Remove direct uses of ItemPointer.{ip_blkid,ip_posid}

There are no functional changes here; this simply encapsulates knowledge
of the ItemPointerData struct so that a future patch can change things
without more breakage.

All direct users of ip_blkid and ip_posid are changed to use existing
macros ItemPointerGetBlockNumber and ItemPointerGetOffsetNumber
respectively.  For callers where that's inappropriate (because they
Assert that the itempointer is is valid-looking), add
ItemPointerGetBlockNumberNoCheck and ItemPointerGetOffsetNumberNoCheck,
which lack the assertion but are otherwise identical.

Author: Pavan Deolasee
Discussion: https://postgr.es/m/CABOikdNnFon4cJiL=h1mZH3bgUeU+sWHuU4Yr8AB=j3A2p1GiA@mail.gmail.com

1 files changed, 8 insertions, 7 deletions

diff --git a/src/backend/storage/page/itemptr.c b/src/backend/storage/page/itemptr.c
index 703cbb9c39..b872928f2f 100644
--- a/src/backend/storage/page/itemptr.c
+++ b/src/backend/storage/page/itemptr.c
@@ -52,20 +52,21 @@ int32
 ItemPointerCompare(ItemPointer arg1, ItemPointer arg2)
 {
 	/*
-	 * Don't use ItemPointerGetBlockNumber or ItemPointerGetOffsetNumber here,
-	 * because they assert ip_posid != 0 which might not be true for a
-	 * user-supplied TID.
+	 * Use ItemPointerGet{Offset,Block}NumberNoCheck to avoid asserting
+	 * ip_posid != 0, which may not be true for a user-supplied TID.
 	 */
-	BlockNumber b1 = BlockIdGetBlockNumber(&(arg1->ip_blkid));
-	BlockNumber b2 = BlockIdGetBlockNumber(&(arg2->ip_blkid));
+	BlockNumber b1 = ItemPointerGetBlockNumberNoCheck(arg1);
+	BlockNumber b2 = ItemPointerGetBlockNumberNoCheck(arg2);
 
 	if (b1 < b2)
 		return -1;
 	else if (b1 > b2)
 		return 1;
-	else if (arg1->ip_posid < arg2->ip_posid)
+	else if (ItemPointerGetOffsetNumberNoCheck(arg1) <
+			 ItemPointerGetOffsetNumberNoCheck(arg2))
 		return -1;
-	else if (arg1->ip_posid > arg2->ip_posid)
+	else if (ItemPointerGetOffsetNumberNoCheck(arg1) >
+			 ItemPointerGetOffsetNumberNoCheck(arg2))
 		return 1;
 	else
 		return 0;