1 /*
2 * Copyright (C) 2012 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 /*
18 * Encapsulate a mutex for thread synchronization.
19 */
20
21 #include "Mutex.h"
22 #include "NfcJniUtil.h"
23
24 #include <errno.h>
25 #include <string.h>
26
27 #include <android-base/stringprintf.h>
28 #include <base/logging.h>
29
30 using android::base::StringPrintf;
31
32 /*******************************************************************************
33 **
34 ** Function: Mutex
35 **
36 ** Description: Initialize member variables.
37 **
38 ** Returns: None.
39 **
40 *******************************************************************************/
Mutex()41 Mutex::Mutex() {
42 memset(&mMutex, 0, sizeof(mMutex));
43 int res = pthread_mutex_init(&mMutex, NULL);
44 if (res != 0) {
45 LOG(ERROR) << StringPrintf("Mutex::Mutex: fail init; error=0x%X", res);
46 }
47 }
48
49 /*******************************************************************************
50 **
51 ** Function: ~Mutex
52 **
53 ** Description: Cleanup all resources.
54 **
55 ** Returns: None.
56 **
57 *******************************************************************************/
~Mutex()58 Mutex::~Mutex() {
59 int res = pthread_mutex_destroy(&mMutex);
60 if (res != 0) {
61 LOG(ERROR) << StringPrintf("Mutex::~Mutex: fail destroy; error=0x%X", res);
62 }
63 }
64
65 /*******************************************************************************
66 **
67 ** Function: lock
68 **
69 ** Description: Block the thread and try lock the mutex.
70 **
71 ** Returns: None.
72 **
73 *******************************************************************************/
lock()74 void Mutex::lock() {
75 int res = pthread_mutex_lock(&mMutex);
76 if (res != 0) {
77 LOG(ERROR) << StringPrintf("Mutex::lock: fail lock; error=0x%X", res);
78 }
79 }
80
81 /*******************************************************************************
82 **
83 ** Function: unlock
84 **
85 ** Description: Unlock a mutex to unblock a thread.
86 **
87 ** Returns: None.
88 **
89 *******************************************************************************/
unlock()90 void Mutex::unlock() {
91 int res = pthread_mutex_unlock(&mMutex);
92 if (res != 0) {
93 LOG(ERROR) << StringPrintf("Mutex::unlock: fail unlock; error=0x%X", res);
94 }
95 }
96
97 /*******************************************************************************
98 **
99 ** Function: tryLock
100 **
101 ** Description: Try to lock the mutex.
102 **
103 ** Returns: True if the mutex is locked.
104 **
105 *******************************************************************************/
tryLock()106 bool Mutex::tryLock() {
107 int res = pthread_mutex_trylock(&mMutex);
108 if ((res != 0) && (res != EBUSY)) {
109 LOG(ERROR) << StringPrintf("Mutex::tryLock: error=0x%X", res);
110 }
111 return res == 0;
112 }
113
114 /*******************************************************************************
115 **
116 ** Function: nativeHandle
117 **
118 ** Description: Get the handle of the mutex.
119 **
120 ** Returns: Handle of the mutex.
121 **
122 *******************************************************************************/
nativeHandle()123 pthread_mutex_t* Mutex::nativeHandle() { return &mMutex; }
124