1 /* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26 __pthread_setcancelstate (state
, oldstate
)
30 volatile struct pthread
*self
;
32 if (state
< PTHREAD_CANCEL_ENABLE
|| state
> PTHREAD_CANCEL_DISABLE
)
37 int oldval
= THREAD_GETMEM (self
, cancelhandling
);
40 int newval
= (state
== PTHREAD_CANCEL_DISABLE
41 ? oldval
| CANCELSTATE_BITMASK
42 : oldval
& ~CANCELSTATE_BITMASK
);
44 /* Store the old value. */
46 *oldstate
= ((oldval
& CANCELSTATE_BITMASK
)
47 ? PTHREAD_CANCEL_DISABLE
: PTHREAD_CANCEL_ENABLE
);
49 /* Avoid doing unnecessary work. The atomic operation can
50 potentially be expensive if the memory has to be locked and
51 remote cache lines have to be invalidated. */
55 /* Update the cancel handling word. This has to be done
56 atomically since other bits could be modified as well. */
57 int curval
= THREAD_ATOMIC_CMPXCHG_VAL (self
, cancelhandling
, newval
,
59 if (__builtin_expect (curval
== oldval
, 1))
61 if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval
))
67 /* Prepare for the next round. */
73 strong_alias (__pthread_setcancelstate
, pthread_setcancelstate
)