1 /*
2  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "condition_variable_posix.h"
12 
13 #if defined(WEBRTC_LINUX)
14 #include <ctime>
15 #else
16 #include <sys/time.h>
17 #endif
18 
19 #include <errno.h>
20 
21 #include "critical_section_posix.h"
22 
23 namespace webrtc {
Create()24 ConditionVariableWrapper* ConditionVariablePosix::Create()
25 {
26     ConditionVariablePosix* ptr = new ConditionVariablePosix;
27     if (!ptr)
28     {
29         return NULL;
30     }
31 
32     const int error = ptr->Construct();
33     if (error)
34     {
35         delete ptr;
36         return NULL;
37     }
38 
39     return ptr;
40 }
41 
ConditionVariablePosix()42 ConditionVariablePosix::ConditionVariablePosix()
43 {
44 }
45 
Construct()46 int ConditionVariablePosix::Construct()
47 {
48     int result = 0;
49 #ifdef WEBRTC_CLOCK_TYPE_REALTIME
50     result = pthread_cond_init(&_cond, NULL);
51 #else
52     pthread_condattr_t condAttr;
53     result = pthread_condattr_init(&condAttr);
54     if (result != 0)
55     {
56         return -1;
57     }
58     result = pthread_condattr_setclock(&condAttr, CLOCK_MONOTONIC);
59     if (result != 0)
60     {
61         return -1;
62     }
63     result = pthread_cond_init(&_cond, &condAttr);
64     if (result != 0)
65     {
66         return -1;
67     }
68     result = pthread_condattr_destroy(&condAttr);
69     if (result != 0)
70     {
71         return -1;
72     }
73 #endif
74     return 0;
75 }
76 
~ConditionVariablePosix()77 ConditionVariablePosix::~ConditionVariablePosix()
78 {
79     pthread_cond_destroy(&_cond);
80 }
81 
SleepCS(CriticalSectionWrapper & critSect)82 void ConditionVariablePosix::SleepCS(CriticalSectionWrapper& critSect)
83 {
84     CriticalSectionPosix* cs = reinterpret_cast<CriticalSectionPosix*>(
85                                    &critSect);
86     pthread_cond_wait(&_cond, &cs->_mutex);
87 }
88 
89 
90 bool
SleepCS(CriticalSectionWrapper & critSect,unsigned long maxTimeInMS)91 ConditionVariablePosix::SleepCS(
92     CriticalSectionWrapper& critSect,
93     unsigned long maxTimeInMS)
94 {
95     const unsigned long INFINITE =  0xFFFFFFFF;
96 
97     const int MILLISECONDS_PER_SECOND      = 1000;
98 #ifndef WEBRTC_LINUX
99     const int MICROSECONDS_PER_MILLISECOND = 1000;
100 #endif
101     const int NANOSECONDS_PER_SECOND       = 1000000000;
102     const int NANOSECONDS_PER_MILLISECOND  = 1000000;
103 
104     CriticalSectionPosix* cs = reinterpret_cast<CriticalSectionPosix*>(
105                                    &critSect);
106 
107     if (maxTimeInMS != INFINITE)
108     {
109         timespec ts;
110 #ifndef WEBRTC_MAC
111 #ifdef WEBRTC_CLOCK_TYPE_REALTIME
112         clock_gettime(CLOCK_REALTIME, &ts);
113 #else
114         clock_gettime(CLOCK_MONOTONIC, &ts);
115 #endif
116 #else
117         struct timeval tv;
118         gettimeofday(&tv, 0);
119         ts.tv_sec  = tv.tv_sec;
120         ts.tv_nsec = tv.tv_usec * MICROSECONDS_PER_MILLISECOND;
121 #endif
122 
123         ts.tv_sec += maxTimeInMS / MILLISECONDS_PER_SECOND;
124         ts.tv_nsec += (maxTimeInMS - ((maxTimeInMS / MILLISECONDS_PER_SECOND)*
125                       MILLISECONDS_PER_SECOND)) * NANOSECONDS_PER_MILLISECOND;
126 
127         if (ts.tv_nsec >= NANOSECONDS_PER_SECOND)
128         {
129             ts.tv_sec += ts.tv_nsec / NANOSECONDS_PER_SECOND;
130             ts.tv_nsec %= NANOSECONDS_PER_SECOND;
131         }
132         const int res = pthread_cond_timedwait(&_cond, &cs->_mutex, &ts);
133         return (res == ETIMEDOUT) ? false : true;
134     }
135     else
136     {
137         pthread_cond_wait(&_cond, &cs->_mutex);
138         return true;
139     }
140 }
141 
Wake()142 void ConditionVariablePosix::Wake()
143 {
144     pthread_cond_signal(&_cond);
145 }
146 
WakeAll()147 void ConditionVariablePosix::WakeAll()
148 {
149     pthread_cond_broadcast(&_cond);
150 }
151 } // namespace webrtc
152