New file to remove sleeps in mysql-test-run (backported from 5.1)

mysql-test/include/wait_slave_status.inc

+# include/wait_slave_status.inc
+#
+# Created by Matthias Leich
+#
+# SUMMARY
+#
+#    Waits until slave has reached certain state or maximum time reached.
+#
+#    (This script will not work, when the SHOW command delivers more than one 
+#    result record, because only the first record will be caught.)
+#
+# USAGE
+#
+#    Set $result_pattern in test file and source this file:
+#
+#      let $result_pattern= <pattern used for LIKE on the result of
+#                           SHOW STATUS SLAVE>
+#      --include wait_slave_status.inc
+#
+# EXAMPLE
+#
+#    The script rpl_until.test:
+#       ...
+#       --replace_result $MASTER_MYPORT MASTER_MYPORT
+#       --replace_column 1 # 9 # 23 # 33 #
+#       --vertical_results show slave status;
+#
+#    outputs
+#       show slave status;
+#       Slave_IO_State  #
+#       Master_Host     127.0.0.1
+#       Master_User     root
+#       Master_Port     MASTER_MYPORT
+#       Connect_Retry   1
+#       Master_Log_File master-bin.000001
+#       Read_Master_Log_Pos     776
+#       Relay_Log_File  slave-relay-bin.000004
+#       Relay_Log_Pos   #
+#       Relay_Master_Log_File   master-bin.000001
+#       Slave_IO_Running        Yes
+#       Slave_SQL_Running       No
+#       Replicate_Do_DB
+#       Replicate_Ignore_DB
+#       Replicate_Do_Table
+#       Replicate_Ignore_Table
+#       Replicate_Wild_Do_Table
+#       Replicate_Wild_Ignore_Table
+#       Last_Errno      0
+#       Last_Error
+#       Skip_Counter    0
+#       Exec_Master_Log_Pos     319
+#       Relay_Log_Space #
+#       Until_Condition Master
+#       Until_Log_File  master-bin.000001
+#       Until_Log_Pos   319
+#       Master_SSL_Allowed      No
+#       Master_SSL_CA_File
+#       Master_SSL_CA_Path
+#       Master_SSL_Cert
+#       Master_SSL_Cipher
+#       Master_SSL_Key
+#       Seconds_Behind_Master   #
+#
+# The main problem with the "show slave status;" in rpl_until is, that
+# depending on the total test engine power and the current load caused by
+# other processes, the expected slave status might be not reached though
+# it will happen in maybe some seconds.
+#
+# The typical problem with rpl_until is that Slave_IO_Running is "No"
+# instead of "Yes".
+#
+# The expected result follows the LIKE pattern:
+#
+#   let $result_pattern= '%127.0.0.1%root%1%master-bin.000001%776%slave-relay-bin.000004%master-bin.000001%Yes%No%0%0%319%Master%master-bin.000001%319%No%';
+#
+# The Slave_IO_Running value is the "Yes" just after the "master-bin.000001".
+#
+# How to get this pattern ?
+#
+#     Any lines "--replace_result ..." and "--replace_colum ..." just before
+#     the SHOW TABLE STATUS and of course the expected result itself
+#     show us columns where the content must be unified, because it is non
+#     deterministic or it depends on the current test environment.
+#
+#     Unfortunately "--replace_result ..." and "--replace_colum ..." do not
+#     affect the result of our assignment    let $my_val= `SHOW SLAVE STATUS`;
+#     Therefore such content must be covered by '%'.
+#
+#     Please be careful. A more simple pattern might be dangerous, because we
+#     might get "wrong" matches. Example: There might be several "Yes" and "No"
+#     within one result row.
+#
+###############################################################################
+
+# We do not want to print the auxiliary commands, because they are not of
+# interest and their amount will vary depending how fast we get the
+# desired state.
+--disable_query_log
+
+# The protocol should show
+# - the setting of $result_pattern   and
+# - that this file is sourced           ,
+# because this increases the chance to use the protocol as replay script.
+eval SELECT "let \$result_pattern= $result_pattern ;" AS "";
+SELECT '--source include/wait_slave_status.inc' AS "";
+
+# We accept to wait maximum 30 seconds (0.2 sec/loop).
+let $max_wait= 150;
+while ($max_wait)
+{
+    let $my_val= `SHOW SLAVE STATUS`;
+    # Now we have the first record of the SHOW result set as one fat string
+    # within the variable  $my_val.
+
+    eval SET @my_val = '$my_val';
+    # DEBUG eval SELECT @my_val AS "response to SHOW SLAVE STATUS";
+
+    eval SELECT @my_val LIKE $result_pattern INTO @success;
+    # @success is     '1' if we have a match
+    #                 '0' if we have no match
+    # DEBUG SELECT @success;
+
+    let $success= `SELECT @success`;
+    let $no_success= `SELECT @success = 0`;
+    if ($success)
+    {
+       # We reached the expected result and want to jump out of the loop
+       # without unneeded sleeps.
+       # Attention: Do not set $max_wait to 0, because "while" with negative value
+       #            does not work.
+       let $max_wait= 1;
+    }
+    if ($no_success)
+    {
+       # We did not reach the expected result and will have to sleep again
+       # or jump out of the loop, when max_wait is exhausted.
+       real_sleep 0.2;
+    }
+    dec $max_wait;
+}
+--enable_query_log
+if ($no_success)
+{
+let $message= ! Attention: Timeout in wait_slave_status.inc.
+              |       Possible reasons with decreasing probability:
+              |       - The LIKE pattern ($result_pattern) is wrong, because the
+              |         testcase was altered or the layout of the
+              |         SHOW SLAVE STATUS result set changed.
+              |       - There is a new bug within the replication.
+              |       - We met an extreme testing environment and $max_wait is
+              |         too small.;
+--source include/show_msg80.inc
+--echo DEBUG INFO START (wait_slave_status.inc):
+--echo $result_pattern
+--vertical_results
+show slave status;
+--echo DEBUG INFO END
+}