/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */

/* libwpd

 * Version: MPL 2.0 / LGPLv2.1+

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 *

 * Major Contributor(s):

 * Copyright (C) 2003 William Lachance (wrlach@gmail.com)

 * Copyright (C) 2003 Marc Maurer (uwog@uwog.net)

 * Copyright (C) 2006 Fridrich Strba (fridrich.strba@bluewin.ch)

 *

 * For minor contributions see the git repository.

 *

 * Alternatively, the contents of this file may be used under the terms

 * of the GNU Lesser General Public License Version 2.1 or later

 * (LGPLv2.1+), in which case the provisions of the LGPLv2.1+ are

 * applicable instead of those above.

 *

 * For further information visit http://libwpd.sourceforge.net

 */

/* "This product is not manufactured, approved, or supported by

 * Corel Corporation or Corel Corporation Limited."

 */

#include "WP1VariableLengthGroup.h"

#include "WP1UnsupportedVariableLengthGroup.h"

#include "WP1SetTabsGroup.h"

#include "WP1HeaderFooterGroup.h"

#include "WP1FootnoteEndnoteGroup.h"

#include "WP1PictureGroup.h"

#include "WP1FileStructure.h"

#include "libwpd_internal.h"

#include <limits>

WP1VariableLengthGroup::WP1VariableLengthGroup(unsigned char group) :

  m_group(group),

  m_size(0)

{

}

WP1VariableLengthGroup *WP1VariableLengthGroup::constructVariableLengthGroup(librevenge::RVNGInputStream *input, WPXEncryption *encryption, unsigned char group)

{

  switch (group)

  {

  case WP1_SET_TABS_GROUP:

    return new WP1SetTabsGroup(input, encryption, group);

  case WP1_HEADER_FOOTER_GROUP:

    return new WP1HeaderFooterGroup(input, encryption, group);

  case WP1_FOOTNOTE_ENDNOTE_GROUP:

    return new WP1FootnoteEndnoteGroup(input, encryption, group);

  case WP1_PICTURE_GROUP:

    return new WP1PictureGroup(input, encryption, group);

  default:

    // this is an unhandled group, just skip it

    return new WP1UnsupportedVariableLengthGroup(input, encryption, group);

  }

}

bool WP1VariableLengthGroup::isGroupConsistent(librevenge::RVNGInputStream *input, WPXEncryption *encryption, const unsigned char group)

{

  long startPosition = input->tell();

  if (startPosition < 0)

    throw FileException();

  try

  {

    unsigned size = readU32(input, encryption, true);

    if (size > ((std::numeric_limits<unsigned>::max)() / 2))

      return false;

    if (input->seek(size, librevenge::RVNG_SEEK_CUR) || input->isEnd())

    {

      input->seek(startPosition, librevenge::RVNG_SEEK_SET);

      return false;

    }

    if (size != readU32(input, encryption, true))

    {

      input->seek(startPosition, librevenge::RVNG_SEEK_SET);

      return false;

    }

    if (group != readU8(input, encryption))

    {

      input->seek(startPosition, librevenge::RVNG_SEEK_SET);

      return false;

    }

    input->seek(startPosition, librevenge::RVNG_SEEK_SET);

    return true;

  }

  catch (...)

  {

    input->seek(startPosition, librevenge::RVNG_SEEK_SET);

    return false;

  }

}

void WP1VariableLengthGroup::_read(librevenge::RVNGInputStream *input, WPXEncryption *encryption)

{

  long startPosition = input->tell();

  if (startPosition < 0)

    throw FileException();

  WPD_DEBUG_MSG(("WordPerfect: handling a variable length group\n"));

  m_size = readU32(input, encryption, true); // the length is the number of data bytes minus 4 (ie. the function codes)

  if ((long)(m_size + startPosition) < startPosition)

    throw FileException();

  WPD_DEBUG_MSG(("WordPerfect: Read variable group header (start_position: %li, size: %u)\n", startPosition, m_size));

  _readContents(input, encryption);

  if ((m_size + (unsigned long)startPosition + 4 < m_size + (unsigned long)startPosition) ||

          (m_size + (unsigned long)startPosition + 4) > ((std::numeric_limits<unsigned>::max)() / 2))

    throw FileException();

  input->seek(startPosition + m_size + 4, librevenge::RVNG_SEEK_SET);

  if (m_size != readU32(input, encryption, true))

  {

    WPD_DEBUG_MSG(("WordPerfect: Possible corruption detected. Bailing out!\n"));

    throw FileException();

  }

  if (m_group != readU8(input, encryption))

  {

    WPD_DEBUG_MSG(("WordPerfect: Possible corruption detected. Bailing out!\n"));

    throw FileException();

  }

  if ((m_size + (unsigned long)startPosition + 9 < m_size + (unsigned long)startPosition) ||

          (m_size + (unsigned long)startPosition + 9) > ((std::numeric_limits<unsigned>::max)() / 2))

    throw FileException();

  input->seek(startPosition + m_size + 9, librevenge::RVNG_SEEK_SET);

}

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