static public void WriteBlockHeader(TrackingPipeWriter writer, NettraceType type)
{
/*
* [open tag]
* [nullreference tag]
* [type version]
* [minReader Version]
* [length of block name]
* [block name]
* [close tag]
*/
writer.WriteByte((byte)Tags.BeginPrivateObject);
writer.WriteByte((byte)Tags.NullReference);
writer.WriteInt(type.Version);
writer.WriteInt(type.MinimumReaderVersion);
if (type.Name == KnownTypeNames.EventBlock)
{
writer.WriteInt(KnownTypeNames.EventBlockCompressed.Length);
Encoding.UTF8.GetBytes(KnownTypeNames.EventBlockCompressed, writer);
}
else if (type.Name == KnownTypeNames.StackBlock)
{
writer.WriteInt(KnownTypeNames.StackBlockCompressed.Length);
Encoding.UTF8.GetBytes(KnownTypeNames.StackBlockCompressed, writer);
}
else
{
writer.WriteInt(type.Name.Length);
Encoding.UTF8.GetBytes(type.Name, writer);
}
writer.WriteByte((byte)Tags.EndObject);
}
private static void WriteBlockHeader(TrackingPipeWriter writer, NettraceType type)
{
if (compress)
{
CompressBlockHelper.WriteBlockHeader(writer, type);
}
else if (decompress)
{
DecompressBlockHelper.WriteBlockHeader(writer, type);
}
else
{
/*
* [open tag]
* [nullreference tag]
* [type version]
* [minReader Version]
* [length of block name]
* [block name]
* [close tag]
*/
writer.WriteByte((byte)Tags.BeginPrivateObject);
writer.WriteByte((byte)Tags.NullReference);
writer.WriteInt(type.Version);
writer.WriteInt(type.MinimumReaderVersion);
writer.WriteInt(type.Name.Length);
Encoding.UTF8.GetBytes(type.Name, writer);
writer.WriteByte((byte)Tags.EndObject);
}
}
public static ValueTask <FlushResult> ProcessBlock(TrackingPipeWriter writer, NettraceBlock block, CancellationToken token)
{
// Write opening tag
writer.WriteByte((byte)Tags.BeginPrivateObject);
WriteBlockHeader(writer, block.Type);
var written = compress && CompressBlockHelper.WriteBlockAndPreamble(writer, block);
if (!written)
{
written = decompress && DecompressBlockHelper.WriteBlockAndPreamble(writer, block);
}
if (!written)
{
WriteBlockBodyPreamble(writer, block);
WriteBlockBody(writer, block.BlockBody);
}
// Write closing tag
writer.WriteByte((byte)Tags.EndObject);
return(writer.FlushAsync(token));
}
private static void WriteBlockBody(TrackingPipeWriter writer, ReadOnlySequence <byte> blockSequence)
{
foreach (var memory in blockSequence)
{
writer.Write(memory.Span);
}
}
public static int GetPadding(TrackingPipeWriter writer, NettraceBlock block)
{
// Get padding size
var offset = (writer.WrittenCount + sizeof(int)) % 4;
var padding = (int)((4 - offset) % 4);
return(padding);
}
public static void WriteInitialFileContext(TrackingPipeWriter writer)
{
// Write Preamble
Encoding.UTF8.GetBytes("Nettrace", writer);
// Write StreamHeader
writer.WriteInt(20);
Encoding.UTF8.GetBytes("!FastSerialization.1", writer);
}
private static void WriteBlockBodyPreamble(TrackingPipeWriter writer, NettraceBlock block)
{
if (block.Type.Name == KnownTypeNames.Trace)
{
return;
}
// padding should run before writing block size
var padding = GetPadding(writer, block);
// Write block size
writer.WriteInt(block.Size);
// Write padding
Span <byte> span = stackalloc byte[padding];
writer.Write(span);
}
public static bool WriteBlockAndPreamble(TrackingPipeWriter writer, NettraceBlock block)
{
if (block.Type.Name != KnownTypeNames.EventBlockCompressed && block.Type.Name != KnownTypeNames.StackBlockCompressed)
{
return(false);
}
var padding = BlockHelpers.GetPadding(writer, block);
var prefixLength = padding + sizeof(int);
using var decoder = new BrotliDecoder();
var source = ArrayPool <byte> .Shared.Rent((int)block.BlockBody.Length);
block.BlockBody.CopyTo(source);
var written = 0;
Memory <byte> memory;
try
{
var length = prefixLength + (int)block.BlockBody.Length;
memory = writer.GetMemory(length);
while (!BrotliDecoder.TryDecompress(source.AsSpan(0, (int)block.BlockBody.Length), memory.Slice(prefixLength).Span, out written))
{
length = memory.Length * 2;
memory = writer.GetMemory(length);
}
}
finally
{
ArrayPool <byte> .Shared.Return(source);
}
// Write size
BitConverter.TryWriteBytes(memory.Span, written);
// clear padding bits
memory.Slice(sizeof(int), padding).Span.Clear();
writer.Advance(written + prefixLength);
return(true);
}
public static bool WriteBlockAndPreamble(TrackingPipeWriter writer, NettraceBlock block)
{
if (block.Type.Name != KnownTypeNames.EventBlock && block.Type.Name != KnownTypeNames.StackBlock)
{
return(false);
}
var blockSequence = block.BlockBody;
var maxLength = BrotliEncoder.GetMaxCompressedLength((int)blockSequence.Length);
var padding = BlockHelpers.GetPadding(writer !, block);
var prefixLength = padding + sizeof(int);
var memory = writer !.GetMemory(maxLength + prefixLength);
// clear padding bits
memory.Slice(0, prefixLength).Span.Clear();
using var encoder = new BrotliEncoder(quality: 9, window: 10);
var slicedMemory = memory.Slice(prefixLength);
var totalWritten = 0;
OperationStatus status;
foreach (var sequence in blockSequence)
{
status = encoder.Compress(sequence.Span, slicedMemory.Span, out var consumed, out var written, false);
Debug.Assert(consumed == sequence.Span.Length);
Debug.Assert(status == OperationStatus.Done);
slicedMemory = slicedMemory.Slice(written);
totalWritten += written;
}
status = encoder.Compress(ReadOnlySpan <byte> .Empty, slicedMemory.Span, out var _, out var written2, true);
Debug.Assert(status == OperationStatus.Done);
totalWritten += written2;
// Write size
BitConverter.TryWriteBytes(memory.Span, totalWritten);
writer.Advance(totalWritten + prefixLength);
return(true);
}
