/*---------------------------------------------------------------------------*
  Project:  Horizon
  File:     nlib_queue.h

  Copyright (C)2009 Nintendo Co., Ltd.  All rights reserved.

  These coded instructions, statements, and computer programs contain
  proprietary information of Nintendo of America Inc. and/or Nintendo
  Company Ltd., and are protected by Federal copyright law.  They may
  not be disclosed to third parties or copied or duplicated in any form,
  in whole or in part, without the prior written consent of Nintendo.

  $Rev: 14703 $
 *---------------------------------------------------------------------------*/

/**
 * 汎用キューのマクロ定義
 */

#ifndef __NLIB_QUEUE_H__
#define __NLIB_QUEUE_H__

#ifdef __cplusplus
extern "C" {
#endif

typedef struct NLIBQueue  NLIBQueue, NLIBLink;

/**
 * NLIBキューエントリ構造体
 */
struct NLIBQueue {
    struct NLIBQueue *next;   /**< next (or head) item */
    struct NLIBQueue *prev;   /**< previous (or tail) item */
};

/**
 * Init - make queue empty
 */
#define NLIB_Queue_Init(queue)          ((queue)->next = (queue)->prev = NULL)

/**
 * QueryFirst - returns first item in the queue
 */
#define NLIB_Queue_QueryHead(queue)     ((queue)->next)

/**
 * QueryLast - returns last item in the queue
 */
#define NLIB_Queue_QueryTail(queue)     ((queue)->prev)

/**
 * QueryLinkPrev- returns previous item in the queue
 */
#define NLIB_Queue_QueryLinkPrev(item, link) ((item)->link.prev)

/**
 * QueryLinkNext- returns next item in the queue
 */
#define NLIB_Queue_QueryLinkNext(item, link) ((item)->link.next)

/**
 * IsEmtpty - tests whether a queue is empty
 */
#define NLIB_Queue_IsEmpty(queue)       ((queue)->next == NULL)

/**
 * IsEnd - tests whether the item is the end of the queue
 */
#define NLIB_Queue_IsEnd(queue, item)   ((item) == NULL)

/**
 * EnqueueAfter - insert the item after previtem in the queue
 */
#define NLIB_Queue_EnqueueAfter(type, queue, previtem, item, link)           \
do {                                                                \
    (item)->link.prev = (NLIBQueue*) (previtem);                      \
    (item)->link.next = (previtem)->link.next;                      \
    (previtem)->link.next = (NLIBQueue*) (item);                      \
    if (NLIB_Queue_IsEnd(queue, (item)->link.next))                     \
        (queue)->prev = (NLIBQueue*) (item);                          \
    else                                                            \
        ((type) (item)->link.next)->link.prev = (NLIBQueue*) (item);  \
} while (0)

/**
 * EnqueueBefore - insert the item before afteritem in the queue
 */
#define NLIB_Queue_EnqueueBefore(type, queue, item, afteritem, link)         \
do {                                                                \
    (item)->link.prev = (afteritem)->link.prev;                     \
    (item)->link.next = (NLIBQueue*) (afteritem);                     \
    (afteritem)->link.prev = (NLIBQueue*) (item);                     \
    if (NLIB_Queue_IsEnd(queue, (item)->link.prev))                     \
        (queue)->next = (NLIBQueue*) (item);                          \
    else                                                            \
        ((type) (item)->link.prev)->link.next = (NLIBQueue*) (item);  \
} while (0)

/**
 * EnqueueTail - insert the item at the tail of the queue
 */
#define NLIB_Queue_EnqueueTail(type, queue, item, link)                      \
do {                                                                \
    register NLIBQueue* ___prev;                                      \
                                                                    \
    ___prev = (queue)->prev;                                        \
    if (NLIB_Queue_IsEnd(queue, ___prev))                               \
        (queue)->next = (NLIBQueue*) (item);                          \
    else                                                            \
        ((type) ___prev)->link.next = (NLIBQueue*) (item);            \
    (item)->link.prev = ___prev;                                    \
    (item)->link.next = NULL;                                       \
    (queue)->prev = (NLIBQueue*) item;                                \
} while (0)

/**
 * EnqueueHead - insert the item at the head of the queue
 */
#define NLIB_Queue_EnqueueHead(type, queue, item, link)                      \
do {                                                                \
    register NLIBQueue* ___next;                                      \
                                                                    \
    ___next = (queue)->next;                                        \
    if (NLIB_Queue_IsEnd(queue, ___next))                               \
        (queue)->prev = (NLIBQueue*) (item);                          \
    else                                                            \
        ((type) ___next)->link.prev = (NLIBQueue*) (item);            \
    (item)->link.next = ___next;                                    \
    (item)->link.prev = NULL;                                       \
    (queue)->next = (NLIBQueue*) item;                                \
} while (0)

/**
 * DequeueItem - remove the item form the queue
 */
#define NLIB_Queue_DequeueItem(type, queue, item, link)                      \
do {                                                                \
    register NLIBQueue* ___next;                                      \
    register NLIBQueue* ___prev;                                      \
                                                                    \
    ___next = (item)->link.next;                                    \
    ___prev = (item)->link.prev;                                    \
                                                                    \
    if (NLIB_Queue_IsEnd(queue, ___next))                               \
        (queue)->prev = ___prev;                                    \
    else                                                            \
        ((type) ___next)->link.prev = ___prev;                      \
                                                                    \
    if (NLIB_Queue_IsEnd(queue, ___prev))                               \
        (queue)->next = ___next;                                    \
    else                                                            \
        ((type) ___prev)->link.next = ___next;                      \
} while (0)

/**
 * NLIB_Queue_DequeueHead - remove and return the item at the head of the queue
 * note: item is returned by reference
 */
#define NLIB_Queue_DequeueHead(type, queue, item, link)                      \
do {                                                                \
    register NLIBQueue* ___next;                                      \
                                                                    \
    (item) = (type) NLIB_Queue_QueryHead(queue);                        \
    ___next = (item)->link.next;                                    \
                                                                    \
    if (NLIB_Queue_IsEnd(queue, ___next))                               \
        (queue)->prev = NULL;                                       \
    else                                                            \
        ((type) ___next)->link.prev = NULL;                         \
    (queue)->next = ___next;                                        \
} while (0)

/**
 * NLIB_Queue_DequeueTail - remove and return the item at the tail of the queue
 * note: item is returned by reference
 */
#define NLIB_Queue_DequeueTail(type, queue, item, link)                      \
do {                                                                \
    register NLIBQueue* ___prev;                                      \
                                                                    \
    (item) = (type) NLIB_Queue_QueryTail(queue);                        \
    ___prev = (item)->link.prev;                                    \
                                                                    \
    if (NLIB_Queue_IsEnd(queue, ___prev))                               \
        (queue)->next = NULL;                                       \
    else                                                            \
        ((type) ___prev)->link.next = NULL;                         \
    (queue)->prev = ___prev;                                        \
} while (0)

/**
 *  先頭からの繰り返し
 */
#define NLIB_Queue_IterateQueue(type, queue, item, next, link)               \
    for ((item) = (type) NLIB_Queue_QueryHead(queue),                   \
         (next) = NLIB_Queue_IsEnd(queue, item) ? NULL : (type) NLIB_Queue_QueryLinkNext(item, link);    \
         !NLIB_Queue_IsEnd(queue, item);                                 \
         (item) = (next),                                           \
         (next) = NLIB_Queue_IsEnd(queue, item) ? NULL : (type) NLIB_Queue_QueryLinkNext(item, link))

/**
 *  最後尾からの繰り返し
 */
#define NLIB_Queue_IterateQueueReverse(type, queue, item, prev, link)        \
    for ((item) = (type) NLIB_Queue_QueryTail(queue),                   \
         (prev) = NLIB_Queue_IsEnd(queue, item) ? NULL : (type) NLIB_Queue_QueryLinkPrev(item, link);    \
         !NLIB_Queue_IsEnd(queue, item);                                 \
         (item) = (prev),                                           \
         (prev) = NLIB_Queue_IsEnd(queue, item) ? NULL : (type) NLIB_Queue_QueryLinkPrev(item, link))

#ifdef __cplusplus
}
#endif

/* __NLIB_QUEUE_H__ */
#endif