88 lines
2.9 KiB
C
88 lines
2.9 KiB
C
|
/************************************************************
|
||
|
|
* sq_remlast.c
|
||
|
|
*
|
||
|
|
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
|
||
|
|
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
|
||
|
|
*
|
||
|
|
* Redistribution and use in source and binary forms, with or without
|
||
|
|
* modification, are permitted provided that the following conditions
|
||
|
|
* are met:
|
||
|
|
*
|
||
|
|
* 1. Redistributions of source code must retain the above copyright
|
||
|
|
* notice, this list of conditions and the following disclaimer.
|
||
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||
|
|
* notice, this list of conditions and the following disclaimer in
|
||
|
|
* the documentation and/or other materials provided with the
|
||
|
|
* distribution.
|
||
|
|
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
|
||
|
|
* used to endorse or promote products derived from this software
|
||
|
|
* without specific prior written permission.
|
||
|
|
*
|
||
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
*
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Compilation Switches
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Included Files
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
#include <queue.h>
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Public Functions
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Name: sq_remlast
|
||
|
|
*
|
||
|
|
* Description:
|
||
|
|
* Removes the last entry in a singly-linked queue.
|
||
|
|
*
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
sq_entry_t *sq_remlast(sq_queue_t *queue)
|
||
|
|
{
|
||
|
|
sq_entry_t *ret = queue->tail;
|
||
|
|
|
||
|
|
if (ret)
|
||
|
|
{
|
||
|
|
if (queue->head == queue->tail)
|
||
|
|
{
|
||
|
|
queue->head = NULL;
|
||
|
|
queue->tail = NULL;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
sq_entry_t *prev;
|
||
|
|
for(prev = queue->head;
|
||
|
|
prev && prev->flink != ret;
|
||
|
|
prev = prev->flink);
|
||
|
|
|
||
|
|
if (prev)
|
||
|
|
{
|
||
|
|
prev->flink = NULL;
|
||
|
|
queue->tail = prev;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
ret->flink = NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|