postgres.git / summary / log / commit / refs

commit    7ef311eb426b2ab01831cc5f1502a5b838c8cdd3
Author:   Alvaro Herrera <alvherre@alvh.no-ip.org>
Date:     Tue Jan 05 20:25:12 2016 +0000

    Make pg_receivexlog silent with 9.3 and older servers
    
    A pointless and confusing error message is shown to the user when
    attempting to identify a 9.3 or older remote server with a 9.5/9.6
    pg_receivexlog, because the return signature of IDENTIFY_SYSTEM was
    changed in 9.4.  There's no good reason for the warning message, so
    shuffle code around to keep it quiet.
    
    (pg_recvlogical is also affected by this commit, but since it obviously
    cannot work with 9.3 that doesn't actually matter much.)
    
    Backpatch to 9.5.
    
    Reported by Marco Nenciarini, who also wrote the initial patch.  Further
    tweaked by Robert Haas and Fujii Masao; reviewed by Michael Paquier and
    Craig Ringer.


 src/bin/pg_basebackup/streamutil.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/src/bin/pg_basebackup/streamutil.c b/src/bin/pg_basebackup/streamutil.c
index 2c963b67a32..99828e5879d 100644
--- a/src/bin/pg_basebackup/streamutil.c
+++ b/src/bin/pg_basebackup/streamutil.c
@@ -233,10 +233,10 @@ GetConnection(void)
 /*
  * Run IDENTIFY_SYSTEM through a given connection and give back to caller
  * some result information if requested:
- * - Start LSN position
- * - Current timeline ID
  * - System identifier
- * - Plugin name
+ * - Current timeline ID
+ * - Start LSN position
+ * - Database name (NULL in servers prior to 9.4)
  */
 bool
 RunIdentifySystem(PGconn *conn, char **sysid, TimeLineID *starttli,
@@ -294,15 +294,21 @@ RunIdentifySystem(PGconn *conn, char **sysid, TimeLineID *starttli,
 	/* Get database name, only available in 9.4 and newer versions */
 	if (db_name != NULL)
 	{
-		if (PQnfields(res) < 4)
-			fprintf(stderr,
-					_("%s: could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields\n"),
-					progname, PQntuples(res), PQnfields(res), 1, 4);
+		*db_name = NULL;
+		if (PQserverVersion(conn) >= 90400)
+		{
+			if (PQnfields(res) < 4)
+			{
+				fprintf(stderr,
+						_("%s: could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields\n"),
+						progname, PQntuples(res), PQnfields(res), 1, 4);
 
-		if (PQgetisnull(res, 0, 3))
-			*db_name = NULL;
-		else
-			*db_name = pg_strdup(PQgetvalue(res, 0, 3));
+				PQclear(res);
+				return false;
+			}
+			if (!PQgetisnull(res, 0, 3))
+				*db_name = pg_strdup(PQgetvalue(res, 0, 3));
+		}
 	}
 
 	PQclear(res);


[parent: 41abf185024c]