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Diffstat (limited to 'storage/innobase/include/lock0iter.h')
-rw-r--r-- | storage/innobase/include/lock0iter.h | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/storage/innobase/include/lock0iter.h b/storage/innobase/include/lock0iter.h new file mode 100644 index 00000000000..d063a360c1f --- /dev/null +++ b/storage/innobase/include/lock0iter.h @@ -0,0 +1,52 @@ +/****************************************************** +Lock queue iterator type and function prototypes. + +(c) 2007 Innobase Oy + +Created July 16, 2007 Vasil Dimov +*******************************************************/ + +#ifndef lock0iter_h +#define lock0iter_h + +#include "univ.i" +#include "lock0types.h" + +typedef struct lock_queue_iterator_struct { + 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. */ + +void +lock_queue_iterator_reset( +/*======================*/ + lock_queue_iterator_t* iter, /* out: iterator */ + 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). */ + +lock_t* +lock_queue_iterator_get_prev( +/*=========================*/ + /* out: previous lock or NULL */ + lock_queue_iterator_t* iter); /* in/out: iterator */ + +#endif /* lock0iter_h */ |