src/xercesc/framework/MemBufFormatTarget.cpp

/*
 * 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.
 */

/*
 * $Id$
 */

#include <xercesc/framework/MemBufFormatTarget.hpp>
#include <xercesc/util/XMLString.hpp>
#include <cstring>

namespace XERCES_CPP_NAMESPACE {

MemBufFormatTarget::MemBufFormatTarget( XMLSize_t            initCapacity
                                      , MemoryManager* const manager)
    : fMemoryManager(manager)
    , fDataBuf(0)
    , fIndex(0)
    , fCapacity(initCapacity)
{
    // Buffer is one larger than capacity, to allow for zero term
    fDataBuf = (XMLByte*) fMemoryManager->allocate
    (
        (fCapacity + 4) * sizeof(XMLByte)
    );//new XMLByte[fCapacity+4];

    // Keep it null terminated
    fDataBuf[0] = XMLByte(0);
}

MemBufFormatTarget::~MemBufFormatTarget()
{
    fMemoryManager->deallocate(fDataBuf);//delete [] fDataBuf;
}

void MemBufFormatTarget::writeChars(const XMLByte* const toWrite
                                  , const XMLSize_t      count
                                  , XMLFormatter * const)
{

    if (count)
    {
      if (fIndex + count >= fCapacity)
        ensureCapacity(count);

      memcpy(&fDataBuf[fIndex], toWrite, count * sizeof(XMLByte));
      fIndex += count;
    }

}

const XMLByte* MemBufFormatTarget::getRawBuffer() const
{
    fDataBuf[fIndex] = 0;
    fDataBuf[fIndex + 1] = 0;
    fDataBuf[fIndex + 2] = 0;
    fDataBuf[fIndex + 3] = 0;
    return fDataBuf;
}

void MemBufFormatTarget::reset()
{
    fIndex = 0;
    fDataBuf[0] = 0;
    fDataBuf[fIndex + 1] = 0;
    fDataBuf[fIndex + 2] = 0;
    fDataBuf[fIndex + 3] = 0;
}

// ---------------------------------------------------------------------------
//  MemBufFormatTarget: Private helper methods
// ---------------------------------------------------------------------------
void MemBufFormatTarget::ensureCapacity(const XMLSize_t extraNeeded)
{
    // Oops, not enough room. Calc new capacity and allocate new buffer
    const XMLSize_t newCap = ((fIndex + extraNeeded) * 2);
    XMLByte* newBuf = (XMLByte*) fMemoryManager->allocate
    (
        (newCap+4) * sizeof(XMLByte)
    );//new XMLByte[newCap+4];

    // Copy over the old stuff
    memcpy(newBuf, fDataBuf, fIndex * sizeof(XMLByte));

    // Clean up old buffer and store new stuff
    fMemoryManager->deallocate(fDataBuf); //delete [] fDataBuf;
    fDataBuf = newBuf;
    fCapacity = newCap;
}

}