glibc/htl/pt-cancel.c

63 lines
1.7 KiB
C

/* Cancel a thread.
Copyright (C) 2002-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <pt-internal.h>
int
pthread_cancel (pthread_t t)
{
int err = 0;
struct __pthread *p;
p = __pthread_getid (t);
if (p == NULL)
return ESRCH;
__pthread_mutex_lock (&p->cancel_lock);
if (p->cancel_pending)
{
__pthread_mutex_unlock (&p->cancel_lock);
return 0;
}
p->cancel_pending = 1;
if (p->cancel_state != PTHREAD_CANCEL_ENABLE)
{
__pthread_mutex_unlock (&p->cancel_lock);
return 0;
}
if (p->cancel_type == PTHREAD_CANCEL_ASYNCHRONOUS)
/* CANCEL_LOCK is unlocked by this call. */
err = __pthread_do_cancel (p);
else
{
if (p->cancel_hook != NULL)
/* Thread blocking on a cancellation point. Invoke hook to unblock.
See __pthread_cond_timedwait_internal. */
p->cancel_hook (p->cancel_hook_arg);
__pthread_mutex_unlock (&p->cancel_lock);
}
return err;
}