Merge pull request #16456 from joshuaboniface/fix-path-filesystem-logic

Jellyfin.Server.Implementations/StorageHelpers/StorageHelper.cs

@@ -28,22 +28,44 @@ public static class StorageHelper
     }
 
     /// <summary>
-    /// Gets the free space of a specific directory.
+    /// Gets the free space of the parent filesystem of a specific directory.
     /// </summary>
     /// <param name="path">Path to a folder.</param>
-    /// <returns>The number of bytes available space.</returns>
+    /// <returns>Various details about the parent filesystem containing the directory.</returns>
     public static FolderStorageInfo GetFreeSpaceOf(string path)
     {
         try
         {
-            var driveInfo = new DriveInfo(path);
+            // Fully resolve the given path to an actual filesystem target, in case it's a symlink or similar.
+            var resolvedPath = ResolvePath(path);
+            // We iterate all filesystems reported by GetDrives() here, and attempt to find the best
+            // match that contains, as deep as possible, the given path.
+            // This is required because simply calling `DriveInfo` on a path returns that path as
+            // the Name and RootDevice, which is not at all how this should work.
+            var allDrives = DriveInfo.GetDrives();
+            DriveInfo? bestMatch = null;
+            foreach (DriveInfo d in allDrives)
+            {
+                if (resolvedPath.StartsWith(d.RootDirectory.FullName, StringComparison.InvariantCultureIgnoreCase) &&
+                    (bestMatch is null || d.RootDirectory.FullName.Length > bestMatch.RootDirectory.FullName.Length))
+                {
+                    bestMatch = d;
+                }
+            }
+
+            if (bestMatch is null)
+            {
+                throw new InvalidOperationException($"The path `{path}` has no matching parent device. Space check invalid.");
+            }
+
             return new FolderStorageInfo()
             {
                 Path = path,
-                FreeSpace = driveInfo.AvailableFreeSpace,
-                UsedSpace = driveInfo.TotalSize - driveInfo.AvailableFreeSpace,
-                StorageType = driveInfo.DriveType.ToString(),
-                DeviceId = driveInfo.Name,
+                ResolvedPath = resolvedPath,
+                FreeSpace = bestMatch.AvailableFreeSpace,
+                UsedSpace = bestMatch.TotalSize - bestMatch.AvailableFreeSpace,
+                StorageType = bestMatch.DriveType.ToString(),
+                DeviceId = bestMatch.Name,
             };
         }
         catch
@@ -51,6 +73,7 @@ public static class StorageHelper
             return new FolderStorageInfo()
             {
                 Path = path,
+                ResolvedPath = path,
                 FreeSpace = -1,
                 UsedSpace = -1,
                 StorageType = null,
@@ -59,6 +82,26 @@ public static class StorageHelper
         }
     }
 
+    /// <summary>
+    /// Walk a path and fully resolve any symlinks within it.
+    /// </summary>
+    private static string ResolvePath(string path)
+    {
+        var parts = path.Split(Path.DirectorySeparatorChar, StringSplitOptions.RemoveEmptyEntries);
+        var current = Path.DirectorySeparatorChar.ToString();
+        foreach (var part in parts)
+        {
+            current = Path.Combine(current, part);
+            var resolved = new DirectoryInfo(current).ResolveLinkTarget(returnFinalTarget: true);
+            if (resolved is not null)
+            {
+                current = resolved.FullName;
+            }
+        }
+
+        return current;
+    }
+
     /// <summary>
     /// Gets the underlying drive data from a given path and checks if the available storage capacity matches the threshold.
     /// </summary>

MediaBrowser.Model/System/FolderStorageInfo.cs

@@ -11,17 +11,22 @@ public record FolderStorageInfo
     public required string Path { get; init; }
 
     /// <summary>
-    /// Gets the free space of the underlying storage device of the <see cref="Path"/>.
+    /// Gets the fully resolved path of the folder in question (interpolating any symlinks if present).
+    /// </summary>
+    public required string ResolvedPath { get; init; }
+
+    /// <summary>
+    /// Gets the free space of the underlying storage device of the <see cref="ResolvedPath"/>.
     /// </summary>
     public long FreeSpace { get; init; }
 
     /// <summary>
-    /// Gets the used space of the underlying storage device of the <see cref="Path"/>.
+    /// Gets the used space of the underlying storage device of the <see cref="ResolvedPath"/>.
     /// </summary>
     public long UsedSpace { get; init; }
 
     /// <summary>
-    /// Gets the kind of storage device of the <see cref="Path"/>.
+    /// Gets the kind of storage device of the <see cref="ResolvedPath"/>.
     /// </summary>
     public string? StorageType { get; init; }