merge with 3.23.48

BUILD/FINISH.sh:
  Auto merged
BUILD/SETUP.sh:
  Auto merged
BUILD/compile-alpha:
  Auto merged
BUILD/compile-pentium-gcov:
  Auto merged
BUILD/compile-pentium-gprof:
  Auto merged
BUILD/compile-pentium:
  Auto merged
BitKeeper/deleted/.del-my_new.cc:
  Delete: mysys/my_new.cc
Build-tools/Do-compile:
  Auto merged
acconfig.h:
  Auto merged
acinclude.m4:
  Auto merged
Docs/manual.texi:
  Auto merged
bdb/dist/configure.in:
  Auto merged
client/Makefile.am:
  Auto merged
innobase/btr/btr0cur.c:
  Auto merged
innobase/buf/buf0lru.c:
  Auto merged
innobase/dict/dict0crea.c:
  Auto merged
innobase/fil/fil0fil.c:
  Auto merged
innobase/include/srv0srv.h:
  Auto merged
innobase/rem/rem0cmp.c:
  Auto merged
innobase/srv/srv0srv.c:
  Auto merged
innobase/srv/srv0start.c:
  Auto merged
innobase/trx/trx0purge.c:
  Auto merged
myisam/myisampack.c:
  Auto merged
mysql-test/mysql-test-run.sh:
  Auto merged
mysql-test/t/join.test:
  Auto merged
mysys/Makefile.am:
  Auto merged
scripts/Makefile.am:
  Auto merged
sql/ha_innodb.h:
  Auto merged
sql/handler.cc:
  Auto merged
sql/my_lock.c:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_table.cc:
  Auto merged
support-files/my-huge.cnf.sh:
  Auto merged
support-files/my-large.cnf.sh:
  Auto merged
support-files/my-medium.cnf.sh:
  Auto merged
support-files/my-small.cnf.sh:
  Auto merged
configure.in:
  merge
innobase/row/row0mysql.c:
  merge
innobase/trx/trx0trx.c:
  merge
mysql-test/r/innodb.result:
  merge
mysql-test/r/join.result:
  merge
sql/ha_innodb.cc:
  merge
sql/slave.cc:
  merge

2 files changed, 52 insertions, 4 deletions

diff --git a/innobase/trx/trx0purge.c b/innobase/trx/trx0purge.c
index 31a0c20ad14..97362d00b4b 100644
--- a/innobase/trx/trx0purge.c
+++ b/innobase/trx/trx0purge.c
@@ -226,9 +226,9 @@ trx_purge_sys_create(void)
 						   value */
 	purge_sys->sess = sess_open(com_endpoint, (byte*)"purge_system", 13);
 
-	purge_sys->trx = (purge_sys->sess)->trx;
+	purge_sys->trx = purge_sys->sess->trx;
 
-	(purge_sys->trx)->type = TRX_PURGE;
+	purge_sys->trx->type = TRX_PURGE;
 
 	ut_a(trx_start_low(purge_sys->trx, ULINT_UNDEFINED));
 
diff --git a/innobase/trx/trx0trx.c b/innobase/trx/trx0trx.c
index 315bb7030ee..607c80edd09 100644
--- a/innobase/trx/trx0trx.c
+++ b/innobase/trx/trx0trx.c
@@ -26,9 +26,9 @@ Created 3/26/1996 Heikki Tuuri
 
 
 /* Copy of the prototype for innobase_mysql_print_thd: this
-   copy must be equal to the one in mysql/sql/ha_innobase.cc ! */
-void innobase_mysql_print_thd(void* thd);
+copy must be equal to the one in mysql/sql/ha_innobase.cc ! */
 
+void innobase_mysql_print_thd(void* thd);
 
 /* Dummy session used currently in MySQL interface */
 sess_t*		trx_dummy_sess = NULL;
@@ -64,6 +64,8 @@ trx_create(
 
 	trx = mem_alloc(sizeof(trx_t));
 
+	trx->magic_n = TRX_MAGIC_N;
+
 	trx->op_info = (char *) "";
 	
 	trx->type = TRX_USER;
@@ -158,6 +160,32 @@ trx_allocate_for_mysql(void)
 }
 
 /************************************************************************
+Creates a transaction object for background operations by the master thread. */
+
+trx_t*
+trx_allocate_for_background(void)
+/*=============================*/
+				/* out, own: transaction object */
+{
+	trx_t*	trx;
+
+	mutex_enter(&kernel_mutex);
+	
+	/* Open a dummy session */
+
+	if (!trx_dummy_sess) {
+		trx_dummy_sess = sess_open(NULL, (byte*)"Dummy sess",
+						ut_strlen("Dummy sess"));
+	}
+	
+	trx = trx_create(trx_dummy_sess);
+
+	mutex_exit(&kernel_mutex);
+	
+	return(trx);
+}
+
+/************************************************************************
 Releases the search latch if trx has reserved it. */
 
 void
@@ -181,6 +209,11 @@ trx_free(
 	trx_t*	trx)	/* in, own: trx object */
 {
 	ut_ad(mutex_own(&kernel_mutex));
+
+	ut_a(trx->magic_n == TRX_MAGIC_N);
+
+	trx->magic_n = 11112222;
+
 	ut_a(trx->conc_state == TRX_NOT_STARTED);
 	
 	mutex_free(&(trx->undo_mutex));
@@ -242,6 +275,21 @@ trx_free_for_mysql(
 	mutex_exit(&kernel_mutex);
 }
 
+/************************************************************************
+Frees a transaction object of a background operation of the master thread. */
+
+void
+trx_free_for_background(
+/*====================*/
+	trx_t*	trx)	/* in, own: trx object */
+{
+	mutex_enter(&kernel_mutex);
+	
+	trx_free(trx);
+	
+	mutex_exit(&kernel_mutex);
+}
+
 /********************************************************************
 Inserts the trx handle in the trx system trx list in the right position.
 The list is sorted on the trx id so that the biggest id is at the list