warlogthread.cpp

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#include "StdAfx.h"
#include "WarLogThread.h"   // class implemented

#ifndef WAR_LOG_ENGINE_H
#   include "WarLogEngine.h"
#endif

#ifndef WAR_SHUTDOWN_ENGINE_H
#   include "WarShutdownEngine.h"
#endif

#ifndef WAR_AUTO_LOCK_H
#   include "WarAutoLock.h"
#endif

#define AUTO_LOCK WarAutoLock my_lock(WarLogEngine::GetEngine().mLock);

/////////////////////////////// PUBLIC ///////////////////////////////////////

//============================= LIFECYCLE ====================================

WarLogThread::WarLogThread()
{
}// WarLogThread


WarLogThread::~WarLogThread()
{
}// ~WarLogThread


//============================= OPERATORS ====================================
//============================= OPERATIONS ===================================


void WarLogThread::PushEvent(war_logevent_ptr_t& logEventPtr)
{
    AUTO_LOCK

    mLogEvents.push_back(logEventPtr);
    mEvent.Signal();

    // Adjust the therad priority after the size of the queue
    int num_pending = mLogEvents.size();
    if (num_pending > 50000)
    {
        // Flush log entries before we use up all the the memory :/
        mLogEvents.erase(mLogEvents.begin(), mLogEvents.end());
    }
    else if (num_pending > 25000)
    {
        if (GetPriority() != WAR_THRD_PRI_HIGH)
            SetPriority(WAR_THRD_PRI_HIGH);
    }
    else if (num_pending > 10000)
    {
        if (GetPriority() != WAR_THRD_PRI_NORMAL)
            SetPriority(WAR_THRD_PRI_NORMAL);
    }
    else if (num_pending < 100)
    {
        if (GetPriority() != WAR_THRD_PRI_VERYLOW)
            SetPriority(WAR_THRD_PRI_VERYLOW);
    }
    else if (num_pending < 500)
    {
        if (GetPriority() != WAR_THRD_PRI_LOW)
            SetPriority(WAR_THRD_PRI_LOW);
    }
}

//============================= ACCESS     ===================================
//============================= INQUIRY    ===================================
/////////////////////////////// PROTECTED  ///////////////////////////////////

void WarLogThread::OnShutdown(war_cptr_t parg)
{
    ((WarLogThread *)parg)->SetExitFlag();

    WarPtrWrapper<WarLogThread> my_ptr = (WarLogThread *)parg;
    my_ptr->SetExitFlag();
    my_ptr->SetPriority(WAR_THRD_PRI_HIGH);

    while(my_ptr->IsActive())
    {
        my_ptr->mEvent.Signal();
        WarTime::Sleep(100);
    }

    // Remove the pointer from the log engine
    {
        AUTO_LOCK
        WarLogEngine::GetEngine().mLogThreadPtr = NULL;
    }

    // Wait for the thread to kill it's own reference to itself
    while(my_ptr->GetReferenceCount() > 1)
        WarTime::Sleep(100);

    my_ptr = NULL;
}

/////////////////////////////// PRIVATE    ///////////////////////////////////

void WarLogThread::Run()
{
    war_logevent_ptr_t log_event;

    WarShutdownEngine::GetEngine().AddEvent(OnShutdown, this);

    while(!IsExiting())
    {
        {
            AUTO_LOCK

            if (!mLogEvents.empty())
            {
                log_event = mLogEvents.front();
                mLogEvents.pop_front();
            }
        }

        if (log_event.IsEmpty())
            mEvent.WaitForEvent();
        else
        {

#if WAR_CATCH_ALL
            try
#endif
            {
                WarLogEngine::GetEngine().OnLogEvent(log_event);
            }
#if WAR_CATCH_ALL
            catch(...)
            {
                // Just in case...
                ;
            }
#endif
            log_event = NULL;
        }
    }
}