Revert "Fix bug in checking of IDENTIFY_SYSTEM result."

MasaoFujii · MasaoFujii · commit c4762886539b · 2014-08-19T18:30:38.000+09:00
This reverts commit 083d29c. The commit changed the code so that it causes an errors when IDENTIFY_SYSTEM returns three columns. But which prevents us from using the replication-related utilities against the server with older version. This is not what we want. For that compatibility, we allow the utilities to receive three columns as the result of IDENTIFY_SYSTEM eventhough it actually returns four columns in 9.4 or later. Pointed out by Andres Freund.
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -131,7 +131,7 @@ libpqrcv_identify_system(TimeLineID *primary_tli)
 						"the primary server: %s",
 						PQerrorMessage(streamConn))));
 	}
-	if (PQnfields(res) < 4 || PQntuples(res) != 1)
+	if (PQnfields(res) < 3 || PQntuples(res) != 1)
 	{
 		int			ntuples = PQntuples(res);
 		int			nfields = PQnfields(res);
@@ -140,7 +140,7 @@ libpqrcv_identify_system(TimeLineID *primary_tli)
 		ereport(ERROR,
 				(errmsg("invalid response from primary server"),
 				 errdetail("Could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields.",
-						   ntuples, nfields, 4, 1)));
+						   ntuples, nfields, 3, 1)));
 	}
 	primary_sysid = PQgetvalue(res, 0, 0);
 	*primary_tli = pg_atoi(PQgetvalue(res, 0, 1), 4, 0);
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
@@ -1644,11 +1644,11 @@ BaseBackup(void)
 				progname, "IDENTIFY_SYSTEM", PQerrorMessage(conn));
 		disconnect_and_exit(1);
 	}
-	if (PQntuples(res) != 1 || PQnfields(res) < 4)
+	if (PQntuples(res) != 1 || PQnfields(res) < 3)
 	{
 		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);
+				progname, PQntuples(res), PQnfields(res), 1, 3);
 		disconnect_and_exit(1);
 	}
 	sysidentifier = pg_strdup(PQgetvalue(res, 0, 0));
diff --git a/src/bin/pg_basebackup/pg_receivexlog.c b/src/bin/pg_basebackup/pg_receivexlog.c
@@ -290,11 +290,11 @@ StreamLog(void)
 				progname, "IDENTIFY_SYSTEM", PQerrorMessage(conn));
 		disconnect_and_exit(1);
 	}
-	if (PQntuples(res) != 1 || PQnfields(res) < 4)
+	if (PQntuples(res) != 1 || PQnfields(res) < 3)
 	{
 		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);
+				progname, PQntuples(res), PQnfields(res), 1, 3);
 		disconnect_and_exit(1);
 	}
 	servertli = atoi(PQgetvalue(res, 0, 1));
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
@@ -499,11 +499,11 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
 			PQclear(res);
 			return false;
 		}
-		if (PQntuples(res) != 1 || PQnfields(res) < 4)
+		if (PQntuples(res) != 1 || PQnfields(res) < 3)
 		{
 			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);
+					progname, PQntuples(res), PQnfields(res), 1, 3);
 			PQclear(res);
 			return false;
 		}

Original file line number	Diff line number	Diff line change
`@@ -131,7 +131,7 @@ libpqrcv_identify_system(TimeLineID *primary_tli)`
`131`	`131`	`"the primary server: %s",`
`132`	`132`	`PQerrorMessage(streamConn))));`
`133`	`133`	`}`
`134`		`- if (PQnfields(res) < 4 \|\| PQntuples(res) != 1)`
	`134`	`+ if (PQnfields(res) < 3 \|\| PQntuples(res) != 1)`
`135`	`135`	`{`
`136`	`136`	`int ntuples = PQntuples(res);`
`137`	`137`	`int nfields = PQnfields(res);`
`@@ -140,7 +140,7 @@ libpqrcv_identify_system(TimeLineID *primary_tli)`
`140`	`140`	`ereport(ERROR,`
`141`	`141`	`(errmsg("invalid response from primary server"),`
`142`	`142`	`errdetail("Could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields.",`
`143`		`- ntuples, nfields, 4, 1)));`
	`143`	`+ ntuples, nfields, 3, 1)));`
`144`	`144`	`}`
`145`	`145`	`primary_sysid = PQgetvalue(res, 0, 0);`
`146`	`146`	`*primary_tli = pg_atoi(PQgetvalue(res, 0, 1), 4, 0);`
Original file line number	Diff line number	Diff line change
`@@ -1644,11 +1644,11 @@ BaseBackup(void)`
`1644`	`1644`	`progname, "IDENTIFY_SYSTEM", PQerrorMessage(conn));`
`1645`	`1645`	`disconnect_and_exit(1);`
`1646`	`1646`	`}`
`1647`		`- if (PQntuples(res) != 1 \|\| PQnfields(res) < 4)`
	`1647`	`+ if (PQntuples(res) != 1 \|\| PQnfields(res) < 3)`
`1648`	`1648`	`{`
`1649`	`1649`	`fprintf(stderr,`
`1650`	`1650`	`_("%s: could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields\n"),`
`1651`		`- progname, PQntuples(res), PQnfields(res), 1, 4);`
	`1651`	`+ progname, PQntuples(res), PQnfields(res), 1, 3);`
`1652`	`1652`	`disconnect_and_exit(1);`
`1653`	`1653`	`}`
`1654`	`1654`	`sysidentifier = pg_strdup(PQgetvalue(res, 0, 0));`
Original file line number	Diff line number	Diff line change
`@@ -290,11 +290,11 @@ StreamLog(void)`
`290`	`290`	`progname, "IDENTIFY_SYSTEM", PQerrorMessage(conn));`
`291`	`291`	`disconnect_and_exit(1);`
`292`	`292`	`}`
`293`		`- if (PQntuples(res) != 1 \|\| PQnfields(res) < 4)`
	`293`	`+ if (PQntuples(res) != 1 \|\| PQnfields(res) < 3)`
`294`	`294`	`{`
`295`	`295`	`fprintf(stderr,`
`296`	`296`	`_("%s: could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields\n"),`
`297`		`- progname, PQntuples(res), PQnfields(res), 1, 4);`
	`297`	`+ progname, PQntuples(res), PQnfields(res), 1, 3);`
`298`	`298`	`disconnect_and_exit(1);`
`299`	`299`	`}`
`300`	`300`	`servertli = atoi(PQgetvalue(res, 0, 1));`
Original file line number	Diff line number	Diff line change
`@@ -499,11 +499,11 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,`
`499`	`499`	`PQclear(res);`
`500`	`500`	`return false;`
`501`	`501`	`}`
`502`		`- if (PQntuples(res) != 1 \|\| PQnfields(res) < 4)`
	`502`	`+ if (PQntuples(res) != 1 \|\| PQnfields(res) < 3)`
`503`	`503`	`{`
`504`	`504`	`fprintf(stderr,`
`505`	`505`	`_("%s: could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields\n"),`
`506`		`- progname, PQntuples(res), PQnfields(res), 1, 4);`
	`506`	`+ progname, PQntuples(res), PQnfields(res), 1, 3);`
`507`	`507`	`PQclear(res);`
`508`	`508`	`return false;`
`509`	`509`	`}`