public void Lz4_CompressDecompress()
{
// Start with a MemoryStream created from the sample data
using (MemoryStream source = new MemoryStream(s_sampledata))
{
using (MemoryStream dest = new MemoryStream())
{
// Compress the data into the destination memory stream instance
using (Lz4Writer compressor = new Lz4Writer(dest, CompressionLevel.Optimal, true)) source.CopyTo(compressor);
// The compressed data should be smaller than the source data
Assert.IsTrue(dest.Length < source.Length);
source.SetLength(0); // Clear the source stream
dest.Position = 0; // Reset the destination stream
// Decompress the data back into the source memory stream
using (Lz4Reader decompressor = new Lz4Reader(dest, true)) decompressor.CopyTo(source);
// Ensure that the original data has been restored
Assert.AreEqual(source.Length, s_sampledata.Length);
Assert.IsTrue(s_sampledata.SequenceEqual(source.ToArray()));
}
}
}
public void Lz4_Flush()
{
// Verify behavior of flushing a compression stream
using (MemoryStream compressed = new MemoryStream())
{
using (Lz4Writer stream = new Lz4Writer(compressed, true))
{
stream.Write(s_sampledata, 0, s_sampledata.Length);
// Get the unflushed length of the compressed stream and flush it
long unflushed = compressed.Length;
stream.Flush();
// The expectation is that the output stream will be longer after the flush
long flushedonce = compressed.Length;
Assert.IsTrue(compressed.Length > unflushed);
// Flushing the same data a second time should not have any impact at all
stream.Flush();
Assert.AreEqual(compressed.Length, flushedonce);
// The stream should still be writable after a flush operation
stream.Write(s_sampledata, 0, s_sampledata.Length / 10);
}
}
// Verify behavior of flushing a decompression stream
using (Lz4Reader stream = new Lz4Reader(new MemoryStream(s_sampledata)))
{
// Flush has no effect on decompression streams, just ensure it doesn't throw
stream.Flush();
}
}
public void Lz4_Seek()
{
// Verify behavior of a compression stream
using (Lz4Writer stream = new Lz4Writer(new MemoryStream()))
{
try { stream.Seek(50, SeekOrigin.Begin); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
try { stream.Seek(0, SeekOrigin.Current); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
try { stream.Seek(-50, SeekOrigin.End); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
// Verify behavior of a decompression stream
using (Lz4Reader stream = new Lz4Reader(new MemoryStream(s_sampledata)))
{
try { stream.Seek(50, SeekOrigin.Begin); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
try { stream.Seek(0, SeekOrigin.Current); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
try { stream.Seek(-50, SeekOrigin.End); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
public void Lz4_Read()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
using (MemoryStream compressed = new MemoryStream())
{
// Start with a compressed MemoryStream created from the sample data
using (Lz4Writer compressor = new Lz4Writer(compressed, CompressionLevel.Optimal, true))
{
try { compressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
}
// Check the constructor for ArgumentNullException while we're here
try { using (Lz4Reader decompressor = new Lz4Reader(null, false)) { }; Assert.Fail("Constructor should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
// Create a decompressor to test some of the error cases
using (Lz4Reader decompressor = new Lz4Reader(compressed, true))
{
// Send in some bum arguments to Read() to check they are caught
try { decompressor.Read(null, 0, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { decompressor.Read(buffer, -1, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { decompressor.Read(buffer, 0, -1); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { decompressor.Read(buffer, 0, buffer.Length + 1024); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentException)); }
// Attempting to read from the end of the compressed stream should throw an InvalidDataException
try { decompressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(InvalidDataException)); }
// Attempting to read from the middle of the compressed stream should throw an Lz4Exception
compressed.Position = compressed.Position / 2;
try { decompressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(Lz4Exception)); }
}
// Create a new decompressor against the same stream and make sure it doesn't throw
compressed.Position = 0;
using (Lz4Reader decompressor = new Lz4Reader(compressed, true))
{
// Reading zero bytes should not throw an exception
decompressor.Read(buffer, 0, 0);
while (decompressor.Read(buffer, 0, 8192) != 0)
{
}
}
}
}
public void Lz4_CanWrite()
{
// Verify behavior of a compression stream
using (Lz4Writer stream = new Lz4Writer(new MemoryStream()))
{
Assert.IsTrue(stream.CanWrite);
}
// Verify behavior of a decompression stream
using (Lz4Reader stream = new Lz4Reader(new MemoryStream(s_sampledata)))
{
Assert.IsFalse(stream.CanWrite);
}
}
public void Lz4_ReaderDispose()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
// Create a dummy stream and immediately dispose of it
Lz4Reader stream = new Lz4Reader(new MemoryStream(s_sampledata));
stream.Dispose();
// Test double dispose
stream.Dispose();
// All properties and methods should throw an ObjectDisposedException
try { var bs = stream.BaseStream; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanRead; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanSeek; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanWrite; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Flush(); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var l = stream.Length; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var l = stream.Position; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Position = 12345L; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Seek(0, SeekOrigin.Current); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.SetLength(12345L); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Write(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
}
public void Lz4_DecompressExternal()
{
// Decompress a stream created externally to this library
using (Lz4Reader reader = new Lz4Reader(Assembly.GetExecutingAssembly().GetManifestResourceStream("zuki.io.compression.test.thethreemusketeers.lz4")))
{
using (MemoryStream dest = new MemoryStream())
{
reader.CopyTo(dest);
dest.Flush();
// Verify that the output matches the sample data byte-for-byte
Assert.IsTrue(Enumerable.SequenceEqual(s_sampledata, dest.ToArray()));
}
}
}
public void Lz4_SetLength()
{
// Verify behavior of a compression stream
using (Lz4Writer stream = new Lz4Writer(new MemoryStream()))
{
try { stream.SetLength(12345L); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
// Verify behavior of a decompression stream
using (Lz4Reader stream = new Lz4Reader(new MemoryStream(s_sampledata)))
{
try { stream.SetLength(12345L); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
public void Lz4_BaseStream()
{
using (MemoryStream source = new MemoryStream())
{
using (Lz4Writer stream = new Lz4Writer(source, CompressionLevel.Optimal))
{
Assert.IsNotNull(stream.BaseStream);
Assert.AreSame(source, stream.BaseStream);
}
using (Lz4Reader stream = new Lz4Reader(source, true))
{
Assert.IsNotNull(stream.BaseStream);
Assert.AreSame(source, stream.BaseStream);
}
}
}
public void Lz4_Lz4Exception()
{
using (MemoryStream compressed = new MemoryStream())
{
// Start with a compressed MemoryStream created from the sample data
using (Lz4Writer compressor = new Lz4Writer(compressed, CompressionLevel.Optimal, true))
{
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
}
byte[] buffer = new byte[8192];
Lz4Exception thrown = null;
Lz4Exception deserialized = null;
// Create a decompressor to test exception cases
using (Lz4Reader decompressor = new Lz4Reader(compressed, true))
{
// Attempting to read from the middle of the compressed stream should throw a Lz4Exception
compressed.Position = compressed.Length / 2;
try { decompressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Lz4Exception ex) { thrown = ex; }
Assert.IsNotNull(thrown);
Assert.IsInstanceOfType(thrown, typeof(Lz4Exception));
// Check the error code property
Assert.AreEqual(-13, (int)thrown.ErrorCode); // ERROR_frameType_unknown (-13)
// Serialize and de-serialize the exception with a BinaryFormatter
BinaryFormatter formatter = new BinaryFormatter();
using (MemoryStream memstream = new MemoryStream())
{
formatter.Serialize(memstream, thrown);
memstream.Seek(0, 0);
deserialized = (Lz4Exception)formatter.Deserialize(memstream);
}
// Check that the exceptions are equivalent
Assert.AreEqual(thrown.ErrorCode, deserialized.ErrorCode);
Assert.AreEqual(thrown.StackTrace, deserialized.StackTrace);
Assert.AreEqual(thrown.ToString(), deserialized.ToString());
}
}
}
public void Lz4_Write()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
// Compress the sample data using a call to Write directly
using (MemoryStream compressed = new MemoryStream())
{
// Check the constructor for ArgumentNullException while we're here
try { using (Lz4Writer compressor = new Lz4Writer(null)) { }; Assert.Fail("Constructor should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
using (Lz4Writer compressor = new Lz4Writer(compressed, CompressionLevel.Optimal, true))
{
// Send in some bum arguments to Write() to check they are caught
try { compressor.Write(null); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { compressor.Write(null, 0, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { compressor.Write(s_sampledata, -1, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { compressor.Write(s_sampledata, 0, -1); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { compressor.Write(s_sampledata, 0, s_sampledata.Length + 1024); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentException)); }
// Not writing anything shouldn't throw an exception
compressor.Write(s_sampledata, 0, 0);
// Compress the data; there really isn't much that can go wrong with Write() itself
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
}
using (Lz4Reader reader = new Lz4Reader(compressed, true))
{
try { reader.Write(buffer, 0, buffer.Length); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
}
public void Lz4_Position()
{
// Start with a MemoryStream created from the sample data
using (MemoryStream source = new MemoryStream(s_sampledata))
{
using (MemoryStream dest = new MemoryStream())
{
// Test a compression stream
using (Lz4Writer compressor = new Lz4Writer(dest, CompressionLevel.Optimal, true))
{
// Lz4 streams do not report position
try { var pos = compressor.Position; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
// Attempting to set the position on the stream should throw
try { compressor.Position = 12345L; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
source.SetLength(0); // Clear the source stream
dest.Position = 0; // Reset the destination stream
// Test a decompression stream
using (Lz4Reader decompressor = new Lz4Reader(dest, true))
{
// Lz4 streams do not report position
try { var pos = decompressor.Position; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
// Attempting to set the position on the stream should throw
try { decompressor.Position = 12345L; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
}
}