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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
*
* 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.
*/
#include <errno.h>
#include "private/bionic_futex.h"
#include "pthread_accessor.h"
int pthread_join(pthread_t t, void** return_value) {
if (t == pthread_self()) {
return EDEADLK;
}
pid_t tid;
volatile int* tid_ptr;
{
pthread_accessor thread(t);
if (thread.get() == NULL) {
return ESRCH;
}
if ((thread->attr.flags & PTHREAD_ATTR_FLAG_DETACHED) != 0) {
return EINVAL;
}
if ((thread->attr.flags & PTHREAD_ATTR_FLAG_JOINED) != 0) {
return EINVAL;
}
// Okay, looks like we can signal our intention to join.
thread->attr.flags |= PTHREAD_ATTR_FLAG_JOINED;
tid = thread->tid;
tid_ptr = &thread->tid;
}
// We set the PTHREAD_ATTR_FLAG_JOINED flag with the lock held,
// so no one is going to remove this thread except us.
// Wait for the thread to actually exit, if it hasn't already.
while (*tid_ptr != 0) {
__futex_wait(tid_ptr, tid, NULL);
}
// Take the lock again so we can pull the thread's return value
// and remove the thread from the list.
pthread_accessor thread(t);
if (return_value) {
*return_value = thread->return_value;
}
_pthread_internal_remove_locked(thread.get(), true);
return 0;
}
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