diff --git a/LibGit/Extensions/StreamExtensions.cs b/LibGit/Extensions/StreamExtensions.cs
new file mode 100644
index 0000000..6555783
--- /dev/null
+++ b/LibGit/Extensions/StreamExtensions.cs
@@ -0,0 +1,211 @@
+using System.IO.Compression;
+
+namespace LibGit.Extensions;
+
+public static class StreamExtensions
+{
+ private const bool _debug = false;
+
+ public static long Remaining(this Stream stream)
+ {
+ //if (_debug) Console.WriteLine($"stream pos: {stream.Position}, stream len: {stream.Length}, stream rem: {stream.Length - stream.Position}");
+ return stream.Length - stream.Position;
+ }
+
+ public static int Peek(this Stream stream)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't peek a non-readable stream");
+ if (!stream.CanSeek)
+ throw new InvalidOperationException("Can't peek a non-seekable stream");
+
+ int peek = stream.ReadByte();
+ if (peek != -1)
+ stream.Seek(-1, SeekOrigin.Current);
+
+ return peek;
+ }
+
+ public static IEnumerable<byte> Peek(this Stream stream, long count)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't peek a non-readable stream");
+ if (!stream.CanSeek)
+ throw new InvalidOperationException("Can't peek a non-seekable stream");
+ long i;
+ for (i = 0; i < count; i++)
+ {
+ int peek = stream.ReadByte();
+ if (peek == -1)
+ {
+ if(_debug) Console.WriteLine($"Can't peek {count} bytes, only {i} bytes remaining");
+ stream.Seek(-i, SeekOrigin.Current);
+ yield break;
+ }
+
+ yield return (byte)peek;
+ }
+ stream.Seek(-i, SeekOrigin.Current);
+ }
+
+ public static IEnumerable<byte> ReadBytes(this Stream stream, long count)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+ if (!stream.CanSeek)
+ throw new InvalidOperationException("Can't read a non-seekable stream");
+
+ for (long i = 0; i < count; i++)
+ {
+ int read = stream.ReadByte();
+ if (read == -1)
+ yield break;
+ yield return (byte)read;
+ }
+ }
+
+ public static bool StartsWith(this Stream stream, IEnumerable<byte> sequence)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+ if (!stream.CanSeek)
+ throw new InvalidOperationException("Can't read a non-seekable stream");
+
+ if (_debug)
+ {
+ Console.WriteLine($"Expected: {sequence.AsHexString()} ({sequence.AsString()})");
+ Console.WriteLine($"Actual: {stream.Peek(sequence.Count()).AsHexString()} ({stream.Peek(sequence.Count()).AsString()})");
+ }
+
+ int readCount = 0;
+ foreach (int b in sequence)
+ {
+ int read = stream.ReadByte();
+ readCount++;
+ if (read == -1)
+ {
+ stream.Seek(-readCount, SeekOrigin.Current);
+ return false;
+ }
+
+ if (read != b)
+ {
+ if (_debug)
+ {
+ Console.ForegroundColor = ConsoleColor.Red;
+ Console.WriteLine("^^".PadLeft(readCount * 3 + 9));
+ Console.ResetColor();
+ }
+
+ stream.Seek(-readCount, SeekOrigin.Current);
+ return false;
+ }
+ }
+ stream.Seek(-readCount, SeekOrigin.Current);
+
+ return true;
+ }
+
+ public static bool StartsWith(this Stream stream, string ascii_seq)
+ {
+ return stream.StartsWith(ascii_seq.Select(x => (byte)x));
+ }
+
+ public static Stream Skip(this Stream stream, long count = 1)
+ {
+ if (!stream.CanSeek)
+ throw new InvalidOperationException("Can't skip a non-seekable stream");
+ stream.Seek(count, SeekOrigin.Current);
+ return stream;
+ }
+
+ public static IEnumerable<byte> ReadNullTerminatedField(this Stream stream, IEnumerable<byte>? binaryPrefix = null, string? asciiPrefix = null) => ReadTerminatedField(stream: stream, terminator: 0x00, binaryPrefix: binaryPrefix, asciiPrefix: asciiPrefix);
+ public static IEnumerable<byte> ReadSpaceTerminatedField(this Stream stream, IEnumerable<byte>? binaryPrefix = null, string? asciiPrefix = null) => ReadTerminatedField(stream: stream, terminator: 0x20, binaryPrefix: binaryPrefix, asciiPrefix: asciiPrefix);
+ public static IEnumerable<byte> ReadTerminatedField(this Stream stream, byte terminator, IEnumerable<byte>? binaryPrefix = null, string? asciiPrefix = null)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+ if (binaryPrefix != null)
+ if (!stream.StartsWith(binaryPrefix))
+ throw new InvalidDataException($"Binary prefix {stream.Peek(binaryPrefix.Count()).AsHexString()} does not match expected value of {binaryPrefix.AsHexString()}!");
+ else stream.Skip(binaryPrefix.Count());
+ else if (asciiPrefix != null)
+ if (!stream.StartsWith(asciiPrefix))
+ throw new InvalidDataException($"Text prefix {stream.Peek(asciiPrefix.Length).AsHexString()} ({stream.Peek(asciiPrefix.Length).AsString()}) does not match expected value of {asciiPrefix.AsBytes().AsHexString()} ({asciiPrefix})!");
+ else stream.Skip(asciiPrefix.Length);
+
+ var read = 0;
+ while (stream.Peek() != terminator)
+ {
+ if (_debug) Console.WriteLine($"ReadTerminatedField -- pos: {stream.Position}/+{stream.Remaining()}/{stream.Length} | next: {(char)stream.Peek()} | Length: {read}");
+ if (stream.Peek() == -1)
+ {
+ Console.WriteLine($"Warning: Reached end of stream while reading null-terminated field");
+ yield break;
+ }
+
+ read++;
+ yield return (byte)stream.ReadByte();
+ }
+
+ if (stream.Peek() == terminator) stream.Skip();
+ }
+
+ public static IEnumerable<byte> ReadToEnd(this Stream stream)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+
+ while (stream.Peek() != -1)
+ yield return (byte)stream.ReadByte();
+ }
+
+ public static int ReadInt32BE(this Stream stream)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+
+ var bytes = stream.ReadBytes(4).ToArray();
+
+ if (BitConverter.IsLittleEndian)
+ Array.Reverse(bytes);
+
+ Console.WriteLine("ReadInt32BE: " + bytes.AsHexString() + " => " + BitConverter.ToInt32(bytes));
+ return BitConverter.ToInt32(bytes);
+ }
+
+ //read variable length number
+ public static int ReadVLQ(this Stream stream)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+
+ int result = 0;
+ int shift = 0;
+ byte b;
+ do
+ {
+ b = (byte)stream.ReadByte();
+ result |= (b & 0b0111_1111) << shift;
+ shift += 7;
+ } while ((b & 0b1000_0000) != 0);
+
+ return result;
+ }
+ public static int ReadVLQBigEndian(this Stream stream)
+ {
+ if (!stream.CanRead)
+ throw new InvalidOperationException("Can't read a non-readable stream");
+
+ int result = 0;
+ int shift = 0;
+ byte b;
+ do
+ {
+ b = (byte)stream.ReadByte();
+ result = (result << 7) | (b & 0b0111_1111);
+ } while ((b & 0b1000_0000) != 0);
+
+ return result;
+ }
+}
\ No newline at end of file
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