more portable restructuring

MediaBrowser.Server.Startup.Common/Cryptography/BitConverterLE.cs

@@ -0,0 +1,239 @@
+//
+// Mono.Security.BitConverterLE.cs
+//  Like System.BitConverter but always little endian
+//
+// Author:
+//   Bernie Solomon
+//
+
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+// 
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+
+namespace Emby.Common.Implementations.Security
+{
+    internal sealed class BitConverterLE
+	{
+		private BitConverterLE ()
+		{
+		}
+
+		unsafe private static byte[] GetUShortBytes (byte *bytes)
+		{
+			if (BitConverter.IsLittleEndian)
+				return new byte [] { bytes [0], bytes [1] };
+			else
+				return new byte [] { bytes [1], bytes [0] };
+		}
+
+		unsafe private static byte[] GetUIntBytes (byte *bytes)
+		{
+			if (BitConverter.IsLittleEndian)
+				return new byte [] { bytes [0], bytes [1], bytes [2], bytes [3] };
+			else
+				return new byte [] { bytes [3], bytes [2], bytes [1], bytes [0] };
+		}
+
+		unsafe private static byte[] GetULongBytes (byte *bytes)
+		{
+			if (BitConverter.IsLittleEndian)
+				return new byte [] { bytes [0], bytes [1], bytes [2], bytes [3],
+						     bytes [4], bytes [5], bytes [6], bytes [7] };
+			else
+				return new byte [] { bytes [7], bytes [6], bytes [5], bytes [4],
+						     bytes [3], bytes [2], bytes [1], bytes [0] };
+		}
+
+		unsafe internal static byte[] GetBytes (bool value)
+		{
+			return new byte [] { value ? (byte)1 : (byte)0 };
+		}
+
+		unsafe internal static byte[] GetBytes (char value)
+		{
+			return GetUShortBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (short value)
+		{
+			return GetUShortBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (int value)
+		{
+			return GetUIntBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (long value)
+		{
+			return GetULongBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (ushort value)
+		{
+			return GetUShortBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (uint value)
+		{
+			return GetUIntBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (ulong value)
+		{
+			return GetULongBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (float value)
+		{
+			return GetUIntBytes ((byte *) &value);
+		}
+
+		unsafe internal static byte[] GetBytes (double value)
+		{
+			return GetULongBytes ((byte *) &value);
+		}
+
+		unsafe private static void UShortFromBytes (byte *dst, byte[] src, int startIndex)
+		{
+			if (BitConverter.IsLittleEndian) {
+				dst [0] = src [startIndex];
+				dst [1] = src [startIndex + 1];
+			} else {
+				dst [0] = src [startIndex + 1];
+				dst [1] = src [startIndex];
+			}
+		}
+
+		unsafe private static void UIntFromBytes (byte *dst, byte[] src, int startIndex)
+		{
+			if (BitConverter.IsLittleEndian) {
+				dst [0] = src [startIndex];
+				dst [1] = src [startIndex + 1];
+				dst [2] = src [startIndex + 2];
+				dst [3] = src [startIndex + 3];
+			} else {
+				dst [0] = src [startIndex + 3];
+				dst [1] = src [startIndex + 2];
+				dst [2] = src [startIndex + 1];
+				dst [3] = src [startIndex];
+			}
+		}
+
+		unsafe private static void ULongFromBytes (byte *dst, byte[] src, int startIndex)
+		{
+			if (BitConverter.IsLittleEndian) {
+				for (int i = 0; i < 8; ++i)
+					dst [i] = src [startIndex + i];
+			} else {
+				for (int i = 0; i < 8; ++i)
+					dst [i] = src [startIndex + (7 - i)];
+			}
+		}
+
+		unsafe internal static bool ToBoolean (byte[] value, int startIndex)
+		{
+			return value [startIndex] != 0;
+		}
+
+		unsafe internal static char ToChar (byte[] value, int startIndex)
+		{
+			char ret;
+
+			UShortFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static short ToInt16 (byte[] value, int startIndex)
+		{
+			short ret;
+
+			UShortFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static int ToInt32 (byte[] value, int startIndex)
+		{
+			int ret;
+
+			UIntFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static long ToInt64 (byte[] value, int startIndex)
+		{
+			long ret;
+
+			ULongFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static ushort ToUInt16 (byte[] value, int startIndex)
+		{
+			ushort ret;
+
+			UShortFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static uint ToUInt32 (byte[] value, int startIndex)
+		{
+			uint ret;
+
+			UIntFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static ulong ToUInt64 (byte[] value, int startIndex)
+		{
+			ulong ret;
+
+			ULongFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static float ToSingle (byte[] value, int startIndex)
+		{
+			float ret;
+
+			UIntFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+
+		unsafe internal static double ToDouble (byte[] value, int startIndex)
+		{
+			double ret;
+
+			ULongFromBytes ((byte *) &ret, value, startIndex);
+
+			return ret;
+		}
+	}
+}