Add span-based byte buffer ToString helper

Author: TheNathannator

Program/PacketParsing/Backends/PcapBackend.cs

@@ -128,7 +128,7 @@ private static unsafe void OnPacketArrival(object sender, PacketCapture packet)
             if (LogPackets)
             {
                 string packetLogString = $"{packet.Header.Timeval.Date:yyyy-MM-dd hh:mm:ss.fff} [{packet.Data.Length}] " +
-                    $"{BitConverter.ToString(headerData.ToArray())} | {BitConverter.ToString(packetData.ToArray())}";
+                    $"{ParsingUtils.ToString(headerData)} | {ParsingUtils.ToString(packetData)}";
                 Console.WriteLine(packetLogString);
                 Logging.Packet_WriteLine(packetLogString);
             }

Program/PacketParsing/ParsingUtils.cs

@@ -33,7 +33,7 @@ public static bool DecodeLEB128(ReadOnlySpan<byte> data, out int result, out int
             // Detect length sequences longer than 4 bytes
             if ((value & 0x80) != 0)
             {
-                Debug.WriteLine($"Variable-length value is greater than 4 bytes! Buffer: {BitConverter.ToString(data.ToArray())}");
+                Debug.WriteLine($"Variable-length value is greater than 4 bytes! Buffer: {ToString(data)}");
                 byteLength = 0;
                 result = 0;
                 return false;
@@ -42,6 +42,28 @@ public static bool DecodeLEB128(ReadOnlySpan<byte> data, out int result, out int
             return true;
         }
 
+        public static string ToString(ReadOnlySpan<byte> buffer)
+        {
+            const string characters = "0123456789ABCDEF";
+
+            if (buffer.IsEmpty)
+                return "";
+
+            Span<char> stringBuffer = stackalloc char[buffer.Length * 3];
+            for (int i = 0; i < buffer.Length; i++)
+            {
+                byte value = buffer[i];
+                int stringIndex = i * 3;
+                stringBuffer[stringIndex] = characters[(value & 0xF0) >> 4];
+                stringBuffer[stringIndex + 1] = characters[value & 0x0F];
+                stringBuffer[stringIndex + 2] = '-';
+            }
+            // Exclude last '-'
+            stringBuffer = stringBuffer.Slice(0, stringBuffer.Length - 1);
+
+            return stringBuffer.ToString();
+        }
+
         /// <summary>
         /// Scales a byte to a short, starting from the negative end.
         /// </summary>