X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fsem_trywait.c;h=beb7aa5d3d359b793e11bf106ee21dda92feef73;hb=b2486a8922bf4977bd82c8190258e39de28c053b;hp=d0e928ef67d2048f4bbf1f1214a30407d8dbe7c8;hpb=6fc5fdbdc70dd17ea8e681a361fb4dae541ee953;p=musl

diff --git a/src/thread/sem_trywait.c b/src/thread/sem_trywait.c
index d0e928ef..beb7aa5d 100644
--- a/src/thread/sem_trywait.c
+++ b/src/thread/sem_trywait.c
@@ -3,9 +3,9 @@
 
 int sem_trywait(sem_t *sem)
 {
-	int val = a_fetch_add(sem->__val, -1);
-	if (val > 0) return 0;
-	a_inc(sem->__val);
+	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);
 	errno = EAGAIN;
 	return -1;
 }