Fix bug in wasender's xlogid boundary handling, reported by Erik Rijkers.

LogwrtRqst.Write can be set to non-existent FF log segment, we mustn't
try to send that in XLogSend().

Also fix similar bug in ReadRecord(), which I just introduced in the
ReadRecord() refactoring patch.

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 60d40d4..e8e79b3 100644 (file)
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.362 2010/01/27 15:27:50 heikki Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.363 2010/01/27 16:41:09 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -3574,6 +3574,12 @@ ReadRecord(XLogRecPtr *RecPtr, int emode_arg, bool fetching_ckpt)
                        NextLogPage(tmpRecPtr);
                        /* We will account for page header size below */
                }
+
+               if (tmpRecPtr.xrecoff >= XLogFileSize)
+               {
+                       (tmpRecPtr.xlogid)++;
+                       tmpRecPtr.xrecoff = 0;
+               }
        }
        else
        {

diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index a10dc3d..0eb074f 100644 (file)
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -30,7 +30,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/replication/walsender.c,v 1.3 2010/01/21 08:19:57 heikki Exp $
+ *       $PostgreSQL: pgsql/src/backend/replication/walsender.c,v 1.4 2010/01/27 16:41:09 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -610,8 +610,8 @@ XLogSend(StringInfo outMsg)
                return true;
 
        /*
-        * We gather multiple records together by issuing just one read() of
-        * a suitable size, and send them as one CopyData message. Repeat
+        * We gather multiple records together by issuing just one XLogRead()
+        * of a suitable size, and send them as one CopyData message. Repeat
         * until we've sent everything we can.
         */
        while (XLByteLT(sentPtr, SendRqstPtr))
@@ -628,11 +628,21 @@ XLogSend(StringInfo outMsg)
                 * The rounding is not only for performance reasons. Walreceiver
                 * relies on the fact that we never split a WAL record across two
                 * messages. Since a long WAL record is split at page boundary into
-                * continuation records, page boundary is alwayssafe cut-off point.
+                * continuation records, page boundary is always a safe cut-off point.
                 * We also assume that SendRqstPtr never points in the middle of a
                 * WAL record.
                 */
                startptr = sentPtr;
+               if (startptr.xrecoff >= XLogFileSize)
+               {
+                       /*
+                        * crossing a logid boundary, skip the non-existent last log
+                        * segment in previous logical log file.
+                        */
+                       startptr.xlogid += 1;
+                       startptr.xrecoff = 0;
+               }
+
                endptr = startptr;
                XLByteAdvance(endptr, MAX_SEND_SIZE);
                /* round down to page boundary. */