private bool ReadCentralDirectoryStructure( BinaryReader br )
{
string fileName = "";
XUnzipFileInfo pFileInfo = new XUnzipFileInfo ();
SCentralDirectoryStructureHead head = new SCentralDirectoryStructureHead ();
head.versionMadeBy = br.ReadInt16 ();
head.versionNeededToExtract = br.ReadInt16 ();
head.generalPurposeBitFlag = new _UGeneralPurposeBitFlag ( br.ReadInt16 () );
head.compressionMethod = ( XUNZIP_COMPRESSION_METHOD ) br.ReadInt16 ();
head.dostime = br.ReadUInt32 ();
head.crc32 = br.ReadUInt32 ();
head.compressedSize = br.ReadUInt32 ();
head.uncompressedSize = br.ReadUInt32 ();
head.fileNameLength = br.ReadInt16 ();
head.extraFieldLength = br.ReadInt16 ();
head.fileCommentLength = br.ReadInt16 ();
head.diskNumberStart = br.ReadInt16 ();
head.internalFileAttributes = br.ReadInt16 ();
head.externalFileAttributes = br.ReadUInt32 ();
head.relativeOffsetOfLocalHeader = br.ReadUInt32 ();
if ( head.compressionMethod != XUNZIP_COMPRESSION_METHOD.METHOD_STORE &&
head.compressionMethod != XUNZIP_COMPRESSION_METHOD.METHOD_DEFLATE )
return false;
if ( head.generalPurposeBitFlag.bit0 != 0 )
return false;
if ( head.fileNameLength != 0 )
{
byte [] tmp = br.ReadBytes ( head.fileNameLength );
fileName = Encoding.UTF8.GetString ( tmp, 0, tmp.Length );
}
inputStream.Seek ( head.extraFieldLength, SeekOrigin.Current );
//inputStream.Seek ( head.extraFieldLength, SeekOrigin.Current );
inputStream.Seek ( head.fileCommentLength, SeekOrigin.Current );
if ( ( head.externalFileAttributes & 16 ) != 0 )
return true;
pFileInfo.fileName = fileName;
pFileInfo.compressedSize = ( int ) head.compressedSize;
pFileInfo.uncompressedSize = ( int ) head.uncompressedSize;
pFileInfo.crc32 = head.crc32;
pFileInfo.method = head.compressionMethod;
pFileInfo.encrypted = ( head.generalPurposeBitFlag.bit0 != 0 ) ? true : false;
pFileInfo.offsetLocalHeader = ( int ) head.relativeOffsetOfLocalHeader;
pFileInfo.offsetData = -1;
FileAddList ( pFileInfo );
return true;
}
private bool ReadLocalHeader( ref XUnzipFileInfo pFileInfo, BinaryReader br )
{
if ( ( ( SIGNATURE ) br.ReadUInt32 () ) != SIGNATURE.LOCAL_FILE_HEADER )
return false;
SLocalFileHeader head = new SLocalFileHeader ();
head.versionNeededToExtract = br.ReadInt16 ();
head.generalPurposeBitFlag = new _UGeneralPurposeBitFlag ( br.ReadInt16 () );
head.compressionMethod = ( XUNZIP_COMPRESSION_METHOD ) br.ReadInt16 ();
head.dostime = br.ReadUInt32 ();
head.crc32 = br.ReadUInt32 ();
head.compressedSize = br.ReadUInt32 ();
head.uncompressedSize = br.ReadUInt32 ();
head.fileNameLength = br.ReadInt16 ();
head.extraFieldLength = br.ReadInt16 ();
inputStream.Seek ( head.fileNameLength, SeekOrigin.Current );
inputStream.Seek ( head.extraFieldLength, SeekOrigin.Current );
pFileInfo.offsetData = ( int ) inputStream.Position;
return true;
}
private bool FileAddList( XUnzipFileInfo pFileInfo )
{
fileInfoList.Add ( pFileInfo );
return true;
}