src/framework/XMLBufferMgr.cpp

/*
 * The Apache Software License, Version 1.1
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 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
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 *       "This product includes software developed by the
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 *    if and wherever such third-party acknowledgments normally appear.
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 * This software consists of voluntary contributions made by many
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/**
 * $Log$
 * Revision 1.1  1999/11/09 01:08:30  twl
 * Initial revision
 *
 * Revision 1.2  1999/11/08 20:44:36  rahul
 * Swat for adding in Product name and CVS comment log variable.
 *
 */


// ---------------------------------------------------------------------------
//  Includes
// ---------------------------------------------------------------------------
#include <memory.h>
#include <string.h>
#include <util/RuntimeException.hpp>
#include <framework/XMLBuffer.hpp>
#include <framework/XMLBufferMgr.hpp>



// ---------------------------------------------------------------------------
//  Constructors and Destructor
// ---------------------------------------------------------------------------
XMLBufferMgr::XMLBufferMgr() :

    fBufCount(32)
    , fBufList(0)
{
    // Allocate the buffer list and zero it out
    fBufList = new XMLBuffer*[fBufCount];
    for (unsigned int index = 0; index < fBufCount; index++)
        fBufList[index] = 0;
}

XMLBufferMgr::~XMLBufferMgr()
{
    // Delete any buffers that got allocated
    for (unsigned int index = 0; index < fBufCount; index++)
        delete fBufList[index];

    // And then the buffer list
    delete [] fBufList;
}


// ---------------------------------------------------------------------------
//  Buffer management
// ---------------------------------------------------------------------------
XMLBuffer& XMLBufferMgr::bidOnBuffer()
{
    //
    //  Look for a buffer that is not in use. If we hit a null entry, then
    //  we have to add one.
    //
    for (unsigned int index = 0; index < fBufCount; index++)
    {
        // No more buffers available, so create one and take it
        if (!fBufList[index])
        {
            fBufList[index] = new XMLBuffer;
            fBufList[index]->setInUse(true);
            return *fBufList[index];
        }

        //
        //  There's one here, so see if its use. If not, mark it, reset it,
        //  and take it
        //
        if (!fBufList[index]->getInUse())
        {
            fBufList[index]->reset();
            fBufList[index]->setInUse(true);
            return *(fBufList[index]);
        }
    }

    // We did not find one, so freak out
    ThrowXML(RuntimeException, XML4CExcepts::BufMgr_NoMoreBuffers);

    // NOTE: Dummy return to make some compilers happy. Never really gets called!
    return *fBufList[0];
}


void XMLBufferMgr::releaseBuffer(XMLBuffer& toRelease)
{
    // Look for this buffer in the list
    for (unsigned int index = 0; index < fBufCount; index++)
    {
        if (fBufList[index] == &toRelease)
        {
            // Unmark it
            toRelease.setInUse(false);
            return;
        }
    }

    // It was not a legal buffer
    ThrowXML(RuntimeException, XML4CExcepts::BufMgr_BufferNotInPool);
}