diff options
| author | mo khan <mo@mokhan.ca> | 2025-05-14 13:18:54 -0600 |
|---|---|---|
| committer | mo khan <mo@mokhan.ca> | 2025-05-14 13:18:54 -0600 |
| commit | 4b2d609a0efcc1d9b2f1a08f954d067ad1d9cd1e (patch) | |
| tree | 0afacf9217b0569130da6b97d4197331681bf119 /vendor/github.com/moby/go-archive/changes.go | |
| parent | ab373d1fe698cd3f53258c09bc8515d88a6d0b9e (diff) | |
test: use playwright to test out an OIDC login
Diffstat (limited to 'vendor/github.com/moby/go-archive/changes.go')
| -rw-r--r-- | vendor/github.com/moby/go-archive/changes.go | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/vendor/github.com/moby/go-archive/changes.go b/vendor/github.com/moby/go-archive/changes.go new file mode 100644 index 0000000..02a0372 --- /dev/null +++ b/vendor/github.com/moby/go-archive/changes.go @@ -0,0 +1,430 @@ +package archive + +import ( + "archive/tar" + "bytes" + "context" + "fmt" + "io" + "io/fs" + "os" + "path/filepath" + "sort" + "strings" + "time" + + "github.com/containerd/log" + "github.com/moby/sys/user" +) + +// ChangeType represents the change type. +type ChangeType int + +const ( + ChangeModify = 0 // ChangeModify represents the modify operation. + ChangeAdd = 1 // ChangeAdd represents the add operation. + ChangeDelete = 2 // ChangeDelete represents the delete operation. +) + +func (c ChangeType) String() string { + switch c { + case ChangeModify: + return "C" + case ChangeAdd: + return "A" + case ChangeDelete: + return "D" + } + return "" +} + +// Change represents a change, it wraps the change type and path. +// It describes changes of the files in the path respect to the +// parent layers. The change could be modify, add, delete. +// This is used for layer diff. +type Change struct { + Path string + Kind ChangeType +} + +func (change *Change) String() string { + return fmt.Sprintf("%s %s", change.Kind, change.Path) +} + +// for sort.Sort +type changesByPath []Change + +func (c changesByPath) Less(i, j int) bool { return c[i].Path < c[j].Path } +func (c changesByPath) Len() int { return len(c) } +func (c changesByPath) Swap(i, j int) { c[j], c[i] = c[i], c[j] } + +// Gnu tar doesn't have sub-second mtime precision. The go tar +// writer (1.10+) does when using PAX format, but we round times to seconds +// to ensure archives have the same hashes for backwards compatibility. +// See https://github.com/moby/moby/pull/35739/commits/fb170206ba12752214630b269a40ac7be6115ed4. +// +// Non-sub-second is problematic when we apply changes via tar +// files. We handle this by comparing for exact times, *or* same +// second count and either a or b having exactly 0 nanoseconds +func sameFsTime(a, b time.Time) bool { + return a.Equal(b) || + (a.Unix() == b.Unix() && + (a.Nanosecond() == 0 || b.Nanosecond() == 0)) +} + +// Changes walks the path rw and determines changes for the files in the path, +// with respect to the parent layers +func Changes(layers []string, rw string) ([]Change, error) { + return collectChanges(layers, rw, aufsDeletedFile, aufsMetadataSkip) +} + +func aufsMetadataSkip(path string) (skip bool, err error) { + skip, err = filepath.Match(string(os.PathSeparator)+WhiteoutMetaPrefix+"*", path) + if err != nil { + skip = true + } + return skip, err +} + +func aufsDeletedFile(root, path string, fi os.FileInfo) (string, error) { + f := filepath.Base(path) + + // If there is a whiteout, then the file was removed + if strings.HasPrefix(f, WhiteoutPrefix) { + originalFile := f[len(WhiteoutPrefix):] + return filepath.Join(filepath.Dir(path), originalFile), nil + } + + return "", nil +} + +type ( + skipChange func(string) (bool, error) + deleteChange func(string, string, os.FileInfo) (string, error) +) + +func collectChanges(layers []string, rw string, dc deleteChange, sc skipChange) ([]Change, error) { + var ( + changes []Change + changedDirs = make(map[string]struct{}) + ) + + err := filepath.Walk(rw, func(path string, f os.FileInfo, err error) error { + if err != nil { + return err + } + + // Rebase path + path, err = filepath.Rel(rw, path) + if err != nil { + return err + } + + // As this runs on the daemon side, file paths are OS specific. + path = filepath.Join(string(os.PathSeparator), path) + + // Skip root + if path == string(os.PathSeparator) { + return nil + } + + if sc != nil { + if skip, err := sc(path); skip { + return err + } + } + + change := Change{ + Path: path, + } + + deletedFile, err := dc(rw, path, f) + if err != nil { + return err + } + + // Find out what kind of modification happened + if deletedFile != "" { + change.Path = deletedFile + change.Kind = ChangeDelete + } else { + // Otherwise, the file was added + change.Kind = ChangeAdd + + // ...Unless it already existed in a top layer, in which case, it's a modification + for _, layer := range layers { + stat, err := os.Stat(filepath.Join(layer, path)) + if err != nil && !os.IsNotExist(err) { + return err + } + if err == nil { + // The file existed in the top layer, so that's a modification + + // However, if it's a directory, maybe it wasn't actually modified. + // If you modify /foo/bar/baz, then /foo will be part of the changed files only because it's the parent of bar + if stat.IsDir() && f.IsDir() { + if f.Size() == stat.Size() && f.Mode() == stat.Mode() && sameFsTime(f.ModTime(), stat.ModTime()) { + // Both directories are the same, don't record the change + return nil + } + } + change.Kind = ChangeModify + break + } + } + } + + // If /foo/bar/file.txt is modified, then /foo/bar must be part of the changed files. + // This block is here to ensure the change is recorded even if the + // modify time, mode and size of the parent directory in the rw and ro layers are all equal. + // Check https://github.com/docker/docker/pull/13590 for details. + if f.IsDir() { + changedDirs[path] = struct{}{} + } + if change.Kind == ChangeAdd || change.Kind == ChangeDelete { + parent := filepath.Dir(path) + if _, ok := changedDirs[parent]; !ok && parent != "/" { + changes = append(changes, Change{Path: parent, Kind: ChangeModify}) + changedDirs[parent] = struct{}{} + } + } + + // Record change + changes = append(changes, change) + return nil + }) + if err != nil && !os.IsNotExist(err) { + return nil, err + } + return changes, nil +} + +// FileInfo describes the information of a file. +type FileInfo struct { + parent *FileInfo + name string + stat fs.FileInfo + children map[string]*FileInfo + capability []byte + added bool +} + +// LookUp looks up the file information of a file. +func (info *FileInfo) LookUp(path string) *FileInfo { + // As this runs on the daemon side, file paths are OS specific. + parent := info + if path == string(os.PathSeparator) { + return info + } + + pathElements := strings.Split(path, string(os.PathSeparator)) + for _, elem := range pathElements { + if elem != "" { + child := parent.children[elem] + if child == nil { + return nil + } + parent = child + } + } + return parent +} + +func (info *FileInfo) path() string { + if info.parent == nil { + // As this runs on the daemon side, file paths are OS specific. + return string(os.PathSeparator) + } + return filepath.Join(info.parent.path(), info.name) +} + +func (info *FileInfo) addChanges(oldInfo *FileInfo, changes *[]Change) { + sizeAtEntry := len(*changes) + + if oldInfo == nil { + // add + change := Change{ + Path: info.path(), + Kind: ChangeAdd, + } + *changes = append(*changes, change) + info.added = true + } + + // We make a copy so we can modify it to detect additions + // also, we only recurse on the old dir if the new info is a directory + // otherwise any previous delete/change is considered recursive + oldChildren := make(map[string]*FileInfo) + if oldInfo != nil && info.isDir() { + for k, v := range oldInfo.children { + oldChildren[k] = v + } + } + + for name, newChild := range info.children { + oldChild := oldChildren[name] + if oldChild != nil { + // change? + oldStat := oldChild.stat + newStat := newChild.stat + // Note: We can't compare inode or ctime or blocksize here, because these change + // when copying a file into a container. However, that is not generally a problem + // because any content change will change mtime, and any status change should + // be visible when actually comparing the stat fields. The only time this + // breaks down is if some code intentionally hides a change by setting + // back mtime + if statDifferent(oldStat, newStat) || + !bytes.Equal(oldChild.capability, newChild.capability) { + change := Change{ + Path: newChild.path(), + Kind: ChangeModify, + } + *changes = append(*changes, change) + newChild.added = true + } + + // Remove from copy so we can detect deletions + delete(oldChildren, name) + } + + newChild.addChanges(oldChild, changes) + } + for _, oldChild := range oldChildren { + // delete + change := Change{ + Path: oldChild.path(), + Kind: ChangeDelete, + } + *changes = append(*changes, change) + } + + // If there were changes inside this directory, we need to add it, even if the directory + // itself wasn't changed. This is needed to properly save and restore filesystem permissions. + // As this runs on the daemon side, file paths are OS specific. + if len(*changes) > sizeAtEntry && info.isDir() && !info.added && info.path() != string(os.PathSeparator) { + change := Change{ + Path: info.path(), + Kind: ChangeModify, + } + // Let's insert the directory entry before the recently added entries located inside this dir + *changes = append(*changes, change) // just to resize the slice, will be overwritten + copy((*changes)[sizeAtEntry+1:], (*changes)[sizeAtEntry:]) + (*changes)[sizeAtEntry] = change + } +} + +// Changes add changes to file information. +func (info *FileInfo) Changes(oldInfo *FileInfo) []Change { + var changes []Change + + info.addChanges(oldInfo, &changes) + + return changes +} + +func newRootFileInfo() *FileInfo { + // As this runs on the daemon side, file paths are OS specific. + root := &FileInfo{ + name: string(os.PathSeparator), + children: make(map[string]*FileInfo), + } + return root +} + +// ChangesDirs compares two directories and generates an array of Change objects describing the changes. +// If oldDir is "", then all files in newDir will be Add-Changes. +func ChangesDirs(newDir, oldDir string) ([]Change, error) { + var oldRoot, newRoot *FileInfo + if oldDir == "" { + emptyDir, err := os.MkdirTemp("", "empty") + if err != nil { + return nil, err + } + defer os.Remove(emptyDir) + oldDir = emptyDir + } + oldRoot, newRoot, err := collectFileInfoForChanges(oldDir, newDir) + if err != nil { + return nil, err + } + + return newRoot.Changes(oldRoot), nil +} + +// ChangesSize calculates the size in bytes of the provided changes, based on newDir. +func ChangesSize(newDir string, changes []Change) int64 { + var ( + size int64 + sf = make(map[uint64]struct{}) + ) + for _, change := range changes { + if change.Kind == ChangeModify || change.Kind == ChangeAdd { + file := filepath.Join(newDir, change.Path) + fileInfo, err := os.Lstat(file) + if err != nil { + log.G(context.TODO()).Errorf("Can not stat %q: %s", file, err) + continue + } + + if fileInfo != nil && !fileInfo.IsDir() { + if hasHardlinks(fileInfo) { + inode := getIno(fileInfo) + if _, ok := sf[inode]; !ok { + size += fileInfo.Size() + sf[inode] = struct{}{} + } + } else { + size += fileInfo.Size() + } + } + } + } + return size +} + +// ExportChanges produces an Archive from the provided changes, relative to dir. +func ExportChanges(dir string, changes []Change, idMap user.IdentityMapping) (io.ReadCloser, error) { + reader, writer := io.Pipe() + go func() { + ta := newTarAppender(idMap, writer, nil) + + sort.Sort(changesByPath(changes)) + + // In general we log errors here but ignore them because + // during e.g. a diff operation the container can continue + // mutating the filesystem and we can see transient errors + // from this + for _, change := range changes { + if change.Kind == ChangeDelete { + whiteOutDir := filepath.Dir(change.Path) + whiteOutBase := filepath.Base(change.Path) + whiteOut := filepath.Join(whiteOutDir, WhiteoutPrefix+whiteOutBase) + timestamp := time.Now() + hdr := &tar.Header{ + Name: whiteOut[1:], + Size: 0, + ModTime: timestamp, + AccessTime: timestamp, + ChangeTime: timestamp, + } + if err := ta.TarWriter.WriteHeader(hdr); err != nil { + log.G(context.TODO()).Debugf("Can't write whiteout header: %s", err) + } + } else { + path := filepath.Join(dir, change.Path) + if err := ta.addTarFile(path, change.Path[1:]); err != nil { + log.G(context.TODO()).Debugf("Can't add file %s to tar: %s", path, err) + } + } + } + + // Make sure to check the error on Close. + if err := ta.TarWriter.Close(); err != nil { + log.G(context.TODO()).Debugf("Can't close layer: %s", err) + } + if err := writer.Close(); err != nil { + log.G(context.TODO()).Debugf("failed close Changes writer: %s", err) + } + }() + return reader, nil +} |
