src/util/BinMemInputStream.cpp

/*
 * The Apache Software License, Version 1.1
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 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
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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 01:04:05  twl
 * Initial revision
 *
 * Revision 1.2  1999/11/08 20:45:04  rahul
 * Swat for adding in Product name and CVS comment log variable.
 *
 */


// ---------------------------------------------------------------------------
//  Includes
// ---------------------------------------------------------------------------
#include <util/BinMemInputStream.hpp>
#include <memory.h>
#include <string.h>


// ---------------------------------------------------------------------------
//  BinMemInputStream: Constructors and Destructor
// ---------------------------------------------------------------------------
BinMemInputStream::BinMemInputStream(   const   XMLByte* const  initData
                                        , const unsigned int    capacity
                                        , const BufOpts         bufOpt) :
    fBuffer(0)
    , fBufOpt(bufOpt)
    , fCapacity(capacity)
    , fCurIndex(0)
{
    // According to the buffer option, do the right thing
    if (fBufOpt == BufOpt_Copy)
    {
        XMLByte* tmpBuf = new XMLByte[fCapacity];
        memcpy(tmpBuf, initData, capacity);
        fBuffer = tmpBuf;
    }
     else
    {
        fBuffer = initData;
    }
}

BinMemInputStream::~BinMemInputStream()
{
    //
    //  If we adopted or copied the buffer, then clean it up. We have to
    //  cast off the const'ness in that case in order to delete it.
    //
    if ((fBufOpt == BufOpt_Adopt) || (fBufOpt == BufOpt_Copy))
        delete [] (XMLByte*)fBuffer;
}


// ---------------------------------------------------------------------------
//  MemBinInputStream: Implementation of the input stream interface
// ---------------------------------------------------------------------------
unsigned int BinMemInputStream::readBytes(          XMLByte* const  toFill
                                            , const unsigned int    maxToRead)
{
    //
    //  Figure out how much we can really read. Its the smaller of the
    //  amount available and the amount asked for.
    //
    const unsigned int available = (fCapacity - fCurIndex);
    if (!available)
        return 0;

    const unsigned int actualToRead = available < maxToRead ?
                                      available : maxToRead;
    for (unsigned int index = 0; index < actualToRead; index++)
        toFill[index] = fBuffer[fCurIndex++];
    return actualToRead;
}