Done.

o overwriting an existing lobj now works
o 8KB garbage block always inserted problem is fixed

Tatsuo Ishii

diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c
index 7ba8deff9f00372e3800dfb57b3340c5008cabc7..a56214356ac0f8d43331befe6af18bb8a39f5c2a 100644 (file)
--- a/src/backend/storage/large_object/inv_api.c
+++ b/src/backend/storage/large_object/inv_api.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.50 1999/02/22 16:46:43 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.51 1999/03/14 16:08:17 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -72,7 +72,10 @@
  *     For subsequent notes, [PA] is Pascal André <andre@via.ecp.fr>
  */
 
-#define IFREESPC(p)        (PageGetFreeSpace(p) - sizeof(HeapTupleData) - sizeof(struct varlena) - sizeof(int32))
+#define IFREESPC(p)        (PageGetFreeSpace(p) - \
+                DOUBLEALIGN(offsetof(HeapTupleHeaderData,t_bits)) - \
+                DOUBLEALIGN(sizeof(struct varlena) + sizeof(int32)) - \
+                sizeof(double))
 #define IMAXBLK            8092
 #define IMINBLK            512
 
@@ -623,24 +626,25 @@ inv_fetchtup(LargeObjectDesc *obj_desc, HeapTuple tuple, Buffer *buffer)
        || obj_desc->offset < obj_desc->lowbyte
        || !ItemPointerIsValid(&(obj_desc->htid)))
    {
+       ScanKeyData skey;
+
+       ScanKeyEntryInitialize(&skey, 0x0, 1, F_INT4GE,
+                      Int32GetDatum(obj_desc->offset));
 
        /* initialize scan key if not done */
        if (obj_desc->iscan == (IndexScanDesc) NULL)
        {
-           ScanKeyData skey;
-
            /*
             * As scan index may be prematurely closed (on commit), we
             * must use object current offset (was 0) to reinitialize the
             * entry [ PA ].
             */
-           ScanKeyEntryInitialize(&skey, 0x0, 1, F_INT4GE,
-                                  Int32GetDatum(obj_desc->offset));
            obj_desc->iscan = index_beginscan(obj_desc->index_r,
                                (bool) 0, (uint16) 1,
                                &skey);
-       }
-
+       } else {
+           index_rescan(obj_desc->iscan, false, &skey);
+           }
        do
        {
            res = index_getnext(obj_desc->iscan, ForwardScanDirection);
@@ -673,6 +677,9 @@ inv_fetchtup(LargeObjectDesc *obj_desc, HeapTuple tuple, Buffer *buffer)
    {
        tuple->t_self = obj_desc->htid;
        heap_fetch(obj_desc->heap_r, SnapshotNow, tuple, buffer);
+       if (tuple->t_data == NULL) {
+           elog(ERROR, "inv_fetchtup: heap_fetch failed");
+       }
    }
 
    /*
@@ -744,12 +751,15 @@ inv_wrnew(LargeObjectDesc *obj_desc, char *buf, int nbytes)
 
    nblocks = RelationGetNumberOfBlocks(hr);
 
-   if (nblocks > 0)
+   if (nblocks > 0) {
        buffer = ReadBuffer(hr, nblocks - 1);
-   else
+       page = BufferGetPage(buffer);
+   }
+   else {
        buffer = ReadBuffer(hr, P_NEW);
-
-   page = BufferGetPage(buffer);
+       page = BufferGetPage(buffer);
+       PageInit(page, BufferGetPageSize(buffer), 0);
+   }
 
    /*
     * If the last page is too small to hold all the data, and it's too
@@ -864,12 +874,16 @@ inv_wrold(LargeObjectDesc *obj_desc,
 
        nblocks = RelationGetNumberOfBlocks(hr);
 
-       if (nblocks > 0)
+       if (nblocks > 0) {
            newbuf = ReadBuffer(hr, nblocks - 1);
-       else
+           newpage = BufferGetPage(newbuf);
+       }
+       else {
            newbuf = ReadBuffer(hr, P_NEW);
+           newpage = BufferGetPage(newbuf);
+           PageInit(newpage, BufferGetPageSize(newbuf), 0);
+       }
 
-       newpage = BufferGetPage(newbuf);
        freespc = IFREESPC(newpage);
 
        /*
@@ -974,6 +988,9 @@ inv_wrold(LargeObjectDesc *obj_desc,
    if (newbuf != buffer)
        WriteBuffer(newbuf);
 
+   /* Tuple id is no longer valid */
+   ItemPointerSetInvalid(&(obj_desc->htid));
+
    /* done */
    return nwritten;
 }