BUG#51987: revoke privileges logs wrong error code

A failed REVOKE statement is logged with error=0, thus causing
the slave to stop. The slave should not stop as this was an
expected error. Given that the execution failed on the master as
well the error code should be logged so that the slave can replay
the statement, get an error and compare with the master's
execution outcome. If errors match, then slave can proceed with
replication, as the error it got, when replaying the statement,
was expected.

In this particular case, the bug surfaces because the error code
is pushed to the THD diagnostics area after writing the event to
the binary log. Therefore, it would be logged with the THD
diagnostics area clean, hence its error code would not contain 
the correct code.

We fix this by moving the error reporting ahead of the call to
the routine that writes the event to the binary log.

mysql-test/suite/rpl/r/rpl_do_grant.result

@@ -242,4 +242,18 @@ GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION
 DROP TABLE t1;
 DROP PROCEDURE p1;
 DROP USER 'user49119'@'localhost';
+stop slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+reset master;
+reset slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+start slave;
+grant all on *.* to foo@"1.2.3.4";
+revoke all privileges, grant option from "foo";
+ERROR HY000: Can't revoke all privileges for one or more of the requested users
+show binlog events from <binlog_start>;
+Log_name	Pos	Event_type	Server_id	End_log_pos	Info
+master-bin.000001	#	Query	#	#	use `test`; grant all on *.* to foo@"1.2.3.4"
+master-bin.000001	#	Query	#	#	use `test`; revoke all privileges, grant option from "foo"
+DROP USER foo@"1.2.3.4";
 "End of test"

mysql-test/suite/rpl/t/rpl_do_grant.test

@@ -316,4 +316,33 @@ DROP USER 'user49119'@'localhost';
 
 -- sync_slave_with_master
 
+#
+# Bug #51987  	revoke privileges logs wrong error code
+#
+
+-- connection master
+-- source include/master-slave-reset.inc
+-- connection master
+
+grant all on *.* to foo@"1.2.3.4";
+-- error ER_REVOKE_GRANTS
+revoke all privileges, grant option from "foo";
+
+## assertion: revoke is logged
+-- source include/show_binlog_events.inc
+
+-- sync_slave_with_master
+
+## assertion: slave replicates revoke and does not fail because master
+##            logged revoke with correct expected error code
+-- let $err= query_get_value(SHOW SLAVE STATUS, Last_SQL_Errno, 1)
+  if ($err)
+{
+    -- die UNEXPECTED ERROR AT SLAVE: $err
+}
+
+-- connection master
+DROP USER foo@"1.2.3.4";
+-- sync_slave_with_master
+
 --echo "End of test"

sql/sql_acl.cc

@@ -6117,19 +6117,19 @@ bool mysql_revoke_all(THD *thd,  List <LEX_USER> &list)
 
   VOID(pthread_mutex_unlock(&acl_cache->lock));
 
-  int binlog_error=
+  if (result)
+    my_message(ER_REVOKE_GRANTS, ER(ER_REVOKE_GRANTS), MYF(0));
+
+  result= result |
     write_bin_log(thd, FALSE, thd->query(), thd->query_length());
 
   rw_unlock(&LOCK_grant);
   close_thread_tables(thd);
 
-  /* error for writing binary log has already been reported */
-  if (result && !binlog_error)
-    my_message(ER_REVOKE_GRANTS, ER(ER_REVOKE_GRANTS), MYF(0));
   /* Restore the state of binlog format */
   thd->current_stmt_binlog_row_based= save_binlog_row_based;
 
-  DBUG_RETURN(result || binlog_error);
+  DBUG_RETURN(result);
 }