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Diffstat (limited to 'storage/innodb_plugin/include/lock0iter.h')
-rw-r--r-- | storage/innodb_plugin/include/lock0iter.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/storage/innodb_plugin/include/lock0iter.h b/storage/innodb_plugin/include/lock0iter.h new file mode 100644 index 00000000000..25a57c9740c --- /dev/null +++ b/storage/innodb_plugin/include/lock0iter.h @@ -0,0 +1,69 @@ +/***************************************************************************** + +Copyright (c) 2007, 2009, Innobase Oy. All Rights Reserved. + +This program is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free Software +Foundation; version 2 of the License. + +This program is distributed in the hope that it will be useful, but WITHOUT +ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along with +this program; if not, write to the Free Software Foundation, Inc., 59 Temple +Place, Suite 330, Boston, MA 02111-1307 USA + +*****************************************************************************/ + +/**************************************************//** +@file include/lock0iter.h +Lock queue iterator type and function prototypes. + +Created July 16, 2007 Vasil Dimov +*******************************************************/ + +#ifndef lock0iter_h +#define lock0iter_h + +#include "univ.i" +#include "lock0types.h" + +typedef struct lock_queue_iterator_struct { + const lock_t* current_lock; + /* In case this is a record lock queue (not table lock queue) + then bit_no is the record number within the heap in which the + record is stored. */ + ulint bit_no; +} lock_queue_iterator_t; + +/*******************************************************************//** +Initialize lock queue iterator so that it starts to iterate from +"lock". bit_no specifies the record number within the heap where the +record is stored. It can be undefined (ULINT_UNDEFINED) in two cases: +1. If the lock is a table lock, thus we have a table lock queue; +2. If the lock is a record lock and it is a wait lock. In this case + bit_no is calculated in this function by using + lock_rec_find_set_bit(). There is exactly one bit set in the bitmap + of a wait lock. */ +UNIV_INTERN +void +lock_queue_iterator_reset( +/*======================*/ + lock_queue_iterator_t* iter, /*!< out: iterator */ + const lock_t* lock, /*!< in: lock to start from */ + ulint bit_no);/*!< in: record number in the + heap */ + +/*******************************************************************//** +Gets the previous lock in the lock queue, returns NULL if there are no +more locks (i.e. the current lock is the first one). The iterator is +receded (if not-NULL is returned). +@return previous lock or NULL */ + +const lock_t* +lock_queue_iterator_get_prev( +/*=========================*/ + lock_queue_iterator_t* iter); /*!< in/out: iterator */ + +#endif /* lock0iter_h */ |