As proposed, here is the current version of PL/pgSQL. The

    test isn't that complete up to now,  but  I  think  it  shows
    enough of the capabilities of the module.

    The  Makefile  assumes  it  is  located  in a directory under
    pgsql/src/pl.   Since   it   includes   Makefile.global   and
    Makefile.port  and doesn't use any own compiler/linker calls,
    it should build on most of our supported  platforms  (I  only
    tested  under Linux up to now).  It requires flex and bison I
    think. Maybe we should ship prepared gram.c etc. like for the
    main parser too?


Jan

contrib/README

@@ -58,6 +58,10 @@ mSQL-interface -
 noupdate -
 	trigger to prevent updates on single columns
 
+plpgsql - 
+	Postgres procedural language
+	by Jan Wieck <jwieck@debis.com>
+
 pginterface -
 	A crude C/4GL
 	by Bruce Momjian <root@candle.pha.pa.us>

contrib/plpgsql/src/INSTALL

+Installation of PL/pgSQL
+
+
+1)	Type 'make' to build the shared plpgsql object.
+
+2)	Type 'make install' to install the shared object in
+	the PostgreSQL library directory.
+
+3)	Declare the PL/pgSQL procedural language in your
+	database by
+
+		psql dbname <mklang.sql
+
+	If the PostgreSQL library directory is different from
+	/usr/local/pgsql/lib you must edit mklang.sql prior.
+
+	If you declare the language in the template1 database,
+	any subsequently created database will have PL/pgSQL
+	support installed automatically.
+
+
+

contrib/plpgsql/src/mklang.sql

+--
+-- PL/pgSQL language declaration
+--
+-- $Header: /cvsroot/pgsql/contrib/plpgsql/src/Attic/mklang.sql,v 1.1 1998/08/22 12:38:31 momjian Exp $
+--
+
+create function plpgsql_call_handler() returns opaque
+	as '/usr/local/pgsql/lib/plpgsql.so'
+	language 'C';
+
+create trusted procedural language 'plpgsql'
+	handler plpgsql_call_handler
+	lancompiler 'PL/pgSQL';
+

contrib/plpgsql/src/pl_handler.c

+/**********************************************************************
+ * pl_handler.c		- Handler for the PL/pgSQL
+ *			  procedural language
+ *
+ * IDENTIFICATION
+ *    $Header: /cvsroot/pgsql/contrib/plpgsql/src/Attic/pl_handler.c,v 1.1 1998/08/22 12:38:32 momjian Exp $
+ *
+ *    This software is copyrighted by Jan Wieck - Hamburg.
+ *
+ *    The author hereby grants 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
+ *    author  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 AUTHOR 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  AUTHOR  HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ *    DAMAGE.
+ *
+ *    THE  AUTHOR  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 AUTHOR  AND  DISTRIBUTORS  HAVE  NO
+ *    OBLIGATION   TO   PROVIDE   MAINTENANCE,   SUPPORT,  UPDATES,
+ *    ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ **********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include "plpgsql.h"
+#include "pl.tab.h"
+
+#include "executor/spi.h"
+#include "commands/trigger.h"
+#include "utils/elog.h"
+#include "utils/builtins.h"
+#include "fmgr.h"
+#include "access/heapam.h"
+
+#include "utils/syscache.h"
+#include "catalog/pg_proc.h"
+#include "catalog/pg_type.h"
+
+
+static	PLpgSQL_function	*compiled_functions = NULL;
+
+
+Datum plpgsql_call_handler(FmgrInfo *proinfo,
+	FmgrValues *proargs, bool *isNull);
+
+static Datum plpgsql_func_handler(FmgrInfo *proinfo,
+	FmgrValues *proargs, bool *isNull);
+
+static HeapTuple plpgsql_trigger_handler(FmgrInfo *proinfo);
+
+
+/* ----------
+ * plpgsql_call_handler		- This is the only visible function
+ *				  of the PL interpreter. The PostgreSQL
+ *				  function manager and trigger manager
+ *				  call this function for execution of
+ *				  PL/pgSQL procedures.
+ * ----------
+ */
+Datum
+plpgsql_call_handler(FmgrInfo	*proinfo,
+		FmgrValues	*proargs,
+		bool		*isNull)
+{
+    Datum	retval;
+
+    /* ----------
+     * Connect to SPI manager
+     * ----------
+     */
+    if (SPI_connect() != SPI_OK_CONNECT) {
+        elog(ERROR, "plpgsql: cannot connect to SPI manager");
+    }
+
+    /* ----------
+     * Determine if called as function or trigger and
+     * call appropriate subhandler
+     * ----------
+     */
+    if (CurrentTriggerData == NULL) {
+	retval =  plpgsql_func_handler(proinfo, proargs, isNull);
+    } else {
+	retval =  (Datum)plpgsql_trigger_handler(proinfo);
+    }
+
+    /* ----------
+     * Disconnect from SPI manager
+     * ----------
+     */
+    if (SPI_finish() != SPI_OK_FINISH) {
+        elog(ERROR, "plpgsql: SPI_finish() failed");
+    }
+
+    return retval;
+}
+
+
+/* ----------
+ * plpgsql_func_handler()	- Handler for regular function calls
+ * ----------
+ */
+static Datum
+plpgsql_func_handler(FmgrInfo	*proinfo,
+		FmgrValues	*proargs,
+		bool		*isNull)
+{
+    PLpgSQL_function	*func;
+
+    /* ----------
+     * Check if we already compiled this function
+     * ----------
+     */
+    for (func = compiled_functions; func != NULL; func = func->next) {
+        if (proinfo->fn_oid == func->fn_oid)
+	    break;
+    }
+
+    /* ----------
+     * If not, do so and add it to the compiled ones
+     * ----------
+     */
+    if (func == NULL) {
+	func = plpgsql_compile(proinfo->fn_oid, T_FUNCTION);
+
+	func->next = compiled_functions;
+	compiled_functions = func;
+    }
+
+    return plpgsql_exec_function(func, proargs, isNull);
+}
+
+
+/* ----------
+ * plpgsql_trigger_handler()	- Handler for trigger calls
+ * ----------
+ */
+static HeapTuple
+plpgsql_trigger_handler(FmgrInfo *proinfo)
+{
+    TriggerData		*trigdata;
+    PLpgSQL_function	*func;
+
+    /* ----------
+     * Save the current trigger data local
+     * ----------
+     */
+    trigdata = CurrentTriggerData;
+    CurrentTriggerData = NULL;
+
+    /* ----------
+     * Check if we already compiled this trigger procedure
+     * ----------
+     */
+    for (func = compiled_functions; func != NULL; func = func->next) {
+        if (proinfo->fn_oid == func->fn_oid)
+	    break;
+    }
+
+    /* ----------
+     * If not, do so and add it to the compiled ones
+     * ----------
+     */
+    if (func == NULL) {
+	func = plpgsql_compile(proinfo->fn_oid, T_TRIGGER);
+
+	func->next = compiled_functions;
+	compiled_functions = func;
+    }
+
+    return plpgsql_exec_trigger(func, trigdata);
+}
+
+

contrib/plpgsql/src/scan.l

+%{
+/**********************************************************************
+ * scan.l		- Scanner for the PL/pgSQL
+ *			  procedural language
+ *
+ * IDENTIFICATION
+ *    $Header: /cvsroot/pgsql/contrib/plpgsql/src/Attic/scan.l,v 1.1 1998/08/22 12:38:33 momjian Exp $
+ *
+ *    This software is copyrighted by Jan Wieck - Hamburg.
+ *
+ *    The author hereby grants 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
+ *    author  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 AUTHOR 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  AUTHOR  HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ *    DAMAGE.
+ *
+ *    THE  AUTHOR  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 AUTHOR  AND  DISTRIBUTORS  HAVE  NO
+ *    OBLIGATION   TO   PROVIDE   MAINTENANCE,   SUPPORT,  UPDATES,
+ *    ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ **********************************************************************/
+
+static char	*plpgsql_source;
+static int	plpgsql_bytes_left;
+static int	scanner_functype;
+static int	scanner_typereported;
+int	plpgsql_SpaceScanned = 0;
+
+static void plpgsql_input(char *buf, int *result, int max);
+#define YY_INPUT(buf,res,max)	plpgsql_input(buf, &res, max)
+%}
+
+WS	[[:alpha:]_]
+WC	[[:alnum:]_]
+
+%x	IN_STRING IN_COMMENT
+
+%%
+    /* ----------
+     * Local variable in scanner to remember where
+     * a string or comment started
+     * ----------
+     */
+    int	start_lineno = 0;
+
+    /* ----------
+     * Reset the state when entering the scanner
+     * ----------
+     */
+    BEGIN INITIAL;
+    plpgsql_SpaceScanned = 0;
+
+    /* ----------
+     * On the first call to a new source report the
+     * functions type (T_FUNCTION or T_TRIGGER)
+     * ----------
+     */
+    if (!scanner_typereported) {
+        scanner_typereported = 1;
+	return scanner_functype;
+    }
+
+    /* ----------
+     * The keyword rules
+     * ----------
+     */
+:=			{ return K_ASSIGN;			}
+=			{ return K_ASSIGN;			}
+\.\.			{ return K_DOTDOT;			}
+alias			{ return K_ALIAS;			}
+begin			{ return K_BEGIN;			}
+bpchar			{ return T_BPCHAR;			}
+char			{ return T_CHAR;			}
+constant		{ return K_CONSTANT;			}
+debug			{ return K_DEBUG;			}
+declare			{ return K_DECLARE;			}
+default			{ return K_DEFAULT;			}
+else			{ return K_ELSE;			}
+end			{ return K_END;				}
+exception		{ return K_EXCEPTION;			}
+exit			{ return K_EXIT;			}
+for			{ return K_FOR;				}
+from			{ return K_FROM;			}
+if			{ return K_IF;				}
+in			{ return K_IN;				}
+into			{ return K_INTO;			}
+loop			{ return K_LOOP;			}
+not			{ return K_NOT;				}
+notice			{ return K_NOTICE;			}
+null			{ return K_NULL;			}
+perform			{ return K_PERFORM;			}
+raise			{ return K_RAISE;			}
+record			{ return K_RECORD;			}
+rename			{ return K_RENAME;			}
+return			{ return K_RETURN;			}
+reverse			{ return K_REVERSE;			}
+select			{ return K_SELECT;			}
+then			{ return K_THEN;			}
+to			{ return K_TO;				}
+type			{ return K_TYPE;			}
+varchar			{ return T_VARCHAR;			}
+when			{ return K_WHEN;			}
+while			{ return K_WHILE;			}
+
+^#option		{ return O_OPTION;			}
+dump			{ return O_DUMP;			}
+
+
+    /* ----------
+     * Special word rules
+     * ----------
+     */
+{WS}{WC}*		{ return plpgsql_parse_word(yytext);	}
+{WS}{WC}*\.{WS}{WC}*	{ return plpgsql_parse_dblword(yytext);	}
+{WS}{WC}*\.{WS}{WC}*\.{WS}{WC}*	{ return plpgsql_parse_tripword(yytext); }
+{WS}{WC}*%TYPE		{ return plpgsql_parse_wordtype(yytext);	}
+{WS}{WC}*\.{WS}{WC}*%TYPE	{ return plpgsql_parse_dblwordtype(yytext); }
+{WS}{WC}*%ROWTYPE	{ return plpgsql_parse_wordrowtype(yytext);	}
+
+\$[0-9]+		{ return plpgsql_parse_word(yytext);	}
+[0-9]+			{ return T_NUMBER;			}
+
+    /* ----------
+     * Ignore whitespaces but remember this happened
+     * ----------
+     */
+[ \t\n]+		{ plpgsql_SpaceScanned = 1;		}
+
+    /* ----------
+     * Eat up comments
+     * ----------
+     */
+--[^\n]*		;
+\/\*			{ start_lineno = yylineno;
+			  BEGIN IN_COMMENT;
+			}
+<IN_COMMENT>\*\/	{ BEGIN INITIAL;			}
+<IN_COMMENT>\n		;
+<IN_COMMENT>.		;
+<IN_COMMENT><<EOF>>	{ plpgsql_comperrinfo();
+			  elog(ERROR, "unterminated comment starting on line %d",
+				start_lineno);
+			}
+
+    /* ----------
+     * Collect anything inside of ''s and return one STRING
+     * ----------
+     */
+'			{ start_lineno = yylineno;
+			  BEGIN IN_STRING;
+			  yymore();
+			}
+<IN_STRING>\\.		|
+<IN_STRING>''		{ yymore();				}
+<IN_STRING>'		{ BEGIN INITIAL;
+			  return T_STRING;
+			}
+<IN_STRING><<EOF>>	{ plpgsql_comperrinfo();
+			  elog(ERROR, "unterminated string starting on line %d", 
+				start_lineno);
+			}
+<IN_STRING>[^'\\]*	{ yymore();				}
+
+    /* ----------
+     * Any unmatched character is returned as is
+     * ----------
+     */
+.			{ return yytext[0];			}
+
+%%
+
+int yywrap()
+{
+    return 1;
+}
+
+
+static void plpgsql_input(char *buf, int *result, int max)
+{
+    int n = max;
+    if (n > plpgsql_bytes_left) {
+        n = plpgsql_bytes_left;
+    }
+
+    if (n == 0) {
+        *result = YY_NULL;
+	return;
+    }
+
+    *result = n;
+    memcpy(buf, plpgsql_source, n);
+    plpgsql_source += n;
+    plpgsql_bytes_left -= n;
+}
+
+
+void plpgsql_setinput(char *source, int functype)
+{
+    yyrestart(NULL);
+    yylineno = 1;
+
+    plpgsql_source = source;
+    if (*plpgsql_source == '\n')
+        plpgsql_source++;
+    plpgsql_bytes_left = strlen(plpgsql_source);
+
+    scanner_functype     = functype;
+    scanner_typereported = 0;
+}
+
+

contrib/plpgsql/test/README

+Test suite for PL/pgSQL
+
+Scenario:
+
+    A building with a modern TP cabel installation where any
+    of the wall connectors can be used to plug in phones,
+    ethernet interfaces or local office hubs. The backside
+    of the wall connectors is wired to one of several patch-
+    fields in the building.
+
+    In the patchfields, there are hubs and all the slots
+    representing the wall connectors. In addition there are
+    slots that can represent a phone line from the central
+    phone system.
+
+    Triggers ensure consistency of the patching information.
+
+    Functions are used to build up powerful views that let
+    you look behind the wall when looking at a patchfield
+    or into a room.
+
+

contrib/plpgsql/test/expected/tables.out

+QUERY: create table Room (
+    roomno	char(8),
+    comment	text
+);
+QUERY: create unique index Room_rno on Room using btree (roomno bpchar_ops);
+QUERY: create table WSlot (
+    slotname	char(20),
+    roomno	char(8),
+    slotlink	char(20),
+    backlink	char(20)
+);
+QUERY: create unique index WSlot_name on WSlot using btree (slotname bpchar_ops);
+QUERY: create table PField (
+    name	text,
+    comment	text
+);
+QUERY: create unique index PField_name on PField using btree (name text_ops);
+QUERY: create table PSlot (
+    slotname	char(20),
+    pfname	text,
+    slotlink	char(20),
+    backlink	char(20)
+);
+QUERY: create unique index PSlot_name on PSlot using btree (slotname bpchar_ops);
+QUERY: create table PLine (
+    slotname	char(20),
+    phonenumber	char(20),
+    comment	text,
+    backlink	char(20)
+);
+QUERY: create unique index PLine_name on PLine using btree (slotname bpchar_ops);
+QUERY: create table Hub (
+    name	char(14),
+    comment	text,
+    nslots	integer
+);
+QUERY: create unique index Hub_name on Hub using btree (name bpchar_ops);
+QUERY: create table HSlot (
+    slotname	char(20),
+    hubname	char(14),
+    slotno	integer,
+    slotlink	char(20)
+);
+QUERY: create unique index HSlot_name on HSlot using btree (slotname bpchar_ops);
+QUERY: create index HSlot_hubname on HSlot using btree (hubname bpchar_ops);
+QUERY: create table System (
+    name	text,
+    comment	text
+);
+QUERY: create unique index System_name on System using btree (name text_ops);
+QUERY: create table IFace (
+    slotname	char(20),
+    sysname	text,
+    ifname	text,
+    slotlink	char(20)
+);
+QUERY: create unique index IFace_name on IFace using btree (slotname bpchar_ops);
+QUERY: create table PHone (
+    slotname	char(20),
+    comment	text,
+    slotlink	char(20)
+);
+QUERY: create unique index PHone_name on PHone using btree (slotname bpchar_ops);

contrib/plpgsql/test/mklang.sql

+--
+-- PL/pgSQL language declaration
+--
+-- $Header: /cvsroot/pgsql/contrib/plpgsql/test/Attic/mklang.sql,v 1.1 1998/08/22 12:38:36 momjian Exp $
+--
+
+create function plpgsql_call_handler() returns opaque
+	as '/usr/local/pgsql/lib/plpgsql.so'
+	language 'C';
+
+create trusted procedural language 'plpgsql'
+	handler plpgsql_call_handler
+	lancompiler 'PL/pgSQL';
+

contrib/plpgsql/test/runtest

+#!/bin/sh
+
+DB=plpgsql_test
+export DB
+
+FRONTEND="psql -n -e -q"
+export FRONTEND
+
+echo "*** destroy old $DB database ***"
+destroydb $DB
+
+echo "*** create new $DB database ***"
+createdb $DB
+
+echo "*** install PL/pgSQL ***"
+$FRONTEND -f mklang.sql -d $DB >/dev/null 2>&1
+
+echo "*** create tables ***"
+$FRONTEND -f tables.sql -d $DB >output/tables.out 2>&1
+if cmp -s output/tables.out expected/tables.out ; then
+    echo "OK"
+else
+    echo "FAILED"
+fi
+
+echo "*** create triggers ***"
+$FRONTEND -f triggers.sql -d $DB >output/triggers.out 2>&1
+if cmp -s output/triggers.out expected/triggers.out ; then
+    echo "OK"
+else
+    echo "FAILED"
+fi
+
+echo "*** create views and support functions ***"
+$FRONTEND -f views.sql -d $DB >output/views.out 2>&1
+if cmp -s output/views.out expected/views.out ; then
+    echo "OK"
+else
+    echo "FAILED"
+fi
+
+echo "*** running tests ***"
+$FRONTEND -f test.sql -d $DB >output/test.out 2>&1
+if cmp -s output/test.out expected/test.out ; then
+    echo "OK"
+else
+    echo "FAILED"
+fi
+