private static void ExtractFile(string f, LzmaDecoder decoder)
{
using (var input = File.OpenRead(f)) {
long uncompressedLength = Lzma.PrepareDecoder(decoder, input);
using (var output = File.OpenWrite(f.Remove(f.Length - 5)))
decoder.Code(input, output, input.Length, uncompressedLength, null);
}
}
public static long PrepareDecoder(LzmaDecoder decoder, Stream source)
{
byte[] properties = new byte[5];
source.Read(properties, 0, 5);
decoder.SetDecoderProperties(properties);
byte[] uncompressedSize = new byte[sizeof(Int64)];
source.Read(uncompressedSize, 0, sizeof(Int64));
return BitConverter.ToInt64(uncompressedSize, 0);
}
public static void Pack(string directory, string filename)
{
List<FileInfo> infos = new List<FileInfo>();
LzmaDecoder decoder = new LzmaDecoder();
// Figure out the info for each file we need to compress.
foreach (string fn in Directory.GetFiles(directory, "*.lzma")) {
// Remove the extension.
infos.Add(new FileInfo(fn));
}
string tempFilename = Path.GetTempFileName();
using (var output = File.OpenWrite(filename)) {
// First pass: write file table to output, and combine files.
//
// File table format:
// <number entries>
// file1: <name> <lzma size> <uncompressed size>
// file2: <name> <lzma size> <uncompressed size>
// ......
// filen: <name> <lzma size> <uncompressed size>
using (BinaryWriter writer = new BinaryWriter(output)) {
writer.Write(infos.Count);
using (var tempFile = File.OpenWrite(tempFilename))
foreach (FileInfo fi in infos) {
writer.Write(fi.Name);
writer.Write(fi.Length);
// Decompress this file to the temp blob.
using (var thisFile = fi.OpenRead()) {
long uncompressedSize = PrepareDecoder(decoder, thisFile);
decoder.Code(thisFile, tempFile, thisFile.Length, uncompressedSize, null);
writer.Write(uncompressedSize);
thisFile.Pipe(tempFile);
}
}
// Second pass: write LZMA header to output, and compress the temp blob
// into the output file.
LzmaEncoder encoder = new LzmaEncoder();
using (var tempFile = File.OpenRead(tempFilename)) {
WriteHeader(encoder, tempFile, output);
encoder.Code(tempFile, output, -1, -1, null);
}
}
}
}
private static void TryExtract(string directory)
{
if (Directory.Exists(directory)) {
LzmaDecoder decoder = new LzmaDecoder();
ProcessDirectory(directory, fn => ExtractFile(fn, decoder));
}
}
public static void Unpack(string filename, string directory)
{
List<ExtendedFileInfo> infos = new List<ExtendedFileInfo>();
string tempFilename = Path.GetTempFileName();
using (var archive = File.OpenRead(filename)) {
using (BinaryReader reader = new BinaryReader(archive)) {
int count = reader.ReadInt32();
for (int i = 0; i < count; i++) {
string name = reader.ReadString();
long csize = reader.ReadInt64();
long ucsize = reader.ReadInt64();
infos.Add(new ExtendedFileInfo(new FileInfo(Path.Combine(directory,name)), csize, ucsize));
}
// Unpack the compressed blob.
using (var tempFile = File.Open(tempFilename, FileMode.Create, FileAccess.ReadWrite)) {
LzmaDecoder decoder = new LzmaDecoder();
long uncompressedSize = PrepareDecoder(decoder, archive);
decoder.Code(archive, tempFile, archive.Length - archive.Position, uncompressedSize, null);
// Return to the beginning of the file.
tempFile.Seek(0, SeekOrigin.Begin);
// Split the compressed blob into individual files.
foreach (var efi in infos) {
using (var output = File.OpenWrite(efi.FileInfo.FullName.Remove(efi.FileInfo.FullName.Length - 5))) {
tempFile.Pipe(output, efi.UncompressedSize);
}
}
}
}
}
}
