Misc tweaks (#111)

- Use System.HashCode in GetHashCode methods
- Update master key revisions.
- Remove some unneeded utility functions
- Suppress a spurious ReSharper warning

src/LibHac/Common/Id128.cs

@@ -44,10 +44,7 @@ namespace LibHac.Common
 
         public override int GetHashCode()
         {
-            unchecked
+            return HashCode.Combine(High, Low);
-            {
-                return (High.GetHashCode() * 397) ^ Low.GetHashCode();
-            }
         }
 
         public int CompareTo(Id128 other)

src/LibHac/Common/Key128.cs

@@ -36,10 +36,7 @@ namespace LibHac.Common
 
         public override int GetHashCode()
         {
-            int hashCode = -1653217991;
+            return HashCode.Combine(_dummy1, _dummy2);
-            hashCode = hashCode * -1521134295 + _dummy1.GetHashCode();
-            hashCode = hashCode * -1521134295 + _dummy2.GetHashCode();
-            return hashCode;
         }
 
         public static bool operator ==(Key128 left, Key128 right) => left.Equals(right);

src/LibHac/Fs/SaveDataStructs.cs

@@ -33,14 +33,7 @@ namespace LibHac.Fs
         public override int GetHashCode()
         {
             // ReSharper disable NonReadonlyMemberInGetHashCode
-            int hashCode = 487790375;
+            return HashCode.Combine(TitleId, Type, UserId, SaveDataId, Rank, Index);
-            hashCode = hashCode * -1521134295 + TitleId.GetHashCode();
-            hashCode = hashCode * -1521134295 + Type.GetHashCode();
-            hashCode = hashCode * -1521134295 + UserId.GetHashCode();
-            hashCode = hashCode * -1521134295 + SaveDataId.GetHashCode();
-            hashCode = hashCode * -1521134295 + Rank.GetHashCode();
-            hashCode = hashCode * -1521134295 + Index.GetHashCode();
-            return hashCode;
             // ReSharper restore NonReadonlyMemberInGetHashCode
         }
 

src/LibHac/Fs/Shim/Application.cs

@@ -35,6 +35,7 @@ namespace LibHac.Fs.Shim
 
             static Result Run(FileSystemClient fs, U8Span mountName, U8Span path)
             {
+                // ReSharper disable once VariableHidesOuterVariable
                 Result rc = MountHelpers.CheckMountName(mountName);
                 if (rc.IsFailure()) return rc;
 

src/LibHac/Ncm/ContentMetaKey.cs

@@ -50,16 +50,9 @@ namespace LibHac.Ncm
 
         public override int GetHashCode()
         {
-            unchecked
+            // ReSharper disable NonReadonlyMemberInGetHashCode
-            {
+            return HashCode.Combine(TitleId, Version, Type, Attributes);
-                // ReSharper disable NonReadonlyMemberInGetHashCode
+            // ReSharper restore NonReadonlyMemberInGetHashCode
-                int hashCode = TitleId.GetHashCode();
-                hashCode = (hashCode * 397) ^ (int)Version;
-                hashCode = (hashCode * 397) ^ Type.GetHashCode();
-                hashCode = (hashCode * 397) ^ Attributes.GetHashCode();
-                return hashCode;
-                // ReSharper restore NonReadonlyMemberInGetHashCode
-            }
         }
 
         public int CompareTo(ContentMetaKey other)

src/LibHac/Npdm/NpdmBinary.cs

@@ -1,5 +1,6 @@
 // ReSharper disable UnusedVariable
 using System;
+using System.Buffers.Binary;
 using System.IO;
 
 namespace LibHac.Npdm
@@ -53,10 +54,10 @@ namespace LibHac.Npdm
             reader.ReadInt32();
 
             //System resource size (max size as of 5.x: 534773760).
-            SystemResourceSize = Util.Swap32(reader.ReadInt32());
+            SystemResourceSize = BinaryPrimitives.ReverseEndianness(reader.ReadInt32());
 
             //ProcessCategory (0: regular title, 1: kernel built-in). Should be 0 here.
-            ProcessCategory = Util.Swap32(reader.ReadInt32());
+            ProcessCategory = BinaryPrimitives.ReverseEndianness(reader.ReadInt32());
 
             //Main entrypoint stack size.
             MainEntrypointStackSize = reader.ReadInt32();

src/LibHac/Util.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Numerics;
 using System.Runtime.CompilerServices;
@@ -471,7 +470,6 @@ namespace LibHac
 
         public static void MemDump(this StringBuilder sb, string prefix, byte[] data)
         {
-
             int max = 32;
             int remaining = data.Length;
             bool first = true;
@@ -501,21 +499,21 @@ namespace LibHac
             }
         }
 
-        public static string GetKeyRevisionSummary(int revision)
+        public static string GetKeyRevisionSummary(int revision) => revision switch
         {
-            switch (revision)
+            0 => "1.0.0-2.3.0",
-            {
+            1 => "3.0.0",
-                case 0: return "1.0.0-2.3.0";
+            2 => "3.0.1-3.0.2",
-                case 1: return "3.0.0";
+            3 => "4.0.0-4.1.0",
-                case 2: return "3.0.1-3.0.2";
+            4 => "5.0.0-5.1.0",
-                case 3: return "4.0.0-4.1.0";
+            5 => "6.0.0-6.0.1",
-                case 4: return "5.0.0-5.1.0";
+            6 => "6.2.0",
-                case 5: return "6.0.0-6.0.1";
+            7 => "7.0.0-8.0.1",
-                case 6: return "6.2.0";
+            8 => "8.1.0-8.1.1",
-                case 7: return "7.0.0-8.0.1";
+            9 => "9.0.0-9.0.1",
-                default: return "Unknown";
+            0xA => "9.1.0-",
-            }
+            _ => "Unknown"
-        }
+        };
 
         public static bool IsSubRange(long startIndex, long subLength, long length)
         {
@@ -523,16 +521,6 @@ namespace LibHac
             return !isOutOfRange;
         }
 
-        public static int Swap32(int value)
-        {
-            uint uintVal = (uint)value;
-
-            return (int)(((uintVal >> 24) & 0x000000ff) |
-                         ((uintVal >> 8) & 0x0000ff00) |
-                         ((uintVal << 8) & 0x00ff0000) |
-                         ((uintVal << 24) & 0xff000000));
-        }
-
         public static int GetMasterKeyRevision(int keyGeneration)
         {
             if (keyGeneration == 0) return 0;
@@ -540,44 +528,4 @@ namespace LibHac
             return keyGeneration - 1;
         }
     }
-
-    public class ByteArray128BitComparer : EqualityComparer<byte[]>
-    {
-        public override bool Equals(byte[] first, byte[] second)
-        {
-            if (first == null || second == null)
-            {
-                // null == null returns true.
-                // non-null == null returns false.
-                return first == second;
-            }
-            if (ReferenceEquals(first, second))
-            {
-                return true;
-            }
-            if (first.Length != second.Length)
-            {
-                return false;
-            }
-
-            return Util.ArraysEqual(first, second);
-        }
-
-        public override int GetHashCode(byte[] obj)
-        {
-            if (obj == null)
-            {
-                throw new ArgumentNullException(nameof(obj));
-            }
-            if (obj.Length != 16)
-            {
-                throw new ArgumentException("Length must be 16 bytes");
-            }
-
-            ulong hi = BitConverter.ToUInt64(obj, 0);
-            ulong lo = BitConverter.ToUInt64(obj, 8);
-
-            return (hi.GetHashCode() * 397) ^ lo.GetHashCode();
-        }
-    }
 }