X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fsem_open.c;h=fda0acd35c717992e44b4c5191e6f400d1190532;hb=53cd8c5a29b57ef3776ce152e00544752f3ce790;hp=ed2353c8ba3afd9ef12b3211c322dfa92ddd805a;hpb=e44849f5cf331e655705b18d6c81c616e29d50d0;p=musl

diff --git a/src/thread/sem_open.c b/src/thread/sem_open.c
index ed2353c8..fda0acd3 100644
--- a/src/thread/sem_open.c
+++ b/src/thread/sem_open.c
@@ -20,7 +20,7 @@ static struct {
 	sem_t *sem;
 	int refcnt;
 } *semtab;
-static int lock[2];
+static volatile int lock[2];
 
 #define FLAGS (O_RDWR|O_NOFOLLOW|O_CLOEXEC|O_NONBLOCK)
 
@@ -67,23 +67,23 @@ sem_t *sem_open(const char *name, int flags, ...)
 
 	flags &= (O_CREAT|O_EXCL);
 
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+
 	/* Early failure check for exclusive open; otherwise the case
 	 * where the semaphore already exists is expensive. */
 	if (flags == (O_CREAT|O_EXCL) && access(name, F_OK) == 0) {
 		errno = EEXIST;
-		return SEM_FAILED;
+		goto fail;
 	}
 
-	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
-
 	for (;;) {
 		/* If exclusive mode is not requested, try opening an
 		 * existing file first and fall back to creation. */
 		if (flags != (O_CREAT|O_EXCL)) {
 			fd = open(name, FLAGS);
 			if (fd >= 0) {
-				if ((map = mmap(0, sizeof(sem_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED ||
-				    fstat(fd, &st) < 0) {
+				if (fstat(fd, &st) < 0 ||
+				    (map = mmap(0, sizeof(sem_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED) {
 					close(fd);
 					goto fail;
 				}
@@ -123,9 +123,10 @@ sem_t *sem_open(const char *name, int flags, ...)
 			goto fail;
 		}
 		close(fd);
-		if (link(tmp, name) == 0) break;
-		e = errno;
+		e = link(tmp, name) ? errno : 0;
 		unlink(tmp);
+		if (!e) break;
+		munmap(map, sizeof(sem_t));
 		/* Failure is only fatal when doing an exclusive open;
 		 * otherwise, next iteration will try to open the
 		 * existing file. */
@@ -153,6 +154,9 @@ sem_t *sem_open(const char *name, int flags, ...)
 
 fail:
 	pthread_setcancelstate(cs, 0);
+	LOCK(lock);
+	semtab[slot].sem = 0;
+	UNLOCK(lock);
 	return SEM_FAILED;
 }