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/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* 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 John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 REGENTS 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.
*
*/
#include <errno.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
pthread_join(pthread_t pthread, void **thread_return)
{
int rval = 0;
int status;
pthread_t pthread1;
/* Check if the caller has specified an invalid thread: */
if (pthread == NULL || pthread->magic != PTHREAD_MAGIC)
/* Invalid thread: */
return(EINVAL);
/* Check if the caller has specified itself: */
if (pthread == _thread_run)
/* Avoid a deadlock condition: */
return(EDEADLK);
/* Block signals: */
_thread_kern_sig_block(&status);
/* Point to the first thread in the list: */
pthread1 = _thread_link_list;
/* Search for the thread to join to: */
while (pthread1 != NULL && pthread1 != pthread) {
/* Point to the next thread: */
pthread1 = pthread1->nxt;
}
if (pthread1 == NULL) {
/* Point to the first thread in the dead thread list: */
pthread1 = _thread_dead;
/* Search for the thread to join to: */
while (pthread1 != NULL && pthread1 != pthread) {
/* Point to the next thread: */
pthread1 = pthread1->nxt;
}
}
if (pthread1 == NULL) {
/* Return an error: */
rval = ESRCH;
/* Check if this thread has been detached: */
} else if ((pthread->attr.flags & PTHREAD_DETACHED) != 0) {
/* Return an error: */
rval = ESRCH;
}
/* Check if the thread is not dead: */
else if (pthread->state != PS_DEAD) {
/* Add the running thread to the join queue: */
_thread_queue_enq(&(pthread->join_queue), _thread_run);
/* Schedule the next thread: */
_thread_kern_sched_state(PS_JOIN, __FILE__, __LINE__);
/* Block signals again: */
_thread_kern_sig_block(NULL);
/* Check if the thread is not detached: */
if ((pthread->attr.flags & PTHREAD_DETACHED) == 0) {
/* Check if the return value is required: */
if (thread_return) {
/* Return the thread's return value: */
*thread_return = pthread->ret;
}
} else {
/* Return an error: */
rval = ESRCH;
}
} else {
/* Check if the return value is required: */
if (thread_return != NULL) {
/* Return the thread's return value: */
*thread_return = pthread->ret;
}
}
/* Unblock signals: */
_thread_kern_sig_unblock(status);
/* Return the completion status: */
return (rval);
}
#endif
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