diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/thread/sem_open.c | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/src/thread/sem_open.c b/src/thread/sem_open.c index 08f98c25..ed2353c8 100644 --- a/src/thread/sem_open.c +++ b/src/thread/sem_open.c @@ -29,7 +29,7 @@ sem_t *sem_open(const char *name, int flags, ...) va_list ap; mode_t mode; unsigned value; - int fd, i, e, slot, first=1, cnt; + int fd, i, e, slot, first=1, cnt, cs; sem_t newsem; void *map; char tmp[64]; @@ -74,6 +74,8 @@ sem_t *sem_open(const char *name, int flags, ...) return SEM_FAILED; } + pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs); + for (;;) { /* If exclusive mode is not requested, try opening an * existing file first and fall back to creation. */ @@ -83,16 +85,16 @@ sem_t *sem_open(const char *name, int flags, ...) if ((map = mmap(0, sizeof(sem_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED || fstat(fd, &st) < 0) { close(fd); - return SEM_FAILED; + goto fail; } close(fd); break; } if (errno != ENOENT) - return SEM_FAILED; + goto fail; } if (!(flags & O_CREAT)) - return SEM_FAILED; + goto fail; if (first) { first = 0; va_start(ap, flags); @@ -101,7 +103,7 @@ sem_t *sem_open(const char *name, int flags, ...) va_end(ap); if (value > SEM_VALUE_MAX) { errno = EINVAL; - return SEM_FAILED; + goto fail; } sem_init(&newsem, 1, value); } @@ -112,13 +114,13 @@ sem_t *sem_open(const char *name, int flags, ...) fd = open(tmp, O_CREAT|O_EXCL|FLAGS, mode); if (fd < 0) { if (errno == EEXIST) continue; - return SEM_FAILED; + goto fail; } if (write(fd, &newsem, sizeof newsem) != sizeof newsem || fstat(fd, &st) < 0 || (map = mmap(0, sizeof(sem_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED) { close(fd); unlink(tmp); - return SEM_FAILED; + goto fail; } close(fd); if (link(tmp, name) == 0) break; @@ -128,7 +130,7 @@ sem_t *sem_open(const char *name, int flags, ...) * otherwise, next iteration will try to open the * existing file. */ if (e != EEXIST || flags == (O_CREAT|O_EXCL)) - return SEM_FAILED; + goto fail; } /* See if the newly mapped semaphore is already mapped. If @@ -138,16 +140,20 @@ sem_t *sem_open(const char *name, int flags, ...) for (i=0; i<SEM_NSEMS_MAX && semtab[i].ino != st.st_ino; i++); if (i<SEM_NSEMS_MAX) { munmap(map, sizeof(sem_t)); - semtab[i].refcnt++; - UNLOCK(lock); - return semtab[i].sem; + semtab[slot].sem = 0; + slot = i; + map = semtab[i].sem; } - semtab[slot].refcnt = 1; + semtab[slot].refcnt++; semtab[slot].sem = map; semtab[slot].ino = st.st_ino; UNLOCK(lock); - + pthread_setcancelstate(cs, 0); return map; + +fail: + pthread_setcancelstate(cs, 0); + return SEM_FAILED; } int sem_close(sem_t *sem) |