diff --git a/changelog/unreleased/issue-4817 b/changelog/unreleased/issue-4817 index b8ffc35ca..ddbd5672b 100644 --- a/changelog/unreleased/issue-4817 +++ b/changelog/unreleased/issue-4817 @@ -1,11 +1,22 @@ Enhancement: Make overwrite behavior of `restore` customizable The `restore` command now supports an `--overwrite` option to configure whether -already existing files are overwritten. The default is `--overwrite always`, -which overwrites existing files. `--overwrite if-newer` only restores files -from the snapshot that are newer than the local state. And `--overwrite never` -does not modify existing files. +already existing files are overwritten. This behavior can now be configured via +the `--overwrite` option. The following values are supported: + +* `--overwrite always` (default): always overwrites already existing files. `restore` + will verify the existing file content and only restore mismatching parts to minimize + downloads. Updates the metadata of all files. +* `--overwrite if-changed`: like the previous case, but speeds up the file content check + by assuming that files with matching size and modification time (mtime) are already up to date. + In case of a mismatch, the full file content is verified. Updates the metadata of all files. +* `--overwrite if-newer`: only overwrite existing files if the file in the snapshot has a + newer modification time (mtime). +* `--overwrite never`: never overwrite existing files. https://github.com/restic/restic/issues/4817 https://github.com/restic/restic/issues/200 +https://github.com/restic/restic/issues/407 +https://github.com/restic/restic/issues/2662 https://github.com/restic/restic/pull/4837 +https://github.com/restic/restic/pull/4838 diff --git a/cmd/restic/cmd_restore.go b/cmd/restic/cmd_restore.go index 361eb59a8..f39db6a76 100644 --- a/cmd/restic/cmd_restore.go +++ b/cmd/restic/cmd_restore.go @@ -66,7 +66,7 @@ func init() { initSingleSnapshotFilter(flags, &restoreOptions.SnapshotFilter) flags.BoolVar(&restoreOptions.Sparse, "sparse", false, "restore files as sparse") flags.BoolVar(&restoreOptions.Verify, "verify", false, "verify restored files content") - flags.Var(&restoreOptions.Overwrite, "overwrite", "overwrite behavior, one of (always|if-newer|never) (default: always)") + flags.Var(&restoreOptions.Overwrite, "overwrite", "overwrite behavior, one of (always|if-changed|if-newer|never) (default: always)") } func runRestore(ctx context.Context, opts RestoreOptions, gopts GlobalOptions, diff --git a/doc/050_restore.rst b/doc/050_restore.rst index 637ffc337..9c24f09de 100644 --- a/doc/050_restore.rst +++ b/doc/050_restore.rst @@ -91,11 +91,26 @@ stored explicitly. Restoring in-place ------------------ -By default, the ``restore`` command overwrites already existing files in the target -directory. This behavior can be configured via the ``--overwrite`` option. The -default is ``--overwrite always``. To only overwrite existing files if the file in -the snapshot is newer, use ``--overwrite if-newer``. To never overwrite existing files, -use ``--overwrite never``. +.. note:: + + Restoring data in-place can leave files in a partially restored state if the ``restore`` + operation is interrupted. To ensure you can revert back to the previous state, create + a current ``backup`` before restoring a different snapshot. + +By default, the ``restore`` command overwrites already existing files at the target +directory. This behavior can be configured via the ``--overwrite`` option. The following +values are supported: + +* ``--overwrite always`` (default): always overwrites already existing files. ``restore`` + will verify the existing file content and only restore mismatching parts to minimize + downloads. Updates the metadata of all files. +* ``--overwrite if-changed``: like the previous case, but speeds up the file content check + by assuming that files with matching size and modification time (mtime) are already up to date. + In case of a mismatch, the full file content is verified. Updates the metadata of all files. +* ``--overwrite if-newer``: only overwrite existing files if the file in the snapshot has a + newer modification time (mtime). +* ``--overwrite never``: never overwrite existing files. + Restore using mount =================== diff --git a/internal/restic/node_windows.go b/internal/restic/node_windows.go index 9117c6a10..0d96bdb98 100644 --- a/internal/restic/node_windows.go +++ b/internal/restic/node_windows.go @@ -275,17 +275,20 @@ func fixEncryptionAttribute(path string, attrs *uint32, pathPointer *uint16) (er // File should be encrypted. err = encryptFile(pathPointer) if err != nil { - if fs.IsAccessDenied(err) { + if fs.IsAccessDenied(err) || errors.Is(err, windows.ERROR_FILE_READ_ONLY) { // If existing file already has readonly or system flag, encrypt file call fails. - // We have already cleared readonly flag, clearing system flag if needed. // The readonly and system flags will be set again at the end of this func if they are needed. + err = fs.ResetPermissions(path) + if err != nil { + return fmt.Errorf("failed to encrypt file: failed to reset permissions: %s : %v", path, err) + } err = fs.ClearSystem(path) if err != nil { return fmt.Errorf("failed to encrypt file: failed to clear system flag: %s : %v", path, err) } err = encryptFile(pathPointer) if err != nil { - return fmt.Errorf("failed to encrypt file: %s : %v", path, err) + return fmt.Errorf("failed retry to encrypt file: %s : %v", path, err) } } else { return fmt.Errorf("failed to encrypt file: %s : %v", path, err) @@ -300,17 +303,20 @@ func fixEncryptionAttribute(path string, attrs *uint32, pathPointer *uint16) (er // File should not be encrypted, but its already encrypted. Decrypt it. err = decryptFile(pathPointer) if err != nil { - if fs.IsAccessDenied(err) { + if fs.IsAccessDenied(err) || errors.Is(err, windows.ERROR_FILE_READ_ONLY) { // If existing file already has readonly or system flag, decrypt file call fails. - // We have already cleared readonly flag, clearing system flag if needed. // The readonly and system flags will be set again after this func if they are needed. + err = fs.ResetPermissions(path) + if err != nil { + return fmt.Errorf("failed to encrypt file: failed to reset permissions: %s : %v", path, err) + } err = fs.ClearSystem(path) if err != nil { return fmt.Errorf("failed to decrypt file: failed to clear system flag: %s : %v", path, err) } err = decryptFile(pathPointer) if err != nil { - return fmt.Errorf("failed to decrypt file: %s : %v", path, err) + return fmt.Errorf("failed retry to decrypt file: %s : %v", path, err) } } else { return fmt.Errorf("failed to decrypt file: %s : %v", path, err) diff --git a/internal/restorer/filerestorer.go b/internal/restorer/filerestorer.go index 600a702b2..f57d58598 100644 --- a/internal/restorer/filerestorer.go +++ b/internal/restorer/filerestorer.go @@ -26,6 +26,7 @@ type fileInfo struct { size int64 location string // file on local filesystem relative to restorer basedir blobs interface{} // blobs of the file + state *fileState } type fileBlobInfo struct { @@ -80,25 +81,25 @@ func newFileRestorer(dst string, } } -func (r *fileRestorer) addFile(location string, content restic.IDs, size int64) { - r.files = append(r.files, &fileInfo{location: location, blobs: content, size: size}) +func (r *fileRestorer) addFile(location string, content restic.IDs, size int64, state *fileState) { + r.files = append(r.files, &fileInfo{location: location, blobs: content, size: size, state: state}) } func (r *fileRestorer) targetPath(location string) string { return filepath.Join(r.dst, location) } -func (r *fileRestorer) forEachBlob(blobIDs []restic.ID, fn func(packID restic.ID, packBlob restic.Blob)) error { +func (r *fileRestorer) forEachBlob(blobIDs []restic.ID, fn func(packID restic.ID, packBlob restic.Blob, idx int)) error { if len(blobIDs) == 0 { return nil } - for _, blobID := range blobIDs { + for i, blobID := range blobIDs { packs := r.idx(restic.DataBlob, blobID) if len(packs) == 0 { return errors.Errorf("Unknown blob %s", blobID.String()) } - fn(packs[0].PackID, packs[0].Blob) + fn(packs[0].PackID, packs[0].Blob, i) } return nil @@ -128,8 +129,8 @@ func (r *fileRestorer) restoreFiles(ctx context.Context) error { packsMap = make(map[restic.ID][]fileBlobInfo) } fileOffset := int64(0) - err := r.forEachBlob(fileBlobs, func(packID restic.ID, blob restic.Blob) { - if largeFile { + err := r.forEachBlob(fileBlobs, func(packID restic.ID, blob restic.Blob, idx int) { + if largeFile && !file.state.HasMatchingBlob(idx) { packsMap[packID] = append(packsMap[packID], fileBlobInfo{id: blob.ID, offset: fileOffset}) fileOffset += int64(blob.DataLength()) } @@ -152,6 +153,12 @@ func (r *fileRestorer) restoreFiles(ctx context.Context) error { // in addition, a short chunk will never match r.zeroChunk which would prevent sparseness for short files file.sparse = r.sparse } + if file.state != nil { + // The restorer currently cannot punch new holes into an existing files. + // Thus sections that contained data but should be sparse after restoring + // the snapshot would still contain the old data resulting in a corrupt restore. + file.sparse = false + } if err != nil { // repository index is messed up, can't do anything @@ -232,8 +239,8 @@ func (r *fileRestorer) downloadPack(ctx context.Context, pack *packInfo) error { } if fileBlobs, ok := file.blobs.(restic.IDs); ok { fileOffset := int64(0) - err := r.forEachBlob(fileBlobs, func(packID restic.ID, blob restic.Blob) { - if packID.Equal(pack.id) { + err := r.forEachBlob(fileBlobs, func(packID restic.ID, blob restic.Blob, idx int) { + if packID.Equal(pack.id) && !file.state.HasMatchingBlob(idx) { addBlob(blob, fileOffset) } fileOffset += int64(blob.DataLength()) diff --git a/internal/restorer/fileswriter.go b/internal/restorer/fileswriter.go index 5e4931c63..50f06c83d 100644 --- a/internal/restorer/fileswriter.go +++ b/internal/restorer/fileswriter.go @@ -40,9 +40,8 @@ func newFilesWriter(count int) *filesWriter { } func createFile(path string, createSize int64, sparse bool) (*os.File, error) { - var f *os.File - var err error - if f, err = os.OpenFile(path, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0600); err != nil { + f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600) + if err != nil { if !fs.IsAccessDenied(err) { return nil, err } @@ -54,19 +53,31 @@ func createFile(path string, createSize int64, sparse bool) (*os.File, error) { if err = fs.ResetPermissions(path); err != nil { return nil, err } - if f, err = os.OpenFile(path, os.O_TRUNC|os.O_WRONLY, 0600); err != nil { + if f, err = os.OpenFile(path, os.O_WRONLY, 0600); err != nil { return nil, err } } - if createSize > 0 { - if sparse { - err = truncateSparse(f, createSize) + if sparse { + err = truncateSparse(f, createSize) + if err != nil { + _ = f.Close() + return nil, err + } + } else { + info, err := f.Stat() + if err != nil { + _ = f.Close() + return nil, err + } + if info.Size() > createSize { + // file is too long must shorten it + err = f.Truncate(createSize) if err != nil { _ = f.Close() return nil, err } - } else { + } else if createSize > 0 { err := fs.PreallocateFile(f, createSize) if err != nil { // Just log the preallocate error but don't let it cause the restore process to fail. @@ -78,7 +89,7 @@ func createFile(path string, createSize int64, sparse bool) (*os.File, error) { } } } - return f, err + return f, nil } func (w *filesWriter) writeToFile(path string, blob []byte, offset int64, createSize int64, sparse bool) error { diff --git a/internal/restorer/restorer.go b/internal/restorer/restorer.go index 84b786997..6002d6f0e 100644 --- a/internal/restorer/restorer.go +++ b/internal/restorer/restorer.go @@ -3,6 +3,7 @@ package restorer import ( "context" "fmt" + "io" "os" "path/filepath" "sync/atomic" @@ -18,13 +19,11 @@ import ( // Restorer is used to restore a snapshot to a directory. type Restorer struct { - repo restic.Repository - sn *restic.Snapshot - sparse bool - progress *restoreui.Progress - overwrite OverwriteBehavior + repo restic.Repository + sn *restic.Snapshot + opts Options - fileList map[string]struct{} + fileList map[string]bool Error func(location string, err error) error Warn func(message string) @@ -43,10 +42,13 @@ type OverwriteBehavior int // Constants for different overwrite behavior const ( - OverwriteAlways OverwriteBehavior = 0 - OverwriteIfNewer OverwriteBehavior = 1 - OverwriteNever OverwriteBehavior = 2 - OverwriteInvalid OverwriteBehavior = 3 + OverwriteAlways OverwriteBehavior = iota + // OverwriteIfChanged is like OverwriteAlways except that it skips restoring the content + // of files with matching size&mtime. Metatdata is always restored. + OverwriteIfChanged + OverwriteIfNewer + OverwriteNever + OverwriteInvalid ) // Set implements the method needed for pflag command flag parsing. @@ -54,6 +56,8 @@ func (c *OverwriteBehavior) Set(s string) error { switch s { case "always": *c = OverwriteAlways + case "if-changed": + *c = OverwriteIfChanged case "if-newer": *c = OverwriteIfNewer case "never": @@ -70,6 +74,8 @@ func (c *OverwriteBehavior) String() string { switch *c { case OverwriteAlways: return "always" + case OverwriteIfChanged: + return "if-changed" case OverwriteIfNewer: return "if-newer" case OverwriteNever: @@ -87,10 +93,8 @@ func (c *OverwriteBehavior) Type() string { func NewRestorer(repo restic.Repository, sn *restic.Snapshot, opts Options) *Restorer { r := &Restorer{ repo: repo, - sparse: opts.Sparse, - progress: opts.Progress, - overwrite: opts.Overwrite, - fileList: make(map[string]struct{}), + opts: opts, + fileList: make(map[string]bool), Error: restorerAbortOnAllErrors, SelectFilter: func(string, string, *restic.Node) (bool, bool) { return true, true }, sn: sn, @@ -224,7 +228,7 @@ func (res *Restorer) restoreNodeTo(ctx context.Context, node *restic.Node, targe return err } - res.progress.AddProgress(location, 0, 0) + res.opts.Progress.AddProgress(location, 0, 0) return res.restoreNodeMetadataTo(node, target, location) } @@ -246,7 +250,7 @@ func (res *Restorer) restoreHardlinkAt(node *restic.Node, target, path, location return errors.WithStack(err) } - res.progress.AddProgress(location, 0, 0) + res.opts.Progress.AddProgress(location, 0, 0) // TODO investigate if hardlinks have separate metadata on any supported system return res.restoreNodeMetadataTo(node, path, location) @@ -265,16 +269,18 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { idx := NewHardlinkIndex[string]() filerestorer := newFileRestorer(dst, res.repo.LoadBlobsFromPack, res.repo.LookupBlob, - res.repo.Connections(), res.sparse, res.progress) + res.repo.Connections(), res.opts.Sparse, res.opts.Progress) filerestorer.Error = res.Error debug.Log("first pass for %q", dst) + var buf []byte + // first tree pass: create directories and collect all files to restore _, err = res.traverseTree(ctx, dst, string(filepath.Separator), *res.sn.Tree, treeVisitor{ enterDir: func(_ *restic.Node, target, location string) error { debug.Log("first pass, enterDir: mkdir %q, leaveDir should restore metadata", location) - res.progress.AddFile(0) + res.opts.Progress.AddFile(0) // create dir with default permissions // #leaveDir restores dir metadata after visiting all children return fs.MkdirAll(target, 0700) @@ -290,25 +296,30 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { } if node.Type != "file" { - res.progress.AddFile(0) + res.opts.Progress.AddFile(0) return nil } if node.Links > 1 { if idx.Has(node.Inode, node.DeviceID) { // a hardlinked file does not increase the restore size - res.progress.AddFile(0) + res.opts.Progress.AddFile(0) return nil } idx.Add(node.Inode, node.DeviceID, location) } - return res.withOverwriteCheck(node, target, false, func() error { - res.progress.AddFile(node.Size) - filerestorer.addFile(location, node.Content, int64(node.Size)) - res.trackFile(location) + buf, err = res.withOverwriteCheck(node, target, false, buf, func(updateMetadataOnly bool, matches *fileState) error { + if updateMetadataOnly { + res.opts.Progress.AddSkippedFile(node.Size) + } else { + res.opts.Progress.AddFile(node.Size) + filerestorer.addFile(location, node.Content, int64(node.Size), matches) + } + res.trackFile(location, updateMetadataOnly) return nil }) + return err }, }) if err != nil { @@ -327,18 +338,20 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { visitNode: func(node *restic.Node, target, location string) error { debug.Log("second pass, visitNode: restore node %q", location) if node.Type != "file" { - return res.withOverwriteCheck(node, target, false, func() error { + _, err := res.withOverwriteCheck(node, target, false, nil, func(_ bool, _ *fileState) error { return res.restoreNodeTo(ctx, node, target, location) }) + return err } if idx.Has(node.Inode, node.DeviceID) && idx.Value(node.Inode, node.DeviceID) != location { - return res.withOverwriteCheck(node, target, true, func() error { + _, err := res.withOverwriteCheck(node, target, true, nil, func(_ bool, _ *fileState) error { return res.restoreHardlinkAt(node, filerestorer.targetPath(idx.Value(node.Inode, node.DeviceID)), target, location) }) + return err } - if res.hasRestoredFile(location) { + if _, ok := res.hasRestoredFile(location); ok { return res.restoreNodeMetadataTo(node, target, location) } // don't touch skipped files @@ -347,7 +360,7 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { leaveDir: func(node *restic.Node, target, location string) error { err := res.restoreNodeMetadataTo(node, target, location) if err == nil { - res.progress.AddProgress(location, 0, 0) + res.opts.Progress.AddProgress(location, 0, 0) } return err }, @@ -355,32 +368,42 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) error { return err } -func (res *Restorer) trackFile(location string) { - res.fileList[location] = struct{}{} +func (res *Restorer) trackFile(location string, metadataOnly bool) { + res.fileList[location] = metadataOnly } -func (res *Restorer) hasRestoredFile(location string) bool { - _, ok := res.fileList[location] - return ok +func (res *Restorer) hasRestoredFile(location string) (metadataOnly bool, ok bool) { + metadataOnly, ok = res.fileList[location] + return metadataOnly, ok } -func (res *Restorer) withOverwriteCheck(node *restic.Node, target string, isHardlink bool, cb func() error) error { - overwrite, err := shouldOverwrite(res.overwrite, node, target) +func (res *Restorer) withOverwriteCheck(node *restic.Node, target string, isHardlink bool, buf []byte, cb func(updateMetadataOnly bool, matches *fileState) error) ([]byte, error) { + overwrite, err := shouldOverwrite(res.opts.Overwrite, node, target) if err != nil { - return err + return buf, err } else if !overwrite { size := node.Size if isHardlink { size = 0 } - res.progress.AddSkippedFile(size) - return nil + res.opts.Progress.AddSkippedFile(size) + return buf, nil } - return cb() + + var matches *fileState + updateMetadataOnly := false + if node.Type == "file" && !isHardlink { + // if a file fails to verify, then matches is nil which results in restoring from scratch + matches, buf, _ = res.verifyFile(target, node, false, res.opts.Overwrite == OverwriteIfChanged, buf) + // skip files that are already correct completely + updateMetadataOnly = !matches.NeedsRestore() + } + + return buf, cb(updateMetadataOnly, matches) } func shouldOverwrite(overwrite OverwriteBehavior, node *restic.Node, destination string) (bool, error) { - if overwrite == OverwriteAlways { + if overwrite == OverwriteAlways || overwrite == OverwriteIfChanged { return true, nil } @@ -433,7 +456,10 @@ func (res *Restorer) VerifyFiles(ctx context.Context, dst string) (int, error) { _, err := res.traverseTree(ctx, dst, string(filepath.Separator), *res.sn.Tree, treeVisitor{ visitNode: func(node *restic.Node, target, location string) error { - if node.Type != "file" || !res.hasRestoredFile(location) { + if node.Type != "file" { + return nil + } + if metadataOnly, ok := res.hasRestoredFile(location); !ok || metadataOnly { return nil } select { @@ -451,7 +477,7 @@ func (res *Restorer) VerifyFiles(ctx context.Context, dst string) (int, error) { g.Go(func() (err error) { var buf []byte for job := range work { - buf, err = res.verifyFile(job.path, job.node, buf) + _, buf, err = res.verifyFile(job.path, job.node, true, false, buf) if err != nil { err = res.Error(job.path, err) } @@ -467,34 +493,72 @@ func (res *Restorer) VerifyFiles(ctx context.Context, dst string) (int, error) { return int(nchecked), g.Wait() } +type fileState struct { + blobMatches []bool + sizeMatches bool +} + +func (s *fileState) NeedsRestore() bool { + if s == nil { + return true + } + if !s.sizeMatches { + return true + } + for _, match := range s.blobMatches { + if !match { + return true + } + } + return false +} + +func (s *fileState) HasMatchingBlob(i int) bool { + if s == nil || s.blobMatches == nil { + return false + } + return i < len(s.blobMatches) && s.blobMatches[i] +} + // Verify that the file target has the contents of node. // // buf and the first return value are scratch space, passed around for reuse. // Reusing buffers prevents the verifier goroutines allocating all of RAM and // flushing the filesystem cache (at least on Linux). -func (res *Restorer) verifyFile(target string, node *restic.Node, buf []byte) ([]byte, error) { - f, err := os.Open(target) +func (res *Restorer) verifyFile(target string, node *restic.Node, failFast bool, trustMtime bool, buf []byte) (*fileState, []byte, error) { + f, err := os.OpenFile(target, fs.O_RDONLY|fs.O_NOFOLLOW, 0) if err != nil { - return buf, err + return nil, buf, err } defer func() { _ = f.Close() }() fi, err := f.Stat() + sizeMatches := true switch { case err != nil: - return buf, err + return nil, buf, err + case !fi.Mode().IsRegular(): + return nil, buf, errors.Errorf("Expected %s to be a regular file", target) case int64(node.Size) != fi.Size(): - return buf, errors.Errorf("Invalid file size for %s: expected %d, got %d", - target, node.Size, fi.Size()) + if failFast { + return nil, buf, errors.Errorf("Invalid file size for %s: expected %d, got %d", + target, node.Size, fi.Size()) + } + sizeMatches = false } + if trustMtime && fi.ModTime().Equal(node.ModTime) && sizeMatches { + return &fileState{nil, sizeMatches}, buf, nil + } + + matches := make([]bool, len(node.Content)) var offset int64 - for _, blobID := range node.Content { + for i, blobID := range node.Content { length, found := res.repo.LookupBlobSize(restic.DataBlob, blobID) if !found { - return buf, errors.Errorf("Unable to fetch blob %s", blobID) + return nil, buf, errors.Errorf("Unable to fetch blob %s", blobID) } if length > uint(cap(buf)) { @@ -503,16 +567,21 @@ func (res *Restorer) verifyFile(target string, node *restic.Node, buf []byte) ([ buf = buf[:length] _, err = f.ReadAt(buf, offset) - if err != nil { - return buf, err + if err == io.EOF && !failFast { + sizeMatches = false + break } - if !blobID.Equal(restic.Hash(buf)) { - return buf, errors.Errorf( + if err != nil { + return nil, buf, err + } + matches[i] = blobID.Equal(restic.Hash(buf)) + if failFast && !matches[i] { + return nil, buf, errors.Errorf( "Unexpected content in %s, starting at offset %d", target, offset) } offset += int64(length) } - return buf, nil + return &fileState{matches, sizeMatches}, buf, nil } diff --git a/internal/restorer/restorer_test.go b/internal/restorer/restorer_test.go index 635c30ee6..25ce668db 100644 --- a/internal/restorer/restorer_test.go +++ b/internal/restorer/restorer_test.go @@ -10,6 +10,7 @@ import ( "path/filepath" "runtime" "strings" + "syscall" "testing" "time" @@ -894,6 +895,44 @@ func TestRestorerSparseFiles(t *testing.T) { len(zeros), blocks, 100*sparsity) } +func TestRestorerSparseOverwrite(t *testing.T) { + baseSnapshot := Snapshot{ + Nodes: map[string]Node{ + "foo": File{Data: "content: new\n"}, + }, + } + var zero [14]byte + sparseSnapshot := Snapshot{ + Nodes: map[string]Node{ + "foo": File{Data: string(zero[:])}, + }, + } + + repo := repository.TestRepository(t) + tempdir := filepath.Join(rtest.TempDir(t), "target") + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + // base snapshot + sn, id := saveSnapshot(t, repo, baseSnapshot, noopGetGenericAttributes) + t.Logf("base snapshot saved as %v", id.Str()) + + res := NewRestorer(repo, sn, Options{Sparse: true}) + err := res.RestoreTo(ctx, tempdir) + rtest.OK(t, err) + + // sparse snapshot + sn, id = saveSnapshot(t, repo, sparseSnapshot, noopGetGenericAttributes) + t.Logf("base snapshot saved as %v", id.Str()) + + res = NewRestorer(repo, sn, Options{Sparse: true, Overwrite: OverwriteAlways}) + err = res.RestoreTo(ctx, tempdir) + rtest.OK(t, err) + files, err := res.VerifyFiles(ctx, tempdir) + rtest.OK(t, err) + rtest.Equals(t, 1, files, "unexpected number of verified files") +} + func TestRestorerOverwriteBehavior(t *testing.T) { baseTime := time.Now() baseSnapshot := Snapshot{ @@ -929,6 +968,13 @@ func TestRestorerOverwriteBehavior(t *testing.T) { "dirtest/file": "content: file2\n", }, }, + { + Overwrite: OverwriteIfChanged, + Files: map[string]string{ + "foo": "content: new\n", + "dirtest/file": "content: file2\n", + }, + }, { Overwrite: OverwriteIfNewer, Files: map[string]string{ @@ -982,3 +1028,88 @@ func TestRestorerOverwriteBehavior(t *testing.T) { }) } } + +func TestRestoreModified(t *testing.T) { + // overwrite files between snapshots and also change their filesize + snapshots := []Snapshot{ + { + Nodes: map[string]Node{ + "foo": File{Data: "content: foo\n", ModTime: time.Now()}, + "bar": File{Data: "content: a\n", ModTime: time.Now()}, + }, + }, + { + Nodes: map[string]Node{ + "foo": File{Data: "content: a\n", ModTime: time.Now()}, + "bar": File{Data: "content: bar\n", ModTime: time.Now()}, + }, + }, + } + + repo := repository.TestRepository(t) + tempdir := filepath.Join(rtest.TempDir(t), "target") + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + for _, snapshot := range snapshots { + sn, id := saveSnapshot(t, repo, snapshot, noopGetGenericAttributes) + t.Logf("snapshot saved as %v", id.Str()) + + res := NewRestorer(repo, sn, Options{Overwrite: OverwriteIfChanged}) + rtest.OK(t, res.RestoreTo(ctx, tempdir)) + n, err := res.VerifyFiles(ctx, tempdir) + rtest.OK(t, err) + rtest.Equals(t, 2, n, "unexpected number of verified files") + } +} + +func TestRestoreIfChanged(t *testing.T) { + origData := "content: foo\n" + modData := "content: bar\n" + rtest.Equals(t, len(modData), len(origData), "broken testcase") + snapshot := Snapshot{ + Nodes: map[string]Node{ + "foo": File{Data: origData, ModTime: time.Now()}, + }, + } + + repo := repository.TestRepository(t) + tempdir := filepath.Join(rtest.TempDir(t), "target") + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + sn, id := saveSnapshot(t, repo, snapshot, noopGetGenericAttributes) + t.Logf("snapshot saved as %v", id.Str()) + + res := NewRestorer(repo, sn, Options{}) + rtest.OK(t, res.RestoreTo(ctx, tempdir)) + + // modify file but maintain size and timestamp + path := filepath.Join(tempdir, "foo") + f, err := os.OpenFile(path, os.O_RDWR, 0) + rtest.OK(t, err) + fi, err := f.Stat() + rtest.OK(t, err) + _, err = f.Write([]byte(modData)) + rtest.OK(t, err) + rtest.OK(t, f.Close()) + var utimes = [...]syscall.Timespec{ + syscall.NsecToTimespec(fi.ModTime().UnixNano()), + syscall.NsecToTimespec(fi.ModTime().UnixNano()), + } + rtest.OK(t, syscall.UtimesNano(path, utimes[:])) + + for _, overwrite := range []OverwriteBehavior{OverwriteIfChanged, OverwriteAlways} { + res = NewRestorer(repo, sn, Options{Overwrite: overwrite}) + rtest.OK(t, res.RestoreTo(ctx, tempdir)) + data, err := os.ReadFile(path) + rtest.OK(t, err) + if overwrite == OverwriteAlways { + // restore should notice the changed file content + rtest.Equals(t, origData, string(data), "expected original file content") + } else { + // restore should not have noticed the changed file content + rtest.Equals(t, modData, string(data), "expeced modified file content") + } + } +} diff --git a/internal/restorer/restorer_unix_test.go b/internal/restorer/restorer_unix_test.go index 97d2dd07d..9523440cf 100644 --- a/internal/restorer/restorer_unix_test.go +++ b/internal/restorer/restorer_unix_test.go @@ -5,6 +5,7 @@ package restorer import ( "context" + "io/fs" "os" "path/filepath" "syscall" @@ -118,3 +119,34 @@ func TestRestorerProgressBar(t *testing.T) { AllBytesSkipped: 0, }, mock.s) } + +func TestRestorePermissions(t *testing.T) { + snapshot := Snapshot{ + Nodes: map[string]Node{ + "foo": File{Data: "content: foo\n", Mode: 0o600, ModTime: time.Now()}, + }, + } + + repo := repository.TestRepository(t) + tempdir := filepath.Join(rtest.TempDir(t), "target") + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + sn, id := saveSnapshot(t, repo, snapshot, noopGetGenericAttributes) + t.Logf("snapshot saved as %v", id.Str()) + + res := NewRestorer(repo, sn, Options{}) + rtest.OK(t, res.RestoreTo(ctx, tempdir)) + + for _, overwrite := range []OverwriteBehavior{OverwriteIfChanged, OverwriteAlways} { + // tamper with permissions + path := filepath.Join(tempdir, "foo") + rtest.OK(t, os.Chmod(path, 0o700)) + + res = NewRestorer(repo, sn, Options{Overwrite: overwrite}) + rtest.OK(t, res.RestoreTo(ctx, tempdir)) + fi, err := os.Stat(path) + rtest.OK(t, err) + rtest.Equals(t, fs.FileMode(0o600), fi.Mode().Perm(), "unexpected permissions") + } +}