Fix uninitialized value in pgstatindex leading to invalid values being

reported in some cases.  Report and patch from Tatsuhito Kasahara.

Also fix a couple of other bugs I noticed in skimming the surrounding code.

diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index d684a3e055ee14fd757e56b3a6ff16837eade640..2982ceaf50645fc26ff77b933779127ced3db8c1 100644 (file)
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -139,7 +139,7 @@ typedef struct BTIndexStat
  * Collect statistics of single b-tree leaf page
  * -------------------------------------------------
  */
-static bool
+static void
 GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
 {
        Page            page = BufferGetPage(buffer);
@@ -154,6 +154,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
        stat->max_avail = BLCKSZ - (BLCKSZ - phdr->pd_special + SizeOfPageHeaderData);
 
        stat->dead_items = stat->live_items = 0;
+       stat->fragments = 0;
 
        stat->page_size = PageGetPageSize(page);
 
@@ -161,7 +162,8 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
        if (P_ISDELETED(opaque))
        {
                stat->type = 'd';
-               return true;
+               stat->btpo.xact = opaque->btpo.xact;
+               return;
        }
        else if (P_IGNORE(opaque))
                stat->type = 'e';
@@ -175,10 +177,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
        /* btpage opaque data */
        stat->btpo_prev = opaque->btpo_prev;
        stat->btpo_next = opaque->btpo_next;
-       if (P_ISDELETED(opaque))
-               stat->btpo.xact = opaque->btpo.xact;
-       else
-               stat->btpo.level = opaque->btpo.level;
+       stat->btpo.level = opaque->btpo.level;
        stat->btpo_flags = opaque->btpo_flags;
        stat->btpo_cycleid = opaque->btpo_cycleid;
 
@@ -187,7 +186,6 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
         * it means a fragmentation.
         *----------------------------------------------
         */
-       stat->fragments = 0;
        if (stat->type == 'l')
        {
                if (opaque->btpo_next != P_NONE && opaque->btpo_next < blkno)
@@ -216,8 +214,6 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat * stat)
                stat->avg_item_size = item_size / (stat->live_items + stat->dead_items);
        else
                stat->avg_item_size = 0;
-
-       return true;
 }
 
 
@@ -338,8 +334,7 @@ pgstatindex(PG_FUNCTION_ARGS)
                int                     j;
                char       *values[PGSTATINDEX_NCOLUMNS];
 
-               HeapTupleData tupleData;
-               HeapTuple       tuple = &tupleData;
+               HeapTuple       tuple;
 
                tupleDesc = RelationNameGetTupleDesc(PGSTATINDEX_TYPE);