A fix and a test case for Bug#10760 and complementary cleanups.

The idea of the patch
is that every cursor gets its own lock id for table level locking.
Thus cursors are protected from updates performed within the same 
connection. Additionally a list of transient (must be closed at
commit) cursors is maintained and all transient cursors are closed
when necessary. Lastly, this patch adds support for deadlock
timeouts to TLL locking when using cursors.
+ post-review fixes.

1 files changed, 24 insertions, 0 deletions

diff --git a/sql/ha_myisammrg.cc b/sql/ha_myisammrg.cc
index 5d3f379081c..8c4b4e790b1 100644
--- a/sql/ha_myisammrg.cc
+++ b/sql/ha_myisammrg.cc
@@ -32,6 +32,30 @@
 ** MyISAM MERGE tables
 *****************************************************************************/
 
+/* MyISAM MERGE handlerton */
+
+static handlerton myisammrg_hton= {
+  "MRG_MyISAM",
+  0,       /* slot */
+  0,       /* savepoint size. */
+  0,       /* close_connection */
+  0,       /* savepoint */
+  0,       /* rollback to savepoint */
+  0,       /* release savepoint */
+  0,       /* commit */
+  0,       /* rollback */
+  0,       /* prepare */
+  0,       /* recover */
+  0,       /* commit_by_xid */
+  0,       /* rollback_by_xid */
+  HTON_NO_FLAGS
+};
+
+
+ha_myisammrg::ha_myisammrg(TABLE *table_arg)
+  :handler(&myisammrg_hton, table_arg), file(0)
+{}
+
 static const char *ha_myisammrg_exts[] = {
   ".MRG",
   NullS