Enable OpenHostFileSystem in FileSystemProxy and add XML docs

src/LibHac/Fs/FsEnums.cs

@@ -188,6 +188,7 @@ namespace LibHac.Fs
         SdCard = 2
     }
 
+    [Flags]
     public enum MountHostOption
     {
         None = 0,

src/LibHac/Fs/Shim/Host.cs

@@ -8,6 +8,12 @@ using static LibHac.Fs.CommonMountNames;
 
 namespace LibHac.Fs.Shim
 {
+    /// <summary>
+    /// Contains functions for mounting file systems from a host computer.
+    /// </summary>
+    /// <remarks>
+    /// All functions in this file are based on SDK 9.3
+    /// </remarks>
     public static class Host
     {
         private static ReadOnlySpan<byte> HostRootFileSystemPath => new[]
@@ -59,6 +65,11 @@ namespace LibHac.Fs.Shim
             }
         }
 
+        /// <summary>
+        /// Mounts the C:\ drive of a host Windows computer at @Host:/
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         public static Result MountHostRoot(this FileSystemClient fs)
         {
             IFileSystem hostFileSystem = default;
@@ -87,6 +98,12 @@ namespace LibHac.Fs.Shim
             return Result.Success;
         }
 
+        /// <summary>
+        /// Mounts the C:\ drive of a host Windows computer at @Host:/
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="option">Options for mounting the host file system.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         public static Result MountHostRoot(this FileSystemClient fs, MountHostOption option)
         {
             IFileSystem hostFileSystem = default;
@@ -116,21 +133,49 @@ namespace LibHac.Fs.Shim
             return Result.Success;
         }
 
+        /// <summary>
+        /// Unmounts the file system at @Host:/
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
         public static void UnmountHostRoot(this FileSystemClient fs)
         {
             fs.Unmount(HostRootFileSystemMountName);
         }
 
+        /// <summary>
+        /// Mounts a directory on a host Windows computer at the specified mount point.
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="mountName">The mount name at which the file system will be mounted.</param>
+        /// <param name="path">The path on the host computer to mount. e.g. C:\Windows\System32</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         public static Result MountHost(this FileSystemClient fs, U8Span mountName, U8Span path)
         {
             return MountHostImpl(fs, mountName, path, null);
         }
 
+        /// <summary>
+        /// Mounts a directory on a host Windows computer at the specified mount point.
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="mountName">The mount name at which the file system will be mounted.</param>
+        /// <param name="path">The path on the host computer to mount. e.g. C:\Windows\System32</param>
+        /// <param name="option">Options for mounting the host file system.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         public static Result MountHost(this FileSystemClient fs, U8Span mountName, U8Span path, MountHostOption option)
         {
             return MountHostImpl(fs, mountName, path, option);
         }
 
+        /// <summary>
+        /// Mounts a directory on a host Windows computer at the specified mount point.
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="mountName">The mount name at which the file system will be mounted.</param>
+        /// <param name="path">The path on the host computer to mount. e.g. C:\Windows\System32</param>
+        /// <param name="optionalOption">Options for mounting the host file system. Specifying this parameter is optional.</param>
+        /// <param name="caller">The caller of this function.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         private static Result MountHostImpl(this FileSystemClient fs, U8Span mountName, U8Span path,
             MountHostOption? optionalOption, [CallerMemberName] string caller = "")
         {
@@ -210,6 +255,14 @@ namespace LibHac.Fs.Shim
             return Result.Success;
         }
 
+        /// <summary>
+        /// Creates an <see cref="ICommonMountNameGenerator"/> based on the <paramref name="mountName"/> and
+        /// <paramref name="path"/>, and verifies the <paramref name="mountName"/>.
+        /// </summary>
+        /// <param name="nameGenerator">If successful, the created <see cref="ICommonMountNameGenerator"/>.</param>
+        /// <param name="mountName">The mount name at which the file system will be mounted.</param>
+        /// <param name="path">The path that will be opened on the host computer. e.g. C:\Windows\System32</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         private static Result PreMountHost(out ICommonMountNameGenerator nameGenerator, U8Span mountName, U8Span path)
         {
             nameGenerator = default;
@@ -224,6 +277,15 @@ namespace LibHac.Fs.Shim
             return Result.Success;
         }
 
+        /// <summary>
+        /// Verifies parameters and opens a host file system.
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="fileSystem">If successful, the opened host file system.</param>
+        /// <param name="mountName">The mount name to be verified.</param>
+        /// <param name="path">The path on the host computer to open. e.g. C:\Windows\System32</param>
+        /// <param name="option">Options for opening the host file system.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         private static Result OpenHostFileSystem(FileSystemClient fs, out IFileSystem fileSystem, U8Span mountName,
             U8Span path, MountHostOption option)
         {
@@ -279,6 +341,14 @@ namespace LibHac.Fs.Shim
             return OpenHostFileSystemImpl(fs, out fileSystem, ref fullPath, option);
         }
 
+        /// <summary>
+        /// Opens a host file system via <see cref="IFileSystemProxy"/>.
+        /// </summary>
+        /// <param name="fs">The <see cref="FileSystemClient"/> to use.</param>
+        /// <param name="fileSystem">If successful, the opened host file system.</param>
+        /// <param name="path">The path on the host computer to open. e.g. /C:\Windows\System32/</param>
+        /// <param name="option">Options for opening the host file system.</param>
+        /// <returns>The <see cref="Result"/> of the operation.</returns>
         private static Result OpenHostFileSystemImpl(FileSystemClient fs, out IFileSystem fileSystem, ref FsPath path, MountHostOption option)
         {
             fileSystem = default;

src/LibHac/FsService/FileSystemProxy.cs

@@ -684,12 +684,14 @@ namespace LibHac.FsService
 
         public Result OpenHostFileSystemWithOption(out IFileSystem fileSystem, ref FsPath path, MountHostOption option)
         {
-            throw new NotImplementedException();
+            // Missing permission check
+
+            return FsProxyCore.OpenHostFileSystem(out fileSystem, new U8Span(path.Str), option.HasFlag(MountHostOption.PseudoCaseSensitive));
         }
 
         public Result OpenHostFileSystem(out IFileSystem fileSystem, ref FsPath path)
         {
-            throw new NotImplementedException();
+            return OpenHostFileSystemWithOption(out fileSystem, ref path, MountHostOption.None);
         }
 
         public Result OpenSdCardFileSystem(out IFileSystem fileSystem)

src/LibHac/FsService/FileSystemProxyCore.cs

@@ -772,7 +772,8 @@ namespace LibHac.FsService
 
             if (path.IsEmpty())
             {
-                rc = hostFs.GetEntryType(out _, "C:/".ToU8Span());
+                ReadOnlySpan<byte> rootHostPath = new[] { (byte)'C', (byte)':', (byte)'/' };
+                rc = hostFs.GetEntryType(out _, new U8Span(rootHostPath));
 
                 // Nintendo ignores all results other than this one
                 if (ResultFs.TargetNotFound.Includes(rc))

tests/LibHac.Tests/PathToolsTests.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using LibHac.Common;
-using LibHac.Fs;
 using LibHac.FsSystem;
 using Xunit;