private static void ReadPackInfo(StreamsInfo info, HeaderBuffer headerBytes)
{
info.PackPosition = headerBytes.ReadEncodedInt64();
int count = (int)headerBytes.ReadEncodedInt64();
info.PackedStreams = new PackedStreamInfo[count];
for (int i = 0; i < count; i++)
{
info.PackedStreams[i] = new PackedStreamInfo();
}
var prop = headerBytes.ReadProperty();
if (prop != HeaderProperty.kSize)
{
throw new InvalidFormatException("Expected Size Property");
}
for (int i = 0; i < count; i++)
{
info.PackedStreams[i].PackedSize = headerBytes.ReadEncodedInt64();
}
for (int i = 0; i < count; i++)
{
prop = headerBytes.ReadProperty();
if (prop != HeaderProperty.kCRC)
{
break;
}
info.PackedStreams[i].Crc = headerBytes.ReadEncodedInt64();
}
}
private StreamsInfo ReadPackedStreams(HeaderBuffer headerBytes)
{
StreamsInfo info = new StreamsInfo();
while (true)
{
var prop = headerBytes.ReadProperty();
switch (prop)
{
case HeaderProperty.kUnPackInfo:
{
ReadUnPackInfo(info, headerBytes);
}
break;
case HeaderProperty.kPackInfo:
{
ReadPackInfo(info, headerBytes);
}
break;
case HeaderProperty.kSubStreamsInfo:
{
ReadSubStreamsInfo(info, headerBytes);
}
break;
case HeaderProperty.kEnd:
return(info);
default:
throw new InvalidFormatException(prop.ToString());
}
}
}
private void ReadFileHeader(HeaderBuffer headerBytes)
{
while (true)
{
var prop = headerBytes.ReadProperty();
switch (prop)
{
case HeaderProperty.kMainStreamsInfo:
{
FilesInfo = ReadPackedStreams(headerBytes);
}
break;
case HeaderProperty.kFilesInfo:
{
Entries = ReadFilesInfo(FilesInfo, headerBytes);
}
break;
case HeaderProperty.kEnd:
return;
default:
throw new InvalidFormatException(prop.ToString());
}
}
}
private void Initialize()
{
if (!SignatureMatch(stream))
{
throw new InvalidFormatException("Not a 7Zip archive.");
}
BinaryReader reader = new BinaryReader(stream);
reader.ReadByte(); //major
reader.ReadByte(); //minor
uint crc = reader.ReadUInt32();
ulong nextHeaderOffset = reader.ReadUInt64();
ulong nextHeaderSize = reader.ReadUInt64();
uint nextHeaderCRC = reader.ReadUInt32();
BaseOffset = stream.Position;
if (crc == 0)
{
}
if (nextHeaderCRC == 0)
{
}
stream.Seek(BaseOffset + (long)nextHeaderOffset, SeekOrigin.Begin);
var headerBytes = new HeaderBuffer();
headerBytes.Bytes = reader.ReadBytes((int)nextHeaderSize);
ReadArchive(headerBytes);
PostProcess();
}
private void ReadUnPackInfo(StreamsInfo info, HeaderBuffer headerBytes)
{
var prop = headerBytes.ReadProperty();
int count = (int)headerBytes.ReadEncodedInt64();
info.Folders = new Folder[count];
if (headerBytes.ReadByte() != 0)
{
throw new NotSupportedException("External flag");
}
for (int i = 0; i < count; i++)
{
info.Folders[i] = ReadFolder(headerBytes);
}
prop = headerBytes.ReadProperty();
if (prop != HeaderProperty.kCodersUnPackSize)
{
throw new InvalidFormatException("Expected Size Property");
}
foreach (var folder in info.Folders)
{
int numOutStreams = folder.Coders.Aggregate(0, (sum, coder) => sum + (int)coder.NumberOfOutStreams);
folder.UnpackedStreamSizes = new ulong[numOutStreams];
for (uint j = 0; j < numOutStreams; j++)
{
folder.UnpackedStreamSizes[j] = headerBytes.ReadEncodedInt64();
}
}
prop = headerBytes.ReadProperty();
if (prop != HeaderProperty.kCRC)
{
return;
}
uint?[] crcs;
UnPackDigests(headerBytes, info.Folders.Length, out crcs);
for (int i = 0; i < info.Folders.Length; i++)
{
Folder folder = info.Folders[i];
folder.UnpackCRC = crcs[i];
}
prop = headerBytes.ReadProperty();
if (prop != HeaderProperty.kEnd)
{
throw new InvalidFormatException("Expected End property");
}
}
private static void UnPackDigests(HeaderBuffer headerBytes, int numItems, out uint?[] digests)
{
var digestsDefined = headerBytes.ReadBoolFlagsDefaultTrue(numItems);
digests = new uint?[numItems];
for (int i = 0; i < numItems; i++)
{
if (digestsDefined[i])
{
digests[i] = headerBytes.ReadUInt32();
}
}
}
private void ReadArchive(HeaderBuffer headerBytes)
{
while (true)
{
var prop = headerBytes.ReadProperty();
switch (prop)
{
case HeaderProperty.kEncodedHeader:
{
ArchiveInfo = ReadPackedStreams(headerBytes);
stream.Seek((long)ArchiveInfo.PackPosition + BaseOffset, SeekOrigin.Begin);
var firstFolder = ArchiveInfo.Folders.First();
ulong unpackSize = firstFolder.GetUnpackSize();
ulong packSize = ArchiveInfo.PackedStreams.Select(x => x.PackedSize)
.Aggregate((ulong)0, (sum, size) => sum + size);
byte[] unpackedBytes = new byte[(int)unpackSize];
Decoder decoder = new Decoder();
decoder.SetDecoderProperties(firstFolder.Coders[0].Properties);
using (MemoryStream outStream = new MemoryStream(unpackedBytes))
{
decoder.Code(stream, outStream, (long)(packSize), (long)unpackSize, null);
}
headerBytes = new HeaderBuffer {
Bytes = unpackedBytes
};
}
break;
case HeaderProperty.kHeader:
{
ReadFileHeader(headerBytes);
return;
}
default:
throw new NotSupportedException("7Zip header " + prop);
}
}
}
private Folder ReadFolder(HeaderBuffer headerBytes)
{
Folder folder = new Folder(this);
folder.Coders = headerBytes.CreateArray <CodersInfo>();
int numInStreams = 0;
int numOutStreams = 0;
foreach (var coder in folder.Coders)
{
byte mainByte = headerBytes.ReadByte();
int size = (byte)(mainByte & 0xF);
coder.Method = headerBytes.ReadBytes(size);
if ((mainByte & 0x10) != 0)
{
coder.NumberOfInStreams = headerBytes.ReadEncodedInt64();
coder.NumberOfOutStreams = headerBytes.ReadEncodedInt64();
}
else
{
coder.NumberOfInStreams = 1;
coder.NumberOfOutStreams = 1;
}
if ((mainByte & 0x20) != 0)
{
ulong propertiesSize = headerBytes.ReadEncodedInt64();
coder.Properties = headerBytes.ReadBytes((int)propertiesSize);
}
while ((mainByte & 0x80) != 0)
{
mainByte = headerBytes.ReadByte();
headerBytes.ReadBytes(mainByte & 0xF);
if ((mainByte & 0x10) != 0)
{
headerBytes.ReadEncodedInt64();
headerBytes.ReadEncodedInt64();
}
if ((mainByte & 0x20) != 0)
{
ulong propertiesSize = headerBytes.ReadEncodedInt64();
headerBytes.ReadBytes((int)propertiesSize);
}
}
numInStreams += (int)coder.NumberOfInStreams;
numOutStreams += (int)coder.NumberOfOutStreams;
}
int numBindPairs = numOutStreams - 1;
folder.BindPairs = new BindPair[numBindPairs];
for (int i = 0; i < numBindPairs; i++)
{
BindPair bindpair = new BindPair();
folder.BindPairs[i] = bindpair;
bindpair.InIndex = headerBytes.ReadEncodedInt64();
bindpair.OutIndex = headerBytes.ReadEncodedInt64();
}
int numPackedStreams = numInStreams - numBindPairs;
folder.PackedStreamIndices = new ulong[numPackedStreams];
if (numPackedStreams == 1)
{
uint pi = 0;
for (uint j = 0; j < numInStreams; j++)
{
if (!folder.BindPairs.Where(x => x.InIndex == j).Any())
{
folder.PackedStreamIndices[pi++] = j;
break;
}
}
}
else
{
for (uint i = 0; i < numPackedStreams; i++)
{
folder.PackedStreamIndices[i] = headerBytes.ReadEncodedInt64();
}
}
return(folder);
}
private static void ReadSubStreamsInfo(StreamsInfo info, HeaderBuffer headerBytes)
{
info.UnpackedStreams = new List <UnpackedStreamInfo>();
foreach (var folder in info.Folders)
{
folder.UnpackedStreams = new UnpackedStreamInfo[1];
folder.UnpackedStreams[0] = new UnpackedStreamInfo();
info.UnpackedStreams.Add(folder.UnpackedStreams[0]);
}
bool loop = true;
var prop = HeaderProperty.kEnd;
while (loop)
{
prop = headerBytes.ReadProperty();
switch (prop)
{
case HeaderProperty.kNumUnPackStream:
{
info.UnpackedStreams.Clear();
foreach (var folder in info.Folders)
{
var numStreams = (int)headerBytes.ReadEncodedInt64();
folder.UnpackedStreams = new UnpackedStreamInfo[numStreams];
folder.UnpackedStreams.Initialize(() => new UnpackedStreamInfo());
info.UnpackedStreams.AddRange(folder.UnpackedStreams);
}
}
break;
case HeaderProperty.kCRC:
case HeaderProperty.kSize:
case HeaderProperty.kEnd:
{
loop = false;
}
break;
default:
throw new InvalidFormatException(prop.ToString());
}
}
int si = 0;
for (int i = 0; i < info.Folders.Length; i++)
{
var folder = info.Folders[i];
ulong sum = 0;
if (folder.UnpackedStreams.Length == 0)
{
continue;
}
if (prop == HeaderProperty.kSize)
{
for (int j = 1; j < folder.UnpackedStreams.Length; j++)
{
ulong size = headerBytes.ReadEncodedInt64();
info.UnpackedStreams[si].UnpackedSize = size;
sum += size;
si++;
}
}
info.UnpackedStreams[si].UnpackedSize = folder.GetUnpackSize() - sum;
si++;
}
if (prop == HeaderProperty.kSize)
{
prop = headerBytes.ReadProperty();
}
int numDigests = 0;
foreach (var folder in info.Folders)
{
if (folder.UnpackedStreams.Length != 1 || !folder.UnpackCRC.HasValue)
{
numDigests += folder.UnpackedStreams.Length;
}
}
si = 0;
while (true)
{
if (prop == HeaderProperty.kCRC)
{
int digestIndex = 0;
uint?[] digests2;
UnPackDigests(headerBytes, numDigests, out digests2);
for (uint i = 0; i < info.Folders.Length; i++)
{
Folder folder = info.Folders[i];
if (folder.UnpackedStreams.Length == 1 && folder.UnpackCRC.HasValue)
{
info.UnpackedStreams[si].Digest = folder.UnpackCRC;
si++;
}
else
{
for (uint j = 0; j < folder.UnpackedStreams.Length; j++, digestIndex++)
{
info.UnpackedStreams[si].Digest = digests2[digestIndex];
si++;
}
}
}
}
else if (prop == HeaderProperty.kEnd)
{
return;
}
prop = headerBytes.ReadProperty();
}
}
private static HeaderEntry[] ReadFilesInfo(StreamsInfo info, HeaderBuffer headerBytes)
{
var entries = headerBytes.CreateArray <HeaderEntry>();
while (true)
{
var type = headerBytes.ReadProperty();
if (type == HeaderProperty.kEnd)
{
break;
}
var size = (int)headerBytes.ReadEncodedInt64();
switch (type)
{
case HeaderProperty.kName:
{
if (headerBytes.ReadByte() != 0)
{
throw new InvalidFormatException("Cannot be external");
}
entries.ForEach(f => f.Name = headerBytes.ReadName());
break;
}
case HeaderProperty.kEmptyStream:
{
info.EmptyStreamFlags = headerBytes.ReadBoolFlags(entries.Length);
break;
}
case HeaderProperty.kEmptyFile:
{
info.EmptyFileFlags = headerBytes.ReadBoolFlags(entries.Length);
break;
}
default:
{
headerBytes.ReadBytes(size);
break;
}
}
}
int emptyFileIndex = 0;
int sizeIndex = 0;
for (int i = 0; i < entries.Length; i++)
{
HeaderEntry file = entries[i];
file.IsAnti = false;
if (info.EmptyStreamFlags == null)
{
file.HasStream = true;
}
else
{
file.HasStream = !info.EmptyStreamFlags[i];
}
if (file.HasStream)
{
file.IsDirectory = false;
file.Size = info.UnpackedStreams[sizeIndex].UnpackedSize;
file.FileCRC = info.UnpackedStreams[sizeIndex].Digest;
sizeIndex++;
}
else
{
if (info.EmptyFileFlags == null)
{
file.IsDirectory = true;
}
else
{
file.IsDirectory = !info.EmptyFileFlags[emptyFileIndex];
}
emptyFileIndex++;
file.Size = 0;
}
}
return(entries);
}
