From 75378f7bde90b9d3d9b72404c25c017da2cd147c Mon Sep 17 00:00:00 2001
From: Mark McDowall <mark@mcdowall.ca>
Date: Thu, 16 Feb 2023 17:05:39 -0800
Subject: [PATCH] Fixed: USB drives mounted to folders are treated as different
 mounts

Closes #4147
---
 src/NzbDrone.Common/Disk/DiskProviderBase.cs |  2 +-
 src/NzbDrone.Windows/Disk/DiskProvider.cs    | 34 ++++++++++++++++++
 src/NzbDrone.Windows/Disk/FolderMount.cs     | 38 ++++++++++++++++++++
 3 files changed, 73 insertions(+), 1 deletion(-)
 create mode 100644 src/NzbDrone.Windows/Disk/FolderMount.cs

diff --git a/src/NzbDrone.Common/Disk/DiskProviderBase.cs b/src/NzbDrone.Common/Disk/DiskProviderBase.cs
index 23f35981d..d4ead276e 100644
--- a/src/NzbDrone.Common/Disk/DiskProviderBase.cs
+++ b/src/NzbDrone.Common/Disk/DiskProviderBase.cs
@@ -339,7 +339,7 @@ public bool IsFileLocked(string file)
             }
         }
 
-        public string GetPathRoot(string path)
+        public virtual string GetPathRoot(string path)
         {
             Ensure.That(path, () => path).IsValidPath();
 
diff --git a/src/NzbDrone.Windows/Disk/DiskProvider.cs b/src/NzbDrone.Windows/Disk/DiskProvider.cs
index d8b9dc448..3200e669b 100644
--- a/src/NzbDrone.Windows/Disk/DiskProvider.cs
+++ b/src/NzbDrone.Windows/Disk/DiskProvider.cs
@@ -26,6 +26,22 @@ private static extern bool GetDiskFreeSpaceEx(string lpDirectoryName,
         [return: MarshalAs(UnmanagedType.Bool)]
         private static extern bool CreateHardLink(string lpFileName, string lpExistingFileName, IntPtr lpSecurityAttributes);
 
+        public override IMount GetMount(string path)
+        {
+            var reparsePoint = GetReparsePoint(path);
+
+            return reparsePoint ?? base.GetMount(path);
+        }
+
+        public override string GetPathRoot(string path)
+        {
+            Ensure.That(path, () => path).IsValidPath();
+
+            var reparsePoint = GetReparsePoint(path);
+
+            return reparsePoint?.RootDirectory ?? base.GetPathRoot(path);
+        }
+
         public override long? GetAvailableSpace(string path)
         {
             Ensure.That(path, () => path).IsValidPath();
@@ -171,5 +187,23 @@ public override bool TryCreateHardLink(string source, string destination)
                 return false;
             }
         }
+
+        private IMount GetReparsePoint(string path)
+        {
+            var di = new DirectoryInfo(path);
+            var isReparsePoint = di.Attributes.HasFlag(FileAttributes.ReparsePoint);
+
+            while (!isReparsePoint && (di = di.Parent) != null)
+            {
+                isReparsePoint = di.Attributes.HasFlag(FileAttributes.ReparsePoint);
+            }
+
+            if (isReparsePoint)
+            {
+                return new FolderMount(di);
+            }
+
+            return null;
+        }
     }
 }
diff --git a/src/NzbDrone.Windows/Disk/FolderMount.cs b/src/NzbDrone.Windows/Disk/FolderMount.cs
new file mode 100644
index 000000000..65fbcf5de
--- /dev/null
+++ b/src/NzbDrone.Windows/Disk/FolderMount.cs
@@ -0,0 +1,38 @@
+using System.IO;
+using NzbDrone.Common.Disk;
+using NzbDrone.Common.Extensions;
+
+namespace NzbDrone.Windows.Disk
+{
+    public class FolderMount : IMount
+    {
+        private readonly DirectoryInfo _directoryInfo;
+
+        public FolderMount(DirectoryInfo directoryInfo)
+        {
+            _directoryInfo = directoryInfo;
+        }
+
+        public long AvailableFreeSpace => 0;
+
+        public string DriveFormat => "NTFS";
+
+        public DriveType DriveType => DriveType.Removable;
+
+        public bool IsReady => true;
+
+        public MountOptions MountOptions { get; private set; }
+
+        public string Name => _directoryInfo.Name;
+
+        public string RootDirectory => _directoryInfo.FullName;
+
+        public long TotalFreeSpace => 0;
+
+        public long TotalSize => 0;
+
+        public string VolumeLabel => _directoryInfo.Name;
+
+        public string VolumeName => Name;
+    }
+}