124 lines
3.8 KiB
C
124 lines
3.8 KiB
C
/* ==== queue.c ============================================================
|
|
* Copyright (c) 1993, 1994 by Chris Provenzano, proven@mit.edu
|
|
* All rights reserved.
|
|
*
|
|
* 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Chris Provenzano.
|
|
* 4. The name of Chris Provenzano may not be used to endorse or promote
|
|
* products derived from this software without specific prior written
|
|
* permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``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 CHRIS PROVENZANO 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.
|
|
*
|
|
* Description : Queue functions.
|
|
*
|
|
* 1.00 93/07/15 proven
|
|
* -Started coding this file.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static const char rcsid[] = "$Id: queue.c,v 1.3 1994/02/07 22:04:28 proven Exp $ $provenid: queue.c,v 1.16 1994/02/07 02:19:24 proven Exp $";
|
|
#endif
|
|
|
|
#include <pthread.h>
|
|
|
|
/*
|
|
* All routines in this file assume that the queue has been appropriatly
|
|
* locked.
|
|
*/
|
|
|
|
/* ==========================================================================
|
|
* pthread_queue_init()
|
|
*/
|
|
void pthread_queue_init(struct pthread_queue *queue)
|
|
{
|
|
queue->q_next = NULL;
|
|
queue->q_last = NULL;
|
|
queue->q_data = NULL;
|
|
}
|
|
|
|
/* ==========================================================================
|
|
* pthread_queue_enq()
|
|
*/
|
|
void pthread_queue_enq(struct pthread_queue *queue, struct pthread *thread)
|
|
{
|
|
if (queue->q_last) {
|
|
queue->q_last->next = thread;
|
|
} else {
|
|
queue->q_next = thread;
|
|
}
|
|
queue->q_last = thread;
|
|
thread->queue = queue;
|
|
thread->next = NULL;
|
|
|
|
}
|
|
|
|
/* ==========================================================================
|
|
* pthread_queue_get()
|
|
*/
|
|
struct pthread *pthread_queue_get(struct pthread_queue *queue)
|
|
{
|
|
return(queue->q_next);
|
|
}
|
|
|
|
/* ==========================================================================
|
|
* pthread_queue_deq()
|
|
*/
|
|
struct pthread *pthread_queue_deq(struct pthread_queue *queue)
|
|
{
|
|
struct pthread *thread = NULL;
|
|
|
|
if (queue->q_next) {
|
|
thread = queue->q_next;
|
|
if (!(queue->q_next = queue->q_next->next)) {
|
|
queue->q_last = NULL;
|
|
}
|
|
thread->queue = NULL;
|
|
thread->next = NULL;
|
|
}
|
|
return(thread);
|
|
}
|
|
|
|
/* ==========================================================================
|
|
* pthread_queue_remove()
|
|
*/
|
|
void pthread_queue_remove(struct pthread_queue *queue, struct pthread *thread)
|
|
{
|
|
struct pthread **current = &(queue->q_next);
|
|
struct pthread *prev = NULL;
|
|
|
|
while (*current) {
|
|
if (*current == thread) {
|
|
if ((*current)->next) {
|
|
*current = (*current)->next;
|
|
} else {
|
|
queue->q_last = prev;
|
|
*current = NULL;
|
|
}
|
|
}
|
|
prev = *current;
|
|
current = &((*current)->next);
|
|
}
|
|
thread->queue = NULL;
|
|
thread->next = NULL;
|
|
}
|