lock0prdt.h

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/** @file include/lock0prdt.h
 The predicate lock system
 
 Created 9/7/2013 Jimmy Yang
 *******************************************************/
#ifndef lock0prdt_h
#define lock0prdt_h
 
#include "lock0lock.h"
#include "univ.i"
 
/* Predicate lock data */
typedef struct lock_prdt {
  void *data; /* Predicate data */
  uint16 op;  /* Predicate operator */
} lock_prdt_t;
 
/** Acquires LOCK_S | LOCK_PREDICATE on a block. Always succeeds, because it
never has to wait, because their only purpose is to block conflicting
LOCK_X | LOCK_PREDICATE | LOCK_INSERT_INTENTION into the locked area.
(In other words they are conceptually similar to gap locks in regular indexes,
which also never have to wait for similar reasons)
@param[in]  block   Buffer block containing the rec
@param[in]  prdt    Predicate for the lock
@param[in]  index   Secondary index containing the block
@param[in]  thr     The query thread requesting the lock */
void lock_prdt_lock(buf_block_t *block, lock_prdt_t *prdt, dict_index_t *index,
                    que_thr_t *thr);
 
/** Acquire a "Page" lock on a block
@param[in]  page_id   id of the page to lock
@param[in]  index     secondary index
@param[in]  thr       query thread
@return DB_SUCCESS */
dberr_t lock_place_prdt_page_lock(const page_id_t &page_id, dict_index_t *index,
                                  que_thr_t *thr);
 
/** Initiate a Predicate lock from a MBR */
void lock_init_prdt_from_mbr(
    lock_prdt_t *prdt, /*!< in/out: predicate to initialized */
    rtr_mbr_t *mbr,    /*!< in: Minimum Bounding Rectangle */
    ulint mode,        /*!< in: Search mode */
    mem_heap_t *heap); /*!< in: heap for allocating memory */
 
/** Get predicate lock's minimum bounding box
 @return the minimum bounding box*/
lock_prdt_t *lock_get_prdt_from_lock(const lock_t *lock); /*!< in: the lock */
 
/** Checks if a predicate lock request for a new lock has to wait for
 request lock2.
 @return true if new lock has to wait for lock2 to be removed */
bool lock_prdt_has_to_wait(
    const trx_t *trx,     /*!< in: trx of new lock */
    ulint type_mode,      /*!< in: precise mode of the new lock
                        to set: LOCK_S or LOCK_X, possibly
                        ORed to LOCK_PREDICATE or LOCK_PRDT_PAGE,
                        LOCK_INSERT_INTENTION */
    lock_prdt_t *prdt,    /*!< in: lock predicate to check */
    const lock_t *lock2); /*!< in: another record lock; NOTE that
                          it is assumed that this has a lock bit
                          set on the same record as in the new
                          lock we are setting */
 
/** Update predicate lock when page splits
 
@param[in,out]  block       page to be split
@param[in,out]  new_block   the new half page
@param[in]      prdt        MBR on the old page
@param[in]      new_prdt    MBR on the new page
*/
void lock_prdt_update_split(buf_block_t *block, buf_block_t *new_block,
                            lock_prdt_t *prdt, lock_prdt_t *new_prdt);
 
/** Adjust locks from an ancestor page of Rtree on the appropriate level .
Check whether any predicate lock in parent needs to propagate to child page
after split.
 
@param[in,out]  left_block    page to be split
@param[in,out]  right_block   the new half page
@param[in]      left_prdt     MBR on the old page
@param[in]      right_prdt    MBR on the new page
@param[in]      page_id       the parent's page id
*/
void lock_prdt_update_parent(buf_block_t *left_block, buf_block_t *right_block,
                             lock_prdt_t *left_prdt, lock_prdt_t *right_prdt,
                             const page_id_t &page_id);
 
/** Checks if locks of other transactions prevent an immediate insert of
 a predicate record.
 @return DB_SUCCESS, DB_LOCK_WAIT, or DB_DEADLOCK */
dberr_t lock_prdt_insert_check_and_lock(
    ulint flags,         /*!< in: if BTR_NO_LOCKING_FLAG bit is
                         set, does nothing */
    const rec_t *rec,    /*!< in: record after which to insert */
    buf_block_t *block,  /*!< in/out: buffer block of rec */
    dict_index_t *index, /*!< in: index */
    que_thr_t *thr,      /*!< in: query thread */
    mtr_t *mtr,          /*!< in/out: mini-transaction */
    lock_prdt_t *prdt);  /*!< in: Minimum Bound Rectangle */
 
/** Append a predicate to the lock
@param[in] lock Lock
@param[in] prdt Predicate */
void lock_prdt_set_prdt(lock_t *lock, const lock_prdt_t *prdt);
 
#if 0
 
/*********************************************************************//**
Get predicate lock's minimum bounding box
@return the minimum bounding box*/
static inline
rtr_mbr_t*
prdt_get_mbr_from_prdt(
        const lock_prdt_t*      prdt);  /*!< in: the lock predicate */
 
#endif
/** Moves the locks of a record to another record and resets the lock bits of
 the donating record. */
void lock_prdt_rec_move(
    const buf_block_t *receiver, /*!< in: buffer block containing
                                 the receiving record */
    const buf_block_t *donator); /*!< in: buffer block containing
                                 the donating record */
 
/** Check whether there are R-tree Page locks on a page by other transactions
@param[in]      trx     trx to test the lock
@param[in]      page_id id of the page
@retval false   if there is no lock
@retval true    if some transaction other than trx holds a page lock */
bool lock_other_has_prdt_page_lock(const trx_t *trx, const page_id_t &page_id);
 
/** Removes predicate lock objects set on an index page which is discarded.
@param[in]      block           page to be discarded
@param[in]      lock_hash       lock hash */
void lock_prdt_page_free_from_discard(const buf_block_t *block,
                                      struct Locks_hashtable &lock_hash);
 
#endif