fix off-by-one error in sem_(timed)wait (using old sem value instead of new)
authorRich Felker <dalias@aerifal.cx>
Mon, 7 Mar 2011 23:09:24 +0000 (18:09 -0500)
committerRich Felker <dalias@aerifal.cx>
Mon, 7 Mar 2011 23:09:24 +0000 (18:09 -0500)
src/thread/sem_timedwait.c

index e660436422de56957631f3feb2bee39a73b19690..e6c2495af75aaf2205b07068d0eea6ee43e8511b 100644 (file)
@@ -7,7 +7,7 @@ int sem_timedwait(sem_t *sem, const struct timespec *at)
 
        for (;;) {
                if (a_fetch_add(sem->__val, -1) > 0) return 0;
-               val = a_fetch_add(sem->__val, 1);
+               val = a_fetch_add(sem->__val, 1)+1;
                CANCELPT_BEGIN;
                if (val <= 0 && __timedwait(sem->__val, val, CLOCK_REALTIME, at, 0) == ETIMEDOUT) {
                        errno = ETIMEDOUT;