函数lock_rec_bitmap_reset

 

/*********************************************************************//**
Resets the record lock bitmap to zero. NOTE: does not touch the wait_lock
pointer in the transaction! This function is used in lock object creation
and resetting. */
static
void
lock_rec_bitmap_reset(
/*==================*/
    lock_t*    lock)    /*!< in: record lock */
{
    ulint    n_bytes;

    ut_ad(lock_get_type_low(lock) == LOCK_REC);

    /* Reset to zero the bitmap which resides immediately after the lock
    struct */

    n_bytes = lock_rec_get_n_bits(lock) / 8;

    ut_ad((lock_rec_get_n_bits(lock) % 8) == 0);

    memset(&lock[1], 0, n_bytes);
}