sem_t *sem;
int refcnt;
} *semtab;
-static int lock[2];
+static volatile int lock[1];
#define FLAGS (O_RDWR|O_NOFOLLOW|O_CLOEXEC|O_NONBLOCK)
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;
}
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. */
fail:
pthread_setcancelstate(cs, 0);
+ LOCK(lock);
+ semtab[slot].sem = 0;
+ UNLOCK(lock);
return SEM_FAILED;
}