public IndexEntry(byte[] bytes)
{
OriginalPosition = BitConverter.ToInt64(bytes, 0);
CompressedChunk = new ChunkDescriptor {
Position = BitConverter.ToInt64(bytes, CompressedChunkPositionOffset), Size = BitConverter.ToInt64(bytes, CompressedChunkSizeOffset)
};
}
public byte[] Read(ChunkDescriptor chunkDescriptor)
{
source.Seek(chunkDescriptor.Position, SeekOrigin.Begin);
var buffer = new byte[chunkDescriptor.Size];
source.Read(buffer, 0, buffer.Length);
return(buffer);
}
public static CompressedChunk FromSourceFile(string sourcePath, ChunkDescriptor descriptor)
{
var compressedChunk = new CompressedChunk {
SourceChunkDescriptor = descriptor
};
using (var reader = new CompressedChunkStreamReader(File.OpenRead(sourcePath)))
{
compressedChunk.data = reader.Read(descriptor);
}
return(compressedChunk);
}
public byte[] Read(ChunkDescriptor chunkDescriptor)
{
using (var targetStream = new MemoryStream())
{
using (var gzipStream = new GZipStream(targetStream, CompressionMode.Compress))
{
var reader = new ChunkStreamReader(source);
var chunk = reader.Read(chunkDescriptor);
gzipStream.Write(chunk, 0, chunk.Length);
}
return(targetStream.ToArray());
}
}
public ChunkDescriptor AppendToFile(string targetPath)
{
var position = File.Exists(targetPath) ? new FileInfo(targetPath).Length : 0;
var targetChunk = new ChunkDescriptor {
Position = position, Size = this.Length
};
using (FileStream outFile = new FileStream(targetPath, FileMode.Append, FileAccess.Write))
{
outFile.Write(data, 0, data.Length);
}
return(targetChunk);
}
public byte[] Read(ChunkDescriptor chunkDescriptor)
{
source.Seek(chunkDescriptor.Position, SeekOrigin.Begin);
var buffer = new byte[chunkDescriptor.Size];
source.Read(buffer, 0, buffer.Length);
using (var targetStream = new MemoryStream())
{
using (var gzipStream = new GZipStream(new MemoryStream(buffer), CompressionMode.Decompress))
{
gzipStream.CopyTo(targetStream);
}
return(targetStream.ToArray());
}
}
