semaphore_internal.h [plain text]
#ifndef __DISPATCH_SEMAPHORE_INTERNAL__
#define __DISPATCH_SEMAPHORE_INTERNAL__
struct dispatch_queue_s;
DISPATCH_CLASS_DECL(semaphore);
struct dispatch_semaphore_s {
DISPATCH_STRUCT_HEADER(semaphore);
#if USE_MACH_SEM
semaphore_t dsema_port;
#elif USE_POSIX_SEM
sem_t dsema_sem;
#elif USE_WIN32_SEM
HANDLE dsema_handle;
#else
#error "No supported semaphore type"
#endif
long dsema_orig;
long volatile dsema_value;
union {
long volatile dsema_sent_ksignals;
long volatile dsema_group_waiters;
};
struct dispatch_continuation_s *volatile dsema_notify_head;
struct dispatch_continuation_s *volatile dsema_notify_tail;
};
DISPATCH_CLASS_DECL(group);
void _dispatch_semaphore_dispose(dispatch_object_t dou);
size_t _dispatch_semaphore_debug(dispatch_object_t dou, char *buf,
size_t bufsiz);
typedef uintptr_t _dispatch_thread_semaphore_t;
_dispatch_thread_semaphore_t _dispatch_thread_semaphore_create(void);
void _dispatch_thread_semaphore_dispose(_dispatch_thread_semaphore_t);
void _dispatch_thread_semaphore_wait(_dispatch_thread_semaphore_t);
void _dispatch_thread_semaphore_signal(_dispatch_thread_semaphore_t);
DISPATCH_ALWAYS_INLINE
static inline _dispatch_thread_semaphore_t
_dispatch_get_thread_semaphore(void)
{
_dispatch_thread_semaphore_t sema = (_dispatch_thread_semaphore_t)
_dispatch_thread_getspecific(dispatch_sema4_key);
if (slowpath(!sema)) {
return _dispatch_thread_semaphore_create();
}
_dispatch_thread_setspecific(dispatch_sema4_key, NULL);
return sema;
}
DISPATCH_ALWAYS_INLINE
static inline void
_dispatch_put_thread_semaphore(_dispatch_thread_semaphore_t sema)
{
_dispatch_thread_semaphore_t old_sema = (_dispatch_thread_semaphore_t)
_dispatch_thread_getspecific(dispatch_sema4_key);
_dispatch_thread_setspecific(dispatch_sema4_key, (void*)sema);
if (slowpath(old_sema)) {
return _dispatch_thread_semaphore_dispose(old_sema);
}
}
#endif