Merge lp:~stewart/percona-server/bug1017192 into lp:percona-server/5.5

[Stewart Smith]

Fix: Server crashes in add_identifier on concurrent ALTER TABLE and SHOW ENGINE INNODB STATUS

Fix and test case comes from MariaDB. Without fix, test case (just about always) crashes.

http://jenkins.percona.com/view/PS%205.5/job/percona-server-5.5-param/481/

[Stewart Smith (stewart)]

MariaDB bug: https://mariadb.atlassian.net/browse/MDEV-364

[Laurynas Biveinis (laurynas-biveinis)]

Stewart -

It needs a DBUG_SYNC testcase. Also the bug & fix needs an actual explanation. It seems that MariaDB don't have one neither.

review: Needs Fixing

[Laurynas Biveinis (laurynas-biveinis)]

Also, is 5.1 affected?

review: Needs Information

[Laurynas Biveinis (laurynas-biveinis)]

I was told that MariaDB fixed it in a different way, rev. 3491 in 5.5. (did not verify this report).

Unmerged revisions

293. By Stewart Smith on 2012-09-02

Fix bug lp:1017192 Server crashes in add_identifier on concurrent ALTER TABLE and SHOW ENGINE INNODB STATUS

Fix and test comes from MariaDB: https://mariadb.atlassian.net/browse/MDEV-364

=== added file 'Percona-Server/mysql-test/r/percona_bug1017192.result'
=== added file 'Percona-Server/mysql-test/t/percona_bug1017192.test'
--- Percona-Server/mysql-test/t/percona_bug1017192.test	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/t/percona_bug1017192.test	2012-09-02 22:32:21 +0000
@@ -0,0 +1,30 @@
+--source include/have_partition.inc
+
+--disable_result_log
+--disable_query_log
+
+CREATE TABLE IF NOT EXISTS t1 (`a` INT) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1),(2),(3),(4);
+
+--connect (con1,localhost,root,,)
+--let $run = 50
+
+while ($run)
+{
+        --connection default
+        --send ALTER TABLE t1 PARTITION BY HASH (`a`) PARTITIONS 4 
+        --connection con1
+        --let $show = 300
+        while ($show)
+        {
+                SHOW ENGINE INNODB STATUS;
+                --dec $show
+        }
+        --connection default
+        --reap
+        --dec $run
+}
+
+DROP TABLE t1;
+--enable_query_log
+--enable_result_log

=== modified file 'Percona-Server/sql/sql_table.cc'
--- Percona-Server/sql/sql_table.cc	2012-08-07 06:10:00 +0000
+++ Percona-Server/sql/sql_table.cc	2012-09-02 22:32:21 +0000
@@ -209,7 +209,7 @@
   int  part_name_len= 0;
   const char *subpart_name= NULL;
   int  subpart_name_len= 0;
-  enum enum_file_name_type {NORMAL, TEMP, RENAMED} name_type= NORMAL;
+  enum enum_file_name_type {NORMAL, TEMP, RENAMED, ALTER} name_type= NORMAL;
   const char *tmp_p;
   DBUG_ENTER("explain_filename");
   DBUG_PRINT("enter", ("from '%s'", from));
@@ -252,7 +252,7 @@
                (tmp_p[2] == 'L' || tmp_p[2] == 'l') &&
                 tmp_p[3] == '-')
       {
-        name_type= TEMP;
+        name_type= ALTER;
         tmp_p+= 4; /* sql- prefix found */
       }
       else
@@ -298,7 +298,7 @@
       subpart_name_len= strlen(subpart_name);
     else
       part_name_len= strlen(part_name);
-    if (name_type != NORMAL)
+    if (name_type == TEMP || name_type == RENAMED)
     {
       if (subpart_name)
         subpart_name_len-= 5;
@@ -342,7 +342,7 @@
       to_p= strnmov(to_p, ", ", end_p - to_p);
     if (name_type != NORMAL)
     {
-      if (name_type == TEMP)
+      if (name_type == TEMP || name_type == ALTER)
         to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_TEMPORARY_NAME),
                       end_p - to_p);
       else