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diff --git a/src/backend/storage/itemptr.h b/src/backend/storage/itemptr.h
new file mode 100644
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+++ b/src/backend/storage/itemptr.h
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+/*-------------------------------------------------------------------------
+ *
+ * itemptr.h--
+ *    POSTGRES disk item pointer definitions.
+ *
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ * $Id: itemptr.h,v 1.1.1.1 1996/07/09 06:21:53 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef	ITEMPTR_H
+#define ITEMPTR_H
+
+#include "c.h"
+#include "storage/block.h"
+#include "storage/off.h"
+#include "storage/itemid.h"
+
+/*
+ * ItemPointer:
+ *
+ * this is a pointer to an item on another disk page in the same file.
+ * blkid tells us which block, posid tells us which entry in the linp
+ * (ItemIdData) array we want.
+ */
+typedef struct ItemPointerData {
+    BlockIdData		ip_blkid;
+    OffsetNumber	ip_posid;
+} ItemPointerData;
+
+typedef ItemPointerData	*ItemPointer;
+
+/* ----------------
+ *	support macros
+ * ----------------
+ */
+
+/*
+ * ItemPointerIsValid --
+ *	True iff the disk item pointer is not NULL.
+ */
+#define ItemPointerIsValid(pointer) \
+    ((bool) (PointerIsValid(pointer) && ((pointer)->ip_posid != 0)))
+
+/*
+ * ItemPointerGetBlockNumber --
+ *	Returns the block number of a disk item pointer.
+ */
+#define ItemPointerGetBlockNumber(pointer) \
+    (AssertMacro(ItemPointerIsValid(pointer)) ? \
+     BlockIdGetBlockNumber(&(pointer)->ip_blkid) : (BlockNumber) 0)
+
+/*
+ * ItemPointerGetOffsetNumber --
+ *	Returns the offset number of a disk item pointer.
+ */
+#define ItemPointerGetOffsetNumber(pointer) \
+    (AssertMacro(ItemPointerIsValid(pointer)) ? \
+     (pointer)->ip_posid : \
+     InvalidOffsetNumber)
+
+/*
+ * ItemPointerSet --
+ *	Sets a disk item pointer to the specified block and offset.
+ */
+#define ItemPointerSet(pointer, blockNumber, offNum) \
+    Assert(PointerIsValid(pointer)); \
+    BlockIdSet(&((pointer)->ip_blkid), blockNumber); \
+    (pointer)->ip_posid = offNum
+
+/*
+ * ItemPointerSetBlockNumber --
+ *	Sets a disk item pointer to the specified block.
+ */
+#define ItemPointerSetBlockNumber(pointer, blockNumber) \
+    Assert(PointerIsValid(pointer)); \
+    BlockIdSet(&((pointer)->ip_blkid), blockNumber)
+
+/*
+ * ItemPointerSetOffsetNumber --
+ *	Sets a disk item pointer to the specified offset.
+ */
+#define ItemPointerSetOffsetNumber(pointer, offsetNumber) \
+    AssertMacro(PointerIsValid(pointer)); \
+    (pointer)->ip_posid = (offsetNumber)
+
+/*
+ * ItemPointerCopy --
+ *	Copies the contents of one disk item pointer to another.
+ */
+#define ItemPointerCopy(fromPointer, toPointer) \
+    Assert(PointerIsValid(toPointer)); \
+    Assert(PointerIsValid(fromPointer)); \
+    *(toPointer) = *(fromPointer)
+
+/*
+ * ItemPointerSetInvalid --
+ *	Sets a disk item pointer to be invalid.
+ */
+#define ItemPointerSetInvalid(pointer) \
+    Assert(PointerIsValid(pointer)); \
+    BlockIdSet(&((pointer)->ip_blkid), InvalidBlockNumber); \
+    (pointer)->ip_posid = InvalidOffsetNumber
+
+/* ----------------
+ *	externs
+ * ----------------
+ */
+
+extern bool ItemPointerEquals(ItemPointer pointer1, ItemPointer pointer2);
+
+#endif	/* ITEMPTR_H */
+