Create the pg_pltemplate system catalog to hold template information

for procedural languages.  This replaces the hard-wired table I had
originally proposed as a stopgap solution.  For the moment, the initial
contents only include languages shipped with the core distribution.

8 files changed, 187 insertions, 69 deletions

diff --git a/src/backend/catalog/Makefile b/src/backend/catalog/Makefile
index c2dd227d1d9..67a46e93c0c 100644
--- a/src/backend/catalog/Makefile
+++ b/src/backend/catalog/Makefile
@@ -2,7 +2,7 @@
 #
 # Makefile for backend/catalog
 #
-# $PostgreSQL: pgsql/src/backend/catalog/Makefile,v 1.56 2005/07/14 05:13:39 tgl Exp $
+# $PostgreSQL: pgsql/src/backend/catalog/Makefile,v 1.57 2005/09/08 20:07:41 tgl Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -32,8 +32,9 @@ POSTGRES_BKI_SRCS := $(addprefix $(top_srcdir)/src/include/catalog/,\
 	pg_operator.h pg_opclass.h pg_am.h pg_amop.h pg_amproc.h \
 	pg_language.h pg_largeobject.h pg_aggregate.h pg_statistic.h \
 	pg_rewrite.h pg_trigger.h pg_listener.h pg_description.h pg_cast.h \
-	pg_namespace.h pg_conversion.h pg_database.h pg_shdepend.h \
-	pg_authid.h pg_auth_members.h pg_tablespace.h pg_depend.h \
+	pg_namespace.h pg_conversion.h pg_depend.h \
+	pg_database.h pg_tablespace.h pg_pltemplate.h \
+	pg_authid.h pg_auth_members.h pg_shdepend.h \
 	indexing.h \
     )
 
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index d6bb902274e..c2bb4a2d9c8 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/functioncmds.c,v 1.66 2005/08/22 17:38:20 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/functioncmds.c,v 1.67 2005/09/08 20:07:41 tgl Exp $
  *
  * DESCRIPTION
  *	  These routines take the parse tree and pick out the
@@ -44,6 +44,7 @@
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"
+#include "commands/proclang.h"
 #include "miscadmin.h"
 #include "optimizer/cost.h"
 #include "parser/parse_func.h"
@@ -543,17 +544,11 @@ CreateFunction(CreateFunctionStmt *stmt)
 								   PointerGetDatum(languageName),
 								   0, 0, 0);
 	if (!HeapTupleIsValid(languageTuple))
-		/* Add any new languages to this list to invoke the hint. */
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_OBJECT),
 				 errmsg("language \"%s\" does not exist", languageName),
-				 (strcmp(languageName, "plperl") == 0 ||
-				  strcmp(languageName, "plperlu") == 0 ||
-				  strcmp(languageName, "plpgsql") == 0 ||
-				  strcmp(languageName, "plpythonu") == 0 ||
-				  strcmp(languageName, "pltcl") == 0 ||
-				  strcmp(languageName, "pltclu") == 0) ?
-				 errhint("You need to use \"createlang\" to load the language into the database.") : 0));
+				 (PLTemplateExists(languageName) ?
+				  errhint("Use CREATE LANGUAGE to load the language into the database.") : 0)));
 
 	languageOid = HeapTupleGetOid(languageTuple);
 	languageStruct = (Form_pg_language) GETSTRUCT(languageTuple);
diff --git a/src/backend/commands/proclang.c b/src/backend/commands/proclang.c
index 499523ae007..4155dc179ad 100644
--- a/src/backend/commands/proclang.c
+++ b/src/backend/commands/proclang.c
@@ -7,18 +7,20 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/proclang.c,v 1.61 2005/09/05 23:50:48 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/proclang.c,v 1.62 2005/09/08 20:07:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
 
+#include "access/genam.h"
 #include "access/heapam.h"
 #include "catalog/dependency.h"
 #include "catalog/indexing.h"
 #include "catalog/namespace.h"
 #include "catalog/pg_language.h"
 #include "catalog/pg_namespace.h"
+#include "catalog/pg_pltemplate.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "commands/proclang.h"
@@ -35,11 +37,10 @@
 
 typedef struct
 {
-	char	   *lanname;		/* PL name */
-	bool		lantrusted;		/* trusted? */
-	char	   *lanhandler;		/* name of handler function */
-	char	   *lanvalidator;	/* name of validator function, or NULL */
-	char	   *lanlibrary;		/* path of shared library */
+	bool		tmpltrusted;	/* trusted? */
+	char	   *tmplhandler;	/* name of handler function */
+	char	   *tmplvalidator;	/* name of validator function, or NULL */
+	char	   *tmpllibrary;	/* path of shared library */
 } PLTemplate;
 
 static void create_proc_lang(const char *languageName,
@@ -91,11 +92,18 @@ CreateProceduralLanguage(CreatePLangStmt *stmt)
 		List	*funcname;
 
 		/*
+		 * Give a notice if we are ignoring supplied parameters.
+		 */
+		if (stmt->plhandler)
+			ereport(NOTICE,
+					(errmsg("using pg_pltemplate information instead of CREATE LANGUAGE parameters")));
+
+		/*
 		 * Find or create the handler function, which we force to be in
 		 * the pg_catalog schema.  If already present, it must have the
 		 * correct return type.
 		 */
-		funcname = SystemFuncName(pltemplate->lanhandler);
+		funcname = SystemFuncName(pltemplate->tmplhandler);
 		handlerOid = LookupFuncName(funcname, 0, funcargtypes, true);
 		if (OidIsValid(handlerOid))
 		{
@@ -108,15 +116,15 @@ CreateProceduralLanguage(CreatePLangStmt *stmt)
 		}
 		else
 		{
-			handlerOid = ProcedureCreate(pltemplate->lanhandler,
+			handlerOid = ProcedureCreate(pltemplate->tmplhandler,
 										 PG_CATALOG_NAMESPACE,
 										 false,		/* replace */
 										 false,		/* returnsSet */
 										 LANGUAGE_HANDLEROID,
 										 ClanguageId,
 										 F_FMGR_C_VALIDATOR,
-										 pltemplate->lanhandler,
-										 pltemplate->lanlibrary,
+										 pltemplate->tmplhandler,
+										 pltemplate->tmpllibrary,
 										 false,		/* isAgg */
 										 false,		/* security_definer */
 										 false,		/* isStrict */
@@ -131,22 +139,22 @@ CreateProceduralLanguage(CreatePLangStmt *stmt)
 		 * Likewise for the validator, if required; but we don't care about
 		 * its return type.
 		 */
-		if (pltemplate->lanvalidator)
+		if (pltemplate->tmplvalidator)
 		{
-			funcname = SystemFuncName(pltemplate->lanvalidator);
+			funcname = SystemFuncName(pltemplate->tmplvalidator);
 			funcargtypes[0] = OIDOID;
 			valOid = LookupFuncName(funcname, 1, funcargtypes, true);
 			if (!OidIsValid(valOid))
 			{
-				valOid = ProcedureCreate(pltemplate->lanvalidator,
+				valOid = ProcedureCreate(pltemplate->tmplvalidator,
 										 PG_CATALOG_NAMESPACE,
 										 false,		/* replace */
 										 false,		/* returnsSet */
 										 VOIDOID,
 										 ClanguageId,
 										 F_FMGR_C_VALIDATOR,
-										 pltemplate->lanvalidator,
-										 pltemplate->lanlibrary,
+										 pltemplate->tmplvalidator,
+										 pltemplate->tmpllibrary,
 										 false,		/* isAgg */
 										 false,		/* security_definer */
 										 false,		/* isStrict */
@@ -162,7 +170,7 @@ CreateProceduralLanguage(CreatePLangStmt *stmt)
 
 		/* ok, create it */
 		create_proc_lang(languageName, handlerOid, valOid,
-						 pltemplate->lantrusted);
+						 pltemplate->tmpltrusted);
 	}
 	else
 	{
@@ -170,17 +178,13 @@ CreateProceduralLanguage(CreatePLangStmt *stmt)
 		 * No template, so use the provided information.  If there's
 		 * no handler clause, the user is trying to rely on a template
 		 * that we don't have, so complain accordingly.
-		 *
-		 * XXX In 8.2, replace the detail message with a hint to look in
-		 * pg_pltemplate.
 		 */
 		if (!stmt->plhandler)
 			ereport(ERROR,
 					(errcode(ERRCODE_UNDEFINED_OBJECT),
 					 errmsg("unsupported language \"%s\"",
 							languageName),
-					 errdetail("Supported languages are plpgsql, pltcl, pltclu, "
-							   "plperl, plperlu, and plpythonu.")));
+					 errhint("The supported languages are listed in the pg_pltemplate system catalog.")));
 
 		/*
 		 * Lookup the PL handler function and check that it is of the expected
@@ -291,41 +295,76 @@ create_proc_lang(const char *languageName,
 
 /*
  * Look to see if we have template information for the given language name.
- *
- * XXX for PG 8.1, the template info is hard-wired.  This is to be replaced
- * by a shared system catalog in 8.2.
- *
- * XXX if you add languages to this list, add them also to the errdetail
- * message above and the list in functioncmds.c.  Those hard-wired lists
- * should go away in 8.2, also.
  */
 static PLTemplate *
 find_language_template(const char *languageName)
 {
-	static PLTemplate templates[] = {
-		{ "plpgsql", true, "plpgsql_call_handler", "plpgsql_validator",
-		  "$libdir/plpgsql" },
-		{ "pltcl", true, "pltcl_call_handler", NULL,
-		  "$libdir/pltcl" },
-		{ "pltclu", false, "pltclu_call_handler", NULL,
-		  "$libdir/pltcl" },
-		{ "plperl", true, "plperl_call_handler", "plperl_validator",
-		  "$libdir/plperl" },
-		{ "plperlu", false, "plperl_call_handler", "plperl_validator",
-		  "$libdir/plperl" },
-		{ "plpythonu", false, "plpython_call_handler", NULL,
-		  "$libdir/plpython" },
-		{ NULL, false, NULL, NULL, NULL }
-	};
-
-	PLTemplate *ptr;
-
-	for (ptr = templates; ptr->lanname != NULL; ptr++)
+	PLTemplate *result;
+	Relation	rel;
+	SysScanDesc scan;
+	ScanKeyData key;
+	HeapTuple	tup;
+
+	rel = heap_open(PLTemplateRelationId, AccessShareLock);
+
+	ScanKeyInit(&key,
+				Anum_pg_pltemplate_tmplname,
+				BTEqualStrategyNumber, F_NAMEEQ,
+				NameGetDatum(languageName));
+	scan = systable_beginscan(rel, PLTemplateNameIndexId, true,
+							  SnapshotNow, 1, &key);
+
+	tup = systable_getnext(scan);
+	if (HeapTupleIsValid(tup))
 	{
-		if (strcmp(languageName, ptr->lanname) == 0)
-			return ptr;
+		Form_pg_pltemplate tmpl = (Form_pg_pltemplate) GETSTRUCT(tup);
+		Datum		datum;
+		bool		isnull;
+
+		result = (PLTemplate *) palloc0(sizeof(PLTemplate));
+		result->tmpltrusted = tmpl->tmpltrusted;
+
+		/* Remaining fields are variable-width so we need heap_getattr */
+		datum = heap_getattr(tup, Anum_pg_pltemplate_tmplhandler,
+							 RelationGetDescr(rel), &isnull);
+		if (!isnull)
+			result->tmplhandler =
+				DatumGetCString(DirectFunctionCall1(textout, datum));
+
+		datum = heap_getattr(tup, Anum_pg_pltemplate_tmplvalidator,
+							 RelationGetDescr(rel), &isnull);
+		if (!isnull)
+			result->tmplvalidator =
+				DatumGetCString(DirectFunctionCall1(textout, datum));
+
+		datum = heap_getattr(tup, Anum_pg_pltemplate_tmpllibrary,
+							 RelationGetDescr(rel), &isnull);
+		if (!isnull)
+			result->tmpllibrary =
+				DatumGetCString(DirectFunctionCall1(textout, datum));
+
+		/* Ignore template if handler or library info is missing */
+		if (!result->tmplhandler || !result->tmpllibrary)
+			result = NULL;
 	}
-	return NULL;
+	else
+		result = NULL;
+
+	systable_endscan(scan);
+
+	heap_close(rel, AccessShareLock);
+
+	return result;
+}
+
+
+/*
+ * This just returns TRUE if we have a valid template for a given language
+ */
+bool
+PLTemplateExists(const char *languageName)
+{
+	return (find_language_template(languageName) != NULL);
 }
 
 
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 3b3b792847d..745975a2b56 100644
--- a/src/include/catalog/catversion.h
+++ b/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 1.300 2005/08/15 23:00:14 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.301 2005/09/08 20:07:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200508152
+#define CATALOG_VERSION_NO	200509081
 
 #endif
diff --git a/src/include/catalog/indexing.h b/src/include/catalog/indexing.h
index 0c4c095e40a..bb4ce868fb1 100644
--- a/src/include/catalog/indexing.h
+++ b/src/include/catalog/indexing.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/indexing.h,v 1.90 2005/07/14 05:13:42 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/indexing.h,v 1.91 2005/09/08 20:07:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -93,6 +93,9 @@ DECLARE_UNIQUE_INDEX(pg_auth_members_role_member_index,2694, on pg_auth_members
 DECLARE_UNIQUE_INDEX(pg_auth_members_member_role_index,2695, on pg_auth_members using btree(member oid_ops, roleid oid_ops));
 #define AuthMemMemRoleIndexId	2695
 
+DECLARE_UNIQUE_INDEX(pg_autovacuum_vacrelid_index,1250, on pg_autovacuum using btree(vacrelid oid_ops));
+#define AutovacuumRelidIndexId	1250
+
 DECLARE_UNIQUE_INDEX(pg_cast_oid_index,2660, on pg_cast using btree(oid oid_ops));
 #define CastOidIndexId  2660
 DECLARE_UNIQUE_INDEX(pg_cast_source_target_index,2661, on pg_cast using btree(castsource oid_ops, casttarget oid_ops));
@@ -169,6 +172,9 @@ DECLARE_UNIQUE_INDEX(pg_operator_oid_index,2688, on pg_operator using btree(oid
 DECLARE_UNIQUE_INDEX(pg_operator_oprname_l_r_n_index,2689, on pg_operator using btree(oprname name_ops, oprleft oid_ops, oprright oid_ops, oprnamespace oid_ops));
 #define OperatorNameNspIndexId  2689
 
+DECLARE_UNIQUE_INDEX(pg_pltemplate_name_index,1137, on pg_pltemplate using btree(tmplname name_ops));
+#define PLTemplateNameIndexId  1137
+
 DECLARE_UNIQUE_INDEX(pg_proc_oid_index,2690, on pg_proc using btree(oid oid_ops));
 #define ProcedureOidIndexId  2690
 DECLARE_UNIQUE_INDEX(pg_proc_proname_args_nsp_index,2691, on pg_proc using btree(proname name_ops, proargtypes oidvector_ops, pronamespace oid_ops));
@@ -210,9 +216,6 @@ DECLARE_UNIQUE_INDEX(pg_type_oid_index,2703, on pg_type using btree(oid oid_ops)
 DECLARE_UNIQUE_INDEX(pg_type_typname_nsp_index,2704, on pg_type using btree(typname name_ops, typnamespace oid_ops));
 #define TypeNameNspIndexId  2704
 
-DECLARE_UNIQUE_INDEX(pg_autovacuum_vacrelid_index,1250, on pg_autovacuum using btree(vacrelid oid_ops));
-#define AutovacuumRelidIndexId	1250
-
 /* last step of initialization script: build the indexes declared above */
 BUILD_INDICES
 
diff --git a/src/include/catalog/pg_pltemplate.h b/src/include/catalog/pg_pltemplate.h
new file mode 100644
index 00000000000..3c4ff9f868a
--- /dev/null
+++ b/src/include/catalog/pg_pltemplate.h
@@ -0,0 +1,78 @@
+/*-------------------------------------------------------------------------
+ *
+ * pg_pltemplate.h
+ *	  definition of the system "PL template" relation (pg_pltemplate)
+ *	  along with the relation's initial contents.
+ *
+ *
+ * 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_pltemplate.h,v 1.1 2005/09/08 20:07:42 tgl Exp $
+ *
+ * NOTES
+ *	  the genbki.sh script reads this file and generates .bki
+ *	  information from the DATA() statements.
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PG_PLTEMPLATE_H
+#define PG_PLTEMPLATE_H
+
+/* ----------------
+ *		postgres.h contains the system type definitions and the
+ *		CATALOG(), BKI_BOOTSTRAP and DATA() sugar words so this file
+ *		can be read by both genbki.sh and the C compiler.
+ * ----------------
+ */
+
+/* ----------------
+ *		pg_pltemplate definition.  cpp turns this into
+ *		typedef struct FormData_pg_pltemplate
+ * ----------------
+ */
+#define PLTemplateRelationId	1136
+
+CATALOG(pg_pltemplate,1136) BKI_SHARED_RELATION BKI_WITHOUT_OIDS
+{
+	NameData	tmplname;		/* name of PL */
+	bool		tmpltrusted;	/* PL is trusted? */
+	text		tmplhandler;	/* name of call handler function */
+	text		tmplvalidator;	/* name of validator function, or NULL */
+	text		tmpllibrary;	/* path of shared library */
+	aclitem		tmplacl[1];		/* access privileges for template */
+} FormData_pg_pltemplate;
+
+/* ----------------
+ *		Form_pg_pltemplate corresponds to a pointer to a row with
+ *		the format of pg_pltemplate relation.
+ * ----------------
+ */
+typedef FormData_pg_pltemplate *Form_pg_pltemplate;
+
+/* ----------------
+ *		compiler constants for pg_pltemplate
+ * ----------------
+ */
+#define Natts_pg_pltemplate					6
+#define Anum_pg_pltemplate_tmplname			1
+#define Anum_pg_pltemplate_tmpltrusted		2
+#define Anum_pg_pltemplate_tmplhandler		3
+#define Anum_pg_pltemplate_tmplvalidator	4
+#define Anum_pg_pltemplate_tmpllibrary		5
+#define Anum_pg_pltemplate_tmplacl			6
+
+
+/* ----------------
+ *		initial contents of pg_pltemplate
+ * ----------------
+ */
+
+DATA(insert ( "plpgsql"		t "plpgsql_call_handler" "plpgsql_validator" "$libdir/plpgsql" _null_ ));
+DATA(insert ( "pltcl"		t "pltcl_call_handler" _null_ "$libdir/pltcl" _null_ ));
+DATA(insert ( "pltclu"		f "pltclu_call_handler" _null_ "$libdir/pltcl" _null_ ));
+DATA(insert ( "plperl"		t "plperl_call_handler" "plperl_validator" "$libdir/plperl" _null_ ));
+DATA(insert ( "plperlu"		f "plperl_call_handler" "plperl_validator" "$libdir/plperl" _null_ ));
+DATA(insert ( "plpythonu"	f "plpython_call_handler" _null_ "$libdir/plpython" _null_ ));
+
+#endif   /* PG_PLTEMPLATE_H */
diff --git a/src/include/commands/proclang.h b/src/include/commands/proclang.h
index a446773cd45..7f38a8542ac 100644
--- a/src/include/commands/proclang.h
+++ b/src/include/commands/proclang.h
@@ -15,5 +15,6 @@ extern void CreateProceduralLanguage(CreatePLangStmt *stmt);
 extern void DropProceduralLanguage(DropPLangStmt *stmt);
 extern void DropProceduralLanguageById(Oid langOid);
 extern void RenameLanguage(const char *oldname, const char *newname);
+extern bool PLTemplateExists(const char *languageName);
 
 #endif   /* PROCLANG_H */
diff --git a/src/test/regress/expected/sanity_check.out b/src/test/regress/expected/sanity_check.out
index a6210a1705f..250de98595e 100644
--- a/src/test/regress/expected/sanity_check.out
+++ b/src/test/regress/expected/sanity_check.out
@@ -55,6 +55,7 @@ SELECT relname, relhasindex
  pg_namespace        | t
  pg_opclass          | t
  pg_operator         | t
+ pg_pltemplate       | t
  pg_proc             | t
  pg_rewrite          | t
  pg_shdepend         | t
@@ -67,7 +68,7 @@ SELECT relname, relhasindex
  shighway            | t
  tenk1               | t
  tenk2               | t
-(57 rows)
+(58 rows)
 
 --
 -- another sanity check: every system catalog that has OIDs should have