//
//Copyright (C) 2002-2005  3Dlabs Inc. Ltd.
//All rights reserved.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions
//are met:
//
//    Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//
//    Redistributions in binary form must reproduce the above
//    copyright notice, this list of conditions and the following
//    disclaimer in the documentation and/or other materials provided
//    with the distribution.
//
//    Neither the name of 3Dlabs Inc. Ltd. nor the names of its
//    contributors may be used to endorse or promote products derived
//    from this software without specific prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
//"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
//LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
//FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
//COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
//INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
//BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
//LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
//CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
//LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
//ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
//POSSIBILITY OF SUCH DAMAGE.
//

#define SH_EXPORTING
#include "Initialisation.h"
#include "Include/InitializeGlobals.h"
#include "Include/InitializeParseContext.h"
#include "Public/ShaderLang.h"

OS_TLSIndex GlobalProcessFlag   = OS_INVALID_TLS_INDEX;

bool InitProcess()
{
    if (GlobalProcessFlag != OS_INVALID_TLS_INDEX) {
        //
        // Function is re-entrant.
        //
        return true;
    }

    GlobalProcessFlag = OS_AllocTLSIndex();

    if (GlobalProcessFlag == OS_INVALID_TLS_INDEX) {
        assert (0 && "InitProcess(): Failed to allocate TLS area for init flag");
        return false;
    }

    if (!InitializePoolIndex()) {
        assert (0 && "InitProcess(): Failed to initalize global pool");
        return false;
    }

    if (!InitializeParseContextIndex()) {
        assert (0 && "InitProcess(): Failed to initalize parse context");
        return false;
    }

    InitThread();
    return true;
}


bool InitThread()
{
    //
    // This function is re-entrant
    //
    if (GlobalProcessFlag == OS_INVALID_TLS_INDEX) {
        assert(0 && "InitThread(): Process hasn't been initalised.");
        return false;
    }

    if (OS_GetTLSValue(GlobalProcessFlag) != 0) {
        return true;
    }

    InitializeGlobalPools();

    if(!InitializeGlobalParseContext()) 
        return false;

    if(!OS_SetTLSValue(GlobalProcessFlag, (void *)1)) {
        assert(0 && "InitThread(): Unable to set init flag.");
        return false;
    }

    return true;
}


bool DetachThread()
{
    bool retFlag = true;

    if (GlobalProcessFlag == OS_INVALID_TLS_INDEX) {
        assert(0 && "DetachThread(): Process hasn't been initalised.");
        return false;
    }

    //
    // Function is re-entrant and this thread may not have been initalised.
    //
    if (OS_GetTLSValue(GlobalProcessFlag) != 0)
    {
        if(!OS_SetTLSValue(GlobalProcessFlag, (void *)0)) {
            assert(0 && "DetachThread(): Unable to clear init flag.");
            retFlag = false;
        }

        FreeGlobalPools();

        if (!FreeParseContext())
            retFlag = false;
    }

    return retFlag;
}

bool DetachProcess()
{
    bool retFlag = true;

    if (GlobalProcessFlag == OS_INVALID_TLS_INDEX)
        return true;
    
    ShFinalize();

    retFlag = DetachThread();

    FreePoolIndex();

    if(!FreeParseContextIndex())
        retFlag = false;

    OS_FreeTLSIndex(GlobalProcessFlag);
    GlobalProcessFlag = OS_INVALID_TLS_INDEX;

    return retFlag;
}