Allow extracting and parsing of reloptions from a bare pg_class tuple, and

refactor the relcache code that used to do that.  This allows other callers
(particularly autovacuum) to do the same without necessarily having to open
and lock a table.

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 46e2d00bc6480622105d94ef485c6dec1acec83d..105514be9ddf9140ae1bcaba68fc2a20e7f1ea8c 100644 (file)
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/access/common/reloptions.c,v 1.18 2009/01/12 21:02:14 alvherre Exp $
+ *   $PostgreSQL: pgsql/src/backend/access/common/reloptions.c,v 1.19 2009/01/26 19:41:06 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -558,6 +558,53 @@ untransformRelOptions(Datum options)
    return result;
 }
 
+/*
+ * Extract and parse reloptions from a pg_class tuple.
+ *
+ * This is a low-level routine, expected to be used by relcache code and
+ * callers that do not have a table's relcache entry (e.g. autovacuum).  For
+ * other uses, consider grabbing the rd_options pointer from the relcache entry
+ * instead.
+ *
+ * tupdesc is pg_class' tuple descriptor.  amoptions is the amoptions regproc
+ * in the case of the tuple corresponding to an index, or InvalidOid otherwise.
+ */
+bytea *
+extractRelOptions(HeapTuple tuple, TupleDesc tupdesc, Oid amoptions)
+{
+   bytea  *options;
+   bool    isnull;
+   Datum   datum;
+   Form_pg_class   classForm;
+
+   datum = fastgetattr(tuple,
+                       Anum_pg_class_reloptions,
+                       tupdesc,
+                       &isnull);
+   if (isnull)
+       return NULL;
+
+   classForm = (Form_pg_class) GETSTRUCT(tuple);
+
+   /* Parse into appropriate format; don't error out here */
+   switch (classForm->relkind)
+   {
+       case RELKIND_RELATION:
+       case RELKIND_TOASTVALUE:
+       case RELKIND_UNCATALOGED:
+           options = heap_reloptions(classForm->relkind, datum, false);
+           break;
+       case RELKIND_INDEX:
+           options = index_reloptions(amoptions, datum, false);
+           break;
+       default:
+           Assert(false);      /* can't get here */
+           options = NULL;     /* keep compiler quiet */
+           break;
+   }
+   
+   return options;
+}
 
 /*
  * Interpret reloptions that are given in text-array format.

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index ecfe59e3a8c83caa9e503d55561d0fb31c92a60d..1cac2765164bc0370d5283520aafaeaa98d0466e 100644 (file)
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.282 2009/01/22 20:16:06 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.283 2009/01/26 19:41:06 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -351,8 +351,6 @@ AllocateRelationDesc(Relation relation, Form_pg_class relp)
 static void
 RelationParseRelOptions(Relation relation, HeapTuple tuple)
 {
-   Datum       datum;
-   bool        isnull;
    bytea      *options;
 
    relation->rd_options = NULL;
@@ -374,31 +372,10 @@ RelationParseRelOptions(Relation relation, HeapTuple tuple)
     * we might not have any other for pg_class yet (consider executing this
     * code for pg_class itself)
     */
-   datum = fastgetattr(tuple,
-                       Anum_pg_class_reloptions,
-                       GetPgClassDescriptor(),
-                       &isnull);
-   if (isnull)
-       return;
-
-   /* Parse into appropriate format; don't error out here */
-   switch (relation->rd_rel->relkind)
-   {
-       case RELKIND_RELATION:
-       case RELKIND_TOASTVALUE:
-       case RELKIND_UNCATALOGED:
-           options = heap_reloptions(relation->rd_rel->relkind, datum,
-                                     false);
-           break;
-       case RELKIND_INDEX:
-           options = index_reloptions(relation->rd_am->amoptions, datum,
-                                      false);
-           break;
-       default:
-           Assert(false);      /* can't get here */
-           options = NULL;     /* keep compiler quiet */
-           break;
-   }
+   options = extractRelOptions(tuple,
+                               GetPgClassDescriptor(),
+                               relation->rd_rel->relkind == RELKIND_INDEX ?
+                               relation->rd_am->amoptions : InvalidOid);
 
    /* Copy parsed data into CacheMemoryContext */
    if (options)

diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index 56f7589c1a7601ef4666aabdf76e809d6e0045ef..1c23b3f004df70226ec3cdc9a86eecb29a5b0e00 100644 (file)
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -11,13 +11,14 @@
  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/access/reloptions.h,v 1.10 2009/01/12 21:02:15 alvherre Exp $
+ * $PostgreSQL: pgsql/src/include/access/reloptions.h,v 1.11 2009/01/26 19:41:06 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
 #ifndef RELOPTIONS_H
 #define RELOPTIONS_H
 
+#include "access/htup.h"
 #include "nodes/pg_list.h"
 
 /* types supported by reloptions */
@@ -241,6 +242,8 @@ extern void add_string_reloption(int kind, char *name, char *desc,
 extern Datum transformRelOptions(Datum oldOptions, List *defList,
                    bool ignoreOids, bool isReset);
 extern List *untransformRelOptions(Datum options);
+extern bytea *extractRelOptions(HeapTuple tuple, TupleDesc tupdesc,
+                 Oid amoptions);
 extern relopt_value *parseRelOptions(Datum options, bool validate,
                relopt_kind kind, int *numrelopts);
 extern void *allocateReloptStruct(Size base, relopt_value *options,