/*************************************************************************
 *
 *  The Contents of this file are made available subject to the terms of
 *  either of the following licenses
 *
 *         - GNU Lesser General Public License Version 2.1
 *         - Sun Industry Standards Source License Version 1.1
 *
 *  Sun Microsystems Inc., October, 2000
 *
 *  GNU Lesser General Public License Version 2.1
 *  =============================================
 *  Copyright 2000 by Sun Microsystems, Inc.
 *  901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License version 2.1, as published by the Free Software Foundation.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *  MA  02111-1307  USA
 *
 *
 *  Sun Industry Standards Source License Version 1.1
 *  =================================================
 *  The contents of this file are subject to the Sun Industry Standards
 *  Source License Version 1.1 (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.openoffice.org/license.html.
 *
 *  Software provided under this License is provided on an "AS IS" basis,
 *  WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 *  WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
 *  MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
 *  See the License for the specific provisions governing your rights and
 *  obligations concerning the Software.
 *
 *  The Initial Developer of the Original Code is: IBM Corporation
 *
 *  Copyright: 2008 by IBM Corporation
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): _______________________________________
 *
 *
 ************************************************************************/
/*************************************************************************
 * @file
 *  For LWP filter architecture prototype
 ************************************************************************/

#include <lwpobjhdr.hxx>
#include <lwpobjtags.hxx>
#include <lwpdefs.hxx>
#include <lwpfilehdr.hxx>

LwpObjectHeader::LwpObjectHeader()
    : m_nTag(0)
    , m_nSize(0)
    , m_bCompressed(false)
{
}
/**
 * @descr  read header from stream
  */
bool LwpObjectHeader::Read(LwpSvStream& rStrm)
{
    sal_uInt32 nVersionID = 0;
    sal_uInt32 nRefCount = 0;
    sal_uInt32 nNextVersionOffset = 0;
    sal_uInt32 nHeaderSize = 0;

    sal_Int64 nStartPos = rStrm.Tell();

    if (LwpFileHeader::m_nFileRevision < 0x000B)
    {
        rStrm.ReadUInt32(m_nTag);
        m_ID.Read(&rStrm);
        rStrm.ReadUInt32(nVersionID);
        rStrm.ReadUInt32(nRefCount);
        rStrm.ReadUInt32(nNextVersionOffset);

        nHeaderSize = sizeof(m_nTag) + LwpObjectID::DiskSize() + sizeof(nVersionID)
                      + sizeof(nRefCount) + sizeof(nNextVersionOffset) + sizeof(m_nSize);

        if ((m_nTag == TAG_AMI) || (LwpFileHeader::m_nFileRevision < 0x0006))
        {
            sal_uInt32 nNextVersionID = 0;
            rStrm.ReadUInt32(nNextVersionID);
            nHeaderSize += sizeof(nNextVersionID);
        }
        rStrm.ReadUInt32(m_nSize);
    }
    else
    {
        sal_uInt8 nFlagBits = 0;
        sal_uInt16 VOType = 0;
        if (rStrm.remainingSize() < 3)
            return false;
        rStrm.ReadUInt16(VOType);
        rStrm.ReadUInt8(nFlagBits);

        m_nTag = static_cast<sal_uInt32>(VOType);
        m_ID.ReadIndexed(&rStrm);
        nHeaderSize = sizeof(VOType) + sizeof(nFlagBits) + m_ID.DiskSizeIndexed();

        sal_uInt8 tmpByte;
        sal_uInt16 tmpShort;
        switch (nFlagBits & VERSION_BITS)
        {
            case ONE_BYTE_VERSION:
                rStrm.ReadUInt8(tmpByte);
                nVersionID = static_cast<sal_uInt32>(tmpByte);
                nHeaderSize++;
                break;

            case TWO_BYTE_VERSION:
                rStrm.ReadUInt16(tmpShort);
                nVersionID = static_cast<sal_uInt32>(tmpShort);
                nHeaderSize += 2;
                break;

            case FOUR_BYTE_VERSION:
                rStrm.ReadUInt32(nVersionID);
                nHeaderSize += 4;
                break;
            case DEFAULT_VERSION: //fall through
            default:
                nVersionID = 2;
                break; // nothing
        }

        switch (nFlagBits & REFCOUNT_BITS)
        {
            case ONE_BYTE_REFCOUNT:
                rStrm.ReadUInt8(tmpByte);
                nRefCount = static_cast<sal_uInt32>(tmpByte);
                nHeaderSize++;
                break;

            case TWO_BYTE_REFCOUNT:
                rStrm.ReadUInt16(tmpShort);
                nRefCount = static_cast<sal_uInt32>(tmpShort);
                nHeaderSize += 2;
                break;

            case FOUR_BYTE_REFCOUNT: //through
            default:
                rStrm.ReadUInt32(nRefCount);
                nHeaderSize += 4;
                break;
        }

        if (nFlagBits & HAS_PREVOFFSET)
        {
            rStrm.ReadUInt32(nNextVersionOffset);
            nHeaderSize += 4;
        }
        else
            nNextVersionOffset = BAD_OFFSET;

        switch (nFlagBits & SIZE_BITS)
        {
            case ONE_BYTE_SIZE:
                rStrm.ReadUInt8(tmpByte);
                m_nSize = static_cast<sal_uInt32>(tmpByte);
                nHeaderSize++;
                break;

            case TWO_BYTE_SIZE:
                rStrm.ReadUInt16(tmpShort);
                m_nSize = static_cast<sal_uInt32>(tmpShort);
                nHeaderSize += 2;
                break;

            case FOUR_BYTE_SIZE: //go through
            default:
                rStrm.ReadUInt32(m_nSize);
                nHeaderSize += 4;
                break;
        }

        if (nFlagBits & DATA_COMPRESSED)
        {
            m_bCompressed = true;
        }
    }
    sal_Int64 nEndPos = rStrm.Tell();
    return rStrm.good() && (nStartPos + nHeaderSize == nEndPos);
}

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