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 7ba8def..a562143 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;
 }