/// <summary> /// Handles a specific file along with a group of files already seen with the same size. /// </summary> /// <param name="item">The item.</param> /// <param name="configuration">The configuration.</param> /// <param name="stats">The statistics.</param> /// <param name="knownWithThisLength">Length of the known with this.</param> private static void _HandleFileWithGivenSize( FileInfo item, Configuration configuration, RuntimeStats stats, ConcurrentDictionary <string, FileEntry> knownWithThisLength) { var myKey = _GenerateKey(item); var checksum = knownWithThisLength.GetOrAdd(myKey, new FileEntry(item)); var isHardLink = false; IEnumerable <FileInfo> hardlinks; try { hardlinks = item.GetHardLinkTargets(); } catch (Exception e) { _RemoveFileEntry(item, knownWithThisLength); Console.WriteLine($"[Error] Could not enumerate HardLinks {item.FullName}: {e.Message}"); return; } foreach (var target in hardlinks) { isHardLink = true; knownWithThisLength.TryAdd(_GenerateKey(target), new FileEntry(target)); } if (isHardLink) { stats.HardLinkStats.IncreaseSeen(); if (configuration.ShowInfoOnly) { return; } _HandleExistingHardLink(item, configuration, stats, knownWithThisLength); return; } string symlink; try { symlink = item.GetSymbolicLinkTarget(); } catch (Exception e) { _RemoveFileEntry(item, knownWithThisLength); Console.WriteLine($"[Error] Could not enumerate SymLink {item.FullName}: {e.Message}"); return; } if (symlink != null) { knownWithThisLength.TryAdd(symlink, new FileEntry(new FileInfo(symlink))); stats.SymbolicLinkStats.IncreaseSeen(); if (configuration.ShowInfoOnly) { return; } _HandleExistingSymbolicLink(item, configuration, stats, knownWithThisLength); return; } if (configuration.ShowInfoOnly) { return; } // find matching file in seen list and try to hard or symlink var sameFiles = knownWithThisLength .Where(kvp => kvp.Key != myKey) .Where(kvp => kvp.Value.Equals(checksum)) .Select(kvp => kvp.Key) ; foreach (var sameFile in sameFiles) { var temporaryFile = _CreateTemporaryFileInSameDirectory(item); temporaryFile.Delete(); var isSymlink = false; try { LinkExtensions.CreateHardLinkFrom((FileInfo)temporaryFile, (string)sameFile); } catch (Exception e1) { if (configuration.AlsoTrySymbolicLinks) { isSymlink = true; try { LinkExtensions.CreateSymbolicLinkFrom((FileInfo)temporaryFile, (string)sameFile); } catch (Exception e2) { Console.WriteLine( $"[Warning] Could not Symlink {item.FullName}({FilesizeFormatter.FormatUnit(item.Length, true)}) --> {sameFile}: {e2.Message}"); continue; } } else { Console.WriteLine( $"[Warning] Could not Hardlink {item.FullName}({FilesizeFormatter.FormatUnit(item.Length, true)}) --> {sameFile}: {e1.Message}"); continue; } } var isAlreadyDeleted = false; try { item.Attributes &= ~FileAttributes.ReadOnly; item.Delete(); isAlreadyDeleted = true; File.Move(temporaryFile.FullName, item.FullName); } catch { if (isAlreadyDeleted) { // undo file deletion temporaryFile.CopyTo(item.FullName, true); } else { // undo temp file creation temporaryFile.Delete(); } throw; } if (isSymlink) { stats.SymbolicLinkStats.IncreaseCreated(); if (configuration.SetReadOnlyAttributeOnNewSymbolicLinks) { item.Attributes |= FileAttributes.ReadOnly; } } else { stats.HardLinkStats.IncreaseCreated(); if (configuration.SetReadOnlyAttributeOnNewHardLinks) { item.Attributes |= FileAttributes.ReadOnly; } } Console.WriteLine($"[Info] Created {(isSymlink ? "Symlink" : "Hardlink")} for {item.FullName}({FilesizeFormatter.FormatUnit(item.Length, true)}) --> {sameFile}"); return; } }