src/semaphore_internal.h

   1 /*
   2  * Copyright (c) 2008-2013 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_APACHE_LICENSE_HEADER_START@
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  * @APPLE_APACHE_LICENSE_HEADER_END@
  19  */
  20
  21 /*
  22  * IMPORTANT: This header file describes INTERNAL interfaces to libdispatch
  23  * which are subject to change in future releases of Mac OS X. Any applications
  24  * relying on these interfaces WILL break.
  25  */
  26
  27 #ifndef __DISPATCH_SEMAPHORE_INTERNAL__
  28 #define __DISPATCH_SEMAPHORE_INTERNAL__
  29
  30 struct dispatch_queue_s;
  31
  32 #if USE_MACH_SEM
  33 #define DISPATCH_OS_SEMA_FIELD(base)    semaphore_t base##_port
  34 #elif USE_POSIX_SEM
  35 #define DISPATCH_OS_SEMA_FIELD(base)    sem_t base##_sem
  36 #elif USE_WIN32_SEM
  37 #define DISPATCH_OS_SEMA_FIELD(base)    HANDLE base##_handle
  38 #else
  39 #error "No supported semaphore type"
  40 #endif
  41
  42 #define DISPATCH_SEMAPHORE_HEADER(cls, ns) \
  43         DISPATCH_OBJECT_HEADER(cls); \
  44         long volatile ns##_value; \
  45         DISPATCH_OS_SEMA_FIELD(ns)
  46
  47 struct dispatch_semaphore_header_s {
  48         DISPATCH_SEMAPHORE_HEADER(semaphore, dsema);
  49 };
  50
  51 DISPATCH_CLASS_DECL(semaphore);
  52 struct dispatch_semaphore_s {
  53         DISPATCH_SEMAPHORE_HEADER(semaphore, dsema);
  54         long dsema_orig;
  55 };
  56
  57 DISPATCH_CLASS_DECL(group);
  58 struct dispatch_group_s {
  59         DISPATCH_SEMAPHORE_HEADER(group, dg);
  60         int volatile dg_waiters;
  61         struct dispatch_continuation_s *volatile dg_notify_head;
  62         struct dispatch_continuation_s *volatile dg_notify_tail;
  63 };
  64
  65 typedef union {
  66         struct dispatch_semaphore_header_s *_dsema_hdr;
  67         struct dispatch_semaphore_s *_dsema;
  68         struct dispatch_group_s *_dg;
  69 #if USE_OBJC
  70         dispatch_semaphore_t _objc_dsema;
  71         dispatch_group_t _objc_dg;
  72 #endif
  73 } dispatch_semaphore_class_t __attribute__((__transparent_union__));
  74
  75 dispatch_group_t _dispatch_group_create_and_enter(void);
  76 void _dispatch_group_dispose(dispatch_object_t dou);
  77 size_t _dispatch_group_debug(dispatch_object_t dou, char *buf,
  78                 size_t bufsiz);
  79
  80 void _dispatch_semaphore_dispose(dispatch_object_t dou);
  81 size_t _dispatch_semaphore_debug(dispatch_object_t dou, char *buf,
  82                 size_t bufsiz);
  83
  84 #endif