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diff --git a/src/include/access/xloginsert.h b/src/include/access/xloginsert.h
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+++ b/src/include/access/xloginsert.h
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+/*
+ * xloginsert.h
+ *
+ * Functions for generating WAL records
+ *
+ * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/access/xloginsert.h
+ */
+#ifndef XLOGINSERT_H
+#define XLOGINSERT_H
+
+#include "access/rmgr.h"
+#include "access/xlogdefs.h"
+#include "storage/block.h"
+#include "storage/buf.h"
+#include "storage/relfilenode.h"
+
+/*
+ * The rmgr data to be written by XLogInsert() is defined by a chain of
+ * one or more XLogRecData structs.  (Multiple structs would be used when
+ * parts of the source data aren't physically adjacent in memory, or when
+ * multiple associated buffers need to be specified.)
+ *
+ * If buffer is valid then XLOG will check if buffer must be backed up
+ * (ie, whether this is first change of that page since last checkpoint).
+ * If so, the whole page contents are attached to the XLOG record, and XLOG
+ * sets XLR_BKP_BLOCK(N) bit in xl_info.  Note that the buffer must be pinned
+ * and exclusive-locked by the caller, so that it won't change under us.
+ * NB: when the buffer is backed up, we DO NOT insert the data pointed to by
+ * this XLogRecData struct into the XLOG record, since we assume it's present
+ * in the buffer.  Therefore, rmgr redo routines MUST pay attention to
+ * XLR_BKP_BLOCK(N) to know what is actually stored in the XLOG record.
+ * The N'th XLR_BKP_BLOCK bit corresponds to the N'th distinct buffer
+ * value (ignoring InvalidBuffer) appearing in the rdata chain.
+ *
+ * When buffer is valid, caller must set buffer_std to indicate whether the
+ * page uses standard pd_lower/pd_upper header fields.  If this is true, then
+ * XLOG is allowed to omit the free space between pd_lower and pd_upper from
+ * the backed-up page image.  Note that even when buffer_std is false, the
+ * page MUST have an LSN field as its first eight bytes!
+ *
+ * Note: data can be NULL to indicate no rmgr data associated with this chain
+ * entry.  This can be sensible (ie, not a wasted entry) if buffer is valid.
+ * The implication is that the buffer has been changed by the operation being
+ * logged, and so may need to be backed up, but the change can be redone using
+ * only information already present elsewhere in the XLOG entry.
+ */
+typedef struct XLogRecData
+{
+	char	   *data;			/* start of rmgr data to include */
+	uint32		len;			/* length of rmgr data to include */
+	Buffer		buffer;			/* buffer associated with data, if any */
+	bool		buffer_std;		/* buffer has standard pd_lower/pd_upper */
+	struct XLogRecData *next;	/* next struct in chain, or NULL */
+} XLogRecData;
+
+extern XLogRecPtr XLogInsert(RmgrId rmid, uint8 info, XLogRecData *rdata);
+extern XLogRecPtr log_newpage(RelFileNode *rnode, ForkNumber forkNum,
+			BlockNumber blk, char *page, bool page_std);
+extern XLogRecPtr log_newpage_buffer(Buffer buffer, bool page_std);
+extern XLogRecPtr XLogSaveBufferForHint(Buffer buffer, bool buffer_std);
+extern bool XLogCheckBufferNeedsBackup(Buffer buffer);
+
+#endif   /* XLOGINSERT_H */