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by brian
clean slate |
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/******************************************************
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Lock queue iterator type and function prototypes.
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(c) 2007 Innobase Oy
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Created July 16, 2007 Vasil Dimov
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*******************************************************/
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#ifndef lock0iter_h
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#define lock0iter_h
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#include "univ.i" |
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#include "lock0types.h" |
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typedef struct lock_queue_iterator_struct { |
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lock_t* current_lock; |
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/* In case this is a record lock queue (not table lock queue)
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then bit_no is the record number within the heap in which the
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record is stored. */
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ulint bit_no; |
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} lock_queue_iterator_t; |
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/***********************************************************************
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Initialize lock queue iterator so that it starts to iterate from
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"lock". bit_no specifies the record number within the heap where the
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record is stored. It can be undefined (ULINT_UNDEFINED) in two cases:
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1. If the lock is a table lock, thus we have a table lock queue;
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2. If the lock is a record lock and it is a wait lock. In this case
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bit_no is calculated in this function by using
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lock_rec_find_set_bit(). There is exactly one bit set in the bitmap
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of a wait lock. */
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void
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lock_queue_iterator_reset( |
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/*======================*/
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lock_queue_iterator_t* iter, /* out: iterator */ |
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lock_t* lock, /* in: lock to start from */ |
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ulint bit_no);/* in: record number in the |
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heap */
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/***********************************************************************
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Gets the previous lock in the lock queue, returns NULL if there are no
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more locks (i.e. the current lock is the first one). The iterator is
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receded (if not-NULL is returned). */
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lock_t* |
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lock_queue_iterator_get_prev( |
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/*=========================*/
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/* out: previous lock or NULL */
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lock_queue_iterator_t* iter); /* in/out: iterator */ |
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#endif /* lock0iter_h */ |