1 /* sem_timedwait -- wait on a semaphore. Generic futex-using version.
2 Copyright (C) 2003 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
23 #include <lowlevellock.h>
24 #include <internaltypes.h>
25 #include <semaphore.h>
30 sem_timedwait (sem_t *sem, const struct timespec *abstime)
32 /* First check for cancellation. */
33 CANCELLATION_P (THREAD_SELF);
35 int *futex = (int *) sem;
41 val = atomic_decrement_if_positive (futex);
47 if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
56 /* Get the current time. */
57 gettimeofday (&tv, NULL);
59 /* Compute relative timeout. */
60 sec = abstime->tv_sec - tv.tv_sec;
61 nsec = abstime->tv_nsec - tv.tv_usec * 1000;
68 /* Already timed out? */
77 /* Enable asynchronous cancellation. Required by the standard. */
78 int oldtype = __pthread_enable_asynccancel ();
80 err = lll_futex_timed_wait (futex, 0, &rt);
82 /* Disable asynchronous cancellation. */
83 __pthread_disable_asynccancel (oldtype);
85 if (err != 0 && err != -EWOULDBLOCK)
88 val = atomic_decrement_if_positive (futex);