CppCommon  1.0.4.1
C++ Common Library
event_auto_reset.cpp
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1 
9 #include "threads/event_auto_reset.h"
10 
11 #include "errors/fatal.h"
12 #include "utility/validate_aligned_storage.h"
13 
14 #include <algorithm>
15 
16 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
17 #include <pthread.h>
18 #elif defined(_WIN32) || defined(_WIN64)
19 #include <windows.h>
20 #undef max
21 #undef min
22 #endif
23 
24 namespace CppCommon {
25 
27 
28 class EventAutoReset::Impl
29 {
30 public:
31  Impl(bool signaled)
32  {
33 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
34  int result = pthread_mutex_init(&_mutex, nullptr);
35  if (result != 0)
36  throwex SystemException("Failed to initialize a mutex for the auto-reset event!", result);
37  result = pthread_cond_init(&_cond, nullptr);
38  if (result != 0)
39  throwex SystemException("Failed to initialize a conditional variable for the auto-reset event!", result);
40  _signaled = signaled ? 1 : 0;
41 #elif defined(_WIN32) || defined(_WIN64)
42  _event = CreateEvent(nullptr, FALSE, signaled ? TRUE : FALSE, nullptr);
43  if (_event == nullptr)
44  throwex SystemException("Failed to create an auto-reset event!");
45 #endif
46  }
47 
48  ~Impl()
49  {
50 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
51  int result = pthread_mutex_destroy(&_mutex);
52  if (result != 0)
53  fatality(SystemException("Failed to destroy a mutex for the auto-reset event!", result));
54  result = pthread_cond_destroy(&_cond);
55  if (result != 0)
56  fatality(SystemException("Failed to destroy a conditional variable for the auto-reset event!", result));
57 #elif defined(_WIN32) || defined(_WIN64)
58  if (!CloseHandle(_event))
59  fatality(SystemException("Failed to close an auto-reset event!"));
60 #endif
61  }
62 
63  void Signal()
64  {
65 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
66  int result = pthread_mutex_lock(&_mutex);
67  if (result != 0)
68  throwex SystemException("Failed to lock a mutex for the auto-reset event!", result);
69  ++_signaled;
70  result = pthread_mutex_unlock(&_mutex);
71  if (result != 0)
72  throwex SystemException("Failed to unlock a mutex for the auto-reset event!", result);
73  result = pthread_cond_signal(&_cond);
74  if (result != 0)
75  throwex SystemException("Failed to signal an auto-reset event!", result);
76 #elif defined(_WIN32) || defined(_WIN64)
77  if (!SetEvent(_event))
78  throwex SystemException("Failed to signal an auto-reset event!");
79 #endif
80  }
81 
82  bool TryWait()
83  {
84 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
85  int result = pthread_mutex_lock(&_mutex);
86  if (result != 0)
87  throwex SystemException("Failed to lock a mutex for the auto-reset event!", result);
88  bool signaled = (_signaled-- > 0);
89  _signaled = (_signaled < 0) ? 0 : _signaled;
90  result = pthread_mutex_unlock(&_mutex);
91  if (result != 0)
92  throwex SystemException("Failed to unlock a mutex for the auto-reset event!", result);
93  return signaled;
94 #elif defined(_WIN32) || defined(_WIN64)
95  DWORD result = WaitForSingleObject(_event, 0);
96  if ((result != WAIT_OBJECT_0) && (result != WAIT_TIMEOUT))
97  throwex SystemException("Failed to try lock an auto-reset event!");
98  return (result == WAIT_OBJECT_0);
99 #endif
100  }
101 
102  bool TryWaitFor(const Timespan& timespan)
103  {
104  if (timespan < 0)
105  return TryWait();
106 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
107  struct timespec timeout;
108  timeout.tv_sec = timespan.seconds();
109  timeout.tv_nsec = timespan.nanoseconds() % 1000000000;
110  int result = pthread_mutex_lock(&_mutex);
111  if (result != 0)
112  throwex SystemException("Failed to lock a mutex for the auto-reset event!", result);
113  bool signaled = true;
114  while (!_signaled)
115  {
116  result = pthread_cond_timedwait(&_cond, &_mutex, &timeout);
117  if ((result != 0) && (result != ETIMEDOUT))
118  throwex SystemException("Failed to timeout waiting a conditional variable for the auto-reset event!", result);
119  if (result == ETIMEDOUT)
120  signaled = (_signaled > 0);
121  }
122  _signaled = (_signaled > 0) ? (_signaled - 1) : 0;
123  result = pthread_mutex_unlock(&_mutex);
124  if (result != 0)
125  throwex SystemException("Failed to unlock a mutex for the auto-reset event!", result);
126  return signaled;
127 #elif defined(_WIN32) || defined(_WIN64)
128  DWORD result = WaitForSingleObject(_event, std::max((DWORD)1, (DWORD)timespan.milliseconds()));
129  if ((result != WAIT_OBJECT_0) && (result != WAIT_TIMEOUT))
130  throwex SystemException("Failed to try lock an auto-reset event for the given timeout!");
131  return (result == WAIT_OBJECT_0);
132 #endif
133  }
134 
135  void Wait()
136  {
137 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
138  int result = pthread_mutex_lock(&_mutex);
139  if (result != 0)
140  throwex SystemException("Failed to lock a mutex for the auto-reset event!", result);
141  while (!_signaled)
142  {
143  result = pthread_cond_wait(&_cond, &_mutex);
144  if (result != 0)
145  throwex SystemException("Failed to waiting a conditional variable for the auto-reset event!", result);
146  }
147  _signaled = (_signaled > 0) ? (_signaled - 1) : 0;
148  result = pthread_mutex_unlock(&_mutex);
149  if (result != 0)
150  throwex SystemException("Failed to unlock a mutex for the auto-reset event!", result);
151 #elif defined(_WIN32) || defined(_WIN64)
152  DWORD result = WaitForSingleObject(_event, INFINITE);
153  if (result != WAIT_OBJECT_0)
154  throwex SystemException("Failed to lock an auto-reset event!");
155 #endif
156  }
157 
158 private:
159 #if defined(unix) || defined(__unix) || defined(__unix__) || defined(__APPLE__)
160  pthread_mutex_t _mutex;
161  pthread_cond_t _cond;
162  int _signaled;
163 #elif defined(_WIN32) || defined(_WIN64)
164  HANDLE _event;
165 #endif
166 };
167 
169 
170 EventAutoReset::EventAutoReset(bool signaled)
171 {
172  // Check implementation storage parameters
173  [[maybe_unused]] ValidateAlignedStorage<sizeof(Impl), alignof(Impl), StorageSize, StorageAlign> _;
174  static_assert((StorageSize >= sizeof(Impl)), "EventAutoReset::StorageSize must be increased!");
175  static_assert(((StorageAlign % alignof(Impl)) == 0), "EventAutoReset::StorageAlign must be adjusted!");
176 
177  // Create the implementation instance
178  new(&_storage)Impl(signaled);
179 }
180 
181 EventAutoReset::~EventAutoReset()
182 {
183  // Delete the implementation instance
184  reinterpret_cast<Impl*>(&_storage)->~Impl();
185 }
186 
187 void EventAutoReset::Signal() { impl().Signal(); }
188 
189 bool EventAutoReset::TryWait() { return impl().TryWait(); }
190 bool EventAutoReset::TryWaitFor(const Timespan& timespan) { return impl().TryWaitFor(timespan); }
191 
192 void EventAutoReset::Wait() { impl().Wait(); }
193 
194 } // namespace CppCommon
CppCommon::EventAutoReset::TryWait
bool TryWait()
Try to wait the event without block.
Definition: event_auto_reset.cpp:189
CppCommon::EventAutoReset::Wait
void Wait()
Try to wait the event with block.
Definition: event_auto_reset.cpp:192
CppCommon::EventAutoReset::Signal
void Signal()
Signal one of waiting thread about event occurred.
Definition: event_auto_reset.cpp:187
CppCommon::EventAutoReset::EventAutoReset
EventAutoReset(bool signaled=false)
Default class constructor.
Definition: event_auto_reset.cpp:170
CppCommon::EventAutoReset::TryWaitFor
bool TryWaitFor(const Timespan &timespan)
Try to wait the event for the given timespan.
Definition: event_auto_reset.cpp:190
throwex
#define throwex
Throw extended exception macro.
Definition: exceptions.h:23
event_auto_reset.h
Auto-reset event synchronization primitive definition.
fatal.h
Fatal abort execution definition.
fatality
#define fatality(...)
Fatal abort execution extended macro.
Definition: fatal.h:22
CppCommon
C++ Common project definitions.
Definition: token_bucket.h:15
validate_aligned_storage.h
Aligned storage validator definition.
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