Index: contrib/showguc/Makefile
===================================================================
RCS file: contrib/showguc/Makefile
diff -N contrib/showguc/Makefile
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- contrib/showguc/Makefile	27 May 2002 00:24:44 -0000
***************
*** 0 ****
--- 1,9 ----
+ subdir = contrib/showguc
+ top_builddir = ../..
+ include $(top_builddir)/src/Makefile.global
+ 
+ MODULES = showguc
+ DATA_built = showguc.sql
+ DOCS = README.showguc
+ 
+ include $(top_srcdir)/contrib/contrib-global.mk
Index: contrib/showguc/README.showguc
===================================================================
RCS file: contrib/showguc/README.showguc
diff -N contrib/showguc/README.showguc
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- contrib/showguc/README.showguc	10 Jun 2002 00:16:48 -0000
***************
*** 0 ****
--- 1,105 ----
+ /*
+  * showguc
+  *
+  * Sample to demonstrate a C function which returns setof composite.
+  * Joe Conway <mail@joeconway.com>
+  *
+  * Copyright 2002 by PostgreSQL Global Development Group
+  *
+  * Permission to use, copy, modify, and distribute this software and its
+  * documentation for any purpose, without fee, and without a written agreement
+  * is hereby granted, provided that the above copyright notice and this
+  * paragraph and the following two paragraphs appear in all copies.
+  * 
+  * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
+  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
+  * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
+  * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS 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
+  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+  * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
+  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+  *
+  */
+ Version 0.1 (9 June, 2002):
+   First release
+ 
+ Release Notes:
+ 
+   Version 0.1
+     - initial release    
+ 
+ Installation:
+   Place these files in a directory called 'showguc' under 'contrib' in the PostgreSQL source tree. Then run:
+ 
+     make
+     make install
+ 
+   You can use showguc.sql to create the functions in your database of choice, e.g.
+ 
+     psql -U postgres template1 < showguc.sql
+ 
+   installs following functions into database template1:
+ 
+      show_all_vars() - returns all GUC variables
+      show_var(text) - returns value of the requested GUC variable
+ 
+ Documentation
+ ==================================================================
+ Name
+ 
+ show_all_vars() - returns all GUC variables
+ 
+ Synopsis
+ 
+ show_all_vars()
+ 
+ Inputs
+ 
+   none
+ 
+ Outputs
+ 
+   Returns setof __gucvar, where __gucvar is (varname TEXT, varval TEXT). All
+     GUC variables displayed by SHOW ALL are returned as a set.
+ 
+ Example usage
+ 
+ test=# select * from show_all_vars() where varname = 'wal_sync_method';
+      varname     |  varval
+ -----------------+-----------
+  wal_sync_method | fdatasync
+ (1 row)
+ 
+ ==================================================================
+ Name
+ 
+ show_var(text varname) - returns value of GUC variable varname
+ 
+ Synopsis
+ 
+ show_var(varname)
+ 
+ Inputs
+ 
+   varname
+     The name of a GUC variable
+ 
+ Outputs
+ 
+   Returns the current value of varname.
+ 
+ Example usage
+ 
+ test=# select show_var('wal_sync_method');
+  show_var
+ -----------
+  fdatasync
+ (1 row)
+ 
+ ==================================================================
+ -- Joe Conway
+ 
Index: contrib/showguc/showguc.c
===================================================================
RCS file: contrib/showguc/showguc.c
diff -N contrib/showguc/showguc.c
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- contrib/showguc/showguc.c	10 Jun 2002 00:02:14 -0000
***************
*** 0 ****
--- 1,152 ----
+ /*
+  * showguc
+  *
+  * Sample to demonstrate a C function which returns setof composite.
+  * Joe Conway <mail@joeconway.com>
+  *
+  * Copyright 2002 by PostgreSQL Global Development Group
+  *
+  * Permission to use, copy, modify, and distribute this software and its
+  * documentation for any purpose, without fee, and without a written agreement
+  * is hereby granted, provided that the above copyright notice and this
+  * paragraph and the following two paragraphs appear in all copies.
+  * 
+  * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
+  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
+  * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
+  * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS 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
+  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+  * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
+  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+  *
+  */
+ #include "postgres.h"
+ 
+ #include "fmgr.h"
+ #include "funcapi.h"
+ #include "utils/builtins.h"
+ #include "utils/guc.h"
+ 
+ #include "showguc.h"
+ 
+ /*
+  * showguc_all - equiv to SHOW ALL command but implemented as
+  * an SRF.
+  */
+ PG_FUNCTION_INFO_V1(showguc_all);
+ Datum
+ showguc_all(PG_FUNCTION_ARGS)
+ {
+ 	FuncCallContext	   *funcctx;
+ 	TupleDesc			tupdesc;
+ 	int					call_cntr;
+ 	int					max_calls;
+ 	TupleTableSlot	   *slot;
+ 	AttInMetadata	   *attinmeta;
+ 
+ 	/* stuff done only on the first call of the function */
+  	if(SRF_IS_FIRSTPASS())
+  	{
+ 		/* create a function context for cross-call persistence */
+  		funcctx = SRF_FIRSTCALL_INIT();
+ 
+ 		/*
+ 		 * Build a tuple description for a pg__guc tuple
+ 		 */
+ 		tupdesc = RelationNameGetTupleDesc("__gucvar");
+ 
+ 		/* allocate a slot for a tuple with this tupdesc */
+ 		slot = TupleDescGetSlot(tupdesc);
+ 
+ 		/* assign slot to function context */
+ 		funcctx->slot = slot;
+ 
+ 		/*
+ 		 * Generate attribute metadata needed later to produce tuples from raw
+ 		 * C strings
+ 		 */
+ 		attinmeta = TupleDescGetAttInMetadata(tupdesc);
+ 		funcctx->attinmeta = attinmeta;
+ 
+ 		/* total number of tuples to be returned */
+ 		funcctx->max_calls = GetNumGUCConfigOptions();
+     }
+ 
+ 	/* stuff done on every call of the function */
+  	funcctx = SRF_PERCALL_SETUP(funcctx);
+ 
+ 	call_cntr = funcctx->call_cntr;
+ 	max_calls = funcctx->max_calls;
+ 	slot = funcctx->slot;
+ 	attinmeta = funcctx->attinmeta;
+  
+  	if (call_cntr < max_calls)	/* do when there is more left to send */
+  	{
+ 		char	   *varname;
+ 		char	   *varval;
+ 		char	   **values;
+ 		HeapTuple	tuple;
+ 		Datum		result;
+ 
+ 		/*
+ 		 * Get the next GUC variable name and value
+ 		 */
+ 		varval = GetGUCConfigOptionNum(call_cntr, &varname);
+ 
+ 		/*
+ 		 * Prepare a values array for storage in our slot.
+ 		 * This should be an array of C strings which will
+ 		 * be processed later by the appropriate "in" functions.
+ 		 */
+ 		values = (char **) palloc(2 * sizeof(char *));
+ 		values[0] = varname;
+ 		values[1] = varval;
+ 
+ 		/* build a tuple */
+ 		tuple = BuildTupleFromCStrings(attinmeta, values);
+ 
+ 		/* make the tuple into a datum */
+ 		result = TupleGetDatum(slot, tuple);
+ 
+ 		/* Clean up */
+ 		pfree(varname);
+ 		pfree(values);
+ 
+  		SRF_RETURN_NEXT(funcctx, result);
+  	}
+  	else	/* do when there is no more left */
+  	{
+  		SRF_RETURN_DONE(funcctx);
+  	}
+ }
+ 
+ 
+ /*
+  * showguc_name - equiv to SHOW X command but implemented as
+  * a function.
+  */
+ PG_FUNCTION_INFO_V1(showguc_name);
+ Datum
+ showguc_name(PG_FUNCTION_ARGS)
+ {
+ 	char   *varname;
+ 	char   *varval;
+ 	text   *result_text;
+ 
+ 	/* Get the GUC variable name */
+ 	varname = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(0))));
+ 
+ 	/* Get the value */
+ 	varval = GetGUCConfigOptionName(varname);
+ 
+ 	/* Convert to text */
+ 	result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(varval)));
+ 
+ 	/* return it */
+ 	PG_RETURN_TEXT_P(result_text);
+ }
+ 
Index: contrib/showguc/showguc.h
===================================================================
RCS file: contrib/showguc/showguc.h
diff -N contrib/showguc/showguc.h
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- contrib/showguc/showguc.h	10 Jun 2002 00:01:02 -0000
***************
*** 0 ****
--- 1,37 ----
+ /*
+  * showguc
+  *
+  * Sample to demonstrate a C function which returns setof composite.
+  * Joe Conway <mail@joeconway.com>
+  *
+  * Copyright 2002 by PostgreSQL Global Development Group
+  *
+  * Permission to use, copy, modify, and distribute this software and its
+  * documentation for any purpose, without fee, and without a written agreement
+  * is hereby granted, provided that the above copyright notice and this
+  * paragraph and the following two paragraphs appear in all copies.
+  * 
+  * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
+  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
+  * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
+  * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS 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
+  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+  * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
+  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+  *
+  */
+ 
+ #ifndef SHOWGUC_H
+ #define SHOWGUC_H
+ 
+ /*
+  * External declarations
+  */
+ extern Datum showguc_all(PG_FUNCTION_ARGS);
+ extern Datum showguc_name(PG_FUNCTION_ARGS);
+ 
+ #endif   /* SHOWGUC_H */
Index: contrib/showguc/showguc.sql.in
===================================================================
RCS file: contrib/showguc/showguc.sql.in
diff -N contrib/showguc/showguc.sql.in
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- contrib/showguc/showguc.sql.in	10 Jun 2002 00:03:13 -0000
***************
*** 0 ****
--- 1,10 ----
+ CREATE VIEW __gucvar AS
+   SELECT
+     ''::TEXT AS varname,
+     ''::TEXT AS varval;
+ 
+ CREATE OR REPLACE FUNCTION show_all_vars() RETURNS setof __gucvar
+   AS 'MODULE_PATHNAME','showguc_all' LANGUAGE 'c' STABLE STRICT;
+ 
+ CREATE OR REPLACE FUNCTION show_var(text) RETURNS text
+   AS 'MODULE_PATHNAME','showguc_name' LANGUAGE 'c' STABLE STRICT;
Index: src/backend/utils/misc/guc.c
===================================================================
RCS file: /opt/src/cvs/pgsql/src/backend/utils/misc/guc.c,v
retrieving revision 1.69
diff -c -r1.69 guc.c
*** src/backend/utils/misc/guc.c	17 May 2002 20:32:29 -0000	1.69
--- src/backend/utils/misc/guc.c	9 Jun 2002 22:51:45 -0000
***************
*** 824,830 ****
  
  
  static int guc_var_compare(const void *a, const void *b);
! static void _ShowOption(struct config_generic *record);
  
  
  /*
--- 824,830 ----
  
  
  static int guc_var_compare(const void *a, const void *b);
! static char *_ShowOption(struct config_generic *record);
  
  
  /*
***************
*** 2204,2215 ****
  ShowGUCConfigOption(const char *name)
  {
  	struct config_generic *record;
  
  	record = find_option(name);
  	if (record == NULL)
  		elog(ERROR, "Option '%s' is not recognized", name);
  
! 	_ShowOption(record);
  }
  
  /*
--- 2204,2221 ----
  ShowGUCConfigOption(const char *name)
  {
  	struct config_generic *record;
+ 	char *val;
  
  	record = find_option(name);
  	if (record == NULL)
  		elog(ERROR, "Option '%s' is not recognized", name);
  
! 	val = _ShowOption(record);
! 	if(val != NULL)
! 	{
! 		elog(INFO, "%s is %s", record->name, val);
! 		pfree(val);
! 	}
  }
  
  /*
***************
*** 2219,2239 ****
  ShowAllGUCConfig(void)
  {
  	int			i;
  
  	for (i = 0; i < num_guc_variables; i++)
  	{
  		struct config_generic *conf = guc_variables[i];
  
  		if ((conf->flags & GUC_NO_SHOW_ALL) == 0)
! 			_ShowOption(conf);
  	}
  }
  
! static void
  _ShowOption(struct config_generic *record)
  {
  	char		buffer[256];
  	const char *val;
  
  	switch (record->vartype)
  	{
--- 2225,2295 ----
  ShowAllGUCConfig(void)
  {
  	int			i;
+ 	char	   *val;
  
  	for (i = 0; i < num_guc_variables; i++)
  	{
  		struct config_generic *conf = guc_variables[i];
  
  		if ((conf->flags & GUC_NO_SHOW_ALL) == 0)
! 		{
! 			val = _ShowOption(conf);
! 			if(val != NULL)
! 			{
! 				elog(INFO, "%s is %s", conf->name, val);
! 				pfree(val);
! 			}
! 		}
  	}
  }
  
! /*
!  * Return GUC variable value by name
!  */
! char *
! GetGUCConfigOptionName(const char *name)
! {
! 	struct config_generic *record;
! 
! 	record = find_option(name);
! 	if (record == NULL)
! 		elog(ERROR, "Option '%s' is not recognized", name);
! 
! 	return _ShowOption(record);
! }
! 
! /*
!  * Return GUC variable value and set varname for a specific
!  * variable by number.
!  */
! char *
! GetGUCConfigOptionNum(int varnum, char **varname)
! {
! 	struct config_generic *conf = guc_variables[varnum];
! 
! 	*varname = pstrdup(conf->name);
! 
! 	if ((conf->flags & GUC_NO_SHOW_ALL) == 0)
! 		return _ShowOption(conf);
! 	else
! 		return NULL;
! }
! 
! /*
!  * Return the total number of GUC variables
!  */
! int
! GetNumGUCConfigOptions(void)
! {
! 	return num_guc_variables;
! }
! 
! static char *
  _ShowOption(struct config_generic *record)
  {
  	char		buffer[256];
  	const char *val;
+ 	char	   *retval;
  
  	switch (record->vartype)
  	{
***************
*** 2297,2303 ****
  			break;
  	}
  
! 	elog(INFO, "%s is %s", record->name, val);
  }
  
  
--- 2353,2361 ----
  			break;
  	}
  
! 	retval = pstrdup(val);
! 
! 	return retval;
  }
  
  
Index: src/include/utils/guc.h
===================================================================
RCS file: /opt/src/cvs/pgsql/src/include/utils/guc.h,v
retrieving revision 1.17
diff -c -r1.17 guc.h
*** src/include/utils/guc.h	17 May 2002 01:19:19 -0000	1.17
--- src/include/utils/guc.h	9 Jun 2002 22:45:20 -0000
***************
*** 86,91 ****
--- 86,94 ----
  							  bool isLocal, bool DoIt);
  extern void ShowGUCConfigOption(const char *name);
  extern void ShowAllGUCConfig(void);
+ extern char *GetGUCConfigOptionName(const char *name);
+ extern char *GetGUCConfigOptionNum(int varnum, char **varname);
+ extern int GetNumGUCConfigOptions(void);
  
  extern void SetPGVariable(const char *name, List *args, bool is_local);
  extern void GetPGVariable(const char *name);