lock0iter.h File Reference

#include "univ.i"
#include "lock0types.h"

Include dependency graph for lock0iter.h:

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Data Structures
struct	lock_queue_iterator_t

Functions
UNIV_INTERN void	lock_queue_iterator_reset (lock_queue_iterator_t *iter, const lock_t *lock, ulint bit_no)
const lock_t *	lock_queue_iterator_get_prev (lock_queue_iterator_t *iter)

Detailed Description

Lock queue iterator type and function prototypes.

Created July 16, 2007 Vasil Dimov

Function Documentation

const lock_t* lock_queue_iterator_get_prev

(

lock_queue_iterator_t *

iter

)

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).

Returns

previous lock or NULL in/out: iterator

UNIV_INTERN void lock_queue_iterator_reset	(	lock_queue_iterator_t *	iter,
		const lock_t *	lock,
		ulint	bit_no
	)

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. in: record number in the heap

Parameters

iter	out: iterator
lock	in: lock to start from