Files
NazaraEngine/src/Nazara/Core/Win32/ConditionVariableImpl.cpp
Lynix ea8d683624 Updated copyright year
(532 files, wow)


Former-commit-id: cbb31f1124a86720bd3a54fe589a0f849a87b434
2015-01-21 20:53:01 +01:00

81 lines
2.2 KiB
C++

// Copyright (C) 2015 Jérôme Leclercq
// This file is part of the "Nazara Engine - Core module"
// For conditions of distribution and use, see copyright notice in Config.hpp
// Source: http://www.cs.wustl.edu/~schmidt/win32-cv-1.html
#include <Nazara/Core/Win32/ConditionVariableImpl.hpp>
#include <Nazara/Core/Win32/MutexImpl.hpp>
#include <Nazara/Core/Debug.hpp>
NzConditionVariableImpl::NzConditionVariableImpl()
{
#if NAZARA_CORE_WINDOWS_VISTA
InitializeConditionVariable(&m_cv);
#else
m_count = 0;
m_events[BROADCAST] = CreateEvent(nullptr, true, false, nullptr); // manual-reset event
m_events[SIGNAL] = CreateEvent(nullptr, false, false, nullptr); // auto-reset event
#endif
}
#if !NAZARA_CORE_WINDOWS_VISTA
NzConditionVariableImpl::~NzConditionVariableImpl()
{
CloseHandle(m_events[BROADCAST]);
CloseHandle(m_events[SIGNAL]);
}
#endif
void NzConditionVariableImpl::Signal()
{
#if NAZARA_CORE_WINDOWS_VISTA
WakeConditionVariable(&m_cv);
#else
if (m_count > 0)
SetEvent(m_events[SIGNAL]);
#endif
}
void NzConditionVariableImpl::SignalAll()
{
#if NAZARA_CORE_WINDOWS_VISTA
WakeAllConditionVariable(&m_cv);
#else
if (m_count > 0)
SetEvent(m_events[BROADCAST]);
#endif
}
void NzConditionVariableImpl::Wait(NzMutexImpl* mutex)
{
Wait(mutex, INFINITE);
}
bool NzConditionVariableImpl::Wait(NzMutexImpl* mutex, nzUInt32 timeout)
{
#if NAZARA_CORE_WINDOWS_VISTA
return SleepConditionVariableCS(&m_cv, &mutex->m_criticalSection, timeout);
#else
m_count++;
// It's ok to release the mutex here since Win32
// manual-reset events maintain state when used with SetEvent.
// This avoids the "lost wakeup" bug...
LeaveCriticalSection(&mutex->m_criticalSection);
// Wait for either event to become signaled due to Signal being called or SignalAll being called.
int result = WaitForMultipleObjects(2, m_events, false, timeout);
// Some thread called SignalAll
if (--m_count == 0 && result == WAIT_OBJECT_0 + BROADCAST)
// We're the last waiter to be notified or to stop waiting, so reset the manual event.
ResetEvent(m_events[BROADCAST]);
// Reacquire the mutex.
EnterCriticalSection(&mutex->m_criticalSection);
return result != WAIT_TIMEOUT;
#endif
}