BUG#11766427, BUG#59539: Filter by server id in mysqlbinlog fails

Problem: mysqlbinlog --server-id may filter out Format_description_log_events.
If mysqlbinlog does not process the Format_description_log_event,
then mysqlbinlog cannot read the rest of the binary log correctly.
This can have the effect that mysqlbinlog crashes, generates an error,
or generates output that causes mysqld to crash, generate an error,
or corrupt data.
Fix: Never filter out Format_description_log_events. Also, never filter
out Rotate_log_events.


client/mysqlbinlog.cc:
  Process Format_description_log_events even when the
  server_id does not match the number given by --server-id.
mysql-test/t/mysqlbinlog.test:
  Add test case.

client/mysqlbinlog.cc

@@ -705,10 +705,18 @@ Exit_status process_event(PRINT_EVENT_INFO *print_event_info, Log_event *ev,
       */
       start_datetime= 0;
       offset= 0; // print everything and protect against cycling rec_count
+      /*
+        Skip events according to the --server-id flag.  However, don't
+        skip format_description or rotate events, because they they
+        are really "global" events that are relevant for the entire
+        binlog, even if they have a server_id.  Also, we have to read
+        the format_description event so that we can parse subsequent
+        events.
+      */
+      if (ev_type != ROTATE_EVENT &&
+          server_id && (server_id != ev->server_id))
+        goto end;
     }
-    if (server_id && (server_id != ev->server_id))
-      /* skip just this event, continue processing the log. */
-      goto end;
     if (((my_time_t)(ev->when) >= stop_datetime)
         || (pos >= stop_position_mot))
     {

mysql-test/r/mysqlbinlog.result

@@ -658,3 +658,15 @@ master-bin.000002	#	Query	#	#	CREATE DATABASE test1
 master-bin.000002	#	Query	#	#	use `test1`; CREATE TABLE t1(id int)
 master-bin.000002	#	Query	#	#	use `test1`; DROP TABLE t1
 master-bin.000002	#	Query	#	#	DROP DATABASE test1
+RESET MASTER;
+USE test;
+CREATE TABLE t1 (a INT);
+SET GLOBAL SERVER_ID = 2;
+DROP TABLE t1;
+FLUSH LOGS;
+SHOW TABLES IN test;
+Tables_in_test
+t1
+SHOW TABLES IN test;
+Tables_in_test
+SET GLOBAL SERVER_ID = 1;

mysql-test/t/mysqlbinlog.test

@@ -501,3 +501,23 @@ exec $MYSQL_BINLOG $MYSQLD_DATADIR/$master_binlog | $MYSQL test 2>&1;
 let $binlog_file= query_get_value(SHOW MASTER STATUS, File, 1);
 source include/show_binlog_events.inc;
 
+#
+# BUG#11766427 BUG#59530: Filter by server id in mysqlbinlog fails
+# This test checks that the format description log event is not
+# filtered out by the --server-id option.
+#
+RESET MASTER;
+USE test;
+CREATE TABLE t1 (a INT);
+--let $old_server_id= `SELECT @@GLOBAL.SERVER_ID`
+SET GLOBAL SERVER_ID = 2;
+DROP TABLE t1;
+--let $master_binlog= query_get_value(SHOW MASTER STATUS, File, 1)
+FLUSH LOGS;
+# The following should only create t1, not drop it.
+--exec $MYSQL_BINLOG --server-id=1 $MYSQLD_DATADIR/$master_binlog | $MYSQL
+SHOW TABLES IN test;
+# The following should only drop t1, not create it.
+--exec $MYSQL_BINLOG --server-id=2 $MYSQLD_DATADIR/$master_binlog | $MYSQL
+SHOW TABLES IN test;
+eval SET GLOBAL SERVER_ID = $old_server_id;