public void FrameDroppingStreamDropsFramesWithStandardFrameFinder()
{
var data = new byte[] { 1, 2, 3, 4, 5, 6 };
var memoryStream = new MemoryStream();
memoryStream.Write(data, 0, data.Length);
memoryStream.Position = 0;
var rewindable = new RewindableBuilder(memoryStream).Build();
var frameFinderMock = new Mock<IFrameFinder>();
frameFinderMock.Setup(
frameFinder => frameFinder.ScanForCompleteFrames(rewindable.Stream)
).Returns(
() =>
{
var buffer = new byte[1];
int read;
int totalRead = 0;
List<FrameDescription> frames = new List<FrameDescription>();
do
{
read = rewindable.Stream.Read(buffer, 0, buffer.Length);
if (read > 0)
{
frames.Add(new FrameDescription() { RelativePosition = totalRead, FrameLength = read });
totalRead += read;
}
}
while (read > 0);
return new FrameSearchResult()
{
FinalRelativePosition = totalRead,
FramesFound = frames
};
}
);
var frameDroppingStream = new FrameDroppingStreamBuilder(rewindable, frameFinderMock.Object).Build();
var result = new byte[data.Length];
int resultRead = frameDroppingStream.Read(result, 0, result.Length);
Assert.IsTrue(result.Take(resultRead).SequenceEqual(data.Skip(data.Length - 1)));
}
public void IfNoFramesAvailableRetriesFromSamePosition()
{
var sourceStreamMock = new Mock<Stream>();
var data = new byte[] { 1, 2, 3, 4, 5, 6 };
int readCallCount = 0;
sourceStreamMock.Setup(sourceStream => sourceStream.Read(It.IsAny<byte[]>(), It.IsAny<int>(), It.IsAny<int>()))
.Returns((Func<byte[], int, int, int>)((buffer, offset, count) =>
{
int read = 0;
if (readCallCount < data.Length)
{
buffer[offset] = data[readCallCount];
read = 1;
}
readCallCount++;
return read;
}));
var rewindable = new RewindableBuilder(sourceStreamMock.Object).Build();
var frameFinderMock = new Mock<IFrameFinder>();
frameFinderMock.Setup(frameFinder => frameFinder.ScanForCompleteFrames(rewindable.Stream))
.Returns(
() =>
{
byte[] buffer = new byte[3];
int read = rewindable.Stream.Read(buffer, 0, buffer.Length);
var frameDescriptions = new List<FrameDescription>();
if (read == buffer.Length)
{
frameDescriptions.Add(new FrameDescription() { RelativePosition = -3, FrameLength = 3 });
}
return new FrameSearchResult() { FinalRelativePosition = 0, FramesFound = frameDescriptions };
}
);
var frameDroppingStream = new FrameDroppingStreamBuilder(rewindable, frameFinderMock.Object).Build();
var result = new byte[data.Length];
int totalResultRead = 0;
int resultRead;
int readAttempts = 0;
do
{
resultRead = frameDroppingStream.Read(result, totalResultRead, result.Length - totalResultRead);
totalResultRead += resultRead;
readAttempts++;
}
while (totalResultRead <= data.Length && readAttempts <= data.Length);
Assert.IsTrue(result.Take(totalResultRead).SequenceEqual(data));
}
public void FrameDroppingStreamPreservesOriginalStreamForFirstFrameOnlyFrameFinder()
{
var data = new byte[] { 1, 2, 3, 4, 5, 6 };
var memoryStream = new MemoryStream();
memoryStream.Write(data, 0, data.Length);
memoryStream.Position = 0;
var rewindable = new RewindableBuilder(memoryStream).Build();
var frameFinderMock = new Mock<IFrameFinder>();
frameFinderMock.Setup(
frameFinder => frameFinder.ScanForCompleteFrames(rewindable.Stream)
).Returns(
() =>
{
var buffer = new byte[1];
int read = rewindable.Stream.Read(buffer, 0, buffer.Length);
if (read > 0)
{
return new FrameSearchResult
{
FinalRelativePosition = read,
FramesFound = new [] { new FrameDescription() { RelativePosition = 0, FrameLength = read } }
};
}
return new FrameSearchResult();
}
);
var frameDroppingStream = new FrameDroppingStreamBuilder(rewindable, frameFinderMock.Object).Build();
var result = new byte[data.Length];
int resultRead = 0;
while (resultRead < data.Length)
{
resultRead += frameDroppingStream.Read(result, resultRead, result.Length - resultRead);
}
Assert.IsTrue(result.Take(resultRead).SequenceEqual(data));
}