Clean up the INET-vs-CIDR situation. Get rid of the internal is_cidr flag

and rely exclusively on the SQL type system to tell the difference between
the types.  Prevent creation of invalid CIDR values via casting from INET
or set_masklen() --- both of these operations now silently zero any bits
to the right of the netmask.  Remove duplicate CIDR comparison operators,
letting the type rely on the INET operators instead.

doc/src/sgml/func.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.302 2006/01/11 20:12:38 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.303 2006/01/26 02:35:48 tgl Exp $
 PostgreSQL documentation
 -->
 
@@ -6797,9 +6797,7 @@ SELECT pg_sleep(1.5);
    types.  The <function>host</function>,
    <function>text</function>, and <function>abbrev</function>
    functions are primarily intended to offer alternative display
-   formats. You can cast a text value to <type>inet</> using normal casting
-   syntax: <literal>inet(<replaceable>expression</>)</literal> or
-   <literal><replaceable>colname</>::inet</literal>.
+   formats.
   </para>
 
     <table id="cidr-inet-functions-table">
@@ -6843,6 +6841,13 @@ SELECT pg_sleep(1.5);
         <entry><literal>set_masklen('192.168.1.5/24', 16)</literal></entry>
         <entry><literal>192.168.1.5/16</literal></entry>
        </row>
+       <row>
+        <entry><literal><function>set_masklen</function>(<type>cidr</type>, <type>int</type>)</literal></entry>
+        <entry><type>cidr</type></entry>
+        <entry>set netmask length for <type>cidr</type> value</entry>
+        <entry><literal>set_masklen('192.168.1.0/24'::cidr, 16)</literal></entry>
+        <entry><literal>192.168.0.0/16</literal></entry>
+       </row>
        <row>
         <entry><literal><function>netmask</function>(<type>inet</type>)</literal></entry>
         <entry><type>inet</type></entry>
@@ -6875,6 +6880,13 @@ SELECT pg_sleep(1.5);
         <entry><literal><function>abbrev</function>(<type>inet</type>)</literal></entry>
         <entry><type>text</type></entry>
         <entry>abbreviated display format as text</entry>
+        <entry><literal>abbrev(inet '10.1.0.0/16')</literal></entry>
+        <entry><literal>10.1.0.0/16</literal></entry>
+       </row>
+       <row>
+        <entry><literal><function>abbrev</function>(<type>cidr</type>)</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>abbreviated display format as text</entry>
         <entry><literal>abbrev(cidr '10.1.0.0/16')</literal></entry>
         <entry><literal>10.1/16</literal></entry>
        </row>
@@ -6890,6 +6902,22 @@ SELECT pg_sleep(1.5);
      </tgroup>
     </table>
 
+  <para>
+   Any <type>cidr</> value can be cast to <type>inet</> implicitly
+   or explicitly; therefore, the functions shown above as operating on
+   <type>inet</> also work on <type>cidr</> values.  (Where there are
+   separate functions for <type>inet</> and <type>cidr</>, it is because
+   the behavior should be different for the two cases.)
+   Also, it is permitted to cast an <type>inet</> value to <type>cidr</>.
+   When this is done, any bits to the right of the netmask are silently zeroed
+   to create a valid <type>cidr</> value.
+   In addition,
+   you can cast a text value to <type>inet</> or <type>cidr</>
+   using normal casting syntax: for example,
+   <literal>inet(<replaceable>expression</>)</literal> or
+   <literal><replaceable>colname</>::cidr</literal>.
+  </para>
+
   <para>
    <xref linkend="macaddr-functions-table"> shows the functions
    available for use with the <type>macaddr</type> type.  The function

src/backend/optimizer/path/indxpath.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.197 2006/01/25 20:29:23 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.198 2006/01/26 02:35:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2024,8 +2024,6 @@ match_special_index_operator(Expr *clause, Oid opclass,
 
 		case OID_INET_SUB_OP:
 		case OID_INET_SUBEQ_OP:
-		case OID_CIDR_SUB_OP:
-		case OID_CIDR_SUBEQ_OP:
 			isIndexable = true;
 			break;
 	}
@@ -2087,12 +2085,8 @@ match_special_index_operator(Expr *clause, Oid opclass,
 
 		case OID_INET_SUB_OP:
 		case OID_INET_SUBEQ_OP:
-			isIndexable = (opclass == INET_BTREE_OPS_OID);
-			break;
-
-		case OID_CIDR_SUB_OP:
-		case OID_CIDR_SUBEQ_OP:
-			isIndexable = (opclass == CIDR_BTREE_OPS_OID);
+			isIndexable = (opclass == INET_BTREE_OPS_OID ||
+						   opclass == CIDR_BTREE_OPS_OID);
 			break;
 	}
 
@@ -2317,8 +2311,6 @@ expand_indexqual_opclause(RestrictInfo *rinfo, Oid opclass)
 
 		case OID_INET_SUB_OP:
 		case OID_INET_SUBEQ_OP:
-		case OID_CIDR_SUB_OP:
-		case OID_CIDR_SUBEQ_OP:
 			result = network_prefix_quals(leftop, expr_op, opclass,
 										  patt->constvalue);
 			break;
@@ -2681,14 +2673,6 @@ network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass, Datum rightop)
 			datatype = INETOID;
 			is_eq = true;
 			break;
-		case OID_CIDR_SUB_OP:
-			datatype = CIDROID;
-			is_eq = false;
-			break;
-		case OID_CIDR_SUBEQ_OP:
-			datatype = CIDROID;
-			is_eq = true;
-			break;
 		default:
 			elog(ERROR, "unexpected operator: %u", expr_op);
 			return NIL;

src/include/catalog/catversion.h

@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.312 2006/01/18 06:49:27 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.313 2006/01/26 02:35:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200601181
+#define CATALOG_VERSION_NO	200601251
 
 #endif

src/include/catalog/pg_amop.h

@@ -23,7 +23,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_amop.h,v 1.67 2005/11/07 17:36:46 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_amop.h,v 1.68 2006/01/26 02:35:49 tgl Exp $
  *
  * NOTES
  *	 the genbki.sh script reads this file and generates .bki
@@ -388,11 +388,11 @@ DATA(insert (	1974	0 5 f 1205 ));
  *	btree cidr
  */
 
-DATA(insert (	 432	0 1 f  822 ));
-DATA(insert (	 432	0 2 f  823 ));
-DATA(insert (	 432	0 3 f  820 ));
-DATA(insert (	 432	0 4 f  825 ));
-DATA(insert (	 432	0 5 f  824 ));
+DATA(insert (	 432	0 1 f 1203 ));
+DATA(insert (	 432	0 2 f 1204 ));
+DATA(insert (	 432	0 3 f 1201 ));
+DATA(insert (	 432	0 4 f 1206 ));
+DATA(insert (	 432	0 5 f 1205 ));
 
 /*
  *	btree numeric
@@ -523,7 +523,7 @@ DATA(insert (	 427	0 1 f 1054 ));
 /* char_ops */
 DATA(insert (	 431	0 1 f	92 ));
 /* cidr_ops */
-DATA(insert (	 433	0 1 f  820 ));
+DATA(insert (	 433	0 1 f 1201 ));
 /* date_ops */
 DATA(insert (	 435	0 1 f 1093 ));
 /* float4_ops */

src/include/catalog/pg_cast.h

@@ -10,7 +10,7 @@
  *
  * Copyright (c) 2002-2005, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_cast.h,v 1.24 2005/10/21 15:45:06 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_cast.h,v 1.25 2006/01/26 02:35:49 tgl Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
@@ -249,7 +249,7 @@ DATA(insert (  718	604 1544 e ));
  * INET category
  */
 DATA(insert (  650	869    0 i ));
-DATA(insert (  869	650    0 i ));
+DATA(insert (  869	650 1715 a ));
 
 /*
  * BitString category

src/include/catalog/pg_operator.h

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_operator.h,v 1.137 2005/10/15 02:49:42 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_operator.h,v 1.138 2006/01/26 02:35:49 tgl Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
@@ -637,7 +637,7 @@ DATA(insert OID = 1223 (  "<="	   PGNSP PGUID b f 829 829	 16 1225 1224	 0	  0
 DATA(insert OID = 1224 (  ">"	   PGNSP PGUID b f 829 829	 16 1222 1223	 0	  0   0   0 macaddr_gt scalargtsel scalargtjoinsel ));
 DATA(insert OID = 1225 (  ">="	   PGNSP PGUID b f 829 829	 16 1223 1222	 0	  0   0   0 macaddr_ge scalargtsel scalargtjoinsel ));
 
-/* INET type */
+/* INET type (these also support CIDR via implicit cast) */
 DATA(insert OID = 1201 (  "="	   PGNSP PGUID b t 869 869	 16 1201 1202 1203 1203 1203 1205 network_eq eqsel eqjoinsel ));
 DATA(insert OID = 1202 (  "<>"	   PGNSP PGUID b f 869 869	 16 1202 1201	 0	  0   0   0 network_ne neqsel neqjoinsel ));
 DATA(insert OID = 1203 (  "<"	   PGNSP PGUID b f 869 869	 16 1205 1206	 0	  0   0   0 network_lt scalarltsel scalarltjoinsel ));
@@ -653,22 +653,6 @@ DATA(insert OID = 933  (  ">>"	   PGNSP PGUID b f 869 869	 16 931		0	 0	  0   0
 DATA(insert OID = 934  (  ">>="    PGNSP PGUID b f 869 869	 16 932		0	 0	  0   0   0 network_supeq - - ));
 #define OID_INET_SUPEQ_OP				934
 
-/* CIDR type */
-DATA(insert OID = 820 (  "="	   PGNSP PGUID b t 650 650	 16 820 821 822 822 822 824 network_eq eqsel eqjoinsel ));
-DATA(insert OID = 821 (  "<>"	   PGNSP PGUID b f 650 650	 16 821 820   0   0   0   0 network_ne neqsel neqjoinsel ));
-DATA(insert OID = 822 (  "<"	   PGNSP PGUID b f 650 650	 16 824 825   0   0   0   0 network_lt scalarltsel scalarltjoinsel ));
-DATA(insert OID = 823 (  "<="	   PGNSP PGUID b f 650 650	 16 825 824   0   0   0   0 network_le scalarltsel scalarltjoinsel ));
-DATA(insert OID = 824 (  ">"	   PGNSP PGUID b f 650 650	 16 822 823   0   0   0   0 network_gt scalargtsel scalargtjoinsel ));
-DATA(insert OID = 825 (  ">="	   PGNSP PGUID b f 650 650	 16 823 822   0   0   0   0 network_ge scalargtsel scalargtjoinsel ));
-DATA(insert OID = 826 (  "<<"	   PGNSP PGUID b f 650 650	 16 828   0   0   0   0   0 network_sub - - ));
-#define OID_CIDR_SUB_OP		826
-DATA(insert OID = 827 (  "<<="	   PGNSP PGUID b f 650 650	 16 1004  0   0   0   0   0 network_subeq - - ));
-#define OID_CIDR_SUBEQ_OP	827
-DATA(insert OID = 828 (  ">>"	   PGNSP PGUID b f 650 650	 16 826   0   0   0   0   0 network_sup - - ));
-#define OID_CIDR_SUP_OP		828
-DATA(insert OID = 1004 ( ">>="	   PGNSP PGUID b f 650 650	 16 827   0   0   0   0   0 network_supeq - - ));
-#define OID_CIDR_SUPEQ_OP	1004
-
 /* case-insensitive LIKE hacks */
 DATA(insert OID = 1625 (  "~~*"   PGNSP PGUID b f  19	25	16 0 1626 0 0 0 0 nameiclike iclikesel iclikejoinsel ));
 #define OID_NAME_ICLIKE_OP		1625

src/include/catalog/pg_proc.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.392 2006/01/18 06:49:28 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.393 2006/01/26 02:35:49 tgl Exp $
  *
  * NOTES
  *	  The script catalog/genbki.sh reads this file and generates .bki
@@ -2391,10 +2391,16 @@ DATA(insert OID = 930 (  network_supeq		PGNSP PGUID 12 f f t f i 2 16 "869 869"
 DESCR("is-supernet-or-equal");
 
 /* inet/cidr functions */
-DATA(insert OID = 605 (  abbrev				PGNSP PGUID 12 f f t f i 1 25 "869" _null_ _null_ _null_	network_abbrev - _null_ ));
-DESCR("abbreviated display of inet/cidr value");
+DATA(insert OID = 598 (  abbrev				PGNSP PGUID 12 f f t f i 1 25 "869" _null_ _null_ _null_	inet_abbrev - _null_ ));
+DESCR("abbreviated display of inet value");
+DATA(insert OID = 599 (  abbrev				PGNSP PGUID 12 f f t f i 1 25 "650" _null_ _null_ _null_	cidr_abbrev - _null_ ));
+DESCR("abbreviated display of cidr value");
+DATA(insert OID = 605 (  set_masklen		PGNSP PGUID 12 f f t f i 2 869 "869 23" _null_ _null_ _null_	inet_set_masklen - _null_ ));
+DESCR("change netmask of inet");
+DATA(insert OID = 635 (  set_masklen		PGNSP PGUID 12 f f t f i 2 650 "650 23" _null_ _null_ _null_	cidr_set_masklen - _null_ ));
+DESCR("change netmask of cidr");
 DATA(insert OID = 711 (  family				PGNSP PGUID 12 f f t f i 1 23 "869" _null_ _null_ _null_	network_family - _null_ ));
-DESCR("return address family (4 for IPv4, 6 for IPv6)");
+DESCR("address family (4 for IPv4, 6 for IPv6)");
 DATA(insert OID = 683 (  network			PGNSP PGUID 12 f f t f i 1 650 "869" _null_ _null_ _null_ network_network - _null_ ));
 DESCR("network part of address");
 DATA(insert OID = 696 (  netmask			PGNSP PGUID 12 f f t f i 1 869 "869" _null_ _null_ _null_ network_netmask - _null_ ));
@@ -2413,8 +2419,8 @@ DATA(insert OID = 1713 (  inet				PGNSP PGUID 12 f f t f i 1 869 "25" _null_ _nu
 DESCR("text to inet");
 DATA(insert OID = 1714 (  cidr				PGNSP PGUID 12 f f t f i 1 650 "25" _null_ _null_ _null_	text_cidr - _null_ ));
 DESCR("text to cidr");
-DATA(insert OID = 1715 (  set_masklen		PGNSP PGUID 12 f f t f i 2 869 "869 23" _null_ _null_ _null_	inet_set_masklen - _null_ ));
-DESCR("change the netmask of an inet");
+DATA(insert OID = 1715 (  cidr				PGNSP PGUID 12 f f t f i 1 650 "869" _null_ _null_ _null_	inet_to_cidr - _null_ ));
+DESCR("coerce inet to cidr");
 
 DATA(insert OID = 2196 (  inet_client_addr		PGNSP PGUID 12 f f f f s 0 869 "" _null_ _null_ _null_	inet_client_addr - _null_ ));
 DESCR("INET address of the client");

src/include/utils/builtins.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.271 2006/01/18 06:49:29 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.272 2006/01/26 02:35:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -720,11 +720,14 @@ extern Datum network_family(PG_FUNCTION_ARGS);
 extern Datum network_broadcast(PG_FUNCTION_ARGS);
 extern Datum network_host(PG_FUNCTION_ARGS);
 extern Datum network_show(PG_FUNCTION_ARGS);
-extern Datum network_abbrev(PG_FUNCTION_ARGS);
+extern Datum inet_abbrev(PG_FUNCTION_ARGS);
+extern Datum cidr_abbrev(PG_FUNCTION_ARGS);
 extern double convert_network_to_scalar(Datum value, Oid typid);
 extern Datum text_cidr(PG_FUNCTION_ARGS);
 extern Datum text_inet(PG_FUNCTION_ARGS);
+extern Datum inet_to_cidr(PG_FUNCTION_ARGS);
 extern Datum inet_set_masklen(PG_FUNCTION_ARGS);
+extern Datum cidr_set_masklen(PG_FUNCTION_ARGS);
 extern Datum network_scan_first(Datum in);
 extern Datum network_scan_last(Datum in);
 extern Datum inet_client_addr(PG_FUNCTION_ARGS);

src/include/utils/inet.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/inet.h,v 1.21 2006/01/23 21:45:47 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/utils/inet.h,v 1.22 2006/01/26 02:35:51 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -22,7 +22,6 @@ typedef struct
 {
 	unsigned char family;		/* PGSQL_AF_INET or PGSQL_AF_INET6 */
 	unsigned char bits;			/* number of bits in netmask */
-	bool is_cidr;				/* is cidr? */
 	unsigned char ipaddr[16];	/* up to 128 bits of address */
 } inet_struct;
 

src/test/regress/expected/opr_sanity.out

@@ -274,6 +274,8 @@ WHERE c.castfunc = p.oid AND
 -- also binary compatible.  This is legal, but usually not intended.
 -- As of 7.4, this finds the casts from text and varchar to bpchar, because
 -- those are binary-compatible while the reverse way goes through rtrim().
+-- As of 8.2, this finds the cast from cidr to inet, because that is a
+-- trivial binary coercion while the other way goes through inet_to_cidr().
 SELECT *
 FROM pg_cast c
 WHERE c.castfunc = 0 AND
@@ -285,7 +287,8 @@ WHERE c.castfunc = 0 AND
 ------------+------------+----------+-------------
          25 |       1042 |        0 | i
        1043 |       1042 |        0 | i
-(2 rows)
+        650 |        869 |        0 | i
+(3 rows)
 
 -- **************** pg_operator ****************
 -- Look for illegal values in pg_operator fields.

src/test/regress/sql/opr_sanity.sql

@@ -223,6 +223,9 @@ WHERE c.castfunc = p.oid AND
 -- As of 7.4, this finds the casts from text and varchar to bpchar, because
 -- those are binary-compatible while the reverse way goes through rtrim().
 
+-- As of 8.2, this finds the cast from cidr to inet, because that is a
+-- trivial binary coercion while the other way goes through inet_to_cidr().
+
 SELECT *
 FROM pg_cast c
 WHERE c.castfunc = 0 AND