1 /*-------------------------------------------------------------------------
2 * drawElements Thread Library
3 * ---------------------------
4 *
5 * Copyright 2014 The Android Open Source Project
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 *//*!
20 * \file
21 * \brief Mach implementation of semaphore.
22 *//*--------------------------------------------------------------------*/
23
24 #include "deSemaphore.h"
25
26 #if (DE_OS == DE_OS_IOS || DE_OS == DE_OS_OSX)
27
28 #include "deMemory.h"
29
30 #include <mach/semaphore.h>
31 #include <mach/task.h>
32 #include <mach/mach_init.h>
33
34 DE_STATIC_ASSERT(sizeof(deSemaphore) >= sizeof(semaphore_t));
35
deSemaphore_create(int initialValue,const deSemaphoreAttributes * attributes)36 deSemaphore deSemaphore_create(int initialValue, const deSemaphoreAttributes *attributes)
37 {
38 semaphore_t sem;
39
40 DE_UNREF(attributes);
41 DE_ASSERT(initialValue >= 0);
42
43 if (semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, initialValue) != KERN_SUCCESS)
44 return 0;
45
46 return (deSemaphore)sem;
47 }
48
deSemaphore_destroy(deSemaphore semaphore)49 void deSemaphore_destroy(deSemaphore semaphore)
50 {
51 semaphore_t sem = (semaphore_t)semaphore;
52 kern_return_t res = semaphore_destroy(mach_task_self(), sem);
53 DE_ASSERT(res == 0);
54 DE_UNREF(res);
55 }
56
deSemaphore_increment(deSemaphore semaphore)57 void deSemaphore_increment(deSemaphore semaphore)
58 {
59 semaphore_t sem = (semaphore_t)semaphore;
60 kern_return_t res = semaphore_signal(sem);
61 DE_ASSERT(res == 0);
62 DE_UNREF(res);
63 }
64
deSemaphore_decrement(deSemaphore semaphore)65 void deSemaphore_decrement(deSemaphore semaphore)
66 {
67 semaphore_t sem = (semaphore_t)semaphore;
68 kern_return_t res = semaphore_wait(sem);
69 DE_ASSERT(res == 0);
70 DE_UNREF(res);
71 }
72
deSemaphore_tryDecrement(deSemaphore semaphore)73 bool deSemaphore_tryDecrement(deSemaphore semaphore)
74 {
75 semaphore_t sem = (semaphore_t)semaphore;
76 mach_timespec_t ts = {0, 1}; /* one nanosecond */
77 return (semaphore_timedwait(sem, ts) == KERN_SUCCESS);
78 }
79
80 #endif /* DE_OS */
81