diff options
Diffstat (limited to 'embeddable-dll-service/csharp/Ringlogger.cs')
-rw-r--r-- | embeddable-dll-service/csharp/Ringlogger.cs | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/embeddable-dll-service/csharp/Ringlogger.cs b/embeddable-dll-service/csharp/Ringlogger.cs new file mode 100644 index 00000000..711c22e7 --- /dev/null +++ b/embeddable-dll-service/csharp/Ringlogger.cs @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: MIT + * + * Copyright (C) 2019 WireGuard LLC. All Rights Reserved. + */ + +using System; +using System.IO; +using System.IO.MemoryMappedFiles; +using System.Text; + +namespace Tunnel +{ + public class Ringlogger + { + private readonly MemoryMappedViewAccessor _viewAccessor; + + public Ringlogger(string filename) + { + var file = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.ReadWrite | FileShare.Delete); + var mmap = MemoryMappedFile.CreateFromFile(file, null, 0, MemoryMappedFileAccess.Read, HandleInheritability.None, false); + _viewAccessor = mmap.CreateViewAccessor(0, 8 + 2048 * (512 + 8), MemoryMappedFileAccess.Read); + if (_viewAccessor.ReadUInt32(0) != 0xbadbabe) + throw new InvalidDataException("The provided file is missing the magic number."); + } + + public void WriteTo(TextWriter writer) + { + var start = _viewAccessor.ReadUInt32(4); + for (var i = 0; i < 2048; ++i) + { + var lineOffset = 8 + (8 + 512) * ((i + start) % 2048); + var timeNs = _viewAccessor.ReadInt64(lineOffset); + if (timeNs == 0) + continue; + var textBytes = new byte[512]; + _viewAccessor.ReadArray<byte>(lineOffset + 8, textBytes, 0, textBytes.Length); + var nullByte = Array.IndexOf<byte>(textBytes, 0); + if (nullByte <= 0) + continue; + var text = Encoding.UTF8.GetString(textBytes, 0, nullByte); + var time = DateTimeOffset.FromUnixTimeMilliseconds(timeNs / 1000000).ToString("yyyy'-'MM'-'dd HH':'mm':'ss'.'ffffff"); + writer.WriteLine(String.Format("{0}: {1}", time, text)); + } + } + } +} |