Merge lp:~vlad-lesin/percona-server/5.1-bug915814 into lp:percona-server/5.1

[Vlad Lesin]

This is backport of fix for bug #915814 from
  https://code.launchpad.net/~akopytov/percona-server/bug915814-5.5 revision 228.

  Revision 443 of this branch already contains fixes for this bug but not all of them. The
  differences between them are the following:
  1) 5.5 fix uses macros for counting buffer size for query in replication slave
  event handler while 5.1 fix does not;
  2) QueryStripComments::set() - copy the next symbol from query string to buffer
  only if it's index does not exceed query length;
  3) QueryStripComments_Backup::QueryStripComments_Backup() - copy current DB name
  length(thd->db_length) to the end of QueryStripComments::query() buffer after
  terminating NULL;
  4) Query_cache::send_result_to_client() - the same as 3;
  5) percona_bug856404 test case.

  All items except 1 are backported.

http://jenkins.percona.com/view/PS%205.1/job/percona-server-5.1-param/592

[Laurynas Biveinis (laurynas-biveinis)]

review: Approve

[Vlad Lesin (vlad-lesin)]

Rebased on GCA: http://jenkins.percona.com/view/PS%205.1/job/percona-server-5.1-param/601.

[Vlad Lesin (vlad-lesin)]

The null merges to 5.5 and 5.6 are here: lp:~vlad-lesin/percona-server/5.5-bug915814 , lp:~vlad-lesin/percona-server/5.6-bug915814 .

=== added file 'Percona-Server/mysql-test/r/percona_bug856404.result'
--- Percona-Server/mysql-test/r/percona_bug856404.result	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/r/percona_bug856404.result	2014-03-03 08:12:47 +0000
@@ -0,0 +1,8 @@
+DROP TABLE IF EXISTS table17_int;
+DROP TABLE IF EXISTS table30_int;
+CREATE TABLE `table17_int` (pk integer auto_increment primary key, `col_char_10_not_null_key` char(10), `col_enum_not_null_key` int);
+CREATE TABLE `table30_int` (pk integer auto_increment primary key, `col_enum_not_null_key` int);
+SELECT X . `pk` FROM `table17_int` AS X LEFT JOIN `table30_int` AS Y USING ( `col_enum_not_null_key` ) WHERE X . `col_char_10_not_null_key` != '   you need to translate Views labels into other languages, consider installing the <a href=\" !path\">Internationalization</a> package\'s Views translation module.' LIMIT 7  /*Generated by THREAD_ID 1*/;
+pk
+DROP TABLE table17_int;
+DROP TABLE table30_int;

=== added file 'Percona-Server/mysql-test/t/percona_bug856404-master.opt'
--- Percona-Server/mysql-test/t/percona_bug856404-master.opt	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/t/percona_bug856404-master.opt	2014-03-03 08:12:47 +0000
@@ -0,0 +1,1 @@
+--query-cache-size=10M --query-cache-strip-comments

=== added file 'Percona-Server/mysql-test/t/percona_bug856404.test'
--- Percona-Server/mysql-test/t/percona_bug856404.test	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/t/percona_bug856404.test	2014-03-03 08:12:47 +0000
@@ -0,0 +1,15 @@
+########################################################################
+# Bug #856404: Crash when query_cache_strip_comments enabled
+########################################################################
+
+--disable_warnings
+DROP TABLE IF EXISTS table17_int;
+DROP TABLE IF EXISTS table30_int;
+--enable_warnings
+
+CREATE TABLE `table17_int` (pk integer auto_increment primary key, `col_char_10_not_null_key` char(10), `col_enum_not_null_key` int);
+CREATE TABLE `table30_int` (pk integer auto_increment primary key, `col_enum_not_null_key` int);
+SELECT X . `pk` FROM `table17_int` AS X LEFT JOIN `table30_int` AS Y USING ( `col_enum_not_null_key` ) WHERE X . `col_char_10_not_null_key` != '   you need to translate Views labels into other languages, consider installing the <a href=\" !path\">Internationalization</a> package\'s Views translation module.' LIMIT 7  /*Generated by THREAD_ID 1*/;
+
+DROP TABLE table17_int;
+DROP TABLE table30_int;

=== modified file 'Percona-Server/sql/sql_cache.cc'
--- Percona-Server/sql/sql_cache.cc	2013-06-03 03:53:55 +0000
+++ Percona-Server/sql/sql_cache.cc	2014-03-03 08:12:47 +0000
@@ -466,7 +466,7 @@
         buffer[position++] = ' ';
       }
     }
-    else
+    else if (query_position < query_length)
     {
       buffer[position++] = query[query_position++];
     }
@@ -496,6 +496,7 @@
     query = thd->query();
     length = thd->query_length();
     qsc->set(query,length,thd->db_length + sizeof(size_t) + 1 + QUERY_CACHE_FLAGS_SIZE);
+    *(size_t *) (qsc->query() + qsc->query_length() + 1)= thd->db_length;
     thd->set_query(qsc->query(),qsc->query_length());
   }
   else
@@ -1788,6 +1789,7 @@
 			      thd->db_length + QUERY_CACHE_FLAGS_SIZE);
     sql          = query_strip_comments->query();
     query_length = query_strip_comments->query_length();
+    *(size_t *) (sql + query_length + 1)= thd->db_length;
   }
 
   tot_length= query_length + 1 + sizeof(size_t) +