Create a new GUC variable search_path to control the namespace search

path.  The default behavior if no per-user schemas are created is that
all users share a 'public' namespace, thus providing behavior backwards
compatible with 7.2 and earlier releases.  Probably the semantics and
default setting will need to be fine-tuned, but this is a start.

src/backend/utils/adt/varlena.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.80 2002/03/30 01:02:42 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.81 2002/04/01 03:34:26 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1046,28 +1046,82 @@ name_text(PG_FUNCTION_ARGS)
  * functions that take a text parameter representing a qualified name.
  * We split the name at dots, downcase if not double-quoted, and
  * truncate names if they're too long.
- *
- * This is a kluge, really, and exists only for historical reasons.
- * A better notation for such functions would be nextval(relname).
  */
 List *
 textToQualifiedNameList(text *textval, const char *caller)
 {
 	char	   *rawname;
-	char	   *nextp;
 	List	   *result = NIL;
+	List	   *namelist;
+	List	   *l;
 
 	/* Convert to C string (handles possible detoasting). */
 	/* Note we rely on being able to modify rawname below. */
 	rawname = DatumGetCString(DirectFunctionCall1(textout,
 												  PointerGetDatum(textval)));
-	nextp = rawname;
 
+	if (!SplitIdentifierString(rawname, '.', &namelist))
+		elog(ERROR, "%s: invalid name syntax", caller);
+
+	if (namelist == NIL)
+		elog(ERROR, "%s: invalid name syntax", caller);
+
+	foreach(l, namelist)
+	{
+		char   *curname = (char *) lfirst(l);
+
+		result = lappend(result, makeString(pstrdup(curname)));
+	}
+
+	pfree(rawname);
+	freeList(namelist);
+
+	return result;
+}
+
+/*
+ * SplitIdentifierString --- parse a string containing identifiers
+ *
+ * This is the guts of textToQualifiedNameList, and is exported for use in
+ * other situations such as parsing GUC variables.  In the GUC case, it's
+ * important to avoid memory leaks, so the API is designed to minimize the
+ * amount of stuff that needs to be allocated and freed.
+ *
+ * Inputs:
+ *	rawstring: the input string; must be overwritable!  On return, it's
+ *			   been modified to contain the separated identifiers.
+ *	separator: the separator punctuation expected between identifiers
+ *			   (typically '.' or ',').  Whitespace may also appear around
+ *			   identifiers.
+ * Outputs:
+ *	namelist: filled with a palloc'd list of pointers to identifiers within
+ *			  rawstring.  Caller should freeList() this even on error return.
+ *
+ * Returns TRUE if okay, FALSE if there is a syntax error in the string.
+ *
+ * Note that an empty string is considered okay here, though not in
+ * textToQualifiedNameList.
+ */
+bool
+SplitIdentifierString(char *rawstring, char separator,
+					  List **namelist)
+{
+	char	   *nextp = rawstring;
+	bool		done = false;
+
+	*namelist = NIL;
+
+	while (isspace((unsigned char) *nextp))
+		nextp++;				/* skip leading whitespace */
+
+	if (*nextp == '\0')
+		return true;			/* allow empty string */
+
+	/* At the top of the loop, we are at start of a new identifier. */
 	do
 	{
 		char	   *curname;
 		char	   *endp;
-		char	   *cp;
 		int			curlen;
 
 		if (*nextp == '\"')
@@ -1078,56 +1132,54 @@ textToQualifiedNameList(text *textval, const char *caller)
 			{
 				endp = strchr(nextp + 1, '\"');
 				if (endp == NULL)
-					elog(ERROR, "%s: invalid quoted name: mismatched quotes",
-						 caller);
+					return false; /* mismatched quotes */
 				if (endp[1] != '\"')
 					break;		/* found end of quoted name */
 				/* Collapse adjacent quotes into one quote, and look again */
 				memmove(endp, endp+1, strlen(endp));
 				nextp = endp;
 			}
-			*endp = '\0';
+			/* endp now points at the terminating quote */
 			nextp = endp + 1;
-			if (*nextp)
-			{
-				if (*nextp != '.')
-					elog(ERROR, "%s: invalid name syntax",
-						 caller);
-				nextp++;
-				if (*nextp == '\0')
-					elog(ERROR, "%s: invalid name syntax",
-						 caller);
-			}
 		}
 		else
 		{
-			/* Unquoted name --- extends to next dot */
-			if (*nextp == '\0')				/* empty name not okay here */
-				elog(ERROR, "%s: invalid name syntax",
-					 caller);
+			/* Unquoted name --- extends to separator or whitespace */
 			curname = nextp;
-			endp = strchr(nextp, '.');
-			if (endp)
+			while (*nextp && *nextp != separator &&
+				   !isspace((unsigned char) *nextp))
 			{
-				*endp = '\0';
-				nextp = endp + 1;
-				if (*nextp == '\0')
-					elog(ERROR, "%s: invalid name syntax",
-						 caller);
-			}
-			else
-				nextp = nextp + strlen(nextp);
-			/*
-			 * It's important that this match the identifier downcasing code
-			 * used by backend/parser/scan.l.
-			 */
-			for (cp = curname; *cp; cp++)
-			{
-				if (isupper((unsigned char) *cp))
-					*cp = tolower((unsigned char) *cp);
+				/*
+				 * It's important that this match the identifier downcasing
+				 * code used by backend/parser/scan.l.
+				 */
+				if (isupper((unsigned char) *nextp))
+					*nextp = tolower((unsigned char) *nextp);
+				nextp++;
 			}
+			endp = nextp;
+			if (curname == nextp)
+				return false;	/* empty unquoted name not allowed */
 		}
 
+		while (isspace((unsigned char) *nextp))
+			nextp++;			/* skip trailing whitespace */
+
+		if (*nextp == separator)
+		{
+			nextp++;
+			while (isspace((unsigned char) *nextp))
+				nextp++;		/* skip leading whitespace for next */
+			/* we expect another name, so done remains false */
+		}
+		else if (*nextp == '\0')
+			done = true;
+		else
+			return false;		/* invalid syntax */
+
+		/* Now safe to overwrite separator with a null */
+		*endp = '\0';
+
 		/* Truncate name if it's overlength; again, should match scan.l */
 		curlen = strlen(curname);
 		if (curlen >= NAMEDATALEN)
@@ -1143,15 +1195,12 @@ textToQualifiedNameList(text *textval, const char *caller)
 		/*
 		 * Finished isolating current name --- add it to list
 		 */
-		result = lappend(result, makeString(pstrdup(curname)));
-		/*
-		 * Loop back if we found a dot
-		 */
-	} while (*nextp);
+		*namelist = lappend(*namelist, curname);
 
-	pfree(rawname);
+		/* Loop back if we didn't reach end of string */
+	} while (!done);
 
-	return result;
+	return true;
 }
 
 

src/backend/utils/init/postinit.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.101 2002/03/31 06:26:32 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/init/postinit.c,v 1.102 2002/04/01 03:34:26 tgl Exp $
  *
  *
  *-------------------------------------------------------------------------
@@ -24,10 +24,11 @@
 #include "catalog/catalog.h"
 #include "access/heapam.h"
 #include "catalog/catname.h"
+#include "catalog/namespace.h"
 #include "catalog/pg_database.h"
 #include "catalog/pg_shadow.h"
 #include "commands/trigger.h"
-#include "commands/variable.h"	/* for set_default_client_encoding() */
+#include "commands/variable.h"
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
 #include "storage/backendid.h"
@@ -372,11 +373,6 @@ InitPostgres(const char *dbname, const char *username)
 	if (!bootstrap)
 		ReverifyMyDatabase(dbname);
 
-#ifdef MULTIBYTE
-	/* set default client encoding --- uses info from ReverifyMyDatabase */
-	set_default_client_encoding();
-#endif
-
 	/*
 	 * Final phase of relation cache startup: write a new cache file
 	 * if necessary.  This is done after ReverifyMyDatabase to avoid
@@ -384,6 +380,19 @@ InitPostgres(const char *dbname, const char *username)
 	 */
 	RelationCacheInitializePhase3();
 
+	/*
+	 * Initialize various default states that can't be set up until
+	 * we've selected the active user and done ReverifyMyDatabase.
+	 */
+
+	/* set default namespace search path */
+	InitializeSearchPath();
+
+#ifdef MULTIBYTE
+	/* set default client encoding --- uses info from ReverifyMyDatabase */
+	set_default_client_encoding();
+#endif
+
 	/*
 	 * Set up process-exit callback to do pre-shutdown cleanup.  This should
 	 * be last because we want shmem_exit to call this routine before the exit

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 1.63 2002/03/24 04:31:08 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.64 2002/04/01 03:34:26 tgl Exp $
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  * Written by Peter Eisentraut <peter_e@gmx.net>.
@@ -21,6 +21,7 @@
 #include "utils/guc.h"
 
 #include "access/xlog.h"
+#include "catalog/namespace.h"
 #include "commands/async.h"
 #include "fmgr.h"
 #include "libpq/auth.h"
@@ -574,6 +575,11 @@ static struct config_string
 		"$libdir", NULL, NULL
 	},
 
+	{
+		"search_path", PGC_USERSET, PGC_S_DEFAULT, &namespace_search_path,
+		"$user,public", check_search_path, assign_search_path
+	},
+
 	{
 		"krb_server_keyfile", PGC_POSTMASTER, PGC_S_DEFAULT, &pg_krb_server_keyfile,
 		PG_KRB_SRVTAB, NULL, NULL
@@ -899,7 +905,7 @@ set_config_option(const char *name, const char *value,
 	int			elevel;
 	bool		makeDefault;
 
-	if (context == PGC_SIGHUP)
+	if (context == PGC_SIGHUP || source == PGC_S_DEFAULT)
 		elevel = DEBUG1;
 	else if (guc_session_init)
 		elevel = INFO;
@@ -1414,7 +1420,7 @@ ProcessGUCArray(ArrayType *array, GucSource source)
 		ParseLongOption(s, &name, &value);
 		if (!value)
 		{
-			elog(WARNING, "cannot to parse setting \"%s\"", name);
+			elog(WARNING, "cannot parse setting \"%s\"", name);
 			continue;
 		}
 

src/backend/utils/misc/postgresql.conf.sample

@@ -191,6 +191,7 @@
 #	Misc
 #
 #dynamic_library_path = '$libdir'
+#search_path = '$user,public'
 #australian_timezones = false
 #authentication_timeout = 60	# min 1, max 600
 #deadlock_timeout = 1000