/* ==== pthread_join.c =======================================================
* Copyright (c) 1994 by Chris Provenzano, proven@mit.edu
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* 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
* 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
* Description : pthread_join function.
* -Started coding this file.
/* ==========================================================================
int pthread_join(pthread_t pthread
, void **thread_return
)
plock
= &(pthread
->lock
);
while (SEMAPHORE_TEST_AND_SET(plock
)) {
/* Check that thread isn't detached already */
if (pthread
->flags
& PF_DETACHED
) {
lock
= &(pthread_run
->lock
);
while (SEMAPHORE_TEST_AND_SET(lock
)) {
/* If OK then queue current thread. */
pthread_queue(&(pthread
->join_queue
), pthread_run
);
* At this point the thread is locked from the pthread_exit
* and so are we, so no extra locking is required, but be sure
* to unlock at least ourself.
if (!(pthread
->flags
& PF_DETACHED
)) {
*thread_return
= pthread
->ret
;
pthread
->flags
|= PF_DETACHED
;
/* Cant do a cleanup until queue is cleared */
struct pthread
* next_thread
;
if (next_thread
= pthread_queue_get(&(pthread
->join_queue
))) {
next_lock
= &(next_thread
->lock
);
while (SEMAPHORE_TEST_AND_SET(next_lock
)) {
pthread_queue_deq(&(pthread
->join_queue
));
next_thread
->state
= PS_RUNNING
;
* Thread will wake up in pthread_join(), see the thread
* it was joined to already detached and unlock itself