MDEV-41264: binlog-in-engine dump thread not stopping at server shutdown

The binlog-in-engine code for binlog dump thread didn't check
should_stop(info, true) to stop on KILL_SERVER when it reaches the end of
the current binlog. This caused the dump threads to hang indefinitely during
SHUTDOWN WAIT FOR ALL SLAVES, and thus the shutdown to hang as well.

Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

mysql-test/suite/binlog_in_engine/rpl_master_stop.result

@@ -0,0 +1,13 @@
+include/master-slave.inc
+[connection master]
+### MDEV-41264: binlog-in-engine dump thread not stopping at server shutdown
+CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+SHUTDOWN WAIT FOR ALL SLAVES;
+include/rpl_reconnect.inc
+connection master;
+INSERT INTO t1 VALUES (2);
+connection slave;
+connection master;
+DROP TABLE t1;
+include/rpl_end.inc

mysql-test/suite/binlog_in_engine/rpl_master_stop.test

@@ -0,0 +1,31 @@
+--source include/have_binlog_format_mixed.inc
+--source include/master-slave.inc
+--source include/have_innodb_binlog.inc
+
+--echo ### MDEV-41264: binlog-in-engine dump thread not stopping at server shutdown
+
+CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+
+--write_file $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
+wait-rpl_master_stop.test
+EOF
+
+# The bug was that this shutdown would hang.
+SHUTDOWN WAIT FOR ALL SLAVES;
+--source include/wait_until_disconnected.inc
+
+--append_file $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
+restart
+EOF
+--let $rpl_server_number= 1
+--source include/rpl_reconnect.inc
+
+--connection master
+INSERT INTO t1 VALUES (2);
+--sync_slave_with_master
+
+# Cleanup.
+--connection master
+DROP TABLE t1;
+--source include/rpl_end.inc

mysql-test/suite/binlog_in_engine/rpl_shutdown_wait_slaves.cnf

@@ -0,0 +1,24 @@
+!include my.cnf
+
+[mysqld.1]
+log_warnings=3
+[mysqld.2]
+
+[mysqld.3]
+innodb
+binlog-storage-engine=innodb
+max_binlog_size=8M
+innodb-binlog-state-interval=128k
+
+[mysqld.4]
+innodb
+binlog-storage-engine=innodb
+max_binlog_size=8M
+innodb-binlog-state-interval=128k
+
+[ENV]
+SERVER_MYPORT_3=		@mysqld.3.port
+SERVER_MYSOCK_3=		@mysqld.3.socket
+
+SERVER_MYPORT_4=		@mysqld.4.port
+SERVER_MYSOCK_4=		@mysqld.4.socket

mysql-test/suite/binlog_in_engine/rpl_shutdown_wait_slaves.result

@@ -0,0 +1,29 @@
+include/rpl_init.inc [topology=1->2, 1->3, 1->4]
+connection server_1;
+CREATE TABLE t1 (a INT) ENGINE=innodb;
+connection server_2;
+connection server_3;
+connection server_4;
+include/stop_slave.inc
+connection server_1;
+connection server_1;
+SET @@GLOBAL.debug_dbug="+d,simulate_delay_at_shutdown";
+connection server_4;
+include/start_slave.inc
+connection server_1;
+SHUTDOWN WAIT FOR ALL SLAVES;
+connection server_4;
+connection server_3;
+connection server_2;
+connection server_1;
+connection default;
+connection server_1;
+connection server_1;
+DROP TABLE t1;
+connection server_2;
+include/start_slave.inc
+connection server_3;
+include/start_slave.inc
+connection server_4;
+include/start_slave.inc
+include/rpl_end.inc

mysql-test/suite/binlog_in_engine/rpl_shutdown_wait_slaves.test

@@ -0,0 +1,9 @@
+--source include/have_debug.inc
+--source include/have_binlog_format_mixed.inc
+--let $rpl_topology=1->2, 1->3, 1->4
+--source include/rpl_init.inc
+--source include/have_innodb_binlog.inc
+
+--source suite/rpl/include/rpl_shutdown_wait_slaves.inc
+
+--source include/rpl_end.inc

sql/sql_repl.cc

@@ -3592,7 +3592,8 @@ static int send_engine_events(binlog_send_info *info, LOG_INFO* linfo)
         return 1;
       }
 
-      while (!should_stop(info, true) && !reader->data_available())
+      bool stop;
+      while (!(stop= should_stop(info, true)) && !reader->data_available())
       {
         struct timespec ts;
         struct timespec *ts_ptr= nullptr;
@@ -3613,6 +3614,14 @@ static int send_engine_events(binlog_send_info *info, LOG_INFO* linfo)
           info->heartbeat_period= get_heartbeat_period(info->thd);
         }
       }
+      /*
+        Stop the dump thread during SHUTDOWN WAIT FOR ALL SLAVES (as indicated
+        by stop= should_stop(info, true)) only when we're at EOF and have no
+        more data available in the binlog.
+      */
+      if (unlikely(stop) && !reader->data_available())
+        return 1;
+
       continue;
     }