Many files:

  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE


sql/ha_innodb.cc:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/row/row0mysql.c:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/row/row0sel.c:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/include/trx0trx.ic:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/include/row0mysql.h:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/include/trx0trx.h:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/lock/lock0lock.c:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE
innobase/trx/trx0trx.c:
  Fix Bug #3300 : if innodb_locks_unsafe_for_binlog is set, release locks on rows that we do not UPDATE or DELETE

3 files changed, 103 insertions, 6 deletions

diff --git a/innobase/include/row0mysql.h b/innobase/include/row0mysql.h
index 4bb9fa63cd1..4e6ff73b0f8 100644
--- a/innobase/include/row0mysql.h
+++ b/innobase/include/row0mysql.h
@@ -243,17 +243,27 @@ row_update_for_mysql(
 					the MySQL format */
 	row_prebuilt_t*	prebuilt);	/* in: prebuilt struct in MySQL
 					handle */
-
 /*************************************************************************
-Does an unlock of a row for MySQL. */
+This can only be used when srv_locks_unsafe_for_binlog is TRUE. Before
+calling this function we must use trx_reset_new_rec_lock_info() and
+trx_register_new_rec_lock() to store the information which new record locks
+really were set. This function removes a newly set lock under prebuilt->pcur,
+and also under prebuilt->clust_pcur. Currently, this is only used and tested
+in the case of an UPDATE or a DELETE statement, where the row lock is of the
+LOCK_X type.
+Thus, this implements a 'mini-rollback' that releases the latest record
+locks we set. */
 
 int
 row_unlock_for_mysql(
 /*=================*/
 					/* out: error code or DB_SUCCESS */
-	row_prebuilt_t*	prebuilt);	/* in: prebuilt struct in MySQL
+	row_prebuilt_t*	prebuilt,	/* in: prebuilt struct in MySQL
 					handle */
-
+	ibool		has_latches_on_recs);/* TRUE if called so that we have
+					the latches on the records under pcur
+					and clust_pcur, and we do not need to
+					reposition the cursors. */
 /*************************************************************************
 Creates an query graph node of 'update' type to be used in the MySQL
 interface. */
diff --git a/innobase/include/trx0trx.h b/innobase/include/trx0trx.h
index 8df50d6703d..1b118a86467 100644
--- a/innobase/include/trx0trx.h
+++ b/innobase/include/trx0trx.h
@@ -16,10 +16,39 @@ Created 3/26/1996 Heikki Tuuri
 #include "que0types.h"
 #include "mem0mem.h"
 #include "read0types.h"
+#include "dict0types.h"
 #include "trx0xa.h"
 
 extern ulint	trx_n_mysql_transactions;
 
+/*****************************************************************
+Resets the new record lock info in a transaction struct. */
+UNIV_INLINE
+void
+trx_reset_new_rec_lock_info(
+/*========================*/
+	trx_t*	trx);	/* in: transaction struct */
+/*****************************************************************
+Registers that we have set a new record lock on an index. This can only be
+called twice after calling trx_reset_new_rec_lock_info(), since we only have
+space to store 2 indexes! */
+UNIV_INLINE
+void
+trx_register_new_rec_lock(
+/*======================*/
+	trx_t*		trx,	/* in: transaction struct */
+	dict_index_t*	index);	/* in: trx sets a new record lock on this
+				index*/
+/*****************************************************************
+Checks if trx has set a new record lock on an index. */
+UNIV_INLINE
+ibool
+trx_new_rec_locks_contain(
+/*======================*/
+				/* out: TRUE if trx has set a new record lock
+				on index */
+	trx_t*		trx,	/* in: transaction struct */
+	dict_index_t*	index);	/* in: index */
 /************************************************************************
 Releases the search latch if trx has reserved it. */
 
@@ -495,8 +524,18 @@ struct trx_struct{
 	lock_t*		auto_inc_lock;	/* possible auto-inc lock reserved by
 					the transaction; note that it is also
 					in the lock list trx_locks */
-	ibool		trx_create_lock;/* this is TRUE if we have created a
-					new lock for a record accessed */
+	dict_index_t*	new_rec_locks[2];/* these are normally NULL; if
+					srv_locks_unsafe_for_binlog is TRUE,
+					in a cursor search, if we set a new
+					record lock on an index, this is set
+					to point to the index; this is
+					used in releasing the locks under the
+					cursors if we are performing an UPDATE
+					and we determine after retrieving
+					the row that it does not need to be
+					locked; thus, these can be used to
+					implement a 'mini-rollback' that
+					releases the latest record locks */
 	UT_LIST_NODE_T(trx_t)
 			trx_list;	/* list of transactions */
 	UT_LIST_NODE_T(trx_t)
diff --git a/innobase/include/trx0trx.ic b/innobase/include/trx0trx.ic
index 78e5acda148..d23165b74e8 100644
--- a/innobase/include/trx0trx.ic
+++ b/innobase/include/trx0trx.ic
@@ -39,4 +39,52 @@ trx_start_if_not_started_low(
 	}
 }
 
+/*****************************************************************
+Resets the new record lock info in a transaction struct. */
+UNIV_INLINE
+void
+trx_reset_new_rec_lock_info(
+/*========================*/
+	trx_t*	trx)	/* in: transaction struct */
+{
+	trx->new_rec_locks[0] = NULL;
+	trx->new_rec_locks[1] = NULL;
+}
+
+/*****************************************************************
+Registers that we have set a new record lock on an index. This can only be
+called twice after calling trx_reset_new_rec_lock_info(), since we only have
+space to store 2 indexes! */
+UNIV_INLINE
+void
+trx_register_new_rec_lock(
+/*======================*/
+	trx_t*		trx,	/* in: transaction struct */
+	dict_index_t*	index)	/* in: trx sets a new record lock on this
+				index*/
+{
+	if (trx->new_rec_locks[0] == NULL) {
+		trx->new_rec_locks[0] = index;
 
+		return;
+	}
+
+	ut_a(trx->new_rec_locks[1] == NULL);
+
+	trx->new_rec_locks[1] = index;
+}
+
+/*****************************************************************
+Checks if trx has set a new record lock on an index. */
+UNIV_INLINE
+ibool
+trx_new_rec_locks_contain(
+/*======================*/
+				/* out: TRUE if trx has set a new record lock
+				on index */
+	trx_t*		trx,	/* in: transaction struct */
+	dict_index_t*	index)	/* in: index */
+{
+	return(trx->new_rec_locks[0] == index
+	       || trx->new_rec_locks[1] == index);
+}