Log the correct ending timestamp in recovery_target_xid mode.

When ending recovery based on recovery_target_xid matching with
recovery_target_inclusive = off, we printed an incorrect timestamp
(always 2000-01-01) in the "recovery stopping before ... transaction"
log message.  This is a consequence of sloppy refactoring in
c945af80c: the code to fetch recordXtime out of the commit/abort
record used to be executed unconditionally, but it was changed
to get called only in the RECOVERY_TARGET_TIME case.  We need only
flip the order of operations to restore the intended behavior.

Per report from Torsten Förtsch.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/CAKkG4_kUevPqbmyOfLajx7opAQk6Cvwkvx0HRcFjSPfRPTXanA@mail.gmail.com

diff --git a/src/backend/access/transam/xlogrecovery.c b/src/backend/access/transam/xlogrecovery.c
index 5e657853066b39b3233be036ae6458354194b996..c14d1f3ef63b65cc917c34223160f3c25d9e54cb 100644 (file)
--- a/src/backend/access/transam/xlogrecovery.c
+++ b/src/backend/access/transam/xlogrecovery.c
@@ -2548,8 +2548,13 @@ recoveryStopsBefore(XLogReaderState *record)
                stopsHere = (recordXid == recoveryTargetXid);
        }
 
-       if (recoveryTarget == RECOVERY_TARGET_TIME &&
-               getRecordTimestamp(record, &recordXtime))
+       /*
+        * Note: we must fetch recordXtime regardless of recoveryTarget setting.
+        * We don't expect getRecordTimestamp ever to fail, since we already know
+        * this is a commit or abort record; but test its result anyway.
+        */
+       if (getRecordTimestamp(record, &recordXtime) &&
+               recoveryTarget == RECOVERY_TARGET_TIME)
        {
                /*
                 * There can be many transactions that share the same commit time, so