/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * $Id: XMLBufferMgr.cpp 568078 2007-08-21 11:43:25Z amassari $
 */


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

XERCES_CPP_NAMESPACE_BEGIN

// ---------------------------------------------------------------------------
//  Constructors and Destructor
// ---------------------------------------------------------------------------
XMLBufferMgr::XMLBufferMgr(MemoryManager* const manager) :

    fBufCount(32)
    , fMemoryManager(manager)
    , fBufList(0)
{
    // Allocate the buffer list and zero it out
    fBufList = (XMLBuffer**) fMemoryManager->allocate(fBufCount * sizeof(XMLBuffer*)); // 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
    fMemoryManager->deallocate(fBufList); //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 (fMemoryManager) XMLBuffer(1023, fMemoryManager);
            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
    ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::BufMgr_NoMoreBuffers, fMemoryManager);

    // 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
    ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::BufMgr_BufferNotInPool, fMemoryManager);
}

XERCES_CPP_NAMESPACE_END