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/** @file include/ut0wqueue.h
 A work queue

 Created 4/26/2006 Osku Salerma
 ************************************************************************/

/** A Work queue. Threads can add work items to the queue and other threads can
 wait for work items to be available and take them off the queue for
 processing.
 ************************************************************************/

#ifndef IB_WORK_QUEUE_H
#define IB_WORK_QUEUE_H

#include "mem0mem.h"
#include "sync0sync.h"
#include "ut0list.h"

// Forward declaration
struct ib_list_t;
struct ib_wqueue_t;

/** Create a new work queue.
 @return work queue */
ib_wqueue_t *ib_wqueue_create();

/** Free a work queue. */
void ib_wqueue_free(ib_wqueue_t *wq); /*!< in: work queue */

/** Add a work item to the queue. */
void ib_wqueue_add(ib_wqueue_t *wq,   /*!< in: work queue */
                   void *item,        /*!< in: work item */
                   mem_heap_t *heap); /*!< in: memory heap to use for
                                      allocating the list node */

/********************************************************************
Check if queue is empty. */
ibool ib_wqueue_is_empty(
    /* out: TRUE if queue empty
    else FALSE */
    const ib_wqueue_t *wq); /* in: work queue */

/********************************************************************
Wait for a work item to appear in the queue for specified time. */
void *ib_wqueue_timedwait(
    /* out: work item or NULL on timeout*/
    ib_wqueue_t *wq,          /* in: work queue */
    ib_time_t wait_in_usecs); /* in: wait time in micro seconds */

#endif /* IB_WORK_QUEUE_H */