private/os/semaphore_private.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 #ifndef __OS_SEMAPHORE_PRIVATE__
  22 #define __OS_SEMAPHORE_PRIVATE__
  23
  24 #include <Availability.h>
  25 #include <stdint.h>
  26 #include <os/base_private.h>
  27 #include <os/tsd.h>
  28
  29 OS_ASSUME_NONNULL_BEGIN
  30
  31 __BEGIN_DECLS
  32
  33 #define OS_SEMAPHORE_SPI_VERSION 20130313
  34
  35 typedef uintptr_t os_semaphore_t;
  36
  37 __OSX_AVAILABLE_STARTING(__MAC_10_9,__IPHONE_7_0)
  38 OS_EXPORT OS_WARN_RESULT OS_NOTHROW
  39 os_semaphore_t _os_semaphore_create(void);
  40
  41 __OSX_AVAILABLE_STARTING(__MAC_10_9,__IPHONE_7_0)
  42 OS_EXPORT OS_NOTHROW
  43 void _os_semaphore_dispose(os_semaphore_t);
  44
  45 __OSX_AVAILABLE_STARTING(__MAC_10_9,__IPHONE_7_0)
  46 OS_EXPORT OS_NOTHROW
  47 void _os_semaphore_wait(os_semaphore_t);
  48
  49 __OSX_AVAILABLE_STARTING(__MAC_10_9,__IPHONE_7_0)
  50 OS_EXPORT OS_NOTHROW
  51 void _os_semaphore_signal(os_semaphore_t);
  52
  53 OS_WARN_RESULT OS_NOTHROW
  54 __header_always_inline os_semaphore_t
  55 os_get_cached_semaphore(void)
  56 {
  57         os_semaphore_t sema;
  58         sema = (os_semaphore_t)_os_tsd_get_direct(__TSD_SEMAPHORE_CACHE);
  59         if (os_unlikely(!sema)) {
  60                 return _os_semaphore_create();
  61         }
  62         _os_tsd_set_direct(__TSD_SEMAPHORE_CACHE, 0);
  63         return sema;
  64 }
  65
  66 OS_NOTHROW
  67 __header_always_inline void
  68 os_put_cached_semaphore(os_semaphore_t sema)
  69 {
  70         os_semaphore_t old_sema;
  71         old_sema = (os_semaphore_t)_os_tsd_get_direct(__TSD_SEMAPHORE_CACHE);
  72         _os_tsd_set_direct(__TSD_SEMAPHORE_CACHE, (void*)sema);
  73         if (os_unlikely(old_sema)) {
  74                 return _os_semaphore_dispose(old_sema);
  75         }
  76 }
  77
  78 OS_NOTHROW
  79 __header_always_inline void
  80 os_semaphore_wait(os_semaphore_t sema)
  81 {
  82         return _os_semaphore_wait(sema);
  83 }
  84
  85 OS_NOTHROW
  86 __header_always_inline void
  87 os_semaphore_signal(os_semaphore_t sema)
  88 {
  89         return _os_semaphore_signal(sema);
  90 }
  91
  92 __END_DECLS
  93
  94 OS_ASSUME_NONNULL_END
  95
  96 #endif // __OS_SEMAPHORE_PRIVATE__