Merge pull request #4277 from dgehri/feature/USN-deleted-files-fix

Enabled support for \$Extend\$Deleted special MTF folder when using USN

1 files changed, 49 insertions, 15 deletions

diff --git a/Duplicati/Library/Snapshots/USNJournal.cs b/Duplicati/Library/Snapshots/USNJournal.cs
index 111a871b3..ef020df88 100644
--- a/Duplicati/Library/Snapshots/USNJournal.cs
+++ b/Duplicati/Library/Snapshots/USNJournal.cs
@@ -87,6 +87,11 @@ namespace Duplicati.Library.Snapshots
         private SafeFileHandle m_volumeHandle;

 

         /// <summary>

+        /// Determined file ref number of "\$Extend\$Deleted\" folder

+        /// </summary>

+        private ulong? m_extendDeletedRefNr = null;

+

+        /// <summary>

         /// Constructs a new USN helper instance

         /// </summary>

         /// <param name="volumeRoot">The root volume where the USN lookup is performed</param>

@@ -382,7 +387,7 @@ namespace Duplicati.Library.Snapshots
 

                     if (e == Win32USN.ERROR_INSUFFICIENT_BUFFER)

                     {

-                        bufferSize = bufferSize * 2;

+                        bufferSize *= 2;

                         continue;

                     }

 

@@ -423,13 +428,16 @@ namespace Duplicati.Library.Snapshots
                     return null;

 

                 // retry, increasing buffer size

-                bufferSize = bufferSize * 2;

+                bufferSize *= 2;

             }

 

             // not really a foreach: we only check the first record

             foreach (var rec in EnumerateRecords(entryData))

+            {

                 if (rec.UsnRecord.FileReferenceNumber == frn)

                     return rec;

+                break;

+            }

 

             return null;

         }

@@ -476,6 +484,29 @@ namespace Duplicati.Library.Snapshots
                     {

                         // parent FRN not found in look-up table, fetch it from change journal

                         var parentRecord = GetRecordByFileRef(parentRefNr);

+

+                        if (parentRecord == null 

+                            && (cur.UsnRecord.Reason & Win32USN.USNReason.USN_REASON_RENAME_NEW_NAME) == Win32USN.USNReason.USN_REASON_RENAME_NEW_NAME)

+                        {

+                            // check if this file was moved to the special \$Extend\$Deleted folder

+                            // we do so by comparing its file name against the file reference number

+                            if (cur.FileName.Length > 16 

+                                && cur.UsnRecord.FileReferenceNumber.ToString("X16") == cur.FileName.Substring(0, 16))

+                            {

+                                // as a safety precaution, we ensure that the FileReferenceNumber for " \$Extend\$Deleted" 

+                                // determined in this way is the same for *all* files

+                                if (!m_extendDeletedRefNr.HasValue)

+                                {

+                                    m_extendDeletedRefNr = parentRefNr;

+                                }

+                                else if (m_extendDeletedRefNr.Value != parentRefNr)

+                                    throw new UsnJournalSoftFailureException(Strings.USNHelper.PathResolveError);

+

+                                pathList.Clear();

+                                break;

+                            }

+                        }

+

                         parents = new SortedRecords(new List<Record> { parentRecord });

                         cache.Add(parentRefNr, parents);

                     }

@@ -490,22 +521,25 @@ namespace Duplicati.Library.Snapshots
                     cur = parent;

                 }

 

-                // generate full path

-                Debug.Assert(m_volume != null, nameof(m_volume) + " != null");

-                var path = m_volume;

-                foreach (var r in pathList)

+                if (pathList.Count > 0)

                 {

-                    path = SystemIO.IO_WIN.PathCombine(path, r.FileName);

-                }

+                    // generate full path

+                    Debug.Assert(m_volume != null, nameof(m_volume) + " != null");

+                    var path = m_volume;

+                    foreach (var r in pathList)

+                    {

+                        path = SystemIO.IO_WIN.PathCombine(path, r.FileName);

+                    }

 

-                if (rec.UsnRecord.FileAttributes.HasFlag(Win32USN.FileAttributes.Directory))

-                {

-                    path = Util.AppendDirSeparator(path);

-                }

+                    if (rec.UsnRecord.FileAttributes.HasFlag(Win32USN.FileAttributes.Directory))

+                    {

+                        path = Util.AppendDirSeparator(path);

+                    }

 

-                // set resolved path

-                rec.FullPath = path;

-                result.Add(rec);

+                    // set resolved path

+                    rec.FullPath = path;

+                    result.Add(rec);

+                }

             }

 

             return result;