/// <summary>
/// Compress a given array of bytes, storing the result within the 'out' variable 'compressedData'.
/// The compression is completed respected the settings provided.
/// </summary>
/// <param name="data">The data you want to compress using LZ4.</param>
/// <param name="compressedData">The compressed representation of the data, null if the result is not 'Success'.</param>
/// <param name="settings">The settings to use when compressing the provided data.</param>
/// <returns>An LZ4Result stating the result of the compression.</returns>
public static LZ4Result CompressBytes(byte[] data, out byte[] compressedData, LZ4CompressionSettings settings)
{
// Validate input arguments
if (data == null)
{
compressedData = null;
return(LZ4Result.UncompressedDataIsNull);
}
if (settings == null)
{
compressedData = null;
return(LZ4Result.CompressionSettingsAreNull);
}
// Validate the compression level
if (settings.CompressionLevel > LZ4CompressionLevel.Max ||
settings.CompressionLevel < LZ4CompressionLevel.Lowest)
{
compressedData = null;
return(LZ4Result.InvalidCompressionLevel);
}
// Attempt the compression
switch (settings.CompressionMode)
{
case LZ4CompressionMode.Fast:
{
if (settings.CompressionLevel != LZ4CompressionLevel.Default)
{
compressedData = null;
return(LZ4Result.FastCompressionOnlySupportsDefaultCompressionLevel);
}
compressedData = LZ4ManagedWrapper.LZ4Wrapper.CompressDefault(data);
if (compressedData.Length == 0)
{
compressedData = null;
return(LZ4Result.CompressionFailed);
}
break;
}
case LZ4CompressionMode.HighQuality:
{
compressedData = LZ4ManagedWrapper.LZ4Wrapper.CompressHighQuality(data, (int)settings.CompressionLevel);
if (compressedData.Length == 0)
{
compressedData = null;
return(LZ4Result.CompressionFailed);
}
break;
}
default:
{
compressedData = null;
return(LZ4Result.UnsupportedCompressionMode);
}
}
// We always return if an error occurred, so if we get here we have succeeded.
return(LZ4Result.Success);
}
/// <summary>
/// Compress a string, storing the result within the 'out' variable 'compressedData'.
/// The compression is completed respected the settings provided.
/// </summary>
/// <param name="data">The string you want to compress using LZ4.</param>
/// <param name="compressedData">The compressed representation of the data, null if the result is not 'Success'.</param>
/// <param name="settings">The settings to use when compressing the provided data.</param>
/// <returns>An LZ4Result stating the result of the compression.</returns>
public static LZ4Result CompressString(string data, out byte[] compressedData, LZ4CompressionSettings settings)
{
return(CompressBytes(Encoding.ASCII.GetBytes(data), out compressedData, settings));
}
/// <summary>
/// Compress a given stream, storing the result within the 'out' variable 'compressedData'.
/// The compression is completed respected the settings provided.
/// </summary>
/// <param name="stream">The stream you want to compress using LZ4.</param>
/// <param name="compressedData">The compressed representation of the data, null if the result is not 'Success'.</param>
/// <param name="settings">The settings to use when compressing the provided data.</param>
/// <returns>An LZ4Result stating the result of the compression.</returns>
public static LZ4Result CompressStream(Stream stream, out byte[] compressedData, LZ4CompressionSettings settings)
{
using (var tempStream = new MemoryStream())
{
stream.CopyTo(tempStream);
return(CompressBytes(tempStream.ToArray(), out compressedData, settings));
}
}
