bk commit into 5.1 tree (anozdrin:1.2519) BUG#31222

[Alexander Nozdrin]

Below is the list of changes that have just been committed into a local
5.1 repository of anozdrin.  When anozdrin does a push these changes
will be propagated to the main repository and, within 24 hours after the
push, to the public repository.
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see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2008-02-06 15:13:55+03:00, anozdrin@quad. +2 -0
  Fix for Bug#31222: com_% global status counters
  behave randomly with mysql_change_user.
  
  The problem was that global status variables were not updated
  in THD::check_user(), so thread statistics were lost after
  COM_CHANGE_USER.
  
  The fix is to update global status variables with the thread ones
  before preparing the thread for new user.

  sql/sql_class.cc@stripped, 2008-02-06 15:13:54+03:00, anozdrin@quad. +4 -0
    Update global status variables when we're handling
    COM_CHANGE_USER for a thread.

  tests/mysql_client_test.c@stripped, 2008-02-06 15:13:54+03:00, anozdrin@quad. +103 -0
    Add a test case for Bug#31222: com_% global status counters
    behave randomly with mysql_change_user.

diff -Nrup a/sql/sql_class.cc b/sql/sql_class.cc
--- a/sql/sql_class.cc	2008-01-23 01:45:42 +03:00
+++ b/sql/sql_class.cc	2008-02-06 15:13:54 +03:00
@@ -769,6 +769,10 @@ void THD::init_for_queries()
 
 void THD::change_user(void)
 {
+  pthread_mutex_lock(&LOCK_status);
+  add_to_status(&global_status_var, &status_var);
+  pthread_mutex_unlock(&LOCK_status);
+
   cleanup();
   killed= NOT_KILLED;
   cleanup_done= 0;
diff -Nrup a/tests/mysql_client_test.c b/tests/mysql_client_test.c
--- a/tests/mysql_client_test.c	2008-01-11 04:04:30 +03:00
+++ b/tests/mysql_client_test.c	2008-02-06 15:13:54 +03:00
@@ -17232,6 +17232,108 @@ static void test_bug31669()
 }
 
 /*
+  Bug#31222: com_% global status counters behave randomly with
+  mysql_change_user.
+*/
+
+static void test_bug31222()
+{
+  MYSQL con;
+  MYSQL_RES *rs;
+  MYSQL_ROW row;
+
+  int i;
+  int com_select_1;
+  int com_select_2;
+
+  /***********************************************************************
+   Prepare: create a new connection, flush statistics.
+  ***********************************************************************/
+
+  DIE_UNLESS(mysql_init(&con));
+
+  DIE_UNLESS(mysql_real_connect(&con,
+                                opt_host,
+                                opt_user,
+                                opt_password,
+                                opt_db ? opt_db : "test",
+                                opt_port,
+                                opt_unix_socket,
+                                CLIENT_FOUND_ROWS));
+
+  DIE_IF(mysql_query(&con, "FLUSH STATUS"));
+
+  /***********************************************************************
+   Do 100 SELECTs.
+  ***********************************************************************/
+
+  for (i= 0; i < 100; ++i)
+  {
+    DIE_IF(mysql_query(&con, "SELECT now()"));
+    DIE_UNLESS(rs= mysql_store_result(&con));
+
+    while (1)
+    {
+      MYSQL_ROW row= mysql_fetch_row(rs);
+
+      if (!row)
+        break;
+    }
+
+    mysql_free_result(rs);
+  }
+
+  /***********************************************************************
+   SHOW GLOBAL STATUS.
+  ***********************************************************************/
+
+  DIE_IF(mysql_query(&con, "SHOW GLOBAL STATUS LIKE 'com_select'"));
+  DIE_UNLESS(rs= mysql_store_result(&con));
+  DIE_UNLESS(row= mysql_fetch_row(rs));
+
+  DIE_UNLESS(row[1]);
+
+  com_select_1= atoi(row[1]);
+
+  mysql_free_result(rs);
+
+  /***********************************************************************
+   mysql_change_user().
+  ***********************************************************************/
+
+  DIE_IF(mysql_change_user(&con,
+                           opt_user,
+                           opt_password,
+                           opt_db ? opt_db : "test"));
+
+  /***********************************************************************
+   SHOW GLOBAL STATUS.
+  ***********************************************************************/
+
+  DIE_IF(mysql_query(&con, "SHOW GLOBAL STATUS LIKE 'com_select'"));
+  DIE_UNLESS(rs= mysql_store_result(&con));
+  DIE_UNLESS(row= mysql_fetch_row(rs));
+
+  DIE_UNLESS(row[1]);
+
+  com_select_2= atoi(row[1]);
+
+  mysql_free_result(rs);
+
+  /***********************************************************************
+   Check.
+  ***********************************************************************/
+
+  DIE_UNLESS(com_select_1 == com_select_2);
+
+  /***********************************************************************
+   That's it. Cleanup.
+  ***********************************************************************/
+
+  mysql_close(&con);
+}
+
+/*
   Read and parse arguments and MySQL options from my.cnf
 */
 
@@ -17535,6 +17637,7 @@ static struct my_tests_st my_tests[]= {
   { "test_bug20023", test_bug20023 },
   { "test_bug31418", test_bug31418 },
   { "test_bug31669", test_bug31669 },
+  { "test_bug31222", test_bug31222 },
   { 0, 0 }
 };