Update DirectoryPathParser, PathUtility and WindowsPath for 13.1.0

src/LibHac/Fs/Common/DirectoryPathParser.cs

@@ -3,8 +3,13 @@ using LibHac.Common;
 using LibHac.Diag;
 using static LibHac.Fs.StringTraits;
 
-namespace LibHac.Fs.Common;
+// ReSharper disable once CheckNamespace
+namespace LibHac.Fs;
 
+/// <summary>
+/// Iterates through each directory in a path beginning with the root directory.
+/// </summary>
+/// <remarks>Based on FS 13.1.0 (nnSdk 13.4.0)</remarks>
 [NonCopyableDisposable]
 public ref struct DirectoryPathParser
 {
@@ -15,11 +20,26 @@ public ref struct DirectoryPathParser
     // Todo: Make private so we can use the GetCurrentPath method once lifetime tracking is better
     public Path CurrentPath;
 
+    public DirectoryPathParser()
+    {
+        _buffer = Span<byte>.Empty;
+        _replacedChar = 0;
+        _position = 0;
+        CurrentPath = new Path();
+    }
+
     public void Dispose()
     {
         CurrentPath.Dispose();
     }
 
+    /// <summary>
+    /// Initializes this <see cref="DirectoryPathParser"/> with a new <see cref="Path"/>. The <see cref="Path"/>
+    /// should not be a fixed path that was just initialized with <see cref="PathFunctions.SetUpFixedPath"/>
+    /// because we need it to have an allocated write buffer.
+    /// </summary>
+    /// <param name="path">The <see cref="Path"/> to iterate. Must have an allocated write buffer.</param>
+    /// <returns>The <see cref="Result"/> of the operation.</returns>
     public Result Initialize(ref Path path)
     {
         Span<byte> pathBuffer = path.GetWriteBufferLength() != 0 ? path.GetWriteBuffer() : Span<byte>.Empty;

src/LibHac/Fs/Common/PathUtility.cs

@@ -1,6 +1,7 @@
 using System;
 using LibHac.Common;
 using LibHac.Diag;
+using LibHac.Fs.Impl;
 using LibHac.FsSrv.Sf;
 using LibHac.Util;
 using static LibHac.Fs.StringTraits;
@@ -11,7 +12,7 @@ namespace LibHac.Fs;
 /// <summary>
 /// Contains various utility functions for working with paths.
 /// </summary>
-/// <remarks>Based on FS 12.1.0 (nnSdk 12.3.1)</remarks>
+/// <remarks>Based on FS 13.1.0 (nnSdk 13.4.0)</remarks>
 public static class PathUtility
 {
     public static void Replace(Span<byte> buffer, byte currentChar, byte newChar)
@@ -46,16 +47,6 @@ public static class PathUtility
                (path.Length < 3 || path[2] == NullTerminator || path[2] == DirectorySeparator);
     }
 
-    public static bool IsSeparator(byte c)
-    {
-        return c == DirectorySeparator;
-    }
-
-    public static bool IsNul(byte c)
-    {
-        return c == NullTerminator;
-    }
-
     public static Result ConvertToFspPath(out FspPath fspPath, ReadOnlySpan<byte> path)
     {
         UnsafeHelpers.SkipParamInit(out fspPath);
@@ -65,7 +56,7 @@ public static class PathUtility
         if (length >= PathTool.EntryNameLengthMax + 1)
             return ResultFs.TooLongPath.Log();
 
-        Result rc = PathFormatter.SkipMountName(out ReadOnlySpan<byte> pathWithoutMountName, out _,
+        Result rc = PathFormatter.SkipMountName(out ReadOnlySpan<byte> pathWithoutMountName, out int skipLength,
             new U8Span(path));
         if (rc.IsFailure()) return rc;
 
@@ -73,10 +64,16 @@ public static class PathUtility
         {
             Replace(SpanHelpers.AsByteSpan(ref fspPath).Slice(0, 0x300), AltDirectorySeparator, DirectorySeparator);
         }
-        else if (fspPath.Str[0] == DirectorySeparator && fspPath.Str[1] == DirectorySeparator)
+        else
         {
-            SpanHelpers.AsByteSpan(ref fspPath)[0] = AltDirectorySeparator;
+            bool isHostOrNoMountName = skipLength == 0 || StringUtils.Compare(path, CommonMountNames.HostRootFileSystemMountName,
-            SpanHelpers.AsByteSpan(ref fspPath)[1] = AltDirectorySeparator;
+                CommonMountNames.HostRootFileSystemMountName.Length) == 0;
+
+            if (isHostOrNoMountName && WindowsPath.IsUncPath(path.Slice(skipLength), true, false))
+            {
+                SpanHelpers.AsByteSpan(ref fspPath)[skipLength] = AltDirectorySeparator;
+                SpanHelpers.AsByteSpan(ref fspPath)[skipLength + 1] = AltDirectorySeparator;
+            }
         }
 
         return Result.Success;

src/LibHac/Fs/Common/WindowsPath.cs

@@ -10,7 +10,7 @@ namespace LibHac.Fs;
 /// <summary>
 /// Contains functions for working with Windows paths.
 /// </summary>
-/// <remarks>Based on FS 12.1.0 (nnSdk 12.3.1)</remarks>
+/// <remarks>Based on FS 13.1.0 (nnSdk 13.4.0)</remarks>
 public static class WindowsPath
 {
     private const int WindowsDriveLength = 2;

src/LibHac/Fs/Fsa/MountUtility.cs

@@ -22,7 +22,7 @@ public static class MountUtility
         if (WindowsPath.IsWindowsDrive(path) || WindowsPath.IsUncPath(path))
         {
             StringUtils.Copy(mountName.Name, CommonPaths.HostRootFileSystemMountName);
-            mountName.Name[PathTool.MountNameLengthMax] = StringTraits.NullTerminator;
+            mountName.Name[PathTool.MountNameLengthMax] = NullTerminator;
 
             subPath = path;
             return Result.Success;
@@ -30,7 +30,7 @@ public static class MountUtility
 
         for (int i = 0; i <= maxMountLen; i++)
         {
-            if (path[i] == StringTraits.DriveSeparator)
+            if (path[i] == DriveSeparator)
             {
                 mountLen = i;
                 break;
@@ -53,7 +53,7 @@ public static class MountUtility
             return ResultFs.InvalidPathFormat.Log();
 
         path.Value.Slice(0, mountLen).CopyTo(mountName.Name);
-        mountName.Name[mountLen] = StringTraits.NullTerminator;
+        mountName.Name[mountLen] = NullTerminator;
         subPath = subPathTemp;
 
         return Result.Success;

src/LibHac/FsSystem/Utility.cs

@@ -1,7 +1,6 @@
 using System;
 using LibHac.Common;
 using LibHac.Fs;
-using LibHac.Fs.Common;
 using LibHac.Fs.Fsa;
 using LibHac.Os;