easy7zip/CPP/7zip/Archive/Cab/CabHandler.cpp

// CabHandler.cpp

#include "StdAfx.h"

#include "Common/StringConvert.h"
#include "Common/Defs.h"
#include "Common/UTFConvert.h"
#include "Common/ComTry.h"
#include "Common/IntToString.h"

#include "Windows/PropVariant.h"
#include "Windows/Time.h"

#include "CabHandler.h"
#include "CabBlockInStream.h"

#include "../../Compress/Copy/CopyCoder.h"
#include "../../Compress/Deflate/DeflateDecoder.h"
#include "../../Compress/Lzx/LzxDecoder.h"
#include "../../Compress/Quantum/QuantumDecoder.h"

#include "../Common/ItemNameUtils.h"

using namespace NWindows;

namespace NArchive {
namespace NCab {

// #define _CAB_DETAILS

#ifdef _CAB_DETAILS
enum 
{
  kpidBlockReal = kpidUserDefined,
  kpidOffset,
  kpidVolume,
};
#endif

STATPROPSTG kProperties[] = 
{
  { NULL, kpidPath, VT_BSTR},
  // { NULL, kpidIsFolder, VT_BOOL},
  { NULL, kpidSize, VT_UI8},
  { NULL, kpidLastWriteTime, VT_FILETIME},
  { NULL, kpidAttributes, VT_UI4},
  { NULL, kpidMethod, VT_BSTR},
  { NULL, kpidBlock, VT_I4}
  #ifdef _CAB_DETAILS
  ,
  { L"BlockReal", kpidBlockReal, VT_UI4},
  { L"Offset", kpidOffset, VT_UI4},
  { L"Volume", kpidVolume, VT_UI4}
  #endif
};

static const wchar_t *kMethods[] = 
{
  L"None",
  L"MSZip",
  L"Quantum",
  L"LZX"
};

static const int kNumMethods = sizeof(kMethods) / sizeof(kMethods[0]);
static const wchar_t *kUnknownMethod = L"Unknown";

STDMETHODIMP CHandler::GetArchiveProperty(PROPID /* propID */, PROPVARIANT *value)
{
  value->vt = VT_EMPTY;
  return S_OK;
}

STDMETHODIMP CHandler::GetNumberOfProperties(UInt32 *numProperties)
{
  *numProperties = sizeof(kProperties) / sizeof(kProperties[0]);
  return S_OK;
}

STDMETHODIMP CHandler::GetPropertyInfo(UInt32 index,     
      BSTR *name, PROPID *propID, VARTYPE *varType)
{
  if(index >= sizeof(kProperties) / sizeof(kProperties[0]))
    return E_INVALIDARG;
  const STATPROPSTG &srcItem = kProperties[index];
  *propID = srcItem.propid;
  *varType = srcItem.vt;
  if (srcItem.lpwstrName == 0)
    *name = 0;
  else
    *name = ::SysAllocString(srcItem.lpwstrName);
  return S_OK;
}

STDMETHODIMP CHandler::GetNumberOfArchiveProperties(UInt32 *numProperties)
{
  *numProperties = 0;
  return S_OK;
}

STDMETHODIMP CHandler::GetArchivePropertyInfo(UInt32 /* index */,     
      BSTR * /* name */, PROPID * /* propID */, VARTYPE * /* varType */)
{
  return E_INVALIDARG;
}

STDMETHODIMP CHandler::GetProperty(UInt32 index, PROPID propID,  PROPVARIANT *value)
{
  COM_TRY_BEGIN
  NWindows::NCOM::CPropVariant propVariant;
  
  const CMvItem &mvItem = m_Database.Items[index];
  const CDatabaseEx &db = m_Database.Volumes[mvItem.VolumeIndex];
  int itemIndex = mvItem.ItemIndex;
  const CItem &item = db.Items[itemIndex];
  switch(propID)
  {
    case kpidPath:
    {
      UString unicodeName;
      if (item.IsNameUTF())
        ConvertUTF8ToUnicode(item.Name, unicodeName);
      else
        unicodeName = MultiByteToUnicodeString(item.Name, CP_ACP);
      propVariant = (const wchar_t *)NItemName::WinNameToOSName(unicodeName);
      break;
    }
    case kpidIsFolder:
      propVariant = item.IsDirectory();
      break;
    case kpidSize:
      propVariant = item.Size;
      break;
    case kpidLastWriteTime:
    {
      FILETIME localFileTime, utcFileTime;
      if (NTime::DosTimeToFileTime(item.Time, localFileTime))
      {
        if (!LocalFileTimeToFileTime(&localFileTime, &utcFileTime))
          utcFileTime.dwHighDateTime = utcFileTime.dwLowDateTime = 0;
      }
      else
        utcFileTime.dwHighDateTime = utcFileTime.dwLowDateTime = 0;
      propVariant = utcFileTime;
      break;
    }
    case kpidAttributes:
      propVariant = item.GetWinAttributes();
      break;

    case kpidMethod:
    {
      UInt32 realFolderIndex = item.GetFolderIndex(db.Folders.Size());
      const CFolder &folder = db.Folders[realFolderIndex];
      int methodIndex = folder.GetCompressionMethod();
      UString method = (methodIndex < kNumMethods) ? kMethods[methodIndex] : kUnknownMethod;
      if (methodIndex == NHeader::NCompressionMethodMajor::kLZX || 
        methodIndex == NHeader::NCompressionMethodMajor::kQuantum)
      {
        method += L":";
        wchar_t temp[32];
        ConvertUInt64ToString(folder.CompressionTypeMinor, temp);
        method += temp;
      }
      propVariant = method;
      break;
    }
    case kpidBlock:
      propVariant = (Int32)m_Database.GetFolderIndex(&mvItem);
      break;
    
    #ifdef _CAB_DETAILS
    
    case kpidBlockReal:
      propVariant = UInt32(item.FolderIndex);
      break;
    case kpidOffset:
      propVariant = (UInt32)item.Offset;
      break;
    case kpidVolume:
      propVariant = (UInt32)mvItem.VolumeIndex;
      break;
    
    #endif
  }
  propVariant.Detach(value);
  return S_OK;
  COM_TRY_END
}

/*
class CPropgressImp: public CProgressVirt
{
  CMyComPtr<IArchiveOpenCallback> m_OpenArchiveCallback;
public:
  STDMETHOD(SetTotal)(const UInt64 *numFiles);
  STDMETHOD(SetCompleted)(const UInt64 *numFiles);
  void Init(IArchiveOpenCallback *openArchiveCallback)
    { m_OpenArchiveCallback = openArchiveCallback; }
};

STDMETHODIMP CPropgressImp::SetTotal(const UInt64 *numFiles)
{
  if (m_OpenArchiveCallback)
    return m_OpenArchiveCallback->SetCompleted(numFiles, NULL);
  return S_OK;
}

STDMETHODIMP CPropgressImp::SetCompleted(const UInt64 *numFiles)
{
  if (m_OpenArchiveCallback)
    return m_OpenArchiveCallback->SetCompleted(numFiles, NULL);
  return S_OK;
}
*/

STDMETHODIMP CHandler::Open(IInStream *inStream, 
    const UInt64 *maxCheckStartPosition,
    IArchiveOpenCallback *openArchiveCallback)
{
  COM_TRY_BEGIN
  Close();
  HRESULT res = S_FALSE;
  CInArchive archive;
  CMyComPtr<IArchiveOpenVolumeCallback> openVolumeCallback;
  {
    CMyComPtr<IArchiveOpenCallback> openArchiveCallbackWrap = openArchiveCallback;
    openArchiveCallbackWrap.QueryInterface(IID_IArchiveOpenVolumeCallback, &openVolumeCallback);
  }

  CMyComPtr<IInStream> nextStream = inStream;
  bool prevChecked = false;
  UInt64 numItems = 0;
  try
  {
    while(nextStream != 0)
    {
      CDatabaseEx db;
      db.Stream = nextStream;
      res = archive.Open(maxCheckStartPosition, db);
      if (res == S_OK)
      {
        if (!m_Database.Volumes.IsEmpty())
        {
          const CDatabaseEx &dbPrev = m_Database.Volumes[prevChecked ? m_Database.Volumes.Size() - 1 : 0];
          if (dbPrev.ArchiveInfo.SetID != db.ArchiveInfo.SetID ||
              dbPrev.ArchiveInfo.CabinetNumber + (prevChecked ? 1: - 1) != 
              db.ArchiveInfo.CabinetNumber)
            res = S_FALSE;
        }
      }
      if (res == S_OK)
        m_Database.Volumes.Insert(prevChecked ? m_Database.Volumes.Size() : 0, db);
      else if (res != S_FALSE)
        return res;
      else 
      {
        if (m_Database.Volumes.IsEmpty())
          return S_FALSE;
        if (prevChecked)
          break;
        prevChecked = true;
      }

      numItems += db.Items.Size();
      RINOK(openArchiveCallback->SetCompleted(&numItems, NULL));
        
      nextStream = 0;
      for (;;)
      {
        const COtherArchive *otherArchive = 0;
        if (!prevChecked)
        {
          const CInArchiveInfo &ai = m_Database.Volumes.Front().ArchiveInfo;
          if (ai.IsTherePrev())
            otherArchive = &ai.PreviousArchive;
          else
            prevChecked = true;
        }
        if (otherArchive == 0)
        {
          const CInArchiveInfo &ai = m_Database.Volumes.Back().ArchiveInfo;
          if (ai.IsThereNext())
            otherArchive = &ai.NextArchive;
        }
        if (!otherArchive)
          break;
        const UString fullName = MultiByteToUnicodeString(otherArchive->FileName, CP_ACP);
        HRESULT result = openVolumeCallback->GetStream(fullName, &nextStream);
        if (result == S_OK)
          break;
        if (result != S_FALSE)
          return result;
        if (prevChecked)
          break;
        prevChecked = true;
      }
    }
    if (res == S_OK)
    {
      m_Database.FillSortAndShrink();
      if (!m_Database.Check())
        res = S_FALSE;
    }
  }
  catch(...)
  {
    res = S_FALSE;
  }
  if (res != S_OK)
  {
    Close();
    return res;
  }
  COM_TRY_END
  return S_OK;
}

STDMETHODIMP CHandler::Close()
{
  m_Database.Clear();
  return S_OK;
}

class CCabFolderOutStream: 
  public ISequentialOutStream,
  public CMyUnknownImp
{
public:
  MY_UNKNOWN_IMP

  STDMETHOD(Write)(const void *data, UInt32 size, UInt32 *processedSize);
private:
  const CMvDatabaseEx *m_Database;
  const CRecordVector<bool> *m_ExtractStatuses;
  int m_StartIndex;
  int m_CurrentIndex;
  CMyComPtr<IArchiveExtractCallback> m_ExtractCallback;
  bool m_TestMode;

  CMyComPtr<ISequentialOutStream> m_RealOutStream;

  bool m_IsOk;
  bool m_FileIsOpen;
  UInt64 m_RemainFileSize;
  UInt64 m_FolderSize;
  UInt64 m_PosInFolder;

  HRESULT OpenFile();
  HRESULT Write2(const void *data, UInt32 size, UInt32 *processedSize, bool isOK);
public:
  HRESULT WriteEmptyFiles();

  void Init(
      const CMvDatabaseEx *database,
      const CRecordVector<bool> *extractStatuses, 
      int startIndex, 
      UInt64 folderSize,
      IArchiveExtractCallback *extractCallback,
      bool testMode);
  HRESULT FlushCorrupted();
  HRESULT Unsupported();

  UInt64 GetRemain() const { return m_FolderSize - m_PosInFolder; }
  UInt64 GetPosInFolder() const { return m_PosInFolder; }
};

void CCabFolderOutStream::Init(
    const CMvDatabaseEx *database,
    const CRecordVector<bool> *extractStatuses, 
    int startIndex, 
    UInt64 folderSize,
    IArchiveExtractCallback *extractCallback,
    bool testMode)
{
  m_Database = database;
  m_ExtractStatuses = extractStatuses;
  m_StartIndex = startIndex;
  m_FolderSize = folderSize;

  m_ExtractCallback = extractCallback;
  m_TestMode = testMode;

  m_CurrentIndex = 0;
  m_PosInFolder = 0;
  m_FileIsOpen = false;
  m_IsOk = true;
}

HRESULT CCabFolderOutStream::OpenFile()
{
  Int32 askMode = (*m_ExtractStatuses)[m_CurrentIndex] ? (m_TestMode ? 
      NExtract::NAskMode::kTest :
      NExtract::NAskMode::kExtract) :
      NExtract::NAskMode::kSkip;
  RINOK(m_ExtractCallback->GetStream(m_StartIndex + m_CurrentIndex, &m_RealOutStream, askMode));
  if (!m_RealOutStream && !m_TestMode)
    askMode = NArchive::NExtract::NAskMode::kSkip;
  return m_ExtractCallback->PrepareOperation(askMode);
}

HRESULT CCabFolderOutStream::WriteEmptyFiles()
{
  if (m_FileIsOpen)
    return S_OK;
  for(;m_CurrentIndex < m_ExtractStatuses->Size(); m_CurrentIndex++)
  {
    const CMvItem &mvItem = m_Database->Items[m_StartIndex + m_CurrentIndex];
    const CItem &item = m_Database->Volumes[mvItem.VolumeIndex].Items[mvItem.ItemIndex];
    UInt64 fileSize = item.Size;
    if (fileSize != 0)
      return S_OK;
    HRESULT result = OpenFile();
    m_RealOutStream.Release();
    RINOK(result);
    RINOK(m_ExtractCallback->SetOperationResult(NArchive::NExtract::NOperationResult::kOK));
  }
  return S_OK;
}

// This is Write function
HRESULT CCabFolderOutStream::Write2(const void *data, UInt32 size, UInt32 *processedSize, bool isOK)
{
  UInt32 realProcessed = 0;
  if (processedSize != NULL)
   *processedSize = 0;
  while(size != 0)
  {
    if (m_FileIsOpen)
    {
      UInt32 numBytesToWrite = (UInt32)MyMin(m_RemainFileSize, (UInt64)(size));
      HRESULT res = S_OK;
      if (numBytesToWrite > 0)
      {
        if (!isOK)
          m_IsOk = false;
        if (m_RealOutStream)
        {
          UInt32 processedSizeLocal = 0;
          res = m_RealOutStream->Write((const Byte *)data, numBytesToWrite, &processedSizeLocal);
          numBytesToWrite = processedSizeLocal;
        }
      }
      realProcessed += numBytesToWrite;
      if (processedSize != NULL)
        *processedSize = realProcessed;
      data = (const void *)((const Byte *)data + numBytesToWrite);
      size -= numBytesToWrite;
      m_RemainFileSize -= numBytesToWrite;
      m_PosInFolder += numBytesToWrite;
      if (res != S_OK)
        return res;
      if (m_RemainFileSize == 0)
      {
        m_RealOutStream.Release();
        RINOK(m_ExtractCallback->SetOperationResult(
          m_IsOk ? 
            NArchive::NExtract::NOperationResult::kOK:
            NArchive::NExtract::NOperationResult::kDataError));
        m_FileIsOpen = false;
      }
      if (realProcessed > 0)
        break; // with this break this function works as Write-Part
    }
    else
    {
      if (m_CurrentIndex >= m_ExtractStatuses->Size())
        return E_FAIL;

      const CMvItem &mvItem = m_Database->Items[m_StartIndex + m_CurrentIndex];
      const CItem &item = m_Database->Volumes[mvItem.VolumeIndex].Items[mvItem.ItemIndex];

      m_RemainFileSize = item.Size;

      UInt32 fileOffset = item.Offset;
      if (fileOffset < m_PosInFolder)
        return E_FAIL;
      if (fileOffset > m_PosInFolder)
      {
        UInt32 numBytesToWrite = (UInt32)MyMin((UInt64)fileOffset - m_PosInFolder, UInt64(size));
        realProcessed += numBytesToWrite;
        if (processedSize != NULL)
          *processedSize = realProcessed;
        data = (const void *)((const Byte *)data + numBytesToWrite);
        size -= numBytesToWrite;
        m_PosInFolder += numBytesToWrite;
      }
      if (fileOffset == m_PosInFolder)
      {
        RINOK(OpenFile());
        m_FileIsOpen = true;
        m_CurrentIndex++;
        m_IsOk = true;
      }
    }
  }
  return WriteEmptyFiles();
}

STDMETHODIMP CCabFolderOutStream::Write(const void *data, UInt32 size, UInt32 *processedSize)
{
  return Write2(data, size, processedSize, true);
}

HRESULT CCabFolderOutStream::FlushCorrupted()
{
  const UInt32 kBufferSize = (1 << 10);
  Byte buffer[kBufferSize];
  for (int i = 0; i < kBufferSize; i++)
    buffer[i] = 0;
  for (;;)
  {
    UInt64 remain = GetRemain();
    if (remain == 0)
      return S_OK;
    UInt32 size = (UInt32)MyMin(remain, (UInt64)kBufferSize);
    UInt32 processedSizeLocal = 0;
    RINOK(Write2(buffer, size, &processedSizeLocal, false));
  }
}

HRESULT CCabFolderOutStream::Unsupported()
{
  while(m_CurrentIndex < m_ExtractStatuses->Size())
  {
    HRESULT result = OpenFile();
    if (result != S_FALSE && result != S_OK)
      return result;
    m_RealOutStream.Release();
    RINOK(m_ExtractCallback->SetOperationResult(NArchive::NExtract::NOperationResult::kUnSupportedMethod));
    m_CurrentIndex++;
  }
  return S_OK;
}


STDMETHODIMP CHandler::Extract(const UInt32* indices, UInt32 numItems,
    Int32 _aTestMode, IArchiveExtractCallback *extractCallback)
{
  COM_TRY_BEGIN
  bool allFilesMode = (numItems == (UInt32)(-1));
  if (allFilesMode)
    numItems = m_Database.Items.Size();
  if(numItems == 0)
    return S_OK;
  bool testMode = (_aTestMode != 0);
  UInt64 totalUnPacked = 0;

  UInt32 i;
  int lastFolder = -2;
  UInt64 lastFolderSize = 0;
  for(i = 0; i < numItems; i++)
  {
    int index = allFilesMode ? i : indices[i];
    const CMvItem &mvItem = m_Database.Items[index];
    const CItem &item = m_Database.Volumes[mvItem.VolumeIndex].Items[mvItem.ItemIndex];
    if (item.IsDirectory())
      continue;
    int folderIndex = m_Database.GetFolderIndex(&mvItem);
    if (folderIndex != lastFolder)
      totalUnPacked += lastFolderSize;
    lastFolder = folderIndex;
    lastFolderSize = item.GetEndOffset();
  }
  totalUnPacked += lastFolderSize;

  extractCallback->SetTotal(totalUnPacked);

  totalUnPacked = 0;

  NCompress::CCopyCoder *copyCoderSpec = NULL;
  CMyComPtr<ICompressCoder> copyCoder;

  NCompress::NDeflate::NDecoder::CCOMCoder *deflateDecoderSpec = NULL;
  CMyComPtr<ICompressCoder> deflateDecoder;

  NCompress::NLzx::CDecoder *lzxDecoderSpec = NULL;
  CMyComPtr<ICompressCoder> lzxDecoder;

  NCompress::NQuantum::CDecoder *quantumDecoderSpec = NULL;
  CMyComPtr<ICompressCoder> quantumDecoder;

  CCabBlockInStream *cabBlockInStreamSpec = new CCabBlockInStream();
  CMyComPtr<ISequentialInStream> cabBlockInStream = cabBlockInStreamSpec;
  if (!cabBlockInStreamSpec->Create())
    return E_OUTOFMEMORY;

  CRecordVector<bool> extractStatuses;
  for(i = 0; i < numItems;)
  {
    int index = allFilesMode ? i : indices[i];

    const CMvItem &mvItem = m_Database.Items[index];
    const CDatabaseEx &db = m_Database.Volumes[mvItem.VolumeIndex];
    int itemIndex = mvItem.ItemIndex;
    const CItem &item = db.Items[itemIndex];

    i++;
    if (item.IsDirectory())
    {
      Int32 askMode= testMode ? 
          NArchive::NExtract::NAskMode::kTest :
          NArchive::NExtract::NAskMode::kExtract;
      CMyComPtr<ISequentialOutStream> realOutStream;
      RINOK(extractCallback->GetStream(index, &realOutStream, askMode));
      RINOK(extractCallback->PrepareOperation(askMode));
      realOutStream.Release();
      RINOK(extractCallback->SetOperationResult(NArchive::NExtract::NOperationResult::kOK));
      continue;
    }
    int folderIndex = m_Database.GetFolderIndex(&mvItem);
    if (folderIndex < 0)
    {
      // If we need previous archive
      Int32 askMode= testMode ? 
          NArchive::NExtract::NAskMode::kTest :
          NArchive::NExtract::NAskMode::kExtract;
      CMyComPtr<ISequentialOutStream> realOutStream;
      RINOK(extractCallback->GetStream(index, &realOutStream, askMode));
      RINOK(extractCallback->PrepareOperation(askMode));
      realOutStream.Release();
      RINOK(extractCallback->SetOperationResult(NArchive::NExtract::NOperationResult::kDataError));
      continue;
    }
    int startIndex2 = m_Database.FolderStartFileIndex[folderIndex];
    int startIndex = startIndex2;
    extractStatuses.Clear();
    for (; startIndex < index; startIndex++)
      extractStatuses.Add(false);
    extractStatuses.Add(true);
    startIndex++;
    UInt64 curUnpack = item.GetEndOffset();
    for(;i < numItems; i++)
    {
      int indexNext = allFilesMode ? i : indices[i];
      const CMvItem &mvItem = m_Database.Items[indexNext];
      const CItem &item = m_Database.Volumes[mvItem.VolumeIndex].Items[mvItem.ItemIndex];
      if (item.IsDirectory())
        continue;
      int newFolderIndex = m_Database.GetFolderIndex(&mvItem);

      if (newFolderIndex != folderIndex)
        break;
      for (; startIndex < indexNext; startIndex++)
        extractStatuses.Add(false);
      extractStatuses.Add(true);
      startIndex++;
      curUnpack = item.GetEndOffset();
    }

    RINOK(extractCallback->SetCompleted(&totalUnPacked));
    
    CCabFolderOutStream *cabFolderOutStream = new CCabFolderOutStream;
    CMyComPtr<ISequentialOutStream> outStream(cabFolderOutStream);

    const CFolder &folder = db.Folders[item.GetFolderIndex(db.Folders.Size())];

    cabFolderOutStream->Init(&m_Database, &extractStatuses, startIndex2, 
        curUnpack, extractCallback, testMode);

    cabBlockInStreamSpec->MsZip = false;
    switch(folder.GetCompressionMethod())
    {
      case NHeader::NCompressionMethodMajor::kNone:
        if(copyCoderSpec == NULL)
        {
          copyCoderSpec = new NCompress::CCopyCoder;
          copyCoder = copyCoderSpec;
        }
        break;
      case NHeader::NCompressionMethodMajor::kMSZip:
        if(deflateDecoderSpec == NULL)
        {
          deflateDecoderSpec = new NCompress::NDeflate::NDecoder::CCOMCoder;
          deflateDecoder = deflateDecoderSpec;
        }
        cabBlockInStreamSpec->MsZip = true;
        break;
      case NHeader::NCompressionMethodMajor::kLZX:
        if(lzxDecoderSpec == NULL)
        {
          lzxDecoderSpec = new NCompress::NLzx::CDecoder;
          lzxDecoder = lzxDecoderSpec;
        }
        RINOK(lzxDecoderSpec->SetParams(folder.CompressionTypeMinor));
        break;
      case NHeader::NCompressionMethodMajor::kQuantum:
        if(quantumDecoderSpec == NULL)
        {
          quantumDecoderSpec = new NCompress::NQuantum::CDecoder;
          quantumDecoder = quantumDecoderSpec;
        }
        quantumDecoderSpec->SetParams(folder.CompressionTypeMinor);
        break;
      default:
      {
        RINOK(cabFolderOutStream->Unsupported());
        totalUnPacked += curUnpack;
        continue;
      }
    }

    cabBlockInStreamSpec->InitForNewFolder();

    HRESULT res = S_OK;

    {
      int volIndex = mvItem.VolumeIndex;
      int locFolderIndex = item.GetFolderIndex(db.Folders.Size());
      bool keepHistory = false;
      bool keepInputBuffer = false;
      for (UInt32 f = 0; cabFolderOutStream->GetRemain() != 0;)
      {
        if (volIndex >= m_Database.Volumes.Size())
        {
          res = S_FALSE;
          break;
        }

        const CDatabaseEx &db = m_Database.Volumes[volIndex];
        const CFolder &folder = db.Folders[locFolderIndex];
        if (f == 0)
        {
          cabBlockInStreamSpec->SetStream(db.Stream);
          cabBlockInStreamSpec->ReservedSize = db.ArchiveInfo.GetDataBlockReserveSize();
          RINOK(db.Stream->Seek(db.StartPosition + folder.DataStart, STREAM_SEEK_SET, NULL));
        }
        if (f == folder.NumDataBlocks)
        {
          volIndex++;
          locFolderIndex = 0;
          f = 0;
          continue;
        }
        f++;

        cabBlockInStreamSpec->DataError = false;
        
        if (!keepInputBuffer)
          cabBlockInStreamSpec->InitForNewBlock();

        UInt32 packSize, unpackSize;
        res = cabBlockInStreamSpec->PreRead(packSize, unpackSize);
        if (res == S_FALSE)
          break;
        RINOK(res);
        keepInputBuffer = (unpackSize == 0);
        if (keepInputBuffer)
          continue;


        UInt64 totalUnPacked2 = totalUnPacked + cabFolderOutStream->GetPosInFolder();
        RINOK(extractCallback->SetCompleted(&totalUnPacked2));
        UInt64 unpackRemain = cabFolderOutStream->GetRemain();

        const UInt32 kBlockSizeMax = (1 << 15);
        if (unpackRemain > kBlockSizeMax)
          unpackRemain = kBlockSizeMax;
        if (unpackRemain > unpackSize)
          unpackRemain  = unpackSize;
   
        switch(folder.GetCompressionMethod())
        {
          case NHeader::NCompressionMethodMajor::kNone:
            res = copyCoder->Code(cabBlockInStream, outStream, NULL, &unpackRemain, NULL);
            break;
          case NHeader::NCompressionMethodMajor::kMSZip:
            deflateDecoderSpec->SetKeepHistory(keepHistory);
            res = deflateDecoder->Code(cabBlockInStream, outStream, NULL, &unpackRemain, NULL);
            break;
          case NHeader::NCompressionMethodMajor::kLZX:
            lzxDecoderSpec->SetKeepHistory(keepHistory, cabBlockInStreamSpec->GetAlign());
            res = lzxDecoder->Code(cabBlockInStream, outStream, NULL, &unpackRemain, NULL);
            break;
          case NHeader::NCompressionMethodMajor::kQuantum:
            quantumDecoderSpec->SetKeepHistory(keepHistory);
            res = quantumDecoder->Code(cabBlockInStream, outStream, NULL, &unpackRemain, NULL);
          break;
        }
        if (res != S_OK)
        {
          if (res != S_FALSE)
            RINOK(res);
          break;
        }
        keepHistory = true;
      }
      if (res == S_OK)
      {
        RINOK(cabFolderOutStream->WriteEmptyFiles());
      }
    }
    if (res != S_OK || cabFolderOutStream->GetRemain() != 0)
    {
      RINOK(cabFolderOutStream->FlushCorrupted());
    }
    totalUnPacked += curUnpack;
  }
  return S_OK;
  COM_TRY_END
}

STDMETHODIMP CHandler::GetNumberOfItems(UInt32 *numItems)
{
  *numItems = m_Database.Items.Size();
  return S_OK;
}

}}