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diff --git a/src/include/access/xlogdefs.h b/src/include/access/xlogdefs.h
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+/*
+ * xlogdefs.h
+ *
+ * Postgres write-ahead log manager record pointer and
+ * timeline number definitions
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/access/xlogdefs.h
+ */
+#ifndef XLOG_DEFS_H
+#define XLOG_DEFS_H
+
+#include <fcntl.h> /* need open() flags */
+
+/*
+ * Pointer to a location in the XLOG. These pointers are 64 bits wide,
+ * because we don't want them ever to overflow.
+ */
+typedef uint64 XLogRecPtr;
+
+/*
+ * Zero is used indicate an invalid pointer. Bootstrap skips the first possible
+ * WAL segment, initializing the first WAL page at WAL segment size, so no XLOG
+ * record can begin at zero.
+ */
+#define InvalidXLogRecPtr 0
+#define XLogRecPtrIsInvalid(r) ((r) == InvalidXLogRecPtr)
+
+/*
+ * First LSN to use for "fake" LSNs.
+ *
+ * Values smaller than this can be used for special per-AM purposes.
+ */
+#define FirstNormalUnloggedLSN ((XLogRecPtr) 1000)
+
+/*
+ * Handy macro for printing XLogRecPtr in conventional format, e.g.,
+ *
+ * printf("%X/%X", LSN_FORMAT_ARGS(lsn));
+ */
+#define LSN_FORMAT_ARGS(lsn) (AssertVariableIsOfTypeMacro((lsn), XLogRecPtr), (uint32) ((lsn) >> 32)), ((uint32) (lsn))
+
+/*
+ * XLogSegNo - physical log file sequence number.
+ */
+typedef uint64 XLogSegNo;
+
+/*
+ * TimeLineID (TLI) - identifies different database histories to prevent
+ * confusion after restoring a prior state of a database installation.
+ * TLI does not change in a normal stop/restart of the database (including
+ * crash-and-recover cases); but we must assign a new TLI after doing
+ * a recovery to a prior state, a/k/a point-in-time recovery. This makes
+ * the new WAL logfile sequence we generate distinguishable from the
+ * sequence that was generated in the previous incarnation.
+ */
+typedef uint32 TimeLineID;
+
+/*
+ * Replication origin id - this is located in this file to avoid having to
+ * include origin.h in a bunch of xlog related places.
+ */
+typedef uint16 RepOriginId;
+
+/*
+ * This chunk of hackery attempts to determine which file sync methods
+ * are available on the current platform, and to choose an appropriate
+ * default method. We assume that fsync() is always available, and that
+ * configure determined whether fdatasync() is.
+ */
+#if defined(O_SYNC)
+#define OPEN_SYNC_FLAG O_SYNC
+#elif defined(O_FSYNC)
+#define OPEN_SYNC_FLAG O_FSYNC
+#endif
+
+#if defined(O_DSYNC)
+#if defined(OPEN_SYNC_FLAG)
+/* O_DSYNC is distinct? */
+#if O_DSYNC != OPEN_SYNC_FLAG
+#define OPEN_DATASYNC_FLAG O_DSYNC
+#endif
+#else /* !defined(OPEN_SYNC_FLAG) */
+/* Win32 only has O_DSYNC */
+#define OPEN_DATASYNC_FLAG O_DSYNC
+#endif
+#endif
+
+#if defined(PLATFORM_DEFAULT_SYNC_METHOD)
+#define DEFAULT_SYNC_METHOD PLATFORM_DEFAULT_SYNC_METHOD
+#elif defined(OPEN_DATASYNC_FLAG)
+#define DEFAULT_SYNC_METHOD SYNC_METHOD_OPEN_DSYNC
+#elif defined(HAVE_FDATASYNC)
+#define DEFAULT_SYNC_METHOD SYNC_METHOD_FDATASYNC
+#else
+#define DEFAULT_SYNC_METHOD SYNC_METHOD_FSYNC
+#endif
+
+#endif /* XLOG_DEFS_H */