Combine index_info and find_secondary_indexes into a single routine that

returns a list of RelOptInfos, eliminating the need for static state
in index_info.  That static state was a direct cause of coredumps; if
anything decided to elog(ERROR) partway through an index_info search of
pg_index, the next query would try to close a scan pointer that was
pointing at no-longer-valid memory.  Another example of the reasons to
avoid static state variables...

src/backend/optimizer/util/indexnode.c

@@ -7,21 +7,16 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/Attic/indexnode.c,v 1.20 1999/08/16 02:17:57 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/Attic/indexnode.c,v 1.21 1999/11/21 23:25:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
-#include <sys/types.h>
-
 #include "postgres.h"
 
-
 #include "optimizer/pathnode.h"
 #include "optimizer/plancat.h"
 
 
-static List *find_secondary_index(Query *root, Oid relid);
-
 /*
  * find_relation_indices
  *	  Returns a list of index nodes containing appropriate information for
@@ -32,56 +27,7 @@ List *
 find_relation_indices(Query *root, RelOptInfo *rel)
 {
 	if (rel->indexed)
-		return find_secondary_index(root, lfirsti(rel->relids));
+		return find_secondary_indexes(root, lfirsti(rel->relids));
 	else
 		return NIL;
 }
-
-/*
- * find_secondary_index
- *	  Creates a list of RelOptInfo nodes containing information for each
- *	  secondary index defined on a relation by searching through the index
- *	  catalog.
- *
- * 'relid' is the OID of the relation for which indices are being located
- *
- * Returns a list of new index RelOptInfo nodes.
- */
-static List *
-find_secondary_index(Query *root, Oid relid)
-{
-	IdxInfoRetval indexinfo;
-	List	   *indexes = NIL;
-	bool		first = true;
-
-	while (index_info(root, first, relid, &indexinfo))
-	{
-		RelOptInfo *indexnode = makeNode(RelOptInfo);
-
-		indexnode->relids = lconsi(indexinfo.relid, NIL);
-		indexnode->relam = indexinfo.relam;
-		indexnode->pages = indexinfo.pages;
-		indexnode->tuples = indexinfo.tuples;
-		indexnode->classlist = indexinfo.classlist;
-		indexnode->indexkeys = indexinfo.indexkeys;
-		indexnode->ordering = indexinfo.orderOprs;
-		indexnode->indproc = indexinfo.indproc;
-		indexnode->indpred = (List *) indexinfo.indpred;
-
-		indexnode->indexed = false;		/* not indexed itself */
-		indexnode->size = 0;
-		indexnode->width = 0;
-		indexnode->targetlist = NIL;
-		indexnode->pathlist = NIL;
-		indexnode->cheapestpath = NULL;
-		indexnode->pruneable = true;
-		indexnode->restrictinfo = NIL;
-		indexnode->joininfo = NIL;
-		indexnode->innerjoin = NIL;
-
-		indexes = lcons(indexnode, indexes);
-		first = false;
-	}
-
-	return indexes;
-}

src/include/optimizer/plancat.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: plancat.h,v 1.13 1999/07/25 23:07:23 tgl Exp $
+ * $Id: plancat.h,v 1.14 1999/11/21 23:25:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -15,32 +15,11 @@
 
 #include "nodes/parsenodes.h"
 
-/*
- * transient data structure to hold return value of index_info. Note that
- * indexkeys, orderOprs and classlist is "null-terminated".
- */
-typedef struct IdxInfoRetval
-{
-	Oid			relid;			/* OID of the index relation (not the OID
-								 * of the relation being indexed) */
-	Oid			relam;			/* OID of the pg_am of this index */
-	int			pages;			/* number of pages in the index relation */
-	int			tuples;			/* number of tuples in the index relation */
-	int		   *indexkeys;		/* keys over which we're indexing */
-	Oid		   *orderOprs;		/* operators used for ordering purposes */
-	Oid		   *classlist;		/* classes of AM operators */
-	Oid			indproc;
-	Node	   *indpred;
-} IdxInfoRetval;
-
-
-extern void relation_info(Query *root,
-			  Oid relid,
-			  bool *hashindex, int *pages,
-			  int *tuples);
-
-extern bool index_info(Query *root,
-		   bool first, int relid, IdxInfoRetval *info);
+
+extern void relation_info(Query *root, Index relid,
+						  bool *hasindex, int *pages, int *tuples);
+
+extern List *find_secondary_indexes(Query *root, Index relid);
 
 extern Cost restriction_selectivity(Oid functionObjectId,
 						Oid operatorObjectId,