Upload FastSeekWpf/Core/MftReader.cs

FastSeekWpf/Core/MftReader.cs

@@ -21,25 +21,14 @@ public class MftReader : IDisposable
     public MftReader(NtfsDrive drive)
     {
         _drive = drive;
-
-        // Open volume device for boot sector read (matches Rust MftReader::open exactly)
-        var pathBytes = System.Text.Encoding.Unicode.GetBytes(drive.DevicePath + '\0');
-        GCHandle pathHandle = GCHandle.Alloc(pathBytes, GCHandleType.Pinned);
-        try
-        {
-            _volumeHandle = Win32Api.CreateFileW(
-                drive.DevicePath,
-                Win32Api.GENERIC_READ,
-                Win32Api.FILE_SHARE_READ | Win32Api.FILE_SHARE_WRITE | Win32Api.FILE_SHARE_DELETE,
-                IntPtr.Zero,
-                Win32Api.OPEN_EXISTING,
-                Win32Api.FILE_FLAG_BACKUP_SEMANTICS,
-                IntPtr.Zero);
-        }
-        finally
-        {
-            pathHandle.Free();
-        }
+        _volumeHandle = Win32Api.CreateFileW(
+            drive.DevicePath,
+            Win32Api.GENERIC_READ,
+            Win32Api.FILE_SHARE_READ | Win32Api.FILE_SHARE_WRITE | Win32Api.FILE_SHARE_DELETE,
+            IntPtr.Zero,
+            Win32Api.OPEN_EXISTING,
+            Win32Api.FILE_FLAG_BACKUP_SEMANTICS,
+            IntPtr.Zero);
 
         if (_volumeHandle == new IntPtr(-1))
         {
@@ -49,9 +38,14 @@ public class MftReader : IDisposable
     }
 
     // ------------------------------------------------------------------
-    //  Primary: direct $MFT file read (matches Rust scan_direct exactly)
+    //  Primary: direct $MFT file read  (falls back to FSCTL if fails)
+    //  Matches Rust scan_direct() + scan() exactly.
     // ------------------------------------------------------------------
 
+    /// <summary>
+    /// Try direct sequential read of $MFT for maximum speed.
+    /// Returns null if direct access is unavailable (matches Rust .ok()?).
+    /// </summary>
     public ScanResult? ScanDirect()
     {
         int? recordSize = ReadMftRecordSize();
@@ -60,19 +54,19 @@ public class MftReader : IDisposable
         string mftPath = $"{_drive.Root}$MFT";
         Logger.Log($"[{Drive.Letter}] Opening $MFT: {mftPath}");
 
-        IntPtr mftHandle = OpenMftFile(mftPath);
-        if (mftHandle == new IntPtr(-1))
-        {
-            // Try extended-length path prefix as fallback
-            string extendedPath = $"\\\\?\\{mftPath}";
-            Logger.Log($"[{Drive.Letter}] Retrying with extended path: {extendedPath}");
-            mftHandle = OpenMftFile(extendedPath);
-        }
+        IntPtr mftHandle = Win32Api.CreateFileW(
+            mftPath,
+            Win32Api.GENERIC_READ,
+            Win32Api.FILE_SHARE_READ | Win32Api.FILE_SHARE_WRITE | Win32Api.FILE_SHARE_DELETE,
+            IntPtr.Zero,
+            Win32Api.OPEN_EXISTING,
+            Win32Api.FILE_FLAG_BACKUP_SEMANTICS | Win32Api.FILE_FLAG_SEQUENTIAL_SCAN,
+            IntPtr.Zero);
 
         if (mftHandle == new IntPtr(-1))
         {
             int err = Marshal.GetLastWin32Error();
-            Logger.Log($"[{Drive.Letter}] CreateFileW($MFT) failed: {Win32Error(err)} (code={err})");
+            Logger.Log($"[{Drive.Letter}] CreateFileW({mftPath}) failed: {Win32Error(err)} (code={err})");
             return null;
         }
 
@@ -90,7 +84,7 @@ public class MftReader : IDisposable
                 bool ok = Win32Api.ReadFile(
                     mftHandle, buffer, leftover, (uint)(buffer.Length - leftover), out bytesRead, IntPtr.Zero);
 
-                if (!ok || bytesRead == 0)
+                if (ok.is_err() || bytesRead == 0)
                     break;
 
                 int total = leftover + (int)bytesRead;
@@ -112,7 +106,7 @@ public class MftReader : IDisposable
                     offset += recordSize.Value;
                 }
 
-                // Align down to record boundary (matches Rust: offset = total - (total % record_size))
+                // Align offset down to record boundary (matches Rust: offset = total - (total % record_size))
                 offset = total - (total % recordSize.Value);
 
                 leftover = total - offset;
@@ -132,20 +126,9 @@ public class MftReader : IDisposable
         }
     }
 
-    private static IntPtr OpenMftFile(string path)
-    {
-        return Win32Api.CreateFileW(
-            path,
-            Win32Api.GENERIC_READ,
-            Win32Api.FILE_SHARE_READ | Win32Api.FILE_SHARE_WRITE | Win32Api.FILE_SHARE_DELETE,
-            IntPtr.Zero,
-            Win32Api.OPEN_EXISTING,
-            Win32Api.FILE_FLAG_BACKUP_SEMANTICS | Win32Api.FILE_FLAG_SEQUENTIAL_SCAN,
-            IntPtr.Zero);
-    }
-
     // ------------------------------------------------------------------
-    //  Fallback: FSCTL_ENUM_USN_DATA (matches Rust scan exactly)
+    //  Fallback: FSCTL_ENUM_USN_DATA (4 MB buffer)
+    //  Matches Rust scan() exactly.
     // ------------------------------------------------------------------
 
     public ScanResult Scan()
@@ -196,7 +179,7 @@ public class MftReader : IDisposable
                         }
                         if (error == 122) // ERROR_INSUFFICIENT_BUFFER
                         {
-                            Logger.Log($"[{Drive.Letter}] FSCTL buffer too small, retrying with {buffer.Length * 2}");
+                            Logger.Log($"[{Drive.Letter}] FSCTL buffer too small ({buffer.Length}), retrying");
                             buffer = new byte[buffer.Length * 2];
                             continue;
                         }
@@ -205,10 +188,7 @@ public class MftReader : IDisposable
                     }
 
                     if (bytesReturned <= 8)
-                    {
-                        Logger.Log($"[{Drive.Letter}] FSCTL: {bytesReturned} bytes returned, stopping");
                         break;
-                    }
 
                     ulong nextRef = (ulong)Marshal.ReadInt64(bufferPtr);
                     enumData.StartFileReferenceNumber = nextRef;
@@ -268,7 +248,7 @@ public class MftReader : IDisposable
 
     private int? ReadMftRecordSize()
     {
-        // Seek to start of volume
+        // Seek to beginning of volume
         Win32Api.SetFilePointerEx(_volumeHandle, 0, out _, 0);
 
         byte[] boot = new byte[512];