mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-12 19:13:34 +08:00
e814f74891
* pthread_cancel.c (pthread_cancel): Use tkill directly. * sysdeps/unix/sysv/linux/pthread_kill.c (__pthread_kill): Disallow sending SIGCANCEL. tst-kill3, tst-kill4, tst-kill5. * tst-kill1.c: New file. * tst-kill2.c: New file. * tst-kill3.c: New file. * tst-kill5.c: New file. * tst-basic7.c: Renamed to... * tst-kill4.c: ...this.
79 lines
2.4 KiB
C
79 lines
2.4 KiB
C
/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
|
|
|
|
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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <errno.h>
|
|
#include <signal.h>
|
|
#include "pthreadP.h"
|
|
#include "atomic.h"
|
|
#include <sysdep.h>
|
|
|
|
|
|
int
|
|
pthread_cancel (th)
|
|
pthread_t th;
|
|
{
|
|
volatile struct pthread *pd = (volatile struct pthread *) th;
|
|
|
|
/* Make sure the descriptor is valid. */
|
|
if (INVALID_TD_P (pd))
|
|
/* Not a valid thread handle. */
|
|
return ESRCH;
|
|
|
|
int result = 0;
|
|
while (1)
|
|
{
|
|
int oldval = pd->cancelhandling;
|
|
int newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK;
|
|
|
|
/* Avoid doing unnecessary work. The atomic operation can
|
|
potentially be expensive if the bug has to be locked and
|
|
remote cache lines have to be invalidated. */
|
|
if (oldval == newval)
|
|
break;
|
|
|
|
/* If the cancellation is handled asynchronously just send a
|
|
signal. We avoid this if possible since it's more
|
|
expensive. */
|
|
if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval))
|
|
{
|
|
/* Mark the cancellation as "in progress". */
|
|
atomic_bit_set (&pd->cancelhandling, CANCELING_BIT);
|
|
|
|
/* The cancellation handler will take care of marking the
|
|
thread as canceled. */
|
|
INTERNAL_SYSCALL_DECL (err);
|
|
|
|
int val = INTERNAL_SYSCALL (tkill, err, 2, pd->tid, SIGCANCEL);
|
|
|
|
if (INTERNAL_SYSCALL_ERROR_P (val, err))
|
|
result = INTERNAL_SYSCALL_ERRNO (val, err);
|
|
|
|
break;
|
|
}
|
|
|
|
/* Mark the thread as canceled. This has to be done
|
|
atomically since other bits could be modified as well. */
|
|
if (atomic_compare_and_exchange_acq (&pd->cancelhandling, newval,
|
|
oldval) == 0)
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|