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 condition variable for thread synchronization.
19 */
20
21#include "CondVar.h"
22#include "NfcJniUtil.h"
23
24#include <cutils/log.h>
25#include <errno.h>
26#include <string.h>
27
28
29/*******************************************************************************
30**
31** Function:        CondVar
32**
33** Description:     Initialize member variables.
34**
35** Returns:         None.
36**
37*******************************************************************************/
38CondVar::CondVar ()
39{
40    pthread_condattr_t attr;
41    pthread_condattr_init(&attr);
42    pthread_condattr_setclock(&attr, CLOCK_MONOTONIC);
43    memset (&mCondition, 0, sizeof(mCondition));
44    int const res = pthread_cond_init (&mCondition, &attr);
45    if (res)
46    {
47        ALOGE ("CondVar::CondVar: fail init; error=0x%X", res);
48    }
49}
50
51
52/*******************************************************************************
53**
54** Function:        ~CondVar
55**
56** Description:     Cleanup all resources.
57**
58** Returns:         None.
59**
60*******************************************************************************/
61CondVar::~CondVar ()
62{
63    int const res = pthread_cond_destroy (&mCondition);
64    if (res)
65    {
66        ALOGE ("CondVar::~CondVar: fail destroy; error=0x%X", res);
67    }
68}
69
70
71/*******************************************************************************
72**
73** Function:        wait
74**
75** Description:     Block the caller and wait for a condition.
76**
77** Returns:         None.
78**
79*******************************************************************************/
80void CondVar::wait (Mutex& mutex)
81{
82    int const res = pthread_cond_wait (&mCondition, mutex.nativeHandle());
83    if (res)
84    {
85        ALOGE ("CondVar::wait: fail wait; error=0x%X", res);
86    }
87}
88
89
90/*******************************************************************************
91**
92** Function:        wait
93**
94** Description:     Block the caller and wait for a condition.
95**                  millisec: Timeout in milliseconds.
96**
97** Returns:         True if wait is successful; false if timeout occurs.
98**
99*******************************************************************************/
100bool CondVar::wait (Mutex& mutex, long millisec)
101{
102    bool retVal = false;
103    struct timespec absoluteTime;
104
105    if (clock_gettime (CLOCK_MONOTONIC, &absoluteTime) == -1)
106    {
107        ALOGE ("CondVar::wait: fail get time; errno=0x%X", errno);
108    }
109    else
110    {
111        absoluteTime.tv_sec += millisec / 1000;
112        long ns = absoluteTime.tv_nsec + ((millisec % 1000) * 1000000);
113        if (ns > 1000000000)
114        {
115            absoluteTime.tv_sec++;
116            absoluteTime.tv_nsec = ns - 1000000000;
117        }
118        else
119            absoluteTime.tv_nsec = ns;
120    }
121
122    int waitResult = pthread_cond_timedwait (&mCondition, mutex.nativeHandle(), &absoluteTime);
123    if ((waitResult != 0) && (waitResult != ETIMEDOUT))
124        ALOGE ("CondVar::wait: fail timed wait; error=0x%X", waitResult);
125    retVal = (waitResult == 0); //waited successfully
126    return retVal;
127}
128
129
130/*******************************************************************************
131**
132** Function:        notifyOne
133**
134** Description:     Unblock the waiting thread.
135**
136** Returns:         None.
137**
138*******************************************************************************/
139void CondVar::notifyOne ()
140{
141    int const res = pthread_cond_signal (&mCondition);
142    if (res)
143    {
144        ALOGE ("CondVar::notifyOne: fail signal; error=0x%X", res);
145    }
146}
147
148