1 /*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #pragma once
18
19 // TODO: switch to <mutex> and std::mutex when this code no longer needs
20 // to compile for pre-C++11...
21
22 #include <sys/types.h>
23
24 #if !defined(_WIN32)
25 #include <pthread.h>
26 #else
27 #include <windows.h>
28 #endif
29
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33
34 #if !defined(_WIN32)
35
36 typedef pthread_mutex_t mutex_t;
37
mutex_lock(mutex_t * lock)38 static __inline__ void mutex_lock(mutex_t* lock) {
39 pthread_mutex_lock(lock);
40 }
41
mutex_unlock(mutex_t * lock)42 static __inline__ void mutex_unlock(mutex_t* lock) {
43 pthread_mutex_unlock(lock);
44 }
45
mutex_init(mutex_t * lock)46 static __inline__ int mutex_init(mutex_t* lock) {
47 return pthread_mutex_init(lock, NULL);
48 }
49
mutex_destroy(mutex_t * lock)50 static __inline__ void mutex_destroy(mutex_t* lock) {
51 pthread_mutex_destroy(lock);
52 }
53
54 #else // !defined(_WIN32)
55
56 typedef struct {
57 int init;
58 CRITICAL_SECTION lock[1];
59 } mutex_t;
60
61 #define MUTEX_INITIALIZER { 0, {{ NULL, 0, 0, NULL, NULL, 0 }} }
62
63 static __inline__ void mutex_lock(mutex_t* lock) {
64 if (!lock->init) {
65 lock->init = 1;
66 InitializeCriticalSection( lock->lock );
67 lock->init = 2;
68 } else while (lock->init != 2) {
69 Sleep(10);
70 }
71 EnterCriticalSection(lock->lock);
72 }
73
74 static __inline__ void mutex_unlock(mutex_t* lock) {
75 LeaveCriticalSection(lock->lock);
76 }
77
78 static __inline__ int mutex_init(mutex_t* lock) {
79 InitializeCriticalSection(lock->lock);
80 lock->init = 2;
81 return 0;
82 }
83
84 static __inline__ void mutex_destroy(mutex_t* lock) {
85 if (lock->init) {
86 lock->init = 0;
87 DeleteCriticalSection(lock->lock);
88 }
89 }
90
91 #endif // !defined(_WIN32)
92
93 #ifdef __cplusplus
94 }
95 #endif
96