public void WriteBitmap(Bitmap b)
{
if (disposed)
{
throw new ObjectDisposedException(GetType().FullName);
}
if (b.Width != Width)
{
throw new ArgumentException(String.Format("The width of the supplied bitmap ({0}) must match the width of the output png ({1}).", b.Width, Width));
}
BitmapData bData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb);
byte[] data = new byte[b.Width * b.Height * 4];
Marshal.Copy(bData.Scan0, data, 0, data.Length);
b.UnlockBits(bData);
if (dstream == null)
{
dstream = new DataStream();
}
if (zstream == null)
{
zstream = new ZlibStream(dstream, CompressionMode.Compress);
}
byte[] filterType = new byte[] { 0 }; //none
byte[] pixel = new byte[4];
int lineWidth = b.Width * 4;
for (int y = 0; y < b.Height; y++)
{
zstream.Write(filterType, 0, 1);
for (int x = 0; x < b.Width; x++)
{
int offset = y * lineWidth + x * 4;
//needs to be rgba
if (BitConverter.IsLittleEndian)
{
pixel[2] = data[offset]; //b
pixel[1] = data[offset + 1]; //g
pixel[0] = data[offset + 2]; //r
pixel[3] = data[offset + 3]; //a
}
else
{
pixel[3] = data[offset]; //a
pixel[0] = data[offset + 1]; //r
pixel[1] = data[offset + 2]; //g
pixel[2] = data[offset + 3]; //b
}
zstream.Write(pixel, 0, 4);
}
}
zstream.Flush();
WriteChunk("IDAT", dstream.GetDataSoFar());
}
/// <summary>
/// Compresses the input buffer using Zlib
/// </summary>
/// <param name="decompressedData">Data to be compressed</param>
/// <returns>Zlib compressed buffer</returns>
public static byte[] CompressData(byte[] decompressedData)
{
// Create a new memory stream for the input dat.
using (MemoryStream input = new MemoryStream(decompressedData))
{
// Create a new memory stream for the output data.
using (var raw = new MemoryStream())
{
// Create the zlib compressor.
using (Stream compressor = new ZlibStream(raw, Ionic.Zlib.CompressionMode.Compress))
{
byte[] buffer = new byte[4096];
int n;
// Loop and compress all of the data in blocks.
while ((n = input.Read(buffer, 0, buffer.Length)) != 0)
{
compressor.Write(buffer, 0, n);
}
}
// Return the compressed data as a byte array.
return(raw.ToArray());
}
}
}
//streamは読み取り開始位置へSeek済みであること
public static byte[] ZlibDecompress(MemoryStream stream, int originalSize, int compressedSize)
{
#if false
byte[] data = new byte[compressedSize];
stream.Read(data, 0, data.Length);
return(ZlibStream.UncompressBuffer(data));
#else
byte[] decompressed = new byte[originalSize];
byte[] buf = new byte[4096];
int remain = compressedSize;
using (MemoryStream toStream = new MemoryStream(decompressed))
{
using (ZlibStream zlibStream = new ZlibStream(toStream, CompressionMode.Decompress))
{
while (remain > 0)
{
int count = (remain > buf.Length) ? buf.Length : remain;
stream.Read(buf, 0, count);
zlibStream.Write(buf, 0, count);
remain -= count;
}
}
}
return(decompressed);
#endif
}
/// <summary>
/// Decompresses buffer into stream.
/// </summary>
/// <param name="buffer"></param>
/// <param name="outStream"></param>
private void Decompress(byte[] buffer, Stream outStream)
{
using (var zlib = new ZlibStream(outStream, CompressionMode.Decompress))
{
zlib.Write(buffer, 0, buffer.Length);
}
}
public void Should_compress_and_decompress_using_supported_library()
{
var text = "Interoperability is so much fun!";
using var output = new MemoryStream();
using (var compressOutput = new ZlibStream(output, CompressionMode.Compress))
{
compressOutput.Write(Encoding.UTF8.GetBytes(text));
compressOutput.Flush();
}
output.Flush();
var bytes = output.ToArray();
using var input = new MemoryStream(bytes);
using var decompressStream = new InflaterInputStream(input);
var buffer = new byte[16384];
var length = decompressStream.Read(buffer, 0, buffer.Length);
var result = Encoding.UTF8.GetString(buffer, 0, length);
Assert.That(result, Is.EqualTo(text));
}
public void compressTextureFlags(int compFlag)
{
if (compFlag == 0)
{
//uncompressed
compressedData = (byte[])(uncompressedData.Clone());
}
else if (((CompressionTypesPackage)compFlag & CompressionTypesPackage.ZLIB) > 0)
{
try
{
var byteStream = new MemoryStream();
var outStream = new ZlibStream(byteStream, CompressionMode.Compress);
outStream.Write(uncompressedData, 0, uncompressedData.Length);
compressedData = byteStream.GetBuffer();
}
catch (Exception e)
{
logger.Error(e);
}
}
else if (((CompressionTypesPackage)compFlag & CompressionTypesPackage.LZX) > 0)
{
logger.Error("Found COMPRESS_LZX, unsupported!");
}
else if (((CompressionTypesPackage)compFlag & CompressionTypesPackage.LZO) > 0)
{
lock (lockObject)
{
compressedData = lzo.Compress(uncompressedData, false);
}
}
compressedSize = compressedData.Length;
}
public static void WriteZLIBFile(string fileName, CompoundTag tag, ByteOrder order = ByteOrder.Little)
{
using (NBTStream stream = new NBTStream(order))
{
tag.Write(stream);
int sum = 0;
using (MemoryStream ms = new MemoryStream())
{
ms.WriteByte(0x78);
ms.WriteByte(0x01);
using (ZlibStream zlib = new ZlibStream(ms, CompressionMode.Compress, true))
{
zlib.Write(stream.ToArray(), 0, (int)stream.Length);
sum = zlib.Checksum;
}
byte[] sumBytes = BitConverter.GetBytes(sum);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(sumBytes);
}
ms.Write(sumBytes, 0, sumBytes.Length);
File.WriteAllBytes(fileName, ms.ToArray());
}
}
}
public static byte[] Compress(this byte[] uncompressed, int level)
{
if (level == 0)
{
return(uncompressed);
}
byte[] result;
using (var ms = new MemoryStream())
{
using (var compressor =
new ZlibStream(ms, CompressionMode.Compress, CompressionLevel.Level0 + level))
compressor.Write(uncompressed, 0, uncompressed.Length);
result = ms.ToArray();
}
// If compression did not improve the situation, then use
// uncompressed bytes.
if (result.Length >= uncompressed.Length)
{
return(uncompressed);
}
return(result);
}
private void Encode_ZLIB()
{
MemoryStream bs = new MemoryStream();
bs.WriteByte(0x78);
WriteCompressionLevel(bs);
int sum = 0;
using (ZlibStream ds = new ZlibStream(bs, this.CompressionLevel, true))
{
ds.Write(this.Payload, 0, this.Payload.Length);
sum = ds.Checksum;
}
byte[] checksumBytes = BitConverter.GetBytes(sum);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(checksumBytes);
}
bs.Write(checksumBytes, 0, checksumBytes.Length);
this.Payload = bs.GetBuffer();
bs.Close();
}
public void GetData(Stream stream, BinaryReader reader, bool compressed = false)
{
reader.BaseStream.Seek(DataOffset + DataHeaderSize, SeekOrigin.Begin);
if (!DataCompressed || compressed)
{
for (var i = CompressedDataSize; i > 0; i -= Buffer.Length)
{
var size = i > Buffer.Length ? Buffer.Length : i;
reader.Read(Buffer, 0, size);
stream.Write(Buffer, 0, size);
}
}
else
{
using var zlibStream = new ZlibStream(stream, CompressionMode.Decompress);
for (var i = CompressedDataSize; i > 0; i -= Buffer.Length)
{
var size = i > Buffer.Length ? Buffer.Length : i;
reader.Read(Buffer, 0, size);
zlibStream.Write(Buffer, 0, size);
}
}
}
/// <summary>
/// Send an infocard update to the client using the dsace protocol.
/// </summary>
/// <param name="player"></param>
/// <param name="id"></param>
/// <param name="text"></param>
public static void SendInfocardUpdate(Player player, uint id, string text)
{
var isrc = new byte[0];
FLMsgType.AddUInt32(ref isrc, 0); // reset all cards flag
FLMsgType.AddUInt32(ref isrc, 1); // number of infocards
FLMsgType.AddUInt32(ref isrc, id); // id number
FLMsgType.AddUnicodeStringLen32(ref isrc, text); // unicode text array with size as uint
// Compress the infocard list
byte[] idest;
using (var ms = new MemoryStream())
{
using (var zs = new ZlibStream(ms, CompressionMode.Compress))
zs.Write(isrc, 0, isrc.Length);
idest = ms.ToArray();
}
// Pack the compressed infocards into the dsac command.
var command = new byte[0];
FLMsgType.AddUInt32(ref command, 0xD5AC);
FLMsgType.AddUInt32(ref command, 0x01);
FLMsgType.AddUInt32(ref command, (uint)idest.Length);
FLMsgType.AddUInt32(ref command, (uint)isrc.Length);
FLMsgType.AddArray(ref command, idest);
SendChat(player, command);
}
private static bool Compress(byte[] data, int max, out byte[] compressed)
{
compressed = null;
var level = CompressionLevel.Level4;
ReTry:
using (var tempMemoryStream = new MemoryStream())
{
using (var zipStream = new ZlibStream(tempMemoryStream, CompressionMode.Compress, level))
{
zipStream.Write(data, 0, data.Length);
}
compressed = tempMemoryStream.ToArray();
}
if (compressed.Length > max)
{
if (level == CompressionLevel.BestCompression)
{
return(false);
}
level = (CompressionLevel)(level + 1);
Debug.WriteLine(string.Format("- Retry {0}", level));
goto ReTry;
}
return(true);
}
/// <summary>
/// Compress data using GZip (the retunred buffer will be WITHOUT HEADER)
/// </summary>
/// <param name="dataToCompress">The stream that hold the data</param>
/// <returns>Bytes array of compressed data WITHOUT HEADER bytes</returns>
public static byte[] Compress(Stream dataToCompress)
{
/*using (var compressed = new MemoryStream())
* {
* using (var compressor = new System.IO.Compression.GZipStream(compressed,
* System.IO.Compression.CompressionMode.Compress))
* {
* dataToCompress.CopyTo(compressor);
* }
* // Get the compressed bytes only after closing the GZipStream
* return compressed.ToArray();
* }*/
using (var compressedOutput = new MemoryStream())
{
using (var compressedStream = new ZlibStream(compressedOutput,
Ionic.Zlib.CompressionMode.Compress,
CompressionLevel.Default, false))
{
var buffer = new byte[4096];
int byteCount;
do
{
byteCount = dataToCompress.Read(buffer, 0, buffer.Length);
if (byteCount > 0)
{
compressedStream.Write(buffer, 0, byteCount);
}
} while (byteCount > 0);
}
return(compressedOutput.ToArray());
}
}
public static byte[] DeCompress(byte[] raw)
{
byte[] result;
using (MemoryStream memoryStream = new MemoryStream())
{
using (ZlibStream zlibStream = new ZlibStream(memoryStream, Ionic.Zlib.CompressionMode.Decompress))
{
zlibStream.Write(raw, 0, raw.Length);
}
result = memoryStream.ToArray();
}
return(result);
/* public static byte[] DeCompress(byte[] raw)
* {
* byte[] result;
* using (MemoryStream memoryStream = new MemoryStream())
* {
* var a = new zlib.ZOutputStream(memoryStream);
* a.Write(raw, 0, raw.Length);
* result = memoryStream.ToArray();
* }
* return result;
* }*/
}
private void NextBlock()
{
MemoryStream compressed = new MemoryStream();
using (ZlibStream compStream = new ZlibStream(compressed, CompressionMode.Compress, true))
{
compStream.Write(_currentBlock, 0, _currentOffset);
}
byte[] writeData;
ushort writeLen;
if (compressed.Length < _currentOffset)
{
writeData = compressed.ToArray();
writeLen = (ushort)compressed.Length;
}
else
{
writeData = _currentBlock;
writeLen = (ushort)(_currentOffset | 0x8000);
}
byte[] header = new byte[2];
Utilities.WriteBytesLittleEndian(writeLen, header, 0);
_buffer.Write(header, 0, 2);
_buffer.Write(writeData, 0, writeLen & 0x7FFF);
++_currentBlockNum;
}
/// <summary>
/// Writes a block of file data, possibly compressing it.
/// </summary>
/// <param name="buffer">The data to write.</param>
/// <param name="offset">Offset of the first byte to write.</param>
/// <param name="count">The number of bytes to write.</param>
/// <returns>
/// The 'length' of the (possibly compressed) data written, including
/// a flag indicating compression (or not).
/// </returns>
private uint WriteDataBlock(byte[] buffer, int offset, int count)
{
MemoryStream compressed = new MemoryStream();
using (ZlibStream compStream = new ZlibStream(compressed, CompressionMode.Compress, true))
{
compStream.Write(buffer, offset, count);
}
byte[] writeData;
int writeOffset;
int writeLen;
if (compressed.Length < count)
{
writeData = compressed.ToArray();
writeOffset = 0;
writeLen = (int)compressed.Length;
}
else
{
writeData = buffer;
writeOffset = offset;
writeLen = count | 0x01000000;
}
_context.RawStream.Write(writeData, writeOffset, writeLen & 0xFFFFFF);
return((uint)writeLen);
}
/// <summary>
/// Compresses a byte array using the specified compression type.
/// </summary>
/// <param name="bytes">The byte array to be compressed.</param>
/// <param name="level">Amount of compression to use.</param>
/// <param name="type">Type of compression to use.</param>
/// <returns>Compressed byte array.</returns>
public static byte[] Compress(this byte[] bytes, CompressionLevel level, CompressionType type)
{
using (MemoryStream memory = new MemoryStream())
{
switch (type)
{
case CompressionType.Zlib:
using (ZlibStream stream = new ZlibStream(memory, CompressionMode.Compress, level, true))
stream.Write(bytes, 0, bytes.Length);
break;
case CompressionType.GZip:
using (GZipStream stream = new GZipStream(memory, CompressionMode.Compress, level, true))
stream.Write(bytes, 0, bytes.Length);
break;
default:
throw new ArgumentException("Unknown compression type.");
}
memory.Position = 0;
bytes = new byte[memory.Length];
memory.Read(bytes, 0, (int)memory.Length);
}
return(bytes);
}
/// <summary>
/// 解凍
/// </summary>
public byte[] Inflate(int contentIndex)
{
int offset = SZipHeader.Size
+ _header.CompressedContentHeaderTableSize
+ _header.CompressedContentNameTableSize;
for (int i = 0; i < contentIndex; i++)
{
offset += _contents[i].CompressedDataSize;
}
_stream.Seek(offset, SeekOrigin.Begin);
byte[] buf = new byte[4 * 1024];
byte[] uncompressed = new byte[_contents[contentIndex].OriginalDataSize];
int remain = _contents[contentIndex].CompressedDataSize;
using (MemoryStream toStram = new MemoryStream(uncompressed))
{
using (ZlibStream zlibStream = new ZlibStream(toStram, CompressionMode.Decompress))
{
while (remain > 0)
{
int count = (remain > buf.Length) ? buf.Length : remain;
_stream.Read(buf, 0, count);
zlibStream.Write(buf, 0, count);
remain -= count;
}
}
}
return(uncompressed);
}
public void TestInvalidChecksum()
{
byte[] testData = Encoding.ASCII.GetBytes("This is a test string");
MemoryStream compressedStream = new MemoryStream();
using (ZlibStream zs = new ZlibStream(compressedStream, CompressionMode.Compress, true))
{
zs.Write(testData, 0, testData.Length);
}
compressedStream.Seek(-2, SeekOrigin.End);
compressedStream.Write(new byte[] { 0, 0 }, 0, 2);
compressedStream.Position = 0;
Assert.Throws <InvalidDataException>(() =>
{
using (ZlibStream uzs = new ZlibStream(compressedStream, CompressionMode.Decompress, true))
{
byte[] outData = new byte[testData.Length];
uzs.Read(outData, 0, outData.Length);
Assert.Equal(testData, outData);
// Should be end of stream
Assert.Equal(-1, uzs.ReadByte());
}
});
}
private static void Unzip(byte[] compressed, int start, int count)
{
using (ZlibStream deCompressor = new ZlibStream(unzipOut, CompressionMode.Decompress, CompressionLevel.Default, true))
{
deCompressor.Write(compressed, start, count);
}
}
private static void Zip(byte[] buffer, int start, int count)
{
using (ZlibStream compressor = new ZlibStream(zipOut, CompressionMode.Compress, CompressionLevel.Default, true))
{
compressor.Write(buffer, start, count);
}
}
/// <summary>
/// Compress the contents of the provided array
/// </summary>
/// <param name="data">An uncompressed byte array</param>
/// <returns></returns>
public static byte[] Compress(byte[] data)
{
using (MemoryStream out1 = new MemoryStream())
{
ZlibStream deflaterOutputStream = new ZlibStream(out1, CompressionMode.Compress);
try
{
//for (int i = 0; i < data.Length; i++)
//deflaterOutputStream.WriteByte(data[i]);
deflaterOutputStream.Write(data, 0, data.Length); //Tony Qu changed the code
return(out1.ToArray());
}
catch (IOException e)
{
throw new RecordFormatException(e.ToString());
}
finally
{
out1.Close();
if (deflaterOutputStream != null)
{
deflaterOutputStream.Close();
}
}
}
}
private static byte[] Compress(Hash hash, byte[] data)
{
byte[] result = null;
using (var ms = new MemoryStream())
using (var writer = new BinaryWriter(ms))
{
var sw = Stopwatch.StartNew();
using (var msCompress = new MemoryStream())
{
using (var zs = new ZlibStream(msCompress, CompressionMode.Compress, CompressionLevel.None))
{
zs.Write(data, 0, data.Length);
}
var compressed = msCompress.ToArray();
writer.Write(data.Length);
writer.Write(compressed);
result = ms.ToArray();
sw.Stop();
Debug.WriteLine(string.Format("Compression : {0:N0} -> {1:N0} - {2} ms ", data.Length, compressed.Length, sw.ElapsedMilliseconds));
}
}
DecryptionUtility.Decrypt(result, 0, result.Length, ref hash);
return(result);
}
private static byte[] Compress(byte[] data, int originalSize)
{
var level = CompressionLevel.Default;
ReTry:
using (var ms = new MemoryStream())
{
using (var stream = new ZlibStream(ms, CompressionMode.Compress, level))
{
stream.Write(data, 0, data.Length);
}
var compressed = ms.ToArray();
if (compressed.Length > originalSize)
{
if (level < CompressionLevel.BestCompression)
{
level = (level + 1);
goto ReTry;
}
else
{
return(null);
}
}
return(compressed);
}
}
public void Compress(string algorithm)
{
if (algorithm == CompressionAlgorithm.Deflate)
{
byte[] buffer = _memoryStream.ToArray();
MemoryStream ms = new MemoryStream();
DeflateStream deflateStream = new DeflateStream(ms, CompressionMode.Compress, true);
deflateStream.Write(buffer, 0, buffer.Length);
deflateStream.Close();
_memoryStream.Close();
_memoryStream = ms;
AMFReader amfReader = new AMFReader(_memoryStream);
AMFWriter amfWriter = new AMFWriter(_memoryStream);
_dataOutput = new DataOutput(amfWriter);
_dataInput = new DataInput(amfReader);
}
if (algorithm == CompressionAlgorithm.Zlib)
{
byte[] buffer = _memoryStream.ToArray();
MemoryStream ms = new MemoryStream();
ZlibStream zlibStream = new ZlibStream(ms, CompressionMode.Compress, true);
zlibStream.Write(buffer, 0, buffer.Length);
zlibStream.Flush();
zlibStream.Close();
zlibStream.Dispose();
_memoryStream.Close();
_memoryStream = ms;
AMFReader amfReader = new AMFReader(_memoryStream);
AMFWriter amfWriter = new AMFWriter(_memoryStream);
_dataOutput = new DataOutput(amfWriter);
_dataInput = new DataInput(amfReader);
}
}
// Public Methods (2)
//from: http://trac.opensubtitles.org/projects/opensubtitles/wiki/XMLRPC
//for gzip compression use function which adds no header to output,
//for PHP it is: base64_encode(gzencode($subfilecontents))
public static byte[] CompressZlib(byte[] rawBuffer)
{
using (var compressedOutput = new MemoryStream())
{
using (var rawStream = new MemoryStream(rawBuffer))
{
using (var compressedStream = new ZlibStream(compressedOutput,
Ionic.Zlib.CompressionMode.Compress,
CompressionLevel.Default, false))
{
var buffer = new byte[4096];
int byteCount;
do
{
byteCount = rawStream.Read(buffer, 0, buffer.Length);
if (byteCount > 0)
{
compressedStream.Write(buffer, 0, byteCount);
}
} while (byteCount > 0);
}
}
return(compressedOutput.ToArray());
}
}
public void SetChunkData(byte[] cData, Boolean isCompressed = true)
{
MemoryStream byteStream = new MemoryStream();
ZlibStream zStream = new ZlibStream(byteStream, CompressionMode.Decompress, CompressionLevel.BestCompression, true);
zStream.Write(cData, 0, cData.Length);
zStream.Flush();
zStream.Dispose();
zStream = null;
byte[] bytes = byteStream.ToArray();
byteStream.Dispose();
byteStream = null;
Block b;
WorldLocation blockLoc;
int x, y, z;
// Block Types
for (int i = 0; i < 32768; i++)
{
x = (Location.X * 16) + (i >> 11);
y = i & 0x7F;
z = (Location.Z * 16) + ((i & 0x780) >> 7);
blockLoc = new WorldLocation(x, y, z);
b = new Block((BlockType)bytes[i], blockLoc);
Blocks.Add(b);
}
// TODO: Read and handle block/sky light and metadata
bytes = null;
}
public CompressedData(IEnumerable <MatrixElement> elements)
{
_elements = elements;
// Get uncompressed data
byte[] uncompressed;
using (var memoryStream = new MemoryStream())
{
using (var binaryWriter = new BinaryWriter(memoryStream))
{
foreach (var element in _elements)
{
element.WriteToStream(binaryWriter);
}
binaryWriter.Flush();
memoryStream.Flush();
uncompressed = memoryStream.ToArray();
}
}
// Get compressed data
using (var memoryStream = new MemoryStream())
{
using (var compressor = new ZlibStream(memoryStream, CompressionMode.Compress, CompressionLevel.BestCompression))
{
compressor.Write(uncompressed, 0, uncompressed.Length);
}
_bytes = memoryStream.ToArray();
}
}
/// <summary>
/// 지정된 데이타를 압축한다.
/// </summary>
/// <param name="input">압축할 Data</param>
/// <returns>압축된 Data</returns>
public override byte[] Compress(byte[] input)
{
if (IsDebugEnabled)
{
log.Debug(CompressorTool.SR.CompressStartMsg);
}
// check input data
if (input.IsZeroLength())
{
if (IsDebugEnabled)
{
log.Debug(CompressorTool.SR.InvalidInputDataMsg);
}
return(CompressorTool.EmptyBytes);
}
byte[] output;
using (var outStream = new MemoryStream(input.Length)) {
using (var zlib = new ZlibStream(outStream, CompressionMode.Compress)) {
zlib.Write(input, 0, input.Length);
}
output = outStream.ToArray();
}
if (IsDebugEnabled)
{
log.Debug(CompressorTool.SR.CompressResultMsg, input.Length, output.Length, output.Length / (double)input.Length);
}
return(output);
}
public static byte[] WriteZLIBFile(CompoundTag tag, NBTEndian endian = NBTEndian.LITTLE_ENDIAN)
{
using (NBTStream stream = new NBTStream(endian))
{
tag.Write(stream);
int sum = 0;
using (MemoryStream ms = new MemoryStream())
{
ms.WriteByte(0x78);
ms.WriteByte(0x01);
using (ZlibStream zlib = new ZlibStream(ms, CompressionMode.Compress, true))
{
zlib.Write(stream.ToArray(), 0, (int)stream.Length);
sum = zlib.Checksum;
}
byte[] sumBytes = BitConverter.GetBytes(sum);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(sumBytes);
}
ms.Write(sumBytes, 0, sumBytes.Length);
return(ms.ToArray());
}
}
}
private void NextBlock()
{
MemoryStream compressed = new MemoryStream();
using (ZlibStream compStream = new ZlibStream(compressed, CompressionMode.Compress, true))
{
compStream.Write(_currentBlock, 0, _currentOffset);
}
byte[] writeData;
ushort writeLen;
if (compressed.Length < _currentOffset)
{
writeData = compressed.GetBuffer();
writeLen = (ushort)compressed.Length;
}
else
{
writeData = _currentBlock;
writeLen = (ushort)(_currentOffset | 0x8000);
}
byte[] header = new byte[2];
Utilities.WriteBytesLittleEndian(writeLen, header, 0);
_buffer.Write(header, 0, 2);
_buffer.Write(writeData, 0, writeLen & 0x7FFF);
++_currentBlockNum;
}
/// <summary>
/// Writes a block of file data, possibly compressing it.
/// </summary>
/// <param name="buffer">The data to write</param>
/// <param name="offset">Offset of the first byte to write</param>
/// <param name="count">The number of bytes to write</param>
/// <returns>
/// The 'length' of the (possibly compressed) data written, including
/// a flag indicating compression (or not).
/// </returns>
private uint WriteDataBlock(byte[] buffer, int offset, int count)
{
MemoryStream compressed = new MemoryStream();
using (ZlibStream compStream = new ZlibStream(compressed, CompressionMode.Compress, true))
{
compStream.Write(buffer, offset, count);
}
byte[] writeData;
int writeOffset;
int writeLen;
if (compressed.Length < count)
{
writeData = compressed.GetBuffer();
writeOffset = 0;
writeLen = (int)compressed.Length;
}
else
{
writeData = buffer;
writeOffset = offset;
writeLen = count | 0x01000000;
}
_context.RawStream.Write(writeData, writeOffset, writeLen & 0xFFFFFF);
return (uint)writeLen;
}