fix sem_timedwait bug introduced in timedwait unification

[musl] / src / thread / sem_timedwait.c

diff --git a/src/thread/sem_timedwait.c b/src/thread/sem_timedwait.c
index e6c2495..64b4342 100644 (file)
--- a/src/thread/sem_timedwait.c
+++ b/src/thread/sem_timedwait.c
@@ -1,18 +1,23 @@
 #include <semaphore.h>
 #include "pthread_impl.h"
 
-int sem_timedwait(sem_t *sem, const struct timespec *at)
+static void cleanup(void *p)
 {
-       int val;
+       a_dec(p);
+}
 
-       for (;;) {
-               if (a_fetch_add(sem->__val, -1) > 0) return 0;
-               val = a_fetch_add(sem->__val, 1)+1;
-               CANCELPT_BEGIN;
-               if (val <= 0 && __timedwait(sem->__val, val, CLOCK_REALTIME, at, 0) == ETIMEDOUT) {
-                       errno = ETIMEDOUT;
+int sem_timedwait(sem_t *sem, const struct timespec *at)
+{
+       while (sem_trywait(sem)) {
+               int r;
+               a_inc(sem->__val+1);
+               a_cas(sem->__val, 0, -1);
+               r = __timedwait(sem->__val, -1, CLOCK_REALTIME, at, cleanup, sem->__val+1, 0);
+               a_dec(sem->__val+1);
+               if (r) {
+                       errno = r;
                        return -1;
                }
-               CANCELPT_END;
        }
+       return 0;
 }