static void
_dispatch_semaphore_create_port(semaphore_t *s4)
{
kern_return_t kr;
semaphore_t tmp;
if (*s4) {
return;
}
_dispatch_safe_fork = false;
// lazily allocate the semaphore port
// Someday:
// 1) Switch to a doubly-linked FIFO in user-space.
// 2) User-space timers for the timeout.
// 3) Use the per-thread semaphore port.
while ((kr = semaphore_create(mach_task_self(), &tmp,
SYNC_POLICY_FIFO, 0))) {
DISPATCH_VERIFY_MIG(kr);
sleep(1);
}
if (!dispatch_atomic_cmpxchg(s4, 0, tmp)) {
kr = semaphore_destroy(mach_task_self(), tmp);
DISPATCH_SEMAPHORE_VERIFY_KR(kr);
}
}
void
_voucher_dealloc_mach_voucher(mach_voucher_t kv)
{
_dispatch_kvoucher_debug("dealloc", kv);
_dispatch_voucher_debug_machport(kv);
kern_return_t kr = mach_voucher_deallocate(kv);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
}
static inline kern_return_t
_voucher_create_mach_voucher(const mach_voucher_attr_recipe_data_t *recipes,
size_t recipes_size, mach_voucher_t *kvp)
{
kern_return_t kr;
mach_port_t mhp = _dispatch_get_mach_host_port();
mach_voucher_t kv = MACH_VOUCHER_NULL;
mach_voucher_attr_raw_recipe_array_t kvr;
mach_voucher_attr_recipe_size_t kvr_size;
kvr = (mach_voucher_attr_raw_recipe_array_t)recipes;
kvr_size = (mach_voucher_attr_recipe_size_t)recipes_size;
kr = host_create_mach_voucher(mhp, kvr, kvr_size, &kv);
DISPATCH_VERIFY_MIG(kr);
if (!kr) {
_dispatch_kvoucher_debug("create", kv);
_dispatch_voucher_debug_machport(kv);
}
*kvp = kv;
return kr;
}
DISPATCH_NOINLINE
static _dispatch_thread_semaphore_t
_dispatch_thread_semaphore_create(void)
{
_dispatch_safe_fork = false;
#if USE_MACH_SEM
semaphore_t s4;
kern_return_t kr;
while (slowpath(kr = semaphore_create(mach_task_self(), &s4,
SYNC_POLICY_FIFO, 0))) {
DISPATCH_VERIFY_MIG(kr);
sleep(1);
}
return s4;
#elif USE_POSIX_SEM
sem_t *s4 = malloc(sizeof(*s4));
int ret = sem_init(s4, 0, 0);
DISPATCH_SEMAPHORE_VERIFY_RET(ret);
return (_dispatch_thread_semaphore_t) s4;
#endif
}
