diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/sem_wait.c')
-rw-r--r-- | nptl/sysdeps/unix/sysv/linux/sem_wait.c | 60 |
1 files changed, 57 insertions, 3 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/sem_wait.c b/nptl/sysdeps/unix/sysv/linux/sem_wait.c index d1aa97571a..e35b6480f2 100644 --- a/nptl/sysdeps/unix/sysv/linux/sem_wait.c +++ b/nptl/sysdeps/unix/sysv/linux/sem_wait.c @@ -28,9 +28,66 @@ #include <shlib-compat.h> +void +attribute_hidden +__sem_wait_cleanup (void *arg) +{ + struct new_sem *isem = (struct new_sem *) arg; + + atomic_decrement (&isem->nwaiters); +} + + int __new_sem_wait (sem_t *sem) { + struct new_sem *isem = (struct new_sem *) sem; + int err; + + if (atomic_decrement_if_positive (&isem->value) > 0) + return 0; + + atomic_increment (&isem->nwaiters); + + pthread_cleanup_push (__sem_wait_cleanup, isem); + + while (1) + { + /* Enable asynchronous cancellation. Required by the standard. */ + int oldtype = __pthread_enable_asynccancel (); + + err = lll_futex_wait (&isem->value, 0); + + /* Disable asynchronous cancellation. */ + __pthread_disable_asynccancel (oldtype); + + if (err != 0 && err != -EWOULDBLOCK) + { + __set_errno (-err); + err = -1; + } + + if (atomic_decrement_if_positive (&isem->value) > 0) + { + err = 0; + break; + } + } + + pthread_cleanup_pop (0); + + atomic_decrement (&isem->nwaiters); + + return err; +} +versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1); + + +#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1) +int +attribute_compat_text_section +__old_sem_wait (sem_t *sem) +{ int *futex = (int *) sem; int err; @@ -53,8 +110,5 @@ __new_sem_wait (sem_t *sem) return -1; } -versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1); -#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1) -strong_alias (__new_sem_wait, __old_sem_wait) compat_symbol (libpthread, __old_sem_wait, sem_wait, GLIBC_2_0); #endif |