//
//  csemaphore.cpp
//  xlxd
//
//  Created by Jean-Luc Deltombe (LX3JL) on 16/04/2017.
//  Copyright © 2015 Jean-Luc Deltombe (LX3JL). All rights reserved.
//
// ----------------------------------------------------------------------------
//    This file is part of xlxd.
//
//    xlxd is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation, either version 3 of the License, or
//    (at your option) any later version.
//
//    xlxd 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 Foobar.  If not, see <http://www.gnu.org/licenses/>.
// ----------------------------------------------------------------------------

#include "main.h"
#include "csemaphore.h"

////////////////////////////////////////////////////////////////////////////////////////
// constructor

CSemaphore::CSemaphore()
{
    // Initialized as locked.
    m_Count = 0;
}

////////////////////////////////////////////////////////////////////////////////////////
// operation

void CSemaphore::Reset(void)
{
    std::unique_lock<decltype(m_Mutex)> lock(m_Mutex);
    m_Count = 0;
}

void CSemaphore::Notify(void)
{
    std::unique_lock<std::mutex> lock(m_Mutex);
    m_Count++;
    m_Condition.notify_one();
}

void CSemaphore::Wait(void)
{
    std::unique_lock<std::mutex> lock(m_Mutex);
    m_Condition.wait(lock, [&]{ return m_Count > 0; });
    m_Count--;
}

bool CSemaphore::WaitFor(uint ms)
{
    std::chrono::milliseconds timespan(ms);
    std::unique_lock<decltype(m_Mutex)> lock(m_Mutex);
    auto ok = m_Condition.wait_for(lock, timespan, [&]{ return m_Count > 0; });
    if ( ok )
    {
        m_Count--;
    }
    return ok;
    
}