User and database-specific session defaults for run-time configuration

variables.  New commands ALTER DATABASE ... SET and ALTER USER ... SET.

src/backend/utils/init/miscinit.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/init/miscinit.c,v 1.82 2002/01/09 19:13:41 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/init/miscinit.c,v 1.83 2002/03/01 22:45:15 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -31,6 +31,7 @@
 #include "libpq/libpq-be.h"
 #include "miscadmin.h"
 #include "utils/builtins.h"
+#include "utils/guc.h"
 #include "utils/lsyscache.h"
 #include "utils/syscache.h"
 
@@ -437,6 +438,8 @@ void
 InitializeSessionUserId(const char *username)
 {
 	HeapTuple	userTup;
+	Datum		datum;
+	bool		isnull;
 
 	/*
 	 * Don't do scans if we're bootstrapping, none of the system catalogs
@@ -457,6 +460,21 @@ InitializeSessionUserId(const char *username)
 
 	AuthenticatedUserIsSuperuser = ((Form_pg_shadow) GETSTRUCT(userTup))->usesuper;
 
+	/*
+	 * Set up user-specific configuration variables.  This is a good
+	 * place to do it so we don't have to read pg_shadow twice during
+	 * session startup.
+	 */
+	datum = SysCacheGetAttr(SHADOWNAME, userTup,
+							Anum_pg_shadow_useconfig, &isnull);
+	if (!isnull)
+	{
+		ArrayType *a;
+
+		a = (ArrayType *) pg_detoast_datum((struct varlena *)datum);
+		ProcessGUCArray(a, PGC_S_USER);
+	}
+
 	ReleaseSysCache(userTup);
 }
 

src/backend/utils/init/postinit.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.98 2002/02/19 20:11:18 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.99 2002/03/01 22:45:15 petere Exp $
  *
  *
  *-------------------------------------------------------------------------
@@ -35,6 +35,7 @@
 #include "storage/sinval.h"
 #include "storage/smgr.h"
 #include "utils/fmgroids.h"
+#include "utils/guc.h"
 #include "utils/portal.h"
 #include "utils/relcache.h"
 #include "utils/syscache.h"
@@ -70,6 +71,10 @@ static bool ThereIsAtLeastOneUser(void);
  *
  * This is also a handy place to fetch the database encoding info out
  * of pg_database, if we are in MULTIBYTE mode.
+ *
+ * To avoid having to read pg_database more times than necessary
+ * during session startup, this place is also fitting to set up any
+ * database-specific configuration variables.
  * --------------------------------
  */
 static void
@@ -132,6 +137,25 @@ ReverifyMyDatabase(const char *name)
 			 dbform->encoding);
 #endif
 
+	/*
+	 * Set up datbase-specific configuration variables.
+	 */
+	if (IsUnderPostmaster)
+	{
+		Datum		datum;
+		bool		isnull;
+
+		datum = heap_getattr(tup, Anum_pg_database_datconfig,
+							 RelationGetDescr(pgdbrel), &isnull);
+		if (!isnull)
+		{
+			ArrayType *a;
+
+			a = (ArrayType *) pg_detoast_datum((struct varlena *)datum);
+			ProcessGUCArray(a, PGC_S_DATABASE);
+		}
+	}
+
 	heap_endscan(pgdbscan);
 	heap_close(pgdbrel, AccessShareLock);
 }

src/backend/utils/misc/guc.c

@@ -4,7 +4,7 @@
  * Support for grand unified configuration scheme, including SET
  * command, configuration file, and command line options.
  *
- * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.59 2002/02/23 01:31:36 petere Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.60 2002/03/01 22:45:16 petere Exp $
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  * Written by Peter Eisentraut <peter_e@gmx.net>.
@@ -36,6 +36,8 @@
 #include "storage/lock.h"
 #include "storage/proc.h"
 #include "tcop/tcopprot.h"
+#include "utils/array.h"
+#include "utils/builtins.h"
 #include "utils/datetime.h"
 #include "pgstat.h"
 
@@ -89,6 +91,7 @@ bool		Password_encryption = false;
 #define PG_KRB_SRVTAB ""
 #endif
 
+static bool guc_session_init = false; /* XXX mildly bogus */
 
 /*
  * Declarations for GUC tables
@@ -882,7 +885,12 @@ set_config_option(const char *name, const char *value,
 	int			elevel;
 	bool		makeDefault;
 
-	elevel = (context == PGC_SIGHUP) ? DEBUG : ERROR;
+	if (context == PGC_SIGHUP)
+		elevel = DEBUG;
+	else if (guc_session_init)
+		elevel = NOTICE;
+	else
+		elevel = ERROR;
 
 	type = find_option(name, &record);
 	if (type == PGC_NONE)
@@ -1362,3 +1370,147 @@ assign_defaultxactisolevel(const char *value)
 	else
 		elog(ERROR, "bogus transaction isolation level");
 }
+
+
+
+void
+ProcessGUCArray(ArrayType *array, GucSource source)
+{
+	int		i;
+
+	Assert(array);
+
+	for (i = 1; i <= ARR_DIMS(array)[0]; i++)
+	{
+		Datum		d;
+		bool		isnull;
+		char	   *s;
+		char	   *name;
+		char	   *value;
+
+		d = array_ref(array, 1, &i,
+					  false /*notbyvalue*/,
+					  -1 /*varlenelem*/,
+					  -1 /*varlenarray*/,
+					  &isnull);
+
+		if (isnull)
+			continue;
+
+		s = DatumGetCString(DirectFunctionCall1(textout, d));
+		ParseLongOption(s, &name, &value);
+		if (!value)
+		{
+		    elog(NOTICE, "cannot to parse setting \"%s\"", name);
+		    continue;
+		}
+
+		/* prevent errors from incorrect options */
+		guc_session_init = true;
+		
+		SetConfigOption(name, value, PGC_SUSET, source);
+
+		guc_session_init = false;
+	}
+}
+
+
+
+ArrayType *
+GUCArrayAdd(ArrayType *array, const char *name, const char *value)
+{
+	Datum		datum;
+	char	   *newval;
+	ArrayType  *a;
+
+	Assert(name);
+	Assert(value);
+
+	/* test if the option is valid */
+	set_config_option(name, value,
+					  superuser() ? PGC_SUSET : PGC_USERSET,
+					  false, PGC_S_INFINITY);
+
+	newval = palloc(strlen(name) + 1 + strlen(value) + 1);
+	sprintf(newval, "%s=%s", name, value);
+	datum = DirectFunctionCall1(textin, CStringGetDatum(newval));
+	
+	if (array)
+	{
+		int		index;
+		bool	isnull;
+		int		i;
+
+		index = ARR_DIMS(array)[0] + 1;	/* add after end */
+
+		for (i = 1; i <= ARR_DIMS(array)[0]; i++)
+		{
+			Datum		d;
+			char	   *current;
+
+			d = array_ref(array, 1, &i,
+						  false /*notbyvalue*/,
+						  -1 /*varlenelem*/,
+						  -1 /*varlenarray*/,
+						  &isnull);
+			current = DatumGetCString(DirectFunctionCall1(textout, d));
+			if (strncmp(current, newval, strlen(name) + 1)==0)
+			{
+				index = i;
+				break;
+			}
+		}
+
+		isnull = false;
+		a = array_set(array, 1, &index, datum, false/*notbyval*/, -1, -1, &isnull);
+	}
+	else
+		a = construct_array(&datum, 1, false, -1, 'i');
+
+	return a;
+}
+
+
+
+ArrayType *
+GUCArrayDelete(ArrayType *array, const char *name)
+{
+	ArrayType *newarray;
+	int i;
+	int index;
+
+	Assert(name);
+	Assert(array);
+
+	/* test if the option is valid */
+	set_config_option(name, NULL,
+					  superuser() ? PGC_SUSET : PGC_USERSET,
+					  false, PGC_S_INFINITY);
+
+	newarray = construct_array(NULL, 0, false, -1, 'i');
+	index = 1;
+
+	for (i = 1; i <= ARR_DIMS(array)[0]; i++)
+	{
+		Datum		d;
+		char	   *val;
+		bool		isnull;
+
+		d = array_ref(array, 1, &i,
+					  false /*notbyvalue*/,
+					  -1 /*varlenelem*/,
+					  -1 /*varlenarray*/,
+					  &isnull);
+		val = DatumGetCString(DirectFunctionCall1(textout, d));
+
+		if (strncmp(val, name, strlen(name))==0
+			&& val[strlen(name)] == '=')
+			continue;
+
+		isnull = false;
+		newarray = array_set(newarray, 1, &index, d, false/*notbyval*/, -1, -1, &isnull);
+		index++;
+	}
+
+	return newarray;
+}