diff options
Diffstat (limited to 'sql/lock.cc')
-rw-r--r-- | sql/lock.cc | 104 |
1 files changed, 0 insertions, 104 deletions
diff --git a/sql/lock.cc b/sql/lock.cc index 52d97a2422b..de0f39018f7 100644 --- a/sql/lock.cc +++ b/sql/lock.cc @@ -627,110 +627,6 @@ MYSQL_LOCK *mysql_lock_merge(MYSQL_LOCK *a,MYSQL_LOCK *b) } -/** - Find duplicate lock in tables. - - Temporary tables are ignored here like they are ignored in - get_lock_data(). If we allow two opens on temporary tables later, - both functions should be checked. - - @param thd The current thread. - @param needle The table to check for duplicate lock. - @param haystack The list of tables to search for the dup lock. - - @note - This is mainly meant for MERGE tables in INSERT ... SELECT - situations. The 'real', underlying tables can be found only after - the MERGE tables are opened. This function assumes that the tables are - already locked. - - @retval - NULL No duplicate lock found. - @retval - !NULL First table from 'haystack' that matches a lock on 'needle'. -*/ - -TABLE_LIST *mysql_lock_have_duplicate(THD *thd, TABLE_LIST *needle, - TABLE_LIST *haystack) -{ - MYSQL_LOCK *mylock; - TABLE **lock_tables; - TABLE *table; - TABLE *table2; - THR_LOCK_DATA **lock_locks; - THR_LOCK_DATA **table_lock_data; - THR_LOCK_DATA **end_data; - THR_LOCK_DATA **lock_data2; - THR_LOCK_DATA **end_data2; - DBUG_ENTER("mysql_lock_have_duplicate"); - - /* - Table may not be defined for derived or view tables. - Table may not be part of a lock for delayed operations. - */ - if (! (table= needle->table) || ! table->lock_count) - goto end; - - /* A temporary table does not have locks. */ - if (table->s->tmp_table == NON_TRANSACTIONAL_TMP_TABLE) - goto end; - - /* Get command lock or LOCK TABLES lock. Maybe empty for INSERT DELAYED. */ - if (! (mylock= thd->lock)) - goto end; - - /* If we have less than two tables, we cannot have duplicates. */ - if (mylock->table_count < 2) - goto end; - - lock_locks= mylock->locks; - lock_tables= mylock->table; - - /* Prepare table related variables that don't change in loop. */ - DBUG_ASSERT((table->lock_position < mylock->table_count) && - (table == lock_tables[table->lock_position])); - table_lock_data= lock_locks + table->lock_data_start; - end_data= table_lock_data + table->lock_count; - - for (; haystack; haystack= haystack->next_global) - { - if (haystack->placeholder()) - continue; - table2= haystack->table; - if (table2->s->tmp_table == NON_TRANSACTIONAL_TMP_TABLE) - continue; - - /* All tables in list must be in lock. */ - DBUG_ASSERT((table2->lock_position < mylock->table_count) && - (table2 == lock_tables[table2->lock_position])); - - for (lock_data2= lock_locks + table2->lock_data_start, - end_data2= lock_data2 + table2->lock_count; - lock_data2 < end_data2; - lock_data2++) - { - THR_LOCK_DATA **lock_data; - THR_LOCK *lock2= (*lock_data2)->lock; - - for (lock_data= table_lock_data; - lock_data < end_data; - lock_data++) - { - if ((*lock_data)->lock == lock2) - { - DBUG_PRINT("info", ("haystack match: '%s'", haystack->table_name)); - DBUG_RETURN(haystack); - } - } - } - } - - end: - DBUG_PRINT("info", ("no duplicate found")); - DBUG_RETURN(NULL); -} - - /** Unlock a set of external. */ static int unlock_external(THD *thd, TABLE **table,uint count) |