonym for <literal>\</> to help reduce the need for backslash
doubling </entry>
</row>
<row>
<entry> <literal>\c</><replaceable>X</> </entry>
<entry> (where <replaceable>X</> is any character) the character whose
low-order 5 bits are the same as those of
<replaceable>X</>, and whose other bits are all zero </entry>
</row>
<row>
<entry> <literal>\e</> </entry>
<entry> the character whose collating-sequence name
is <literal>ESC</>,
or failing that, the character with octal value 033 </entry>
</row>
<row>
<entry> <literal>\f</> </entry>
<entry> formfeed, as in C </entry>
</row>
<row>
<entry> <literal>\n</> </entry>
<entry> newline, as in C </entry>
</row>
<row>
<entry> <literal>\r</> </entry>
<entry> carriage return, as in C </entry>
</row>
<row>
<entry> <literal>\t</> </entry>
<entry> horizontal tab, as in C </entry>
</row>
<row>
<entry> <literal>\u</><replaceable>wxyz</> </entry>
<entry> (where <replaceable>wxyz</> is exactly four hexadecimal digits)
the Unicode character <literal>U+</><replaceable>wxyz</>
in the local byte ordering </entry>
</row>
<row>
<entry> <literal>\U</><replaceable>stuvwxyz</> </entry>
<entry> (where <replaceable>stuvwxyz</> is exactly eight hexadecimal
digits)
reserved for a somewhat-hypothetical Unicode extension to 32 bits
</entry>
</row>
<row>
<entry> <literal>\v</> </entry>
<entry> vertical tab, as in C </entry>
</row>
<row>
<entry> <literal>\x</><replaceable>hhh</> </entry>
<entry> (where <replaceable>hhh</> is any sequence of hexadecimal
digits)
the character whose hexadecimal value is
<literal>0x</><replaceable>hhh</>
(a single character no matter how many hexadecimal digits are used)
</entry>
</row>
<row>
<entry> <literal>\0</> </entry>
<entry> the character whose value is <literal>0</> </entry>
</row>
<row>
<entry> <literal>\</><replaceable>xy</> </entry>
<entry> (where <replaceable>xy</> is exactly two octal digits,
and is not a <firstterm>back reference</>)
the character whose octal value is
<literal>0</><replaceable>xy</> </entry>
</row>
<row>
<entry> <literal>\</><replaceable>xyz</> </entry>
<entry> (where <replaceable>xyz</> is exactly three octal digits,
and is not a <firstterm>back reference</>)
the character whose octal value is
<literal>0</><replaceable>xyz</> </entry>
</row>
</tbody>
</tgroup>
</table>
<para>
Hexadecimal digits are <literal>0</>-<literal>9</>,
<literal>a</>-<literal>f</>, and <literal>A</>-<literal>F</>.
Octal digits are <literal>0</>-<literal>7</>.
</para> </para>
<para> <para>
In the event that an RE could match more than one substring of a The character-entry escapes are always taken as ordinary characters.
given string, the RE matches the one starting earliest in the For example, <literal>\135</> is <literal>]</> in ASCII, but
string. If the RE could match more than one substring starting at <literal>\135</> does not terminate a bracket expression.
that point, it matches the longest. Subexpressions also match the
longest possible substrings, subject to the constraint that the
whole match be as long as possible, with subexpressions starting
earlier in the RE taking priority over ones starting later. Note
that higher-level subexpressions thus take priority over their
lower-level component subexpressions.
</para> </para>
<table id="posix-class-shorthand-escapes-table">
<title>Regular Expression Class-Shorthand Escapes</title>
<tgroup cols="2">
<thead>
<row>
<entry>Escape</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>\d</> </entry>
<entry> <literal>[[:digit:]]</> </entry>
</row>
<row>
<entry> <literal>\s</> </entry>
<entry> <literal>[[:space:]]</> </entry>
</row>
<row>
<entry> <literal>\w</> </entry>
<entry> <literal>[[:alnum:]_]</>
(note underscore is included) </entry>
</row>
<row>
<entry> <literal>\D</> </entry>
<entry> <literal>[^[:digit:]]</> </entry>
</row>
<row>
<entry> <literal>\S</> </entry>
<entry> <literal>[^[:space:]]</> </entry>
</row>
<row>
<entry> <literal>\W</> </entry>
<entry> <literal>[^[:alnum:]_]</>
(note underscore is included) </entry>
</row>
</tbody>
</tgroup>
</table>
<para> <para>
Match lengths are measured in characters, not collating Within bracket expressions, <literal>\d</>, <literal>\s</>,
elements. A null string is considered longer than no match at and <literal>\w</> lose their outer brackets,
all. For example, <literal>bb*</literal> matches the three middle and <literal>\D</>, <literal>\S</>, and <literal>\W</> are illegal.
characters of <literal>abbbc</literal>, (So, for example, <literal>[a-c\d]</> is equivalent to
<literal>(wee|week)(knights|nights)</literal> matches all ten <literal>[a-c[:digit:]]</>.
characters of <literal>weeknights</literal>, when Also, <literal>[a-c\D]</>, which is equivalent to
<literal>(.*).*</literal> is matched against <literal>[a-c^[:digit:]]</>, is illegal.)
<literal>abc</literal> the parenthesized subexpression matches all
three characters, and when <literal>(a*)*</literal> is matched
against <literal>bc</literal> both the whole RE and the
parenthesized subexpression match the null string.
</para> </para>
<table id="posix-constraint-escapes-table">
<title>Regular Expression Constraint Escapes</title>
<tgroup cols="2">
<thead>
<row>
<entry>Escape</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>\A</> </entry>
<entry> matches only at the beginning of the string
(see <xref linkend="posix-matching-rules"> for how this differs from
<literal>^</>) </entry>
</row>
<row>
<entry> <literal>\m</> </entry>
<entry> matches only at the beginning of a word </entry>
</row>
<row>
<entry> <literal>\M</> </entry>
<entry> matches only at the end of a word </entry>
</row>
<row>
<entry> <literal>\y</> </entry>
<entry> matches only at the beginning or end of a word </entry>
</row>
<row>
<entry> <literal>\Y</> </entry>
<entry> matches only at a point that is not the beginning or end of a
word </entry>
</row>
<row>
<entry> <literal>\Z</> </entry>
<entry> matches only at the end of the string
(see <xref linkend="posix-matching-rules"> for how this differs from
<literal>$</>) </entry>
</row>
</tbody>
</tgroup>
</table>
<para>
A word is defined as in the specification of
<literal>[[:&lt;:]]</> and <literal>[[:&gt;:]]</> above.
Constraint escapes are illegal within bracket expressions.
</para>
<table id="posix-constraint-backref-table">
<title>Regular Expression Back References</title>
<tgroup cols="2">
<thead>
<row>
<entry>Escape</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>\</><replaceable>m</> </entry>
<entry> (where <replaceable>m</> is a nonzero digit)
a back reference to the <replaceable>m</>'th subexpression </entry>
</row>
<row>
<entry> <literal>\</><replaceable>mnn</> </entry>
<entry> (where <replaceable>m</> is a nonzero digit, and
<replaceable>nn</> is some more digits, and the decimal value
<replaceable>mnn</> is not greater than the number of closing capturing
parentheses seen so far)
a back reference to the <replaceable>mnn</>'th subexpression </entry>
</row>
</tbody>
</tgroup>
</table>
<note>
<para> <para>
If case-independent matching is specified, the effect is much as There is an inherent historical ambiguity between octal character-entry
if all case distinctions had vanished from the alphabet. When an escapes and back references, which is resolved by heuristics,
alphabetic that exists in multiple cases appears as an ordinary as hinted at above.
character outside a bracket expression, it is effectively A leading zero always indicates an octal escape.
A single non-zero digit, not followed by another digit,
is always taken as a back reference.
A multi-digit sequence not starting with a zero is taken as a back
reference if it comes after a suitable subexpression
(i.e. the number is in the legal range for a back reference),
and otherwise is taken as octal.
</para>
</note>
</sect3>
<sect3 id="posix-metasyntax">
<title>Regular Expression Metasyntax</title>
<para>
In addition to the main syntax described above, there are some special
forms and miscellaneous syntactic facilities available.
</para>
<para>
Normally the flavor of RE being used is specified by
application-dependent means.
However, this can be overridden by a <firstterm>director</>.
If an RE of any flavor begins with <literal>***:</>,
the rest of the RE is an ARE.
If an RE of any flavor begins with <literal>***=</>,
the rest of the RE is taken to be a literal string,
with all characters considered ordinary characters.
</para>
<para>
An ARE may begin with <firstterm>embedded options</>:
a sequence <literal>(?</><replaceable>xyz</><literal>)</>
(where <replaceable>xyz</> is one or more alphabetic characters)
specifies options affecting the rest of the RE.
These supplement, and can override,
any options specified externally.
The available option letters are
shown in <xref linkend="posix-embedded-options-table">.
</para>
<table id="posix-embedded-options-table">
<title>ARE Embedded-Option Letters</title>
<tgroup cols="2">
<thead>
<row>
<entry>Option</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> <literal>b</> </entry>
<entry> rest of RE is a BRE </entry>
</row>
<row>
<entry> <literal>c</> </entry>
<entry> case-sensitive matching (usual default) </entry>
</row>
<row>
<entry> <literal>e</> </entry>
<entry> rest of RE is an ERE </entry>
</row>
<row>
<entry> <literal>i</> </entry>
<entry> case-insensitive matching (see
<xref linkend="posix-matching-rules">) </entry>
</row>
<row>
<entry> <literal>m</> </entry>
<entry> historical synonym for <literal>n</> </entry>
</row>
<row>
<entry> <literal>n</> </entry>
<entry> newline-sensitive matching (see
<xref linkend="posix-matching-rules">) </entry>
</row>
<row>
<entry> <literal>p</> </entry>
<entry> partial newline-sensitive matching (see
<xref linkend="posix-matching-rules">) </entry>
</row>
<row>
<entry> <literal>q</> </entry>
<entry> rest of RE is a literal (<quote>quoted</>) string, all ordinary
characters </entry>
</row>
<row>
<entry> <literal>s</> </entry>
<entry> non-newline-sensitive matching (usual default) </entry>
</row>
<row>
<entry> <literal>t</> </entry>
<entry> tight syntax (usual default; see below) </entry>
</row>
<row>
<entry> <literal>w</> </entry>
<entry> inverse partial newline-sensitive (<quote>weird</>) matching
(see <xref linkend="posix-matching-rules">) </entry>
</row>
<row>
<entry> <literal>x</> </entry>
<entry> expanded syntax (see below) </entry>
</row>
</tbody>
</tgroup>
</table>
<para>
Embedded options take effect at the <literal>)</> terminating the sequence.
They are available only at the start of an ARE,
and may not be used later within it.
</para>
<para>
In addition to the usual (<firstterm>tight</>) RE syntax, in which all
characters are significant, there is an <firstterm>expanded</> syntax,
available by specifying the embedded <literal>x</> option.
In the expanded syntax,
white-space characters in the RE are ignored, as are
all characters between a <literal>#</>
and the following newline (or the end of the RE). This
permits paragraphing and commenting a complex RE.
There are three exceptions to that basic rule:
<itemizedlist>
<listitem>
<para>
a white-space character or <literal>#</> preceded by <literal>\</> is
retained
</para>
</listitem>
<listitem>
<para>
white space or <literal>#</> within a bracket expression is retained
</para>
</listitem>
<listitem>
<para>
white space and comments are illegal within multi-character symbols,
like the ARE <literal>(?:</> or the BRE <literal>\(</>
</para>
</listitem>
</itemizedlist>
Expanded-syntax white-space characters are blank, tab, newline, and
any character that belongs to the <replaceable>space</> character class.
</para>
<para>
Finally, in an ARE, outside bracket expressions, the sequence
<literal>(?#</><replaceable>ttt</><literal>)</>
(where <replaceable>ttt</> is any text not containing a <literal>)</>)
is a comment, completely ignored.
Again, this is not allowed between the characters of
multi-character symbols, like <literal>(?:</>.
Such comments are more a historical artifact than a useful facility,
and their use is deprecated; use the expanded syntax instead.
</para>
<para>
<emphasis>None</> of these metasyntax extensions is available if
an initial <literal>***=</> director
has specified that the user's input be treated as a literal string
rather than as an RE.
</para>
</sect3>
<sect3 id="posix-matching-rules">
<title>Regular Expression Matching Rules</title>
<para>
In the event that an RE could match more than one substring of a given
string, the RE matches the one starting earliest in the string.
If the RE could match more than one substring starting at that point,
its choice is determined by its <firstterm>preference</>:
either the longest substring, or the shortest.
</para>
<para>
Most atoms, and all constraints, have no preference.
A parenthesized RE has the same preference (possibly none) as the RE.
A quantified atom with quantifier
<literal>{</><replaceable>m</><literal>}</>
or
<literal>{</><replaceable>m</><literal>}?</>
has the same preference (possibly none) as the atom itself.
A quantified atom with other normal quantifiers (including
<literal>{</><replaceable>m</><literal>,</><replaceable>n</><literal>}</>
with <replaceable>m</> equal to <replaceable>n</>)
prefers longest match.
A quantified atom with other non-greedy quantifiers (including
<literal>{</><replaceable>m</><literal>,</><replaceable>n</><literal>}?</>
with <replaceable>m</> equal to <replaceable>n</>)
prefers shortest match.
A branch has the same preference as the first quantified atom in it
which has a preference.
An RE consisting of two or more branches connected by the
<literal>|</> operator prefers longest match.
</para>
<para>
Subject to the constraints imposed by the rules for matching the whole RE,
subexpressions also match the longest or shortest possible substrings,
based on their preferences,
with subexpressions starting earlier in the RE taking priority over
ones starting later.
Note that outer subexpressions thus take priority over
their component subexpressions.
</para>
<para>
The quantifiers <literal>{1,1}</> and <literal>{1,1}?</>
can be used to force longest and shortest preference, respectively,
on a subexpression or a whole RE.
</para>
<para>
Match lengths are measured in characters, not collating elements.
An empty string is considered longer than no match at all.
For example:
<literal>bb*</>
matches the three middle characters of <literal>abbbc</>;
<literal>(week|wee)(night|knights)</>
matches all ten characters of <literal>weeknights</>;
when <literal>(.*).*</>
is matched against <literal>abc</> the parenthesized subexpression
matches all three characters; and when
<literal>(a*)*</> is matched against <literal>bc</>
both the whole RE and the parenthesized
subexpression match an empty string.
</para>
<para>
If case-independent matching is specified,
the effect is much as if all case distinctions had vanished from the
alphabet.
When an alphabetic that exists in multiple cases appears as an
ordinary character outside a bracket expression, it is effectively
transformed into a bracket expression containing both cases, transformed into a bracket expression containing both cases,
e.g. <literal>x</literal> becomes <literal>[xX]</literal>. When e.g. <literal>x</> becomes <literal>[xX]</>.
it appears inside a bracket expression, all case counterparts of When it appears inside a bracket expression, all case counterparts
it are added to the bracket expression, so that (e.g.) of it are added to the bracket expression, e.g.
<literal>[x]</literal> becomes <literal>[xX]</literal> and <literal>[x]</> becomes <literal>[xX]</>
<literal>[^x]</literal> becomes <literal>[^xX]</literal>. and <literal>[^x]</> becomes <literal>[^xX]</>.
</para> </para>
<para> <para>
There is no particular limit on the length of <acronym>RE</acronym>s, except insofar If newline-sensitive matching is specified, <literal>.</>
as memory is limited. Memory usage is approximately linear in RE and bracket expressions using <literal>^</>
size, and largely insensitive to RE complexity, except for bounded will never match the newline character
repetitions. Bounded repetitions are implemented by macro (so that matches will never cross newlines unless the RE
expansion, which is costly in time and space if counts are large explicitly arranges it)
or bounded repetitions are nested. An RE like, say, and <literal>^</>and <literal>$</>
<literal>((((a{1,100}){1,100}){1,100}){1,100}){1,100}</literal> will match the empty string after and before a newline
will (eventually) run almost any existing machine out of swap respectively, in addition to matching at beginning and end of string
space. respectively.
<footnote> But the ARE escapes <literal>\A</> and <literal>\Z</>
continue to match beginning or end of string <emphasis>only</>.
</para>
<para> <para>
This was written in 1994, mind you. The If partial newline-sensitive matching is specified,
numbers have probably changed, but the problem this affects <literal>.</> and bracket expressions
persists. as with newline-sensitive matching, but not <literal>^</>
and <literal>$</>.
</para> </para>
</footnote>
<para>
If inverse partial newline-sensitive matching is specified,
this affects <literal>^</> and <literal>$</>
as with newline-sensitive matching, but not <literal>.</>
and bracket expressions.
This isn't very useful but is provided for symmetry.
</para> </para>
<!-- end re_format.7 man page --> </sect3>
</sect2>
<sect3 id="posix-limits-compatibility">
<title>Limits and Compatibility</title>
<para>
No particular limit is imposed on the length of REs in this
implementation. However,
programs intended to be highly portable should not employ REs longer
than 256 bytes,
as a POSIX-compliant implementation can refuse to accept such REs.
</para>
<para>
The only feature of AREs that is actually incompatible with
POSIX EREs is that <literal>\</> does not lose its special
significance inside bracket expressions.
All other ARE features use syntax which is illegal or has
undefined or unspecified effects in POSIX EREs;
the <literal>***</> syntax of directors likewise is outside the POSIX
syntax for both BREs and EREs.
</para>
<para>
Many of the ARE extensions are borrowed from Perl, but some have
been changed to clean them up, and a few Perl extensions are not present.
Incompatibilities of note include <literal>\b</>, <literal>\B</>,
the lack of special treatment for a trailing newline,
the addition of complemented bracket expressions to the things
affected by newline-sensitive matching,
the restrictions on parentheses and back references in lookahead
constraints, and the longest/shortest-match (rather than first-match)
matching semantics.
</para>
<para>
Two significant incompatibilites exist between AREs and the ERE syntax
recognized by pre-7.4 releases of <productname>PostgreSQL</>:
<itemizedlist>
<listitem>
<para>
In AREs, <literal>\</> followed by an alphanumeric character is either
an escape or an error, while in previous releases, it was just another
way of writing the alphanumeric.
This should not be much of a problem because there was no reason to
write such a sequence in earlier releases.
</para>
</listitem>
<listitem>
<para>
In AREs, <literal>\</> remains a special character within
<literal>[]</>, so a literal <literal>\</> within a bracket
expression must be written <literal>\\</>.
</para>
</listitem>
</itemizedlist>
</para>
</sect3>
<sect3 id="posix-basic-regexes">
<title>Basic Regular Expressions</title>
<para>
BREs differ from EREs in several respects.
<literal>|</>, <literal>+</>, and <literal>?</>
are ordinary characters and there is no equivalent
for their functionality.
The delimiters for bounds are
<literal>\{</> and <literal>\}</>,
with <literal>{</> and <literal>}</>
by themselves ordinary characters.
The parentheses for nested subexpressions are
<literal>\(</> and <literal>\)</>,
with <literal>(</> and <literal>)</> by themselves ordinary characters.
<literal>^</> is an ordinary character except at the beginning of the
RE or the beginning of a parenthesized subexpression,
<literal>$</> is an ordinary character except at the end of the
RE or the end of a parenthesized subexpression,
and <literal>*</> is an ordinary character if it appears at the beginning
of the RE or the beginning of a parenthesized subexpression
(after a possible leading <literal>^</>).
Finally, single-digit back references are available, and
<literal>\&lt;</> and <literal>\&gt;</>
are synonyms for
<literal>[[:&lt;:]]</> and <literal>[[:&gt;:]]</>
respectively; no other escapes are available.
</para>
</sect3>
<!-- end re_syntax.n man page -->
</sect2>
</sect1> </sect1>
......
doc/src/sgml/release.sgml
View file @ 7bcc6d98
<!-- <!--
$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.184 2003/02/02 23:46:38 tgl Exp $ $Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.185 2003/02/05 17:41:32 tgl Exp $
--> -->
<appendix id="release"> <appendix id="release">
...@@ -24,6 +24,7 @@ CDATA means the content is "SGML-free", so you can write without ...@@ -24,6 +24,7 @@ CDATA means the content is "SGML-free", so you can write without
worries about funny characters. worries about funny characters.
--> -->
<literallayout><![CDATA[ <literallayout><![CDATA[
New regular expression package, many more regexp features (most of Perl5)
Can now do EXPLAIN ... EXECUTE to see plan used for a prepared query Can now do EXPLAIN ... EXECUTE to see plan used for a prepared query
Explicit JOINs no longer constrain query plan, unless JOIN_COLLAPSE_LIMIT = 1 Explicit JOINs no longer constrain query plan, unless JOIN_COLLAPSE_LIMIT = 1
Performance of "foo IN (SELECT ...)" queries has been considerably improved Performance of "foo IN (SELECT ...)" queries has been considerably improved
......
src/backend/regex/COPYRIGHT
View file @ 7bcc6d98
Copyright 1992, 1993, 1994 Henry Spencer. All rights reserved. This regular expression package was originally developed by Henry Spencer.
This software is not subject to any license of the American Telephone It bears the following copyright notice:
and Telegraph Company or of the Regents of the University of California.
**********************************************************************
Permission is granted to anyone to use this software for any purpose on
any computer system, and to alter it and redistribute it, subject Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
to the following restrictions:
Development of this software was funded, in part, by Cray Research Inc.,
1. The author is not responsible for the consequences of use of this UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
software, no matter how awful, even if they arise from flaws in it. Corporation, none of whom are responsible for the results. The author
thanks all of them.
2. The origin of this software must not be misrepresented, either by
explicit claim or by omission. Since few users ever read sources, Redistribution and use in source and binary forms -- with or without
credits must appear in the documentation. modification -- are permitted for any purpose, provided that
redistributions in source form retain this entire copyright notice and
3. Altered versions must be plainly marked as such, and must not be indicate the origin and nature of any modifications.
misrepresented as being the original software. Since few users
ever read sources, credits must appear in the documentation. I'd appreciate being given credit for this package in the documentation
of software which uses it, but that is not a requirement.
4. This notice may not be removed or altered.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
/*- AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* Copyright (c) 1994 HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* The Regents of the University of California. All rights reserved. EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* Redistribution and use in source and binary forms, with or without OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* modification, are permitted provided that the following conditions WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* are met: OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* 1. Redistributions of source code must retain the above copyright ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright **********************************************************************
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution. PostgreSQL adopted the code out of Tcl 8.4.1. Portions of regc_locale.c
* 3. All advertising materials mentioning features or use of this software and re_syntax.n were developed by Tcl developers other than Henry; these
* must display the following acknowledgement: files bear the Tcl copyright and license notice:
* This product includes software developed by the University of
* California, Berkeley and its contributors. **********************************************************************
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software This software is copyrighted by the Regents of the University of
* without specific prior written permission. California, Sun Microsystems, Inc., Scriptics Corporation, ActiveState
* Corporation and other parties. The following terms apply to all files
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND associated with the software unless explicitly disclaimed in
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE individual files.
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE The authors hereby grant permission to use, copy, modify, distribute,
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL and license this software and its documentation for any purpose, provided
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS that existing copyright notices are retained in all copies and that this
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) notice is included verbatim in any distributions. No written agreement,
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT license, or royalty fee is required for any of the authorized uses.
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY Modifications to this software may be copyrighted by their authors
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF and need not follow the licensing terms described here, provided that
* SUCH DAMAGE. the new terms are clearly indicated on the first page of each file where
* they apply.
* @(#)COPYRIGHT 8.1 (Berkeley) 3/16/94
*/ IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. THIS SOFTWARE
IS PROVIDED ON AN "AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE
NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR
MODIFICATIONS.
GOVERNMENT USE: If you are acquiring this software on behalf of the
U.S. government, the Government shall have only "Restricted Rights"
in the software and related documentation as defined in the Federal
Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you
are acquiring the software on behalf of the Department of Defense, the
software shall be classified as "Commercial Computer Software" and the
Government shall have only "Restricted Rights" as defined in Clause
252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
authors grant the U.S. Government and others acting in its behalf
permission to use and distribute the software in accordance with the
terms specified in this license.
**********************************************************************
Subsequent modifications to the code by the PostgreSQL project follow
the same license terms as the rest of PostgreSQL.
src/backend/regex/Makefile
View file @ 7bcc6d98
#------------------------------------------------------------------------- #-------------------------------------------------------------------------
# #
# Makefile-- # Makefile--
# Makefile for regex # Makefile for backend/regex
# #
# IDENTIFICATION # IDENTIFICATION
# $Header: /cvsroot/pgsql/src/backend/regex/Makefile,v 1.19 2002/09/16 16:02:43 momjian Exp $ # $Header: /cvsroot/pgsql/src/backend/regex/Makefile,v 1.20 2003/02/05 17:41:32 tgl Exp $
# #
#------------------------------------------------------------------------- #-------------------------------------------------------------------------
...@@ -12,23 +12,17 @@ subdir = src/backend/regex ...@@ -12,23 +12,17 @@ subdir = src/backend/regex
top_builddir = ../../.. top_builddir = ../../..
include $(top_builddir)/src/Makefile.global include $(top_builddir)/src/Makefile.global
override CPPFLAGS += -DPOSIX_MISTAKE
OBJS = regcomp.o regerror.o regexec.o regfree.o OBJS = regcomp.o regerror.o regexec.o regfree.o
DEBUGOBJ += ../utils/mb/SUBSYS.o
all: SUBSYS.o all: SUBSYS.o
SUBSYS.o: $(OBJS) SUBSYS.o: $(OBJS)
$(LD) $(LDREL) $(LDOUT) SUBSYS.o $(OBJS) $(LD) $(LDREL) $(LDOUT) SUBSYS.o $(OBJS)
regexec.o: regexec.c engine.c # mark inclusion dependencies between .c files explicitly
regcomp.o: regcomp.c regc_lex.c regc_color.c regc_nfa.c regc_cvec.c regc_locale.c
# retest will not compile because multibyte is now enabled by default regexec.o: regexec.c rege_dfa.c
# and the multibyte calls require /mmgr, /adt, and other calls that
# are complex for linkage, bjm 2002-09-16
#retest: retest.o SUBSYS.o $(DEBUGOBJ)
# $(CC) $(CFLAGS) $(LDFLAGS) $^ $(LIBS) -o $@
clean: clean:
rm -f SUBSYS.o $(OBJS) retest retest.o rm -f SUBSYS.o $(OBJS)
src/backend/regex/WHATSNEW deleted 100644 → 0
View file @ 32c3db0f
# @(#)WHATSNEW 8.3 (Berkeley) 3/18/94
New in alpha3.4: The complex bug alluded to below has been fixed (in a
slightly kludgey temporary way that may hurt efficiency a bit; this is
another "get it out the door for 4.4" release). The tests at the end of
the tests file have accordingly been uncommented. The primary sign of
the bug was that something like a?b matching ab matched b rather than ab.
(The bug was essentially specific to this exact situation, else it would
have shown up earlier.)
New in alpha3.3: The definition of word boundaries has been altered
slightly, to more closely match the usual programming notion that "_"
is an alphabetic. Stuff used for pre-ANSI systems is now in a subdir,
and the makefile no longer alludes to it in mysterious ways. The
makefile has generally been cleaned up some. Fixes have been made
(again!) so that the regression test will run without -DREDEBUG, at
the cost of weaker checking. A workaround for a bug in some folks'
<assert.h> has been added. And some more things have been added to
tests, including a couple right at the end which are commented out
because the code currently flunks them (complex bug; fix coming).
Plus the usual minor cleanup.
New in alpha3.2: Assorted bits of cleanup and portability improvement
(the development base is now a BSDI system using GCC instead of an ancient
Sun system, and the newer compiler exposed some glitches). Fix for a
serious bug that affected REs using many [] (including REG_ICASE REs
because of the way they are implemented), *sometimes*, depending on
memory-allocation patterns. The header-file prototypes no longer name
the parameters, avoiding possible name conflicts. The possibility that
some clot has defined CHAR_MIN as (say) `-128' instead of `(-128)' is
now handled gracefully. "uchar" is no longer used as an internal type
name (too many people have the same idea). Still the same old lousy
performance, alas.
New in alpha3.1: Basically nothing, this release is just a bookkeeping
convenience. Stay tuned.
New in alpha3.0: Performance is no better, alas, but some fixes have been
made and some functionality has been added. (This is basically the "get
it out the door in time for 4.4" release.) One bug fix: regfree() didn't
free the main internal structure (how embarrassing). It is now possible
to put NULs in either the RE or the target string, using (resp.) a new
REG_PEND flag and the old REG_STARTEND flag. The REG_NOSPEC flag to
regcomp() makes all characters ordinary, so you can match a literal
string easily (this will become more useful when performance improves!).
There are now primitives to match beginnings and ends of words, although
the syntax is disgusting and so is the implementation. The REG_ATOI
debugging interface has changed a bit. And there has been considerable
internal cleanup of various kinds.
New in alpha2.3: Split change list out of README, and moved flags notes
into Makefile. Macro-ized the name of regex(7) in regex(3), since it has
to change for 4.4BSD. Cleanup work in engine.c, and some new regression
tests to catch tricky cases thereof.
New in alpha2.2: Out-of-date manpages updated. Regerror() acquires two
small extensions -- REG_ITOA and REG_ATOI -- which avoid debugging kludges
in my own test program and might be useful to others for similar purposes.
The regression test will now compile (and run) without REDEBUG. The
BRE \$ bug is fixed. Most uses of "uchar" are gone; it's all chars now.
Char/uchar parameters are now written int/unsigned, to avoid possible
portability problems with unpromoted parameters. Some unsigned casts have
been introduced to minimize portability problems with shifting into sign
bits.
New in alpha2.1: Lots of little stuff, cleanup and fixes. The one big
thing is that regex.h is now generated, using mkh, rather than being
supplied in the distribution; due to circularities in dependencies,
you have to build regex.h explicitly by "make h". The two known bugs
have been fixed (and the regression test now checks for them), as has a
problem with assertions not being suppressed in the absence of REDEBUG.
No performance work yet.
New in alpha2: Backslash-anything is an ordinary character, not an
error (except, of course, for the handful of backslashed metacharacters
in BREs), which should reduce script breakage. The regression test
checks *where* null strings are supposed to match, and has generally
been tightened up somewhat. Small bug fixes in parameter passing (not
harmful, but technically errors) and some other areas. Debugging
invoked by defining REDEBUG rather than not defining NDEBUG.
New in alpha+3: full prototyping for internal routines, using a little
helper program, mkh, which extracts prototypes given in stylized comments.
More minor cleanup. Buglet fix: it's CHAR_BIT, not CHAR_BITS. Simple
pre-screening of input when a literal string is known to be part of the
RE; this does wonders for performance.
New in alpha+2: minor bits of cleanup. Notably, the number "32" for the
word width isn't hardwired into regexec.c any more, the public header
file prototypes the functions if __STDC__ is defined, and some small typos
in the manpages have been fixed.
New in alpha+1: improvements to the manual pages, and an important
extension, the REG_STARTEND option to regexec().
src/backend/regex/engine.c deleted 100644 → 0
View file @ 32c3db0f
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)engine.c 8.5 (Berkeley) 3/20/94
*/
#include "postgres.h"
/*
* The matching engine and friends. This file is #included by regexec.c
* after suitable #defines of a variety of macros used herein, so that
* different state representations can be used without duplicating masses
* of code.
*/
#ifdef SNAMES
#define matcher smatcher
#define fast sfast
#define slow sslow
#define dissect sdissect
#define backref sbackref
#define step sstep
#define print sprint
#define at sat
#define match smat
#endif
#ifdef LNAMES
#define matcher lmatcher
#define fast lfast
#define slow lslow
#define dissect ldissect
#define backref lbackref
#define step lstep
#define print lprint
#define at lat
#define match lmat
#endif
/* another structure passed up and down to avoid zillions of parameters */
struct match
{
struct re_guts *g;
int eflags;
regmatch_t *pmatch; /* [nsub+1] (0 element unused) */
pg_wchar *offp; /* offsets work from here */
pg_wchar *beginp; /* start of string -- virtual NUL precedes */
pg_wchar *endp; /* end of string -- virtual NUL here */
pg_wchar *coldp; /* can be no match starting before here */
pg_wchar **lastpos; /* [nplus+1] */
STATEVARS;
states st; /* current states */
states fresh; /* states for a fresh start */
states tmp; /* temporary */
states empty; /* empty set of states */
};
static int matcher(struct re_guts * g, pg_wchar *string, size_t nmatch,
regmatch_t *pmatch, int eflags);
static pg_wchar *dissect(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst);
static pg_wchar *backref(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst, sopno lev);
static pg_wchar *fast(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst);
static pg_wchar *slow(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst);
static states step(struct re_guts * g, sopno start,
sopno stop, states bef, int ch, states aft);
#define BOL (OUT+1)
#define EOL (BOL+1)
#define BOLEOL (BOL+2)
#define NOTHING (BOL+3)
#define BOW (BOL+4)
#define EOW (BOL+5)
#define CODEMAX (BOL+5) /* highest code used */
#define NONCHAR(c) ((c) > 16777216) /* 16777216 == 2^24 == 3 bytes */
#define NNONCHAR (CODEMAX-16777216)
#ifdef REDEBUG
static void print(struct match * m, pg_wchar *caption, states st, int ch,
FILE *d);
static void at(struct match * m, pg_wchar *title, pg_wchar *start,
pg_wchar *stop, sopno startst, sopno stopst);
static pg_wchar *pchar(int ch);
static int pg_isprint(int c);
#endif
#ifdef REDEBUG
#define SP(t, s, c) print(m, t, s, c, stdout)
#define AT(t, p1, p2, s1, s2) at(m, t, p1, p2, s1, s2)
#define NOTE(str) \
do { \
if (m->eflags&REG_TRACE) \
printf("=%s\n", (str)); \
} while (0)
#else
#define SP(t, s, c) /* nothing */
#define AT(t, p1, p2, s1, s2) /* nothing */
#define NOTE(s) /* nothing */
#endif
/*
* matcher - the actual matching engine
*/
static int /* 0 success, REG_NOMATCH failure */
matcher(struct re_guts * g, pg_wchar *string, size_t nmatch,
regmatch_t *pmatch, int eflags)
{
pg_wchar *endp;
int i;
struct match mv;
struct match *m = &mv;
pg_wchar *dp;
const sopno gf = g->firststate + 1; /* +1 for OEND */
const sopno gl = g->laststate;
pg_wchar *start;
pg_wchar *stop;
/* simplify the situation where possible */
if (g->cflags & REG_NOSUB)
nmatch = 0;
if (eflags & REG_STARTEND)
{
start = string + pmatch[0].rm_so;
stop = string + pmatch[0].rm_eo;
}
else
{
start = string;
stop = start + pg_wchar_strlen(start);
}
if (stop < start)
return REG_INVARG;
/* prescreening; this does wonders for this rather slow code */
if (g->must != NULL)
{
for (dp = start; dp < stop; dp++)
if (*dp == g->must[0] && stop - dp >= g->mlen &&
memcmp(dp, g->must, (size_t) (g->mlen * sizeof(pg_wchar))) == 0
)
break;
if (dp == stop) /* we didn't find g->must */
return REG_NOMATCH;
}
/* match struct setup */
m->g = g;
m->eflags = eflags;
m->pmatch = NULL;
m->lastpos = NULL;
m->offp = string;
m->beginp = start;
m->endp = stop;
STATESETUP(m, 4);
SETUP(m->st);
SETUP(m->fresh);
SETUP(m->tmp);
SETUP(m->empty);
CLEAR(m->empty);
/* this loop does only one repetition except for backrefs */
for (;;)
{
endp = fast(m, start, stop, gf, gl);
if (endp == NULL)
{ /* a miss */
STATETEARDOWN(m);
return REG_NOMATCH;
}
if (nmatch == 0 && !g->backrefs)
break; /* no further info needed */
/* where? */
assert(m->coldp != NULL);
for (;;)
{
NOTE("finding start");
endp = slow(m, m->coldp, stop, gf, gl);
if (endp != NULL)
break;
assert(m->coldp < m->endp);
m->coldp++;
}
if (nmatch == 1 && !g->backrefs)
break; /* no further info needed */
/* oh my, he wants the subexpressions... */
if (m->pmatch == NULL)
m->pmatch = (regmatch_t *) malloc((m->g->nsub + 1) *
sizeof(regmatch_t));
if (m->pmatch == NULL)
{
STATETEARDOWN(m);
return REG_ESPACE;
}
for (i = 1; i <= m->g->nsub; i++)
m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1;
if (!g->backrefs && !(m->eflags & REG_BACKR))
{
NOTE("dissecting");
dp = dissect(m, m->coldp, endp, gf, gl);
}
else
{
if (g->nplus > 0 && m->lastpos == NULL)
m->lastpos = (pg_wchar **) malloc((g->nplus + 1) *
sizeof(pg_wchar *));
if (g->nplus > 0 && m->lastpos == NULL)
{
free(m->pmatch);
STATETEARDOWN(m);
return REG_ESPACE;
}
NOTE("backref dissect");
dp = backref(m, m->coldp, endp, gf, gl, (sopno) 0);
}
if (dp != NULL)
break;
/* uh-oh... we couldn't find a subexpression-level match */
assert(g->backrefs); /* must be back references doing it */
assert(g->nplus == 0 || m->lastpos != NULL);
for (;;)
{
if (dp != NULL || endp <= m->coldp)
break; /* defeat */
NOTE("backoff");
endp = slow(m, m->coldp, endp - 1, gf, gl);
if (endp == NULL)
break; /* defeat */
/* try it on a shorter possibility */
#ifndef NDEBUG
for (i = 1; i <= m->g->nsub; i++)
{
assert(m->pmatch[i].rm_so == -1);
assert(m->pmatch[i].rm_eo == -1);
}
#endif
NOTE("backoff dissect");
dp = backref(m, m->coldp, endp, gf, gl, (sopno) 0);
}
assert(dp == NULL || dp == endp);
if (dp != NULL) /* found a shorter one */
break;
/* despite initial appearances, there is no match here */
NOTE("false alarm");
start = m->coldp + 1; /* recycle starting later */
assert(start <= stop);
}
/* fill in the details if requested */
if (nmatch > 0)
{
pmatch[0].rm_so = m->coldp - m->offp;
pmatch[0].rm_eo = endp - m->offp;
}
if (nmatch > 1)
{
assert(m->pmatch != NULL);
for (i = 1; i < nmatch; i++)
if (i <= m->g->nsub)
pmatch[i] = m->pmatch[i];
else
{
pmatch[i].rm_so = -1;
pmatch[i].rm_eo = -1;
}
}
if (m->pmatch != NULL)
free((pg_wchar *) m->pmatch);
if (m->lastpos != NULL)
free((pg_wchar *) m->lastpos);
STATETEARDOWN(m);
return 0;
}
/*
* dissect - figure out what matched what, no back references
*/
static pg_wchar * /* == stop (success) always */
dissect(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst)
{
int i;
sopno ss; /* start sop of current subRE */
sopno es; /* end sop of current subRE */
pg_wchar *sp; /* start of string matched by it */
pg_wchar *stp; /* string matched by it cannot pass here */
pg_wchar *rest; /* start of rest of string */
pg_wchar *tail; /* string unmatched by rest of RE */
sopno ssub; /* start sop of subsubRE */
sopno esub; /* end sop of subsubRE */
pg_wchar *ssp; /* start of string matched by subsubRE */
pg_wchar *sep; /* end of string matched by subsubRE */
pg_wchar *oldssp; /* previous ssp */
pg_wchar *dp;
AT("diss", start, stop, startst, stopst);
sp = start;
for (ss = startst; ss < stopst; ss = es)
{
/* identify end of subRE */
es = ss;
switch (OP(m->g->strip[es]))
{
case OPLUS_:
case OQUEST_:
es += OPND(m->g->strip[es]);
break;
case OCH_:
while (OP(m->g->strip[es]) != O_CH)
es += OPND(m->g->strip[es]);
break;
}
es++;
/* figure out what it matched */
switch (OP(m->g->strip[ss]))
{
case OEND:
assert(nope);
break;
case OCHAR:
sp++;
break;
case OBOL:
case OEOL:
case OBOW:
case OEOW:
break;
case OANY:
case OANYOF:
sp++;
break;
case OBACK_:
case O_BACK:
assert(nope);
break;
/* cases where length of match is hard to find */
case OQUEST_:
stp = stop;
for (;;)
{
/* how long could this one be? */
rest = slow(m, sp, stp, ss, es);
assert(rest != NULL); /* it did match */
/* could the rest match the rest? */
tail = slow(m, rest, stop, es, stopst);
if (tail == stop)
break; /* yes! */
/* no -- try a shorter match for this one */
stp = rest - 1;
assert(stp >= sp); /* it did work */
}
ssub = ss + 1;
esub = es - 1;
/* did innards match? */
if (slow(m, sp, rest, ssub, esub) != NULL)
{
dp = dissect(m, sp, rest, ssub, esub);
assert(dp == rest);
}
else
/* no */
assert(sp == rest);
sp = rest;
break;
case OPLUS_:
stp = stop;
for (;;)
{
/* how long could this one be? */
rest = slow(m, sp, stp, ss, es);
assert(rest != NULL); /* it did match */
/* could the rest match the rest? */
tail = slow(m, rest, stop, es, stopst);
if (tail == stop)
break; /* yes! */
/* no -- try a shorter match for this one */
stp = rest - 1;
assert(stp >= sp); /* it did work */
}
ssub = ss + 1;
esub = es - 1;
ssp = sp;
oldssp = ssp;
for (;;)
{ /* find last match of innards */
sep = slow(m, ssp, rest, ssub, esub);
if (sep == NULL || sep == ssp)
break; /* failed or matched null */
oldssp = ssp; /* on to next try */
ssp = sep;
}
if (sep == NULL)
{
/* last successful match */
sep = ssp;
ssp = oldssp;
}
assert(sep == rest); /* must exhaust substring */
assert(slow(m, ssp, sep, ssub, esub) == rest);
dp = dissect(m, ssp, sep, ssub, esub);
assert(dp == sep);
sp = rest;
break;
case OCH_:
stp = stop;
for (;;)
{
/* how long could this one be? */
rest = slow(m, sp, stp, ss, es);
assert(rest != NULL); /* it did match */
/* could the rest match the rest? */
tail = slow(m, rest, stop, es, stopst);
if (tail == stop)
break; /* yes! */
/* no -- try a shorter match for this one */
stp = rest - 1;
assert(stp >= sp); /* it did work */
}
ssub = ss + 1;
esub = ss + OPND(m->g->strip[ss]) - 1;
assert(OP(m->g->strip[esub]) == OOR1);
for (;;)
{ /* find first matching branch */
if (slow(m, sp, rest, ssub, esub) == rest)
break; /* it matched all of it */
/* that one missed, try next one */
assert(OP(m->g->strip[esub]) == OOR1);
esub++;
assert(OP(m->g->strip[esub]) == OOR2);
ssub = esub + 1;
esub += OPND(m->g->strip[esub]);
if (OP(m->g->strip[esub]) == OOR2)
esub--;
else
assert(OP(m->g->strip[esub]) == O_CH);
}
dp = dissect(m, sp, rest, ssub, esub);
assert(dp == rest);
sp = rest;
break;
case O_PLUS:
case O_QUEST:
case OOR1:
case OOR2:
case O_CH:
assert(nope);
break;
case OLPAREN:
i = OPND(m->g->strip[ss]);
assert(0 < i && i <= m->g->nsub);
m->pmatch[i].rm_so = sp - m->offp;
break;
case ORPAREN:
i = OPND(m->g->strip[ss]);
assert(0 < i && i <= m->g->nsub);
m->pmatch[i].rm_eo = sp - m->offp;
break;
default: /* uh oh */
assert(nope);
break;
}
}
assert(sp == stop);
return sp;
}
/*
* backref - figure out what matched what, figuring in back references
*
* lev is PLUS nesting level
*/
static pg_wchar * /* == stop (success) or NULL (failure) */
backref(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst, sopno lev)
{
int i;
sopno ss; /* start sop of current subRE */
pg_wchar *sp; /* start of string matched by it */
sopno ssub; /* start sop of subsubRE */
sopno esub; /* end sop of subsubRE */
pg_wchar *ssp; /* start of string matched by subsubRE */
pg_wchar *dp;
size_t len;
int hard;
sop s;
regoff_t offsave;
cset *cs;
AT("back", start, stop, startst, stopst);
sp = start;
/* get as far as we can with easy stuff */
hard = 0;
for (ss = startst; !hard && ss < stopst; ss++)
switch (OP(s = m->g->strip[ss]))
{
case OCHAR:
if (sp == stop || *sp++ != (pg_wchar) OPND(s))
return NULL;
break;
case OANY:
if (sp == stop)
return NULL;
sp++;
break;
case OANYOF:
cs = &m->g->sets[OPND(s)];
if (sp == stop || !CHIN(cs, *sp++))
return NULL;
break;
case OBOL:
if ((sp == m->beginp && !(m->eflags & REG_NOTBOL)) ||
(sp < m->endp && *(sp - 1) == '\n' &&
(m->g->cflags & REG_NEWLINE)))
{ /* yes */
}
else
return NULL;
break;
case OEOL:
if ((sp == m->endp && !(m->eflags & REG_NOTEOL)) ||
(sp < m->endp && *sp == '\n' &&
(m->g->cflags & REG_NEWLINE)))
{ /* yes */
}
else
return NULL;
break;
case OBOW:
if (((sp == m->beginp && !(m->eflags & REG_NOTBOL)) ||
(sp < m->endp && *(sp - 1) == '\n' &&
(m->g->cflags & REG_NEWLINE)) ||
(sp > m->beginp &&
!ISWORD(*(sp - 1)))) &&
(sp < m->endp && ISWORD(*sp)))
{ /* yes */
}
else
return NULL;
break;
case OEOW:
if (((sp == m->endp && !(m->eflags & REG_NOTEOL)) ||
(sp < m->endp && *sp == '\n' &&
(m->g->cflags & REG_NEWLINE)) ||
(sp < m->endp && !ISWORD(*sp))) &&
(sp > m->beginp && ISWORD(*(sp - 1))))
{ /* yes */
}
else
return NULL;
break;
case O_QUEST:
break;
case OOR1: /* matches null but needs to skip */
ss++;
s = m->g->strip[ss];
do
{
assert(OP(s) == OOR2);
ss += OPND(s);
} while (OP(s = m->g->strip[ss]) != O_CH);
/* note that the ss++ gets us past the O_CH */
break;
default: /* have to make a choice */
hard = 1;
break;
}
if (!hard)
{ /* that was it! */
if (sp != stop)
return NULL;
return sp;
}
ss--; /* adjust for the for's final increment */
/* the hard stuff */
AT("hard", sp, stop, ss, stopst);
s = m->g->strip[ss];
switch (OP(s))
{
case OBACK_: /* the vilest depths */
i = OPND(s);
assert(0 < i && i <= m->g->nsub);
if (m->pmatch[i].rm_eo == -1)
return NULL;
assert(m->pmatch[i].rm_so != -1);
len = m->pmatch[i].rm_eo - m->pmatch[i].rm_so;
assert(stop - m->beginp >= len);
if (sp > stop - len)
return NULL; /* not enough left to match */
ssp = m->offp + m->pmatch[i].rm_so;
if (memcmp(sp, ssp, len) != 0)
return NULL;
while (m->g->strip[ss] != SOP(O_BACK, i))
ss++;
return backref(m, sp + len, stop, ss + 1, stopst, lev);
break;
case OQUEST_: /* to null or not */
dp = backref(m, sp, stop, ss + 1, stopst, lev);
if (dp != NULL)
return dp; /* not */
return backref(m, sp, stop, ss + OPND(s) + 1, stopst, lev);
break;
case OPLUS_:
assert(m->lastpos != NULL);
assert(lev + 1 <= m->g->nplus);
m->lastpos[lev + 1] = sp;
return backref(m, sp, stop, ss + 1, stopst, lev + 1);
break;
case O_PLUS:
if (sp == m->lastpos[lev]) /* last pass matched null */
return backref(m, sp, stop, ss + 1, stopst, lev - 1);
/* try another pass */
m->lastpos[lev] = sp;
dp = backref(m, sp, stop, ss - OPND(s) + 1, stopst, lev);
if (dp == NULL)
return backref(m, sp, stop, ss + 1, stopst, lev - 1);
else
return dp;
break;
case OCH_: /* find the right one, if any */
ssub = ss + 1;
esub = ss + OPND(s) - 1;
assert(OP(m->g->strip[esub]) == OOR1);
for (;;)
{ /* find first matching branch */
dp = backref(m, sp, stop, ssub, esub, lev);
if (dp != NULL)
return dp;
/* that one missed, try next one */
if (OP(m->g->strip[esub]) == O_CH)
return NULL; /* there is none */
esub++;
assert(OP(m->g->strip[esub]) == OOR2);
ssub = esub + 1;
esub += OPND(m->g->strip[esub]);
if (OP(m->g->strip[esub]) == OOR2)
esub--;
else
assert(OP(m->g->strip[esub]) == O_CH);
}
break;
case OLPAREN: /* must undo assignment if rest fails */
i = OPND(s);
assert(0 < i && i <= m->g->nsub);
offsave = m->pmatch[i].rm_so;
m->pmatch[i].rm_so = sp - m->offp;
dp = backref(m, sp, stop, ss + 1, stopst, lev);
if (dp != NULL)
return dp;
m->pmatch[i].rm_so = offsave;
return NULL;
break;
case ORPAREN: /* must undo assignment if rest fails */
i = OPND(s);
assert(0 < i && i <= m->g->nsub);
offsave = m->pmatch[i].rm_eo;
m->pmatch[i].rm_eo = sp - m->offp;
dp = backref(m, sp, stop, ss + 1, stopst, lev);
if (dp != NULL)
return dp;
m->pmatch[i].rm_eo = offsave;
return NULL;
break;
default: /* uh oh */
assert(nope);
break;
}
/* "can't happen" */
assert(nope);
/* NOTREACHED */
return 0;
}
/*
* fast - step through the string at top speed
*/
static pg_wchar * /* where tentative match ended, or NULL */
fast(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst)
{
states st = m->st;
states fresh = m->fresh;
states tmp = m->tmp;
pg_wchar *p = start;
int c = (start == m->beginp) ? OUT : *(start - 1);
int lastc; /* previous c */
int flagch;
int i;
pg_wchar *coldp; /* last p after which no match was
* underway */
CLEAR(st);
SET1(st, startst);
st = step(m->g, startst, stopst, st, NOTHING, st);
ASSIGN(fresh, st);
SP("start", st, *p);
coldp = NULL;
for (;;)
{
/* next character */
lastc = c;
c = (p == m->endp) ? OUT : *p;
if (EQ(st, fresh))
coldp = p;
/* is there an EOL and/or BOL between lastc and c? */
flagch = '\0';
i = 0;
if ((lastc == '\n' && m->g->cflags & REG_NEWLINE) ||
(lastc == OUT && !(m->eflags & REG_NOTBOL)))
{
flagch = BOL;
i = m->g->nbol;
}
if ((c == '\n' && m->g->cflags & REG_NEWLINE) ||
(c == OUT && !(m->eflags & REG_NOTEOL)))
{
flagch = (flagch == BOL) ? BOLEOL : EOL;
i += m->g->neol;
}
if (i != 0)
{
for (; i > 0; i--)
st = step(m->g, startst, stopst, st, flagch, st);
SP("boleol", st, c);
}
/* how about a word boundary? */
if ((flagch == BOL || (lastc != OUT && !ISWORD(lastc))) &&
(c != OUT && ISWORD(c)))
flagch = BOW;
if ((lastc != OUT && ISWORD(lastc)) &&
(flagch == EOL || (c != OUT && !ISWORD(c))))
flagch = EOW;
if (flagch == BOW || flagch == EOW)
{
st = step(m->g, startst, stopst, st, flagch, st);
SP("boweow", st, c);
}
/* are we done? */
if (ISSET(st, stopst) || p == stop)
break; /* NOTE BREAK OUT */
/* no, we must deal with this character */
ASSIGN(tmp, st);
ASSIGN(st, fresh);
assert(c != OUT);
st = step(m->g, startst, stopst, tmp, c, st);
SP("aft", st, c);
assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
p++;
}
assert(coldp != NULL);
m->coldp = coldp;
if (ISSET(st, stopst))
return p + 1;
else
return NULL;
}
/*
* slow - step through the string more deliberately
*/
static pg_wchar * /* where it ended */
slow(struct match * m, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst)
{
states st = m->st;
states empty = m->empty;
states tmp = m->tmp;
pg_wchar *p = start;
int c = (start == m->beginp) ? OUT : *(start - 1);
int lastc; /* previous c */
int flagch;
int i;
pg_wchar *matchp; /* last p at which a match ended */
AT("slow", start, stop, startst, stopst);
CLEAR(st);
SET1(st, startst);
SP("sstart", st, *p);
st = step(m->g, startst, stopst, st, NOTHING, st);
matchp = NULL;
for (;;)
{
/* next character */
lastc = c;
c = (p == m->endp) ? OUT : *p;
/* is there an EOL and/or BOL between lastc and c? */
flagch = '\0';
i = 0;
if ((lastc == '\n' && m->g->cflags & REG_NEWLINE) ||
(lastc == OUT && !(m->eflags & REG_NOTBOL)))
{
flagch = BOL;
i = m->g->nbol;
}
if ((c == '\n' && m->g->cflags & REG_NEWLINE) ||
(c == OUT && !(m->eflags & REG_NOTEOL)))
{
flagch = (flagch == BOL) ? BOLEOL : EOL;
i += m->g->neol;
}
if (i != 0)
{
for (; i > 0; i--)
st = step(m->g, startst, stopst, st, flagch, st);
SP("sboleol", st, c);
}
/* how about a word boundary? */
if ((flagch == BOL || (lastc != OUT && !ISWORD(lastc))) &&
(c != OUT && ISWORD(c)))
flagch = BOW;
if ((lastc != OUT && ISWORD(lastc)) &&
(flagch == EOL || (c != OUT && !ISWORD(c))))
flagch = EOW;
if (flagch == BOW || flagch == EOW)
{
st = step(m->g, startst, stopst, st, flagch, st);
SP("sboweow", st, c);
}
/* are we done? */
if (ISSET(st, stopst))
matchp = p;
if (EQ(st, empty) || p == stop)
break; /* NOTE BREAK OUT */
/* no, we must deal with this character */
ASSIGN(tmp, st);
ASSIGN(st, empty);
assert(c != OUT);
st = step(m->g, startst, stopst, tmp, c, st);
SP("saft", st, c);
assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
p++;
}
return matchp;
}
/*
* step - map set of states reachable before char to set reachable after
*/
static states
step(struct re_guts * g,
sopno start, /* start state within strip */
sopno stop, /* state after stop state within strip */
states bef, /* states reachable before */
int ch, /* character or NONCHAR code */
states aft) /* states already known reachable after */
{
cset *cs;
sop s;
sopno pc;
onestate here; /* note, macros know this name */
sopno look;
int i;
for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here))
{
s = g->strip[pc];
switch (OP(s))
{
case OEND:
assert(pc == stop - 1);
break;
case OCHAR:
/* only characters can match */
assert(!NONCHAR(ch) || ch != (pg_wchar) OPND(s));
if (ch == (pg_wchar) OPND(s))
FWD(aft, bef, 1);
break;
case OBOL:
if (ch == BOL || ch == BOLEOL)
FWD(aft, bef, 1);
break;
case OEOL:
if (ch == EOL || ch == BOLEOL)
FWD(aft, bef, 1);
break;
case OBOW:
if (ch == BOW)
FWD(aft, bef, 1);
break;
case OEOW:
if (ch == EOW)
FWD(aft, bef, 1);
break;
case OANY:
if (!NONCHAR(ch))
FWD(aft, bef, 1);
break;
case OANYOF:
cs = &g->sets[OPND(s)];
if (!NONCHAR(ch) && CHIN(cs, ch))
FWD(aft, bef, 1);
break;
case OBACK_: /* ignored here */
case O_BACK:
FWD(aft, aft, 1);
break;
case OPLUS_: /* forward, this is just an empty */
FWD(aft, aft, 1);
break;
case O_PLUS: /* both forward and back */
FWD(aft, aft, 1);
i = ISSETBACK(aft, OPND(s));
BACK(aft, aft, OPND(s));
if (!i && ISSETBACK(aft, OPND(s)))
{
/* oho, must reconsider loop body */
pc -= OPND(s) + 1;
INIT(here, pc);
}
break;
case OQUEST_: /* two branches, both forward */
FWD(aft, aft, 1);
FWD(aft, aft, OPND(s));
break;
case O_QUEST: /* just an empty */
FWD(aft, aft, 1);
break;
case OLPAREN: /* not significant here */
case ORPAREN:
FWD(aft, aft, 1);
break;
case OCH_: /* mark the first two branches */
FWD(aft, aft, 1);
assert(OP(g->strip[pc + OPND(s)]) == OOR2);
FWD(aft, aft, OPND(s));
break;
case OOR1: /* done a branch, find the O_CH */
if (ISSTATEIN(aft, here))
{
for (look = 1;
OP(s = g->strip[pc + look]) != O_CH;
look += OPND(s))
assert(OP(s) == OOR2);
FWD(aft, aft, look);
}
break;
case OOR2: /* propagate OCH_'s marking */
FWD(aft, aft, 1);
if (OP(g->strip[pc + OPND(s)]) != O_CH)
{
assert(OP(g->strip[pc + OPND(s)]) == OOR2);
FWD(aft, aft, OPND(s));
}
break;
case O_CH: /* just empty */
FWD(aft, aft, 1);
break;
default: /* ooooops... */
assert(nope);
break;
}
}
return aft;
}
#ifdef REDEBUG
/*
* print - print a set of states
*/
static void
print(struct match * m, pg_wchar *caption, states st,
int ch, FILE *d)
{
struct re_guts *g = m->g;
int i;
int first = 1;
if (!(m->eflags & REG_TRACE))
return;
fprintf(d, "%s", caption);
if (ch != '\0')
fprintf(d, " %s", pchar(ch));
for (i = 0; i < g->nstates; i++)
if (ISSET(st, i))
{
fprintf(d, "%s%d", (first) ? "\t" : ", ", i);
first = 0;
}
fprintf(d, "\n");
}
/*
* at - print current situation
*/
static void
at(struct match * m, pg_wchar *title, pg_wchar *start, pg_wchar *stop,
sopno startst, sopno stopst)
{
if (!(m->eflags & REG_TRACE))
return;
printf("%s %s-", title, pchar(*start));
printf("%s ", pchar(*stop));
printf("%ld-%ld\n", (long) startst, (long) stopst);
}
#ifndef PCHARDONE
#define PCHARDONE /* only do this once */
/*
* pchar - make a character printable
*
* Is this identical to regchar() over in debug.c? Well, yes. But a
* duplicate here avoids having a debugging-capable regexec.o tied to
* a matching debug.o, and this is convenient. It all disappears in
* the non-debug compilation anyway, so it doesn't matter much.
*/
static pg_wchar * /* -> representation */
pchar(int ch)
{
static pg_wchar pbuf[10];
if (pg_isprint(ch) || ch == ' ')
sprintf(pbuf, "%c", ch);
else
sprintf(pbuf, "\\%o", ch);
return pbuf;
}
static int
pg_isprint(int c)
{
return (c >= 0 && c <= UCHAR_MAX && isprint((unsigned char) c));
}
#endif
#endif
#undef matcher
#undef fast
#undef slow
#undef dissect
#undef backref
#undef step
#undef print
#undef at
#undef match
src/backend/regex/re_format.7 deleted 100644 → 0
View file @ 32c3db0f
.\" Copyright (c) 1992, 1993, 1994 Henry Spencer.
.\" Copyright (c) 1992, 1993, 1994
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" Henry Spencer.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" @(#)re_format.7 8.3 (Berkeley) 3/20/94
.\"
.TH RE_FORMAT 7 "March 20, 1994"
.SH NAME
re_format \- POSIX 1003.2 regular expressions
.SH DESCRIPTION
Regular expressions (``RE''s),
as defined in POSIX 1003.2, come in two forms:
modern REs (roughly those of
.IR egrep ;
1003.2 calls these ``extended'' REs)
and obsolete REs (roughly those of
.IR ed ;
1003.2 ``basic'' REs).
Obsolete REs mostly exist for backward compatibility in some old programs;
they will be discussed at the end.
1003.2 leaves some aspects of RE syntax and semantics open;
`\(dg' marks decisions on these aspects that
may not be fully portable to other 1003.2 implementations.
.PP
A (modern) RE is one\(dg or more non-empty\(dg \fIbranches\fR,
separated by `|'.
It matches anything that matches one of the branches.
.PP
A branch is one\(dg or more \fIpieces\fR, concatenated.
It matches a match for the first, followed by a match for the second, etc.
.PP
A piece is an \fIatom\fR possibly followed
by a single\(dg `*', `+', `?', or \fIbound\fR.
An atom followed by `*' matches a sequence of 0 or more matches of the atom.
An atom followed by `+' matches a sequence of 1 or more matches of the atom.
An atom followed by `?' matches a sequence of 0 or 1 matches of the atom.
.PP
A \fIbound\fR is `{' followed by an unsigned decimal integer,
possibly followed by `,'
possibly followed by another unsigned decimal integer,
always followed by `}'.
The integers must lie between 0 and RE_DUP_MAX (255\(dg) inclusive,
and if there are two of them, the first may not exceed the second.
An atom followed by a bound containing one integer \fIi\fR
and no comma matches
a sequence of exactly \fIi\fR matches of the atom.
An atom followed by a bound
containing one integer \fIi\fR and a comma matches
a sequence of \fIi\fR or more matches of the atom.
An atom followed by a bound
containing two integers \fIi\fR and \fIj\fR matches
a sequence of \fIi\fR through \fIj\fR (inclusive) matches of the atom.
.PP
An atom is a regular expression enclosed in `()' (matching a match for the
regular expression),
an empty set of `()' (matching the null string)\(dg,
a \fIbracket expression\fR (see below), `.'
(matching any single character), `^' (matching the null string at the
beginning of a line), `$' (matching the null string at the
end of a line), a `\e' followed by one of the characters
`^.[$()|*+?{\e'
(matching that character taken as an ordinary character),
a `\e' followed by any other character\(dg
(matching that character taken as an ordinary character,
as if the `\e' had not been present\(dg),
or a single character with no other significance (matching that character).
A `{' followed by a character other than a digit is an ordinary
character, not the beginning of a bound\(dg.
It is illegal to end an RE with `\e'.
.PP
A \fIbracket expression\fR is a list of characters enclosed in `[]'.
It normally matches any single character from the list (but see below).
If the list begins with `^',
it matches any single character
(but see below) \fInot\fR from the rest of the list.
If two characters in the list are separated by `\-', this is shorthand
for the full \fIrange\fR of characters between those two (inclusive) in the
collating sequence,
e.g. `[0-9]' in ASCII matches any decimal digit.
It is illegal\(dg for two ranges to share an
endpoint, e.g. `a-c-e'.
Ranges are very collating-sequence-dependent,
and portable programs should avoid relying on them.
.PP
To include a literal `]' in the list, make it the first character
(following a possible `^').
To include a literal `\-', make it the first or last character,
or the second endpoint of a range.
To use a literal `\-' as the first endpoint of a range,
enclose it in `[.' and `.]' to make it a collating element (see below).
With the exception of these and some combinations using `[' (see next
paragraphs), all other special characters, including `\e', lose their
special significance within a bracket expression.
.PP
Within a bracket expression, a collating element (a character,
a multi-character sequence that collates as if it were a single character,
or a collating-sequence name for either)
enclosed in `[.' and `.]' stands for the
sequence of characters of that collating element.
The sequence is a single element of the bracket expression's list.
A bracket expression containing a multi-character collating element
can thus match more than one character,
e.g. if the collating sequence includes a `ch' collating element,
then the RE `[[.ch.]]*c' matches the first five characters
of `chchcc'.
.PP
Within a bracket expression, a collating element enclosed in `[=' and
`=]' is an equivalence class, standing for the sequences of characters
of all collating elements equivalent to that one, including itself.
(If there are no other equivalent collating elements,
the treatment is as if the enclosing delimiters were `[.' and `.]'.)
For example, if o and \o'o^' are the members of an equivalence class,
then `[[=o=]]', `[[=\o'o^'=]]', and `[o\o'o^']' are all synonymous.
An equivalence class may not\(dg be an endpoint
of a range.
.PP
Within a bracket expression, the name of a \fIcharacter class\fR enclosed
in `[:' and `:]' stands for the list of all characters belonging to that
class.
Standard character class names are:
.PP
.RS
.nf
.ta 3c 6c 9c
alnum digit punct
alpha graph space
blank lower upper
cntrl print xdigit
.fi
.RE
.PP
These stand for the character classes defined in
.IR ctype (3).
A locale may provide others.
A character class may not be used as an endpoint of a range.
.PP
There are two special cases\(dg of bracket expressions:
the bracket expressions `[[:<:]]' and `[[:>:]]' match the null string at
the beginning and end of a word respectively.
A word is defined as a sequence of
word characters
which is neither preceded nor followed by
word characters.
A word character is an
.I alnum
character (as defined by
.IR ctype (3))
or an underscore.
This is an extension,
compatible with but not specified by POSIX 1003.2,
and should be used with
caution in software intended to be portable to other systems.
.PP
In the event that an RE could match more than one substring of a given
string,
the RE matches the one starting earliest in the string.
If the RE could match more than one substring starting at that point,
it matches the longest.
Subexpressions also match the longest possible substrings, subject to
the constraint that the whole match be as long as possible,
with subexpressions starting earlier in the RE taking priority over
ones starting later.
Note that higher-level subexpressions thus take priority over
their lower-level component subexpressions.
.PP
Match lengths are measured in characters, not collating elements.
A null string is considered longer than no match at all.
For example,
`bb*' matches the three middle characters of `abbbc',
`(wee|week)(knights|nights)' matches all ten characters of `weeknights',
when `(.*).*' is matched against `abc' the parenthesized subexpression
matches all three characters, and
when `(a*)*' is matched against `bc' both the whole RE and the parenthesized
subexpression match the null string.
.PP
If case-independent matching is specified,
the effect is much as if all case distinctions had vanished from the
alphabet.
When an alphabetic that exists in multiple cases appears as an
ordinary character outside a bracket expression, it is effectively
transformed into a bracket expression containing both cases,
e.g. `x' becomes `[xX]'.
When it appears inside a bracket expression, all case counterparts
of it are added to the bracket expression, so that (e.g.) `[x]'
becomes `[xX]' and `[^x]' becomes `[^xX]'.
.PP
No particular limit is imposed on the length of REs\(dg.
Programs intended to be portable should not employ REs longer
than 256 bytes,
as an implementation can refuse to accept such REs and remain
POSIX-compliant.
.PP
Obsolete (``basic'') regular expressions differ in several respects.
`|', `+', and `?' are ordinary characters and there is no equivalent
for their functionality.
The delimiters for bounds are `\e{' and `\e}',
with `{' and `}' by themselves ordinary characters.
The parentheses for nested subexpressions are `\e(' and `\e)',
with `(' and `)' by themselves ordinary characters.
`^' is an ordinary character except at the beginning of the
RE or\(dg the beginning of a parenthesized subexpression,
`$' is an ordinary character except at the end of the
RE or\(dg the end of a parenthesized subexpression,
and `*' is an ordinary character if it appears at the beginning of the
RE or the beginning of a parenthesized subexpression
(after a possible leading `^').
Finally, there is one new type of atom, a \fIback reference\fR:
`\e' followed by a non-zero decimal digit \fId\fR
matches the same sequence of characters
matched by the \fId\fRth parenthesized subexpression
(numbering subexpressions by the positions of their opening parentheses,
left to right),
so that (e.g.) `\e([bc]\e)\e1' matches `bb' or `cc' but not `bc'.
.SH SEE ALSO
regex(3)
.PP
POSIX 1003.2, section 2.8 (Regular Expression Notation).
.SH BUGS
Having two kinds of REs is a botch.
.PP
The current 1003.2 spec says that `)' is an ordinary character in
the absence of an unmatched `(';
this was an unintentional result of a wording error,
and change is likely.
Avoid relying on it.
.PP
Back references are a dreadful botch,
posing major problems for efficient implementations.
They are also somewhat vaguely defined
(does
`a\e(\e(b\e)*\e2\e)*d' match `abbbd'?).
Avoid using them.
.PP
1003.2's specification of case-independent matching is vague.
The ``one case implies all cases'' definition given above
is current consensus among implementors as to the right interpretation.
.PP
The syntax for word boundaries is incredibly ugly.
src/backend/regex/re_syntax.n 0 → 100644
View file @ 7bcc6d98
'\"
'\" Copyright (c) 1998 Sun Microsystems, Inc.
'\" Copyright (c) 1999 Scriptics Corporation
'\"
'\" This software is copyrighted by the Regents of the University of
'\" California, Sun Microsystems, Inc., Scriptics Corporation, ActiveState
'\" Corporation and other parties. The following terms apply to all files
'\" associated with the software unless explicitly disclaimed in
'\" individual files.
'\"
'\" The authors hereby grant permission to use, copy, modify, distribute,
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'\" RCS: @(#) Id: re_syntax.n,v 1.3 1999/07/14 19:09:36 jpeek Exp
'\"
.so man.macros
.TH re_syntax n "8.1" Tcl "Tcl Built-In Commands"
.BS
.SH NAME
re_syntax \- Syntax of Tcl regular expressions.
.BE
.SH DESCRIPTION
.PP
A \fIregular expression\fR describes strings of characters.
It's a pattern that matches certain strings and doesn't match others.
.SH "DIFFERENT FLAVORS OF REs"
Regular expressions (``RE''s), as defined by POSIX, come in two
flavors: \fIextended\fR REs (``EREs'') and \fIbasic\fR REs (``BREs'').
EREs are roughly those of the traditional \fIegrep\fR, while BREs are
roughly those of the traditional \fIed\fR. This implementation adds
a third flavor, \fIadvanced\fR REs (``AREs''), basically EREs with
some significant extensions.
.PP
This manual page primarily describes AREs. BREs mostly exist for
backward compatibility in some old programs; they will be discussed at
the end. POSIX EREs are almost an exact subset of AREs. Features of
AREs that are not present in EREs will be indicated.
.SH "REGULAR EXPRESSION SYNTAX"
.PP
Tcl regular expressions are implemented using the package written by
Henry Spencer, based on the 1003.2 spec and some (not quite all) of
the Perl5 extensions (thanks, Henry!). Much of the description of
regular expressions below is copied verbatim from his manual entry.
.PP
An ARE is one or more \fIbranches\fR,
separated by `\fB|\fR',
matching anything that matches any of the branches.
.PP
A branch is zero or more \fIconstraints\fR or \fIquantified atoms\fR,
concatenated.
It matches a match for the first, followed by a match for the second, etc;
an empty branch matches the empty string.
.PP
A quantified atom is an \fIatom\fR possibly followed
by a single \fIquantifier\fR.
Without a quantifier, it matches a match for the atom.
The quantifiers,
and what a so-quantified atom matches, are:
.RS 2
.TP 6
\fB*\fR
a sequence of 0 or more matches of the atom
.TP
\fB+\fR
a sequence of 1 or more matches of the atom
.TP
\fB?\fR
a sequence of 0 or 1 matches of the atom
.TP
\fB{\fIm\fB}\fR
a sequence of exactly \fIm\fR matches of the atom
.TP
\fB{\fIm\fB,}\fR
a sequence of \fIm\fR or more matches of the atom
.TP
\fB{\fIm\fB,\fIn\fB}\fR
a sequence of \fIm\fR through \fIn\fR (inclusive) matches of the atom;
\fIm\fR may not exceed \fIn\fR
.TP
\fB*? +? ?? {\fIm\fB}? {\fIm\fB,}? {\fIm\fB,\fIn\fB}?\fR
\fInon-greedy\fR quantifiers,
which match the same possibilities,
but prefer the smallest number rather than the largest number
of matches (see MATCHING)
.RE
.PP
The forms using
\fB{\fR and \fB}\fR
are known as \fIbound\fRs.
The numbers
\fIm\fR and \fIn\fR are unsigned decimal integers
with permissible values from 0 to 255 inclusive.
.PP
An atom is one of:
.RS 2
.TP 6
\fB(\fIre\fB)\fR
(where \fIre\fR is any regular expression)
matches a match for
\fIre\fR, with the match noted for possible reporting
.TP
\fB(?:\fIre\fB)\fR
as previous,
but does no reporting
(a ``non-capturing'' set of parentheses)
.TP
\fB()\fR
matches an empty string,
noted for possible reporting
.TP
\fB(?:)\fR
matches an empty string,
without reporting
.TP
\fB[\fIchars\fB]\fR
a \fIbracket expression\fR,
matching any one of the \fIchars\fR (see BRACKET EXPRESSIONS for more detail)
.TP
\fB.\fR
matches any single character
.TP
\fB\e\fIk\fR
(where \fIk\fR is a non-alphanumeric character)
matches that character taken as an ordinary character,
e.g. \e\e matches a backslash character
.TP
\fB\e\fIc\fR
where \fIc\fR is alphanumeric
(possibly followed by other characters),
an \fIescape\fR (AREs only),
see ESCAPES below
.TP
\fB{\fR
when followed by a character other than a digit,
matches the left-brace character `\fB{\fR';
when followed by a digit, it is the beginning of a
\fIbound\fR (see above)
.TP
\fIx\fR
where \fIx\fR is
a single character with no other significance, matches that character.
.RE
.PP
A \fIconstraint\fR matches an empty string when specific conditions
are met.
A constraint may not be followed by a quantifier.
The simple constraints are as follows; some more constraints are
described later, under ESCAPES.
.RS 2
.TP 8
\fB^\fR
matches at the beginning of a line
.TP
\fB$\fR
matches at the end of a line
.TP
\fB(?=\fIre\fB)\fR
\fIpositive lookahead\fR (AREs only), matches at any point
where a substring matching \fIre\fR begins
.TP
\fB(?!\fIre\fB)\fR
\fInegative lookahead\fR (AREs only), matches at any point
where no substring matching \fIre\fR begins
.RE
.PP
The lookahead constraints may not contain back references (see later),
and all parentheses within them are considered non-capturing.
.PP
An RE may not end with `\fB\e\fR'.
.SH "BRACKET EXPRESSIONS"
A \fIbracket expression\fR is a list of characters enclosed in `\fB[\|]\fR'.
It normally matches any single character from the list (but see below).
If the list begins with `\fB^\fR',
it matches any single character
(but see below) \fInot\fR from the rest of the list.
.PP
If two characters in the list are separated by `\fB\-\fR',
this is shorthand
for the full \fIrange\fR of characters between those two (inclusive) in the
collating sequence,
e.g.
\fB[0\-9]\fR
in ASCII matches any decimal digit.
Two ranges may not share an
endpoint, so e.g.
\fBa\-c\-e\fR
is illegal.
Ranges are very collating-sequence-dependent,
and portable programs should avoid relying on them.
.PP
To include a literal
\fB]\fR
or
\fB\-\fR
in the list,
the simplest method is to
enclose it in
\fB[.\fR and \fB.]\fR
to make it a collating element (see below).
Alternatively,
make it the first character
(following a possible `\fB^\fR'),
or (AREs only) precede it with `\fB\e\fR'.
Alternatively, for `\fB\-\fR',
make it the last character,
or the second endpoint of a range.
To use a literal
\fB\-\fR
as the first endpoint of a range,
make it a collating element
or (AREs only) precede it with `\fB\e\fR'.
With the exception of these, some combinations using
\fB[\fR
(see next
paragraphs), and escapes,
all other special characters lose their
special significance within a bracket expression.
.PP
Within a bracket expression, a collating element (a character,
a multi-character sequence that collates as if it were a single character,
or a collating-sequence name for either)
enclosed in
\fB[.\fR and \fB.]\fR
stands for the
sequence of characters of that collating element.
The sequence is a single element of the bracket expression's list.
A bracket expression in a locale that has
multi-character collating elements
can thus match more than one character.
.VS 8.2
So (insidiously), a bracket expression that starts with \fB^\fR
can match multi-character collating elements even if none of them
appear in the bracket expression!
(\fINote:\fR Tcl currently has no multi-character collating elements.
This information is only for illustration.)
.PP
For example, assume the collating sequence includes a \fBch\fR
multi-character collating element.
Then the RE \fB[[.ch.]]*c\fR (zero or more \fBch\fP's followed by \fBc\fP)
matches the first five characters of `\fBchchcc\fR'.
Also, the RE \fB[^c]b\fR matches all of `\fBchb\fR'
(because \fB[^c]\fR matches the multi-character \fBch\fR).
.VE 8.2
.PP
Within a bracket expression, a collating element enclosed in
\fB[=\fR
and
\fB=]\fR
is an equivalence class, standing for the sequences of characters
of all collating elements equivalent to that one, including itself.
(If there are no other equivalent collating elements,
the treatment is as if the enclosing delimiters were `\fB[.\fR'\&
and `\fB.]\fR'.)
For example, if
\fBo\fR
and
\fB\o'o^'\fR
are the members of an equivalence class,
then `\fB[[=o=]]\fR', `\fB[[=\o'o^'=]]\fR',
and `\fB[o\o'o^']\fR'\&
are all synonymous.
An equivalence class may not be an endpoint
of a range.
.VS 8.2
(\fINote:\fR
Tcl currently implements only the Unicode locale.
It doesn't define any equivalence classes.
The examples above are just illustrations.)
.VE 8.2
.PP
Within a bracket expression, the name of a \fIcharacter class\fR enclosed
in
\fB[:\fR
and
\fB:]\fR
stands for the list of all characters
(not all collating elements!)
belonging to that
class.
Standard character classes are:
.PP
.RS
.ne 5
.nf
.ta 3c
\fBalpha\fR A letter.
\fBupper\fR An upper-case letter.
\fBlower\fR A lower-case letter.
\fBdigit\fR A decimal digit.
\fBxdigit\fR A hexadecimal digit.
\fBalnum\fR An alphanumeric (letter or digit).
\fBprint\fR An alphanumeric (same as alnum).
\fBblank\fR A space or tab character.
\fBspace\fR A character producing white space in displayed text.
\fBpunct\fR A punctuation character.
\fBgraph\fR A character with a visible representation.
\fBcntrl\fR A control character.
.fi
.RE
.PP
A locale may provide others.
.VS 8.2
(Note that the current Tcl implementation has only one locale:
the Unicode locale.)
.VE 8.2
A character class may not be used as an endpoint of a range.
.PP
There are two special cases of bracket expressions:
the bracket expressions
\fB[[:<:]]\fR
and
\fB[[:>:]]\fR
are constraints, matching empty strings at
the beginning and end of a word respectively.
'\" note, discussion of escapes below references this definition of word
A word is defined as a sequence of
word characters
that is neither preceded nor followed by
word characters.
A word character is an
\fIalnum\fR
character
or an underscore
(\fB_\fR).
These special bracket expressions are deprecated;
users of AREs should use constraint escapes instead (see below).
.SH ESCAPES
Escapes (AREs only), which begin with a
\fB\e\fR
followed by an alphanumeric character,
come in several varieties:
character entry, class shorthands, constraint escapes, and back references.
A
\fB\e\fR
followed by an alphanumeric character but not constituting
a valid escape is illegal in AREs.
In EREs, there are no escapes:
outside a bracket expression,
a
\fB\e\fR
followed by an alphanumeric character merely stands for that
character as an ordinary character,
and inside a bracket expression,
\fB\e\fR
is an ordinary character.
(The latter is the one actual incompatibility between EREs and AREs.)
.PP
Character-entry escapes (AREs only) exist to make it easier to specify
non-printing and otherwise inconvenient characters in REs:
.RS 2
.TP 5
\fB\ea\fR
alert (bell) character, as in C
.TP
\fB\eb\fR
backspace, as in C
.TP
\fB\eB\fR
synonym for
\fB\e\fR
to help reduce backslash doubling in some
applications where there are multiple levels of backslash processing
.TP
\fB\ec\fIX\fR
(where X is any character) the character whose
low-order 5 bits are the same as those of
\fIX\fR,
and whose other bits are all zero
.TP
\fB\ee\fR
the character whose collating-sequence name
is `\fBESC\fR',
or failing that, the character with octal value 033
.TP
\fB\ef\fR
formfeed, as in C
.TP
\fB\en\fR
newline, as in C
.TP
\fB\er\fR
carriage return, as in C
.TP
\fB\et\fR
horizontal tab, as in C
.TP
\fB\eu\fIwxyz\fR
(where
\fIwxyz\fR
is exactly four hexadecimal digits)
the Unicode character
\fBU+\fIwxyz\fR
in the local byte ordering
.TP
\fB\eU\fIstuvwxyz\fR
(where
\fIstuvwxyz\fR
is exactly eight hexadecimal digits)
reserved for a somewhat-hypothetical Unicode extension to 32 bits
.TP
\fB\ev\fR
vertical tab, as in C
are all available.
.TP
\fB\ex\fIhhh\fR
(where
\fIhhh\fR
is any sequence of hexadecimal digits)
the character whose hexadecimal value is
\fB0x\fIhhh\fR
(a single character no matter how many hexadecimal digits are used).
.TP
\fB\e0\fR
the character whose value is
\fB0\fR
.TP
\fB\e\fIxy\fR
(where
\fIxy\fR
is exactly two octal digits,
and is not a
\fIback reference\fR (see below))
the character whose octal value is
\fB0\fIxy\fR
.TP
\fB\e\fIxyz\fR
(where
\fIxyz\fR
is exactly three octal digits,
and is not a
back reference (see below))
the character whose octal value is
\fB0\fIxyz\fR
.RE
.PP
Hexadecimal digits are `\fB0\fR'-`\fB9\fR', `\fBa\fR'-`\fBf\fR',
and `\fBA\fR'-`\fBF\fR'.
Octal digits are `\fB0\fR'-`\fB7\fR'.
.PP
The character-entry escapes are always taken as ordinary characters.
For example,
\fB\e135\fR
is
\fB]\fR
in ASCII,
but
\fB\e135\fR
does not terminate a bracket expression.
Beware, however, that some applications (e.g., C compilers) interpret
such sequences themselves before the regular-expression package
gets to see them, which may require doubling (quadrupling, etc.) the `\fB\e\fR'.
.PP
Class-shorthand escapes (AREs only) provide shorthands for certain commonly-used
character classes:
.RS 2
.TP 10
\fB\ed\fR
\fB[[:digit:]]\fR
.TP
\fB\es\fR
\fB[[:space:]]\fR
.TP
\fB\ew\fR
\fB[[:alnum:]_]\fR
(note underscore)
.TP
\fB\eD\fR
\fB[^[:digit:]]\fR
.TP
\fB\eS\fR
\fB[^[:space:]]\fR
.TP
\fB\eW\fR
\fB[^[:alnum:]_]\fR
(note underscore)
.RE
.PP
Within bracket expressions, `\fB\ed\fR', `\fB\es\fR',
and `\fB\ew\fR'\&
lose their outer brackets,
and `\fB\eD\fR', `\fB\eS\fR',
and `\fB\eW\fR'\&
are illegal.
.VS 8.2
(So, for example, \fB[a-c\ed]\fR is equivalent to \fB[a-c[:digit:]]\fR.
Also, \fB[a-c\eD]\fR, which is equivalent to \fB[a-c^[:digit:]]\fR, is illegal.)
.VE 8.2
.PP
A constraint escape (AREs only) is a constraint,
matching the empty string if specific conditions are met,
written as an escape:
.RS 2
.TP 6
\fB\eA\fR
matches only at the beginning of the string
(see MATCHING, below, for how this differs from `\fB^\fR')
.TP
\fB\em\fR
matches only at the beginning of a word
.TP
\fB\eM\fR
matches only at the end of a word
.TP
\fB\ey\fR
matches only at the beginning or end of a word
.TP
\fB\eY\fR
matches only at a point that is not the beginning or end of a word
.TP
\fB\eZ\fR
matches only at the end of the string
(see MATCHING, below, for how this differs from `\fB$\fR')
.TP
\fB\e\fIm\fR
(where
\fIm\fR
is a nonzero digit) a \fIback reference\fR, see below
.TP
\fB\e\fImnn\fR
(where
\fIm\fR
is a nonzero digit, and
\fInn\fR
is some more digits,
and the decimal value
\fImnn\fR
is not greater than the number of closing capturing parentheses seen so far)
a \fIback reference\fR, see below
.RE
.PP
A word is defined as in the specification of
\fB[[:<:]]\fR
and
\fB[[:>:]]\fR
above.
Constraint escapes are illegal within bracket expressions.
.PP
A back reference (AREs only) matches the same string matched by the parenthesized
subexpression specified by the number,
so that (e.g.)
\fB([bc])\e1\fR
matches
\fBbb\fR
or
\fBcc\fR
but not `\fBbc\fR'.
The subexpression must entirely precede the back reference in the RE.
Subexpressions are numbered in the order of their leading parentheses.
Non-capturing parentheses do not define subexpressions.
.PP
There is an inherent historical ambiguity between octal character-entry
escapes and back references, which is resolved by heuristics,
as hinted at above.
A leading zero always indicates an octal escape.
A single non-zero digit, not followed by another digit,
is always taken as a back reference.
A multi-digit sequence not starting with a zero is taken as a back
reference if it comes after a suitable subexpression
(i.e. the number is in the legal range for a back reference),
and otherwise is taken as octal.
.SH "METASYNTAX"
In addition to the main syntax described above, there are some special
forms and miscellaneous syntactic facilities available.
.PP
Normally the flavor of RE being used is specified by
application-dependent means.
However, this can be overridden by a \fIdirector\fR.
If an RE of any flavor begins with `\fB***:\fR',
the rest of the RE is an ARE.
If an RE of any flavor begins with `\fB***=\fR',
the rest of the RE is taken to be a literal string,
with all characters considered ordinary characters.
.PP
An ARE may begin with \fIembedded options\fR:
a sequence
\fB(?\fIxyz\fB)\fR
(where
\fIxyz\fR
is one or more alphabetic characters)
specifies options affecting the rest of the RE.
These supplement, and can override,
any options specified by the application.
The available option letters are:
.RS 2
.TP 3
\fBb\fR
rest of RE is a BRE
.TP 3
\fBc\fR
case-sensitive matching (usual default)
.TP 3
\fBe\fR
rest of RE is an ERE
.TP 3
\fBi\fR
case-insensitive matching (see MATCHING, below)
.TP 3
\fBm\fR
historical synonym for
\fBn\fR
.TP 3
\fBn\fR
newline-sensitive matching (see MATCHING, below)
.TP 3
\fBp\fR
partial newline-sensitive matching (see MATCHING, below)
.TP 3
\fBq\fR
rest of RE is a literal (``quoted'') string, all ordinary characters
.TP 3
\fBs\fR
non-newline-sensitive matching (usual default)
.TP 3
\fBt\fR
tight syntax (usual default; see below)
.TP 3
\fBw\fR
inverse partial newline-sensitive (``weird'') matching (see MATCHING, below)
.TP 3
\fBx\fR
expanded syntax (see below)
.RE
.PP
Embedded options take effect at the
\fB)\fR
terminating the sequence.
They are available only at the start of an ARE,
and may not be used later within it.
.PP
In addition to the usual (\fItight\fR) RE syntax, in which all characters are
significant, there is an \fIexpanded\fR syntax,
available in all flavors of RE
with the \fB-expanded\fR switch, or in AREs with the embedded x option.
In the expanded syntax,
white-space characters are ignored
and all characters between a
\fB#\fR
and the following newline (or the end of the RE) are ignored,
permitting paragraphing and commenting a complex RE.
There are three exceptions to that basic rule:
.RS 2
.PP
a white-space character or `\fB#\fR' preceded by `\fB\e\fR' is retained
.PP
white space or `\fB#\fR' within a bracket expression is retained
.PP
white space and comments are illegal within multi-character symbols
like the ARE `\fB(?:\fR' or the BRE `\fB\e(\fR'
.RE
.PP
Expanded-syntax white-space characters are blank, tab, newline, and
.VS 8.2
any character that belongs to the \fIspace\fR character class.
.VE 8.2
.PP
Finally, in an ARE,
outside bracket expressions, the sequence `\fB(?#\fIttt\fB)\fR'
(where
\fIttt\fR
is any text not containing a `\fB)\fR')
is a comment,
completely ignored.
Again, this is not allowed between the characters of
multi-character symbols like `\fB(?:\fR'.
Such comments are more a historical artifact than a useful facility,
and their use is deprecated;
use the expanded syntax instead.
.PP
\fINone\fR of these metasyntax extensions is available if the application
(or an initial
\fB***=\fR
director)
has specified that the user's input be treated as a literal string
rather than as an RE.
.SH MATCHING
In the event that an RE could match more than one substring of a given
string,
the RE matches the one starting earliest in the string.
If the RE could match more than one substring starting at that point,
its choice is determined by its \fIpreference\fR:
either the longest substring, or the shortest.
.PP
Most atoms, and all constraints, have no preference.
A parenthesized RE has the same preference (possibly none) as the RE.
A quantified atom with quantifier
\fB{\fIm\fB}\fR
or
\fB{\fIm\fB}?\fR
has the same preference (possibly none) as the atom itself.
A quantified atom with other normal quantifiers (including
\fB{\fIm\fB,\fIn\fB}\fR
with
\fIm\fR
equal to
\fIn\fR)
prefers longest match.
A quantified atom with other non-greedy quantifiers (including
\fB{\fIm\fB,\fIn\fB}?\fR
with
\fIm\fR
equal to
\fIn\fR)
prefers shortest match.
A branch has the same preference as the first quantified atom in it
which has a preference.
An RE consisting of two or more branches connected by the
\fB|\fR
operator prefers longest match.
.PP
Subject to the constraints imposed by the rules for matching the whole RE,
subexpressions also match the longest or shortest possible substrings,
based on their preferences,
with subexpressions starting earlier in the RE taking priority over
ones starting later.
Note that outer subexpressions thus take priority over
their component subexpressions.
.PP
Note that the quantifiers
\fB{1,1}\fR
and
\fB{1,1}?\fR
can be used to force longest and shortest preference, respectively,
on a subexpression or a whole RE.
.PP
Match lengths are measured in characters, not collating elements.
An empty string is considered longer than no match at all.
For example,
\fBbb*\fR
matches the three middle characters of `\fBabbbc\fR',
\fB(week|wee)(night|knights)\fR
matches all ten characters of `\fBweeknights\fR',
when
\fB(.*).*\fR
is matched against
\fBabc\fR
the parenthesized subexpression
matches all three characters, and
when
\fB(a*)*\fR
is matched against
\fBbc\fR
both the whole RE and the parenthesized
subexpression match an empty string.
.PP
If case-independent matching is specified,
the effect is much as if all case distinctions had vanished from the
alphabet.
When an alphabetic that exists in multiple cases appears as an
ordinary character outside a bracket expression, it is effectively
transformed into a bracket expression containing both cases,
so that
\fBx\fR
becomes `\fB[xX]\fR'.
When it appears inside a bracket expression, all case counterparts
of it are added to the bracket expression, so that
\fB[x]\fR
becomes
\fB[xX]\fR
and
\fB[^x]\fR
becomes `\fB[^xX]\fR'.
.PP
If newline-sensitive matching is specified, \fB.\fR
and bracket expressions using
\fB^\fR
will never match the newline character
(so that matches will never cross newlines unless the RE
explicitly arranges it)
and
\fB^\fR
and
\fB$\fR
will match the empty string after and before a newline
respectively, in addition to matching at beginning and end of string
respectively.
ARE
\fB\eA\fR
and
\fB\eZ\fR
continue to match beginning or end of string \fIonly\fR.
.PP
If partial newline-sensitive matching is specified,
this affects \fB.\fR
and bracket expressions
as with newline-sensitive matching, but not
\fB^\fR
and `\fB$\fR'.
.PP
If inverse partial newline-sensitive matching is specified,
this affects
\fB^\fR
and
\fB$\fR
as with
newline-sensitive matching,
but not \fB.\fR
and bracket expressions.
This isn't very useful but is provided for symmetry.
.SH "LIMITS AND COMPATIBILITY"
No particular limit is imposed on the length of REs.
Programs intended to be highly portable should not employ REs longer
than 256 bytes,
as a POSIX-compliant implementation can refuse to accept such REs.
.PP
The only feature of AREs that is actually incompatible with
POSIX EREs is that
\fB\e\fR
does not lose its special
significance inside bracket expressions.
All other ARE features use syntax which is illegal or has
undefined or unspecified effects in POSIX EREs;
the
\fB***\fR
syntax of directors likewise is outside the POSIX
syntax for both BREs and EREs.
.PP
Many of the ARE extensions are borrowed from Perl, but some have
been changed to clean them up, and a few Perl extensions are not present.
Incompatibilities of note include `\fB\eb\fR', `\fB\eB\fR',
the lack of special treatment for a trailing newline,
the addition of complemented bracket expressions to the things
affected by newline-sensitive matching,
the restrictions on parentheses and back references in lookahead constraints,
and the longest/shortest-match (rather than first-match) matching semantics.
.PP
The matching rules for REs containing both normal and non-greedy quantifiers
have changed since early beta-test versions of this package.
(The new rules are much simpler and cleaner,
but don't work as hard at guessing the user's real intentions.)
.PP
Henry Spencer's original 1986 \fIregexp\fR package,
still in widespread use (e.g., in pre-8.1 releases of Tcl),
implemented an early version of today's EREs.
There are four incompatibilities between \fIregexp\fR's near-EREs
(`RREs' for short) and AREs.
In roughly increasing order of significance:
.PP
.RS
In AREs,
\fB\e\fR
followed by an alphanumeric character is either an
escape or an error,
while in RREs, it was just another way of writing the
alphanumeric.
This should not be a problem because there was no reason to write
such a sequence in RREs.
.PP
\fB{\fR
followed by a digit in an ARE is the beginning of a bound,
while in RREs,
\fB{\fR
was always an ordinary character.
Such sequences should be rare,
and will often result in an error because following characters
will not look like a valid bound.
.PP
In AREs,
\fB\e\fR
remains a special character within `\fB[\|]\fR',
so a literal
\fB\e\fR
within
\fB[\|]\fR
must be written `\fB\e\e\fR'.
\fB\e\e\fR
also gives a literal
\fB\e\fR
within
\fB[\|]\fR
in RREs,
but only truly paranoid programmers routinely doubled the backslash.
.PP
AREs report the longest/shortest match for the RE,
rather than the first found in a specified search order.
This may affect some RREs which were written in the expectation that
the first match would be reported.
(The careful crafting of RREs to optimize the search order for fast
matching is obsolete (AREs examine all possible matches
in parallel, and their performance is largely insensitive to their
complexity) but cases where the search order was exploited to deliberately
find a match which was \fInot\fR the longest/shortest will need rewriting.)
.RE
.SH "BASIC REGULAR EXPRESSIONS"
BREs differ from EREs in several respects. `\fB|\fR', `\fB+\fR',
and
\fB?\fR
are ordinary characters and there is no equivalent
for their functionality.
The delimiters for bounds are
\fB\e{\fR
and `\fB\e}\fR',
with
\fB{\fR
and
\fB}\fR
by themselves ordinary characters.
The parentheses for nested subexpressions are
\fB\e(\fR
and `\fB\e)\fR',
with
\fB(\fR
and
\fB)\fR
by themselves ordinary characters.
\fB^\fR
is an ordinary character except at the beginning of the
RE or the beginning of a parenthesized subexpression,
\fB$\fR
is an ordinary character except at the end of the
RE or the end of a parenthesized subexpression,
and
\fB*\fR
is an ordinary character if it appears at the beginning of the
RE or the beginning of a parenthesized subexpression
(after a possible leading `\fB^\fR').
Finally,
single-digit back references are available,
and
\fB\e<\fR
and
\fB\e>\fR
are synonyms for
\fB[[:<:]]\fR
and
\fB[[:>:]]\fR
respectively;
no other escapes are available.
.SH "SEE ALSO"
RegExp(3), regexp(n), regsub(n), lsearch(n), switch(n), text(n)
.SH KEYWORDS
match, regular expression, string
src/backend/regex/regc_color.c 0 → 100644
View file @ 7bcc6d98
/*
* colorings of characters
* This file is #included by regcomp.c.
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Header: /cvsroot/pgsql/src/backend/regex/regc_color.c,v 1.1 2003/02/05 17:41:32 tgl Exp $
*
*
* Note that there are some incestuous relationships between this code and
* NFA arc maintenance, which perhaps ought to be cleaned up sometime.
*/
#define CISERR() VISERR(cm->v)
#define CERR(e) VERR(cm->v, (e))
/*
* initcm - set up new colormap
*/
static void
initcm(struct vars *v,
struct colormap *cm)
{
int i;
int j;
union tree *t;
union tree *nextt;
struct colordesc *cd;
cm->magic = CMMAGIC;
cm->v = v;
cm->ncds = NINLINECDS;
cm->cd = cm->cdspace;
cm->max = 0;
cm->free = 0;
cd = cm->cd; /* cm->cd[WHITE] */
cd->sub = NOSUB;
cd->arcs = NULL;
cd->flags = 0;
cd->nchrs = CHR_MAX - CHR_MIN + 1;
/* upper levels of tree */
for (t = &cm->tree[0], j = NBYTS-1; j > 0; t = nextt, j--) {
nextt = t + 1;
for (i = BYTTAB-1; i >= 0; i--)
t->tptr[i] = nextt;
}
/* bottom level is solid white */
t = &cm->tree[NBYTS-1];
for (i = BYTTAB-1; i >= 0; i--)
t->tcolor[i] = WHITE;
cd->block = t;
}
/*
* freecm - free dynamically-allocated things in a colormap
*/
static void
freecm(struct colormap *cm)
{
size_t i;
union tree *cb;
cm->magic = 0;
if (NBYTS > 1)
cmtreefree(cm, cm->tree, 0);
for (i = 1; i <= cm->max; i++) /* skip WHITE */
if (!UNUSEDCOLOR(&cm->cd[i])) {
cb = cm->cd[i].block;
if (cb != NULL)
FREE(cb);
}
if (cm->cd != cm->cdspace)
FREE(cm->cd);
}
/*
* cmtreefree - free a non-terminal part of a colormap tree
*/
static void
cmtreefree(struct colormap *cm,
union tree *tree,
int level) /* level number (top == 0) of this block */
{
int i;
union tree *t;
union tree *fillt = &cm->tree[level+1];
union tree *cb;
assert(level < NBYTS-1); /* this level has pointers */
for (i = BYTTAB-1; i >= 0; i--) {
t = tree->tptr[i];
assert(t != NULL);
if (t != fillt) {
if (level < NBYTS-2) { /* more pointer blocks below */
cmtreefree(cm, t, level+1);
FREE(t);
} else { /* color block below */
cb = cm->cd[t->tcolor[0]].block;
if (t != cb) /* not a solid block */
FREE(t);
}
}
}
}
/*
* setcolor - set the color of a character in a colormap
*/
static color /* previous color */
setcolor(struct colormap *cm,
chr c,
pcolor co)
{
uchr uc = c;
int shift;
int level;
int b;
int bottom;
union tree *t;
union tree *newt;
union tree *fillt;
union tree *lastt;
union tree *cb;
color prev;
assert(cm->magic == CMMAGIC);
if (CISERR() || co == COLORLESS)
return COLORLESS;
t = cm->tree;
for (level = 0, shift = BYTBITS * (NBYTS - 1); shift > 0;
level++, shift -= BYTBITS) {
b = (uc >> shift) & BYTMASK;
lastt = t;
t = lastt->tptr[b];
assert(t != NULL);
fillt = &cm->tree[level+1];
bottom = (shift <= BYTBITS) ? 1 : 0;
cb = (bottom) ? cm->cd[t->tcolor[0]].block : fillt;
if (t == fillt || t == cb) { /* must allocate a new block */
newt = (union tree *)MALLOC((bottom) ?
sizeof(struct colors) : sizeof(struct ptrs));
if (newt == NULL) {
CERR(REG_ESPACE);
return COLORLESS;
}
if (bottom)
memcpy(VS(newt->tcolor), VS(t->tcolor),
BYTTAB*sizeof(color));
else
memcpy(VS(newt->tptr), VS(t->tptr),
BYTTAB*sizeof(union tree *));
t = newt;
lastt->tptr[b] = t;
}
}
b = uc & BYTMASK;
prev = t->tcolor[b];
t->tcolor[b] = (color)co;
return prev;
}
/*
* maxcolor - report largest color number in use
*/
static color
maxcolor(struct colormap *cm)
{
if (CISERR())
return COLORLESS;
return (color)cm->max;
}
/*
* newcolor - find a new color (must be subject of setcolor at once)
* Beware: may relocate the colordescs.
*/
static color /* COLORLESS for error */
newcolor(struct colormap *cm)
{
struct colordesc *cd;
struct colordesc *new;
size_t n;
if (CISERR())
return COLORLESS;
if (cm->free != 0) {
assert(cm->free > 0);
assert((size_t)cm->free < cm->ncds);
cd = &cm->cd[cm->free];
assert(UNUSEDCOLOR(cd));
assert(cd->arcs == NULL);
cm->free = cd->sub;
} else if (cm->max < cm->ncds - 1) {
cm->max++;
cd = &cm->cd[cm->max];
} else {
/* oops, must allocate more */
n = cm->ncds * 2;
if (cm->cd == cm->cdspace) {
new = (struct colordesc *)MALLOC(n *
sizeof(struct colordesc));
if (new != NULL)
memcpy(VS(new), VS(cm->cdspace), cm->ncds *
sizeof(struct colordesc));
} else
new = (struct colordesc *)REALLOC(cm->cd,
n * sizeof(struct colordesc));
if (new == NULL) {
CERR(REG_ESPACE);
return COLORLESS;
}
cm->cd = new;
cm->ncds = n;
assert(cm->max < cm->ncds - 1);
cm->max++;
cd = &cm->cd[cm->max];
}
cd->nchrs = 0;
cd->sub = NOSUB;
cd->arcs = NULL;
cd->flags = 0;
cd->block = NULL;
return (color)(cd - cm->cd);
}
/*
* freecolor - free a color (must have no arcs or subcolor)
*/
static void
freecolor(struct colormap *cm,
pcolor co)
{
struct colordesc *cd = &cm->cd[co];
color pco, nco; /* for freelist scan */
assert(co >= 0);
if (co == WHITE)
return;
assert(cd->arcs == NULL);
assert(cd->sub == NOSUB);
assert(cd->nchrs == 0);
cd->flags = FREECOL;
if (cd->block != NULL) {
FREE(cd->block);
cd->block = NULL; /* just paranoia */
}
if ((size_t)co == cm->max) {
while (cm->max > WHITE && UNUSEDCOLOR(&cm->cd[cm->max]))
cm->max--;
assert(cm->free >= 0);
while ((size_t)cm->free > cm->max)
cm->free = cm->cd[cm->free].sub;
if (cm->free > 0) {
assert(cm->free < cm->max);
pco = cm->free;
nco = cm->cd[pco].sub;
while (nco > 0)
if ((size_t)nco > cm->max) {
/* take this one out of freelist */
nco = cm->cd[nco].sub;
cm->cd[pco].sub = nco;
} else {
assert(nco < cm->max);
pco = nco;
nco = cm->cd[pco].sub;
}
}
} else {
cd->sub = cm->free;
cm->free = (color)(cd - cm->cd);
}
}
/*
* pseudocolor - allocate a false color, to be managed by other means
*/
static color
pseudocolor(struct colormap *cm)
{
color co;
co = newcolor(cm);
if (CISERR())
return COLORLESS;
cm->cd[co].nchrs = 1;
cm->cd[co].flags = PSEUDO;
return co;
}
/*
* subcolor - allocate a new subcolor (if necessary) to this chr
*/
static color
subcolor(struct colormap *cm, chr c)
{
color co; /* current color of c */
color sco; /* new subcolor */
co = GETCOLOR(cm, c);
sco = newsub(cm, co);
if (CISERR())
return COLORLESS;
assert(sco != COLORLESS);
if (co == sco) /* already in an open subcolor */
return co; /* rest is redundant */
cm->cd[co].nchrs--;
cm->cd[sco].nchrs++;
setcolor(cm, c, sco);
return sco;
}
/*
* newsub - allocate a new subcolor (if necessary) for a color
*/
static color
newsub(struct colormap *cm,
pcolor co)
{
color sco; /* new subcolor */
sco = cm->cd[co].sub;
if (sco == NOSUB) { /* color has no open subcolor */
if (cm->cd[co].nchrs == 1) /* optimization */
return co;
sco = newcolor(cm); /* must create subcolor */
if (sco == COLORLESS) {
assert(CISERR());
return COLORLESS;
}
cm->cd[co].sub = sco;
cm->cd[sco].sub = sco; /* open subcolor points to self */
}
assert(sco != NOSUB);
return sco;
}
/*
* subrange - allocate new subcolors to this range of chrs, fill in arcs
*/
static void
subrange(struct vars *v,
chr from,
chr to,
struct state *lp,
struct state *rp)
{
uchr uf;
int i;
assert(from <= to);
/* first, align "from" on a tree-block boundary */
uf = (uchr)from;
i = (int)( ((uf + BYTTAB-1) & (uchr)~BYTMASK) - uf );
for (; from <= to && i > 0; i--, from++)
newarc(v->nfa, PLAIN, subcolor(v->cm, from), lp, rp);
if (from > to) /* didn't reach a boundary */
return;
/* deal with whole blocks */
for (; to - from >= BYTTAB; from += BYTTAB)
subblock(v, from, lp, rp);
/* clean up any remaining partial table */
for (; from <= to; from++)
newarc(v->nfa, PLAIN, subcolor(v->cm, from), lp, rp);
}
/*
* subblock - allocate new subcolors for one tree block of chrs, fill in arcs
*/
static void
subblock(struct vars *v,
chr start, /* first of BYTTAB chrs */
struct state *lp,
struct state *rp)
{
uchr uc = start;
struct colormap *cm = v->cm;
int shift;
int level;
int i;
int b;
union tree *t;
union tree *cb;
union tree *fillt;
union tree *lastt;
int previ;
int ndone;
color co;
color sco;
assert((uc % BYTTAB) == 0);
/* find its color block, making new pointer blocks as needed */
t = cm->tree;
fillt = NULL;
for (level = 0, shift = BYTBITS * (NBYTS - 1); shift > 0;
level++, shift -= BYTBITS) {
b = (uc >> shift) & BYTMASK;
lastt = t;
t = lastt->tptr[b];
assert(t != NULL);
fillt = &cm->tree[level+1];
if (t == fillt && shift > BYTBITS) { /* need new ptr block */
t = (union tree *)MALLOC(sizeof(struct ptrs));
if (t == NULL) {
CERR(REG_ESPACE);
return;
}
memcpy(VS(t->tptr), VS(fillt->tptr),
BYTTAB*sizeof(union tree *));
lastt->tptr[b] = t;
}
}
/* special cases: fill block or solid block */
co = t->tcolor[0];
cb = cm->cd[co].block;
if (t == fillt || t == cb) {
/* either way, we want a subcolor solid block */
sco = newsub(cm, co);
t = cm->cd[sco].block;
if (t == NULL) { /* must set it up */
t = (union tree *)MALLOC(sizeof(struct colors));
if (t == NULL) {
CERR(REG_ESPACE);
return;
}
for (i = 0; i < BYTTAB; i++)
t->tcolor[i] = sco;
cm->cd[sco].block = t;
}
/* find loop must have run at least once */
lastt->tptr[b] = t;
newarc(v->nfa, PLAIN, sco, lp, rp);
cm->cd[co].nchrs -= BYTTAB;
cm->cd[sco].nchrs += BYTTAB;
return;
}
/* general case, a mixed block to be altered */
i = 0;
while (i < BYTTAB) {
co = t->tcolor[i];
sco = newsub(cm, co);
newarc(v->nfa, PLAIN, sco, lp, rp);
previ = i;
do {
t->tcolor[i++] = sco;
} while (i < BYTTAB && t->tcolor[i] == co);
ndone = i - previ;
cm->cd[co].nchrs -= ndone;
cm->cd[sco].nchrs += ndone;
}
}
/*
* okcolors - promote subcolors to full colors
*/
static void
okcolors(struct nfa *nfa,
struct colormap *cm)
{
struct colordesc *cd;
struct colordesc *end = CDEND(cm);
struct colordesc *scd;
struct arc *a;
color co;
color sco;
for (cd = cm->cd, co = 0; cd < end; cd++, co++) {
sco = cd->sub;
if (UNUSEDCOLOR(cd) || sco == NOSUB) {
/* has no subcolor, no further action */
} else if (sco == co) {
/* is subcolor, let parent deal with it */
} else if (cd->nchrs == 0) {
/* parent empty, its arcs change color to subcolor */
cd->sub = NOSUB;
scd = &cm->cd[sco];
assert(scd->nchrs > 0);
assert(scd->sub == sco);
scd->sub = NOSUB;
while ((a = cd->arcs) != NULL) {
assert(a->co == co);
/* uncolorchain(cm, a); */
cd->arcs = a->colorchain;
a->co = sco;
/* colorchain(cm, a); */
a->colorchain = scd->arcs;
scd->arcs = a;
}
freecolor(cm, co);
} else {
/* parent's arcs must gain parallel subcolor arcs */
cd->sub = NOSUB;
scd = &cm->cd[sco];
assert(scd->nchrs > 0);
assert(scd->sub == sco);
scd->sub = NOSUB;
for (a = cd->arcs; a != NULL; a = a->colorchain) {
assert(a->co == co);
newarc(nfa, a->type, sco, a->from, a->to);
}
}
}
}
/*
* colorchain - add this arc to the color chain of its color
*/
static void
colorchain(struct colormap *cm,
struct arc *a)
{
struct colordesc *cd = &cm->cd[a->co];
a->colorchain = cd->arcs;
cd->arcs = a;
}
/*
* uncolorchain - delete this arc from the color chain of its color
*/
static void
uncolorchain(struct colormap *cm,
struct arc *a)
{
struct colordesc *cd = &cm->cd[a->co];
struct arc *aa;
aa = cd->arcs;
if (aa == a) /* easy case */
cd->arcs = a->colorchain;
else {
for (; aa != NULL && aa->colorchain != a; aa = aa->colorchain)
continue;
assert(aa != NULL);
aa->colorchain = a->colorchain;
}
a->colorchain = NULL; /* paranoia */
}
/*
* singleton - is this character in its own color?
*/
static int /* predicate */
singleton(struct colormap *cm,
chr c)
{
color co; /* color of c */
co = GETCOLOR(cm, c);
if (cm->cd[co].nchrs == 1 && cm->cd[co].sub == NOSUB)
return 1;
return 0;
}
/*
* rainbow - add arcs of all full colors (but one) between specified states
*/
static void
rainbow(struct nfa *nfa,
struct colormap *cm,
int type,
pcolor but, /* COLORLESS if no exceptions */
struct state *from,
struct state *to)
{
struct colordesc *cd;
struct colordesc *end = CDEND(cm);
color co;
for (cd = cm->cd, co = 0; cd < end && !CISERR(); cd++, co++)
if (!UNUSEDCOLOR(cd) && cd->sub != co && co != but &&
!(cd->flags&PSEUDO))
newarc(nfa, type, co, from, to);
}
/*
* colorcomplement - add arcs of complementary colors
*
* The calling sequence ought to be reconciled with cloneouts().
*/
static void
colorcomplement(struct nfa *nfa,
struct colormap *cm,
int type,
struct state *of, /* complements of this guy's PLAIN outarcs */
struct state *from,
struct state *to)
{
struct colordesc *cd;
struct colordesc *end = CDEND(cm);
color co;
assert(of != from);
for (cd = cm->cd, co = 0; cd < end && !CISERR(); cd++, co++)
if (!UNUSEDCOLOR(cd) && !(cd->flags&PSEUDO))
if (findarc(of, PLAIN, co) == NULL)
newarc(nfa, type, co, from, to);
}
#ifdef REG_DEBUG
/*
* dumpcolors - debugging output
*/
static void
dumpcolors(struct colormap *cm,
FILE *f)
{
struct colordesc *cd;
struct colordesc *end;
color co;
chr c;
char *has;
fprintf(f, "max %ld\n", (long)cm->max);
if (NBYTS > 1)
fillcheck(cm, cm->tree, 0, f);
end = CDEND(cm);
for (cd = cm->cd + 1, co = 1; cd < end; cd++, co++) /* skip 0 */
if (!UNUSEDCOLOR(cd)) {
assert(cd->nchrs > 0);
has = (cd->block != NULL) ? "#" : "";
if (cd->flags&PSEUDO)
fprintf(f, "#%2ld%s(ps): ", (long)co, has);
else
fprintf(f, "#%2ld%s(%2d): ", (long)co,
has, cd->nchrs);
/* it's hard to do this more efficiently */
for (c = CHR_MIN; c < CHR_MAX; c++)
if (GETCOLOR(cm, c) == co)
dumpchr(c, f);
assert(c == CHR_MAX);
if (GETCOLOR(cm, c) == co)
dumpchr(c, f);
fprintf(f, "\n");
}
}
/*
* fillcheck - check proper filling of a tree
*/
static void
fillcheck(struct colormap *cm,
union tree *tree,
int level, /* level number (top == 0) of this block */
FILE *f)
{
int i;
union tree *t;
union tree *fillt = &cm->tree[level+1];
assert(level < NBYTS-1); /* this level has pointers */
for (i = BYTTAB-1; i >= 0; i--) {
t = tree->tptr[i];
if (t == NULL)
fprintf(f, "NULL found in filled tree!\n");
else if (t == fillt)
{}
else if (level < NBYTS-2) /* more pointer blocks below */
fillcheck(cm, t, level+1, f);
}
}
/*
* dumpchr - print a chr
*
* Kind of char-centric but works well enough for debug use.
*/
static void
dumpchr(chr c,
FILE *f)
{
if (c == '\\')
fprintf(f, "\\\\");
else if (c > ' ' && c <= '~')
putc((char)c, f);
else
fprintf(f, "\\u%04lx", (long)c);
}
#endif /* REG_DEBUG */
src/backend/regex/regc_cvec.c 0 → 100644
View file @ 7bcc6d98
/*
* Utility functions for handling cvecs
* This file is #included by regcomp.c.
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Header: /cvsroot/pgsql/src/backend/regex/regc_cvec.c,v 1.1 2003/02/05 17:41:32 tgl Exp $
*
*/
/*
* newcvec - allocate a new cvec
*/
static struct cvec *
newcvec(int nchrs, /* to hold this many chrs... */
int nranges, /* ... and this many ranges... */
int nmcces) /* ... and this many MCCEs */
{
size_t n;
size_t nc;
struct cvec *cv;
nc = (size_t)nchrs + (size_t)nmcces*(MAXMCCE+1) + (size_t)nranges*2;
n = sizeof(struct cvec) + (size_t)(nmcces-1)*sizeof(chr *)
+ nc*sizeof(chr);
cv = (struct cvec *)MALLOC(n);
if (cv == NULL) {
return NULL;
}
cv->chrspace = nchrs;
cv->chrs = (chr *)&cv->mcces[nmcces]; /* chrs just after MCCE ptrs */
cv->mccespace = nmcces;
cv->ranges = cv->chrs + nchrs + nmcces*(MAXMCCE+1);
cv->rangespace = nranges;
return clearcvec(cv);
}
/*
* clearcvec - clear a possibly-new cvec
* Returns pointer as convenience.
*/
static struct cvec *
clearcvec(struct cvec *cv)
{
int i;
assert(cv != NULL);
cv->nchrs = 0;
assert(cv->chrs == (chr *)&cv->mcces[cv->mccespace]);
cv->nmcces = 0;
cv->nmccechrs = 0;
cv->nranges = 0;
for (i = 0; i < cv->mccespace; i++) {
cv->mcces[i] = NULL;
}
return cv;
}
/*
* addchr - add a chr to a cvec
*/
static void
addchr(struct cvec *cv, /* character vector */
chr c) /* character to add */
{
assert(cv->nchrs < cv->chrspace - cv->nmccechrs);
cv->chrs[cv->nchrs++] = (chr)c;
}
/*
* addrange - add a range to a cvec
*/
static void
addrange(struct cvec *cv, /* character vector */
chr from, /* first character of range */
chr to) /* last character of range */
{
assert(cv->nranges < cv->rangespace);
cv->ranges[cv->nranges*2] = (chr)from;
cv->ranges[cv->nranges*2 + 1] = (chr)to;
cv->nranges++;
}
/*
* addmcce - add an MCCE to a cvec
*/
static void
addmcce(struct cvec *cv, /* character vector */
chr *startp, /* beginning of text */
chr *endp) /* just past end of text */
{
int len;
int i;
chr *s;
chr *d;
if (startp == NULL && endp == NULL) {
return;
}
len = endp - startp;
assert(len > 0);
assert(cv->nchrs + len < cv->chrspace - cv->nmccechrs);
assert(cv->nmcces < cv->mccespace);
d = &cv->chrs[cv->chrspace - cv->nmccechrs - len - 1];
cv->mcces[cv->nmcces++] = d;
for (s = startp, i = len; i > 0; s++, i--) {
*d++ = *s;
}
*d++ = 0; /* endmarker */
assert(d == &cv->chrs[cv->chrspace - cv->nmccechrs]);
cv->nmccechrs += len + 1;
}
/*
* haschr - does a cvec contain this chr?
*/
static int /* predicate */
haschr(struct cvec *cv, /* character vector */
chr c) /* character to test for */
{
int i;
chr *p;
for (p = cv->chrs, i = cv->nchrs; i > 0; p++, i--) {
if (*p == c) {
return 1;
}
}
for (p = cv->ranges, i = cv->nranges; i > 0; p += 2, i--) {
if ((*p <= c) && (c <= *(p+1))) {
return 1;
}
}
return 0;
}
/*
* getcvec - get a cvec, remembering it as v->cv
*/
static struct cvec *
getcvec(struct vars *v, /* context */
int nchrs, /* to hold this many chrs... */
int nranges, /* ... and this many ranges... */
int nmcces) /* ... and this many MCCEs */
{
if (v->cv != NULL && nchrs <= v->cv->chrspace &&
nranges <= v->cv->rangespace && nmcces <= v->cv->mccespace) {
return clearcvec(v->cv);
}
if (v->cv != NULL) {
freecvec(v->cv);
}
v->cv = newcvec(nchrs, nranges, nmcces);
if (v->cv == NULL) {
ERR(REG_ESPACE);
}
return v->cv;
}
/*
* freecvec - free a cvec
*/
static void
freecvec(struct cvec *cv)
{
FREE(cv);
}
src/backend/regex/regc_lex.c 0 → 100644
View file @ 7bcc6d98
/*
* lexical analyzer
* This file is #included by regcomp.c.
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Header: /cvsroot/pgsql/src/backend/regex/regc_lex.c,v 1.1 2003/02/05 17:41:32 tgl Exp $
*
*/
/* scanning macros (know about v) */
#define ATEOS() (v->now >= v->stop)
#define HAVE(n) (v->stop - v->now >= (n))
#define NEXT1(c) (!ATEOS() && *v->now == CHR(c))
#define NEXT2(a,b) (HAVE(2) && *v->now == CHR(a) && *(v->now+1) == CHR(b))
#define NEXT3(a,b,c) (HAVE(3) && *v->now == CHR(a) && \
*(v->now+1) == CHR(b) && \
*(v->now+2) == CHR(c))
#define SET(c) (v->nexttype = (c))
#define SETV(c, n) (v->nexttype = (c), v->nextvalue = (n))
#define RET(c) return (SET(c), 1)
#define RETV(c, n) return (SETV(c, n), 1)
#define FAILW(e) return (ERR(e), 0) /* ERR does SET(EOS) */
#define LASTTYPE(t) (v->lasttype == (t))
/* lexical contexts */
#define L_ERE 1 /* mainline ERE/ARE */
#define L_BRE 2 /* mainline BRE */
#define L_Q 3 /* REG_QUOTE */
#define L_EBND 4 /* ERE/ARE bound */
#define L_BBND 5 /* BRE bound */
#define L_BRACK 6 /* brackets */
#define L_CEL 7 /* collating element */
#define L_ECL 8 /* equivalence class */
#define L_CCL 9 /* character class */
#define INTOCON(c) (v->lexcon = (c))
#define INCON(con) (v->lexcon == (con))
/* construct pointer past end of chr array */
#define ENDOF(array) ((array) + sizeof(array)/sizeof(chr))
/*
* lexstart - set up lexical stuff, scan leading options
*/
static void
lexstart(struct vars *v)
{
prefixes(v); /* may turn on new type bits etc. */
NOERR();
if (v->cflags&REG_QUOTE) {
assert(!(v->cflags&(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE)));
INTOCON(L_Q);
} else if (v->cflags&REG_EXTENDED) {
assert(!(v->cflags&REG_QUOTE));
INTOCON(L_ERE);
} else {
assert(!(v->cflags&(REG_QUOTE|REG_ADVF)));
INTOCON(L_BRE);
}
v->nexttype = EMPTY; /* remember we were at the start */
next(v); /* set up the first token */
}
/*
* prefixes - implement various special prefixes
*/
static void
prefixes(struct vars *v)
{
/* literal string doesn't get any of this stuff */
if (v->cflags&REG_QUOTE)
return;
/* initial "***" gets special things */
if (HAVE(4) && NEXT3('*', '*', '*'))
switch (*(v->now + 3)) {
case CHR('?'): /* "***?" error, msg shows version */
ERR(REG_BADPAT);
return; /* proceed no further */
break;
case CHR('='): /* "***=" shifts to literal string */
NOTE(REG_UNONPOSIX);
v->cflags |= REG_QUOTE;
v->cflags &= ~(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE);
v->now += 4;
return; /* and there can be no more prefixes */
break;
case CHR(':'): /* "***:" shifts to AREs */
NOTE(REG_UNONPOSIX);
v->cflags |= REG_ADVANCED;
v->now += 4;
break;
default: /* otherwise *** is just an error */
ERR(REG_BADRPT);
return;
break;
}
/* BREs and EREs don't get embedded options */
if ((v->cflags&REG_ADVANCED) != REG_ADVANCED)
return;
/* embedded options (AREs only) */
if (HAVE(3) && NEXT2('(', '?') && iscalpha(*(v->now + 2))) {
NOTE(REG_UNONPOSIX);
v->now += 2;
for (; !ATEOS() && iscalpha(*v->now); v->now++)
switch (*v->now) {
case CHR('b'): /* BREs (but why???) */
v->cflags &= ~(REG_ADVANCED|REG_QUOTE);
break;
case CHR('c'): /* case sensitive */
v->cflags &= ~REG_ICASE;
break;
case CHR('e'): /* plain EREs */
v->cflags |= REG_EXTENDED;
v->cflags &= ~(REG_ADVF|REG_QUOTE);
break;
case CHR('i'): /* case insensitive */
v->cflags |= REG_ICASE;
break;
case CHR('m'): /* Perloid synonym for n */
case CHR('n'): /* \n affects ^ $ . [^ */
v->cflags |= REG_NEWLINE;
break;
case CHR('p'): /* ~Perl, \n affects . [^ */
v->cflags |= REG_NLSTOP;
v->cflags &= ~REG_NLANCH;
break;
case CHR('q'): /* literal string */
v->cflags |= REG_QUOTE;
v->cflags &= ~REG_ADVANCED;
break;
case CHR('s'): /* single line, \n ordinary */
v->cflags &= ~REG_NEWLINE;
break;
case CHR('t'): /* tight syntax */
v->cflags &= ~REG_EXPANDED;
break;
case CHR('w'): /* weird, \n affects ^ $ only */
v->cflags &= ~REG_NLSTOP;
v->cflags |= REG_NLANCH;
break;
case CHR('x'): /* expanded syntax */
v->cflags |= REG_EXPANDED;
break;
default:
ERR(REG_BADOPT);
return;
}
if (!NEXT1(')')) {
ERR(REG_BADOPT);
return;
}
v->now++;
if (v->cflags&REG_QUOTE)
v->cflags &= ~(REG_EXPANDED|REG_NEWLINE);
}
}
/*
* lexnest - "call a subroutine", interpolating string at the lexical level
*
* Note, this is not a very general facility. There are a number of
* implicit assumptions about what sorts of strings can be subroutines.
*/
static void
lexnest(struct vars *v,
chr *beginp, /* start of interpolation */
chr *endp) /* one past end of interpolation */
{
assert(v->savenow == NULL); /* only one level of nesting */
v->savenow = v->now;
v->savestop = v->stop;
v->now = beginp;
v->stop = endp;
}
/*
* string constants to interpolate as expansions of things like \d
*/
static chr backd[] = { /* \d */
CHR('['), CHR('['), CHR(':'),
CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
CHR(':'), CHR(']'), CHR(']')
};
static chr backD[] = { /* \D */
CHR('['), CHR('^'), CHR('['), CHR(':'),
CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
CHR(':'), CHR(']'), CHR(']')
};
static chr brbackd[] = { /* \d within brackets */
CHR('['), CHR(':'),
CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
CHR(':'), CHR(']')
};
static chr backs[] = { /* \s */
CHR('['), CHR('['), CHR(':'),
CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
CHR(':'), CHR(']'), CHR(']')
};
static chr backS[] = { /* \S */
CHR('['), CHR('^'), CHR('['), CHR(':'),
CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
CHR(':'), CHR(']'), CHR(']')
};
static chr brbacks[] = { /* \s within brackets */
CHR('['), CHR(':'),
CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
CHR(':'), CHR(']')
};
static chr backw[] = { /* \w */
CHR('['), CHR('['), CHR(':'),
CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
CHR(':'), CHR(']'), CHR('_'), CHR(']')
};
static chr backW[] = { /* \W */
CHR('['), CHR('^'), CHR('['), CHR(':'),
CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
CHR(':'), CHR(']'), CHR('_'), CHR(']')
};
static chr brbackw[] = { /* \w within brackets */
CHR('['), CHR(':'),
CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
CHR(':'), CHR(']'), CHR('_')
};
/*
* lexword - interpolate a bracket expression for word characters
* Possibly ought to inquire whether there is a "word" character class.
*/
static void
lexword(struct vars *v)
{
lexnest(v, backw, ENDOF(backw));
}
/*
* next - get next token
*/
static int /* 1 normal, 0 failure */
next(struct vars *v)
{
chr c;
/* errors yield an infinite sequence of failures */
if (ISERR())
return 0; /* the error has set nexttype to EOS */
/* remember flavor of last token */
v->lasttype = v->nexttype;
/* REG_BOSONLY */
if (v->nexttype == EMPTY && (v->cflags&REG_BOSONLY)) {
/* at start of a REG_BOSONLY RE */
RETV(SBEGIN, 0); /* same as \A */
}
/* if we're nested and we've hit end, return to outer level */
if (v->savenow != NULL && ATEOS()) {
v->now = v->savenow;
v->stop = v->savestop;
v->savenow = v->savestop = NULL;
}
/* skip white space etc. if appropriate (not in literal or []) */
if (v->cflags&REG_EXPANDED)
switch (v->lexcon) {
case L_ERE:
case L_BRE:
case L_EBND:
case L_BBND:
skip(v);
break;
}
/* handle EOS, depending on context */
if (ATEOS()) {
switch (v->lexcon) {
case L_ERE:
case L_BRE:
case L_Q:
RET(EOS);
break;
case L_EBND:
case L_BBND:
FAILW(REG_EBRACE);
break;
case L_BRACK:
case L_CEL:
case L_ECL:
case L_CCL:
FAILW(REG_EBRACK);
break;
}
assert(NOTREACHED);
}
/* okay, time to actually get a character */
c = *v->now++;
/* deal with the easy contexts, punt EREs to code below */
switch (v->lexcon) {
case L_BRE: /* punt BREs to separate function */
return brenext(v, c);
break;
case L_ERE: /* see below */
break;
case L_Q: /* literal strings are easy */
RETV(PLAIN, c);
break;
case L_BBND: /* bounds are fairly simple */
case L_EBND:
switch (c) {
case CHR('0'): case CHR('1'): case CHR('2'): case CHR('3'):
case CHR('4'): case CHR('5'): case CHR('6'): case CHR('7'):
case CHR('8'): case CHR('9'):
RETV(DIGIT, (chr)DIGITVAL(c));
break;
case CHR(','):
RET(',');
break;
case CHR('}'): /* ERE bound ends with } */
if (INCON(L_EBND)) {
INTOCON(L_ERE);
if ((v->cflags&REG_ADVF) && NEXT1('?')) {
v->now++;
NOTE(REG_UNONPOSIX);
RETV('}', 0);
}
RETV('}', 1);
} else
FAILW(REG_BADBR);
break;
case CHR('\\'): /* BRE bound ends with \} */
if (INCON(L_BBND) && NEXT1('}')) {
v->now++;
INTOCON(L_BRE);
RET('}');
} else
FAILW(REG_BADBR);
break;
default:
FAILW(REG_BADBR);
break;
}
assert(NOTREACHED);
break;
case L_BRACK: /* brackets are not too hard */
switch (c) {
case CHR(']'):
if (LASTTYPE('['))
RETV(PLAIN, c);
else {
INTOCON((v->cflags&REG_EXTENDED) ?
L_ERE : L_BRE);
RET(']');
}
break;
case CHR('\\'):
NOTE(REG_UBBS);
if (!(v->cflags&REG_ADVF))
RETV(PLAIN, c);
NOTE(REG_UNONPOSIX);
if (ATEOS())
FAILW(REG_EESCAPE);
(DISCARD)lexescape(v);
switch (v->nexttype) { /* not all escapes okay here */
case PLAIN:
return 1;
break;
case CCLASS:
switch (v->nextvalue) {
case 'd':
lexnest(v, brbackd, ENDOF(brbackd));
break;
case 's':
lexnest(v, brbacks, ENDOF(brbacks));
break;
case 'w':
lexnest(v, brbackw, ENDOF(brbackw));
break;
default:
FAILW(REG_EESCAPE);
break;
}
/* lexnest done, back up and try again */
v->nexttype = v->lasttype;
return next(v);
break;
}
/* not one of the acceptable escapes */
FAILW(REG_EESCAPE);
break;
case CHR('-'):
if (LASTTYPE('[') || NEXT1(']'))
RETV(PLAIN, c);
else
RETV(RANGE, c);
break;
case CHR('['):
if (ATEOS())
FAILW(REG_EBRACK);
switch (*v->now++) {
case CHR('.'):
INTOCON(L_CEL);
/* might or might not be locale-specific */
RET(COLLEL);
break;
case CHR('='):
INTOCON(L_ECL);
NOTE(REG_ULOCALE);
RET(ECLASS);
break;
case CHR(':'):
INTOCON(L_CCL);
NOTE(REG_ULOCALE);
RET(CCLASS);
break;
default: /* oops */
v->now--;
RETV(PLAIN, c);
break;
}
assert(NOTREACHED);
break;
default:
RETV(PLAIN, c);
break;
}
assert(NOTREACHED);
break;
case L_CEL: /* collating elements are easy */
if (c == CHR('.') && NEXT1(']')) {
v->now++;
INTOCON(L_BRACK);
RETV(END, '.');
} else
RETV(PLAIN, c);
break;
case L_ECL: /* ditto equivalence classes */
if (c == CHR('=') && NEXT1(']')) {
v->now++;
INTOCON(L_BRACK);
RETV(END, '=');
} else
RETV(PLAIN, c);
break;
case L_CCL: /* ditto character classes */
if (c == CHR(':') && NEXT1(']')) {
v->now++;
INTOCON(L_BRACK);
RETV(END, ':');
} else
RETV(PLAIN, c);
break;
default:
assert(NOTREACHED);
break;
}
/* that got rid of everything except EREs and AREs */
assert(INCON(L_ERE));
/* deal with EREs and AREs, except for backslashes */
switch (c) {
case CHR('|'):
RET('|');
break;
case CHR('*'):
if ((v->cflags&REG_ADVF) && NEXT1('?')) {
v->now++;
NOTE(REG_UNONPOSIX);
RETV('*', 0);
}
RETV('*', 1);
break;
case CHR('+'):
if ((v->cflags&REG_ADVF) && NEXT1('?')) {
v->now++;
NOTE(REG_UNONPOSIX);
RETV('+', 0);
}
RETV('+', 1);
break;
case CHR('?'):
if ((v->cflags&REG_ADVF) && NEXT1('?')) {
v->now++;
NOTE(REG_UNONPOSIX);
RETV('?', 0);
}
RETV('?', 1);
break;
case CHR('{'): /* bounds start or plain character */
if (v->cflags&REG_EXPANDED)
skip(v);
if (ATEOS() || !iscdigit(*v->now)) {
NOTE(REG_UBRACES);
NOTE(REG_UUNSPEC);
RETV(PLAIN, c);
} else {
NOTE(REG_UBOUNDS);
INTOCON(L_EBND);
RET('{');
}
assert(NOTREACHED);
break;
case CHR('('): /* parenthesis, or advanced extension */
if ((v->cflags&REG_ADVF) && NEXT1('?')) {
NOTE(REG_UNONPOSIX);
v->now++;
switch (*v->now++) {
case CHR(':'): /* non-capturing paren */
RETV('(', 0);
break;
case CHR('#'): /* comment */
while (!ATEOS() && *v->now != CHR(')'))
v->now++;
if (!ATEOS())
v->now++;
assert(v->nexttype == v->lasttype);
return next(v);
break;
case CHR('='): /* positive lookahead */
NOTE(REG_ULOOKAHEAD);
RETV(LACON, 1);
break;
case CHR('!'): /* negative lookahead */
NOTE(REG_ULOOKAHEAD);
RETV(LACON, 0);
break;
default:
FAILW(REG_BADRPT);
break;
}
assert(NOTREACHED);
}
if (v->cflags&REG_NOSUB)
RETV('(', 0); /* all parens non-capturing */
else
RETV('(', 1);
break;
case CHR(')'):
if (LASTTYPE('(')) {
NOTE(REG_UUNSPEC);
}
RETV(')', c);
break;
case CHR('['): /* easy except for [[:<:]] and [[:>:]] */
if (HAVE(6) && *(v->now+0) == CHR('[') &&
*(v->now+1) == CHR(':') &&
(*(v->now+2) == CHR('<') ||
*(v->now+2) == CHR('>')) &&
*(v->now+3) == CHR(':') &&
*(v->now+4) == CHR(']') &&
*(v->now+5) == CHR(']')) {
c = *(v->now+2);
v->now += 6;
NOTE(REG_UNONPOSIX);
RET((c == CHR('<')) ? '<' : '>');
}
INTOCON(L_BRACK);
if (NEXT1('^')) {
v->now++;
RETV('[', 0);
}
RETV('[', 1);
break;
case CHR('.'):
RET('.');
break;
case CHR('^'):
RET('^');
break;
case CHR('$'):
RET('$');
break;
case CHR('\\'): /* mostly punt backslashes to code below */
if (ATEOS())
FAILW(REG_EESCAPE);
break;
default: /* ordinary character */
RETV(PLAIN, c);
break;
}
/* ERE/ARE backslash handling; backslash already eaten */
assert(!ATEOS());
if (!(v->cflags&REG_ADVF)) { /* only AREs have non-trivial escapes */
if (iscalnum(*v->now)) {
NOTE(REG_UBSALNUM);
NOTE(REG_UUNSPEC);
}
RETV(PLAIN, *v->now++);
}
(DISCARD)lexescape(v);
if (ISERR())
FAILW(REG_EESCAPE);
if (v->nexttype == CCLASS) { /* fudge at lexical level */
switch (v->nextvalue) {
case 'd': lexnest(v, backd, ENDOF(backd)); break;
case 'D': lexnest(v, backD, ENDOF(backD)); break;
case 's': lexnest(v, backs, ENDOF(backs)); break;
case 'S': lexnest(v, backS, ENDOF(backS)); break;
case 'w': lexnest(v, backw, ENDOF(backw)); break;
case 'W': lexnest(v, backW, ENDOF(backW)); break;
default:
assert(NOTREACHED);
FAILW(REG_ASSERT);
break;
}
/* lexnest done, back up and try again */
v->nexttype = v->lasttype;
return next(v);
}
/* otherwise, lexescape has already done the work */
return !ISERR();
}
/*
* lexescape - parse an ARE backslash escape (backslash already eaten)
* Note slightly nonstandard use of the CCLASS type code.
*/
static int /* not actually used, but convenient for RETV */
lexescape(struct vars *v)
{
chr c;
static chr alert[] = {
CHR('a'), CHR('l'), CHR('e'), CHR('r'), CHR('t')
};
static chr esc[] = {
CHR('E'), CHR('S'), CHR('C')
};
chr *save;
assert(v->cflags&REG_ADVF);
assert(!ATEOS());
c = *v->now++;
if (!iscalnum(c))
RETV(PLAIN, c);
NOTE(REG_UNONPOSIX);
switch (c) {
case CHR('a'):
RETV(PLAIN, chrnamed(v, alert, ENDOF(alert), CHR('\007')));
break;
case CHR('A'):
RETV(SBEGIN, 0);
break;
case CHR('b'):
RETV(PLAIN, CHR('\b'));
break;
case CHR('B'):
RETV(PLAIN, CHR('\\'));
break;
case CHR('c'):
NOTE(REG_UUNPORT);
if (ATEOS())
FAILW(REG_EESCAPE);
RETV(PLAIN, (chr)(*v->now++ & 037));
break;
case CHR('d'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 'd');
break;
case CHR('D'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 'D');
break;
case CHR('e'):
NOTE(REG_UUNPORT);
RETV(PLAIN, chrnamed(v, esc, ENDOF(esc), CHR('\033')));
break;
case CHR('f'):
RETV(PLAIN, CHR('\f'));
break;
case CHR('m'):
RET('<');
break;
case CHR('M'):
RET('>');
break;
case CHR('n'):
RETV(PLAIN, CHR('\n'));
break;
case CHR('r'):
RETV(PLAIN, CHR('\r'));
break;
case CHR('s'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 's');
break;
case CHR('S'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 'S');
break;
case CHR('t'):
RETV(PLAIN, CHR('\t'));
break;
case CHR('u'):
c = lexdigits(v, 16, 4, 4);
if (ISERR())
FAILW(REG_EESCAPE);
RETV(PLAIN, c);
break;
case CHR('U'):
c = lexdigits(v, 16, 8, 8);
if (ISERR())
FAILW(REG_EESCAPE);
RETV(PLAIN, c);
break;
case CHR('v'):
RETV(PLAIN, CHR('\v'));
break;
case CHR('w'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 'w');
break;
case CHR('W'):
NOTE(REG_ULOCALE);
RETV(CCLASS, 'W');
break;
case CHR('x'):
NOTE(REG_UUNPORT);
c = lexdigits(v, 16, 1, 255); /* REs >255 long outside spec */
if (ISERR())
FAILW(REG_EESCAPE);
RETV(PLAIN, c);
break;
case CHR('y'):
NOTE(REG_ULOCALE);
RETV(WBDRY, 0);
break;
case CHR('Y'):
NOTE(REG_ULOCALE);
RETV(NWBDRY, 0);
break;
case CHR('Z'):
RETV(SEND, 0);
break;
case CHR('1'): case CHR('2'): case CHR('3'): case CHR('4'):
case CHR('5'): case CHR('6'): case CHR('7'): case CHR('8'):
case CHR('9'):
save = v->now;
v->now--; /* put first digit back */
c = lexdigits(v, 10, 1, 255); /* REs >255 long outside spec */
if (ISERR())
FAILW(REG_EESCAPE);
/* ugly heuristic (first test is "exactly 1 digit?") */
if (v->now - save == 0 || (int)c <= v->nsubexp) {
NOTE(REG_UBACKREF);
RETV(BACKREF, (chr)c);
}
/* oops, doesn't look like it's a backref after all... */
v->now = save;
/* and fall through into octal number */
case CHR('0'):
NOTE(REG_UUNPORT);
v->now--; /* put first digit back */
c = lexdigits(v, 8, 1, 3);
if (ISERR())
FAILW(REG_EESCAPE);
RETV(PLAIN, c);
break;
default:
assert(iscalpha(c));
FAILW(REG_EESCAPE); /* unknown alphabetic escape */
break;
}
assert(NOTREACHED);
}
/*
* lexdigits - slurp up digits and return chr value
*/
static chr /* chr value; errors signalled via ERR */
lexdigits(struct vars *v,
int base,
int minlen,
int maxlen)
{
uchr n; /* unsigned to avoid overflow misbehavior */
int len;
chr c;
int d;
const uchr ub = (uchr) base;
n = 0;
for (len = 0; len < maxlen && !ATEOS(); len++) {
c = *v->now++;
switch (c) {
case CHR('0'): case CHR('1'): case CHR('2'): case CHR('3'):
case CHR('4'): case CHR('5'): case CHR('6'): case CHR('7'):
case CHR('8'): case CHR('9'):
d = DIGITVAL(c);
break;
case CHR('a'): case CHR('A'): d = 10; break;
case CHR('b'): case CHR('B'): d = 11; break;
case CHR('c'): case CHR('C'): d = 12; break;
case CHR('d'): case CHR('D'): d = 13; break;
case CHR('e'): case CHR('E'): d = 14; break;
case CHR('f'): case CHR('F'): d = 15; break;
default:
v->now--; /* oops, not a digit at all */
d = -1;
break;
}
if (d >= base) { /* not a plausible digit */
v->now--;
d = -1;
}
if (d < 0)
break; /* NOTE BREAK OUT */
n = n*ub + (uchr)d;
}
if (len < minlen)
ERR(REG_EESCAPE);
return (chr)n;
}
/*
* brenext - get next BRE token
*
* This is much like EREs except for all the stupid backslashes and the
* context-dependency of some things.
*/
static int /* 1 normal, 0 failure */
brenext(struct vars *v,
chr pc)
{
chr c = (chr)pc;
switch (c) {
case CHR('*'):
if (LASTTYPE(EMPTY) || LASTTYPE('(') || LASTTYPE('^'))
RETV(PLAIN, c);
RET('*');
break;
case CHR('['):
if (HAVE(6) && *(v->now+0) == CHR('[') &&
*(v->now+1) == CHR(':') &&
(*(v->now+2) == CHR('<') ||
*(v->now+2) == CHR('>')) &&
*(v->now+3) == CHR(':') &&
*(v->now+4) == CHR(']') &&
*(v->now+5) == CHR(']')) {
c = *(v->now+2);
v->now += 6;
NOTE(REG_UNONPOSIX);
RET((c == CHR('<')) ? '<' : '>');
}
INTOCON(L_BRACK);
if (NEXT1('^')) {
v->now++;
RETV('[', 0);
}
RETV('[', 1);
break;
case CHR('.'):
RET('.');
break;
case CHR('^'):
if (LASTTYPE(EMPTY))
RET('^');
if (LASTTYPE('(')) {
NOTE(REG_UUNSPEC);
RET('^');
}
RETV(PLAIN, c);
break;
case CHR('$'):
if (v->cflags&REG_EXPANDED)
skip(v);
if (ATEOS())
RET('$');
if (NEXT2('\\', ')')) {
NOTE(REG_UUNSPEC);
RET('$');
}
RETV(PLAIN, c);
break;
case CHR('\\'):
break; /* see below */
default:
RETV(PLAIN, c);
break;
}
assert(c == CHR('\\'));
if (ATEOS())
FAILW(REG_EESCAPE);
c = *v->now++;
switch (c) {
case CHR('{'):
INTOCON(L_BBND);
NOTE(REG_UBOUNDS);
RET('{');
break;
case CHR('('):
RETV('(', 1);
break;
case CHR(')'):
RETV(')', c);
break;
case CHR('<'):
NOTE(REG_UNONPOSIX);
RET('<');
break;
case CHR('>'):
NOTE(REG_UNONPOSIX);
RET('>');
break;
case CHR('1'): case CHR('2'): case CHR('3'): case CHR('4'):
case CHR('5'): case CHR('6'): case CHR('7'): case CHR('8'):
case CHR('9'):
NOTE(REG_UBACKREF);
RETV(BACKREF, (chr)DIGITVAL(c));
break;
default:
if (iscalnum(c)) {
NOTE(REG_UBSALNUM);
NOTE(REG_UUNSPEC);
}
RETV(PLAIN, c);
break;
}
assert(NOTREACHED);
}
/*
* skip - skip white space and comments in expanded form
*/
static void
skip(struct vars *v)
{
chr *start = v->now;
assert(v->cflags&REG_EXPANDED);
for (;;) {
while (!ATEOS() && iscspace(*v->now))
v->now++;
if (ATEOS() || *v->now != CHR('#'))
break; /* NOTE BREAK OUT */
assert(NEXT1('#'));
while (!ATEOS() && *v->now != CHR('\n'))
v->now++;
/* leave the newline to be picked up by the iscspace loop */
}
if (v->now != start)
NOTE(REG_UNONPOSIX);
}
/*
* newline - return the chr for a newline
*
* This helps confine use of CHR to this source file.
*/
static chr
newline(void)
{
return CHR('\n');
}
/*
* chrnamed - return the chr known by a given (chr string) name
*
* The code is a bit clumsy, but this routine gets only such specialized
* use that it hardly matters.
*/
static chr
chrnamed(struct vars *v,
chr *startp, /* start of name */
chr *endp, /* just past end of name */
chr lastresort) /* what to return if name lookup fails */
{
celt c;
int errsave;
int e;
struct cvec *cv;
errsave = v->err;
v->err = 0;
c = element(v, startp, endp);
e = v->err;
v->err = errsave;
if (e != 0)
return (chr)lastresort;
cv = range(v, c, c, 0);
if (cv->nchrs == 0)
return (chr)lastresort;
return cv->chrs[0];
}
src/backend/regex/regc_locale.c 0 → 100644
View file @ 7bcc6d98
/*
* regc_locale.c --
*
* This file contains locale-specific regexp routines.
* This file is #included by regcomp.c.
*
* Copyright (c) 1998 by Scriptics Corporation.
*
* This software is copyrighted by the Regents of the University of
* California, Sun Microsystems, Inc., Scriptics Corporation, ActiveState
* Corporation and other parties. The following terms apply to all files
* associated with the software unless explicitly disclaimed in
* individual files.
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice is included verbatim in any distributions. No written agreement,
* license, or royalty fee is required for any of the authorized uses.
* Modifications to this software may be copyrighted by their authors
* and need not follow the licensing terms described here, provided that
* the new terms are clearly indicated on the first page of each file where
* they apply.
*
* IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
* FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
* DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. THIS SOFTWARE
* IS PROVIDED ON AN "AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE
* NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR
* MODIFICATIONS.
*
* GOVERNMENT USE: If you are acquiring this software on behalf of the
* U.S. government, the Government shall have only "Restricted Rights"
* in the software and related documentation as defined in the Federal
* Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you
* are acquiring the software on behalf of the Department of Defense, the
* software shall be classified as "Commercial Computer Software" and the
* Government shall have only "Restricted Rights" as defined in Clause
* 252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
* authors grant the U.S. Government and others acting in its behalf
* permission to use and distribute the software in accordance with the
* terms specified in this license.
*
* $Header: /cvsroot/pgsql/src/backend/regex/regc_locale.c,v 1.1 2003/02/05 17:41:32 tgl Exp $
*/
/* ASCII character-name table */
static struct cname {
char *name;
char code;
} cnames[] = {
{"NUL", '\0'},
{"SOH", '\001'},
{"STX", '\002'},
{"ETX", '\003'},
{"EOT", '\004'},
{"ENQ", '\005'},
{"ACK", '\006'},
{"BEL", '\007'},
{"alert", '\007'},
{"BS", '\010'},
{"backspace", '\b'},
{"HT", '\011'},
{"tab", '\t'},
{"LF", '\012'},
{"newline", '\n'},
{"VT", '\013'},
{"vertical-tab", '\v'},
{"FF", '\014'},
{"form-feed", '\f'},
{"CR", '\015'},
{"carriage-return", '\r'},
{"SO", '\016'},
{"SI", '\017'},
{"DLE", '\020'},
{"DC1", '\021'},
{"DC2", '\022'},
{"DC3", '\023'},
{"DC4", '\024'},
{"NAK", '\025'},
{"SYN", '\026'},
{"ETB", '\027'},
{"CAN", '\030'},
{"EM", '\031'},
{"SUB", '\032'},
{"ESC", '\033'},
{"IS4", '\034'},
{"FS", '\034'},
{"IS3", '\035'},
{"GS", '\035'},
{"IS2", '\036'},
{"RS", '\036'},
{"IS1", '\037'},
{"US", '\037'},
{"space", ' '},
{"exclamation-mark",'!'},
{"quotation-mark", '"'},
{"number-sign", '#'},
{"dollar-sign", '$'},
{"percent-sign", '%'},
{"ampersand", '&'},
{"apostrophe", '\''},
{"left-parenthesis",'('},
{"right-parenthesis", ')'},
{"asterisk", '*'},
{"plus-sign", '+'},
{"comma", ','},
{"hyphen", '-'},
{"hyphen-minus", '-'},
{"period", '.'},
{"full-stop", '.'},
{"slash", '/'},
{"solidus", '/'},
{"zero", '0'},
{"one", '1'},
{"two", '2'},
{"three", '3'},
{"four", '4'},
{"five", '5'},
{"six", '6'},
{"seven", '7'},
{"eight", '8'},
{"nine", '9'},
{"colon", ':'},
{"semicolon", ';'},
{"less-than-sign", '<'},
{"equals-sign", '='},
{"greater-than-sign", '>'},
{"question-mark", '?'},
{"commercial-at", '@'},
{"left-square-bracket", '['},
{"backslash", '\\'},
{"reverse-solidus", '\\'},
{"right-square-bracket", ']'},
{"circumflex", '^'},
{"circumflex-accent", '^'},
{"underscore", '_'},
{"low-line", '_'},
{"grave-accent", '`'},
{"left-brace", '{'},
{"left-curly-bracket", '{'},
{"vertical-line", '|'},
{"right-brace", '}'},
{"right-curly-bracket", '}'},
{"tilde", '~'},
{"DEL", '\177'},
{NULL, 0}
};
/*
* some ctype functions with non-ascii-char guard
*/
static int
pg_isdigit(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isdigit((unsigned char) c));
}
static int
pg_isalpha(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isalpha((unsigned char) c));
}
static int
pg_isalnum(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isalnum((unsigned char) c));
}
static int
pg_isupper(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isupper((unsigned char) c));
}
static int
pg_islower(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && islower((unsigned char) c));
}
static int
pg_isgraph(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isgraph((unsigned char) c));
}
static int
pg_ispunct(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && ispunct((unsigned char) c));
}
static int
pg_isspace(pg_wchar c)
{
return (c >= 0 && c <= UCHAR_MAX && isspace((unsigned char) c));
}
static pg_wchar
pg_toupper(pg_wchar c)
{
if (c >= 0 && c <= UCHAR_MAX)
return toupper((unsigned char) c);
return c;
}
static pg_wchar
pg_tolower(pg_wchar c)
{
if (c >= 0 && c <= UCHAR_MAX)
return tolower((unsigned char) c);
return c;
}
/*
* nmcces - how many distinct MCCEs are there?
*/
static int
nmcces(struct vars *v)
{
/*
* No multi-character collating elements defined at the moment.
*/
return 0;
}
/*
* nleaders - how many chrs can be first chrs of MCCEs?
*/
static int
nleaders(struct vars *v)
{
return 0;
}
/*
* allmcces - return a cvec with all the MCCEs of the locale
*/
static struct cvec *
allmcces(struct vars *v, /* context */
struct cvec *cv) /* this is supposed to have enough room */
{
return clearcvec(cv);
}
/*
* element - map collating-element name to celt
*/
static celt
element(struct vars *v, /* context */
chr *startp, /* points to start of name */
chr *endp) /* points just past end of name */
{
struct cname *cn;
size_t len;
/* generic: one-chr names stand for themselves */
assert(startp < endp);
len = endp - startp;
if (len == 1) {
return *startp;
}
NOTE(REG_ULOCALE);
/* search table */
for (cn=cnames; cn->name!=NULL; cn++) {
if (strlen(cn->name)==len &&
pg_char_and_wchar_strncmp(cn->name, startp, len)==0) {
break; /* NOTE BREAK OUT */
}
}
if (cn->name != NULL) {
return CHR(cn->code);
}
/* couldn't find it */
ERR(REG_ECOLLATE);
return 0;
}
/*
* range - supply cvec for a range, including legality check
*/
static struct cvec *
range(struct vars *v, /* context */
celt a, /* range start */
celt b, /* range end, might equal a */
int cases) /* case-independent? */
{
int nchrs;
struct cvec *cv;
celt c, lc, uc;
if (a != b && !before(a, b)) {
ERR(REG_ERANGE);
return NULL;
}
if (!cases) { /* easy version */
cv = getcvec(v, 0, 1, 0);
NOERRN();
addrange(cv, a, b);
return cv;
}
/*
* When case-independent, it's hard to decide when cvec ranges are
* usable, so for now at least, we won't try. We allocate enough
* space for two case variants plus a little extra for the two
* title case variants.
*/
nchrs = (b - a + 1)*2 + 4;
cv = getcvec(v, nchrs, 0, 0);
NOERRN();
for (c=a; c<=b; c++) {
addchr(cv, c);
lc = pg_tolower((chr)c);
if (c != lc) {
addchr(cv, lc);
}
uc = pg_toupper((chr)c);
if (c != uc) {
addchr(cv, uc);
}
}
return cv;
}
/*
* before - is celt x before celt y, for purposes of range legality?
*/
static int /* predicate */
before(celt x, celt y)
{
/* trivial because no MCCEs */
if (x < y) {
return 1;
}
return 0;
}
/*
* eclass - supply cvec for an equivalence class
* Must include case counterparts on request.
*/
static struct cvec *
eclass(struct vars *v, /* context */
celt c, /* Collating element representing
* the equivalence class. */
int cases) /* all cases? */
{
struct cvec *cv;
/* crude fake equivalence class for testing */
if ((v->cflags&REG_FAKE) && c == 'x') {
cv = getcvec(v, 4, 0, 0);
addchr(cv, (chr)'x');
addchr(cv, (chr)'y');
if (cases) {
addchr(cv, (chr)'X');
addchr(cv, (chr)'Y');
}
return cv;
}
/* otherwise, none */
if (cases) {
return allcases(v, c);
}
cv = getcvec(v, 1, 0, 0);
assert(cv != NULL);
addchr(cv, (chr)c);
return cv;
}
/*
* cclass - supply cvec for a character class
*
* Must include case counterparts on request.
*/
static struct cvec *
cclass(struct vars *v, /* context */
chr *startp, /* where the name starts */
chr *endp, /* just past the end of the name */
int cases) /* case-independent? */
{
size_t len;
struct cvec *cv = NULL;
char **namePtr;
int i, index;
/*
* The following arrays define the valid character class names.
*/
static char *classNames[] = {
"alnum", "alpha", "ascii", "blank", "cntrl", "digit", "graph",
"lower", "print", "punct", "space", "upper", "xdigit", NULL
};
enum classes {
CC_ALNUM, CC_ALPHA, CC_ASCII, CC_BLANK, CC_CNTRL, CC_DIGIT, CC_GRAPH,
CC_LOWER, CC_PRINT, CC_PUNCT, CC_SPACE, CC_UPPER, CC_XDIGIT
};
/*
* Map the name to the corresponding enumerated value.
*/
len = endp - startp;
index = -1;
for (namePtr=classNames,i=0 ; *namePtr!=NULL ; namePtr++,i++) {
if (strlen(*namePtr) == len &&
pg_char_and_wchar_strncmp(*namePtr, startp, len) == 0) {
index = i;
break;
}
}
if (index == -1) {
ERR(REG_ECTYPE);
return NULL;
}
/*
* Remap lower and upper to alpha if the match is case insensitive.
*/
if (cases &&
((enum classes) index == CC_LOWER ||
(enum classes) index == CC_UPPER))
index = (int) CC_ALPHA;
/*
* Now compute the character class contents.
*
* For the moment, assume that only char codes < 256 can be in these
* classes.
*/
switch((enum classes) index) {
case CC_PRINT:
case CC_ALNUM:
cv = getcvec(v, UCHAR_MAX, 1, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_isalpha((chr) i))
addchr(cv, (chr) i);
}
addrange(cv, (chr) '0', (chr) '9');
}
break;
case CC_ALPHA:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_isalpha((chr) i))
addchr(cv, (chr) i);
}
}
break;
case CC_ASCII:
cv = getcvec(v, 0, 1, 0);
if (cv) {
addrange(cv, 0, 0x7f);
}
break;
case CC_BLANK:
cv = getcvec(v, 2, 0, 0);
addchr(cv, '\t');
addchr(cv, ' ');
break;
case CC_CNTRL:
cv = getcvec(v, 0, 2, 0);
addrange(cv, 0x0, 0x1f);
addrange(cv, 0x7f, 0x9f);
break;
case CC_DIGIT:
cv = getcvec(v, 0, 1, 0);
if (cv) {
addrange(cv, (chr) '0', (chr) '9');
}
break;
case CC_PUNCT:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_ispunct((chr) i))
addchr(cv, (chr) i);
}
}
break;
case CC_XDIGIT:
cv = getcvec(v, 0, 3, 0);
if (cv) {
addrange(cv, '0', '9');
addrange(cv, 'a', 'f');
addrange(cv, 'A', 'F');
}
break;
case CC_SPACE:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_isspace((chr) i))
addchr(cv, (chr) i);
}
}
break;
case CC_LOWER:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_islower((chr) i))
addchr(cv, (chr) i);
}
}
break;
case CC_UPPER:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_isupper((chr) i))
addchr(cv, (chr) i);
}
}
break;
case CC_GRAPH:
cv = getcvec(v, UCHAR_MAX, 0, 0);
if (cv) {
for (i=0 ; i<= UCHAR_MAX ; i++) {
if (pg_isgraph((chr) i))
addchr(cv, (chr) i);
}
}
break;
}
if (cv == NULL) {
ERR(REG_ESPACE);
}
return cv;
}
/*
* allcases - supply cvec for all case counterparts of a chr (including itself)
*
* This is a shortcut, preferably an efficient one, for simple characters;
* messy cases are done via range().
*/
static struct cvec *
allcases(struct vars *v, /* context */
chr pc) /* character to get case equivs of */
{
struct cvec *cv;
chr c = (chr)pc;
chr lc, uc;
lc = pg_tolower((chr)c);
uc = pg_toupper((chr)c);
cv = getcvec(v, 2, 0, 0);
addchr(cv, lc);
if (lc != uc) {
addchr(cv, uc);
}
return cv;
}
/*
* cmp - chr-substring compare
*
* Backrefs need this. It should preferably be efficient.
* Note that it does not need to report anything except equal/unequal.
* Note also that the length is exact, and the comparison should not
* stop at embedded NULs!
*/
static int /* 0 for equal, nonzero for unequal */
cmp(const chr *x, const chr *y, /* strings to compare */
size_t len) /* exact length of comparison */
{
return memcmp(VS(x), VS(y), len*sizeof(chr));
}
/*
* casecmp - case-independent chr-substring compare
*
* REG_ICASE backrefs need this. It should preferably be efficient.
* Note that it does not need to report anything except equal/unequal.
* Note also that the length is exact, and the comparison should not
* stop at embedded NULs!
*/
static int /* 0 for equal, nonzero for unequal */
casecmp(const chr *x, const chr *y, /* strings to compare */
size_t len) /* exact length of comparison */
{
for (; len > 0; len--, x++, y++) {
if ((*x!=*y) && (pg_tolower(*x) != pg_tolower(*y))) {
return 1;
}
}
return 0;
}
src/backend/regex/regc_nfa.c 0 → 100644
View file @ 7bcc6d98
/*
* NFA utilities.
* This file is #included by regcomp.c.
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Header: /cvsroot/pgsql/src/backend/regex/regc_nfa.c,v 1.1 2003/02/05 17:41:32 tgl Exp $
*
*
* One or two things that technically ought to be in here
* are actually in color.c, thanks to some incestuous relationships in
* the color chains.
*/
#define NISERR() VISERR(nfa->v)
#define NERR(e) VERR(nfa->v, (e))
/*
* newnfa - set up an NFA
*/
static struct nfa * /* the NFA, or NULL */
newnfa(struct vars *v,
struct colormap *cm,
struct nfa *parent) /* NULL if primary NFA */
{
struct nfa *nfa;
nfa = (struct nfa *)MALLOC(sizeof(struct nfa));
if (nfa == NULL)
return NULL;
nfa->states = NULL;
nfa->slast = NULL;
nfa->free = NULL;
nfa->nstates = 0;
nfa->cm = cm;
nfa->v = v;
nfa->bos[0] = nfa->bos[1] = COLORLESS;
nfa->eos[0] = nfa->eos[1] = COLORLESS;
nfa->post = newfstate(nfa, '@'); /* number 0 */
nfa->pre = newfstate(nfa, '>'); /* number 1 */
nfa->parent = parent;
nfa->init = newstate(nfa); /* may become invalid later */
nfa->final = newstate(nfa);
if (ISERR()) {
freenfa(nfa);
return NULL;
}
rainbow(nfa, nfa->cm, PLAIN, COLORLESS, nfa->pre, nfa->init);
newarc(nfa, '^', 1, nfa->pre, nfa->init);
newarc(nfa, '^', 0, nfa->pre, nfa->init);
rainbow(nfa, nfa->cm, PLAIN, COLORLESS, nfa->final, nfa->post);
newarc(nfa, '$', 1, nfa->final, nfa->post);
newarc(nfa, '$', 0, nfa->final, nfa->post);
if (ISERR()) {
freenfa(nfa);
return NULL;
}
return nfa;
}
/*
* freenfa - free an entire NFA
*/
static void
freenfa(struct nfa *nfa)
{
struct state *s;
while ((s = nfa->states) != NULL) {
s->nins = s->nouts = 0; /* don't worry about arcs */
freestate(nfa, s);
}
while ((s = nfa->free) != NULL) {
nfa->free = s->next;
destroystate(nfa, s);
}
nfa->slast = NULL;
nfa->nstates = -1;
nfa->pre = NULL;
nfa->post = NULL;
FREE(nfa);
}
/*
* newstate - allocate an NFA state, with zero flag value
*/
static struct state * /* NULL on error */
newstate(struct nfa *nfa)
{
struct state *s;
if (nfa->free != NULL) {
s = nfa->free;
nfa->free = s->next;
} else {
s = (struct state *)MALLOC(sizeof(struct state));
if (s == NULL) {
NERR(REG_ESPACE);
return NULL;
}
s->oas.next = NULL;
s->free = NULL;
s->noas = 0;
}
assert(nfa->nstates >= 0);
s->no = nfa->nstates++;
s->flag = 0;
if (nfa->states == NULL)
nfa->states = s;
s->nins = 0;
s->ins = NULL;
s->nouts = 0;
s->outs = NULL;
s->tmp = NULL;
s->next = NULL;
if (nfa->slast != NULL) {
assert(nfa->slast->next == NULL);
nfa->slast->next = s;
}
s->prev = nfa->slast;
nfa->slast = s;
return s;
}
/*
* newfstate - allocate an NFA state with a specified flag value
*/
static struct state * /* NULL on error */
newfstate(struct nfa *nfa, int flag)
{
struct state *s;
s = newstate(nfa);
if (s != NULL)
s->flag = (char)flag;
return s;
}
/*
* dropstate - delete a state's inarcs and outarcs and free it
*/
static void
dropstate(struct nfa *nfa,
struct state *s)
{
struct arc *a;
while ((a = s->ins) != NULL)
freearc(nfa, a);
while ((a = s->outs) != NULL)
freearc(nfa, a);
freestate(nfa, s);
}
/*
* freestate - free a state, which has no in-arcs or out-arcs
*/
static void
freestate(struct nfa *nfa,
struct state *s)
{
assert(s != NULL);
assert(s->nins == 0 && s->nouts == 0);
s->no = FREESTATE;
s->flag = 0;
if (s->next != NULL)
s->next->prev = s->prev;
else {
assert(s == nfa->slast);
nfa->slast = s->prev;
}
if (s->prev != NULL)
s->prev->next = s->next;
else {
assert(s == nfa->states);
nfa->states = s->next;
}
s->prev = NULL;
s->next = nfa->free; /* don't delete it, put it on the free list */
nfa->free = s;
}
/*
* destroystate - really get rid of an already-freed state
*/
static void
destroystate(struct nfa *nfa,
struct state *s)
{
struct arcbatch *ab;
struct arcbatch *abnext;
assert(s->no == FREESTATE);
for (ab = s->oas.next; ab != NULL; ab = abnext) {
abnext = ab->next;
FREE(ab);
}
s->ins = NULL;
s->outs = NULL;
s->next = NULL;
FREE(s);
}
/*
* newarc - set up a new arc within an NFA
*/
static void
newarc(struct nfa *nfa,
int t,
pcolor co,
struct state *from,
struct state *to)
{
struct arc *a;
assert(from != NULL && to != NULL);
/* check for duplicates */
for (a = from->outs; a != NULL; a = a->outchain)
if (a->to == to && a->co == co && a->type == t)
return;
a = allocarc(nfa, from);
if (NISERR())
return;
assert(a != NULL);
a->type = t;
a->co = (color)co;
a->to = to;
a->from = from;
/*
* Put the new arc on the beginning, not the end, of the chains.
* Not only is this easier, it has the very useful side effect that
* deleting the most-recently-added arc is the cheapest case rather
* than the most expensive one.
*/
a->inchain = to->ins;
to->ins = a;
a->outchain = from->outs;
from->outs = a;
from->nouts++;
to->nins++;
if (COLORED(a) && nfa->parent == NULL)
colorchain(nfa->cm, a);
return;
}
/*
* allocarc - allocate a new out-arc within a state
*/
static struct arc * /* NULL for failure */
allocarc(struct nfa *nfa,
struct state *s)
{
struct arc *a;
struct arcbatch *new;
int i;
/* shortcut */
if (s->free == NULL && s->noas < ABSIZE) {
a = &s->oas.a[s->noas];
s->noas++;
return a;
}
/* if none at hand, get more */
if (s->free == NULL) {
new = (struct arcbatch *)MALLOC(sizeof(struct arcbatch));
if (new == NULL) {
NERR(REG_ESPACE);
return NULL;
}
new->next = s->oas.next;
s->oas.next = new;
for (i = 0; i < ABSIZE; i++) {
new->a[i].type = 0;
new->a[i].freechain = &new->a[i+1];
}
new->a[ABSIZE-1].freechain = NULL;
s->free = &new->a[0];
}
assert(s->free != NULL);
a = s->free;
s->free = a->freechain;
return a;
}
/*
* freearc - free an arc
*/
static void
freearc(struct nfa *nfa,
struct arc *victim)
{
struct state *from = victim->from;
struct state *to = victim->to;
struct arc *a;
assert(victim->type != 0);
/* take it off color chain if necessary */
if (COLORED(victim) && nfa->parent == NULL)
uncolorchain(nfa->cm, victim);
/* take it off source's out-chain */
assert(from != NULL);
assert(from->outs != NULL);
a = from->outs;
if (a == victim) /* simple case: first in chain */
from->outs = victim->outchain;
else {
for (; a != NULL && a->outchain != victim; a = a->outchain)
continue;
assert(a != NULL);
a->outchain = victim->outchain;
}
from->nouts--;
/* take it off target's in-chain */
assert(to != NULL);
assert(to->ins != NULL);
a = to->ins;
if (a == victim) /* simple case: first in chain */
to->ins = victim->inchain;
else {
for (; a != NULL && a->inchain != victim; a = a->inchain)
continue;
assert(a != NULL);
a->inchain = victim->inchain;
}
to->nins--;
/* clean up and place on free list */
victim->type = 0;
victim->from = NULL; /* precautions... */
victim->to = NULL;
victim->inchain = NULL;
victim->outchain = NULL;
victim->freechain = from->free;
from->free = victim;
}
/*
* findarc - find arc, if any, from given source with given type and color
* If there is more than one such arc, the result is random.
*/
static struct arc *
findarc(struct state *s,
int type,
pcolor co)
{
struct arc *a;
for (a = s->outs; a != NULL; a = a->outchain)
if (a->type == type && a->co == co)
return a;
return NULL;
}
/*
* cparc - allocate a new arc within an NFA, copying details from old one
*/
static void
cparc(struct nfa *nfa,
struct arc *oa,
struct state *from,
struct state *to)
{
newarc(nfa, oa->type, oa->co, from, to);
}
/*
* moveins - move all in arcs of a state to another state
*
* You might think this could be done better by just updating the
* existing arcs, and you would be right if it weren't for the desire
* for duplicate suppression, which makes it easier to just make new
* ones to exploit the suppression built into newarc.
*/
static void
moveins(struct nfa *nfa,
struct state *old,
struct state *new)
{
struct arc *a;
assert(old != new);
while ((a = old->ins) != NULL) {
cparc(nfa, a, a->from, new);
freearc(nfa, a);
}
assert(old->nins == 0);
assert(old->ins == NULL);
}
/*
* copyins - copy all in arcs of a state to another state
*/
static void
copyins(struct nfa *nfa,
struct state *old,
struct state *new)
{
struct arc *a;
assert(old != new);
for (a = old->ins; a != NULL; a = a->inchain)
cparc(nfa, a, a->from, new);
}
/*
* moveouts - move all out arcs of a state to another state
*/
static void
moveouts(struct nfa *nfa,
struct state *old,
struct state *new)
{
struct arc *a;
assert(old != new);
while ((a = old->outs) != NULL) {
cparc(nfa, a, new, a->to);
freearc(nfa, a);
}
}
/*
* copyouts - copy all out arcs of a state to another state
*/
static void
copyouts(struct nfa *nfa,
struct state *old,
struct state *new)
{
struct arc *a;
assert(old != new);
for (a = old->outs; a != NULL; a = a->outchain)
cparc(nfa, a, new, a->to);
}
/*
* cloneouts - copy out arcs of a state to another state pair, modifying type
*/
static void
cloneouts(struct nfa *nfa,
struct state *old,
struct state *from,
struct state *to,
int type)
{
struct arc *a;
assert(old != from);
for (a = old->outs; a != NULL; a = a->outchain)
newarc(nfa, type, a->co, from, to);
}
/*
* delsub - delete a sub-NFA, updating subre pointers if necessary
*
* This uses a recursive traversal of the sub-NFA, marking already-seen
* states using their tmp pointer.
*/
static void
delsub(struct nfa *nfa,
struct state *lp, /* the sub-NFA goes from here... */
struct state *rp) /* ...to here, *not* inclusive */
{
assert(lp != rp);
rp->tmp = rp; /* mark end */
deltraverse(nfa, lp, lp);
assert(lp->nouts == 0 && rp->nins == 0); /* did the job */
assert(lp->no != FREESTATE && rp->no != FREESTATE); /* no more */
rp->tmp = NULL; /* unmark end */
lp->tmp = NULL; /* and begin, marked by deltraverse */
}
/*
* deltraverse - the recursive heart of delsub
* This routine's basic job is to destroy all out-arcs of the state.
*/
static void
deltraverse(struct nfa *nfa,
struct state *leftend,
struct state *s)
{
struct arc *a;
struct state *to;
if (s->nouts == 0)
return; /* nothing to do */
if (s->tmp != NULL)
return; /* already in progress */
s->tmp = s; /* mark as in progress */
while ((a = s->outs) != NULL) {
to = a->to;
deltraverse(nfa, leftend, to);
assert(to->nouts == 0 || to->tmp != NULL);
freearc(nfa, a);
if (to->nins == 0 && to->tmp == NULL) {
assert(to->nouts == 0);
freestate(nfa, to);
}
}
assert(s->no != FREESTATE); /* we're still here */
assert(s == leftend || s->nins != 0); /* and still reachable */
assert(s->nouts == 0); /* but have no outarcs */
s->tmp = NULL; /* we're done here */
}
/*
* dupnfa - duplicate sub-NFA
*
* Another recursive traversal, this time using tmp to point to duplicates
* as well as mark already-seen states. (You knew there was a reason why
* it's a state pointer, didn't you? :-))
*/
static void
dupnfa(struct nfa *nfa,
struct state *start, /* duplicate of subNFA starting here */
struct state *stop, /* and stopping here */
struct state *from, /* stringing duplicate from here */
struct state *to) /* to here */
{
if (start == stop) {
newarc(nfa, EMPTY, 0, from, to);
return;
}
stop->tmp = to;
duptraverse(nfa, start, from);
/* done, except for clearing out the tmp pointers */
stop->tmp = NULL;
cleartraverse(nfa, start);
}
/*
* duptraverse - recursive heart of dupnfa
*/
static void
duptraverse(struct nfa *nfa,
struct state *s,
struct state *stmp) /* s's duplicate, or NULL */
{
struct arc *a;
if (s->tmp != NULL)
return; /* already done */
s->tmp = (stmp == NULL) ? newstate(nfa) : stmp;
if (s->tmp == NULL) {
assert(NISERR());
return;
}
for (a = s->outs; a != NULL && !NISERR(); a = a->outchain) {
duptraverse(nfa, a->to, (struct state *)NULL);
assert(a->to->tmp != NULL);
cparc(nfa, a, s->tmp, a->to->tmp);
}
}
/*
* cleartraverse - recursive cleanup for algorithms that leave tmp ptrs set
*/
static void
cleartraverse(struct nfa *nfa,
struct state *s)
{
struct arc *a;
if (s->tmp == NULL)
return;
s->tmp = NULL;
for (a = s->outs; a != NULL; a = a->outchain)
cleartraverse(nfa, a->to);
}
/*
* specialcolors - fill in special colors for an NFA
*/
static void
specialcolors(struct nfa *nfa)
{
/* false colors for BOS, BOL, EOS, EOL */
if (nfa->parent == NULL) {
nfa->bos[0] = pseudocolor(nfa->cm);
nfa->bos[1] = pseudocolor(nfa->cm);
nfa->eos[0] = pseudocolor(nfa->cm);
nfa->eos[1] = pseudocolor(nfa->cm);
} else {
assert(nfa->parent->bos[0] != COLORLESS);
nfa->bos[0] = nfa->parent->bos[0];
assert(nfa->parent->bos[1] != COLORLESS);
nfa->bos[1] = nfa->parent->bos[1];
assert(nfa->parent->eos[0] != COLORLESS);
nfa->eos[0] = nfa->parent->eos[0];
assert(nfa->parent->eos[1] != COLORLESS);
nfa->eos[1] = nfa->parent->eos[1];
}
}
/*
* optimize - optimize an NFA
*/
static long /* re_info bits */
optimize(struct nfa *nfa,
FILE *f) /* for debug output; NULL none */
{
#ifdef REG_DEBUG
int verbose = (f != NULL) ? 1 : 0;
if (verbose)
fprintf(f, "\ninitial cleanup:\n");
#endif
cleanup(nfa); /* may simplify situation */
#ifdef REG_DEBUG
if (verbose)
dumpnfa(nfa, f);
if (verbose)
fprintf(f, "\nempties:\n");
#endif
fixempties(nfa, f); /* get rid of EMPTY arcs */
#ifdef REG_DEBUG
if (verbose)
fprintf(f, "\nconstraints:\n");
#endif
pullback(nfa, f); /* pull back constraints backward */
pushfwd(nfa, f); /* push fwd constraints forward */
#ifdef REG_DEBUG
if (verbose)
fprintf(f, "\nfinal cleanup:\n");
#endif
cleanup(nfa); /* final tidying */
return analyze(nfa); /* and analysis */
}
/*
* pullback - pull back constraints backward to (with luck) eliminate them
*/
static void
pullback(struct nfa *nfa,
FILE *f) /* for debug output; NULL none */
{
struct state *s;
struct state *nexts;
struct arc *a;
struct arc *nexta;
int progress;
/* find and pull until there are no more */
do {
progress = 0;
for (s = nfa->states; s != NULL && !NISERR(); s = nexts) {
nexts = s->next;
for (a = s->outs; a != NULL && !NISERR(); a = nexta) {
nexta = a->outchain;
if (a->type == '^' || a->type == BEHIND)
if (pull(nfa, a))
progress = 1;
assert(nexta == NULL || s->no != FREESTATE);
}
}
if (progress && f != NULL)
dumpnfa(nfa, f);
} while (progress && !NISERR());
if (NISERR())
return;
for (a = nfa->pre->outs; a != NULL; a = nexta) {
nexta = a->outchain;
if (a->type == '^') {
assert(a->co == 0 || a->co == 1);
newarc(nfa, PLAIN, nfa->bos[a->co], a->from, a->to);
freearc(nfa, a);
}
}
}
/*
* pull - pull a back constraint backward past its source state
* A significant property of this function is that it deletes at most
* one state -- the constraint's from state -- and only if the constraint
* was that state's last outarc.
*/
static int /* 0 couldn't, 1 could */
pull(struct nfa *nfa,
struct arc *con)
{
struct state *from = con->from;
struct state *to = con->to;
struct arc *a;
struct arc *nexta;
struct state *s;
if (from == to) { /* circular constraint is pointless */
freearc(nfa, con);
return 1;
}
if (from->flag) /* can't pull back beyond start */
return 0;
if (from->nins == 0) { /* unreachable */
freearc(nfa, con);
return 1;
}
/* first, clone from state if necessary to avoid other outarcs */
if (from->nouts > 1) {
s = newstate(nfa);
if (NISERR())
return 0;
assert(to != from); /* con is not an inarc */
copyins(nfa, from, s); /* duplicate inarcs */
cparc(nfa, con, s, to); /* move constraint arc */
freearc(nfa, con);
from = s;
con = from->outs;
}
assert(from->nouts == 1);
/* propagate the constraint into the from state's inarcs */
for (a = from->ins; a != NULL; a = nexta) {
nexta = a->inchain;
switch (combine(con, a)) {
case INCOMPATIBLE: /* destroy the arc */
freearc(nfa, a);
break;
case SATISFIED: /* no action needed */
break;
case COMPATIBLE: /* swap the two arcs, more or less */
s = newstate(nfa);
if (NISERR())
return 0;
cparc(nfa, a, s, to); /* anticipate move */
cparc(nfa, con, a->from, s);
if (NISERR())
return 0;
freearc(nfa, a);
break;
default:
assert(NOTREACHED);
break;
}
}
/* remaining inarcs, if any, incorporate the constraint */
moveins(nfa, from, to);
dropstate(nfa, from); /* will free the constraint */
return 1;
}
/*
* pushfwd - push forward constraints forward to (with luck) eliminate them
*/
static void
pushfwd(struct nfa *nfa,
FILE *f) /* for debug output; NULL none */
{
struct state *s;
struct state *nexts;
struct arc *a;
struct arc *nexta;
int progress;
/* find and push until there are no more */
do {
progress = 0;
for (s = nfa->states; s != NULL && !NISERR(); s = nexts) {
nexts = s->next;
for (a = s->ins; a != NULL && !NISERR(); a = nexta) {
nexta = a->inchain;
if (a->type == '$' || a->type == AHEAD)
if (push(nfa, a))
progress = 1;
assert(nexta == NULL || s->no != FREESTATE);
}
}
if (progress && f != NULL)
dumpnfa(nfa, f);
} while (progress && !NISERR());
if (NISERR())
return;
for (a = nfa->post->ins; a != NULL; a = nexta) {
nexta = a->inchain;
if (a->type == '$') {
assert(a->co == 0 || a->co == 1);
newarc(nfa, PLAIN, nfa->eos[a->co], a->from, a->to);
freearc(nfa, a);
}
}
}
/*
* push - push a forward constraint forward past its destination state
* A significant property of this function is that it deletes at most
* one state -- the constraint's to state -- and only if the constraint
* was that state's last inarc.
*/
static int /* 0 couldn't, 1 could */
push(struct nfa *nfa,
struct arc *con)
{
struct state *from = con->from;
struct state *to = con->to;
struct arc *a;
struct arc *nexta;
struct state *s;
if (to == from) { /* circular constraint is pointless */
freearc(nfa, con);
return 1;
}
if (to->flag) /* can't push forward beyond end */
return 0;
if (to->nouts == 0) { /* dead end */
freearc(nfa, con);
return 1;
}
/* first, clone to state if necessary to avoid other inarcs */
if (to->nins > 1) {
s = newstate(nfa);
if (NISERR())
return 0;
copyouts(nfa, to, s); /* duplicate outarcs */
cparc(nfa, con, from, s); /* move constraint */
freearc(nfa, con);
to = s;
con = to->ins;
}
assert(to->nins == 1);
/* propagate the constraint into the to state's outarcs */
for (a = to->outs; a != NULL; a = nexta) {
nexta = a->outchain;
switch (combine(con, a)) {
case INCOMPATIBLE: /* destroy the arc */
freearc(nfa, a);
break;
case SATISFIED: /* no action needed */
break;
case COMPATIBLE: /* swap the two arcs, more or less */
s = newstate(nfa);
if (NISERR())
return 0;
cparc(nfa, con, s, a->to); /* anticipate move */
cparc(nfa, a, from, s);
if (NISERR())
return 0;
freearc(nfa, a);
break;
default:
assert(NOTREACHED);
break;
}
}
/* remaining outarcs, if any, incorporate the constraint */
moveouts(nfa, to, from);
dropstate(nfa, to); /* will free the constraint */
return 1;
}
/*
* combine - constraint lands on an arc, what happens?
*
* #def INCOMPATIBLE 1 // destroys arc
* #def SATISFIED 2 // constraint satisfied
* #def COMPATIBLE 3 // compatible but not satisfied yet
*/
static int
combine(struct arc *con,
struct arc *a)
{
# define CA(ct,at) (((ct)<<CHAR_BIT) | (at))
switch (CA(con->type, a->type)) {
case CA('^', PLAIN): /* newlines are handled separately */
case CA('$', PLAIN):
return INCOMPATIBLE;
break;
case CA(AHEAD, PLAIN): /* color constraints meet colors */
case CA(BEHIND, PLAIN):
if (con->co == a->co)
return SATISFIED;
return INCOMPATIBLE;
break;
case CA('^', '^'): /* collision, similar constraints */
case CA('$', '$'):
case CA(AHEAD, AHEAD):
case CA(BEHIND, BEHIND):
if (con->co == a->co) /* true duplication */
return SATISFIED;
return INCOMPATIBLE;
break;
case CA('^', BEHIND): /* collision, dissimilar constraints */
case CA(BEHIND, '^'):
case CA('$', AHEAD):
case CA(AHEAD, '$'):
return INCOMPATIBLE;
break;
case CA('^', '$'): /* constraints passing each other */
case CA('^', AHEAD):
case CA(BEHIND, '$'):
case CA(BEHIND, AHEAD):
case CA('$', '^'):
case CA('$', BEHIND):
case CA(AHEAD, '^'):
case CA(AHEAD, BEHIND):
case CA('^', LACON):
case CA(BEHIND, LACON):
case CA('$', LACON):
case CA(AHEAD, LACON):
return COMPATIBLE;
break;
}
assert(NOTREACHED);
return INCOMPATIBLE; /* for benefit of blind compilers */
}
/*
* fixempties - get rid of EMPTY arcs
*/
static void
fixempties(struct nfa *nfa,
FILE *f) /* for debug output; NULL none */
{
struct state *s;
struct state *nexts;
struct arc *a;
struct arc *nexta;
int progress;
/* find and eliminate empties until there are no more */
do {
progress = 0;
for (s = nfa->states; s != NULL && !NISERR(); s = nexts) {
nexts = s->next;
for (a = s->outs; a != NULL && !NISERR(); a = nexta) {
nexta = a->outchain;
if (a->type == EMPTY && unempty(nfa, a))
progress = 1;
assert(nexta == NULL || s->no != FREESTATE);
}
}
if (progress && f != NULL)
dumpnfa(nfa, f);
} while (progress && !NISERR());
}
/*
* unempty - optimize out an EMPTY arc, if possible
*
* Actually, as it stands this function always succeeds, but the return
* value is kept with an eye on possible future changes.
*/
static int /* 0 couldn't, 1 could */
unempty(struct nfa *nfa,
struct arc *a)
{
struct state *from = a->from;
struct state *to = a->to;
int usefrom; /* work on from, as opposed to to? */
assert(a->type == EMPTY);
assert(from != nfa->pre && to != nfa->post);
if (from == to) { /* vacuous loop */
freearc(nfa, a);
return 1;
}
/* decide which end to work on */
usefrom = 1; /* default: attack from */
if (from->nouts > to->nins)
usefrom = 0;
else if (from->nouts == to->nins) {
/* decide on secondary issue: move/copy fewest arcs */
if (from->nins > to->nouts)
usefrom = 0;
}
freearc(nfa, a);
if (usefrom) {
if (from->nouts == 0) {
/* was the state's only outarc */
moveins(nfa, from, to);
freestate(nfa, from);
} else
copyins(nfa, from, to);
} else {
if (to->nins == 0) {
/* was the state's only inarc */
moveouts(nfa, to, from);
freestate(nfa, to);
} else
copyouts(nfa, to, from);
}
return 1;
}
/*
* cleanup - clean up NFA after optimizations
*/
static void
cleanup(struct nfa *nfa)
{
struct state *s;
struct state *nexts;
int n;
/* clear out unreachable or dead-end states */
/* use pre to mark reachable, then post to mark can-reach-post */
markreachable(nfa, nfa->pre, (struct state *)NULL, nfa->pre);
markcanreach(nfa, nfa->post, nfa->pre, nfa->post);
for (s = nfa->states; s != NULL; s = nexts) {
nexts = s->next;
if (s->tmp != nfa->post && !s->flag)
dropstate(nfa, s);
}
assert(nfa->post->nins == 0 || nfa->post->tmp == nfa->post);
cleartraverse(nfa, nfa->pre);
assert(nfa->post->nins == 0 || nfa->post->tmp == NULL);
/* the nins==0 (final unreachable) case will be caught later */
/* renumber surviving states */
n = 0;
for (s = nfa->states; s != NULL; s = s->next)
s->no = n++;
nfa->nstates = n;
}
/*
* markreachable - recursive marking of reachable states
*/
static void
markreachable(struct nfa *nfa,
struct state *s,
struct state *okay, /* consider only states with this mark */
struct state *mark) /* the value to mark with */
{
struct arc *a;
if (s->tmp != okay)
return;
s->tmp = mark;
for (a = s->outs; a != NULL; a = a->outchain)
markreachable(nfa, a->to, okay, mark);
}
/*
* markcanreach - recursive marking of states which can reach here
*/
static void
markcanreach(struct nfa *nfa,
struct state *s,
struct state *okay, /* consider only states with this mark */
struct state *mark) /* the value to mark with */
{
struct arc *a;
if (s->tmp != okay)
return;
s->tmp = mark;
for (a = s->ins; a != NULL; a = a->inchain)
markcanreach(nfa, a->from, okay, mark);
}
/*
* analyze - ascertain potentially-useful facts about an optimized NFA
*/
static long /* re_info bits to be ORed in */
analyze(struct nfa *nfa)
{
struct arc *a;
struct arc *aa;
if (nfa->pre->outs == NULL)
return REG_UIMPOSSIBLE;
for (a = nfa->pre->outs; a != NULL; a = a->outchain)
for (aa = a->to->outs; aa != NULL; aa = aa->outchain)
if (aa->to == nfa->post)
return REG_UEMPTYMATCH;
return 0;
}
/*
* compact - compact an NFA
*/
static void
compact(struct nfa *nfa,
struct cnfa *cnfa)
{
struct state *s;
struct arc *a;
size_t nstates;
size_t narcs;
struct carc *ca;
struct carc *first;
assert (!NISERR());
nstates = 0;
narcs = 0;
for (s = nfa->states; s != NULL; s = s->next) {
nstates++;
narcs += 1 + s->nouts + 1;
/* 1 as a fake for flags, nouts for arcs, 1 as endmarker */
}
cnfa->states = (struct carc **)MALLOC(nstates * sizeof(struct carc *));
cnfa->arcs = (struct carc *)MALLOC(narcs * sizeof(struct carc));
if (cnfa->states == NULL || cnfa->arcs == NULL) {
if (cnfa->states != NULL)
FREE(cnfa->states);
if (cnfa->arcs != NULL)
FREE(cnfa->arcs);
NERR(REG_ESPACE);
return;
}
cnfa->nstates = nstates;
cnfa->pre = nfa->pre->no;
cnfa->post = nfa->post->no;
cnfa->bos[0] = nfa->bos[0];
cnfa->bos[1] = nfa->bos[1];
cnfa->eos[0] = nfa->eos[0];
cnfa->eos[1] = nfa->eos[1];
cnfa->ncolors = maxcolor(nfa->cm) + 1;
cnfa->flags = 0;
ca = cnfa->arcs;
for (s = nfa->states; s != NULL; s = s->next) {
assert((size_t)s->no < nstates);
cnfa->states[s->no] = ca;
ca->co = 0; /* clear and skip flags "arc" */
ca++;
first = ca;
for (a = s->outs; a != NULL; a = a->outchain)
switch (a->type) {
case PLAIN:
ca->co = a->co;
ca->to = a->to->no;
ca++;
break;
case LACON:
assert(s->no != cnfa->pre);
ca->co = (color)(cnfa->ncolors + a->co);
ca->to = a->to->no;
ca++;
cnfa->flags |= HASLACONS;
break;
default:
assert(NOTREACHED);
break;
}
carcsort(first, ca-1);
ca->co = COLORLESS;
ca->to = 0;
ca++;
}
assert(ca == &cnfa->arcs[narcs]);
assert(cnfa->nstates != 0);
/* mark no-progress states */
for (a = nfa->pre->outs; a != NULL; a = a->outchain)
cnfa->states[a->to->no]->co = 1;
cnfa->states[nfa->pre->no]->co = 1;
}
/*
* carcsort - sort compacted-NFA arcs by color
*
* Really dumb algorithm, but if the list is long enough for that to matter,
* you're in real trouble anyway.
*/
static void
carcsort(struct carc *first,
struct carc *last)
{
struct carc *p;
struct carc *q;
struct carc tmp;
if (last - first <= 1)
return;
for (p = first; p <= last; p++)
for (q = p; q <= last; q++)
if (p->co > q->co ||
(p->co == q->co && p->to > q->to)) {
assert(p != q);
tmp = *p;
*p = *q;
*q = tmp;
}
}
/*
* freecnfa - free a compacted NFA
*/
static void
freecnfa(struct cnfa *cnfa)
{
assert(cnfa->nstates != 0); /* not empty already */
cnfa->nstates = 0;
FREE(cnfa->states);
FREE(cnfa->arcs);
}
/*
* dumpnfa - dump an NFA in human-readable form
*/
static void
dumpnfa(struct nfa *nfa,
FILE *f)
{
#ifdef REG_DEBUG
struct state *s;
fprintf(f, "pre %d, post %d", nfa->pre->no, nfa->post->no);
if (nfa->bos[0] != COLORLESS)
fprintf(f, ", bos [%ld]", (long)nfa->bos[0]);
if (nfa->bos[1] != COLORLESS)
fprintf(f, ", bol [%ld]", (long)nfa->bos[1]);
if (nfa->eos[0] != COLORLESS)
fprintf(f, ", eos [%ld]", (long)nfa->eos[0]);
if (nfa->eos[1] != COLORLESS)
fprintf(f, ", eol [%ld]", (long)nfa->eos[1]);
fprintf(f, "\n");
for (s = nfa->states; s != NULL; s = s->next)
dumpstate(s, f);
if (nfa->parent == NULL)
dumpcolors(nfa->cm, f);
fflush(f);
#endif
}
#ifdef REG_DEBUG /* subordinates of dumpnfa */
/*
* dumpstate - dump an NFA state in human-readable form
*/
static void
dumpstate(struct state *s,
FILE *f)
{
struct arc *a;
fprintf(f, "%d%s%c", s->no, (s->tmp != NULL) ? "T" : "",
(s->flag) ? s->flag : '.');
if (s->prev != NULL && s->prev->next != s)
fprintf(f, "\tstate chain bad\n");
if (s->nouts == 0)
fprintf(f, "\tno out arcs\n");
else
dumparcs(s, f);
fflush(f);
for (a = s->ins; a != NULL; a = a->inchain) {
if (a->to != s)
fprintf(f, "\tlink from %d to %d on %d's in-chain\n",
a->from->no, a->to->no, s->no);
}
}
/*
* dumparcs - dump out-arcs in human-readable form
*/
static void
dumparcs(struct state *s,
FILE *f)
{
int pos;
assert(s->nouts > 0);
/* printing arcs in reverse order is usually clearer */
pos = dumprarcs(s->outs, s, f, 1);
if (pos != 1)
fprintf(f, "\n");
}
/*
* dumprarcs - dump remaining outarcs, recursively, in reverse order
*/
static int /* resulting print position */
dumprarcs(struct arc *a,
struct state *s,
FILE *f,
int pos) /* initial print position */
{
if (a->outchain != NULL)
pos = dumprarcs(a->outchain, s, f, pos);
dumparc(a, s, f);
if (pos == 5) {
fprintf(f, "\n");
pos = 1;
} else
pos++;
return pos;
}
/*
* dumparc - dump one outarc in readable form, including prefixing tab
*/
static void
dumparc(struct arc *a,
struct state *s,
FILE *f)
{
struct arc *aa;
struct arcbatch *ab;
fprintf(f, "\t");
switch (a->type) {
case PLAIN:
fprintf(f, "[%ld]", (long)a->co);
break;
case AHEAD:
fprintf(f, ">%ld>", (long)a->co);
break;
case BEHIND:
fprintf(f, "<%ld<", (long)a->co);
break;
case LACON:
fprintf(f, ":%ld:", (long)a->co);
break;
case '^':
case '$':
fprintf(f, "%c%d", a->type, (int)a->co);
break;
case EMPTY:
break;
default:
fprintf(f, "0x%x/0%lo", a->type, (long)a->co);
break;
}
if (a->from != s)
fprintf(f, "?%d?", a->from->no);
for (ab = &a->from->oas; ab != NULL; ab = ab->next) {
for (aa = &ab->a[0]; aa < &ab->a[ABSIZE]; aa++)
if (aa == a)
break; /* NOTE BREAK OUT */
if (aa < &ab->a[ABSIZE]) /* propagate break */
break; /* NOTE BREAK OUT */
}
if (ab == NULL)
fprintf(f, "?!?"); /* not in allocated space */
fprintf(f, "->");
if (a->to == NULL) {
fprintf(f, "NULL");
return;
}
fprintf(f, "%d", a->to->no);
for (aa = a->to->ins; aa != NULL; aa = aa->inchain)
if (aa == a)
break; /* NOTE BREAK OUT */
if (aa == NULL)
fprintf(f, "?!?"); /* missing from in-chain */
}
#endif /* REG_DEBUG */
/*
* dumpcnfa - dump a compacted NFA in human-readable form
*/
#ifdef REG_DEBUG
static void
dumpcnfa(struct cnfa *cnfa,
FILE *f)
{
int st;
fprintf(f, "pre %d, post %d", cnfa->pre, cnfa->post);
if (cnfa->bos[0] != COLORLESS)
fprintf(f, ", bos [%ld]", (long)cnfa->bos[0]);
if (cnfa->bos[1] != COLORLESS)
fprintf(f, ", bol [%ld]", (long)cnfa->bos[1]);
if (cnfa->eos[0] != COLORLESS)
fprintf(f, ", eos [%ld]", (long)cnfa->eos[0]);
if (cnfa->eos[1] != COLORLESS)
fprintf(f, ", eol [%ld]", (long)cnfa->eos[1]);
if (cnfa->flags&HASLACONS)
fprintf(f, ", haslacons");
fprintf(f, "\n");
for (st = 0; st < cnfa->nstates; st++)
dumpcstate(st, cnfa->states[st], cnfa, f);
fflush(f);
}
#endif
#ifdef REG_DEBUG /* subordinates of dumpcnfa */
/*
* dumpcstate - dump a compacted-NFA state in human-readable form
*/
static void
dumpcstate(int st,
struct carc *ca,
struct cnfa *cnfa,
FILE *f)
{
int i;
int pos;
fprintf(f, "%d%s", st, (ca[0].co) ? ":" : ".");
pos = 1;
for (i = 1; ca[i].co != COLORLESS; i++) {
if (ca[i].co < cnfa->ncolors)
fprintf(f, "\t[%ld]->%d", (long)ca[i].co, ca[i].to);
else
fprintf(f, "\t:%ld:->%d", (long)ca[i].co-cnfa->ncolors,
ca[i].to);
if (pos == 5) {
fprintf(f, "\n");
pos = 1;
} else
pos++;
}
if (i == 1 || pos != 1)
fprintf(f, "\n");
fflush(f);
}
#endif /* REG_DEBUG */
src/backend/regex/regcomp.c
View file @ 7bcc6d98
/*- /*
* Copyright (c) 1992, 1993, 1994 Henry Spencer. * re_*comp and friends - compile REs
* Copyright (c) 1992, 1993, 1994 * This file #includes several others (see the bottom).
* The Regents of the University of California. All rights reserved. *
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
* *
* This code is derived from software contributed to Berkeley by * Redistribution and use in source and binary forms -- with or without
* Henry Spencer. * modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
* *
* Redistribution and use in source and binary forms, with or without * I'd appreciate being given credit for this package in the documentation
* modification, are permitted provided that the following conditions * of software which uses it, but that is not a requirement.
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* SUCH DAMAGE. *
* $Header: /cvsroot/pgsql/src/backend/regex/regcomp.c,v 1.36 2003/02/05 17:41:33 tgl Exp $
* *
* @(#)regcomp.c 8.5 (Berkeley) 3/20/94
*/ */
#include "postgres.h" #include "regex/regguts.h"
#include <ctype.h>
#include <limits.h>
#include <assert.h>
#include "regex/regex.h"
#include "regex/utils.h"
#include "regex/regex2.h"
#include "regex/cname.h"
struct cclass
{
char *name;
char *chars;
char *multis;
};
static struct cclass *cclasses = NULL;
static struct cclass *cclass_init(void);
/* /*
* parse structure, passed up and down to avoid global variables and * forward declarations, up here so forward datatypes etc. are defined early
* other clumsinesses
*/ */
struct parse /* === regcomp.c === */
{ static void moresubs (struct vars *, int);
pg_wchar *next; /* next character in RE */ static int freev (struct vars *, int);
pg_wchar *end; /* end of string (-> NUL normally) */ static void makesearch (struct vars *, struct nfa *);
int error; /* has an error been seen? */ static struct subre *parse (struct vars *, int, int, struct state *, struct state *);
sop *strip; /* malloced strip */ static struct subre *parsebranch (struct vars *, int, int, struct state *, struct state *, int);
sopno ssize; /* malloced strip size (allocated) */ static void parseqatom (struct vars *, int, int, struct state *, struct state *, struct subre *);
sopno slen; /* malloced strip length (used) */ static void nonword (struct vars *, int, struct state *, struct state *);
int ncsalloc; /* number of csets allocated */ static void word (struct vars *, int, struct state *, struct state *);
struct re_guts *g; static int scannum (struct vars *);
#define NPAREN 10 /* we need to remember () 1-9 for back static void repeat (struct vars *, struct state *, struct state *, int, int);
* refs */ static void bracket (struct vars *, struct state *, struct state *);
sopno pbegin[NPAREN]; /* -> ( ([0] unused) */ static void cbracket (struct vars *, struct state *, struct state *);
sopno pend[NPAREN]; /* -> ) ([0] unused) */ static void brackpart (struct vars *, struct state *, struct state *);
static chr *scanplain (struct vars *);
static void leaders (struct vars *, struct cvec *);
static void onechr (struct vars *, chr, struct state *, struct state *);
static void dovec (struct vars *, struct cvec *, struct state *, struct state *);
static celt nextleader (struct vars *, chr, chr);
static void wordchrs (struct vars *);
static struct subre *subre (struct vars *, int, int, struct state *, struct state *);
static void freesubre (struct vars *, struct subre *);
static void freesrnode (struct vars *, struct subre *);
static void optst (struct vars *, struct subre *);
static int numst (struct subre *, int);
static void markst (struct subre *);
static void cleanst (struct vars *);
static long nfatree (struct vars *, struct subre *, FILE *);
static long nfanode (struct vars *, struct subre *, FILE *);
static int newlacon (struct vars *, struct state *, struct state *, int);
static void freelacons (struct subre *, int);
static void rfree (regex_t *);
#ifdef REG_DEBUG
static void dump (regex_t *, FILE *);
static void dumpst (struct subre *, FILE *, int);
static void stdump (struct subre *, FILE *, int);
static char *stid (struct subre *, char *, size_t);
#endif
/* === regc_lex.c === */
static void lexstart (struct vars *);
static void prefixes (struct vars *);
static void lexnest (struct vars *, chr *, chr *);
static void lexword (struct vars *);
static int next (struct vars *);
static int lexescape (struct vars *);
static chr lexdigits (struct vars *, int, int, int);
static int brenext (struct vars *, chr);
static void skip (struct vars *);
static chr newline (void);
static chr chrnamed (struct vars *, chr *, chr *, chr);
/* === regc_color.c === */
static void initcm (struct vars *, struct colormap *);
static void freecm (struct colormap *);
static void cmtreefree (struct colormap *, union tree *, int);
static color setcolor (struct colormap *, chr, pcolor);
static color maxcolor (struct colormap *);
static color newcolor (struct colormap *);
static void freecolor (struct colormap *, pcolor);
static color pseudocolor (struct colormap *);
static color subcolor (struct colormap *, chr c);
static color newsub (struct colormap *, pcolor);
static void subrange (struct vars *, chr, chr, struct state *, struct state *);
static void subblock (struct vars *, chr, struct state *, struct state *);
static void okcolors (struct nfa *, struct colormap *);
static void colorchain (struct colormap *, struct arc *);
static void uncolorchain (struct colormap *, struct arc *);
static int singleton (struct colormap *, chr c);
static void rainbow (struct nfa *, struct colormap *, int, pcolor, struct state *, struct state *);
static void colorcomplement (struct nfa *, struct colormap *, int, struct state *, struct state *, struct state *);
#ifdef REG_DEBUG
static void dumpcolors (struct colormap *, FILE *);
static void fillcheck (struct colormap *, union tree *, int, FILE *);
static void dumpchr (chr, FILE *);
#endif
/* === regc_nfa.c === */
static struct nfa *newnfa (struct vars *, struct colormap *, struct nfa *);
static void freenfa (struct nfa *);
static struct state *newstate (struct nfa *);
static struct state *newfstate (struct nfa *, int flag);
static void dropstate (struct nfa *, struct state *);
static void freestate (struct nfa *, struct state *);
static void destroystate (struct nfa *, struct state *);
static void newarc (struct nfa *, int, pcolor, struct state *, struct state *);
static struct arc *allocarc (struct nfa *, struct state *);
static void freearc (struct nfa *, struct arc *);
static struct arc *findarc (struct state *, int, pcolor);
static void cparc (struct nfa *, struct arc *, struct state *, struct state *);
static void moveins (struct nfa *, struct state *, struct state *);
static void copyins (struct nfa *, struct state *, struct state *);
static void moveouts (struct nfa *, struct state *, struct state *);
static void copyouts (struct nfa *, struct state *, struct state *);
static void cloneouts (struct nfa *, struct state *, struct state *, struct state *, int);
static void delsub (struct nfa *, struct state *, struct state *);
static void deltraverse (struct nfa *, struct state *, struct state *);
static void dupnfa (struct nfa *, struct state *, struct state *, struct state *, struct state *);
static void duptraverse (struct nfa *, struct state *, struct state *);
static void cleartraverse (struct nfa *, struct state *);
static void specialcolors (struct nfa *);
static long optimize (struct nfa *, FILE *);
static void pullback (struct nfa *, FILE *);
static int pull (struct nfa *, struct arc *);
static void pushfwd (struct nfa *, FILE *);
static int push (struct nfa *, struct arc *);
#define INCOMPATIBLE 1 /* destroys arc */
#define SATISFIED 2 /* constraint satisfied */
#define COMPATIBLE 3 /* compatible but not satisfied yet */
static int combine (struct arc *, struct arc *);
static void fixempties (struct nfa *, FILE *);
static int unempty (struct nfa *, struct arc *);
static void cleanup (struct nfa *);
static void markreachable (struct nfa *, struct state *, struct state *, struct state *);
static void markcanreach (struct nfa *, struct state *, struct state *, struct state *);
static long analyze (struct nfa *);
static void compact (struct nfa *, struct cnfa *);
static void carcsort (struct carc *, struct carc *);
static void freecnfa (struct cnfa *);
static void dumpnfa (struct nfa *, FILE *);
#ifdef REG_DEBUG
static void dumpstate (struct state *, FILE *);
static void dumparcs (struct state *, FILE *);
static int dumprarcs (struct arc *, struct state *, FILE *, int);
static void dumparc (struct arc *, struct state *, FILE *);
static void dumpcnfa (struct cnfa *, FILE *);
static void dumpcstate (int, struct carc *, struct cnfa *, FILE *);
#endif
/* === regc_cvec.c === */
static struct cvec *newcvec (int, int, int);
static struct cvec *clearcvec (struct cvec *);
static void addchr (struct cvec *, chr);
static void addrange (struct cvec *, chr, chr);
static void addmcce (struct cvec *, chr *, chr *);
static int haschr (struct cvec *, chr);
static struct cvec *getcvec (struct vars *, int, int, int);
static void freecvec (struct cvec *);
/* === regc_locale.c === */
static int pg_isdigit(pg_wchar c);
static int pg_isalpha(pg_wchar c);
static int pg_isalnum(pg_wchar c);
static int pg_isupper(pg_wchar c);
static int pg_islower(pg_wchar c);
static int pg_isgraph(pg_wchar c);
static int pg_ispunct(pg_wchar c);
static int pg_isspace(pg_wchar c);
static pg_wchar pg_toupper(pg_wchar c);
static pg_wchar pg_tolower(pg_wchar c);
static int nmcces (struct vars *);
static int nleaders (struct vars *);
static struct cvec *allmcces (struct vars *, struct cvec *);
static celt element (struct vars *, chr *, chr *);
static struct cvec *range (struct vars *, celt, celt, int);
static int before (celt, celt);
static struct cvec *eclass (struct vars *, celt, int);
static struct cvec *cclass (struct vars *, chr *, chr *, int);
static struct cvec *allcases (struct vars *, chr);
static int cmp (const chr *, const chr *, size_t);
static int casecmp (const chr *, const chr *, size_t);
/* internal variables, bundled for easy passing around */
struct vars {
regex_t *re;
chr *now; /* scan pointer into string */
chr *stop; /* end of string */
chr *savenow; /* saved now and stop for "subroutine call" */
chr *savestop;
int err; /* error code (0 if none) */
int cflags; /* copy of compile flags */
int lasttype; /* type of previous token */
int nexttype; /* type of next token */
chr nextvalue; /* value (if any) of next token */
int lexcon; /* lexical context type (see lex.c) */
int nsubexp; /* subexpression count */
struct subre **subs; /* subRE pointer vector */
size_t nsubs; /* length of vector */
struct subre *sub10[10]; /* initial vector, enough for most */
struct nfa *nfa; /* the NFA */
struct colormap *cm; /* character color map */
color nlcolor; /* color of newline */
struct state *wordchrs; /* state in nfa holding word-char outarcs */
struct subre *tree; /* subexpression tree */
struct subre *treechain; /* all tree nodes allocated */
struct subre *treefree; /* any free tree nodes */
int ntree; /* number of tree nodes */
struct cvec *cv; /* interface cvec */
struct cvec *cv2; /* utility cvec */
struct cvec *mcces; /* collating-element information */
# define ISCELEADER(v,c) (v->mcces != NULL && haschr(v->mcces, (c)))
struct state *mccepbegin; /* in nfa, start of MCCE prototypes */
struct state *mccepend; /* in nfa, end of MCCE prototypes */
struct subre *lacons; /* lookahead-constraint vector */
int nlacons; /* size of lacons */
}; };
static void p_ere(struct parse * p, int stop); /* parsing macros; most know that `v' is the struct vars pointer */
static void p_ere_exp(struct parse * p); #define NEXT() (next(v)) /* advance by one token */
static void p_str(struct parse * p); #define SEE(t) (v->nexttype == (t)) /* is next token this? */
static void p_bre(struct parse * p, int end1, int end2); #define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */
static int p_simp_re(struct parse * p, int starordinary); #define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
static int p_count(struct parse * p); #define ISERR() VISERR(v)
static void p_bracket(struct parse * p); #define VERR(vv,e) ((vv)->nexttype = EOS, ((vv)->err) ? (vv)->err :\
static void p_b_term(struct parse * p, cset *cs); ((vv)->err = (e)))
static void p_b_cclass(struct parse * p, cset *cs); #define ERR(e) VERR(v, e) /* record an error */
static void p_b_eclass(struct parse * p, cset *cs); #define NOERR() {if (ISERR()) return;} /* if error seen, return */
static pg_wchar p_b_symbol(struct parse * p); #define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */
static char p_b_coll_elem(struct parse * p, int endc); #define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */
static unsigned char othercase(int ch); #define INSIST(c, e) ((c) ? 0 : ERR(e)) /* if condition false, error */
static void bothcases(struct parse * p, int ch); #define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
static void ordinary(struct parse * p, int ch); #define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
static void nonnewline(struct parse * p);
static void repeat(struct parse * p, sopno start, int from, int to); /* token type codes, some also used as NFA arc types */
static int seterr(struct parse * p, int e); #define EMPTY 'n' /* no token present */
static cset *allocset(struct parse * p); #define EOS 'e' /* end of string */
static void freeset(struct parse * p, cset *cs); #define PLAIN 'p' /* ordinary character */
static int freezeset(struct parse * p, cset *cs); #define DIGIT 'd' /* digit (in bound) */
static int firstch(struct parse * p, cset *cs); #define BACKREF 'b' /* back reference */
static int nch(struct parse * p, cset *cs); #define COLLEL 'I' /* start of [. */
static void mcadd(struct parse * p, cset *cs, char *cp); #define ECLASS 'E' /* start of [= */
static void mcinvert(struct parse * p, cset *cs); #define CCLASS 'C' /* start of [: */
static void mccase(struct parse * p, cset *cs); #define END 'X' /* end of [. [= [: */
static int isinsets(struct re_guts * g, int c); #define RANGE 'R' /* - within [] which might be range delim. */
static int samesets(struct re_guts * g, int c1, int c2); #define LACON 'L' /* lookahead constraint subRE */
static void categorize(struct parse * p, struct re_guts * g); #define AHEAD 'a' /* color-lookahead arc */
static sopno dupl(struct parse * p, sopno start, sopno finish); #define BEHIND 'r' /* color-lookbehind arc */
static void doemit(struct parse * p, sop op, size_t opnd); #define WBDRY 'w' /* word boundary constraint */
static void doinsert(struct parse * p, sop op, size_t opnd, sopno pos); #define NWBDRY 'W' /* non-word-boundary constraint */
static void dofwd(struct parse * p, sopno pos, sop value); #define SBEGIN 'A' /* beginning of string (even if not BOL) */
static void enlarge(struct parse * p, sopno size); #define SEND 'Z' /* end of string (even if not EOL) */
static void stripsnug(struct parse * p, struct re_guts * g); #define PREFER 'P' /* length preference */
static void findmust(struct parse * p, struct re_guts * g);
static sopno pluscount(struct parse * p, struct re_guts * g); /* is an arc colored, and hence on a color chain? */
static int pg_isdigit(int c); #define COLORED(a) ((a)->type == PLAIN || (a)->type == AHEAD || \
static int pg_isalpha(int c); (a)->type == BEHIND)
static int pg_isalnum(int c);
static int pg_isupper(int c);
static int pg_islower(int c);
static int pg_iscntrl(int c); /* static function list */
static int pg_isgraph(int c); static struct fns functions = {
static int pg_isprint(int c); rfree, /* regfree insides */
static int pg_ispunct(int c); };
static pg_wchar nuls[10]; /* place to point scanner in event of
* error */
/*
* macros for use with parse structure
* BEWARE: these know that the parse structure is named `p' !!!
*/
#define PEEK() (*p->next)
#define PEEK2() (*(p->next+1))
#define MORE() (p->next < p->end)
#define MORE2() (p->next+1 < p->end)
#define SEE(c) (MORE() && PEEK() == (c))
#define SEETWO(a, b) (MORE() && MORE2() && PEEK() == (a) && PEEK2() == (b))
#define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0)
#define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0)
#define NEXT() (p->next++)
#define NEXT2() (p->next += 2)
#define NEXTn(n) (p->next += (n))
#define GETNEXT() (*p->next++)
#define SETERROR(e) seterr(p, (e))
#define REQUIRE(co, e) if (!(co)) SETERROR(e)
#define MUSTSEE(c, e) REQUIRE(MORE() && PEEK() == (c), e)
#define MUSTEAT(c, e) REQUIRE(MORE() && GETNEXT() == (c), e)
#define MUSTNOTSEE(c, e) REQUIRE(!MORE() || PEEK() != (c), e)
#define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd))
#define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos)
#define AHEAD(pos) dofwd(p, pos, HERE()-(pos))
#define ASTERN(sop, pos) EMIT(sop, HERE()-pos)
#define HERE() (p->slen)
#define THERE() (p->slen - 1)
#define THERETHERE() (p->slen - 2)
#define DROP(n) (p->slen -= (n))
#ifndef NDEBUG
static int never = 0; /* for use in asserts; shuts lint up */
#else
#define never 0 /* some <assert.h>s have bugs too */
#endif
/* /*
* regcomp - interface for parser and compilation * pg_regcomp - compile regular expression
* returns 0 success, otherwise REG_something
*/ */
int int
pg_regcomp(regex_t *preg, const char *pattern, int cflags) pg_regcomp(regex_t *re,
const chr *string,
size_t len,
int flags)
{ {
struct parse pa; struct vars var;
struct re_guts *g; struct vars *v = &var;
struct parse *p = &pa; struct guts *g;
int i; int i;
size_t len; size_t j;
pg_wchar *wcp; #ifdef REG_DEBUG
FILE *debug = (flags&REG_PROGRESS) ? stdout : (FILE *)NULL;
if (cclasses == NULL)
cclasses = cclass_init();
#ifdef REDEBUG
#define GOODFLAGS(f) (f)
#else #else
#define GOODFLAGS(f) ((f)&~REG_DUMP) FILE *debug = (FILE *) NULL;
#endif #endif
cflags = GOODFLAGS(cflags); # define CNOERR() { if (ISERR()) return freev(v, v->err); }
if ((cflags & REG_EXTENDED) && (cflags & REG_NOSPEC))
return REG_INVARG;
if (cflags & REG_PEND) /* sanity checks */
{
wcp = preg->patsave; if (re == NULL || string == NULL)
if (preg->re_endp < wcp)
return REG_INVARG; return REG_INVARG;
len = preg->re_endp - wcp; if ((flags&REG_QUOTE) &&
(flags&(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE)))
return REG_INVARG;
if (!(flags&REG_EXTENDED) && (flags&REG_ADVF))
return REG_INVARG;
/* initial setup (after which freev() is callable) */
v->re = re;
v->now = (chr *)string;
v->stop = v->now + len;
v->savenow = v->savestop = NULL;
v->err = 0;
v->cflags = flags;
v->nsubexp = 0;
v->subs = v->sub10;
v->nsubs = 10;
for (j = 0; j < v->nsubs; j++)
v->subs[j] = NULL;
v->nfa = NULL;
v->cm = NULL;
v->nlcolor = COLORLESS;
v->wordchrs = NULL;
v->tree = NULL;
v->treechain = NULL;
v->treefree = NULL;
v->cv = NULL;
v->cv2 = NULL;
v->mcces = NULL;
v->lacons = NULL;
v->nlacons = 0;
re->re_magic = REMAGIC;
re->re_info = 0; /* bits get set during parse */
re->re_csize = sizeof(chr);
re->re_guts = NULL;
re->re_fns = VS(&functions);
/* more complex setup, malloced things */
re->re_guts = VS(MALLOC(sizeof(struct guts)));
if (re->re_guts == NULL)
return freev(v, REG_ESPACE);
g = (struct guts *)re->re_guts;
g->tree = NULL;
initcm(v, &g->cmap);
v->cm = &g->cmap;
g->lacons = NULL;
g->nlacons = 0;
ZAPCNFA(g->search);
v->nfa = newnfa(v, v->cm, (struct nfa *)NULL);
CNOERR();
v->cv = newcvec(100, 20, 10);
if (v->cv == NULL)
return freev(v, REG_ESPACE);
i = nmcces(v);
if (i > 0) {
v->mcces = newcvec(nleaders(v), 0, i);
CNOERR();
v->mcces = allmcces(v, v->mcces);
leaders(v, v->mcces);
addmcce(v->mcces, (chr *)NULL, (chr *)NULL); /* dummy */
} }
else CNOERR();
{
wcp = (pg_wchar *) malloc((strlen(pattern) + 1) * sizeof(pg_wchar)); /* parsing */
if (wcp == NULL) lexstart(v); /* also handles prefixes */
return REG_ESPACE; if ((v->cflags&REG_NLSTOP) || (v->cflags&REG_NLANCH)) {
preg->patsave = wcp; /* assign newline a unique color */
(void) pg_mb2wchar((unsigned char *) pattern, wcp); v->nlcolor = subcolor(v->cm, newline());
len = pg_wchar_strlen(wcp); okcolors(v->nfa, v->cm);
}
/* do the mallocs early so failure handling is easy */
g = (struct re_guts *) malloc(sizeof(struct re_guts) +
(NC - 1) * sizeof(cat_t));
if (g == NULL)
return REG_ESPACE;
p->ssize = len / (size_t) 2 *(size_t) 3 + (size_t) 1; /* ugh */
p->strip = (sop *) malloc(p->ssize * sizeof(sop));
p->slen = 0;
if (p->strip == NULL)
{
free((char *) g);
return REG_ESPACE;
} }
CNOERR();
/* set things up */ v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final);
p->g = g; assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */
p->next = wcp; CNOERR();
p->end = p->next + len; assert(v->tree != NULL);
p->error = 0;
p->ncsalloc = 0; /* finish setup of nfa and its subre tree */
for (i = 0; i < NPAREN; i++) specialcolors(v->nfa);
{ CNOERR();
p->pbegin[i] = 0; #ifdef REG_DEBUG
p->pend[i] = 0; if (debug != NULL) {
} fprintf(debug, "\n\n\n========= RAW ==========\n");
g->csetsize = NC; dumpnfa(v->nfa, debug);
g->sets = NULL; dumpst(v->tree, debug, 1);
g->setbits = NULL;
g->ncsets = 0;
g->cflags = cflags;
g->iflags = 0;
g->nbol = 0;
g->neol = 0;
g->must = NULL;
g->mlen = 0;
g->nsub = 0;
g->ncategories = 1; /* category 0 is "everything else" */
g->categories = &g->catspace[-(CHAR_MIN)];
memset((char *) g->catspace, 0, NC * sizeof(cat_t));
g->backrefs = 0;
/* do it */
EMIT(OEND, 0);
g->firststate = THERE();
if (cflags & REG_EXTENDED)
p_ere(p, OUT);
else if (cflags & REG_NOSPEC)
p_str(p);
else
p_bre(p, OUT, OUT);
EMIT(OEND, 0);
g->laststate = THERE();
/* tidy up loose ends and fill things in */
categorize(p, g);
stripsnug(p, g);
findmust(p, g);
g->nplus = pluscount(p, g);
g->magic = MAGIC2;
preg->re_nsub = g->nsub;
preg->re_g = g;
preg->re_magic = MAGIC1;
#ifndef REDEBUG
/* not debugging, so can't rely on the assert() in regexec() */
if (g->iflags & BAD)
SETERROR(REG_ASSERT);
#endif
/* win or lose, we're done */
if (p->error != 0) /* lose */
pg_regfree(preg);
return p->error;
}
/*
* p_ere - ERE parser top level, concatenation and alternation
*/
static void
p_ere(struct parse * p,
int stop) /* character this ERE should end at */
{
char c;
sopno prevback = 0;
sopno prevfwd = 0;
sopno conc;
int first = 1; /* is this the first alternative? */
for (;;)
{
/* do a bunch of concatenated expressions */
conc = HERE();
while (MORE() && (c = PEEK()) != '|' && c != stop)
p_ere_exp(p);
REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */
if (!EAT('|'))
break; /* NOTE BREAK OUT */
if (first)
{
INSERT(OCH_, conc); /* offset is wrong */
prevfwd = conc;
prevback = conc;
first = 0;
} }
ASTERN(OOR1, prevback); #endif
prevback = THERE(); optst(v, v->tree);
AHEAD(prevfwd); /* fix previous offset */ v->ntree = numst(v->tree, 1);
prevfwd = HERE(); markst(v->tree);
EMIT(OOR2, 0); /* offset is very wrong */ cleanst(v);
#ifdef REG_DEBUG
if (debug != NULL) {
fprintf(debug, "\n\n\n========= TREE FIXED ==========\n");
dumpst(v->tree, debug, 1);
} }
#endif
if (!first) /* build compacted NFAs for tree and lacons */
{ /* tail-end fixups */ re->re_info |= nfatree(v, v->tree, debug);
AHEAD(prevfwd); CNOERR();
ASTERN(O_CH, prevback); assert(v->nlacons == 0 || v->lacons != NULL);
for (i = 1; i < v->nlacons; i++) {
#ifdef REG_DEBUG
if (debug != NULL)
fprintf(debug, "\n\n\n========= LA%d ==========\n", i);
#endif
nfanode(v, &v->lacons[i], debug);
} }
CNOERR();
if (v->tree->flags&SHORTER)
NOTE(REG_USHORTEST);
/* build compacted NFAs for tree, lacons, fast search */
#ifdef REG_DEBUG
if (debug != NULL)
fprintf(debug, "\n\n\n========= SEARCH ==========\n");
#endif
/* can sacrifice main NFA now, so use it as work area */
(DISCARD)optimize(v->nfa, debug);
CNOERR();
makesearch(v, v->nfa);
CNOERR();
compact(v->nfa, &g->search);
CNOERR();
/* looks okay, package it up */
re->re_nsub = v->nsubexp;
v->re = NULL; /* freev no longer frees re */
g->magic = GUTSMAGIC;
g->cflags = v->cflags;
g->info = re->re_info;
g->nsub = re->re_nsub;
g->tree = v->tree;
v->tree = NULL;
g->ntree = v->ntree;
g->compare = (v->cflags&REG_ICASE) ? casecmp : cmp;
g->lacons = v->lacons;
v->lacons = NULL;
g->nlacons = v->nlacons;
#ifdef REG_DEBUG
if (flags&REG_DUMP)
dump(re, stdout);
#endif
assert(!MORE() || SEE(stop)); assert(v->err == 0);
return freev(v, 0);
} }
/* /*
* p_ere_exp - parse one subERE, an atom possibly followed by a repetition op * moresubs - enlarge subRE vector
*/ */
static void static void
p_ere_exp(struct parse * p) moresubs(struct vars *v,
int wanted) /* want enough room for this one */
{ {
pg_wchar c; struct subre **p;
sopno pos; size_t n;
int count;
int count2; assert(wanted > 0 && (size_t)wanted >= v->nsubs);
sopno subno; n = (size_t)wanted * 3 / 2 + 1;
int wascaret = 0; if (v->subs == v->sub10) {
p = (struct subre **)MALLOC(n * sizeof(struct subre *));
assert(MORE()); /* caller should have ensured this */ if (p != NULL)
c = GETNEXT(); memcpy(VS(p), VS(v->subs),
v->nsubs * sizeof(struct subre *));
pos = HERE(); } else
switch (c) p = (struct subre **)REALLOC(v->subs, n*sizeof(struct subre *));
{ if (p == NULL) {
case '(': ERR(REG_ESPACE);
REQUIRE(MORE(), REG_EPAREN);
p->g->nsub++;
subno = p->g->nsub;
if (subno < NPAREN)
p->pbegin[subno] = HERE();
EMIT(OLPAREN, subno);
if (!SEE(')'))
p_ere(p, ')');
if (subno < NPAREN)
{
p->pend[subno] = HERE();
assert(p->pend[subno] != 0);
}
EMIT(ORPAREN, subno);
MUSTEAT(')', REG_EPAREN);
break;
#ifndef POSIX_MISTAKE
case ')': /* happens only if no current unmatched ( */
/*
* You may ask, why the ifndef? Because I didn't notice this
* until slightly too late for 1003.2, and none of the other
* 1003.2 regular-expression reviewers noticed it at all. So
* an unmatched ) is legal POSIX, at least until we can get it
* fixed.
*/
SETERROR(REG_EPAREN);
break;
#endif
case '^':
EMIT(OBOL, 0);
p->g->iflags |= USEBOL;
p->g->nbol++;
wascaret = 1;
break;
case '$':
EMIT(OEOL, 0);
p->g->iflags |= USEEOL;
p->g->neol++;
break;
case '|':
SETERROR(REG_EMPTY);
break;
case '*':
case '+':
case '?':
SETERROR(REG_BADRPT);
break;
case '.':
if (p->g->cflags & REG_NEWLINE)
nonnewline(p);
else
EMIT(OANY, 0);
break;
case '[':
p_bracket(p);
break;
case '\\':
REQUIRE(MORE(), REG_EESCAPE);
c = GETNEXT();
ordinary(p, c);
break;
case '{': /* okay as ordinary except if digit
* follows */
REQUIRE(!MORE() || !pg_isdigit(PEEK()), REG_BADRPT);
/* FALLTHROUGH */
default:
ordinary(p, c);
break;
}
if (!MORE())
return; return;
c = PEEK();
/* we call { a repetition if followed by a digit */
if (!(c == '*' || c == '+' || c == '?' ||
(c == '{' && MORE2() && pg_isdigit(PEEK2()))))
return; /* no repetition, we're done */
NEXT();
REQUIRE(!wascaret, REG_BADRPT);
switch (c)
{
case '*': /* implemented as +? */
/* this case does not require the (y|) trick, noKLUDGE */
INSERT(OPLUS_, pos);
ASTERN(O_PLUS, pos);
INSERT(OQUEST_, pos);
ASTERN(O_QUEST, pos);
break;
case '+':
INSERT(OPLUS_, pos);
ASTERN(O_PLUS, pos);
break;
case '?':
/* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
INSERT(OCH_, pos); /* offset slightly wrong */
ASTERN(OOR1, pos); /* this one's right */
AHEAD(pos); /* fix the OCH_ */
EMIT(OOR2, 0); /* offset very wrong... */
AHEAD(THERE()); /* ...so fix it */
ASTERN(O_CH, THERETHERE());
break;
case '{':
count = p_count(p);
if (EAT(','))
{
if (pg_isdigit(PEEK()))
{
count2 = p_count(p);
REQUIRE(count <= count2, REG_BADBR);
}
else
/* single number with comma */
count2 = INFINITY;
} }
else v->subs = p;
/* just a single number */ for (p = &v->subs[v->nsubs]; v->nsubs < n; p++, v->nsubs++)
count2 = count; *p = NULL;
repeat(p, pos, count, count2); assert(v->nsubs == n);
if (!EAT('}')) assert((size_t)wanted < v->nsubs);
{ /* error heuristics */
while (MORE() && PEEK() != '}')
NEXT();
REQUIRE(MORE(), REG_EBRACE);
SETERROR(REG_BADBR);
}
break;
}
if (!MORE())
return;
c = PEEK();
if (!(c == '*' || c == '+' || c == '?' ||
(c == '{' && MORE2() && pg_isdigit(PEEK2()))))
return;
SETERROR(REG_BADRPT);
} }
/* /*
* p_str - string (no metacharacters) "parser" * freev - free vars struct's substructures where necessary
*
* Optionally does error-number setting, and always returns error code
* (if any), to make error-handling code terser.
*/ */
static void static int
p_str(struct parse * p) freev(struct vars *v,
int err)
{ {
REQUIRE(MORE(), REG_EMPTY); if (v->re != NULL)
while (MORE()) rfree(v->re);
ordinary(p, GETNEXT()); if (v->subs != v->sub10)
FREE(v->subs);
if (v->nfa != NULL)
freenfa(v->nfa);
if (v->tree != NULL)
freesubre(v, v->tree);
if (v->treechain != NULL)
cleanst(v);
if (v->cv != NULL)
freecvec(v->cv);
if (v->cv2 != NULL)
freecvec(v->cv2);
if (v->mcces != NULL)
freecvec(v->mcces);
if (v->lacons != NULL)
freelacons(v->lacons, v->nlacons);
ERR(err); /* nop if err==0 */
return v->err;
} }
/* /*
* p_bre - BRE parser top level, anchoring and concatenation * makesearch - turn an NFA into a search NFA (implicit prepend of .*?)
* * NFA must have been optimize()d already.
* Giving end1 as OUT essentially eliminates the end1/end2 check.
*
* This implementation is a bit of a kludge, in that a trailing $ is first
* taken as an ordinary character and then revised to be an anchor. The
* only undesirable side effect is that '$' gets included as a character
* category in such cases. This is fairly harmless; not worth fixing.
* The amount of lookahead needed to avoid this kludge is excessive.
*/ */
static void static void
p_bre(struct parse * p, makesearch(struct vars *v,
int end1, /* first terminating character */ struct nfa *nfa)
int end2) /* second terminating character */
{ {
sopno start = HERE(); struct arc *a;
int first = 1; /* first subexpression? */ struct arc *b;
int wasdollar = 0; struct state *pre = nfa->pre;
struct state *s;
if (EAT('^')) struct state *s2;
{ struct state *slist;
EMIT(OBOL, 0);
p->g->iflags |= USEBOL; /* no loops are needed if it's anchored */
p->g->nbol++; for (a = pre->outs; a != NULL; a = a->outchain) {
} assert(a->type == PLAIN);
while (MORE() && !SEETWO(end1, end2)) if (a->co != nfa->bos[0] && a->co != nfa->bos[1])
{ break;
wasdollar = p_simp_re(p, first);
first = 0;
}
if (wasdollar)
{ /* oops, that was a trailing anchor */
DROP(1);
EMIT(OEOL, 0);
p->g->iflags |= USEEOL;
p->g->neol++;
} }
if (a != NULL) {
/* add implicit .* in front */
rainbow(nfa, v->cm, PLAIN, COLORLESS, pre, pre);
REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */ /* and ^* and \A* too -- not always necessary, but harmless */
} newarc(nfa, PLAIN, nfa->bos[0], pre, pre);
newarc(nfa, PLAIN, nfa->bos[1], pre, pre);
}
/* /*
* p_simp_re - parse a simple RE, an atom possibly followed by a repetition * Now here's the subtle part. Because many REs have no lookback
* constraints, often knowing when you were in the pre state tells
* you little; it's the next state(s) that are informative. But
* some of them may have other inarcs, i.e. it may be possible to
* make actual progress and then return to one of them. We must
* de-optimize such cases, splitting each such state into progress
* and no-progress states.
*/ */
static int /* was the simple RE an unbackslashed $? */
p_simp_re(struct parse * p,
int starordinary) /* is a leading * an ordinary character? */
{
int c;
int count;
int count2;
sopno pos;
int i;
sopno subno;
#define BACKSL (1<<24)
pos = HERE(); /* repetion op, if any, covers from here */ /* first, make a list of the states */
slist = NULL;
assert(MORE()); /* caller should have ensured this */ for (a = pre->outs; a != NULL; a = a->outchain) {
c = GETNEXT(); s = a->to;
if (c == '\\') for (b = s->ins; b != NULL; b = b->inchain)
{ if (b->from != pre)
REQUIRE(MORE(), REG_EESCAPE);
c = BACKSL | (pg_wchar) GETNEXT();
}
switch (c)
{
case '.':
if (p->g->cflags & REG_NEWLINE)
nonnewline(p);
else
EMIT(OANY, 0);
break; break;
case '[': if (b != NULL) { /* must be split */
p_bracket(p); s->tmp = slist;
break; slist = s;
case BACKSL | '{':
SETERROR(REG_BADRPT);
break;
case BACKSL | '(':
p->g->nsub++;
subno = p->g->nsub;
if (subno < NPAREN)
p->pbegin[subno] = HERE();
EMIT(OLPAREN, subno);
/* the MORE here is an error heuristic */
if (MORE() && !SEETWO('\\', ')'))
p_bre(p, '\\', ')');
if (subno < NPAREN)
{
p->pend[subno] = HERE();
assert(p->pend[subno] != 0);
} }
EMIT(ORPAREN, subno);
REQUIRE(EATTWO('\\', ')'), REG_EPAREN);
break;
case BACKSL | ')': /* should not get here -- must be user */
case BACKSL | '}':
SETERROR(REG_EPAREN);
break;
case BACKSL | '1':
case BACKSL | '2':
case BACKSL | '3':
case BACKSL | '4':
case BACKSL | '5':
case BACKSL | '6':
case BACKSL | '7':
case BACKSL | '8':
case BACKSL | '9':
i = (c & ~BACKSL) - '0';
assert(i < NPAREN);
if (p->pend[i] != 0)
{
assert(i <= p->g->nsub);
EMIT(OBACK_, i);
assert(p->pbegin[i] != 0);
assert(OP(p->strip[p->pbegin[i]]) == OLPAREN);
assert(OP(p->strip[p->pend[i]]) == ORPAREN);
dupl(p, p->pbegin[i] + 1, p->pend[i]);
EMIT(O_BACK, i);
}
else
SETERROR(REG_ESUBREG);
p->g->backrefs = 1;
break;
case '*':
REQUIRE(starordinary, REG_BADRPT);
/* FALLTHROUGH */
default:
ordinary(p, c & ~BACKSL);
break;
} }
if (EAT('*')) /* do the splits */
{ /* implemented as +? */ for (s = slist; s != NULL; s = s2) {
/* this case does not require the (y|) trick, noKLUDGE */ s2 = newstate(nfa);
INSERT(OPLUS_, pos); copyouts(nfa, s, s2);
ASTERN(O_PLUS, pos); for (a = s->ins; a != NULL; a = b) {
INSERT(OQUEST_, pos); b = a->inchain;
ASTERN(O_QUEST, pos); if (a->from != pre) {
} cparc(nfa, a, a->from, s2);
else if (EATTWO('\\', '{')) freearc(nfa, a);
{
count = p_count(p);
if (EAT(','))
{
if (MORE() && pg_isdigit(PEEK()))
{
count2 = p_count(p);
REQUIRE(count <= count2, REG_BADBR);
} }
else
/* single number with comma */
count2 = INFINITY;
} }
else s2 = s->tmp;
/* just a single number */ s->tmp = NULL; /* clean up while we're at it */
count2 = count;
repeat(p, pos, count, count2);
if (!EATTWO('\\', '}'))
{ /* error heuristics */
while (MORE() && !SEETWO('\\', '}'))
NEXT();
REQUIRE(MORE(), REG_EBRACE);
SETERROR(REG_BADBR);
} }
}
else if (c == (unsigned char) '$') /* $ (but not \$) ends it */
return 1;
return 0;
} }
/* /*
* p_count - parse a repetition count * parse - parse an RE
*
* This is actually just the top level, which parses a bunch of branches
* tied together with '|'. They appear in the tree as the left children
* of a chain of '|' subres.
*/ */
static int /* the value */ static struct subre *
p_count(struct parse * p) parse(struct vars *v,
int stopper, /* EOS or ')' */
int type, /* LACON (lookahead subRE) or PLAIN */
struct state *init, /* initial state */
struct state *final) /* final state */
{ {
int count = 0; struct state *left; /* scaffolding for branch */
int ndigits = 0; struct state *right;
struct subre *branches; /* top level */
struct subre *branch; /* current branch */
struct subre *t; /* temporary */
int firstbranch; /* is this the first branch? */
assert(stopper == ')' || stopper == EOS);
branches = subre(v, '|', LONGER, init, final);
NOERRN();
branch = branches;
firstbranch = 1;
do { /* a branch */
if (!firstbranch) {
/* need a place to hang it */
branch->right = subre(v, '|', LONGER, init, final);
NOERRN();
branch = branch->right;
}
firstbranch = 0;
left = newstate(v->nfa);
right = newstate(v->nfa);
NOERRN();
EMPTYARC(init, left);
EMPTYARC(right, final);
NOERRN();
branch->left = parsebranch(v, stopper, type, left, right, 0);
NOERRN();
branch->flags |= UP(branch->flags | branch->left->flags);
if ((branch->flags &~ branches->flags) != 0) /* new flags */
for (t = branches; t != branch; t = t->right)
t->flags |= branch->flags;
} while (EAT('|'));
assert(SEE(stopper) || SEE(EOS));
if (!SEE(stopper)) {
assert(stopper == ')' && SEE(EOS));
ERR(REG_EPAREN);
}
while (MORE() && pg_isdigit(PEEK()) && count <= DUPMAX) /* optimize out simple cases */
{ if (branch == branches) { /* only one branch */
count = count * 10 + (GETNEXT() - '0'); assert(branch->right == NULL);
ndigits++; t = branch->left;
branch->left = NULL;
freesubre(v, branches);
branches = t;
} else if (!MESSY(branches->flags)) { /* no interesting innards */
freesubre(v, branches->left);
branches->left = NULL;
freesubre(v, branches->right);
branches->right = NULL;
branches->op = '=';
} }
REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR); return branches;
return count;
} }
/* /*
* p_bracket - parse a bracketed character list * parsebranch - parse one branch of an RE
* *
* Note a significant property of this code: if the allocset() did SETERROR, * This mostly manages concatenation, working closely with parseqatom().
* no set operations are done. * Concatenated things are bundled up as much as possible, with separate
* ',' nodes introduced only when necessary due to substructure.
*/ */
static void static struct subre *
p_bracket(struct parse * p) parsebranch(struct vars *v,
int stopper, /* EOS or ')' */
int type, /* LACON (lookahead subRE) or PLAIN */
struct state *left, /* leftmost state */
struct state *right, /* rightmost state */
int partial) /* is this only part of a branch? */
{ {
cset *cs = allocset(p); struct state *lp; /* left end of current construct */
int invert = 0; int seencontent; /* is there anything in this branch yet? */
struct subre *t;
pg_wchar sp1[] = {'[', ':', '<', ':', ']', ']'};
pg_wchar sp2[] = {'[', ':', '>', ':', ']', ']'}; lp = left;
seencontent = 0;
/* Dept of Truly Sickening Special-Case Kludges */ t = subre(v, '=', 0, left, right); /* op '=' is tentative */
if (p->next + 5 < p->end && pg_wchar_strncmp(p->next, sp1, 6) == 0) NOERRN();
{ while (!SEE('|') && !SEE(stopper) && !SEE(EOS)) {
EMIT(OBOW, 0); if (seencontent) { /* implicit concat operator */
NEXTn(6); lp = newstate(v->nfa);
return; NOERRN();
} moveins(v->nfa, right, lp);
if (p->next + 5 < p->end && pg_wchar_strncmp(p->next, sp2, 6) == 0)
{
EMIT(OEOW, 0);
NEXTn(6);
return;
} }
seencontent = 1;
if (EAT('^')) /* NB, recursion in parseqatom() may swallow rest of branch */
invert++; /* make note to invert set at end */ parseqatom(v, stopper, type, lp, right, t);
if (EAT(']'))
CHadd(cs, ']');
else if (EAT('-'))
CHadd(cs, '-');
while (MORE() && PEEK() != ']' && !SEETWO('-', ']'))
p_b_term(p, cs);
if (EAT('-'))
CHadd(cs, '-');
MUSTEAT(']', REG_EBRACK);
if (p->error != 0) /* don't mess things up further */
return;
if (p->g->cflags & REG_ICASE)
{
int i;
int ci;
for (i = p->g->csetsize - 1; i >= 0; i--)
if (CHIN(cs, i) && pg_isalpha(i))
{
ci = othercase(i);
if (ci != i)
CHadd(cs, ci);
} }
if (cs->multis != NULL)
mccase(p, cs);
}
if (invert)
{
int i;
for (i = p->g->csetsize - 1; i >= 0; i--) if (!seencontent) { /* empty branch */
if (CHIN(cs, i)) if (!partial)
CHsub(cs, i); NOTE(REG_UUNSPEC);
else assert(lp == left);
CHadd(cs, i); EMPTYARC(left, right);
if (p->g->cflags & REG_NEWLINE)
CHsub(cs, '\n');
if (cs->multis != NULL)
mcinvert(p, cs);
} }
assert(cs->multis == NULL); /* xxx */ return t;
if (nch(p, cs) == 1)
{ /* optimize singleton sets */
ordinary(p, firstch(p, cs));
freeset(p, cs);
}
else
EMIT(OANYOF, freezeset(p, cs));
} }
/* /*
* p_b_term - parse one term of a bracketed character list * parseqatom - parse one quantified atom or constraint of an RE
*
* The bookkeeping near the end cooperates very closely with parsebranch();
* in particular, it contains a recursion that can involve parsing the rest
* of the branch, making this function's name somewhat inaccurate.
*/ */
static void static void
p_b_term(struct parse * p, cset *cs) parseqatom(struct vars *v,
int stopper, /* EOS or ')' */
int type, /* LACON (lookahead subRE) or PLAIN */
struct state *lp, /* left state to hang it on */
struct state *rp, /* right state to hang it on */
struct subre *top) /* subtree top */
{ {
pg_wchar c; struct state *s; /* temporaries for new states */
pg_wchar start, struct state *s2;
finish; # define ARCV(t, val) newarc(v->nfa, t, val, lp, rp)
int i; int m, n;
struct subre *atom; /* atom's subtree */
/* classify what we've got */ struct subre *t;
switch ((MORE()) ? PEEK() : '\0') int cap; /* capturing parens? */
{ int pos; /* positive lookahead? */
case '[': int subno; /* capturing-parens or backref number */
c = (MORE2()) ? PEEK2() : '\0'; int atomtype;
int qprefer; /* quantifier short/long preference */
int f;
struct subre **atomp; /* where the pointer to atom is */
/* initial bookkeeping */
atom = NULL;
assert(lp->nouts == 0); /* must string new code */
assert(rp->nins == 0); /* between lp and rp */
subno = 0; /* just to shut lint up */
/* an atom or constraint... */
atomtype = v->nexttype;
switch (atomtype) {
/* first, constraints, which end by returning */
case '^':
ARCV('^', 1);
if (v->cflags&REG_NLANCH)
ARCV(BEHIND, v->nlcolor);
NEXT();
return;
break;
case '$':
ARCV('$', 1);
if (v->cflags&REG_NLANCH)
ARCV(AHEAD, v->nlcolor);
NEXT();
return;
break; break;
case '-': case SBEGIN:
SETERROR(REG_ERANGE); ARCV('^', 1); /* BOL */
return; /* NOTE RETURN */ ARCV('^', 0); /* or BOS */
NEXT();
return;
break;
case SEND:
ARCV('$', 1); /* EOL */
ARCV('$', 0); /* or EOS */
NEXT();
return;
break;
case '<':
wordchrs(v); /* does NEXT() */
s = newstate(v->nfa);
NOERR();
nonword(v, BEHIND, lp, s);
word(v, AHEAD, s, rp);
return;
break;
case '>':
wordchrs(v); /* does NEXT() */
s = newstate(v->nfa);
NOERR();
word(v, BEHIND, lp, s);
nonword(v, AHEAD, s, rp);
return;
break;
case WBDRY:
wordchrs(v); /* does NEXT() */
s = newstate(v->nfa);
NOERR();
nonword(v, BEHIND, lp, s);
word(v, AHEAD, s, rp);
s = newstate(v->nfa);
NOERR();
word(v, BEHIND, lp, s);
nonword(v, AHEAD, s, rp);
return;
break;
case NWBDRY:
wordchrs(v); /* does NEXT() */
s = newstate(v->nfa);
NOERR();
word(v, BEHIND, lp, s);
word(v, AHEAD, s, rp);
s = newstate(v->nfa);
NOERR();
nonword(v, BEHIND, lp, s);
nonword(v, AHEAD, s, rp);
return;
break;
case LACON: /* lookahead constraint */
pos = v->nextvalue;
NEXT();
s = newstate(v->nfa);
s2 = newstate(v->nfa);
NOERR();
t = parse(v, ')', LACON, s, s2);
freesubre(v, t); /* internal structure irrelevant */
assert(SEE(')') || ISERR());
NEXT();
n = newlacon(v, s, s2, pos);
NOERR();
ARCV(LACON, n);
return;
break;
/* then errors, to get them out of the way */
case '*':
case '+':
case '?':
case '{':
ERR(REG_BADRPT);
return;
break; break;
default: default:
c = '\0'; ERR(REG_ASSERT);
return;
break; break;
/* then plain characters, and minor variants on that theme */
case ')': /* unbalanced paren */
if ((v->cflags&REG_ADVANCED) != REG_EXTENDED) {
ERR(REG_EPAREN);
return;
} }
/* legal in EREs due to specification botch */
switch (c) NOTE(REG_UPBOTCH);
{ /* fallthrough into case PLAIN */
case ':': /* character class */ case PLAIN:
NEXT2(); onechr(v, v->nextvalue, lp, rp);
REQUIRE(MORE(), REG_EBRACK); okcolors(v->nfa, v->cm);
c = PEEK(); NOERR();
REQUIRE(c != '-' && c != ']', REG_ECTYPE); NEXT();
p_b_cclass(p, cs);
REQUIRE(MORE(), REG_EBRACK);
REQUIRE(EATTWO(':', ']'), REG_ECTYPE);
break; break;
case '=': /* equivalence class */ case '[':
NEXT2(); if (v->nextvalue == 1)
REQUIRE(MORE(), REG_EBRACK); bracket(v, lp, rp);
c = PEEK(); else
REQUIRE(c != '-' && c != ']', REG_ECOLLATE); cbracket(v, lp, rp);
p_b_eclass(p, cs); assert(SEE(']') || ISERR());
REQUIRE(MORE(), REG_EBRACK); NEXT();
REQUIRE(EATTWO('=', ']'), REG_ECOLLATE);
break; break;
default: /* symbol, ordinary character, or range */ case '.':
/* xxx revision needed for multichar stuff */ rainbow(v->nfa, v->cm, PLAIN,
start = p_b_symbol(p); (v->cflags&REG_NLSTOP) ? v->nlcolor : COLORLESS,
if (SEE('-') && MORE2() && PEEK2() != ']') lp, rp);
{
/* range */
NEXT(); NEXT();
if (EAT('-')) break;
finish = '-'; /* and finally the ugly stuff */
else case '(': /* value flags as capturing or non */
finish = p_b_symbol(p); cap = (type == LACON) ? 0 : v->nextvalue;
if (cap) {
v->nsubexp++;
subno = v->nsubexp;
if ((size_t)subno >= v->nsubs)
moresubs(v, subno);
assert((size_t)subno < v->nsubs);
} else
atomtype = PLAIN; /* something that's not '(' */
NEXT();
/* need new endpoints because tree will contain pointers */
s = newstate(v->nfa);
s2 = newstate(v->nfa);
NOERR();
EMPTYARC(lp, s);
EMPTYARC(s2, rp);
NOERR();
atom = parse(v, ')', PLAIN, s, s2);
assert(SEE(')') || ISERR());
NEXT();
NOERR();
if (cap) {
v->subs[subno] = atom;
t = subre(v, '(', atom->flags|CAP, lp, rp);
NOERR();
t->subno = subno;
t->left = atom;
atom = t;
} }
else /* postpone everything else pending possible {0} */
finish = start; break;
/* xxx what about signed chars here... */ case BACKREF: /* the Feature From The Black Lagoon */
REQUIRE(start <= finish, REG_ERANGE); INSIST(type != LACON, REG_ESUBREG);
INSIST(v->nextvalue < v->nsubs, REG_ESUBREG);
if (CHlc(start) != CHlc(finish)) INSIST(v->subs[v->nextvalue] != NULL, REG_ESUBREG);
SETERROR(REG_ERANGE); NOERR();
assert(v->nextvalue > 0);
for (i = start; i <= finish; i++) atom = subre(v, 'b', BACKR, lp, rp);
CHadd(cs, i); subno = v->nextvalue;
atom->subno = subno;
EMPTYARC(lp, rp); /* temporarily, so there's something */
NEXT();
break; break;
} }
}
/* /* ...and an atom may be followed by a quantifier */
* p_b_cclass - parse a character-class name and deal with it switch (v->nexttype) {
*/ case '*':
static void m = 0;
p_b_cclass(struct parse * p, cset *cs) n = INFINITY;
{ qprefer = (v->nextvalue) ? LONGER : SHORTER;
pg_wchar *sp = p->next;
struct cclass *cp;
size_t len;
char *u;
unsigned char c;
while (MORE() && pg_isalpha(PEEK()))
NEXT(); NEXT();
len = p->next - sp;
for (cp = cclasses; cp->name != NULL; cp++)
if (pg_char_and_wchar_strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0')
break; break;
case '+':
if (cp->name == NULL) m = 1;
{ n = INFINITY;
/* oops, didn't find it */ qprefer = (v->nextvalue) ? LONGER : SHORTER;
SETERROR(REG_ECTYPE); NEXT();
break;
case '?':
m = 0;
n = 1;
qprefer = (v->nextvalue) ? LONGER : SHORTER;
NEXT();
break;
case '{':
NEXT();
m = scannum(v);
if (EAT(',')) {
if (SEE(DIGIT))
n = scannum(v);
else
n = INFINITY;
if (m > n) {
ERR(REG_BADBR);
return; return;
} }
/* {m,n} exercises preference, even if it's {m,m} */
qprefer = (v->nextvalue) ? LONGER : SHORTER;
} else {
n = m;
/* {m} passes operand's preference through */
qprefer = 0;
}
if (!SEE('}')) { /* catches errors too */
ERR(REG_BADBR);
return;
}
NEXT();
break;
default: /* no quantifier */
m = n = 1;
qprefer = 0;
break;
}
u = cp->chars; /* annoying special case: {0} or {0,0} cancels everything */
while ((c = *u++) != '\0') if (m == 0 && n == 0) {
CHadd(cs, c); if (atom != NULL)
for (u = cp->multis; *u != '\0'; u += strlen(u) + 1) freesubre(v, atom);
MCadd(p, cs, u); if (atomtype == '(')
} v->subs[subno] = NULL;
delsub(v->nfa, lp, rp);
/* EMPTYARC(lp, rp);
* p_b_eclass - parse an equivalence-class name and deal with it return;
* }
* This implementation is incomplete. xxx
*/
static void
p_b_eclass(struct parse * p, cset *cs)
{
char c;
c = p_b_coll_elem(p, '='); /* if not a messy case, avoid hard part */
CHadd(cs, c); assert(!MESSY(top->flags));
} f = top->flags | qprefer | ((atom != NULL) ? atom->flags : 0);
if (atomtype != '(' && atomtype != BACKREF && !MESSY(UP(f))) {
if (!(m == 1 && n == 1))
repeat(v, lp, rp, m, n);
if (atom != NULL)
freesubre(v, atom);
top->flags = f;
return;
}
/* /*
* p_b_symbol - parse a character or [..]ed multicharacter collating symbol * hard part: something messy
* That is, capturing parens, back reference, short/long clash, or
* an atom with substructure containing one of those.
*/ */
static pg_wchar /* value of symbol */
p_b_symbol(struct parse * p)
{
pg_wchar value;
REQUIRE(MORE(), REG_EBRACK);
if (!EATTWO('[', '.'))
return GETNEXT();
/* collating symbol */ /* now we'll need a subre for the contents even if they're boring */
value = p_b_coll_elem(p, '.'); if (atom == NULL) {
REQUIRE(EATTWO('.', ']'), REG_ECOLLATE); atom = subre(v, '=', 0, lp, rp);
return value; NOERR();
} }
/* /*
* p_b_coll_elem - parse a collating-element name and look it up * prepare a general-purpose state skeleton
*
* ---> [s] ---prefix---> [begin] ---atom---> [end] ----rest---> [rp]
* / /
* [lp] ----> [s2] ----bypass---------------------
*
* where bypass is an empty, and prefix is some repetitions of atom
*/ */
static char /* value of collating element */ s = newstate(v->nfa); /* first, new endpoints for the atom */
p_b_coll_elem(struct parse * p, int endc) s2 = newstate(v->nfa);
{ NOERR();
pg_wchar *sp = p->next; moveouts(v->nfa, lp, s);
struct cname *cp; moveins(v->nfa, rp, s2);
int len; NOERR();
atom->begin = s;
while (MORE() && !SEETWO(endc, ']')) atom->end = s2;
NEXT(); s = newstate(v->nfa); /* and spots for prefix and bypass */
if (!MORE()) s2 = newstate(v->nfa);
{ NOERR();
SETERROR(REG_EBRACK); EMPTYARC(lp, s);
return 0; EMPTYARC(lp, s2);
NOERR();
/* break remaining subRE into x{...} and what follows */
t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp);
t->left = atom;
atomp = &t->left;
/* here we should recurse... but we must postpone that to the end */
/* split top into prefix and remaining */
assert(top->op == '=' && top->left == NULL && top->right == NULL);
top->left = subre(v, '=', top->flags, top->begin, lp);
top->op = '.';
top->right = t;
/* if it's a backref, now is the time to replicate the subNFA */
if (atomtype == BACKREF) {
assert(atom->begin->nouts == 1); /* just the EMPTY */
delsub(v->nfa, atom->begin, atom->end);
assert(v->subs[subno] != NULL);
/* and here's why the recursion got postponed: it must */
/* wait until the skeleton is filled in, because it may */
/* hit a backref that wants to copy the filled-in skeleton */
dupnfa(v->nfa, v->subs[subno]->begin, v->subs[subno]->end,
atom->begin, atom->end);
NOERR();
}
/* it's quantifier time; first, turn x{0,...} into x{1,...}|empty */
if (m == 0) {
EMPTYARC(s2, atom->end); /* the bypass */
assert(PREF(qprefer) != 0);
f = COMBINE(qprefer, atom->flags);
t = subre(v, '|', f, lp, atom->end);
NOERR();
t->left = atom;
t->right = subre(v, '|', PREF(f), s2, atom->end);
NOERR();
t->right->left = subre(v, '=', 0, s2, atom->end);
NOERR();
*atomp = t;
atomp = &t->left;
m = 1;
} }
len = p->next - sp;
for (cp = cnames; cp->name != NULL; cp++) /* deal with the rest of the quantifier */
if (pg_char_and_wchar_strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') if (atomtype == BACKREF) {
return cp->code; /* known name */ /* special case: backrefs have internal quantifiers */
EMPTYARC(s, atom->begin); /* empty prefix */
/* just stuff everything into atom */
repeat(v, atom->begin, atom->end, m, n);
atom->min = (short)m;
atom->max = (short)n;
atom->flags |= COMBINE(qprefer, atom->flags);
} else if (m == 1 && n == 1) {
/* no/vacuous quantifier: done */
EMPTYARC(s, atom->begin); /* empty prefix */
} else {
/* turn x{m,n} into x{m-1,n-1}x, with capturing */
/* parens in only second x */
dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin);
assert(m >= 1 && m != INFINITY && n >= 1);
repeat(v, s, atom->begin, m-1, (n == INFINITY) ? n : n-1);
f = COMBINE(qprefer, atom->flags);
t = subre(v, '.', f, s, atom->end); /* prefix and atom */
NOERR();
t->left = subre(v, '=', PREF(f), s, atom->begin);
NOERR();
t->right = atom;
*atomp = t;
}
if (len == 1) /* and finally, look after that postponed recursion */
return *sp; /* single character */ t = top->right;
SETERROR(REG_ECOLLATE); /* neither */ if (!(SEE('|') || SEE(stopper) || SEE(EOS)))
return 0; t->right = parsebranch(v, stopper, type, atom->end, rp, 1);
else {
EMPTYARC(atom->end, rp);
t->right = subre(v, '=', 0, atom->end, rp);
}
assert(SEE('|') || SEE(stopper) || SEE(EOS));
t->flags |= COMBINE(t->flags, t->right->flags);
top->flags |= COMBINE(top->flags, t->flags);
} }
/* /*
* othercase - return the case counterpart of an alphabetic * nonword - generate arcs for non-word-character ahead or behind
*/ */
static unsigned char /* if no counterpart, return ch */ static void
othercase(int ch) nonword(struct vars *v,
int dir, /* AHEAD or BEHIND */
struct state *lp,
struct state *rp)
{ {
assert(pg_isalpha(ch)); int anchor = (dir == AHEAD) ? '$' : '^';
if (pg_isupper(ch))
return (unsigned char) tolower((unsigned char) ch); assert(dir == AHEAD || dir == BEHIND);
else if (pg_islower(ch)) newarc(v->nfa, anchor, 1, lp, rp);
return (unsigned char) toupper((unsigned char) ch); newarc(v->nfa, anchor, 0, lp, rp);
else colorcomplement(v->nfa, v->cm, dir, v->wordchrs, lp, rp);
/* peculiar, but could happen */ /* (no need for special attention to \n) */
return (unsigned char) ch;
} }
/* /*
* bothcases - emit a dualcase version of a two-case character * word - generate arcs for word character ahead or behind
*
* Boy, is this implementation ever a kludge...
*/ */
static void static void
bothcases(struct parse * p, int ch) word(struct vars *v,
int dir, /* AHEAD or BEHIND */
struct state *lp,
struct state *rp)
{ {
pg_wchar *oldnext = p->next; assert(dir == AHEAD || dir == BEHIND);
pg_wchar *oldend = p->end; cloneouts(v->nfa, v->wordchrs, lp, rp, dir);
pg_wchar bracket[3]; /* (no need for special attention to \n) */
assert(othercase(ch) != ch); /* p_bracket() would recurse */
p->next = bracket;
p->end = bracket + 2;
bracket[0] = ch;
bracket[1] = ']';
bracket[2] = '\0';
p_bracket(p);
assert(p->next == bracket + 2);
p->next = oldnext;
p->end = oldend;
} }
/* /*
* ordinary - emit an ordinary character * scannum - scan a number
*/ */
static void static int /* value, <= DUPMAX */
ordinary(struct parse * p, int ch) scannum(struct vars *v)
{ {
cat_t *cap = p->g->categories; int n = 0;
if ((p->g->cflags & REG_ICASE) && pg_isalpha(ch) && othercase(ch) != ch) while (SEE(DIGIT) && n < DUPMAX) {
bothcases(p, ch); n = n*10 + v->nextvalue;
else NEXT();
{ }
EMIT(OCHAR, (pg_wchar) ch); if (SEE(DIGIT) || n > DUPMAX) {
if (ch >= CHAR_MIN && ch <= CHAR_MAX && cap[ch] == 0) ERR(REG_BADBR);
cap[ch] = p->g->ncategories++; return 0;
} }
return n;
} }
/* /*
* nonnewline - emit REG_NEWLINE version of OANY * repeat - replicate subNFA for quantifiers
* *
* Boy, is this implementation ever a kludge... * The duplication sequences used here are chosen carefully so that any
* pointers starting out pointing into the subexpression end up pointing into
* the last occurrence. (Note that it may not be strung between the same
* left and right end states, however!) This used to be important for the
* subRE tree, although the important bits are now handled by the in-line
* code in parse(), and when this is called, it doesn't matter any more.
*/ */
static void static void
nonnewline(struct parse * p) repeat(struct vars *v,
struct state *lp,
struct state *rp,
int m,
int n)
{ {
pg_wchar *oldnext = p->next; # define SOME 2
pg_wchar *oldend = p->end; # define INF 3
pg_wchar bracket[4]; # define PAIR(x, y) ((x)*4 + (y))
# define REDUCE(x) ( ((x) == INFINITY) ? INF : (((x) > 1) ? SOME : (x)) )
p->next = bracket; const int rm = REDUCE(m);
p->end = bracket + 3; const int rn = REDUCE(n);
bracket[0] = '^'; struct state *s;
bracket[1] = '\n'; struct state *s2;
bracket[2] = ']';
bracket[3] = '\0'; switch (PAIR(rm, rn)) {
p_bracket(p); case PAIR(0, 0): /* empty string */
assert(p->next == bracket + 3); delsub(v->nfa, lp, rp);
p->next = oldnext; EMPTYARC(lp, rp);
p->end = oldend;
}
/*
* repeat - generate code for a bounded repetition, recursively if needed
*/
static void
repeat(struct parse * p,
sopno start, /* operand from here to end of strip */
int from, /* repeated from this number */
int to) /* to this number of times (maybe
* INFINITY) */
{
sopno finish = HERE();
#define N 2
#define INF 3
#define REP(f, t) ((f)*8 + (t))
#define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N)
sopno copy;
if (p->error != 0) /* head off possible runaway recursion */
return;
assert(from <= to);
switch (REP(MAP(from), MAP(to)))
{
case REP(0, 0): /* must be user doing this */
DROP(finish - start); /* drop the operand */
break; break;
case REP(0, 1): /* as x{1,1}? */ case PAIR(0, 1): /* do as x| */
case REP(0, N): /* as x{1,n}? */ EMPTYARC(lp, rp);
case REP(0, INF): /* as x{1,}? */
/* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
INSERT(OCH_, start); /* offset is wrong... */
repeat(p, start + 1, 1, to);
ASTERN(OOR1, start);
AHEAD(start); /* ... fix it */
EMIT(OOR2, 0);
AHEAD(THERE());
ASTERN(O_CH, THERETHERE());
break; break;
case REP(1, 1): /* trivial case */ case PAIR(0, SOME): /* do as x{1,n}| */
/* done */ repeat(v, lp, rp, 1, n);
NOERR();
EMPTYARC(lp, rp);
break; break;
case REP(1, N): /* as x?x{1,n-1} */ case PAIR(0, INF): /* loop x around */
/* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ s = newstate(v->nfa);
INSERT(OCH_, start); NOERR();
ASTERN(OOR1, start); moveouts(v->nfa, lp, s);
AHEAD(start); moveins(v->nfa, rp, s);
EMIT(OOR2, 0); /* offset very wrong... */ EMPTYARC(lp, s);
AHEAD(THERE()); /* ...so fix it */ EMPTYARC(s, rp);
ASTERN(O_CH, THERETHERE());
copy = dupl(p, start + 1, finish + 1);
assert(copy == finish + 4);
repeat(p, copy, 1, to - 1);
break; break;
case REP(1, INF): /* as x+ */ case PAIR(1, 1): /* no action required */
INSERT(OPLUS_, start);
ASTERN(O_PLUS, start);
break; break;
case REP(N, N): /* as xx{m-1,n-1} */ case PAIR(1, SOME): /* do as x{0,n-1}x = (x{1,n-1}|)x */
copy = dupl(p, start, finish); s = newstate(v->nfa);
repeat(p, copy, from - 1, to - 1); NOERR();
moveouts(v->nfa, lp, s);
dupnfa(v->nfa, s, rp, lp, s);
NOERR();
repeat(v, lp, s, 1, n-1);
NOERR();
EMPTYARC(lp, s);
break; break;
case REP(N, INF): /* as xx{n-1,INF} */ case PAIR(1, INF): /* add loopback arc */
copy = dupl(p, start, finish); s = newstate(v->nfa);
repeat(p, copy, from - 1, to); s2 = newstate(v->nfa);
NOERR();
moveouts(v->nfa, lp, s);
moveins(v->nfa, rp, s2);
EMPTYARC(lp, s);
EMPTYARC(s2, rp);
EMPTYARC(s2, s);
break; break;
default: /* "can't happen" */ case PAIR(SOME, SOME): /* do as x{m-1,n-1}x */
SETERROR(REG_ASSERT); /* just in case */ s = newstate(v->nfa);
NOERR();
moveouts(v->nfa, lp, s);
dupnfa(v->nfa, s, rp, lp, s);
NOERR();
repeat(v, lp, s, m-1, n-1);
break;
case PAIR(SOME, INF): /* do as x{m-1,}x */
s = newstate(v->nfa);
NOERR();
moveouts(v->nfa, lp, s);
dupnfa(v->nfa, s, rp, lp, s);
NOERR();
repeat(v, lp, s, m-1, n);
break;
default:
ERR(REG_ASSERT);
break; break;
} }
} }
/* /*
* seterr - set an error condition * bracket - handle non-complemented bracket expression
* Also called from cbracket for complemented bracket expressions.
*/ */
static int /* useless but makes type checking happy */ static void
seterr(struct parse * p, int e) bracket(struct vars *v,
struct state *lp,
struct state *rp)
{ {
if (p->error == 0) /* keep earliest error condition */ assert(SEE('['));
p->error = e; NEXT();
p->next = nuls; /* try to bring things to a halt */ while (!SEE(']') && !SEE(EOS))
p->end = nuls; brackpart(v, lp, rp);
return 0; /* make the return value well-defined */ assert(SEE(']') || ISERR());
okcolors(v->nfa, v->cm);
} }
/* /*
* allocset - allocate a set of characters for [] * cbracket - handle complemented bracket expression
* We do it by calling bracket() with dummy endpoints, and then complementing
* the result. The alternative would be to invoke rainbow(), and then delete
* arcs as the b.e. is seen... but that gets messy.
*/ */
static cset * static void
allocset(struct parse * p) cbracket(struct vars *v,
struct state *lp,
struct state *rp)
{ {
int no = p->g->ncsets++; struct state *left = newstate(v->nfa);
size_t nc; struct state *right = newstate(v->nfa);
size_t nbytes; struct state *s;
cset *cs; struct arc *a; /* arc from lp */
size_t css = (size_t) p->g->csetsize; struct arc *ba; /* arc from left, from bracket() */
struct arc *pa; /* MCCE-prototype arc */
color co;
chr *p;
int i; int i;
if (no >= p->ncsalloc) NOERR();
{ /* need another column of space */ bracket(v, left, right);
p->ncsalloc += CHAR_BIT; if (v->cflags&REG_NLSTOP)
nc = p->ncsalloc; newarc(v->nfa, PLAIN, v->nlcolor, left, right);
assert(nc % CHAR_BIT == 0); NOERR();
nbytes = nc / CHAR_BIT * css;
if (p->g->sets == NULL) assert(lp->nouts == 0); /* all outarcs will be ours */
p->g->sets = (cset *) malloc(nc * sizeof(cset));
else /* easy part of complementing */
p->g->sets = (cset *) realloc((char *) p->g->sets, colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp);
nc * sizeof(cset)); NOERR();
if (p->g->setbits == NULL) if (v->mcces == NULL) { /* no MCCEs -- we're done */
p->g->setbits = (uch *) malloc(nbytes); dropstate(v->nfa, left);
else assert(right->nins == 0);
{ freestate(v->nfa, right);
p->g->setbits = (uch *) realloc((char *) p->g->setbits, return;
nbytes);
/* xxx this isn't right if setbits is now NULL */
for (i = 0; i < no; i++)
p->g->sets[i].ptr = p->g->setbits + css * (i / CHAR_BIT);
}
if (p->g->sets != NULL && p->g->setbits != NULL)
memset((char *) p->g->setbits + (nbytes - css),
0, css);
else
{
no = 0;
SETERROR(REG_ESPACE);
/* caller's responsibility not to do set ops */
}
} }
assert(p->g->sets != NULL); /* xxx */ /* but complementing gets messy in the presence of MCCEs... */
cs = &p->g->sets[no]; NOTE(REG_ULOCALE);
cs->ptr = p->g->setbits + css * ((no) / CHAR_BIT); for (p = v->mcces->chrs, i = v->mcces->nchrs; i > 0; p++, i--) {
cs->mask = 1 << ((no) % CHAR_BIT); co = GETCOLOR(v->cm, *p);
cs->hash = 0; a = findarc(lp, PLAIN, co);
cs->smultis = 0; ba = findarc(left, PLAIN, co);
cs->multis = NULL; if (ba == NULL) {
assert(a != NULL);
freearc(v->nfa, a);
} else {
assert(a == NULL);
}
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
pa = findarc(v->mccepbegin, PLAIN, co);
assert(pa != NULL);
if (ba == NULL) { /* easy case, need all of them */
cloneouts(v->nfa, pa->to, s, rp, PLAIN);
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, pa->to, s, rp);
} else { /* must be selective */
if (findarc(ba->to, '$', 1) == NULL) {
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, pa->to,
s, rp);
}
for (pa = pa->to->outs; pa != NULL; pa = pa->outchain)
if (findarc(ba->to, PLAIN, pa->co) == NULL)
newarc(v->nfa, PLAIN, pa->co, s, rp);
if (s->nouts == 0) /* limit of selectivity: none */
dropstate(v->nfa, s); /* frees arc too */
}
NOERR();
}
return cs; delsub(v->nfa, left, right);
assert(left->nouts == 0);
freestate(v->nfa, left);
assert(right->nins == 0);
freestate(v->nfa, right);
} }
/* /*
* freeset - free a now-unused set * brackpart - handle one item (or range) within a bracket expression
*/ */
static void static void
freeset(struct parse * p, cset *cs) brackpart(struct vars *v,
struct state *lp,
struct state *rp)
{ {
int i; celt startc;
cset *top = &p->g->sets[p->g->ncsets]; celt endc;
size_t css = (size_t) p->g->csetsize; struct cvec *cv;
chr *startp;
chr *endp;
chr c[1];
/* parse something, get rid of special cases, take shortcuts */
switch (v->nexttype) {
case RANGE: /* a-b-c or other botch */
ERR(REG_ERANGE);
return;
break;
case PLAIN:
c[0] = v->nextvalue;
NEXT();
/* shortcut for ordinary chr (not range, not MCCE leader) */
if (!SEE(RANGE) && !ISCELEADER(v, c[0])) {
onechr(v, c[0], lp, rp);
return;
}
startc = element(v, c, c+1);
NOERR();
break;
case COLLEL:
startp = v->now;
endp = scanplain(v);
INSIST(startp < endp, REG_ECOLLATE);
NOERR();
startc = element(v, startp, endp);
NOERR();
break;
case ECLASS:
startp = v->now;
endp = scanplain(v);
INSIST(startp < endp, REG_ECOLLATE);
NOERR();
startc = element(v, startp, endp);
NOERR();
cv = eclass(v, startc, (v->cflags&REG_ICASE));
NOERR();
dovec(v, cv, lp, rp);
return;
break;
case CCLASS:
startp = v->now;
endp = scanplain(v);
INSIST(startp < endp, REG_ECTYPE);
NOERR();
cv = cclass(v, startp, endp, (v->cflags&REG_ICASE));
NOERR();
dovec(v, cv, lp, rp);
return;
break;
default:
ERR(REG_ASSERT);
return;
break;
}
if (SEE(RANGE)) {
NEXT();
switch (v->nexttype) {
case PLAIN:
case RANGE:
c[0] = v->nextvalue;
NEXT();
endc = element(v, c, c+1);
NOERR();
break;
case COLLEL:
startp = v->now;
endp = scanplain(v);
INSIST(startp < endp, REG_ECOLLATE);
NOERR();
endc = element(v, startp, endp);
NOERR();
break;
default:
ERR(REG_ERANGE);
return;
break;
}
} else
endc = startc;
for (i = 0; i < css; i++) /*
CHsub(cs, i); * Ranges are unportable. Actually, standard C does
if (cs == top - 1) /* recover only the easy case */ * guarantee that digits are contiguous, but making
p->g->ncsets--; * that an exception is just too complicated.
*/
if (startc != endc)
NOTE(REG_UUNPORT);
cv = range(v, startc, endc, (v->cflags&REG_ICASE));
NOERR();
dovec(v, cv, lp, rp);
} }
/* /*
* freezeset - final processing on a set of characters * scanplain - scan PLAIN contents of [. etc.
* *
* The main task here is merging identical sets. This is usually a waste * Certain bits of trickery in lex.c know that this code does not try
* of time (although the hash code minimizes the overhead), but can win * to look past the final bracket of the [. etc.
* big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash
* is done using addition rather than xor -- all ASCII [aA] sets xor to
* the same value!
*/ */
static int /* set number */ static chr * /* just after end of sequence */
freezeset(struct parse * p, cset *cs) scanplain(struct vars *v)
{ {
uch h = cs->hash; chr *endp;
int i;
cset *top = &p->g->sets[p->g->ncsets];
cset *cs2;
size_t css = (size_t) p->g->csetsize;
/* look for an earlier one which is the same */ assert(SEE(COLLEL) || SEE(ECLASS) || SEE(CCLASS));
for (cs2 = &p->g->sets[0]; cs2 < top; cs2++) NEXT();
if (cs2->hash == h && cs2 != cs)
{
/* maybe */
for (i = 0; i < css; i++)
if (!!CHIN(cs2, i) != !!CHIN(cs, i))
break; /* no */
if (i == css)
break; /* yes */
}
if (cs2 < top) endp = v->now;
{ /* found one */ while (SEE(PLAIN)) {
freeset(p, cs); endp = v->now;
cs = cs2; NEXT();
} }
return (int) (cs - p->g->sets); assert(SEE(END) || ISERR());
NEXT();
return endp;
} }
/* /*
* firstch - return first character in a set (which must have at least one) * leaders - process a cvec of collating elements to also include leaders
* Also gives all characters involved their own colors, which is almost
* certainly necessary, and sets up little disconnected subNFA.
*/ */
static int /* character; there is no "none" value */ static void
firstch(struct parse * p, cset *cs) leaders(struct vars *v,
struct cvec *cv)
{ {
int i; int mcce;
size_t css = (size_t) p->g->csetsize; chr *p;
chr leader;
for (i = 0; i < css; i++) struct state *s;
if (CHIN(cs, i)) struct arc *a;
return i;
assert(never); v->mccepbegin = newstate(v->nfa);
return 0; /* arbitrary */ v->mccepend = newstate(v->nfa);
NOERR();
for (mcce = 0; mcce < cv->nmcces; mcce++) {
p = cv->mcces[mcce];
leader = *p;
if (!haschr(cv, leader)) {
addchr(cv, leader);
s = newstate(v->nfa);
newarc(v->nfa, PLAIN, subcolor(v->cm, leader),
v->mccepbegin, s);
okcolors(v->nfa, v->cm);
} else {
a = findarc(v->mccepbegin, PLAIN,
GETCOLOR(v->cm, leader));
assert(a != NULL);
s = a->to;
assert(s != v->mccepend);
}
p++;
assert(*p != 0 && *(p+1) == 0); /* only 2-char MCCEs for now */
newarc(v->nfa, PLAIN, subcolor(v->cm, *p), s, v->mccepend);
okcolors(v->nfa, v->cm);
}
} }
/* /*
* nch - number of characters in a set * onechr - fill in arcs for a plain character, and possible case complements
* This is mostly a shortcut for efficient handling of the common case.
*/ */
static int static void
nch(struct parse * p, cset *cs) onechr(struct vars *v,
chr c,
struct state *lp,
struct state *rp)
{ {
int i; if (!(v->cflags&REG_ICASE)) {
size_t css = (size_t) p->g->csetsize; newarc(v->nfa, PLAIN, subcolor(v->cm, c), lp, rp);
int n = 0; return;
}
for (i = 0; i < css; i++) /* rats, need general case anyway... */
if (CHIN(cs, i)) dovec(v, allcases(v, c), lp, rp);
n++;
return n;
} }
/* /*
* mcadd - add a collating element to a cset * dovec - fill in arcs for each element of a cvec
* This one has to handle the messy cases, like MCCEs and MCCE leaders.
*/ */
static void static void
mcadd(struct parse * p, cset *cs, char *cp) dovec(struct vars *v,
struct cvec *cv,
struct state *lp,
struct state *rp)
{ {
size_t oldend = cs->smultis; chr ch, from, to;
celt ce;
chr *p;
int i;
color co;
struct cvec *leads;
struct arc *a;
struct arc *pa; /* arc in prototype */
struct state *s;
struct state *ps; /* state in prototype */
/* need a place to store leaders, if any */
if (nmcces(v) > 0) {
assert(v->mcces != NULL);
if (v->cv2 == NULL || v->cv2->nchrs < v->mcces->nchrs) {
if (v->cv2 != NULL)
free(v->cv2);
v->cv2 = newcvec(v->mcces->nchrs, 0, v->mcces->nmcces);
NOERR();
leads = v->cv2;
} else
leads = clearcvec(v->cv2);
} else
leads = NULL;
/* first, get the ordinary characters out of the way */
for (p = cv->chrs, i = cv->nchrs; i > 0; p++, i--) {
ch = *p;
if (!ISCELEADER(v, ch))
newarc(v->nfa, PLAIN, subcolor(v->cm, ch), lp, rp);
else {
assert(singleton(v->cm, ch));
assert(leads != NULL);
if (!haschr(leads, ch))
addchr(leads, ch);
}
}
cs->smultis += strlen(cp) + 1; /* and the ranges */
if (cs->multis == NULL) for (p = cv->ranges, i = cv->nranges; i > 0; p += 2, i--) {
cs->multis = malloc(cs->smultis); from = *p;
else to = *(p+1);
cs->multis = realloc(cs->multis, cs->smultis); while (from <= to && (ce = nextleader(v, from, to)) != NOCELT) {
if (cs->multis == NULL) if (from < ce)
{ subrange(v, from, ce - 1, lp, rp);
SETERROR(REG_ESPACE); assert(singleton(v->cm, ce));
assert(leads != NULL);
if (!haschr(leads, ce))
addchr(leads, ce);
from = ce + 1;
}
if (from <= to)
subrange(v, from, to, lp, rp);
}
if ((leads == NULL || leads->nchrs == 0) && cv->nmcces == 0)
return; return;
/* deal with the MCCE leaders */
NOTE(REG_ULOCALE);
for (p = leads->chrs, i = leads->nchrs; i > 0; p++, i--) {
co = GETCOLOR(v->cm, *p);
a = findarc(lp, PLAIN, co);
if (a != NULL)
s = a->to;
else {
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
}
pa = findarc(v->mccepbegin, PLAIN, co);
assert(pa != NULL);
ps = pa->to;
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, ps, s, rp);
NOERR();
} }
strcpy(cs->multis + oldend - 1, cp); /* and the MCCEs */
cs->multis[cs->smultis - 1] = '\0'; for (i = 0; i < cv->nmcces; i++) {
p = cv->mcces[i];
assert(singleton(v->cm, *p));
if (!singleton(v->cm, *p)) {
ERR(REG_ASSERT);
return;
}
ch = *p++;
co = GETCOLOR(v->cm, ch);
a = findarc(lp, PLAIN, co);
if (a != NULL)
s = a->to;
else {
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
}
assert(*p != 0); /* at least two chars */
assert(singleton(v->cm, *p));
ch = *p++;
co = GETCOLOR(v->cm, ch);
assert(*p == 0); /* and only two, for now */
newarc(v->nfa, PLAIN, co, s, rp);
NOERR();
}
} }
/* /*
* mcinvert - invert the list of collating elements in a cset * nextleader - find next MCCE leader within range
*
* This would have to know the set of possibilities. Implementation
* is deferred.
*/ */
static void static celt /* NOCELT means none */
mcinvert(struct parse * p, cset *cs) nextleader(struct vars *v,
chr from,
chr to)
{ {
assert(cs->multis == NULL); /* xxx */ int i;
chr *p;
chr ch;
celt it = NOCELT;
if (v->mcces == NULL)
return it;
for (i = v->mcces->nchrs, p = v->mcces->chrs; i > 0; i--, p++) {
ch = *p;
if (from <= ch && ch <= to)
if (it == NOCELT || ch < it)
it = ch;
}
return it;
} }
/* /*
* mccase - add case counterparts of the list of collating elements in a cset * wordchrs - set up word-chr list for word-boundary stuff, if needed
* *
* This would have to know the set of possibilities. Implementation * The list is kept as a bunch of arcs between two dummy states; it's
* is deferred. * disposed of by the unreachable-states sweep in NFA optimization.
* Does NEXT(). Must not be called from any unusual lexical context.
* This should be reconciled with the \w etc. handling in lex.c, and
* should be cleaned up to reduce dependencies on input scanning.
*/ */
static void static void
mccase(struct parse * p, cset *cs) wordchrs(struct vars *v)
{ {
assert(cs->multis == NULL); /* xxx */ struct state *left;
} struct state *right;
/* if (v->wordchrs != NULL) {
* isinsets - is this character in any sets? NEXT(); /* for consistency */
*/ return;
static int /* predicate */ }
isinsets(struct re_guts * g, int c)
{
uch *col;
int i;
int ncols = (g->ncsets + (CHAR_BIT - 1)) / CHAR_BIT;
unsigned uc = (unsigned char) c;
for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) left = newstate(v->nfa);
if (col[uc] != 0) right = newstate(v->nfa);
return 1; NOERR();
return 0; /* fine point: implemented with [::], and lexer will set REG_ULOCALE */
lexword(v);
NEXT();
assert(v->savenow != NULL && SEE('['));
bracket(v, left, right);
assert((v->savenow != NULL && SEE(']')) || ISERR());
NEXT();
NOERR();
v->wordchrs = left;
} }
/* /*
* samesets - are these two characters in exactly the same sets? * subre - allocate a subre
*/ */
static int /* predicate */ static struct subre *
samesets(struct re_guts * g, int c1, int c2) subre(struct vars *v,
int op,
int flags,
struct state *begin,
struct state *end)
{ {
uch *col; struct subre *ret;
int i;
int ncols = (g->ncsets + (CHAR_BIT - 1)) / CHAR_BIT; ret = v->treefree;
unsigned uc1 = (unsigned char) c1; if (ret != NULL)
unsigned uc2 = (unsigned char) c2; v->treefree = ret->left;
else {
ret = (struct subre *)MALLOC(sizeof(struct subre));
if (ret == NULL) {
ERR(REG_ESPACE);
return NULL;
}
ret->chain = v->treechain;
v->treechain = ret;
}
for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) assert(strchr("|.b(=", op) != NULL);
if (col[uc1] != col[uc2])
return 0; ret->op = op;
return 1; ret->flags = flags;
ret->retry = 0;
ret->subno = 0;
ret->min = ret->max = 1;
ret->left = NULL;
ret->right = NULL;
ret->begin = begin;
ret->end = end;
ZAPCNFA(ret->cnfa);
return ret;
} }
/* /*
* categorize - sort out character categories * freesubre - free a subRE subtree
*/ */
static void static void
categorize(struct parse * p, struct re_guts * g) freesubre(struct vars *v, /* might be NULL */
struct subre *sr)
{ {
cat_t *cats = g->categories; if (sr == NULL)
int c;
int c2;
cat_t cat;
/* avoid making error situations worse */
if (p->error != 0)
return; return;
for (c = CHAR_MIN; c <= CHAR_MAX; c++) if (sr->left != NULL)
if (cats[c] == 0 && isinsets(g, c)) freesubre(v, sr->left);
{ if (sr->right != NULL)
cat = g->ncategories++; freesubre(v, sr->right);
cats[c] = cat;
for (c2 = c + 1; c2 <= CHAR_MAX; c2++) freesrnode(v, sr);
if (cats[c2] == 0 && samesets(g, c, c2))
cats[c2] = cat;
}
} }
/* /*
* dupl - emit a duplicate of a bunch of sops * freesrnode - free one node in a subRE subtree
*/ */
static sopno /* start of duplicate */ static void
dupl(struct parse * p, freesrnode(struct vars *v, /* might be NULL */
sopno start, /* from here */ struct subre *sr)
sopno finish) /* to this less one */
{ {
sopno ret = HERE(); if (sr == NULL)
sopno len = finish - start; return;
assert(finish >= start); if (!NULLCNFA(sr->cnfa))
if (len == 0) freecnfa(&sr->cnfa);
return ret; sr->flags = 0;
enlarge(p, p->ssize + len); /* this many unexpected additions */
assert(p->ssize >= p->slen + len); if (v != NULL) {
memcpy((char *) (p->strip + p->slen), sr->left = v->treefree;
(char *) (p->strip + start), (size_t) len * sizeof(sop)); v->treefree = sr;
p->slen += len; } else
return ret; FREE(sr);
} }
/* /*
* doemit - emit a strip operator * optst - optimize a subRE subtree
*
* It might seem better to implement this as a macro with a function as
* hard-case backup, but it's just too big and messy unless there are
* some changes to the data structures. Maybe later.
*/ */
static void static void
doemit(struct parse * p, sop op, size_t opnd) optst(struct vars *v,
struct subre *t)
{ {
/* avoid making error situations worse */ if (t == NULL)
if (p->error != 0)
return; return;
/* deal with oversize operands ("can't happen", more or less) */ /* recurse through children */
assert(opnd < 1 << OPSHIFT); if (t->left != NULL)
optst(v, t->left);
/* deal with undersized strip */ if (t->right != NULL)
if (p->slen >= p->ssize) optst(v, t->right);
enlarge(p, (p->ssize + 1) / 2 * 3); /* +50% */
assert(p->slen < p->ssize);
/* finally, it's all reduced to the easy case */
p->strip[p->slen++] = SOP(op, opnd);
} }
/* /*
* doinsert - insert a sop into the strip * numst - number tree nodes (assigning retry indexes)
*/ */
static void static int /* next number */
doinsert(struct parse * p, sop op, size_t opnd, sopno pos) numst(struct subre *t,
int start) /* starting point for subtree numbers */
{ {
sopno sn;
sop s;
int i; int i;
/* avoid making error situations worse */ assert(t != NULL);
if (p->error != 0)
return;
sn = HERE();
EMIT(op, opnd); /* do checks, ensure space */
assert(HERE() == sn + 1);
s = p->strip[sn];
/* adjust paren pointers */
assert(pos > 0);
for (i = 1; i < NPAREN; i++)
{
if (p->pbegin[i] >= pos)
p->pbegin[i]++;
if (p->pend[i] >= pos)
p->pend[i]++;
}
memmove((char *) &p->strip[pos + 1], (char *) &p->strip[pos], i = start;
(HERE() - pos - 1) * sizeof(sop)); t->retry = (short)i++;
p->strip[pos] = s; if (t->left != NULL)
i = numst(t->left, i);
if (t->right != NULL)
i = numst(t->right, i);
return i;
} }
/* /*
* dofwd - complete a forward reference * markst - mark tree nodes as INUSE
*/ */
static void static void
dofwd(struct parse * p, sopno pos, sop value) markst(struct subre *t)
{ {
/* avoid making error situations worse */ assert(t != NULL);
if (p->error != 0)
return;
assert(value < 1 << OPSHIFT); t->flags |= INUSE;
p->strip[pos] = OP(p->strip[pos]) | value; if (t->left != NULL)
markst(t->left);
if (t->right != NULL)
markst(t->right);
} }
/* /*
* enlarge - enlarge the strip * cleanst - free any tree nodes not marked INUSE
*/ */
static void static void
enlarge(struct parse * p, sopno size) cleanst(struct vars *v)
{ {
sop *sp; struct subre *t;
struct subre *next;
if (p->ssize >= size)
return;
sp = (sop *) realloc(p->strip, size * sizeof(sop)); for (t = v->treechain; t != NULL; t = next) {
if (sp == NULL) next = t->chain;
{ if (!(t->flags&INUSE))
SETERROR(REG_ESPACE); FREE(t);
return;
} }
p->strip = sp; v->treechain = NULL;
p->ssize = size; v->treefree = NULL; /* just on general principles */
} }
/* /*
* stripsnug - compact the strip * nfatree - turn a subRE subtree into a tree of compacted NFAs
*/ */
static void static long /* optimize results from top node */
stripsnug(struct parse * p, struct re_guts * g) nfatree(struct vars *v,
struct subre *t,
FILE *f) /* for debug output */
{ {
g->nstates = p->slen; assert(t != NULL && t->begin != NULL);
g->strip = (sop *) realloc((char *) p->strip, p->slen * sizeof(sop));
if (g->strip == NULL) if (t->left != NULL)
{ (DISCARD)nfatree(v, t->left, f);
SETERROR(REG_ESPACE); if (t->right != NULL)
g->strip = p->strip; (DISCARD)nfatree(v, t->right, f);
}
return nfanode(v, t, f);
} }
/* /*
* findmust - fill in must and mlen with longest mandatory literal string * nfanode - do one NFA for nfatree
*
* This algorithm could do fancy things like analyzing the operands of |
* for common subsequences. Someday. This code is simple and finds most
* of the interesting cases.
*
* Note that must and mlen got initialized during setup.
*/ */
static void static long /* optimize results */
findmust(struct parse * p, struct re_guts * g) nfanode(struct vars *v,
struct subre *t,
FILE *f) /* for debug output */
{ {
sop *scan; struct nfa *nfa;
sop *start = 0; long ret = 0;
sop *newstart = 0;
sopno newlen;
sop s;
pg_wchar *cp;
sopno i;
/* avoid making error situations worse */
if (p->error != 0)
return;
/* find the longest OCHAR sequence in strip */ assert(t->begin != NULL);
newlen = 0;
scan = g->strip + 1; #ifdef REG_DEBUG
do if (f != NULL)
{
s = *scan++;
switch (OP(s))
{
case OCHAR: /* sequence member */
if (newlen == 0) /* new sequence */
newstart = scan - 1;
newlen++;
break;
case OPLUS_: /* things that don't break one */
case OLPAREN:
case ORPAREN:
break;
case OQUEST_: /* things that must be skipped */
case OCH_:
scan--;
do
{
scan += OPND(s);
s = *scan;
/* assert() interferes w debug printouts */
if (OP(s) != O_QUEST && OP(s) != O_CH &&
OP(s) != OOR2)
{ {
g->iflags |= BAD; char idbuf[50];
return;
} fprintf(f, "\n\n\n========= TREE NODE %s ==========\n",
} while (OP(s) != O_QUEST && OP(s) != O_CH); stid(t, idbuf, sizeof(idbuf)));
/* fallthrough */
default: /* things that break a sequence */
if (newlen > g->mlen)
{ /* ends one */
start = newstart;
g->mlen = newlen;
} }
newlen = 0; #endif
break; nfa = newnfa(v, v->cm, v->nfa);
NOERRZ();
dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final);
if (!ISERR()) {
specialcolors(nfa);
ret = optimize(nfa, f);
} }
} while (OP(s) != OEND); if (!ISERR())
compact(nfa, &t->cnfa);
if (g->mlen == 0) /* there isn't one */ freenfa(nfa);
return; return ret;
}
/* turn it into a character string */ /*
g->must = (pg_wchar *) malloc((size_t) (g->mlen + 1) * sizeof(pg_wchar)); * newlacon - allocate a lookahead-constraint subRE
if (g->must == NULL) */
{ /* argh; just forget it */ static int /* lacon number */
g->mlen = 0; newlacon(struct vars *v,
return; struct state *begin,
struct state *end,
int pos)
{
int n;
struct subre *sub;
if (v->nlacons == 0) {
v->lacons = (struct subre *)MALLOC(2 * sizeof(struct subre));
n = 1; /* skip 0th */
v->nlacons = 2;
} else {
v->lacons = (struct subre *)REALLOC(v->lacons,
(v->nlacons+1)*sizeof(struct subre));
n = v->nlacons++;
} }
cp = g->must; if (v->lacons == NULL) {
scan = start; ERR(REG_ESPACE);
for (i = g->mlen; i > 0; i--) return 0;
{
while (OP(s = *scan++) != OCHAR)
continue;
assert(cp < g->must + g->mlen);
*cp++ = (pg_wchar) OPND(s);
} }
assert(cp == g->must + g->mlen); sub = &v->lacons[n];
*cp++ = '\0'; /* just on general principles */ sub->begin = begin;
sub->end = end;
sub->subno = pos;
ZAPCNFA(sub->cnfa);
return n;
} }
/* /*
* pluscount - count + nesting * freelacons - free lookahead-constraint subRE vector
*/ */
static sopno /* nesting depth */ static void
pluscount(struct parse * p, struct re_guts * g) freelacons(struct subre *subs,
int n)
{ {
sop *scan; struct subre *sub;
sop s; int i;
sopno plusnest = 0;
sopno maxnest = 0;
if (p->error != 0)
return 0; /* there may not be an OEND */
scan = g->strip + 1; assert(n > 0);
do for (sub = subs + 1, i = n - 1; i > 0; sub++, i--) /* no 0th */
{ if (!NULLCNFA(sub->cnfa))
s = *scan++; freecnfa(&sub->cnfa);
switch (OP(s)) FREE(subs);
{
case OPLUS_:
plusnest++;
break;
case O_PLUS:
if (plusnest > maxnest)
maxnest = plusnest;
plusnest--;
break;
}
} while (OP(s) != OEND);
if (plusnest != 0)
g->iflags |= BAD;
return maxnest;
} }
/* /*
* some ctype functions with non-ascii-char guard * rfree - free a whole RE (insides of regfree)
*/ */
static int static void
pg_isdigit(int c) rfree(regex_t *re)
{ {
return (c >= 0 && c <= UCHAR_MAX && isdigit((unsigned char) c)); struct guts *g;
}
static int if (re == NULL || re->re_magic != REMAGIC)
pg_isalpha(int c) return;
{
return (c >= 0 && c <= UCHAR_MAX && isalpha((unsigned char) c));
}
static int re->re_magic = 0; /* invalidate RE */
pg_isalnum(int c) g = (struct guts *)re->re_guts;
{ re->re_guts = NULL;
return (c >= 0 && c <= UCHAR_MAX && isalnum((unsigned char) c)); re->re_fns = NULL;
g->magic = 0;
freecm(&g->cmap);
if (g->tree != NULL)
freesubre((struct vars *)NULL, g->tree);
if (g->lacons != NULL)
freelacons(g->lacons, g->nlacons);
if (!NULLCNFA(g->search))
freecnfa(&g->search);
FREE(g);
} }
static int #ifdef REG_DEBUG
pg_isupper(int c)
{
return (c >= 0 && c <= UCHAR_MAX && isupper((unsigned char) c));
}
static int /*
pg_islower(int c) * dump - dump an RE in human-readable form
*/
static void
dump(regex_t *re,
FILE *f)
{ {
return (c >= 0 && c <= UCHAR_MAX && islower((unsigned char) c)); struct guts *g;
} int i;
static int if (re->re_magic != REMAGIC)
pg_iscntrl(int c) fprintf(f, "bad magic number (0x%x not 0x%x)\n", re->re_magic,
{ REMAGIC);
return (c >= 0 && c <= UCHAR_MAX && iscntrl((unsigned char) c)); if (re->re_guts == NULL) {
fprintf(f, "NULL guts!!!\n");
return;
}
g = (struct guts *)re->re_guts;
if (g->magic != GUTSMAGIC)
fprintf(f, "bad guts magic number (0x%x not 0x%x)\n", g->magic,
GUTSMAGIC);
fprintf(f, "\n\n\n========= DUMP ==========\n");
fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n",
re->re_nsub, re->re_info, re->re_csize, g->ntree);
dumpcolors(&g->cmap, f);
if (!NULLCNFA(g->search)) {
printf("\nsearch:\n");
dumpcnfa(&g->search, f);
}
for (i = 1; i < g->nlacons; i++) {
fprintf(f, "\nla%d (%s):\n", i,
(g->lacons[i].subno) ? "positive" : "negative");
dumpcnfa(&g->lacons[i].cnfa, f);
}
fprintf(f, "\n");
dumpst(g->tree, f, 0);
} }
static int /*
pg_isgraph(int c) * dumpst - dump a subRE tree
*/
static void
dumpst(struct subre *t,
FILE *f,
int nfapresent) /* is the original NFA still around? */
{ {
return (c >= 0 && c <= UCHAR_MAX && isgraph((unsigned char) c)); if (t == NULL)
fprintf(f, "null tree\n");
else
stdump(t, f, nfapresent);
fflush(f);
} }
static int /*
pg_isprint(int c) * stdump - recursive guts of dumpst
*/
static void
stdump(struct subre *t,
FILE *f,
int nfapresent) /* is the original NFA still around? */
{ {
return (c >= 0 && c <= UCHAR_MAX && isprint((unsigned char) c)); char idbuf[50];
fprintf(f, "%s. `%c'", stid(t, idbuf, sizeof(idbuf)), t->op);
if (t->flags&LONGER)
fprintf(f, " longest");
if (t->flags&SHORTER)
fprintf(f, " shortest");
if (t->flags&MIXED)
fprintf(f, " hasmixed");
if (t->flags&CAP)
fprintf(f, " hascapture");
if (t->flags&BACKR)
fprintf(f, " hasbackref");
if (!(t->flags&INUSE))
fprintf(f, " UNUSED");
if (t->subno != 0)
fprintf(f, " (#%d)", t->subno);
if (t->min != 1 || t->max != 1) {
fprintf(f, " {%d,", t->min);
if (t->max != INFINITY)
fprintf(f, "%d", t->max);
fprintf(f, "}");
}
if (nfapresent)
fprintf(f, " %ld-%ld", (long)t->begin->no, (long)t->end->no);
if (t->left != NULL)
fprintf(f, " L:%s", stid(t->left, idbuf, sizeof(idbuf)));
if (t->right != NULL)
fprintf(f, " R:%s", stid(t->right, idbuf, sizeof(idbuf)));
if (!NULLCNFA(t->cnfa)) {
fprintf(f, "\n");
dumpcnfa(&t->cnfa, f);
fprintf(f, "\n");
}
if (t->left != NULL)
stdump(t->left, f, nfapresent);
if (t->right != NULL)
stdump(t->right, f, nfapresent);
} }
static int /*
pg_ispunct(int c) * stid - identify a subtree node for dumping
*/
static char * /* points to buf or constant string */
stid(struct subre *t,
char *buf,
size_t bufsize)
{ {
return (c >= 0 && c <= UCHAR_MAX && ispunct((unsigned char) c)); /* big enough for hex int or decimal t->retry? */
if (bufsize < sizeof(int)*2 + 3 || bufsize < sizeof(t->retry)*3 + 1)
return "unable";
if (t->retry != 0)
sprintf(buf, "%d", t->retry);
else
sprintf(buf, "0x%x", (int)t); /* may lose bits, that's okay */
return buf;
} }
static struct cclass * #endif /* REG_DEBUG */
cclass_init(void)
{
static struct cclass cclasses_C[] = {
{"alnum", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", ""},
{"alpha", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", ""},
{"blank", " \t", ""},
{"cntrl", "\007\b\t\n\v\f\r\1\2\3\4\5\6\16\17\20\21\22\23\24\25\26\27\30\31\32\33\34\35\36\37\177", ""},
{"digit", "0123456789", ""},
{"graph", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", ""},
{"lower", "abcdefghijklmnopqrstuvwxyz", ""},
{"print", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~ ", ""},
{"punct", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", ""},
{"space", "\t\n\v\f\r ", ""},
{"upper", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", ""},
{"xdigit", "0123456789ABCDEFabcdef", ""},
{NULL, NULL, ""}
};
struct cclass *cp = NULL;
struct cclass *classes = NULL;
struct cclass_factory
{
char *name;
int (*func) (int);
char *chars;
} cclass_factories[] =
{
{
"alnum", pg_isalnum, NULL
},
{
"alpha", pg_isalpha, NULL
},
{
"blank", NULL, " \t"
},
{
"cntrl", pg_iscntrl, NULL
},
{
"digit", NULL, "0123456789"
},
{
"graph", pg_isgraph, NULL
},
{
"lower", pg_islower, NULL
},
{
"print", pg_isprint, NULL
},
{
"punct", pg_ispunct, NULL
},
{
"space", NULL, "\t\n\v\f\r "
},
{
"upper", pg_isupper, NULL
},
{
"xdigit", NULL, "0123456789ABCDEFabcdef"
},
{
NULL, NULL, NULL
}
};
struct cclass_factory *cf = NULL;
if (strcmp(setlocale(LC_CTYPE, NULL), "C") == 0)
return cclasses_C;
classes = malloc(sizeof(struct cclass) * (sizeof(cclass_factories) / sizeof(struct cclass_factory)));
if (classes == NULL)
elog(ERROR, "cclass_init: out of memory");
cp = classes;
for (cf = cclass_factories; cf->name != NULL; cf++)
{
cp->name = strdup(cf->name);
if (cf->chars)
cp->chars = strdup(cf->chars);
else
{
int x = 0,
y = 0;
cp->chars = malloc(sizeof(char) * 256);
if (cp->chars == NULL)
elog(ERROR, "cclass_init: out of memory");
for (x = 0; x < 256; x++)
{
if ((cf->func) (x))
*(cp->chars + y++) = x;
}
*(cp->chars + y) = '\0';
}
cp->multis = "";
cp++;
}
cp->name = cp->chars = NULL;
cp->multis = "";
return classes; #include "regc_lex.c"
} #include "regc_color.c"
#include "regc_nfa.c"
#include "regc_cvec.c"
#include "regc_locale.c"
src/backend/regex/rege_dfa.c 0 → 100644
View file @ 7bcc6d98
/*
* DFA routines
* This file is #included by regexec.c.
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Header: /cvsroot/pgsql/src/backend/regex/rege_dfa.c,v 1.1 2003/02/05 17:41:33 tgl Exp $
*
*/
/*
* longest - longest-preferred matching engine
*/
static chr * /* endpoint, or NULL */
longest(struct vars *v, /* used only for debug and exec flags */
struct dfa *d,
chr *start, /* where the match should start */
chr *stop, /* match must end at or before here */
int *hitstopp) /* record whether hit v->stop, if non-NULL */
{
chr *cp;
chr *realstop = (stop == v->stop) ? stop : stop + 1;
color co;
struct sset *css;
struct sset *ss;
chr *post;
int i;
struct colormap *cm = d->cm;
/* initialize */
css = initialize(v, d, start);
cp = start;
if (hitstopp != NULL)
*hitstopp = 0;
/* startup */
FDEBUG(("+++ startup +++\n"));
if (cp == v->start) {
co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
FDEBUG(("color %ld\n", (long)co));
} else {
co = GETCOLOR(cm, *(cp - 1));
FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
}
css = miss(v, d, css, co, cp, start);
if (css == NULL)
return NULL;
css->lastseen = cp;
/* main loop */
if (v->eflags&REG_FTRACE)
while (cp < realstop) {
FDEBUG(("+++ at c%d +++\n", css - d->ssets));
co = GETCOLOR(cm, *cp);
FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
ss = css->outs[co];
if (ss == NULL) {
ss = miss(v, d, css, co, cp+1, start);
if (ss == NULL)
break; /* NOTE BREAK OUT */
}
cp++;
ss->lastseen = cp;
css = ss;
}
else
while (cp < realstop) {
co = GETCOLOR(cm, *cp);
ss = css->outs[co];
if (ss == NULL) {
ss = miss(v, d, css, co, cp+1, start);
if (ss == NULL)
break; /* NOTE BREAK OUT */
}
cp++;
ss->lastseen = cp;
css = ss;
}
/* shutdown */
FDEBUG(("+++ shutdown at c%d +++\n", css - d->ssets));
if (cp == v->stop && stop == v->stop) {
if (hitstopp != NULL)
*hitstopp = 1;
co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
FDEBUG(("color %ld\n", (long)co));
ss = miss(v, d, css, co, cp, start);
/* special case: match ended at eol? */
if (ss != NULL && (ss->flags&POSTSTATE))
return cp;
else if (ss != NULL)
ss->lastseen = cp; /* to be tidy */
}
/* find last match, if any */
post = d->lastpost;
for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
if ((ss->flags&POSTSTATE) && post != ss->lastseen &&
(post == NULL || post < ss->lastseen))
post = ss->lastseen;
if (post != NULL) /* found one */
return post - 1;
return NULL;
}
/*
* shortest - shortest-preferred matching engine
*/
static chr * /* endpoint, or NULL */
shortest(struct vars *v,
struct dfa *d,
chr *start, /* where the match should start */
chr *min, /* match must end at or after here */
chr *max, /* match must end at or before here */
chr **coldp, /* store coldstart pointer here, if nonNULL */
int *hitstopp) /* record whether hit v->stop, if non-NULL */
{
chr *cp;
chr *realmin = (min == v->stop) ? min : min + 1;
chr *realmax = (max == v->stop) ? max : max + 1;
color co;
struct sset *css;
struct sset *ss;
struct colormap *cm = d->cm;
/* initialize */
css = initialize(v, d, start);
cp = start;
if (hitstopp != NULL)
*hitstopp = 0;
/* startup */
FDEBUG(("--- startup ---\n"));
if (cp == v->start) {
co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
FDEBUG(("color %ld\n", (long)co));
} else {
co = GETCOLOR(cm, *(cp - 1));
FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
}
css = miss(v, d, css, co, cp, start);
if (css == NULL)
return NULL;
css->lastseen = cp;
ss = css;
/* main loop */
if (v->eflags&REG_FTRACE)
while (cp < realmax) {
FDEBUG(("--- at c%d ---\n", css - d->ssets));
co = GETCOLOR(cm, *cp);
FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
ss = css->outs[co];
if (ss == NULL) {
ss = miss(v, d, css, co, cp+1, start);
if (ss == NULL)
break; /* NOTE BREAK OUT */
}
cp++;
ss->lastseen = cp;
css = ss;
if ((ss->flags&POSTSTATE) && cp >= realmin)
break; /* NOTE BREAK OUT */
}
else
while (cp < realmax) {
co = GETCOLOR(cm, *cp);
ss = css->outs[co];
if (ss == NULL) {
ss = miss(v, d, css, co, cp+1, start);
if (ss == NULL)
break; /* NOTE BREAK OUT */
}
cp++;
ss->lastseen = cp;
css = ss;
if ((ss->flags&POSTSTATE) && cp >= realmin)
break; /* NOTE BREAK OUT */
}
if (ss == NULL)
return NULL;
if (coldp != NULL) /* report last no-progress state set, if any */
*coldp = lastcold(v, d);
if ((ss->flags&POSTSTATE) && cp > min) {
assert(cp >= realmin);
cp--;
} else if (cp == v->stop && max == v->stop) {
co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
FDEBUG(("color %ld\n", (long)co));
ss = miss(v, d, css, co, cp, start);
/* match might have ended at eol */
if ((ss == NULL || !(ss->flags&POSTSTATE)) && hitstopp != NULL)
*hitstopp = 1;
}
if (ss == NULL || !(ss->flags&POSTSTATE))
return NULL;
return cp;
}
/*
* lastcold - determine last point at which no progress had been made
*/
static chr * /* endpoint, or NULL */
lastcold(struct vars *v,
struct dfa *d)
{
struct sset *ss;
chr *nopr;
int i;
nopr = d->lastnopr;
if (nopr == NULL)
nopr = v->start;
for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
if ((ss->flags&NOPROGRESS) && nopr < ss->lastseen)
nopr = ss->lastseen;
return nopr;
}
/*
* newdfa - set up a fresh DFA
*/
static struct dfa *
newdfa(struct vars *v,
struct cnfa *cnfa,
struct colormap *cm,
struct smalldfa *small) /* preallocated space, may be NULL */
{
struct dfa *d;
size_t nss = cnfa->nstates * 2;
int wordsper = (cnfa->nstates + UBITS - 1) / UBITS;
struct smalldfa *smallwas = small;
assert(cnfa != NULL && cnfa->nstates != 0);
if (nss <= FEWSTATES && cnfa->ncolors <= FEWCOLORS) {
assert(wordsper == 1);
if (small == NULL) {
small = (struct smalldfa *)MALLOC(
sizeof(struct smalldfa));
if (small == NULL) {
ERR(REG_ESPACE);
return NULL;
}
}
d = &small->dfa;
d->ssets = small->ssets;
d->statesarea = small->statesarea;
d->work = &d->statesarea[nss];
d->outsarea = small->outsarea;
d->incarea = small->incarea;
d->cptsmalloced = 0;
d->mallocarea = (smallwas == NULL) ? (char *)small : NULL;
} else {
d = (struct dfa *)MALLOC(sizeof(struct dfa));
if (d == NULL) {
ERR(REG_ESPACE);
return NULL;
}
d->ssets = (struct sset *)MALLOC(nss * sizeof(struct sset));
d->statesarea = (unsigned *)MALLOC((nss+WORK) * wordsper *
sizeof(unsigned));
d->work = &d->statesarea[nss * wordsper];
d->outsarea = (struct sset **)MALLOC(nss * cnfa->ncolors *
sizeof(struct sset *));
d->incarea = (struct arcp *)MALLOC(nss * cnfa->ncolors *
sizeof(struct arcp));
d->cptsmalloced = 1;
d->mallocarea = (char *)d;
if (d->ssets == NULL || d->statesarea == NULL ||
d->outsarea == NULL || d->incarea == NULL) {
freedfa(d);
ERR(REG_ESPACE);
return NULL;
}
}
d->nssets = (v->eflags&REG_SMALL) ? 7 : nss;
d->nssused = 0;
d->nstates = cnfa->nstates;
d->ncolors = cnfa->ncolors;
d->wordsper = wordsper;
d->cnfa = cnfa;
d->cm = cm;
d->lastpost = NULL;
d->lastnopr = NULL;
d->search = d->ssets;
/* initialization of sset fields is done as needed */
return d;
}
/*
* freedfa - free a DFA
*/
static void
freedfa(struct dfa *d)
{
if (d->cptsmalloced) {
if (d->ssets != NULL)
FREE(d->ssets);
if (d->statesarea != NULL)
FREE(d->statesarea);
if (d->outsarea != NULL)
FREE(d->outsarea);
if (d->incarea != NULL)
FREE(d->incarea);
}
if (d->mallocarea != NULL)
FREE(d->mallocarea);
}
/*
* hash - construct a hash code for a bitvector
*
* There are probably better ways, but they're more expensive.
*/
static unsigned
hash(unsigned *uv,
int n)
{
int i;
unsigned h;
h = 0;
for (i = 0; i < n; i++)
h ^= uv[i];
return h;
}
/*
* initialize - hand-craft a cache entry for startup, otherwise get ready
*/
static struct sset *
initialize(struct vars *v, /* used only for debug flags */
struct dfa *d,
chr *start)
{
struct sset *ss;
int i;
/* is previous one still there? */
if (d->nssused > 0 && (d->ssets[0].flags&STARTER))
ss = &d->ssets[0];
else { /* no, must (re)build it */
ss = getvacant(v, d, start, start);
for (i = 0; i < d->wordsper; i++)
ss->states[i] = 0;
BSET(ss->states, d->cnfa->pre);
ss->hash = HASH(ss->states, d->wordsper);
assert(d->cnfa->pre != d->cnfa->post);
ss->flags = STARTER|LOCKED|NOPROGRESS;
/* lastseen dealt with below */
}
for (i = 0; i < d->nssused; i++)
d->ssets[i].lastseen = NULL;
ss->lastseen = start; /* maybe untrue, but harmless */
d->lastpost = NULL;
d->lastnopr = NULL;
return ss;
}
/*
* miss - handle a cache miss
*/
static struct sset * /* NULL if goes to empty set */
miss(struct vars *v, /* used only for debug flags */
struct dfa *d,
struct sset *css,
pcolor co,
chr *cp, /* next chr */
chr *start) /* where the attempt got started */
{
struct cnfa *cnfa = d->cnfa;
int i;
unsigned h;
struct carc *ca;
struct sset *p;
int ispost;
int noprogress;
int gotstate;
int dolacons;
int sawlacons;
/* for convenience, we can be called even if it might not be a miss */
if (css->outs[co] != NULL) {
FDEBUG(("hit\n"));
return css->outs[co];
}
FDEBUG(("miss\n"));
/* first, what set of states would we end up in? */
for (i = 0; i < d->wordsper; i++)
d->work[i] = 0;
ispost = 0;
noprogress = 1;
gotstate = 0;
for (i = 0; i < d->nstates; i++)
if (ISBSET(css->states, i))
for (ca = cnfa->states[i]+1; ca->co != COLORLESS; ca++)
if (ca->co == co) {
BSET(d->work, ca->to);
gotstate = 1;
if (ca->to == cnfa->post)
ispost = 1;
if (!cnfa->states[ca->to]->co)
noprogress = 0;
FDEBUG(("%d -> %d\n", i, ca->to));
}
dolacons = (gotstate) ? (cnfa->flags&HASLACONS) : 0;
sawlacons = 0;
while (dolacons) { /* transitive closure */
dolacons = 0;
for (i = 0; i < d->nstates; i++)
if (ISBSET(d->work, i))
for (ca = cnfa->states[i]+1; ca->co != COLORLESS;
ca++) {
if (ca->co <= cnfa->ncolors)
continue; /* NOTE CONTINUE */
sawlacons = 1;
if (ISBSET(d->work, ca->to))
continue; /* NOTE CONTINUE */
if (!lacon(v, cnfa, cp, ca->co))
continue; /* NOTE CONTINUE */
BSET(d->work, ca->to);
dolacons = 1;
if (ca->to == cnfa->post)
ispost = 1;
if (!cnfa->states[ca->to]->co)
noprogress = 0;
FDEBUG(("%d :> %d\n", i, ca->to));
}
}
if (!gotstate)
return NULL;
h = HASH(d->work, d->wordsper);
/* next, is that in the cache? */
for (p = d->ssets, i = d->nssused; i > 0; p++, i--)
if (HIT(h, d->work, p, d->wordsper)) {
FDEBUG(("cached c%d\n", p - d->ssets));
break; /* NOTE BREAK OUT */
}
if (i == 0) { /* nope, need a new cache entry */
p = getvacant(v, d, cp, start);
assert(p != css);
for (i = 0; i < d->wordsper; i++)
p->states[i] = d->work[i];
p->hash = h;
p->flags = (ispost) ? POSTSTATE : 0;
if (noprogress)
p->flags |= NOPROGRESS;
/* lastseen to be dealt with by caller */
}
if (!sawlacons) { /* lookahead conds. always cache miss */
FDEBUG(("c%d[%d]->c%d\n", css - d->ssets, co, p - d->ssets));
css->outs[co] = p;
css->inchain[co] = p->ins;
p->ins.ss = css;
p->ins.co = (color)co;
}
return p;
}
/*
* lacon - lookahead-constraint checker for miss()
*/
static int /* predicate: constraint satisfied? */
lacon(struct vars *v,
struct cnfa *pcnfa, /* parent cnfa */
chr *cp,
pcolor co) /* "color" of the lookahead constraint */
{
int n;
struct subre *sub;
struct dfa *d;
struct smalldfa sd;
chr *end;
n = co - pcnfa->ncolors;
assert(n < v->g->nlacons && v->g->lacons != NULL);
FDEBUG(("=== testing lacon %d\n", n));
sub = &v->g->lacons[n];
d = newdfa(v, &sub->cnfa, &v->g->cmap, &sd);
if (d == NULL) {
ERR(REG_ESPACE);
return 0;
}
end = longest(v, d, cp, v->stop, (int *)NULL);
freedfa(d);
FDEBUG(("=== lacon %d match %d\n", n, (end != NULL)));
return (sub->subno) ? (end != NULL) : (end == NULL);
}
/*
* getvacant - get a vacant state set
* This routine clears out the inarcs and outarcs, but does not otherwise
* clear the innards of the state set -- that's up to the caller.
*/
static struct sset *
getvacant(struct vars *v, /* used only for debug flags */
struct dfa *d,
chr *cp,
chr *start)
{
int i;
struct sset *ss;
struct sset *p;
struct arcp ap;
struct arcp lastap;
color co;
ss = pickss(v, d, cp, start);
assert(!(ss->flags&LOCKED));
/* clear out its inarcs, including self-referential ones */
ap = ss->ins;
while ((p = ap.ss) != NULL) {
co = ap.co;
FDEBUG(("zapping c%d's %ld outarc\n", p - d->ssets, (long)co));
p->outs[co] = NULL;
ap = p->inchain[co];
p->inchain[co].ss = NULL; /* paranoia */
}
ss->ins.ss = NULL;
/* take it off the inarc chains of the ssets reached by its outarcs */
for (i = 0; i < d->ncolors; i++) {
p = ss->outs[i];
assert(p != ss); /* not self-referential */
if (p == NULL)
continue; /* NOTE CONTINUE */
FDEBUG(("del outarc %d from c%d's in chn\n", i, p - d->ssets));
if (p->ins.ss == ss && p->ins.co == i)
p->ins = ss->inchain[i];
else {
assert(p->ins.ss != NULL);
for (ap = p->ins; ap.ss != NULL &&
!(ap.ss == ss && ap.co == i);
ap = ap.ss->inchain[ap.co])
lastap = ap;
assert(ap.ss != NULL);
lastap.ss->inchain[lastap.co] = ss->inchain[i];
}
ss->outs[i] = NULL;
ss->inchain[i].ss = NULL;
}
/* if ss was a success state, may need to remember location */
if ((ss->flags&POSTSTATE) && ss->lastseen != d->lastpost &&
(d->lastpost == NULL || d->lastpost < ss->lastseen))
d->lastpost = ss->lastseen;
/* likewise for a no-progress state */
if ((ss->flags&NOPROGRESS) && ss->lastseen != d->lastnopr &&
(d->lastnopr == NULL || d->lastnopr < ss->lastseen))
d->lastnopr = ss->lastseen;
return ss;
}
/*
* pickss - pick the next stateset to be used
*/
static struct sset *
pickss(struct vars *v, /* used only for debug flags */
struct dfa *d,
chr *cp,
chr *start)
{
int i;
struct sset *ss;
struct sset *end;
chr *ancient;
/* shortcut for cases where cache isn't full */
if (d->nssused < d->nssets) {
i = d->nssused;
d->nssused++;
ss = &d->ssets[i];
FDEBUG(("new c%d\n", i));
/* set up innards */
ss->states = &d->statesarea[i * d->wordsper];
ss->flags = 0;
ss->ins.ss = NULL;
ss->ins.co = WHITE; /* give it some value */
ss->outs = &d->outsarea[i * d->ncolors];
ss->inchain = &d->incarea[i * d->ncolors];
for (i = 0; i < d->ncolors; i++) {
ss->outs[i] = NULL;
ss->inchain[i].ss = NULL;
}
return ss;
}
/* look for oldest, or old enough anyway */
if (cp - start > d->nssets*2/3) /* oldest 33% are expendable */
ancient = cp - d->nssets*2/3;
else
ancient = start;
for (ss = d->search, end = &d->ssets[d->nssets]; ss < end; ss++)
if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
!(ss->flags&LOCKED)) {
d->search = ss + 1;
FDEBUG(("replacing c%d\n", ss - d->ssets));
return ss;
}
for (ss = d->ssets, end = d->search; ss < end; ss++)
if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
!(ss->flags&LOCKED)) {
d->search = ss + 1;
FDEBUG(("replacing c%d\n", ss - d->ssets));
return ss;
}
/* nobody's old enough?!? -- something's really wrong */
FDEBUG(("can't find victim to replace!\n"));
assert(NOTREACHED);
ERR(REG_ASSERT);
return d->ssets;
}
src/backend/regex/regerror.c
View file @ 7bcc6d98
/*- /*
* Copyright (c) 1992, 1993, 1994 Henry Spencer. * regerror - error-code expansion
* Copyright (c) 1992, 1993, 1994 *
* The Regents of the University of California. All rights reserved. * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
* *
* This code is derived from software contributed to Berkeley by * I'd appreciate being given credit for this package in the documentation
* Henry Spencer. * of software which uses it, but that is not a requirement.
* *
* Redistribution and use in source and binary forms, with or without * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* modification, are permitted provided that the following conditions * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* are met: * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* 1. Redistributions of source code must retain the above copyright * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* notice, this list of conditions and the following disclaimer. * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* 2. Redistributions in binary form must reproduce the above copyright * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* notice, this list of conditions and the following disclaimer in the * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* documentation and/or other materials provided with the distribution. * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* 3. All advertising materials mentioning features or use of this software * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* must display the following acknowledgement: * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * $Header: /cvsroot/pgsql/src/backend/regex/regerror.c,v 1.25 2003/02/05 17:41:33 tgl Exp $
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* *
* @(#)regerror.c 8.4 (Berkeley) 3/20/94
*/ */
#include "postgres.h" #include "regex/regguts.h"
#include <ctype.h> /* unknown-error explanation */
#include <limits.h> static char unk[] = "*** unknown regex error code 0x%x ***";
#include <assert.h>
#include "regex/regex.h" /* struct to map among codes, code names, and explanations */
#include "regex/utils.h" static struct rerr {
#include "regex/regex2.h"
static char *regatoi(const regex_t *preg, char *localbuf);
static struct rerr
{
int code; int code;
char *name; char *name;
char *explain; char *explain;
} rerrs[] = } rerrs[] = {
/* the actual table is built from regex.h */
{ #include "regex/regerrs.h"
{ { -1, "", "oops" }, /* explanation special-cased in code */
/* NOMATCH is not really an error condition, it just says no match */
REG_NOMATCH, "REG_NOMATCH", "no pattern match found"
},
{
REG_BADPAT, "REG_BADPAT", "invalid regex struct"
},
{
REG_ECOLLATE, "REG_ECOLLATE", "invalid collating element"
},
{
REG_ECTYPE, "REG_ECTYPE", "invalid character class"
},
{
REG_EESCAPE, "REG_EESCAPE", "trailing backslash (\\)"
},
{
REG_ESUBREG, "REG_ESUBREG", "invalid backreference number"
},
{
REG_EBRACK, "REG_EBRACK", "brackets [ ] not balanced"
},
{
REG_EPAREN, "REG_EPAREN", "parentheses ( ) not balanced"
},
{
REG_EBRACE, "REG_EBRACE", "braces { } not balanced"
},
{
REG_BADBR, "REG_BADBR", "invalid repetition count(s) in { }"
},
{
REG_ERANGE, "REG_ERANGE", "invalid character range in [ ]"
},
{
REG_ESPACE, "REG_ESPACE", "ran out of memory"
},
{
REG_BADRPT, "REG_BADRPT", "?, *, or + operand invalid"
},
{
REG_EMPTY, "REG_EMPTY", "empty expression or subexpression"
},
{
REG_ASSERT, "REG_ASSERT", "\"can't happen\" -- you found a bug"
},
{
REG_INVARG, "REG_INVARG", "invalid argument to regex routine"
},
{
0, "", "*** unknown regexp error code ***"
}
}; };
/* /*
* regerror - the interface to error numbers * pg_regerror - the interface to error numbers
*/ */
/* ARGSUSED */ /* ARGSUSED */
size_t size_t /* actual space needed (including NUL) */
pg_regerror(int errcode, const regex_t *preg, pg_regerror(int errcode, /* error code, or REG_ATOI or REG_ITOA */
char *errbuf, size_t errbuf_size) const regex_t *preg, /* associated regex_t (unused at present) */
char *errbuf, /* result buffer (unless errbuf_size==0) */
size_t errbuf_size) /* available space in errbuf, can be 0 */
{ {
struct rerr *r; struct rerr *r;
char *msg;
char convbuf[sizeof(unk)+50]; /* 50 = plenty for int */
size_t len; size_t len;
int target = errcode & ~REG_ITOA; int icode;
char *s;
char convbuf[50];
if (errcode == REG_ATOI) switch (errcode) {
s = regatoi(preg, convbuf); case REG_ATOI: /* convert name to number */
else for (r = rerrs; r->code >= 0; r++)
{ if (strcmp(r->name, errbuf) == 0)
for (r = rerrs; r->code != 0; r++)
if (r->code == target)
break; break;
sprintf(convbuf, "%d", r->code); /* -1 for unknown */
if (errcode & REG_ITOA) msg = convbuf;
{ break;
if (r->code != 0) case REG_ITOA: /* convert number to name */
strcpy(convbuf, r->name); icode = atoi(errbuf); /* not our problem if this fails */
else for (r = rerrs; r->code >= 0; r++)
sprintf(convbuf, "REG_0x%x", target); if (r->code == icode)
assert(strlen(convbuf) < sizeof(convbuf)); break;
s = convbuf; if (r->code >= 0)
msg = r->name;
else { /* unknown; tell him the number */
sprintf(convbuf, "REG_%u", (unsigned)icode);
msg = convbuf;
} }
else break;
s = r->explain; default: /* a real, normal error code */
for (r = rerrs; r->code >= 0; r++)
if (r->code == errcode)
break;
if (r->code >= 0)
msg = r->explain;
else { /* unknown; say so */
sprintf(convbuf, unk, errcode);
msg = convbuf;
}
break;
} }
len = strlen(s) + 1; len = strlen(msg) + 1; /* space needed, including NUL */
if (errbuf_size > 0) if (errbuf_size > 0) {
{
if (errbuf_size > len) if (errbuf_size > len)
strcpy(errbuf, s); strcpy(errbuf, msg);
else else { /* truncate to fit */
{ strncpy(errbuf, msg, errbuf_size-1);
strncpy(errbuf, s, errbuf_size - 1); errbuf[errbuf_size-1] = '\0';
errbuf[errbuf_size - 1] = '\0';
} }
} }
return len; return len;
} }
/*
* regatoi - internal routine to implement REG_ATOI
*/
static char *
regatoi(const regex_t *preg, char *localbuf)
{
struct rerr *r;
for (r = rerrs; r->code != 0; r++)
if (pg_char_and_wchar_strcmp(r->name, preg->re_endp) == 0)
break;
if (r->code == 0)
return "0";
sprintf(localbuf, "%d", r->code);
return localbuf;
}
src/backend/regex/regex.3 deleted 100644 → 0
View file @ 32c3db0f
.\" Copyright (c) 1992, 1993, 1994 Henry Spencer.
.\" Copyright (c) 1992, 1993, 1994
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" Henry Spencer.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" @(#)regex.3 8.4 (Berkeley) 3/20/94
.\"
.TH REGEX 3 "March 20, 1994"
.de ZR
.\" one other place knows this name: the SEE ALSO section
.IR re_format (7) \\$1
..
.SH NAME
regcomp, regexec, regerror, regfree \- regular-expression library
.SH SYNOPSIS
.ft B
.\".na
#include <sys/types.h>
.br
#include <regex.h>
.HP 10
int regcomp(regex_t\ *preg, const\ char\ *pattern, int\ cflags);
.HP
int\ regexec(const\ regex_t\ *preg, const\ char\ *string,
size_t\ nmatch, regmatch_t\ pmatch[], int\ eflags);
.HP
size_t\ regerror(int\ errcode, const\ regex_t\ *preg,
char\ *errbuf, size_t\ errbuf_size);
.HP
void\ regfree(regex_t\ *preg);
.\".ad
.ft
.SH DESCRIPTION
These routines implement POSIX 1003.2 regular expressions (``RE''s);
see
.ZR .
.I Regcomp
compiles an RE written as a string into an internal form,
.I regexec
matches that internal form against a string and reports results,
.I regerror
transforms error codes from either into human-readable messages,
and
.I regfree
frees any dynamically-allocated storage used by the internal form
of an RE.
.PP
The header
.I <regex.h>
declares two structure types,
.I regex_t
and
.IR regmatch_t ,
the former for compiled internal forms and the latter for match reporting.
It also declares the four functions,
a type
.IR regoff_t ,
and a number of constants with names starting with ``REG_''.
.PP
.I Regcomp
compiles the regular expression contained in the
.I pattern
string,
subject to the flags in
.IR cflags ,
and places the results in the
.I regex_t
structure pointed to by
.IR preg .
.I Cflags
is the bitwise OR of zero or more of the following flags:
.IP REG_EXTENDED \w'REG_EXTENDED'u+2n
Compile modern (``extended'') REs,
rather than the obsolete (``basic'') REs that
are the default.
.IP REG_BASIC
This is a synonym for 0,
provided as a counterpart to REG_EXTENDED to improve readability.
.IP REG_NOSPEC
Compile with recognition of all special characters turned off.
All characters are thus considered ordinary,
so the ``RE'' is a literal string.
This is an extension,
compatible with but not specified by POSIX 1003.2,
and should be used with
caution in software intended to be portable to other systems.
REG_EXTENDED and REG_NOSPEC may not be used
in the same call to
.IR regcomp .
.IP REG_ICASE
Compile for matching that ignores upper/lower case distinctions.
See
.ZR .
.IP REG_NOSUB
Compile for matching that need only report success or failure,
not what was matched.
.IP REG_NEWLINE
Compile for newline-sensitive matching.
By default, newline is a completely ordinary character with no special
meaning in either REs or strings.
With this flag,
`[^' bracket expressions and `.' never match newline,
a `^' anchor matches the null string after any newline in the string
in addition to its normal function,
and the `$' anchor matches the null string before any newline in the
string in addition to its normal function.
.IP REG_PEND
The regular expression ends,
not at the first NUL,
but just before the character pointed to by the
.I re_endp
member of the structure pointed to by
.IR preg .
The
.I re_endp
member is of type
.IR const\ char\ * .
This flag permits inclusion of NULs in the RE;
they are considered ordinary characters.
This is an extension,
compatible with but not specified by POSIX 1003.2,
and should be used with
caution in software intended to be portable to other systems.
.PP
When successful,
.I regcomp
returns 0 and fills in the structure pointed to by
.IR preg .
One member of that structure
(other than
.IR re_endp )
is publicized:
.IR re_nsub ,
of type
.IR size_t ,
contains the number of parenthesized subexpressions within the RE
(except that the value of this member is undefined if the
REG_NOSUB flag was used).
If
.I regcomp
fails, it returns a non-zero error code;
see DIAGNOSTICS.
.PP
.I Regexec
matches the compiled RE pointed to by
.I preg
against the
.IR string ,
subject to the flags in
.IR eflags ,
and reports results using
.IR nmatch ,
.IR pmatch ,
and the returned value.
The RE must have been compiled by a previous invocation of
.IR regcomp .
The compiled form is not altered during execution of
.IR regexec ,
so a single compiled RE can be used simultaneously by multiple threads.
.PP
By default,
the NUL-terminated string pointed to by
.I string
is considered to be the text of an entire line, minus any terminating
newline.
The
.I eflags
argument is the bitwise OR of zero or more of the following flags:
.IP REG_NOTBOL \w'REG_STARTEND'u+2n
The first character of
the string
is not the beginning of a line, so the `^' anchor should not match before it.
This does not affect the behavior of newlines under REG_NEWLINE.
.IP REG_NOTEOL
The NUL terminating
the string
does not end a line, so the `$' anchor should not match before it.
This does not affect the behavior of newlines under REG_NEWLINE.
.IP REG_STARTEND
The string is considered to start at
\fIstring\fR\ + \fIpmatch\fR[0].\fIrm_so\fR
and to have a terminating NUL located at
\fIstring\fR\ + \fIpmatch\fR[0].\fIrm_eo\fR
(there need not actually be a NUL at that location),
regardless of the value of
.IR nmatch .
See below for the definition of
.IR pmatch
and
.IR nmatch .
This is an extension,
compatible with but not specified by POSIX 1003.2,
and should be used with
caution in software intended to be portable to other systems.
Note that a non-zero \fIrm_so\fR does not imply REG_NOTBOL;
REG_STARTEND affects only the location of the string,
not how it is matched.
.PP
See
.ZR
for a discussion of what is matched in situations where an RE or a
portion thereof could match any of several substrings of
.IR string .
.PP
Normally,
.I regexec
returns 0 for success and the non-zero code REG_NOMATCH for failure.
Other non-zero error codes may be returned in exceptional situations;
see DIAGNOSTICS.
.PP
If REG_NOSUB was specified in the compilation of the RE,
or if
.I nmatch
is 0,
.I regexec
ignores the
.I pmatch
argument (but see below for the case where REG_STARTEND is specified).
Otherwise,
.I pmatch
points to an array of
.I nmatch
structures of type
.IR regmatch_t .
Such a structure has at least the members
.I rm_so
and
.IR rm_eo ,
both of type
.I regoff_t
(a signed arithmetic type at least as large as an
.I off_t
and a
.IR ssize_t ),
containing respectively the offset of the first character of a substring
and the offset of the first character after the end of the substring.
Offsets are measured from the beginning of the
.I string
argument given to
.IR regexec .
An empty substring is denoted by equal offsets,
both indicating the character following the empty substring.
.PP
The 0th member of the
.I pmatch
array is filled in to indicate what substring of
.I string
was matched by the entire RE.
Remaining members report what substring was matched by parenthesized
subexpressions within the RE;
member
.I i
reports subexpression
.IR i ,
with subexpressions counted (starting at 1) by the order of their opening
parentheses in the RE, left to right.
Unused entries in the array\(emcorresponding either to subexpressions that
did not participate in the match at all, or to subexpressions that do not
exist in the RE (that is, \fIi\fR\ > \fIpreg\fR\->\fIre_nsub\fR)\(emhave both
.I rm_so
and
.I rm_eo
set to \-1.
If a subexpression participated in the match several times,
the reported substring is the last one it matched.
(Note, as an example in particular, that when the RE `(b*)+' matches `bbb',
the parenthesized subexpression matches each of the three `b's and then
an infinite number of empty strings following the last `b',
so the reported substring is one of the empties.)
.PP
If REG_STARTEND is specified,
.I pmatch
must point to at least one
.I regmatch_t
(even if
.I nmatch
is 0 or REG_NOSUB was specified),
to hold the input offsets for REG_STARTEND.
Use for output is still entirely controlled by
.IR nmatch ;
if
.I nmatch
is 0 or REG_NOSUB was specified,
the value of
.IR pmatch [0]
will not be changed by a successful
.IR regexec .
.PP
.I Regerror
maps a non-zero
.I errcode
from either
.I regcomp
or
.I regexec
to a human-readable, printable message.
If
.I preg
is non-NULL,
the error code should have arisen from use of
the
.I regex_t
pointed to by
.IR preg ,
and if the error code came from
.IR regcomp ,
it should have been the result from the most recent
.I regcomp
using that
.IR regex_t .
.RI ( Regerror
may be able to supply a more detailed message using information
from the
.IR regex_t .)
.I Regerror
places the NUL-terminated message into the buffer pointed to by
.IR errbuf ,
limiting the length (including the NUL) to at most
.I errbuf_size
bytes.
If the whole message won't fit,
as much of it as will fit before the terminating NUL is supplied.
In any case,
the returned value is the size of buffer needed to hold the whole
message (including terminating NUL).
If
.I errbuf_size
is 0,
.I errbuf
is ignored but the return value is still correct.
.PP
If the
.I errcode
given to
.I regerror
is first ORed with REG_ITOA,
the ``message'' that results is the printable name of the error code,
e.g. ``REG_NOMATCH'',
rather than an explanation thereof.
If
.I errcode
is REG_ATOI,
then
.I preg
shall be non-NULL and the
.I re_endp
member of the structure it points to
must point to the printable name of an error code;
in this case, the result in
.I errbuf
is the decimal digits of
the numeric value of the error code
(0 if the name is not recognized).
REG_ITOA and REG_ATOI are intended primarily as debugging facilities;
they are extensions,
compatible with but not specified by POSIX 1003.2,
and should be used with
caution in software intended to be portable to other systems.
Be warned also that they are considered experimental and changes are possible.
.PP
.I Regfree
frees any dynamically-allocated storage associated with the compiled RE
pointed to by
.IR preg .
The remaining
.I regex_t
is no longer a valid compiled RE
and the effect of supplying it to
.I regexec
or
.I regerror
is undefined.
.PP
None of these functions references global variables except for tables
of constants;
all are safe for use from multiple threads if the arguments are safe.
.SH IMPLEMENTATION CHOICES
There are a number of decisions that 1003.2 leaves up to the implementor,
either by explicitly saying ``undefined'' or by virtue of them being
forbidden by the RE grammar.
This implementation treats them as follows.
.PP
See
.ZR
for a discussion of the definition of case-independent matching.
.PP
There is no particular limit on the length of REs,
except insofar as memory is limited.
Memory usage is approximately linear in RE size, and largely insensitive
to RE complexity, except for bounded repetitions.
See BUGS for one short RE using them
that will run almost any system out of memory.
.PP
A backslashed character other than one specifically given a magic meaning
by 1003.2 (such magic meanings occur only in obsolete [``basic''] REs)
is taken as an ordinary character.
.PP
Any unmatched [ is a REG_EBRACK error.
.PP
Equivalence classes cannot begin or end bracket-expression ranges.
The endpoint of one range cannot begin another.
.PP
RE_DUP_MAX, the limit on repetition counts in bounded repetitions, is 255.
.PP
A repetition operator (?, *, +, or bounds) cannot follow another
repetition operator.
A repetition operator cannot begin an expression or subexpression
or follow `^' or `|'.
.PP
`|' cannot appear first or last in a (sub)expression or after another `|',
i.e. an operand of `|' cannot be an empty subexpression.
An empty parenthesized subexpression, `()', is legal and matches an
empty (sub)string.
An empty string is not a legal RE.
.PP
A `{' followed by a digit is considered the beginning of bounds for a
bounded repetition, which must then follow the syntax for bounds.
A `{' \fInot\fR followed by a digit is considered an ordinary character.
.PP
`^' and `$' beginning and ending subexpressions in obsolete (``basic'')
REs are anchors, not ordinary characters.
.SH SEE ALSO
grep(1), re_format(7)
.PP
POSIX 1003.2, sections 2.8 (Regular Expression Notation)
and
B.5 (C Binding for Regular Expression Matching).
.SH DIAGNOSTICS
Non-zero error codes from
.I regcomp
and
.I regexec
include the following:
.PP
.nf
.ta \w'REG_ECOLLATE'u+3n
REG_NOMATCH no pattern match found
REG_BADPAT invalid regex struct
REG_ECOLLATE invalid collating element
REG_ECTYPE invalid character class
REG_EESCAPE trailing backslash (\e)
REG_ESUBREG invalid backreference number
REG_EBRACK brackets [ ] not balanced
REG_EPAREN parentheses ( ) not balanced
REG_EBRACE braces { } not balanced
REG_BADBR invalid repetition count(s) in { }
REG_ERANGE invalid character range in [ ]
REG_ESPACE ran out of memory
REG_BADRPT ?, *, or + operand invalid
REG_EMPTY empty expression or subexpression
REG_ASSERT ``can't happen''\(emyou found a bug
REG_INVARG invalid argument, e.g. negative-length string
.fi
.SH HISTORY
Originally written by Henry Spencer.
Altered for inclusion in the 4.4BSD distribution.
.SH BUGS
This is an alpha release with known defects.
Please report problems.
.PP
There is one known functionality bug.
The implementation of internationalization is incomplete:
the locale is always assumed to be the default one of 1003.2,
and only the collating elements etc. of that locale are available.
.PP
The back-reference code is subtle and doubts linger about its correctness
in complex cases.
.PP
.I Regexec
performance is poor.
This will improve with later releases.
.I Nmatch
exceeding 0 is expensive;
.I nmatch
exceeding 1 is worse.
.I Regexec
is largely insensitive to RE complexity \fIexcept\fR that back
references are massively expensive.
RE length does matter; in particular, there is a strong speed bonus
for keeping RE length under about 30 characters,
with most special characters counting roughly double.
.PP
.I Regcomp
implements bounded repetitions by macro expansion,
which is costly in time and space if counts are large
or bounded repetitions are nested.
An RE like, say,
`((((a{1,100}){1,100}){1,100}){1,100}){1,100}'
will (eventually) run almost any existing machine out of swap space.
.PP
There are suspected problems with response to obscure error conditions.
Notably,
certain kinds of internal overflow,
produced only by truly enormous REs or by multiply nested bounded repetitions,
are probably not handled well.
.PP
Due to a mistake in 1003.2, things like `a)b' are legal REs because `)' is
a special character only in the presence of a previous unmatched `('.
This can't be fixed until the spec is fixed.
.PP
The standard's definition of back references is vague.
For example, does
`a\e(\e(b\e)*\e2\e)*d' match `abbbd'?
Until the standard is clarified,
behavior in such cases should not be relied on.
.PP
The implementation of word-boundary matching is a bit of a kludge,
and bugs may lurk in combinations of word-boundary matching and anchoring.
src/backend/regex/regexec.c
View file @ 7bcc6d98
/*- /*
* Copyright (c) 1992, 1993, 1994 Henry Spencer. * re_*exec and friends - match REs
* Copyright (c) 1992, 1993, 1994 *
* The Regents of the University of California. All rights reserved. * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
* *
* This code is derived from software contributed to Berkeley by * Redistribution and use in source and binary forms -- with or without
* Henry Spencer. * modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
* *
* Redistribution and use in source and binary forms, with or without * I'd appreciate being given credit for this package in the documentation
* modification, are permitted provided that the following conditions * of software which uses it, but that is not a requirement.
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* SUCH DAMAGE. *
* $Header: /cvsroot/pgsql/src/backend/regex/regexec.c,v 1.21 2003/02/05 17:41:33 tgl Exp $
* *
* @(#)regexec.c 8.3 (Berkeley) 3/20/94
*/ */
#include "postgres.h" #include "regex/regguts.h"
/* lazy-DFA representation */
struct arcp { /* "pointer" to an outarc */
struct sset *ss;
color co;
};
struct sset { /* state set */
unsigned *states; /* pointer to bitvector */
unsigned hash; /* hash of bitvector */
# define HASH(bv, nw) (((nw) == 1) ? *(bv) : hash(bv, nw))
# define HIT(h,bv,ss,nw) ((ss)->hash == (h) && ((nw) == 1 || \
memcmp(VS(bv), VS((ss)->states), (nw)*sizeof(unsigned)) == 0))
int flags;
# define STARTER 01 /* the initial state set */
# define POSTSTATE 02 /* includes the goal state */
# define LOCKED 04 /* locked in cache */
# define NOPROGRESS 010 /* zero-progress state set */
struct arcp ins; /* chain of inarcs pointing here */
chr *lastseen; /* last entered on arrival here */
struct sset **outs; /* outarc vector indexed by color */
struct arcp *inchain; /* chain-pointer vector for outarcs */
};
struct dfa {
int nssets; /* size of cache */
int nssused; /* how many entries occupied yet */
int nstates; /* number of states */
int ncolors; /* length of outarc and inchain vectors */
int wordsper; /* length of state-set bitvectors */
struct sset *ssets; /* state-set cache */
unsigned *statesarea; /* bitvector storage */
unsigned *work; /* pointer to work area within statesarea */
struct sset **outsarea; /* outarc-vector storage */
struct arcp *incarea; /* inchain storage */
struct cnfa *cnfa;
struct colormap *cm;
chr *lastpost; /* location of last cache-flushed success */
chr *lastnopr; /* location of last cache-flushed NOPROGRESS */
struct sset *search; /* replacement-search-pointer memory */
int cptsmalloced; /* were the areas individually malloced? */
char *mallocarea; /* self, or master malloced area, or NULL */
};
#define WORK 1 /* number of work bitvectors needed */
/* setup for non-malloc allocation for small cases */
#define FEWSTATES 20 /* must be less than UBITS */
#define FEWCOLORS 15
struct smalldfa {
struct dfa dfa;
struct sset ssets[FEWSTATES*2];
unsigned statesarea[FEWSTATES*2 + WORK];
struct sset *outsarea[FEWSTATES*2 * FEWCOLORS];
struct arcp incarea[FEWSTATES*2 * FEWCOLORS];
};
#define DOMALLOC ((struct smalldfa *)NULL) /* force malloc */
/* internal variables, bundled for easy passing around */
struct vars {
regex_t *re;
struct guts *g;
int eflags; /* copies of arguments */
size_t nmatch;
regmatch_t *pmatch;
rm_detail_t *details;
chr *start; /* start of string */
chr *stop; /* just past end of string */
int err; /* error code if any (0 none) */
regoff_t *mem; /* memory vector for backtracking */
struct smalldfa dfa1;
struct smalldfa dfa2;
};
#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
#define ISERR() VISERR(v)
#define VERR(vv,e) (((vv)->err) ? (vv)->err : ((vv)->err = (e)))
#define ERR(e) VERR(v, e) /* record an error */
#define NOERR() {if (ISERR()) return v->err;} /* if error seen, return it */
#define OFF(p) ((p) - v->start)
#define LOFF(p) ((long)OFF(p))
/* /*
* the outer shell of regexec() * forward declarations
*
* This file includes engine.c *twice*, after muchos fiddling with the
* macros that code uses. This lets the same code operate on two different
* representations for state sets.
*/
#include <limits.h>
#include <ctype.h>
#include <assert.h>
#include "regex/regex.h"
#include "regex/utils.h"
#include "regex/regex2.h"
static int nope = 0; /* for use in asserts; shuts lint up */
/* macros for manipulating states, small version */
#define states long
#define states1 states /* for later use in regexec() decision */
#define CLEAR(v) ((v) = 0)
#define SET0(v, n) ((v) &= ~(1L << (n)))
#define SET1(v, n) ((v) |= (1L << (n)))
#define ISSET(v, n) ((v) & (1L << (n)))
#define ASSIGN(d, s) ((d) = (s))
#define EQ(a, b) ((a) == (b))
#define STATEVARS int dummy /* dummy version */
#define STATESETUP(m, n) /* nothing */
#define STATETEARDOWN(m) /* nothing */
#define SETUP(v) ((v) = 0)
#define onestate long
#define INIT(o, n) ((o) = (1L << (n)))
#define INC(o) ((o) <<= 1)
#define ISSTATEIN(v, o) ((v) & (o))
/* some abbreviations; note that some of these know variable names! */
/* do "if I'm here, I can also be there" etc without branches */
#define FWD(dst, src, n) ((dst) |= ((src) & (here)) << (n))
#define BACK(dst, src, n) ((dst) |= ((src) & (here)) >> (n))
#define ISSETBACK(v, n) ((v) & (here >> (n)))
/* function names */
#define SNAMES /* engine.c looks after details */
#include "engine.c"
/* now undo things */
#undef states
#undef CLEAR
#undef SET0
#undef SET1
#undef ISSET
#undef ASSIGN
#undef EQ
#undef STATEVARS
#undef STATESETUP
#undef STATETEARDOWN
#undef SETUP
#undef onestate
#undef INIT
#undef INC
#undef ISSTATEIN
#undef FWD
#undef BACK
#undef ISSETBACK
#undef SNAMES
/* macros for manipulating states, large version */
#define states char *
#define CLEAR(v) memset(v, 0, m->g->nstates)
#define SET0(v, n) ((v)[n] = 0)
#define SET1(v, n) ((v)[n] = 1)
#define ISSET(v, n) ((v)[n])
#define ASSIGN(d, s) memcpy(d, s, m->g->nstates)
#define EQ(a, b) (memcmp(a, b, m->g->nstates) == 0)
#define STATEVARS int vn; char *space
#define STATESETUP(m, nv) \
do { \
(m)->space = malloc((nv)*(m)->g->nstates); \
if ((m)->space == NULL) \
return(REG_ESPACE); \
(m)->vn = 0; \
} while (0)
#define STATETEARDOWN(m) \
do { \
free((m)->space); \
} while (0)
#define SETUP(v) ((v) = &m->space[m->vn++ * m->g->nstates])
#define onestate int
#define INIT(o, n) ((o) = (n))
#define INC(o) ((o)++)
#define ISSTATEIN(v, o) ((v)[o])
/* some abbreviations; note that some of these know variable names! */
/* do "if I'm here, I can also be there" etc without branches */
#define FWD(dst, src, n) ((dst)[here+(n)] |= (src)[here])
#define BACK(dst, src, n) ((dst)[here-(n)] |= (src)[here])
#define ISSETBACK(v, n) ((v)[here - (n)])
/* function names */
#define LNAMES /* flag */
#include "engine.c"
/*
* regexec - interface for matching
*
* We put this here so we can exploit knowledge of the state representation
* when choosing which matcher to call.
*/ */
int /* 0 success, REG_NOMATCH failure */ /* === regexec.c === */
pg_regexec(const regex_t *preg, const char *string, size_t nmatch, static int find (struct vars *, struct cnfa *, struct colormap *);
regmatch_t *pmatch, int eflags) static int cfind (struct vars *, struct cnfa *, struct colormap *);
static int cfindloop (struct vars *, struct cnfa *, struct colormap *, struct dfa *, struct dfa *, chr **);
static void zapsubs (regmatch_t *, size_t);
static void zapmem (struct vars *, struct subre *);
static void subset (struct vars *, struct subre *, chr *, chr *);
static int dissect (struct vars *, struct subre *, chr *, chr *);
static int condissect (struct vars *, struct subre *, chr *, chr *);
static int altdissect (struct vars *, struct subre *, chr *, chr *);
static int cdissect (struct vars *, struct subre *, chr *, chr *);
static int ccondissect (struct vars *, struct subre *, chr *, chr *);
static int crevdissect (struct vars *, struct subre *, chr *, chr *);
static int cbrdissect (struct vars *, struct subre *, chr *, chr *);
static int caltdissect (struct vars *, struct subre *, chr *, chr *);
/* === rege_dfa.c === */
static chr *longest (struct vars *, struct dfa *, chr *, chr *, int *);
static chr *shortest (struct vars *, struct dfa *, chr *, chr *, chr *, chr **, int *);
static chr *lastcold (struct vars *, struct dfa *);
static struct dfa *newdfa (struct vars *, struct cnfa *, struct colormap *, struct smalldfa *);
static void freedfa (struct dfa *);
static unsigned hash (unsigned *, int);
static struct sset *initialize (struct vars *, struct dfa *, chr *);
static struct sset *miss (struct vars *, struct dfa *, struct sset *, pcolor, chr *, chr *);
static int lacon (struct vars *, struct cnfa *, chr *, pcolor);
static struct sset *getvacant (struct vars *, struct dfa *, chr *, chr *);
static struct sset *pickss (struct vars *, struct dfa *, chr *, chr *);
/*
* pg_regexec - match regular expression
*/
int
pg_regexec(regex_t *re,
const chr *string,
size_t len,
rm_detail_t *details,
size_t nmatch,
regmatch_t pmatch[],
int flags)
{ {
struct re_guts *g = preg->re_g; struct vars var;
register struct vars *v = &var;
pg_wchar *str; int st;
int sts; size_t n;
int backref;
#ifdef REDEBUG # define LOCALMAT 20
#define GOODFLAGS(f) (f) regmatch_t mat[LOCALMAT];
#else # define LOCALMEM 40
#define GOODFLAGS(f) ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND)) regoff_t mem[LOCALMEM];
#endif
/* sanity checks */
if (preg->re_magic != MAGIC1 || g->magic != MAGIC2) if (re == NULL || string == NULL || re->re_magic != REMAGIC)
return REG_BADPAT; return REG_INVARG;
assert(!(g->iflags & BAD)); if (re->re_csize != sizeof(chr))
if (g->iflags & BAD) /* backstop for no-debug case */ return REG_MIXED;
return REG_BADPAT;
eflags = GOODFLAGS(eflags); /* setup */
v->re = re;
str = (pg_wchar *) malloc((strlen(string) + 1) * sizeof(pg_wchar)); v->g = (struct guts *)re->re_guts;
if (!str) if ((v->g->cflags&REG_EXPECT) && details == NULL)
return (REG_ESPACE); return REG_INVARG;
(void) pg_mb2wchar((unsigned char *) string, str); if (v->g->info&REG_UIMPOSSIBLE)
if (g->nstates <= CHAR_BIT * sizeof(states1) && !(eflags & REG_LARGE)) return REG_NOMATCH;
sts = smatcher(g, str, nmatch, pmatch, eflags); backref = (v->g->info&REG_UBACKREF) ? 1 : 0;
v->eflags = flags;
if (v->g->cflags&REG_NOSUB)
nmatch = 0; /* override client */
v->nmatch = nmatch;
if (backref) {
/* need work area */
if (v->g->nsub + 1 <= LOCALMAT)
v->pmatch = mat;
else
v->pmatch = (regmatch_t *)MALLOC((v->g->nsub + 1) *
sizeof(regmatch_t));
if (v->pmatch == NULL)
return REG_ESPACE;
v->nmatch = v->g->nsub + 1;
} else
v->pmatch = pmatch;
v->details = details;
v->start = (chr *)string;
v->stop = (chr *)string + len;
v->err = 0;
if (backref) {
/* need retry memory */
assert(v->g->ntree >= 0);
n = (size_t)v->g->ntree;
if (n <= LOCALMEM)
v->mem = mem;
else else
sts = lmatcher(g, str, nmatch, pmatch, eflags); v->mem = (regoff_t *)MALLOC(n*sizeof(regoff_t));
free((char *) str); if (v->mem == NULL) {
return (sts); if (v->pmatch != pmatch && v->pmatch != mat)
FREE(v->pmatch);
return REG_ESPACE;
}
} else
v->mem = NULL;
/* do it */
assert(v->g->tree != NULL);
if (backref)
st = cfind(v, &v->g->tree->cnfa, &v->g->cmap);
else
st = find(v, &v->g->tree->cnfa, &v->g->cmap);
/* copy (portion of) match vector over if necessary */
if (st == REG_OKAY && v->pmatch != pmatch && nmatch > 0) {
zapsubs(pmatch, nmatch);
n = (nmatch < v->nmatch) ? nmatch : v->nmatch;
memcpy(VS(pmatch), VS(v->pmatch), n*sizeof(regmatch_t));
}
/* clean up */
if (v->pmatch != pmatch && v->pmatch != mat)
FREE(v->pmatch);
if (v->mem != NULL && v->mem != mem)
FREE(v->mem);
return st;
} }
/*
* find - find a match for the main NFA (no-complications case)
*/
static int
find(struct vars *v,
struct cnfa *cnfa,
struct colormap *cm)
{
struct dfa *s;
struct dfa *d;
chr *begin;
chr *end = NULL;
chr *cold;
chr *open; /* open and close of range of possible starts */
chr *close;
int hitend;
int shorter = (v->g->tree->flags&SHORTER) ? 1 : 0;
/* first, a shot with the search RE */
s = newdfa(v, &v->g->search, cm, &v->dfa1);
assert(!(ISERR() && s != NULL));
NOERR();
MDEBUG(("\nsearch at %ld\n", LOFF(v->start)));
cold = NULL;
close = shortest(v, s, v->start, v->start, v->stop, &cold, (int *)NULL);
freedfa(s);
NOERR();
if (v->g->cflags&REG_EXPECT) {
assert(v->details != NULL);
if (cold != NULL)
v->details->rm_extend.rm_so = OFF(cold);
else
v->details->rm_extend.rm_so = OFF(v->stop);
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
}
if (close == NULL) /* not found */
return REG_NOMATCH;
if (v->nmatch == 0) /* found, don't need exact location */
return REG_OKAY;
/* find starting point and match */
assert(cold != NULL);
open = cold;
cold = NULL;
MDEBUG(("between %ld and %ld\n", LOFF(open), LOFF(close)));
d = newdfa(v, cnfa, cm, &v->dfa1);
assert(!(ISERR() && d != NULL));
NOERR();
for (begin = open; begin <= close; begin++) {
MDEBUG(("\nfind trying at %ld\n", LOFF(begin)));
if (shorter)
end = shortest(v, d, begin, begin, v->stop,
(chr **)NULL, &hitend);
else
end = longest(v, d, begin, v->stop, &hitend);
NOERR();
if (hitend && cold == NULL)
cold = begin;
if (end != NULL)
break; /* NOTE BREAK OUT */
}
assert(end != NULL); /* search RE succeeded so loop should */
freedfa(d);
/* and pin down details */
assert(v->nmatch > 0);
v->pmatch[0].rm_so = OFF(begin);
v->pmatch[0].rm_eo = OFF(end);
if (v->g->cflags&REG_EXPECT) {
if (cold != NULL)
v->details->rm_extend.rm_so = OFF(cold);
else
v->details->rm_extend.rm_so = OFF(v->stop);
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
}
if (v->nmatch == 1) /* no need for submatches */
return REG_OKAY;
/* submatches */
zapsubs(v->pmatch, v->nmatch);
return dissect(v, v->g->tree, begin, end);
}
/*
* cfind - find a match for the main NFA (with complications)
*/
static int
cfind(struct vars *v,
struct cnfa *cnfa,
struct colormap *cm)
{
struct dfa *s;
struct dfa *d;
chr *cold;
int ret;
s = newdfa(v, &v->g->search, cm, &v->dfa1);
NOERR();
d = newdfa(v, cnfa, cm, &v->dfa2);
if (ISERR()) {
assert(d == NULL);
freedfa(s);
return v->err;
}
ret = cfindloop(v, cnfa, cm, d, s, &cold);
freedfa(d);
freedfa(s);
NOERR();
if (v->g->cflags&REG_EXPECT) {
assert(v->details != NULL);
if (cold != NULL)
v->details->rm_extend.rm_so = OFF(cold);
else
v->details->rm_extend.rm_so = OFF(v->stop);
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
}
return ret;
}
/*
* cfindloop - the heart of cfind
*/
static int
cfindloop(struct vars *v,
struct cnfa *cnfa,
struct colormap *cm,
struct dfa *d,
struct dfa *s,
chr **coldp) /* where to put coldstart pointer */
{
chr *begin;
chr *end;
chr *cold;
chr *open; /* open and close of range of possible starts */
chr *close;
chr *estart;
chr *estop;
int er;
int shorter = v->g->tree->flags&SHORTER;
int hitend;
assert(d != NULL && s != NULL);
cold = NULL;
close = v->start;
do {
MDEBUG(("\ncsearch at %ld\n", LOFF(close)));
close = shortest(v, s, close, close, v->stop, &cold, (int *)NULL);
if (close == NULL)
break; /* NOTE BREAK */
assert(cold != NULL);
open = cold;
cold = NULL;
MDEBUG(("cbetween %ld and %ld\n", LOFF(open), LOFF(close)));
for (begin = open; begin <= close; begin++) {
MDEBUG(("\ncfind trying at %ld\n", LOFF(begin)));
estart = begin;
estop = v->stop;
for (;;) {
if (shorter)
end = shortest(v, d, begin, estart,
estop, (chr **)NULL, &hitend);
else
end = longest(v, d, begin, estop,
&hitend);
if (hitend && cold == NULL)
cold = begin;
if (end == NULL)
break; /* NOTE BREAK OUT */
MDEBUG(("tentative end %ld\n", LOFF(end)));
zapsubs(v->pmatch, v->nmatch);
zapmem(v, v->g->tree);
er = cdissect(v, v->g->tree, begin, end);
if (er == REG_OKAY) {
if (v->nmatch > 0) {
v->pmatch[0].rm_so = OFF(begin);
v->pmatch[0].rm_eo = OFF(end);
}
*coldp = cold;
return REG_OKAY;
}
if (er != REG_NOMATCH) {
ERR(er);
return er;
}
if ((shorter) ? end == estop : end == begin) {
/* no point in trying again */
*coldp = cold;
return REG_NOMATCH;
}
/* go around and try again */
if (shorter)
estart = end + 1;
else
estop = end - 1;
}
}
} while (close < v->stop);
*coldp = cold;
return REG_NOMATCH;
}
/*
* zapsubs - initialize the subexpression matches to "no match"
*/
static void
zapsubs(regmatch_t *p,
size_t n)
{
size_t i;
for (i = n-1; i > 0; i--) {
p[i].rm_so = -1;
p[i].rm_eo = -1;
}
}
/*
* zapmem - initialize the retry memory of a subtree to zeros
*/
static void
zapmem(struct vars *v,
struct subre *t)
{
if (t == NULL)
return;
assert(v->mem != NULL);
v->mem[t->retry] = 0;
if (t->op == '(') {
assert(t->subno > 0);
v->pmatch[t->subno].rm_so = -1;
v->pmatch[t->subno].rm_eo = -1;
}
if (t->left != NULL)
zapmem(v, t->left);
if (t->right != NULL)
zapmem(v, t->right);
}
/*
* subset - set any subexpression relevant to a successful subre
*/
static void
subset(struct vars *v,
struct subre *sub,
chr *begin,
chr *end)
{
int n = sub->subno;
assert(n > 0);
if ((size_t)n >= v->nmatch)
return;
MDEBUG(("setting %d\n", n));
v->pmatch[n].rm_so = OFF(begin);
v->pmatch[n].rm_eo = OFF(end);
}
/*
* dissect - determine subexpression matches (uncomplicated case)
*/
static int /* regexec return code */
dissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
assert(t != NULL);
MDEBUG(("dissect %ld-%ld\n", LOFF(begin), LOFF(end)));
switch (t->op) {
case '=': /* terminal node */
assert(t->left == NULL && t->right == NULL);
return REG_OKAY; /* no action, parent did the work */
break;
case '|': /* alternation */
assert(t->left != NULL);
return altdissect(v, t, begin, end);
break;
case 'b': /* back ref -- shouldn't be calling us! */
return REG_ASSERT;
break;
case '.': /* concatenation */
assert(t->left != NULL && t->right != NULL);
return condissect(v, t, begin, end);
break;
case '(': /* capturing */
assert(t->left != NULL && t->right == NULL);
assert(t->subno > 0);
subset(v, t, begin, end);
return dissect(v, t->left, begin, end);
break;
default:
return REG_ASSERT;
break;
}
}
/*
* condissect - determine concatenation subexpression matches (uncomplicated)
*/
static int /* regexec return code */
condissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
struct dfa *d;
struct dfa *d2;
chr *mid;
int i;
int shorter = (t->left->flags&SHORTER) ? 1 : 0;
chr *stop = (shorter) ? end : begin;
assert(t->op == '.');
assert(t->left != NULL && t->left->cnfa.nstates > 0);
assert(t->right != NULL && t->right->cnfa.nstates > 0);
d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
NOERR();
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, &v->dfa2);
if (ISERR()) {
assert(d2 == NULL);
freedfa(d);
return v->err;
}
/* pick a tentative midpoint */
if (shorter)
mid = shortest(v, d, begin, begin, end, (chr **)NULL,
(int *)NULL);
else
mid = longest(v, d, begin, end, (int *)NULL);
if (mid == NULL) {
freedfa(d);
freedfa(d2);
return REG_ASSERT;
}
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
/* iterate until satisfaction or failure */
while (longest(v, d2, mid, end, (int *)NULL) != end) {
/* that midpoint didn't work, find a new one */
if (mid == stop) {
/* all possibilities exhausted! */
MDEBUG(("no midpoint!\n"));
freedfa(d);
freedfa(d2);
return REG_ASSERT;
}
if (shorter)
mid = shortest(v, d, begin, mid+1, end, (chr **)NULL,
(int *)NULL);
else
mid = longest(v, d, begin, mid-1, (int *)NULL);
if (mid == NULL) {
/* failed to find a new one! */
MDEBUG(("failed midpoint!\n"));
freedfa(d);
freedfa(d2);
return REG_ASSERT;
}
MDEBUG(("new midpoint %ld\n", LOFF(mid)));
}
/* satisfaction */
MDEBUG(("successful\n"));
freedfa(d);
freedfa(d2);
i = dissect(v, t->left, begin, mid);
if (i != REG_OKAY)
return i;
return dissect(v, t->right, mid, end);
}
/*
* altdissect - determine alternative subexpression matches (uncomplicated)
*/
static int /* regexec return code */
altdissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
struct dfa *d;
int i;
assert(t != NULL);
assert(t->op == '|');
for (i = 0; t != NULL; t = t->right, i++) {
MDEBUG(("trying %dth\n", i));
assert(t->left != NULL && t->left->cnfa.nstates > 0);
d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
if (ISERR())
return v->err;
if (longest(v, d, begin, end, (int *)NULL) == end) {
MDEBUG(("success\n"));
freedfa(d);
return dissect(v, t->left, begin, end);
}
freedfa(d);
}
return REG_ASSERT; /* none of them matched?!? */
}
/*
* cdissect - determine subexpression matches (with complications)
* The retry memory stores the offset of the trial midpoint from begin,
* plus 1 so that 0 uniquely means "clean slate".
*/
static int /* regexec return code */
cdissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
int er;
assert(t != NULL);
MDEBUG(("cdissect %ld-%ld %c\n", LOFF(begin), LOFF(end), t->op));
switch (t->op) {
case '=': /* terminal node */
assert(t->left == NULL && t->right == NULL);
return REG_OKAY; /* no action, parent did the work */
break;
case '|': /* alternation */
assert(t->left != NULL);
return caltdissect(v, t, begin, end);
break;
case 'b': /* back ref -- shouldn't be calling us! */
assert(t->left == NULL && t->right == NULL);
return cbrdissect(v, t, begin, end);
break;
case '.': /* concatenation */
assert(t->left != NULL && t->right != NULL);
return ccondissect(v, t, begin, end);
break;
case '(': /* capturing */
assert(t->left != NULL && t->right == NULL);
assert(t->subno > 0);
er = cdissect(v, t->left, begin, end);
if (er == REG_OKAY)
subset(v, t, begin, end);
return er;
break;
default:
return REG_ASSERT;
break;
}
}
/*
* ccondissect - concatenation subexpression matches (with complications)
* The retry memory stores the offset of the trial midpoint from begin,
* plus 1 so that 0 uniquely means "clean slate".
*/
static int /* regexec return code */
ccondissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
struct dfa *d;
struct dfa *d2;
chr *mid;
int er;
assert(t->op == '.');
assert(t->left != NULL && t->left->cnfa.nstates > 0);
assert(t->right != NULL && t->right->cnfa.nstates > 0);
if (t->left->flags&SHORTER) /* reverse scan */
return crevdissect(v, t, begin, end);
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
if (ISERR())
return v->err;
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
if (ISERR()) {
freedfa(d);
return v->err;
}
MDEBUG(("cconcat %d\n", t->retry));
/* pick a tentative midpoint */
if (v->mem[t->retry] == 0) {
mid = longest(v, d, begin, end, (int *)NULL);
if (mid == NULL) {
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
v->mem[t->retry] = (mid - begin) + 1;
} else {
mid = begin + (v->mem[t->retry] - 1);
MDEBUG(("working midpoint %ld\n", LOFF(mid)));
}
/* iterate until satisfaction or failure */
for (;;) {
/* try this midpoint on for size */
er = cdissect(v, t->left, begin, mid);
if (er == REG_OKAY &&
longest(v, d2, mid, end, (int *)NULL) == end &&
(er = cdissect(v, t->right, mid, end)) ==
REG_OKAY)
break; /* NOTE BREAK OUT */
if (er != REG_OKAY && er != REG_NOMATCH) {
freedfa(d);
freedfa(d2);
return er;
}
/* that midpoint didn't work, find a new one */
if (mid == begin) {
/* all possibilities exhausted */
MDEBUG(("%d no midpoint\n", t->retry));
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
mid = longest(v, d, begin, mid-1, (int *)NULL);
if (mid == NULL) {
/* failed to find a new one */
MDEBUG(("%d failed midpoint\n", t->retry));
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
v->mem[t->retry] = (mid - begin) + 1;
zapmem(v, t->left);
zapmem(v, t->right);
}
/* satisfaction */
MDEBUG(("successful\n"));
freedfa(d);
freedfa(d2);
return REG_OKAY;
}
/*
* crevdissect - determine backref shortest-first subexpression matches
* The retry memory stores the offset of the trial midpoint from begin,
* plus 1 so that 0 uniquely means "clean slate".
*/
static int /* regexec return code */
crevdissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
struct dfa *d;
struct dfa *d2;
chr *mid;
int er;
assert(t->op == '.');
assert(t->left != NULL && t->left->cnfa.nstates > 0);
assert(t->right != NULL && t->right->cnfa.nstates > 0);
assert(t->left->flags&SHORTER);
/* concatenation -- need to split the substring between parts */
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
if (ISERR())
return v->err;
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
if (ISERR()) {
freedfa(d);
return v->err;
}
MDEBUG(("crev %d\n", t->retry));
/* pick a tentative midpoint */
if (v->mem[t->retry] == 0) {
mid = shortest(v, d, begin, begin, end, (chr **)NULL, (int *)NULL);
if (mid == NULL) {
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
v->mem[t->retry] = (mid - begin) + 1;
} else {
mid = begin + (v->mem[t->retry] - 1);
MDEBUG(("working midpoint %ld\n", LOFF(mid)));
}
/* iterate until satisfaction or failure */
for (;;) {
/* try this midpoint on for size */
er = cdissect(v, t->left, begin, mid);
if (er == REG_OKAY &&
longest(v, d2, mid, end, (int *)NULL) == end &&
(er = cdissect(v, t->right, mid, end)) ==
REG_OKAY)
break; /* NOTE BREAK OUT */
if (er != REG_OKAY && er != REG_NOMATCH) {
freedfa(d);
freedfa(d2);
return er;
}
/* that midpoint didn't work, find a new one */
if (mid == end) {
/* all possibilities exhausted */
MDEBUG(("%d no midpoint\n", t->retry));
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
mid = shortest(v, d, begin, mid+1, end, (chr **)NULL, (int *)NULL);
if (mid == NULL) {
/* failed to find a new one */
MDEBUG(("%d failed midpoint\n", t->retry));
freedfa(d);
freedfa(d2);
return REG_NOMATCH;
}
MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
v->mem[t->retry] = (mid - begin) + 1;
zapmem(v, t->left);
zapmem(v, t->right);
}
/* satisfaction */
MDEBUG(("successful\n"));
freedfa(d);
freedfa(d2);
return REG_OKAY;
}
/*
* cbrdissect - determine backref subexpression matches
*/
static int /* regexec return code */
cbrdissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
int i;
int n = t->subno;
size_t len;
chr *paren;
chr *p;
chr *stop;
int min = t->min;
int max = t->max;
assert(t != NULL);
assert(t->op == 'b');
assert(n >= 0);
assert((size_t)n < v->nmatch);
MDEBUG(("cbackref n%d %d{%d-%d}\n", t->retry, n, min, max));
if (v->pmatch[n].rm_so == -1)
return REG_NOMATCH;
paren = v->start + v->pmatch[n].rm_so;
len = v->pmatch[n].rm_eo - v->pmatch[n].rm_so;
/* no room to maneuver -- retries are pointless */
if (v->mem[t->retry])
return REG_NOMATCH;
v->mem[t->retry] = 1;
/* special-case zero-length string */
if (len == 0) {
if (begin == end)
return REG_OKAY;
return REG_NOMATCH;
}
/* and too-short string */
assert(end >= begin);
if ((size_t)(end - begin) < len)
return REG_NOMATCH;
stop = end - len;
/* count occurrences */
i = 0;
for (p = begin; p <= stop && (i < max || max == INFINITY); p += len) {
if ((*v->g->compare)(paren, p, len) != 0)
break;
i++;
}
MDEBUG(("cbackref found %d\n", i));
/* and sort it out */
if (p != end) /* didn't consume all of it */
return REG_NOMATCH;
if (min <= i && (i <= max || max == INFINITY))
return REG_OKAY;
return REG_NOMATCH; /* out of range */
}
/*
* caltdissect - determine alternative subexpression matches (w. complications)
*/
static int /* regexec return code */
caltdissect(struct vars *v,
struct subre *t,
chr *begin, /* beginning of relevant substring */
chr *end) /* end of same */
{
struct dfa *d;
int er;
# define UNTRIED 0 /* not yet tried at all */
# define TRYING 1 /* top matched, trying submatches */
# define TRIED 2 /* top didn't match or submatches exhausted */
if (t == NULL)
return REG_NOMATCH;
assert(t->op == '|');
if (v->mem[t->retry] == TRIED)
return caltdissect(v, t->right, begin, end);
MDEBUG(("calt n%d\n", t->retry));
assert(t->left != NULL);
if (v->mem[t->retry] == UNTRIED) {
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
if (ISERR())
return v->err;
if (longest(v, d, begin, end, (int *)NULL) != end) {
freedfa(d);
v->mem[t->retry] = TRIED;
return caltdissect(v, t->right, begin, end);
}
freedfa(d);
MDEBUG(("calt matched\n"));
v->mem[t->retry] = TRYING;
}
er = cdissect(v, t->left, begin, end);
if (er != REG_NOMATCH)
return er;
v->mem[t->retry] = TRIED;
return caltdissect(v, t->right, begin, end);
}
#include "rege_dfa.c"
src/backend/regex/regfree.c
View file @ 7bcc6d98
/*- /*
* Copyright (c) 1992, 1993, 1994 Henry Spencer. * regfree - free an RE
* Copyright (c) 1992, 1993, 1994 *
* The Regents of the University of California. All rights reserved. * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
* *
* This code is derived from software contributed to Berkeley by * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* Henry Spencer. * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* *
* Redistribution and use in source and binary forms, with or without * $Header: /cvsroot/pgsql/src/backend/regex/regfree.c,v 1.16 2003/02/05 17:41:33 tgl Exp $
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* *
* @(#)regfree.c 8.3 (Berkeley) 3/20/94 * You might think that this could be incorporated into regcomp.c, and
* that would be a reasonable idea... except that this is a generic
* function (with a generic name), applicable to all compiled REs
* regardless of the size of their characters, whereas the stuff in
* regcomp.c gets compiled once per character size.
*/ */
#include "postgres.h" #include "regex/regguts.h"
#include "regex/regex.h"
#include "regex/utils.h"
#include "regex/regex2.h"
/* /*
* regfree - free everything * pg_regfree - free an RE (generic function, punts to RE-specific function)
*
* Ignoring invocation with NULL is a convenience.
*/ */
void void
pg_regfree(regex_t *preg) pg_regfree(regex_t *re)
{ {
struct re_guts *g; if (re == NULL)
if (preg->re_magic != MAGIC1) /* oops */
return; /* nice to complain, but hard */
g = preg->re_g;
if (g == NULL || g->magic != MAGIC2) /* oops again */
return; return;
preg->re_magic = 0; /* mark it invalid */ (*((struct fns *)re->re_fns)->free)(re);
g->magic = 0; /* mark it invalid */
if (preg->patsave != NULL)
free((char *) preg->patsave);
if (g->strip != NULL)
free((char *) g->strip);
if (g->sets != NULL)
free((char *) g->sets);
if (g->setbits != NULL)
free((char *) g->setbits);
if (g->must != NULL)
free(g->must);
free((char *) g);
} }
src/backend/regex/retest.c deleted 100644 → 0
View file @ 32c3db0f
/*
* a simple regexp debug program
*
* $Header: /cvsroot/pgsql/src/backend/regex/Attic/retest.c,v 1.5 2002/06/11 15:41:37 thomas Exp $
*/
#include "postgres.h"
#include "regex/regex.h"
int
main()
{
int sts;
regex_t re;
char buf[1024];
char *p;
printf("type in regexp string: ");
if (!fgets(buf, sizeof(buf), stdin))
exit(0);
p = strchr(buf, '\n');
if (p)
*p = '\0';
sts = pg_regcomp(&re, buf, 1);
printf("regcomp: parses \"%s\" and returns %d\n", buf, sts);
for (;;)
{
printf("type in target string: ");
if (!fgets(buf, sizeof(buf), stdin))
exit(0);
p = strchr(buf, '\n');
if (p)
*p = '\0';
sts = pg_regexec(&re, buf, 0, 0, 0);
printf("regexec: returns %d\n", sts);
}
}
void
elog(int lev, const char *fmt,...)
{
}
src/backend/utils/adt/regexp.c
View file @ 7bcc6d98
/*------------------------------------------------------------------------- /*-------------------------------------------------------------------------
* *
* regexp.c * regexp.c
* regular expression handling code. * Postgres' interface to the regular expression package.
* *
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California * Portions Copyright (c) 1994, Regents of the University of California
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/regexp.c,v 1.43 2002/09/22 17:27:23 tgl Exp $ * $Header: /cvsroot/pgsql/src/backend/utils/adt/regexp.c,v 1.44 2003/02/05 17:41:32 tgl Exp $
* *
* Alistair Crooks added the code for the regex caching * Alistair Crooks added the code for the regex caching
* agc - cached the regular expressions used - there's a good chance * agc - cached the regular expressions used - there's a good chance
...@@ -30,171 +30,189 @@ ...@@ -30,171 +30,189 @@
#include "postgres.h" #include "postgres.h"
#include "regex/regex.h" #include "regex/regex.h"
#include "mb/pg_wchar.h"
#include "utils/builtins.h" #include "utils/builtins.h"
#if defined(DISABLE_XOPEN_NLS)
#undef _XOPEN_SOURCE
#endif /* DISABLE_XOPEN_NLS */
/* this is the number of cached regular expressions held. */ /*
* We cache precompiled regular expressions using a "self organizing list"
* structure, in which recently-used items tend to be near the front.
* Whenever we use an entry, it's moved up to the front of the list.
* Over time, an item's average position corresponds to its frequency of use.
*
* When we first create an entry, it's inserted at the front of
* the array, dropping the entry at the end of the array if necessary to
* make room. (This might seem to be weighting the new entry too heavily,
* but if we insert new entries further back, we'll be unable to adjust to
* a sudden shift in the query mix where we are presented with MAX_CACHED_RES
* never-before-seen items used circularly. We ought to be able to handle
* that case, so we have to insert at the front.)
*
* Knuth mentions a variant strategy in which a used item is moved up just
* one place in the list. Although he says this uses fewer comparisons on
* average, it seems not to adapt very well to the situation where you have
* both some reusable patterns and a steady stream of non-reusable patterns.
* A reusable pattern that isn't used at least as often as non-reusable
* patterns are seen will "fail to keep up" and will drop off the end of the
* cache. With move-to-front, a reusable pattern is guaranteed to stay in
* the cache as long as it's used at least once in every MAX_CACHED_RES uses.
*/
/* this is the maximum number of cached regular expressions */
#ifndef MAX_CACHED_RES #ifndef MAX_CACHED_RES
#define MAX_CACHED_RES 32 #define MAX_CACHED_RES 32
#endif #endif
/* this structure describes a cached regular expression */ /* this structure describes one cached regular expression */
struct cached_re_str typedef struct cached_re_str
{ {
char *cre_s; /* pattern as null-terminated string */ text *cre_pat; /* original RE (untoasted TEXT form) */
int cre_type; /* compiled-type: extended,icase etc */ int cre_flags; /* compile flags: extended,icase etc */
regex_t cre_re; /* the compiled regular expression */ regex_t cre_re; /* the compiled regular expression */
unsigned long cre_lru; /* lru tag */ } cached_re_str;
};
static int rec = 0; /* # of cached re's */ static int num_res = 0; /* # of cached re's */
static struct cached_re_str rev[MAX_CACHED_RES]; /* cached re's */ static cached_re_str re_array[MAX_CACHED_RES]; /* cached re's */
static unsigned long lru; /* system lru tag */
static int pg_lastrec = 0;
/* attempt to compile `re' as an re, then match it against text */
/* cflags - flag to regcomp indicates case sensitivity */ /*
* RE_compile_and_execute - compile and execute a RE, caching if possible
*
* Returns TRUE on match, FALSE on no match
*
* text_re --- the pattern, expressed as an *untoasted* TEXT object
* dat --- the data to match against (need not be null-terminated)
* dat_len --- the length of the data string
* cflags --- compile options for the pattern
* nmatch, pmatch --- optional return area for match details
*
* Both pattern and data are given in the database encoding. We internally
* convert to array of pg_wchar which is what Spencer's regex package wants.
*/
static bool static bool
RE_compile_and_execute(text *text_re, char *text, int cflags, RE_compile_and_execute(text *text_re, unsigned char *dat, int dat_len,
int nmatch, regmatch_t *pmatch) int cflags, int nmatch, regmatch_t *pmatch)
{ {
char *re; int text_re_len = VARSIZE(text_re);
int oldest; pg_wchar *data;
size_t data_len;
pg_wchar *pattern;
size_t pattern_len;
int i; int i;
int regcomp_result; int regcomp_result;
int regexec_result;
cached_re_str re_temp;
/* Convert 'text' pattern to null-terminated string */ /* Convert data string to wide characters */
re = DatumGetCString(DirectFunctionCall1(textout, data = (pg_wchar *) palloc((dat_len + 1) * sizeof(pg_wchar));
PointerGetDatum(text_re))); data_len = pg_mb2wchar_with_len(dat, data, dat_len);
/* /*
* Find a previously compiled regular expression. Run the cache as a * Look for a match among previously compiled REs. Since the data
* ring buffer, starting the search from the previous match if any. * structure is self-organizing with most-used entries at the front,
* our search strategy can just be to scan from the front.
*/ */
i = pg_lastrec; for (i = 0; i < num_res; i++)
while (i < rec)
{
if (rev[i].cre_s != NULL)
{ {
if (strcmp(rev[i].cre_s, re) == 0 && if (memcmp(re_array[i].cre_pat, text_re, text_re_len) == 0 &&
rev[i].cre_type == cflags) re_array[i].cre_flags == cflags)
{ {
pg_lastrec = i;
rev[i].cre_lru = ++lru;
pfree(re);
return (pg_regexec(&rev[i].cre_re,
text, nmatch,
pmatch, 0) == 0);
}
}
i++;
/* /*
* If we were not at the first slot to start, then think about * Found a match; move it to front if not there already.
* wrapping if necessary.
*/ */
if (pg_lastrec != 0) if (i > 0)
{ {
if (i >= rec) re_temp = re_array[i];
i = 0; memmove(&re_array[1], &re_array[0], i * sizeof(cached_re_str));
else if (i == pg_lastrec) re_array[0] = re_temp;
break;
}
} }
/* we didn't find it - make room in the cache for it */ /* Perform RE match and return result */
if (rec >= MAX_CACHED_RES) regexec_result = pg_regexec(&re_array[0].cre_re,
{ data,
/* cache is full - find the oldest entry */ data_len,
for (oldest = 0, i = 1; i < rec; i++) NULL, /* no details */
{ nmatch,
if (rev[i].cre_lru < rev[oldest].cre_lru) pmatch,
oldest = i; 0);
pfree(data);
return (regexec_result == 0);
} }
} }
else
oldest = rec++;
/* if there was an old re, then de-allocate the space it used */ /*
if (rev[oldest].cre_s != (char *) NULL) * Couldn't find it, so try to compile the new RE. To avoid leaking
{ * resources on failure, we build into the re_temp local.
for (lru = i = 0; i < rec; i++) */
/* Convert pattern string to wide characters */
pattern = (pg_wchar *) palloc((text_re_len - VARHDRSZ + 1) * sizeof(pg_wchar));
pattern_len = pg_mb2wchar_with_len((unsigned char *) VARDATA(text_re),
pattern,
text_re_len - VARHDRSZ);
regcomp_result = pg_regcomp(&re_temp.cre_re,
pattern,
pattern_len,
cflags);
pfree(pattern);
if (regcomp_result != 0)
{ {
/* downweight all of the other cached entries */ /* re didn't compile */
rev[i].cre_lru = (rev[i].cre_lru - rev[oldest].cre_lru) / 2; char errMsg[100];
if (rev[i].cre_lru > lru)
lru = rev[i].cre_lru; pg_regerror(regcomp_result, &re_temp.cre_re, errMsg, sizeof(errMsg));
/* XXX should we pg_regfree here? */
elog(ERROR, "Invalid regular expression: %s", errMsg);
} }
pg_regfree(&rev[oldest].cre_re);
/* /*
* use malloc/free for the cre_s field because the storage has to * use malloc/free for the cre_pat field because the storage has to
* persist across transactions * persist across transactions
*/ */
free(rev[oldest].cre_s); re_temp.cre_pat = malloc(text_re_len);
rev[oldest].cre_s = (char *) NULL; if (re_temp.cre_pat == NULL)
}
/* compile the re */
regcomp_result = pg_regcomp(&rev[oldest].cre_re, re, cflags);
if (regcomp_result == 0)
{ {
pg_lastrec = oldest; pg_regfree(&re_temp.cre_re);
elog(ERROR, "Out of memory");
}
memcpy(re_temp.cre_pat, text_re, text_re_len);
re_temp.cre_flags = cflags;
/* /*
* use malloc/free for the cre_s field because the storage has to * Okay, we have a valid new item in re_temp; insert it into the
* persist across transactions * storage array. Discard last entry if needed.
*/ */
rev[oldest].cre_s = strdup(re); if (num_res >= MAX_CACHED_RES)
rev[oldest].cre_lru = ++lru;
rev[oldest].cre_type = cflags;
pfree(re);
/* agc - fixed an old typo here */
return (pg_regexec(&rev[oldest].cre_re, text,
nmatch, pmatch, 0) == 0);
}
else
{ {
char errMsg[1000]; --num_res;
Assert(num_res < MAX_CACHED_RES);
/* re didn't compile */ pg_regfree(&re_array[num_res].cre_re);
pg_regerror(regcomp_result, &rev[oldest].cre_re, errMsg, free(re_array[num_res].cre_pat);
sizeof(errMsg));
elog(ERROR, "Invalid regular expression: %s", errMsg);
} }
/* not reached */ if (num_res > 0)
return false; memmove(&re_array[1], &re_array[0], num_res * sizeof(cached_re_str));
}
/*
fixedlen_regexeq:
a generic fixed length regexp routine re_array[0] = re_temp;
s - the string to match against (not necessarily null-terminated) num_res++;
p - the pattern (as a text*)
charlen - the length of the string
*/
static bool
fixedlen_regexeq(char *s, text *p, int charlen, int cflags)
{
char *sterm;
bool result;
/* be sure sterm is null-terminated */ /* Perform RE match and return result */
sterm = (char *) palloc(charlen + 1); regexec_result = pg_regexec(&re_array[0].cre_re,
memcpy(sterm, s, charlen); data,
sterm[charlen] = '\0'; data_len,
NULL, /* no details */
nmatch,
pmatch,
0);
result = RE_compile_and_execute(p, sterm, cflags, 0, NULL); pfree(data);
pfree(sterm); return (regexec_result == 0);
return result;
} }
...@@ -208,10 +226,11 @@ nameregexeq(PG_FUNCTION_ARGS) ...@@ -208,10 +226,11 @@ nameregexeq(PG_FUNCTION_ARGS)
Name n = PG_GETARG_NAME(0); Name n = PG_GETARG_NAME(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(fixedlen_regexeq(NameStr(*n), PG_RETURN_BOOL(RE_compile_and_execute(p,
p, (unsigned char *) NameStr(*n),
strlen(NameStr(*n)), strlen(NameStr(*n)),
REG_EXTENDED)); REG_ADVANCED,
0, NULL));
} }
Datum Datum
...@@ -220,10 +239,11 @@ nameregexne(PG_FUNCTION_ARGS) ...@@ -220,10 +239,11 @@ nameregexne(PG_FUNCTION_ARGS)
Name n = PG_GETARG_NAME(0); Name n = PG_GETARG_NAME(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(!fixedlen_regexeq(NameStr(*n), PG_RETURN_BOOL(!RE_compile_and_execute(p,
p, (unsigned char *) NameStr(*n),
strlen(NameStr(*n)), strlen(NameStr(*n)),
REG_EXTENDED)); REG_ADVANCED,
0, NULL));
} }
Datum Datum
...@@ -232,10 +252,11 @@ textregexeq(PG_FUNCTION_ARGS) ...@@ -232,10 +252,11 @@ textregexeq(PG_FUNCTION_ARGS)
text *s = PG_GETARG_TEXT_P(0); text *s = PG_GETARG_TEXT_P(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(fixedlen_regexeq(VARDATA(s), PG_RETURN_BOOL(RE_compile_and_execute(p,
p, (unsigned char *) VARDATA(s),
VARSIZE(s) - VARHDRSZ, VARSIZE(s) - VARHDRSZ,
REG_EXTENDED)); REG_ADVANCED,
0, NULL));
} }
Datum Datum
...@@ -244,10 +265,11 @@ textregexne(PG_FUNCTION_ARGS) ...@@ -244,10 +265,11 @@ textregexne(PG_FUNCTION_ARGS)
text *s = PG_GETARG_TEXT_P(0); text *s = PG_GETARG_TEXT_P(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(!fixedlen_regexeq(VARDATA(s), PG_RETURN_BOOL(!RE_compile_and_execute(p,
p, (unsigned char *) VARDATA(s),
VARSIZE(s) - VARHDRSZ, VARSIZE(s) - VARHDRSZ,
REG_EXTENDED)); REG_ADVANCED,
0, NULL));
} }
...@@ -258,55 +280,60 @@ textregexne(PG_FUNCTION_ARGS) ...@@ -258,55 +280,60 @@ textregexne(PG_FUNCTION_ARGS)
Datum Datum
texticregexeq(PG_FUNCTION_ARGS) nameicregexeq(PG_FUNCTION_ARGS)
{ {
text *s = PG_GETARG_TEXT_P(0); Name n = PG_GETARG_NAME(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(fixedlen_regexeq(VARDATA(s), PG_RETURN_BOOL(RE_compile_and_execute(p,
p, (unsigned char *) NameStr(*n),
VARSIZE(s) - VARHDRSZ, strlen(NameStr(*n)),
REG_ICASE | REG_EXTENDED)); REG_ICASE | REG_ADVANCED,
0, NULL));
} }
Datum Datum
texticregexne(PG_FUNCTION_ARGS) nameicregexne(PG_FUNCTION_ARGS)
{ {
text *s = PG_GETARG_TEXT_P(0); Name n = PG_GETARG_NAME(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(!fixedlen_regexeq(VARDATA(s), PG_RETURN_BOOL(!RE_compile_and_execute(p,
p, (unsigned char *) NameStr(*n),
VARSIZE(s) - VARHDRSZ, strlen(NameStr(*n)),
REG_ICASE | REG_EXTENDED)); REG_ICASE | REG_ADVANCED,
0, NULL));
} }
Datum Datum
nameicregexeq(PG_FUNCTION_ARGS) texticregexeq(PG_FUNCTION_ARGS)
{ {
Name n = PG_GETARG_NAME(0); text *s = PG_GETARG_TEXT_P(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(fixedlen_regexeq(NameStr(*n), PG_RETURN_BOOL(RE_compile_and_execute(p,
p, (unsigned char *) VARDATA(s),
strlen(NameStr(*n)), VARSIZE(s) - VARHDRSZ,
REG_ICASE | REG_EXTENDED)); REG_ICASE | REG_ADVANCED,
0, NULL));
} }
Datum Datum
nameicregexne(PG_FUNCTION_ARGS) texticregexne(PG_FUNCTION_ARGS)
{ {
Name n = PG_GETARG_NAME(0); text *s = PG_GETARG_TEXT_P(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
PG_RETURN_BOOL(!fixedlen_regexeq(NameStr(*n), PG_RETURN_BOOL(!RE_compile_and_execute(p,
p, (unsigned char *) VARDATA(s),
strlen(NameStr(*n)), VARSIZE(s) - VARHDRSZ,
REG_ICASE | REG_EXTENDED)); REG_ICASE | REG_ADVANCED,
0, NULL));
} }
/* textregexsubstr() /*
* textregexsubstr()
* Return a substring matched by a regular expression. * Return a substring matched by a regular expression.
*/ */
Datum Datum
...@@ -314,26 +341,20 @@ textregexsubstr(PG_FUNCTION_ARGS) ...@@ -314,26 +341,20 @@ textregexsubstr(PG_FUNCTION_ARGS)
{ {
text *s = PG_GETARG_TEXT_P(0); text *s = PG_GETARG_TEXT_P(0);
text *p = PG_GETARG_TEXT_P(1); text *p = PG_GETARG_TEXT_P(1);
char *sterm;
int len;
bool match; bool match;
regmatch_t pmatch[2]; regmatch_t pmatch[2];
/* be sure sterm is null-terminated */
len = VARSIZE(s) - VARHDRSZ;
sterm = (char *) palloc(len + 1);
memcpy(sterm, VARDATA(s), len);
sterm[len] = '\0';
/* /*
* We pass two regmatch_t structs to get info about the overall match * We pass two regmatch_t structs to get info about the overall match
* and the match for the first parenthesized subexpression (if any). * and the match for the first parenthesized subexpression (if any).
* If there is a parenthesized subexpression, we return what it matched; * If there is a parenthesized subexpression, we return what it matched;
* else return what the whole regexp matched. * else return what the whole regexp matched.
*/ */
match = RE_compile_and_execute(p, sterm, REG_EXTENDED, 2, pmatch); match = RE_compile_and_execute(p,
(unsigned char *) VARDATA(s),
pfree(sterm); VARSIZE(s) - VARHDRSZ,
REG_ADVANCED,
2, pmatch);
/* match? then return the substring matching the pattern */ /* match? then return the substring matching the pattern */
if (match) if (match)
......
src/include/regex/cclass.h deleted 100644 → 0
View file @ 32c3db0f
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)cclass.h 8.3 (Berkeley) 3/20/94
*/
/* character-class table */
static struct cclass
{
char *name;
char *chars;
char *multis;
} cclasses[] =
{
{
"alnum", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
0123456789", ""
},
{
"alpha", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz",
""
},
{
"blank", " \t", ""
},
{
"cntrl", "\007\b\t\n\v\f\r\1\2\3\4\5\6\16\17\20\21\22\23\24\
\25\26\27\30\31\32\33\34\35\36\37\177", ""
},
{
"digit", "0123456789", ""
},
{
"graph", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
""
},
{
"lower", "abcdefghijklmnopqrstuvwxyz",
""
},
{
"print", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~ ",
""
},
{
"punct", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
""
},
{
"space", "\t\n\v\f\r ", ""
},
{
"upper", "ABCDEFGHIJKLMNOPQRSTUVWXYZ",
""
},
{
"xdigit", "0123456789ABCDEFabcdef",
""
},
{
NULL, NULL, ""
}
};
src/include/regex/cname.h deleted 100644 → 0
View file @ 32c3db0f
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)cname.h 8.3 (Berkeley) 3/20/94
*/
/* character-name table */
static struct cname
{
char *name;
char code;
} cnames[] =
{
{
"NUL", '\0'
},
{
"SOH", '\001'
},
{
"STX", '\002'
},
{
"ETX", '\003'
},
{
"EOT", '\004'
},
{
"ENQ", '\005'
},
{
"ACK", '\006'
},
{
"BEL", '\007'
},
{
"alert", '\007'
},
{
"BS", '\010'
},
{
"backspace", '\b'
},
{
"HT", '\011'
},
{
"tab", '\t'
},
{
"LF", '\012'
},
{
"newline", '\n'
},
{
"VT", '\013'
},
{
"vertical-tab", '\v'
},
{
"FF", '\014'
},
{
"form-feed", '\f'
},
{
"CR", '\015'
},
{
"carriage-return", '\r'
},
{
"SO", '\016'
},
{
"SI", '\017'
},
{
"DLE", '\020'
},
{
"DC1", '\021'
},
{
"DC2", '\022'
},
{
"DC3", '\023'
},
{
"DC4", '\024'
},
{
"NAK", '\025'
},
{
"SYN", '\026'
},
{
"ETB", '\027'
},
{
"CAN", '\030'
},
{
"EM", '\031'
},
{
"SUB", '\032'
},
{
"ESC", '\033'
},
{
"IS4", '\034'
},
{
"FS", '\034'
},
{
"IS3", '\035'
},
{
"GS", '\035'
},
{
"IS2", '\036'
},
{
"RS", '\036'
},
{
"IS1", '\037'
},
{
"US", '\037'
},
{
"space", ' '
},
{
"exclamation-mark", '!'
},
{
"quotation-mark", '"'
},
{
"number-sign", '#'
},
{
"dollar-sign", '$'
},
{
"percent-sign", '%'
},
{
"ampersand", '&'
},
{
"apostrophe", '\''
},
{
"left-parenthesis", '('
},
{
"right-parenthesis", ')'
},
{
"asterisk", '*'
},
{
"plus-sign", '+'
},
{
"comma", ','
},
{
"hyphen", '-'
},
{
"hyphen-minus", '-'
},
{
"period", '.'
},
{
"full-stop", '.'
},
{
"slash", '/'
},
{
"solidus", '/'
},
{
"zero", '0'
},
{
"one", '1'
},
{
"two", '2'
},
{
"three", '3'
},
{
"four", '4'
},
{
"five", '5'
},
{
"six", '6'
},
{
"seven", '7'
},
{
"eight", '8'
},
{
"nine", '9'
},
{
"colon", ':'
},
{
"semicolon", ';'
},
{
"less-than-sign", '<'
},
{
"equals-sign", '='
},
{
"greater-than-sign", '>'
},
{
"question-mark", '?'
},
{
"commercial-at", '@'
},
{
"left-square-bracket", '['
},
{
"backslash", '\\'
},
{
"reverse-solidus", '\\'
},
{
"right-square-bracket", ']'
},
{
"circumflex", '^'
},
{
"circumflex-accent", '^'
},
{
"underscore", '_'
},
{
"low-line", '_'
},
{
"grave-accent", '`'
},
{
"left-brace", '{'
},
{
"left-curly-bracket", '{'
},
{
"vertical-line", '|'
},
{
"right-brace", '}'
},
{
"right-curly-bracket", '}'
},
{
"tilde", '~'
},
{
"DEL", '\177'
},
{
NULL, 0
}
};
src/include/regex/regcustom.h 0 → 100644
View file @ 7bcc6d98
/*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: regcustom.h,v 1.1 2003/02/05 17:41:32 tgl Exp $
*/
/* headers if any */
#include "postgres.h"
#include <ctype.h>
#include <limits.h>
#include "mb/pg_wchar.h"
/* overrides for regguts.h definitions, if any */
#define FUNCPTR(name, args) (*name) args
#define MALLOC(n) malloc(n)
#define FREE(p) free(VS(p))
#define REALLOC(p,n) realloc(VS(p),n)
/* internal character type and related */
typedef pg_wchar chr; /* the type itself */
typedef unsigned uchr; /* unsigned type that will hold a chr */
typedef int celt; /* type to hold chr, MCCE number, or NOCELT */
#define NOCELT (-1) /* celt value which is not valid chr or MCCE */
#define CHR(c) ((unsigned char) (c)) /* turn char literal into chr literal */
#define DIGITVAL(c) ((c)-'0') /* turn chr digit into its value */
#define CHRBITS 32 /* bits in a chr; must not use sizeof */
#define CHR_MIN 0x00000000 /* smallest and largest chr; the value */
#define CHR_MAX 0xfffffffe /* CHR_MAX-CHR_MIN+1 should fit in uchr */
/* functions operating on chr */
#define iscalnum(x) pg_isalnum(x)
#define iscalpha(x) pg_isalpha(x)
#define iscdigit(x) pg_isdigit(x)
#define iscspace(x) pg_isspace(x)
/* and pick up the standard header */
#include "regex.h"
src/include/regex/regerrs.h 0 → 100644
View file @ 7bcc6d98
/*
* $Id: regerrs.h,v 1.1 2003/02/05 17:41:32 tgl Exp $
*/
{ REG_OKAY, "REG_OKAY", "no errors detected" },
{ REG_NOMATCH, "REG_NOMATCH", "failed to match" },
{ REG_BADPAT, "REG_BADPAT", "invalid regexp (reg version 0.8)" },
{ REG_ECOLLATE, "REG_ECOLLATE", "invalid collating element" },
{ REG_ECTYPE, "REG_ECTYPE", "invalid character class" },
{ REG_EESCAPE, "REG_EESCAPE", "invalid escape \\ sequence" },
{ REG_ESUBREG, "REG_ESUBREG", "invalid backreference number" },
{ REG_EBRACK, "REG_EBRACK", "brackets [] not balanced" },
{ REG_EPAREN, "REG_EPAREN", "parentheses () not balanced" },
{ REG_EBRACE, "REG_EBRACE", "braces {} not balanced" },
{ REG_BADBR, "REG_BADBR", "invalid repetition count(s)" },
{ REG_ERANGE, "REG_ERANGE", "invalid character range" },
{ REG_ESPACE, "REG_ESPACE", "out of memory" },
{ REG_BADRPT, "REG_BADRPT", "quantifier operand invalid" },
{ REG_ASSERT, "REG_ASSERT", "\"can't happen\" -- you found a bug" },
{ REG_INVARG, "REG_INVARG", "invalid argument to regex function" },
{ REG_MIXED, "REG_MIXED", "character widths of regex and string differ" },
{ REG_BADOPT, "REG_BADOPT", "invalid embedded option" },
src/include/regex/regex.h
View file @ 7bcc6d98
/*- #ifndef _REGEX_H_
* Copyright (c) 1992 Henry Spencer. #define _REGEX_H_ /* never again */
* Copyright (c) 1992, 1993 /*
* The Regents of the University of California. All rights reserved. * regular expressions
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
* *
* This code is derived from software contributed to Berkeley by * Development of this software was funded, in part, by Cray Research Inc.,
* Henry Spencer of the University of Toronto. * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
* *
* Redistribution and use in source and binary forms, with or without * Redistribution and use in source and binary forms -- with or without
* modification, are permitted provided that the following conditions * modification -- are permitted for any purpose, provided that
* are met: * redistributions in source form retain this entire copyright notice and
* 1. Redistributions of source code must retain the above copyright * indicate the origin and nature of any modifications.
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * I'd appreciate being given credit for this package in the documentation
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * of software which uses it, but that is not a requirement.
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* *
* @(#)regex.h 8.2 (Berkeley) 1/3/94 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: regex.h,v 1.23 2003/02/05 17:41:32 tgl Exp $
*/ */
#ifndef _REGEX_H_ /*
#define _REGEX_H_ * Add your own defines, if needed, here.
*/
#include <sys/types.h>
#include "mb/pg_wchar.h" #include "mb/pg_wchar.h"
/* types */ /*
typedef off_t regoff_t; * interface types etc.
*/
/*
* regoff_t has to be large enough to hold either off_t or ssize_t,
* and must be signed; it's only a guess that long is suitable.
*/
typedef long regoff_t;
/*
* other interface types
*/
typedef struct /* the biggie, a compiled RE (or rather, a front end to same) */
{ typedef struct {
int re_magic; int re_magic; /* magic number */
size_t re_nsub; /* number of parenthesized subexpressions */ size_t re_nsub; /* number of subexpressions */
const pg_wchar *re_endp; /* end pointer for REG_PEND */ long re_info; /* information about RE */
struct re_guts *re_g; /* none of your business :-) */ # define REG_UBACKREF 000001
pg_wchar *patsave; /* me too :-) */ # define REG_ULOOKAHEAD 000002
# define REG_UBOUNDS 000004
# define REG_UBRACES 000010
# define REG_UBSALNUM 000020
# define REG_UPBOTCH 000040
# define REG_UBBS 000100
# define REG_UNONPOSIX 000200
# define REG_UUNSPEC 000400
# define REG_UUNPORT 001000
# define REG_ULOCALE 002000
# define REG_UEMPTYMATCH 004000
# define REG_UIMPOSSIBLE 010000
# define REG_USHORTEST 020000
int re_csize; /* sizeof(character) */
char *re_endp; /* backward compatibility kludge */
/* the rest is opaque pointers to hidden innards */
char *re_guts; /* `char *' is more portable than `void *' */
char *re_fns;
} regex_t; } regex_t;
typedef struct /* result reporting (may acquire more fields later) */
{ typedef struct {
regoff_t rm_so; /* start of match */ regoff_t rm_so; /* start of substring */
regoff_t rm_eo; /* end of match */ regoff_t rm_eo; /* end of substring */
} regmatch_t; } regmatch_t;
/* regcomp() flags */ /* supplementary control and reporting */
#define REG_BASIC 0000 typedef struct {
#define REG_EXTENDED 0001 regmatch_t rm_extend; /* see REG_EXPECT */
#define REG_ICASE 0002 } rm_detail_t;
#define REG_NOSUB 0004
#define REG_NEWLINE 0010
#define REG_NOSPEC 0020
#define REG_PEND 0040 /*
#define REG_DUMP 0200 * regex compilation flags
*/
/* regerror() flags */ #define REG_BASIC 000000 /* BREs (convenience) */
#define REG_NOMATCH 1 #define REG_EXTENDED 000001 /* EREs */
#define REG_BADPAT 2 #define REG_ADVF 000002 /* advanced features in EREs */
#define REG_ECOLLATE 3 #define REG_ADVANCED 000003 /* AREs (which are also EREs) */
#define REG_ECTYPE 4 #define REG_QUOTE 000004 /* no special characters, none */
#define REG_EESCAPE 5 #define REG_NOSPEC REG_QUOTE /* historical synonym */
#define REG_ESUBREG 6 #define REG_ICASE 000010 /* ignore case */
#define REG_EBRACK 7 #define REG_NOSUB 000020 /* don't care about subexpressions */
#define REG_EPAREN 8 #define REG_EXPANDED 000040 /* expanded format, white space & comments */
#define REG_EBRACE 9 #define REG_NLSTOP 000100 /* \n doesn't match . or [^ ] */
#define REG_BADBR 10 #define REG_NLANCH 000200 /* ^ matches after \n, $ before */
#define REG_ERANGE 11 #define REG_NEWLINE 000300 /* newlines are line terminators */
#define REG_ESPACE 12 #define REG_PEND 000400 /* ugh -- backward-compatibility hack */
#define REG_BADRPT 13 #define REG_EXPECT 001000 /* report details on partial/limited matches */
#define REG_EMPTY 14 #define REG_BOSONLY 002000 /* temporary kludge for BOS-only matches */
#define REG_ASSERT 15 #define REG_DUMP 004000 /* none of your business :-) */
#define REG_INVARG 16 #define REG_FAKE 010000 /* none of your business :-) */
#define REG_ATOI 255 /* convert name to number (!) */ #define REG_PROGRESS 020000 /* none of your business :-) */
#define REG_ITOA 0400 /* convert number to name (!) */
/* regexec() flags */
#define REG_NOTBOL 00001 /*
#define REG_NOTEOL 00002 * regex execution flags
#define REG_STARTEND 00004 */
#define REG_TRACE 00400 /* tracing of execution */ #define REG_NOTBOL 0001 /* BOS is not BOL */
#define REG_LARGE 01000 /* force large representation */ #define REG_NOTEOL 0002 /* EOS is not EOL */
#define REG_BACKR 02000 /* force use of backref code */ #define REG_STARTEND 0004 /* backward compatibility kludge */
#define REG_FTRACE 0010 /* none of your business */
extern int pg_regcomp(regex_t *preg, const char *pattern, int cflags); #define REG_MTRACE 0020 /* none of your business */
extern size_t pg_regerror(int errcode, const regex_t *preg, #define REG_SMALL 0040 /* none of your business */
char *errbuf, size_t errbuf_size);
extern int pg_regexec(const regex_t *preg, const char *string,
size_t nmatch, /*
regmatch_t *pmatch, int eflags); * error reporting
extern void pg_regfree(regex_t *preg); * Be careful if modifying the list of error codes -- the table used by
* regerror() is generated automatically from this file!
#endif /* !_REGEX_H_ */ */
#define REG_OKAY 0 /* no errors detected */
#define REG_NOMATCH 1 /* failed to match */
#define REG_BADPAT 2 /* invalid regexp */
#define REG_ECOLLATE 3 /* invalid collating element */
#define REG_ECTYPE 4 /* invalid character class */
#define REG_EESCAPE 5 /* invalid escape \ sequence */
#define REG_ESUBREG 6 /* invalid backreference number */
#define REG_EBRACK 7 /* brackets [] not balanced */
#define REG_EPAREN 8 /* parentheses () not balanced */
#define REG_EBRACE 9 /* braces {} not balanced */
#define REG_BADBR 10 /* invalid repetition count(s) */
#define REG_ERANGE 11 /* invalid character range */
#define REG_ESPACE 12 /* out of memory */
#define REG_BADRPT 13 /* quantifier operand invalid */
#define REG_ASSERT 15 /* "can't happen" -- you found a bug */
#define REG_INVARG 16 /* invalid argument to regex function */
#define REG_MIXED 17 /* character widths of regex and string differ */
#define REG_BADOPT 18 /* invalid embedded option */
/* two specials for debugging and testing */
#define REG_ATOI 101 /* convert error-code name to number */
#define REG_ITOA 102 /* convert error-code number to name */
/*
* the prototypes for exported functions
*/
extern int pg_regcomp(regex_t *, const pg_wchar *, size_t, int);
extern int pg_regexec(regex_t *, const pg_wchar *, size_t, rm_detail_t *, size_t, regmatch_t [], int);
extern void pg_regfree(regex_t *);
extern size_t pg_regerror(int, const regex_t *, char *, size_t);
#endif /* _REGEX_H_ */
src/include/regex/regex2.h deleted 100644 → 0
View file @ 32c3db0f
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)regex2.h 8.4 (Berkeley) 3/20/94
*/
#include <limits.h>
/*
* internals of regex_t
*/
#define MAGIC1 ((('r'^0200)<<8) | 'e')
/*
* The internal representation is a *strip*, a sequence of
* operators ending with an endmarker. (Some terminology etc. is a
* historical relic of earlier versions which used multiple strips.)
* Certain oddities in the representation are there to permit running
* the machinery backwards; in particular, any deviation from sequential
* flow must be marked at both its source and its destination. Some
* fine points:
*
* - OPLUS_ and O_PLUS are *inside* the loop they create.
* - OQUEST_ and O_QUEST are *outside* the bypass they create.
* - OCH_ and O_CH are *outside* the multi-way branch they create, while
* OOR1 and OOR2 are respectively the end and the beginning of one of
* the branches. Note that there is an implicit OOR2 following OCH_
* and an implicit OOR1 preceding O_CH.
*
* In state representations, an operator's bit is on to signify a state
* immediately *preceding* "execution" of that operator.
*/
typedef unsigned long sop; /* strip operator */
typedef long sopno;
#define OPRMASK ((sop) 0xf8000000)
#define OPDMASK ((sop) 0x07ffffff)
#define OPSHIFT ((unsigned)27)
#define OP(n) ((n)&OPRMASK)
#define OPND(n) ((n)&OPDMASK)
#define SOP(op, opnd) ((op)|(opnd))
/* operators meaning operand */
/* (back, fwd are offsets) */
#define OEND ((size_t)1<<OPSHIFT) /* endmarker - */
#define OCHAR ((size_t)2<<OPSHIFT) /* character unsigned char */
#define OBOL ((size_t)3<<OPSHIFT) /* left anchor - */
#define OEOL ((size_t)4<<OPSHIFT) /* right anchor - */
#define OANY ((size_t)5<<OPSHIFT) /* . - */
#define OANYOF ((size_t)6<<OPSHIFT) /* [...] set number */
#define OBACK_ ((size_t)7<<OPSHIFT) /* begin \d paren number */
#define O_BACK ((size_t)8<<OPSHIFT) /* end \d paren number */
#define OPLUS_ ((size_t)9<<OPSHIFT) /* + prefix fwd to suffix */
#define O_PLUS ((size_t)10<<OPSHIFT) /* + suffix back to prefix */
#define OQUEST_ ((size_t)11<<OPSHIFT) /* ? prefix fwd to suffix */
#define O_QUEST ((size_t)12<<OPSHIFT) /* ? suffix back to prefix */
#define OLPAREN ((size_t)13<<OPSHIFT) /* ( fwd to ) */
#define ORPAREN ((size_t)14<<OPSHIFT) /* ) back to ( */
#define OCH_ ((size_t)15<<OPSHIFT) /* begin choice fwd to OOR2 */
#define OOR1 ((size_t)16<<OPSHIFT) /* | pt. 1 back to OOR1 or
* OCH_ */
#define OOR2 ((size_t)17<<OPSHIFT) /* | pt. 2 fwd to OOR2 or
* O_CH */
#define O_CH ((size_t)18<<OPSHIFT) /* end choice back to OOR1 */
#define OBOW ((size_t)19<<OPSHIFT) /* begin word - */
#define OEOW ((size_t)20<<OPSHIFT) /* end word - */
/*
* Structure for [] character-set representation. Character sets are
* done as bit vectors, grouped 8 to a byte vector for compactness.
* The individual set therefore has both a pointer to the byte vector
* and a mask to pick out the relevant bit of each byte. A hash code
* simplifies testing whether two sets could be identical.
*
* This will get trickier for multicharacter collating elements. As
* preliminary hooks for dealing with such things, we also carry along
* a string of multi-character elements, and decide the size of the
* vectors at run time.
*/
typedef struct
{
uch *ptr; /* -> uch [csetsize] */
uch mask; /* bit within array */
pg_wchar hash; /* hash code */
unsigned int lc; /* leading character (character-set) */
size_t smultis;
char *multis; /* -> char[smulti] ab\0cd\0ef\0\0 */
} cset;
/* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
#define CHlc(c) (((unsigned)(c)&0xff0000)>>16)
#define CHadd(cs, c) ((cs)->ptr[(unsigned)(c)&0xffff] |= (cs)->mask, (cs)->hash += (unsigned)(c)&0xffff,\
(cs)->lc = CHlc(c))
#define CHsub(cs, c) ((cs)->ptr[(unsigned)(c)&0xffff] &= ~(cs)->mask, (cs)->hash -= (unsigned)(c)&0xffff)
#define CHIN(cs, c) ((cs)->ptr[(unsigned)(c)&0xffff] & (cs)->mask && \
((cs)->lc == CHlc(c)))
#define MCadd(p, cs, cp) mcadd(p, cs, cp) /* regcomp() internal
* fns */
#define MCsub(p, cs, cp) mcsub(p, cs, cp)
#define MCin(p, cs, cp) mcin(p, cs, cp)
/* stuff for character categories */
typedef unsigned char cat_t;
/*
* main compiled-expression structure
*/
struct re_guts
{
int magic;
#define MAGIC2 ((('R'^0200)<<8)|'E')
sop *strip; /* malloced area for strip */
int csetsize; /* number of bits in a cset vector */
int ncsets; /* number of csets in use */
cset *sets; /* -> cset [ncsets] */
uch *setbits; /* -> uch[csetsize][ncsets/CHAR_BIT] */
int cflags; /* copy of regcomp() cflags argument */
sopno nstates; /* = number of sops */
sopno firststate; /* the initial OEND (normally 0) */
sopno laststate; /* the final OEND */
int iflags; /* internal flags */
#define USEBOL 01 /* used ^ */
#define USEEOL 02 /* used $ */
#define BAD 04 /* something wrong */
int nbol; /* number of ^ used */
int neol; /* number of $ used */
int ncategories; /* how many character categories */
cat_t *categories; /* ->catspace[-CHAR_MIN] */
pg_wchar *must; /* match must contain this string */
int mlen; /* length of must */
size_t nsub; /* copy of re_nsub */
int backrefs; /* does it use back references? */
sopno nplus; /* how deep does it nest +s? */
/* catspace must be last */
cat_t catspace[1]; /* actually [NC] */
};
/* misc utilities */
#define OUT (16777216+1) /* 16777216 == 2^24 == 3 bytes */
#define ISWORD(c) (((c) >= 0 && (c) <= UCHAR_MAX) && \
(isalnum((unsigned char) (c)) || (c) == '_'))
src/include/regex/regguts.h 0 → 100644
View file @ 7bcc6d98
/*
* Internal interface definitions, etc., for the reg package
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: regguts.h,v 1.1 2003/02/05 17:41:32 tgl Exp $
*/
/*
* Environmental customization. It should not (I hope) be necessary to
* alter the file you are now reading -- regcustom.h should handle it all,
* given care here and elsewhere.
*/
#include "regcustom.h"
/*
* Things that regcustom.h might override.
*/
/* assertions */
#ifndef assert
# ifndef REG_DEBUG
# define NDEBUG /* no assertions */
# endif
#include <assert.h>
#endif
/* voids */
#ifndef DISCARD
#define DISCARD void /* for throwing values away */
#endif
#ifndef VS
#define VS(x) ((void *)(x)) /* cast something to generic ptr */
#endif
/* function-pointer declarator */
#ifndef FUNCPTR
#define FUNCPTR(name, args) (*name) args
#endif
/* memory allocation */
#ifndef MALLOC
#define MALLOC(n) malloc(n)
#endif
#ifndef REALLOC
#define REALLOC(p, n) realloc(VS(p), n)
#endif
#ifndef FREE
#define FREE(p) free(VS(p))
#endif
/* want size of a char in bits, and max value in bounded quantifiers */
#ifndef CHAR_BIT
#include <limits.h>
#endif
#ifndef _POSIX2_RE_DUP_MAX
#define _POSIX2_RE_DUP_MAX 255 /* normally from <limits.h> */
#endif
/*
* misc
*/
#define NOTREACHED 0
#define xxx 1
#define DUPMAX _POSIX2_RE_DUP_MAX
#define INFINITY (DUPMAX+1)
#define REMAGIC 0xfed7 /* magic number for main struct */
/*
* debugging facilities
*/
#ifdef REG_DEBUG
/* FDEBUG does finite-state tracing */
#define FDEBUG(arglist) { if (v->eflags&REG_FTRACE) printf arglist; }
/* MDEBUG does higher-level tracing */
#define MDEBUG(arglist) { if (v->eflags&REG_MTRACE) printf arglist; }
#else
#define FDEBUG(arglist) {}
#define MDEBUG(arglist) {}
#endif
/*
* bitmap manipulation
*/
#define UBITS (CHAR_BIT * sizeof(unsigned))
#define BSET(uv, sn) ((uv)[(sn)/UBITS] |= (unsigned)1 << ((sn)%UBITS))
#define ISBSET(uv, sn) ((uv)[(sn)/UBITS] & ((unsigned)1 << ((sn)%UBITS)))
/*
* We dissect a chr into byts for colormap table indexing. Here we define
* a byt, which will be the same as a byte on most machines... The exact
* size of a byt is not critical, but about 8 bits is good, and extraction
* of 8-bit chunks is sometimes especially fast.
*/
#ifndef BYTBITS
#define BYTBITS 8 /* bits in a byt */
#endif
#define BYTTAB (1<<BYTBITS) /* size of table with one entry per byt value */
#define BYTMASK (BYTTAB-1) /* bit mask for byt */
#define NBYTS ((CHRBITS+BYTBITS-1)/BYTBITS)
/* the definition of GETCOLOR(), below, assumes NBYTS <= 4 */
/*
* As soon as possible, we map chrs into equivalence classes -- "colors" --
* which are of much more manageable number.
*/
typedef short color; /* colors of characters */
typedef int pcolor; /* what color promotes to */
#define COLORLESS (-1) /* impossible color */
#define WHITE 0 /* default color, parent of all others */
/*
* A colormap is a tree -- more precisely, a DAG -- indexed at each level
* by a byt of the chr, to map the chr to a color efficiently. Because
* lower sections of the tree can be shared, it can exploit the usual
* sparseness of such a mapping table. The tree is always NBYTS levels
* deep (in the past it was shallower during construction but was "filled"
* to full depth at the end of that); areas that are unaltered as yet point
* to "fill blocks" which are entirely WHITE in color.
*/
/* the tree itself */
struct colors {
color ccolor[BYTTAB];
};
struct ptrs {
union tree *pptr[BYTTAB];
};
union tree {
struct colors colors;
struct ptrs ptrs;
};
#define tcolor colors.ccolor
#define tptr ptrs.pptr
/* internal per-color structure for the color machinery */
struct colordesc {
uchr nchrs; /* number of chars of this color */
color sub; /* open subcolor (if any); free chain ptr */
# define NOSUB COLORLESS
struct arc *arcs; /* color chain */
int flags;
# define FREECOL 01 /* currently free */
# define PSEUDO 02 /* pseudocolor, no real chars */
# define UNUSEDCOLOR(cd) ((cd)->flags&FREECOL)
union tree *block; /* block of solid color, if any */
};
/* the color map itself */
struct colormap {
int magic;
# define CMMAGIC 0x876
struct vars *v; /* for compile error reporting */
size_t ncds; /* number of colordescs */
size_t max; /* highest in use */
color free; /* beginning of free chain (if non-0) */
struct colordesc *cd;
# define CDEND(cm) (&(cm)->cd[(cm)->max + 1])
# define NINLINECDS ((size_t)10)
struct colordesc cdspace[NINLINECDS];
union tree tree[NBYTS]; /* tree top, plus fill blocks */
};
/* optimization magic to do fast chr->color mapping */
#define B0(c) ((c) & BYTMASK)
#define B1(c) (((c)>>BYTBITS) & BYTMASK)
#define B2(c) (((c)>>(2*BYTBITS)) & BYTMASK)
#define B3(c) (((c)>>(3*BYTBITS)) & BYTMASK)
#if NBYTS == 1
#define GETCOLOR(cm, c) ((cm)->tree->tcolor[B0(c)])
#endif
/* beware, for NBYTS>1, GETCOLOR() is unsafe -- 2nd arg used repeatedly */
#if NBYTS == 2
#define GETCOLOR(cm, c) ((cm)->tree->tptr[B1(c)]->tcolor[B0(c)])
#endif
#if NBYTS == 4
#define GETCOLOR(cm, c) ((cm)->tree->tptr[B3(c)]->tptr[B2(c)]->tptr[B1(c)]->tcolor[B0(c)])
#endif
/*
* Interface definitions for locale-interface functions in locale.c.
* Multi-character collating elements (MCCEs) cause most of the trouble.
*/
struct cvec {
int nchrs; /* number of chrs */
int chrspace; /* number of chrs possible */
chr *chrs; /* pointer to vector of chrs */
int nranges; /* number of ranges (chr pairs) */
int rangespace; /* number of chrs possible */
chr *ranges; /* pointer to vector of chr pairs */
int nmcces; /* number of MCCEs */
int mccespace; /* number of MCCEs possible */
int nmccechrs; /* number of chrs used for MCCEs */
chr *mcces[1]; /* pointers to 0-terminated MCCEs */
/* and both batches of chrs are on the end */
};
/* caution: this value cannot be changed easily */
#define MAXMCCE 2 /* length of longest MCCE */
/*
* definitions for NFA internal representation
*
* Having a "from" pointer within each arc may seem redundant, but it
* saves a lot of hassle.
*/
struct state;
struct arc {
int type;
# define ARCFREE '\0'
color co;
struct state *from; /* where it's from (and contained within) */
struct state *to; /* where it's to */
struct arc *outchain; /* *from's outs chain or free chain */
# define freechain outchain
struct arc *inchain; /* *to's ins chain */
struct arc *colorchain; /* color's arc chain */
};
struct arcbatch { /* for bulk allocation of arcs */
struct arcbatch *next;
# define ABSIZE 10
struct arc a[ABSIZE];
};
struct state {
int no;
# define FREESTATE (-1)
char flag; /* marks special states */
int nins; /* number of inarcs */
struct arc *ins; /* chain of inarcs */
int nouts; /* number of outarcs */
struct arc *outs; /* chain of outarcs */
struct arc *free; /* chain of free arcs */
struct state *tmp; /* temporary for traversal algorithms */
struct state *next; /* chain for traversing all */
struct state *prev; /* back chain */
struct arcbatch oas; /* first arcbatch, avoid malloc in easy case */
int noas; /* number of arcs used in first arcbatch */
};
struct nfa {
struct state *pre; /* pre-initial state */
struct state *init; /* initial state */
struct state *final; /* final state */
struct state *post; /* post-final state */
int nstates; /* for numbering states */
struct state *states; /* state-chain header */
struct state *slast; /* tail of the chain */
struct state *free; /* free list */
struct colormap *cm; /* the color map */
color bos[2]; /* colors, if any, assigned to BOS and BOL */
color eos[2]; /* colors, if any, assigned to EOS and EOL */
struct vars *v; /* simplifies compile error reporting */
struct nfa *parent; /* parent NFA, if any */
};
/*
* definitions for compacted NFA
*/
struct carc {
color co; /* COLORLESS is list terminator */
int to; /* state number */
};
struct cnfa {
int nstates; /* number of states */
int ncolors; /* number of colors */
int flags;
# define HASLACONS 01 /* uses lookahead constraints */
int pre; /* setup state number */
int post; /* teardown state number */
color bos[2]; /* colors, if any, assigned to BOS and BOL */
color eos[2]; /* colors, if any, assigned to EOS and EOL */
struct carc **states; /* vector of pointers to outarc lists */
struct carc *arcs; /* the area for the lists */
};
#define ZAPCNFA(cnfa) ((cnfa).nstates = 0)
#define NULLCNFA(cnfa) ((cnfa).nstates == 0)
/*
* subexpression tree
*/
struct subre {
char op; /* '|', '.' (concat), 'b' (backref), '(', '=' */
char flags;
# define LONGER 01 /* prefers longer match */
# define SHORTER 02 /* prefers shorter match */
# define MIXED 04 /* mixed preference below */
# define CAP 010 /* capturing parens below */
# define BACKR 020 /* back reference below */
# define INUSE 0100 /* in use in final tree */
# define LOCAL 03 /* bits which may not propagate up */
# define LMIX(f) ((f)<<2) /* LONGER -> MIXED */
# define SMIX(f) ((f)<<1) /* SHORTER -> MIXED */
# define UP(f) (((f)&~LOCAL) | (LMIX(f) & SMIX(f) & MIXED))
# define MESSY(f) ((f)&(MIXED|CAP|BACKR))
# define PREF(f) ((f)&LOCAL)
# define PREF2(f1, f2) ((PREF(f1) != 0) ? PREF(f1) : PREF(f2))
# define COMBINE(f1, f2) (UP((f1)|(f2)) | PREF2(f1, f2))
short retry; /* index into retry memory */
int subno; /* subexpression number (for 'b' and '(') */
short min; /* min repetitions, for backref only */
short max; /* max repetitions, for backref only */
struct subre *left; /* left child, if any (also freelist chain) */
struct subre *right; /* right child, if any */
struct state *begin; /* outarcs from here... */
struct state *end; /* ...ending in inarcs here */
struct cnfa cnfa; /* compacted NFA, if any */
struct subre *chain; /* for bookkeeping and error cleanup */
};
/*
* table of function pointers for generic manipulation functions
* A regex_t's re_fns points to one of these.
*/
struct fns {
void FUNCPTR(free, (regex_t *));
};
/*
* the insides of a regex_t, hidden behind a void *
*/
struct guts {
int magic;
# define GUTSMAGIC 0xfed9
int cflags; /* copy of compile flags */
long info; /* copy of re_info */
size_t nsub; /* copy of re_nsub */
struct subre *tree;
struct cnfa search; /* for fast preliminary search */
int ntree;
struct colormap cmap;
int FUNCPTR(compare, (const chr *, const chr *, size_t));
struct subre *lacons; /* lookahead-constraint vector */
int nlacons; /* size of lacons */
};
src/include/regex/utils.h deleted 100644 → 0
View file @ 32c3db0f
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)utils.h 8.3 (Berkeley) 3/20/94
*/
#ifndef _REGEX_UTILS_H
#define _REGEX_UTILS_H
#include <limits.h>
/* utility definitions */
#define DUPMAX 100000000 /* xxx is this right? */
#define INFINITY (DUPMAX + 1)
#define NC (SHRT_MAX - SHRT_MIN + 1)
typedef unsigned char uch;
/* switch off assertions (if not already off) if no REDEBUG */
#ifndef REDEBUG
#ifndef NDEBUG
#define NDEBUG /* no assertions please */
#endif
#endif
#endif /* _REGEX_UTILS_H */
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