Fix for bug #28652: MySQL (with-debug=full) asserts when alter table operations

Problem: we may create a deadlock committing changes in the mysql_alter_table() when 
LOCK_open is set. Moreover, "in some variants of the ALTER TABLE commit
happens earlier, outside of LOCK_open, in other later - inside. It's no good, a storage 
engine code that is called in between could expect a consistency - either there is a 
transaction or there is not".
Fix: move the commit to happen earlier and outside of the LOCK_open.


mysql-test/r/innodb_mysql.result:
  Fix for bug #28652: MySQL (with-debug=full) asserts when alter table operations
    - test result.
mysql-test/t/innodb_mysql.test:
  Fix for bug #28652: MySQL (with-debug=full) asserts when alter table operations
    - test case.
sql/sql_table.cc:
  Fix for bug #28652: MySQL (with-debug=full) asserts when alter table operations
    - commit moved to happen earlier in the mysql_alter_table(), 
      now we commit changes at the same time as in case when a temporary 
      table is used.

1 files changed, 9 insertions, 12 deletions

diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 079cc0d6456..27d049e2d06 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -3776,6 +3776,9 @@ view_err:
                             alter_info->keys_onoff);
     table->file->external_lock(thd, F_UNLCK);
     VOID(pthread_mutex_unlock(&LOCK_open));
+    error= ha_commit_stmt(thd);
+    if (ha_commit(thd))
+      error= 1;
   }
 
   thd->last_insert_id=next_insert_id;		// Needed for correct log
@@ -3946,16 +3949,6 @@ view_err:
       goto err;
     }
   }
-  /* The ALTER TABLE is always in its own transaction */
-  error = ha_commit_stmt(thd);
-  if (ha_commit(thd))
-    error=1;
-  if (error)
-  {
-    VOID(pthread_mutex_unlock(&LOCK_open));
-    broadcast_refresh();
-    goto err;
-  }
   thd->proc_info="end";
   if (mysql_bin_log.is_open())
   {
@@ -4165,8 +4158,12 @@ copy_data_between_tables(TABLE *from,TABLE *to,
   }
   to->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY);
 
-  ha_enable_transaction(thd,TRUE);
-
+  if (ha_enable_transaction(thd, TRUE))
+  {
+    error= 1;
+    goto err;
+  }
+  
   /*
     Ensure that the new table is saved properly to disk so that we
     can do a rename