X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fsem_trywait.c;h=dd8f57e36a0bd54a60a5b4c21516b9a1b6a8bba5;hb=e8dbf00a789e3b56ca6c3d88e8048b7b2c18b797;hp=beb7aa5d3d359b793e11bf106ee21dda92feef73;hpb=a113434cd68ce30642c4995b1caadcd084be6f09;p=musl diff --git a/src/thread/sem_trywait.c b/src/thread/sem_trywait.c index beb7aa5d..dd8f57e3 100644 --- a/src/thread/sem_trywait.c +++ b/src/thread/sem_trywait.c @@ -3,9 +3,8 @@ int sem_trywait(sem_t *sem) { - if (a_fetch_add(sem->__val, -1) > 0) return 0; - if (!a_fetch_add(sem->__val, 1) && sem->__val[1]) - __wake(sem->__val, 1, 0); + int val = sem->__val[0]; + if (val>0 && a_cas(sem->__val, val, val-1)==val) return 0; errno = EAGAIN; return -1; }