barrier/src/lib/mt/CondVar.cpp

94 lines
2.0 KiB
C++

/*
* synergy -- mouse and keyboard sharing utility
* Copyright (C) 2012-2016 Symless Ltd.
* Copyright (C) 2002 Chris Schoeneman
*
* This package is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* found in the file LICENSE that should have accompanied this file.
*
* This package is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "mt/CondVar.h"
#include "arch/Arch.h"
#include "base/Stopwatch.h"
//
// CondVarBase
//
CondVarBase::CondVarBase(Mutex* mutex) :
m_mutex(mutex)
{
assert(m_mutex != NULL);
m_cond = ARCH->newCondVar();
}
CondVarBase::~CondVarBase()
{
ARCH->closeCondVar(m_cond);
}
void
CondVarBase::lock() const
{
m_mutex->lock();
}
void
CondVarBase::unlock() const
{
m_mutex->unlock();
}
void
CondVarBase::signal()
{
ARCH->signalCondVar(m_cond);
}
void
CondVarBase::broadcast()
{
ARCH->broadcastCondVar(m_cond);
}
bool
CondVarBase::wait(Stopwatch& timer, double timeout) const
{
double remain = timeout-timer.getTime();
// Some ARCH wait()s return prematurely, retry until really timed out
// In particular, ArchMultithreadPosix::waitCondVar() returns every 100ms
do {
// Always call wait at least once, even if remain is 0, to give
// other thread a chance to grab the mutex to avoid deadlocks on
// busy waiting.
if (remain<0.0) { remain=0.0;
}
if (wait(remain)) {
return true;
}
remain = timeout - timer.getTime();
} while (remain >= 0.0);
return false;
}
bool
CondVarBase::wait(double timeout) const
{
return ARCH->waitCondVar(m_cond, m_mutex->m_mutex, timeout);
}
Mutex*
CondVarBase::getMutex() const
{
return m_mutex;
}