Bug #31240 load data infile replication between (4.0 or 4.1) and 5.1 fails

It's a regression issue.
The reason of the bug appeared to be an error introduced into 5.1 source code.
A piece of code in Create_file_log_event::do_apply_event() did not have test
coverage which made make test and pb unaware.
      
Fixed with inverting the old value of the return value from 
Create_file_log_event::do_apply_event().
The rpl test suite is extended with `rpl_cross_version' the file to hold 
regression cases similar to the current.


mysql-test/suite/rpl/r/rpl_cross_version.result:
  new results file
mysql-test/suite/rpl/t/rpl_cross_version-master.opt:
  options to the server to be able to start replication to itself
mysql-test/suite/rpl/t/rpl_cross_version.test:
  regression test for bug#31240.
sql/log_event.cc:
  Correcting the return value from  Create_file_log_event::do_apply_event()

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

+==== Initialize ====
+Setting up fake replication from MYSQL_TEST_DIR/suite/binlog/std_data/binlog_old_version_4_1.000001
+==== Test ====
+start slave sql_thread;
+==== a prove that the /home/andrei/MySQL/BZR/FIXES/bug31240-ldi_41_2_51/mysql-test/suite/binlog/std_data/binlog_old_version_4_1.000001 has been processed successfully ====
+SELECT COUNT(*) - 17920 as zero FROM t3;
+zero
+0
+==== Clean up ====
+stop slave sql_thread;
+Cleaning up after setup_fake_relay_log.inc
+drop table t1, t3;

mysql-test/suite/rpl/t/rpl_cross_version-master.opt

+--replicate-same-server-id --relay-log=slave-relay-bin

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

+# ==== Purpose ====
+#
+# Verify cross-version replication from an old master to the up-to-date slave
+#
+# ==== Implementation ====
+#
+# Feed to the slave server a binlog recorded on an old version master 
+# via setting up slave-to-slave replication. The latter is done by means of
+# the opt file and include/setup_fake_relay_log.inc.
+# The master's binlog is treated as a relay log that the SQL thread executes.
+#
+
+--source include/have_log_bin.inc
+
+#
+# Bug#31240 load data infile replication between (4.0 or 4.1) and 5.1 fails
+#
+
+--echo ==== Initialize ====
+# the relay log contains create t1, t3 tables and load data infile
+--let $fake_relay_log = $MYSQL_TEST_DIR/suite/binlog/std_data/binlog_old_version_4_1.000001
+--source include/setup_fake_relay_log.inc
+
+--echo ==== Test ====
+start slave sql_thread;
+--let $slave_param = Exec_Master_Log_Pos
+# end_log_pos of the last event of the relay log
+--let $slave_param_value = 149436
+--source include/wait_for_slave_param.inc
+--echo ==== a prove that the $fake_relay_log has been processed successfully ====
+SELECT COUNT(*) - 17920 as zero FROM t3;
+
+--echo ==== Clean up ====
+stop slave sql_thread;
+--source include/cleanup_fake_relay_log.inc
+drop table t1, t3;

sql/log_event.cc

@@ -5945,8 +5945,15 @@ void Create_file_log_event::pack_info(Protocol *protocol)
 #endif /* defined(HAVE_REPLICATION) && !defined(MYSQL_CLIENT) */
 
 
-/*
+/**
   Create_file_log_event::do_apply_event()
+  Constructor for Create_file_log_event to intantiate an event
+  from the relay log on the slave.
+
+  @retval
+    0           Success
+  @retval
+    1           Failure
 */
 
 #if defined(HAVE_REPLICATION) && !defined(MYSQL_CLIENT)
@@ -6015,7 +6022,7 @@ int Create_file_log_event::do_apply_event(Relay_log_info const *rli)
   if (fd >= 0)
     my_close(fd, MYF(0));
   thd_proc_info(thd, 0);
-  return error == 0;
+  return error != 0;
 }
 #endif /* defined(HAVE_REPLICATION) && !defined(MYSQL_CLIENT) */