diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/sem_timedwait.c')
-rw-r--r-- | nptl/sysdeps/unix/sysv/linux/sem_timedwait.c | 68 |
1 files changed, 45 insertions, 23 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/sem_timedwait.c b/nptl/sysdeps/unix/sysv/linux/sem_timedwait.c index ef897c1e93..30f6a87df4 100644 --- a/nptl/sysdeps/unix/sysv/linux/sem_timedwait.c +++ b/nptl/sysdeps/unix/sysv/linux/sem_timedwait.c @@ -1,5 +1,5 @@ /* sem_timedwait -- wait on a semaphore. Generic futex-using version. - Copyright (C) 2003 Free Software Foundation, Inc. + Copyright (C) 2003, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003. @@ -28,28 +28,39 @@ #include <shlib-compat.h> +extern void __sem_wait_cleanup (void *arg) attribute_hidden; + + +void +attribute_hidden +__sem_wait_cleanup (void *arg) +{ + struct new_sem *isem = (struct new_sem *) arg; + + atomic_decrement (&isem->nwaiters); +} + + int sem_timedwait (sem_t *sem, const struct timespec *abstime) { - /* First check for cancellation. */ - CANCELLATION_P (THREAD_SELF); - - int *futex = (int *) sem; - int val; + struct new_sem *isem = (struct new_sem *) sem; int err; - if (*futex > 0) + if (atomic_decrement_if_positive (&isem->value) > 0) + return 0; + + if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) { - val = atomic_decrement_if_positive (futex); - if (val > 0) - return 0; + __set_errno (EINVAL); + return -1; } - err = -EINVAL; - if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) - goto error_return; + atomic_increment (&isem->nwaiters); + + pthread_cleanup_push (__sem_wait_cleanup, isem); - do + while (1) { struct timeval tv; struct timespec rt; @@ -70,7 +81,11 @@ sem_timedwait (sem_t *sem, const struct timespec *abstime) /* Already timed out? */ err = -ETIMEDOUT; if (sec < 0) - goto error_return; + { + __set_errno (ETIMEDOUT); + err = -1; + break; + } /* Do wait. */ rt.tv_sec = sec; @@ -79,21 +94,28 @@ sem_timedwait (sem_t *sem, const struct timespec *abstime) /* Enable asynchronous cancellation. Required by the standard. */ int oldtype = __pthread_enable_asynccancel (); - err = lll_futex_timed_wait (futex, 0, &rt); + err = lll_futex_timed_wait (&isem->value, 0, &rt); /* Disable asynchronous cancellation. */ __pthread_disable_asynccancel (oldtype); if (err != 0 && err != -EWOULDBLOCK) - goto error_return; + { + __set_errno (-err); + err = -1; + break; + } - val = atomic_decrement_if_positive (futex); + if (atomic_decrement_if_positive (&isem->value) > 0) + { + err = 0; + break; + } } - while (val <= 0); - return 0; + pthread_cleanup_pop (0); + + atomic_decrement (&isem->nwaiters); - error_return: - __set_errno (-err); - return -1; + return err; } |