Redefine the lp_flags field of item pointers as having four states, rather

than two independent bits (one of which was never used in heap pages anyway,
or at least hadn't been in a very long time).  This gives us flexibility to
add the HOT notions of redirected and dead item pointers without requiring
anything so klugy as magic values of lp_off and lp_len.  The state values
are chosen so that for the states currently in use (pre-HOT) there is no
change in the physical representation.

4 files changed, 14 insertions, 14 deletions

diff --git a/src/backend/commands/sequence.c b/src/backend/commands/sequence.c
index cb2a1380ca..73024a7e70 100644
--- a/src/backend/commands/sequence.c
+++ b/src/backend/commands/sequence.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/sequence.c,v 1.144 2007/09/05 18:10:47 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/sequence.c,v 1.145 2007/09/12 22:10:26 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -936,7 +936,7 @@ read_info(SeqTable elm, Relation rel, Buffer *buf)
 			 RelationGetRelationName(rel), sm->magic);
 
 	lp = PageGetItemId(page, FirstOffsetNumber);
-	Assert(ItemIdIsUsed(lp));
+	Assert(ItemIdIsNormal(lp));
 	tuple.t_data = (HeapTupleHeader) PageGetItem((Page) page, lp);
 
 	seq = (Form_pg_sequence) GETSTRUCT(&tuple);
@@ -1281,7 +1281,7 @@ seq_redo(XLogRecPtr lsn, XLogRecord *record)
 	itemsz = record->xl_len - sizeof(xl_seq_rec);
 	itemsz = MAXALIGN(itemsz);
 	if (PageAddItem(page, (Item) item, itemsz,
-					FirstOffsetNumber, LP_USED) == InvalidOffsetNumber)
+					FirstOffsetNumber, false) == InvalidOffsetNumber)
 		elog(PANIC, "seq_redo: failed to add item to page");
 
 	PageSetLSN(page, lsn);
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index afcdaa5e91..5d8b6aa168 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.218 2007/08/15 21:39:50 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.219 2007/09/12 22:10:26 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1826,7 +1826,7 @@ ltrmark:;
 		dp = (PageHeader) BufferGetPage(buffer);
 		lp = PageGetItemId(dp, ItemPointerGetOffsetNumber(tid));
 
-		Assert(ItemIdIsUsed(lp));
+		Assert(ItemIdIsNormal(lp));
 
 		tuple.t_data = (HeapTupleHeader) PageGetItem((Page) dp, lp);
 		tuple.t_len = ItemIdGetLength(lp);
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 89ddeedbea..f9b9423534 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.357 2007/09/08 20:31:14 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.358 2007/09/12 22:10:26 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1522,7 +1522,7 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
 
 				/* mark it unused on the temp page */
 				lpp = PageGetItemId(tempPage, offnum);
-				lpp->lp_flags &= ~LP_USED;
+				ItemIdSetUnused(lpp);
 
 				vacpage->offsets[vacpage->offsets_free++] = offnum;
 				tups_vacuumed += 1;
@@ -1558,7 +1558,7 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
 		{
 			/* Just use current available space */
 			vacpage->free = PageGetFreeSpaceWithFillFactor(onerel, page);
-			/* Need to reap the page if it has ~LP_USED line pointers */
+			/* Need to reap the page if it has LP_UNUSED line pointers */
 			do_reap = (vacpage->offsets_free > 0);
 		}
 
@@ -2582,7 +2582,7 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
 				if (HeapTupleHeaderGetXvac(htup) != myXID)
 					elog(ERROR, "invalid XVAC in tuple header");
 
-				itemid->lp_flags &= ~LP_USED;
+				ItemIdSetUnused(itemid);
 				num_tuples++;
 			}
 			Assert(vacpage->offsets_free == num_tuples);
@@ -2714,7 +2714,7 @@ move_chain_tuple(Relation rel,
 	newtup.t_data->t_infomask |= HEAP_MOVED_IN;
 	HeapTupleHeaderSetXvac(newtup.t_data, myXID);
 	newoff = PageAddItem(dst_page, (Item) newtup.t_data, tuple_len,
-						 InvalidOffsetNumber, LP_USED);
+						 InvalidOffsetNumber, false);
 	if (newoff == InvalidOffsetNumber)
 		elog(PANIC, "failed to add item with len = %lu to page %u while moving tuple chain",
 			 (unsigned long) tuple_len, dst_vacpage->blkno);
@@ -2819,7 +2819,7 @@ move_plain_tuple(Relation rel,
 
 	/* add tuple to the page */
 	newoff = PageAddItem(dst_page, (Item) newtup.t_data, tuple_len,
-						 InvalidOffsetNumber, LP_USED);
+						 InvalidOffsetNumber, false);
 	if (newoff == InvalidOffsetNumber)
 		elog(PANIC, "failed to add item with len = %lu to page %u (free space %lu, nusd %u, noff %u)",
 			 (unsigned long) tuple_len,
@@ -3033,7 +3033,7 @@ vacuum_page(Relation onerel, Buffer buffer, VacPage vacpage)
 	for (i = 0; i < vacpage->offsets_free; i++)
 	{
 		itemid = PageGetItemId(page, vacpage->offsets[i]);
-		itemid->lp_flags &= ~LP_USED;
+		ItemIdSetUnused(itemid);
 	}
 
 	uncnt = PageRepairFragmentation(page, unused);
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 0552c3e0ae..3dbd17de58 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -36,7 +36,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.94 2007/09/12 02:05:48 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.95 2007/09/12 22:10:26 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -642,7 +642,7 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer,
 			break;				/* past end of tuples for this block */
 		toff = ItemPointerGetOffsetNumber(&vacrelstats->dead_tuples[tupindex]);
 		itemid = PageGetItemId(page, toff);
-		itemid->lp_flags &= ~LP_USED;
+		ItemIdSetUnused(itemid);
 	}
 
 	uncnt = PageRepairFragmentation(page, unused);