lock0lock.h

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

/******************************************************
The transaction lock system

(c) 1996 Innobase Oy

Created 5/7/1996 Heikki Tuuri
*******************************************************/

#ifndef lock0lock_h
#define lock0lock_h

#include "univ.i"
#include "trx0types.h"
#include "rem0types.h"
#include "dict0types.h"
#include "que0types.h"
#include "page0types.h"
#include "lock0types.h"
#include "read0types.h"
#include "hash0hash.h"

#ifdef UNIV_DEBUG
extern ibool	lock_print_waits;
#endif /* UNIV_DEBUG */
/* Buffer for storing information about the most recent deadlock error */
extern FILE*	lock_latest_err_file;

/*************************************************************************
Gets the size of a lock struct. */

ulint
lock_get_size(void);
/*===============*/
			/* out: size in bytes */
/*************************************************************************
Creates the lock system at database start. */

void
lock_sys_create(
/*============*/
	ulint	n_cells);	/* in: number of slots in lock hash table */
/*************************************************************************
Checks if some transaction has an implicit x-lock on a record in a secondary
index. */

trx_t*
lock_sec_rec_some_has_impl_off_kernel(
/*==================================*/
				/* out: transaction which has the x-lock, or
				NULL */
	rec_t*		rec,	/* in: user record */
	dict_index_t*	index,	/* in: secondary index */
	const ulint*	offsets);/* in: rec_get_offsets(rec, index) */
/*************************************************************************
Checks if some transaction has an implicit x-lock on a record in a clustered
index. */
UNIV_INLINE
trx_t*
lock_clust_rec_some_has_impl(
/*=========================*/
				/* out: transaction which has the x-lock, or
				NULL */
	rec_t*		rec,	/* in: user record */
	dict_index_t*	index,	/* in: clustered index */
	const ulint*	offsets);/* in: rec_get_offsets(rec, index) */
/*****************************************************************
Makes a record to inherit the locks of another record as gap type
locks, but does not reset the lock bits of the other record. Also
waiting lock requests on rec are inherited as GRANTED gap locks. */

void
lock_rec_inherit_to_gap(
/*====================*/
	rec_t*	heir,	/* in: record which inherits */
	rec_t*	rec);	/* in: record from which inherited; does NOT reset
			the locks on this record */
/*****************************************************************
Updates the lock table when we have reorganized a page. NOTE: we copy
also the locks set on the infimum of the page; the infimum may carry
locks if an update of a record is occurring on the page, and its locks
were temporarily stored on the infimum. */

void
lock_move_reorganize_page(
/*======================*/
	page_t*	page,		/* in: old index page */
	page_t*	new_page);	/* in: reorganized page */
/*****************************************************************
Moves the explicit locks on user records to another page if a record
list end is moved to another page. */

void
lock_move_rec_list_end(
/*===================*/
	page_t*	new_page,	/* in: index page to move to */
	page_t*	page,		/* in: index page */
	rec_t*	rec);		/* in: record on page: this is the
				first record moved */
/*****************************************************************
Moves the explicit locks on user records to another page if a record
list start is moved to another page. */

void
lock_move_rec_list_start(
/*=====================*/
	page_t*	new_page,	/* in: index page to move to */
	page_t*	page,		/* in: index page */
	rec_t*	rec,		/* in: record on page: this is the
				first record NOT copied */
	rec_t*	old_end);	/* in: old previous-to-last record on
				new_page before the records were copied */
/*****************************************************************
Updates the lock table when a page is split to the right. */

void
lock_update_split_right(
/*====================*/
	page_t*	right_page,	/* in: right page */
	page_t*	left_page);	/* in: left page */
/*****************************************************************
Updates the lock table when a page is merged to the right. */

void
lock_update_merge_right(
/*====================*/
	rec_t*	orig_succ,	/* in: original successor of infimum
				on the right page before merge */
	page_t*	left_page);	/* in: merged index page which will be
				discarded */
/*****************************************************************
Updates the lock table when the root page is copied to another in
btr_root_raise_and_insert. Note that we leave lock structs on the
root page, even though they do not make sense on other than leaf
pages: the reason is that in a pessimistic update the infimum record
of the root page will act as a dummy carrier of the locks of the record
to be updated. */

void
lock_update_root_raise(
/*===================*/
	page_t*	new_page,	/* in: index page to which copied */
	page_t*	root);		/* in: root page */
/*****************************************************************
Updates the lock table when a page is copied to another and the original page
is removed from the chain of leaf pages, except if page is the root! */

void
lock_update_copy_and_discard(
/*=========================*/
	page_t*	new_page,	/* in: index page to which copied */
	page_t*	page);		/* in: index page; NOT the root! */
/*****************************************************************
Updates the lock table when a page is split to the left. */

void
lock_update_split_left(
/*===================*/
	page_t*	right_page,	/* in: right page */
	page_t*	left_page);	/* in: left page */
/*****************************************************************
Updates the lock table when a page is merged to the left. */

void
lock_update_merge_left(
/*===================*/
	page_t*	left_page,	/* in: left page to which merged */
	rec_t*	orig_pred,	/* in: original predecessor of supremum
				on the left page before merge */
	page_t*	right_page);	/* in: merged index page which will be
				discarded */
/*****************************************************************
Resets the original locks on heir and replaces them with gap type locks
inherited from rec. */

void
lock_rec_reset_and_inherit_gap_locks(
/*=================================*/
	rec_t*	heir,	/* in: heir record */
	rec_t*	rec);	/* in: record */
/*****************************************************************
Updates the lock table when a page is discarded. */

void
lock_update_discard(
/*================*/
	rec_t*	heir,	/* in: record which will inherit the locks */
	page_t*	page);	/* in: index page which will be discarded */
/*****************************************************************
Updates the lock table when a new user record is inserted. */

void
lock_update_insert(
/*===============*/
	rec_t*	rec);	/* in: the inserted record */
/*****************************************************************
Updates the lock table when a record is removed. */

void
lock_update_delete(
/*===============*/
	rec_t*	rec);	/* in: the record to be removed */
/*************************************************************************
Stores on the page infimum record the explicit locks of another record.
This function is used to store the lock state of a record when it is
updated and the size of the record changes in the update. The record
is in such an update moved, perhaps to another page. The infimum record
acts as a dummy carrier record, taking care of lock releases while the
actual record is being moved. */

void
lock_rec_store_on_page_infimum(
/*===========================*/
	page_t*	page,	/* in: page containing the record */
	rec_t*	rec);	/* in: record whose lock state is stored
			on the infimum record of the same page; lock
			bits are reset on the record */
/*************************************************************************
Restores the state of explicit lock requests on a single record, where the
state was stored on the infimum of the page. */

void
lock_rec_restore_from_page_infimum(
/*===============================*/
	rec_t*	rec,	/* in: record whose lock state is restored */
	page_t*	page);	/* in: page (rec is not necessarily on this page)
			whose infimum stored the lock state; lock bits are
			reset on the infimum */ 
/*************************************************************************
Returns TRUE if there are explicit record locks on a page. */

ibool
lock_rec_expl_exist_on_page(
/*========================*/
			/* out: TRUE if there are explicit record locks on
			the page */
	ulint	space,	/* in: space id */
	ulint	page_no);/* in: page number */
/*************************************************************************
Checks if locks of other transactions prevent an immediate insert of
a record. If they do, first tests if the query thread should anyway
be suspended for some reason; if not, then puts the transaction and
the query thread to the lock wait state and inserts a waiting request
for a gap x-lock to the lock queue. */

ulint
lock_rec_insert_check_and_lock(
/*===========================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DEADLOCK, or DB_QUE_THR_SUSPENDED */
	ulint		flags,	/* in: if BTR_NO_LOCKING_FLAG bit is set,
				does nothing */
	rec_t*		rec,	/* in: record after which to insert */
	dict_index_t*	index,	/* in: index */
	que_thr_t*	thr,	/* in: query thread */
	ibool*		inherit);/* out: set to TRUE if the new inserted
				record maybe should inherit LOCK_GAP type
				locks from the successor record */
/*************************************************************************
Checks if locks of other transactions prevent an immediate modify (update,
delete mark, or delete unmark) of a clustered index record. If they do,
first tests if the query thread should anyway be suspended for some
reason; if not, then puts the transaction and the query thread to the
lock wait state and inserts a waiting request for a record x-lock to the
lock queue. */

ulint
lock_clust_rec_modify_check_and_lock(
/*=================================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DEADLOCK, or DB_QUE_THR_SUSPENDED */
	ulint		flags,	/* in: if BTR_NO_LOCKING_FLAG bit is set,
				does nothing */
	rec_t*		rec,	/* in: record which should be modified */
	dict_index_t*	index,	/* in: clustered index */
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	que_thr_t*	thr);	/* in: query thread */
/*************************************************************************
Checks if locks of other transactions prevent an immediate modify
(delete mark or delete unmark) of a secondary index record. */

ulint
lock_sec_rec_modify_check_and_lock(
/*===============================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DEADLOCK, or DB_QUE_THR_SUSPENDED */
	ulint		flags,	/* in: if BTR_NO_LOCKING_FLAG bit is set,
				does nothing */
	rec_t*		rec,	/* in: record which should be modified;
				NOTE: as this is a secondary index, we
				always have to modify the clustered index
				record first: see the comment below */
	dict_index_t*	index,	/* in: secondary index */
	que_thr_t*	thr);	/* in: query thread */
/*************************************************************************
Like the counterpart for a clustered index below, but now we read a
secondary index record. */

ulint
lock_sec_rec_read_check_and_lock(
/*=============================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DEADLOCK, or DB_QUE_THR_SUSPENDED */
	ulint		flags,	/* in: if BTR_NO_LOCKING_FLAG bit is set,
				does nothing */
	rec_t*		rec,	/* in: user record or page supremum record
				which should be read or passed over by a read
				cursor */
	dict_index_t*	index,	/* in: secondary index */
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	ulint		mode,	/* in: mode of the lock which the read cursor
				should set on records: LOCK_S or LOCK_X; the
				latter is possible in SELECT FOR UPDATE */
	ulint		gap_mode,/* in: LOCK_ORDINARY, LOCK_GAP, or
				LOCK_REC_NOT_GAP */
	que_thr_t*	thr);	/* in: query thread */
/*************************************************************************
Checks if locks of other transactions prevent an immediate read, or passing
over by a read cursor, of a clustered index record. If they do, first tests
if the query thread should anyway be suspended for some reason; if not, then
puts the transaction and the query thread to the lock wait state and inserts a
waiting request for a record lock to the lock queue. Sets the requested mode
lock on the record. */

ulint
lock_clust_rec_read_check_and_lock(
/*===============================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DEADLOCK, or DB_QUE_THR_SUSPENDED */
	ulint		flags,	/* in: if BTR_NO_LOCKING_FLAG bit is set,
				does nothing */
	rec_t*		rec,	/* in: user record or page supremum record
				which should be read or passed over by a read
				cursor */
	dict_index_t*	index,	/* in: clustered index */
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	ulint		mode,	/* in: mode of the lock which the read cursor
				should set on records: LOCK_S or LOCK_X; the
				latter is possible in SELECT FOR UPDATE */
	ulint		gap_mode,/* in: LOCK_ORDINARY, LOCK_GAP, or
				LOCK_REC_NOT_GAP */
	que_thr_t*	thr);	/* in: query thread */