dock: add trash CLI, refine implementation

core/internal/trash/trash.go

@@ -0,0 +1,455 @@
+// Package trash implements the FreeDesktop.org Trash specification 1.0.
+// See: https://specifications.freedesktop.org/trash-spec/trashspec-1.0.html
+package trash
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+	"time"
+)
+
+const trashInfoExt = ".trashinfo"
+
+type Entry struct {
+	Name         string `json:"name"`
+	OriginalPath string `json:"originalPath"`
+	DeletionDate string `json:"deletionDate"`
+	TrashDir     string `json:"trashDir"`
+	FilesPath    string `json:"filesPath"`
+	InfoPath     string `json:"infoPath"`
+	Size         int64  `json:"size"`
+	IsDir        bool   `json:"isDir"`
+}
+
+func homeTrashDir() (string, error) {
+	xdg := os.Getenv("XDG_DATA_HOME")
+	if xdg == "" {
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return "", err
+		}
+		xdg = filepath.Join(home, ".local", "share")
+	}
+	return filepath.Join(xdg, "Trash"), nil
+}
+
+func ensureTrashDirs(trashDir string) error {
+	if err := os.MkdirAll(filepath.Join(trashDir, "files"), 0o700); err != nil {
+		return err
+	}
+	return os.MkdirAll(filepath.Join(trashDir, "info"), 0o700)
+}
+
+func fsDevice(path string) (uint64, error) {
+	var st syscall.Stat_t
+	if err := syscall.Lstat(path, &st); err != nil {
+		return 0, err
+	}
+	return uint64(st.Dev), nil
+}
+
+func fsDeviceWalkUp(start string) (uint64, error) {
+	cur := start
+	for {
+		if dev, err := fsDevice(cur); err == nil {
+			return dev, nil
+		}
+		parent := filepath.Dir(cur)
+		if parent == cur {
+			return 0, fmt.Errorf("no existing ancestor for %s", start)
+		}
+		cur = parent
+	}
+}
+
+func findTopDir(path string) (string, error) {
+	abs, err := filepath.Abs(path)
+	if err != nil {
+		return "", err
+	}
+	dev, err := fsDevice(abs)
+	if err != nil {
+		return "", err
+	}
+	cur := abs
+	for {
+		parent := filepath.Dir(cur)
+		if parent == cur {
+			return cur, nil
+		}
+		pdev, err := fsDevice(parent)
+		if err != nil {
+			return cur, nil
+		}
+		if pdev != dev {
+			return cur, nil
+		}
+		cur = parent
+	}
+}
+
+// isValidSharedTrash enforces the spec's checks on $topdir/.Trash:
+// must exist, must be a directory, must not be a symlink, must have sticky bit.
+func isValidSharedTrash(p string) bool {
+	info, err := os.Lstat(p)
+	if err != nil {
+		return false
+	}
+	if info.Mode()&os.ModeSymlink != 0 {
+		return false
+	}
+	if !info.IsDir() {
+		return false
+	}
+	return info.Mode()&os.ModeSticky != 0
+}
+
+// trashDirForPath chooses the correct trash dir per spec and returns the value
+// to store in the .trashinfo Path field (absolute for home, relative-to-topdir
+// for per-mountpoint trash).
+func trashDirForPath(absPath string) (trashDir string, storedPath string, err error) {
+	home, err := homeTrashDir()
+	if err != nil {
+		return "", "", err
+	}
+
+	pathDev, err := fsDevice(absPath)
+	if err != nil {
+		return "", "", err
+	}
+	homeDev, err := fsDeviceWalkUp(home)
+	if err != nil {
+		return "", "", err
+	}
+
+	if pathDev == homeDev {
+		return home, absPath, nil
+	}
+
+	topDir, err := findTopDir(absPath)
+	if err != nil {
+		return "", "", err
+	}
+
+	uid := strconv.Itoa(os.Getuid())
+	stored, rerr := filepath.Rel(topDir, absPath)
+	if rerr != nil || strings.HasPrefix(stored, "..") {
+		stored = absPath
+	}
+
+	shared := filepath.Join(topDir, ".Trash")
+	if isValidSharedTrash(shared) {
+		return filepath.Join(shared, uid), stored, nil
+	}
+	return filepath.Join(topDir, ".Trash-"+uid), stored, nil
+}
+
+// uniqueName returns a basename in trashDir that does not collide with an
+// existing entry in either files/ or info/.
+func uniqueName(trashDir, basename string) (string, error) {
+	filesDir := filepath.Join(trashDir, "files")
+	infoDir := filepath.Join(trashDir, "info")
+	if !exists(filepath.Join(filesDir, basename)) && !exists(filepath.Join(infoDir, basename+trashInfoExt)) {
+		return basename, nil
+	}
+	ext := filepath.Ext(basename)
+	stem := strings.TrimSuffix(basename, ext)
+	for i := 2; i < 100000; i++ {
+		candidate := fmt.Sprintf("%s.%d%s", stem, i, ext)
+		if !exists(filepath.Join(filesDir, candidate)) && !exists(filepath.Join(infoDir, candidate+trashInfoExt)) {
+			return candidate, nil
+		}
+	}
+	return "", errors.New("could not find unique trash name")
+}
+
+func exists(p string) bool {
+	_, err := os.Lstat(p)
+	return err == nil
+}
+
+// pathEncode percent-escapes a POSIX path per RFC 2396, preserving "/".
+func pathEncode(p string) string {
+	parts := strings.Split(p, "/")
+	for i, seg := range parts {
+		parts[i] = url.PathEscape(seg)
+	}
+	return strings.Join(parts, "/")
+}
+
+func pathDecode(p string) string {
+	if d, err := url.PathUnescape(p); err == nil {
+		return d
+	}
+	return p
+}
+
+func writeTrashInfo(infoPath, storedPath string, when time.Time) error {
+	body := "[Trash Info]\nPath=" + pathEncode(storedPath) +
+		"\nDeletionDate=" + when.Format("2006-01-02T15:04:05") + "\n"
+	f, err := os.OpenFile(infoPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0o600)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, err = f.WriteString(body)
+	return err
+}
+
+// Put trashes a single file or directory.
+func Put(path string) (Entry, error) {
+	abs, err := filepath.Abs(path)
+	if err != nil {
+		return Entry{}, err
+	}
+	info, err := os.Lstat(abs)
+	if err != nil {
+		return Entry{}, err
+	}
+
+	trashDir, storedPath, err := trashDirForPath(abs)
+	if err != nil {
+		return Entry{}, err
+	}
+	if err := ensureTrashDirs(trashDir); err != nil {
+		return Entry{}, fmt.Errorf("create trash dir %s: %w", trashDir, err)
+	}
+
+	name, err := uniqueName(trashDir, filepath.Base(abs))
+	if err != nil {
+		return Entry{}, err
+	}
+
+	infoPath := filepath.Join(trashDir, "info", name+trashInfoExt)
+	when := time.Now()
+	if err := writeTrashInfo(infoPath, storedPath, when); err != nil {
+		return Entry{}, err
+	}
+
+	target := filepath.Join(trashDir, "files", name)
+	if err := os.Rename(abs, target); err != nil {
+		os.Remove(infoPath)
+		return Entry{}, err
+	}
+
+	return Entry{
+		Name:         name,
+		OriginalPath: storedPath,
+		DeletionDate: when.Format("2006-01-02T15:04:05"),
+		TrashDir:     trashDir,
+		FilesPath:    target,
+		InfoPath:     infoPath,
+		Size:         info.Size(),
+		IsDir:        info.IsDir(),
+	}, nil
+}
+
+// allTrashDirs returns the home trash plus every per-mountpoint trash dir
+// that exists (and passes the spec's safety checks for $topdir/.Trash).
+func allTrashDirs() []string {
+	var dirs []string
+	if h, err := homeTrashDir(); err == nil {
+		dirs = append(dirs, h)
+	}
+
+	uid := strconv.Itoa(os.Getuid())
+	for _, mount := range readMountPoints() {
+		shared := filepath.Join(mount, ".Trash")
+		if isValidSharedTrash(shared) {
+			candidate := filepath.Join(shared, uid)
+			if info, err := os.Stat(candidate); err == nil && info.IsDir() {
+				dirs = append(dirs, candidate)
+			}
+		}
+		candidate := filepath.Join(mount, ".Trash-"+uid)
+		if info, err := os.Lstat(candidate); err == nil && info.IsDir() && info.Mode()&os.ModeSymlink == 0 {
+			dirs = append(dirs, candidate)
+		}
+	}
+	return dirs
+}
+
+// readMountPoints returns user-visible mount points from /proc/self/mountinfo,
+// skipping pseudo and system filesystems.
+func readMountPoints() []string {
+	data, err := os.ReadFile("/proc/self/mountinfo")
+	if err != nil {
+		return nil
+	}
+	skipPrefixes := []string{"/proc", "/sys", "/dev"}
+	var out []string
+	seen := map[string]bool{}
+	for line := range strings.SplitSeq(string(data), "\n") {
+		fields := strings.Fields(line)
+		if len(fields) < 5 {
+			continue
+		}
+		mp := fields[4]
+		if mp == "/" {
+			continue
+		}
+		skip := false
+		for _, p := range skipPrefixes {
+			if mp == p || strings.HasPrefix(mp, p+"/") {
+				skip = true
+				break
+			}
+		}
+		if skip || seen[mp] {
+			continue
+		}
+		seen[mp] = true
+		out = append(out, mp)
+	}
+	return out
+}
+
+func List() ([]Entry, error) {
+	var entries []Entry
+	for _, d := range allTrashDirs() {
+		es, _ := listOne(d)
+		entries = append(entries, es...)
+	}
+	return entries, nil
+}
+
+func listOne(trashDir string) ([]Entry, error) {
+	infoDir := filepath.Join(trashDir, "info")
+	filesDir := filepath.Join(trashDir, "files")
+	dir, err := os.ReadDir(infoDir)
+	if err != nil {
+		return nil, err
+	}
+	var entries []Entry
+	for _, ent := range dir {
+		if !strings.HasSuffix(ent.Name(), trashInfoExt) {
+			continue
+		}
+		name := strings.TrimSuffix(ent.Name(), trashInfoExt)
+		infoPath := filepath.Join(infoDir, ent.Name())
+		filesPath := filepath.Join(filesDir, name)
+
+		body, err := os.ReadFile(infoPath)
+		if err != nil {
+			continue
+		}
+
+		e := Entry{Name: name, TrashDir: trashDir, InfoPath: infoPath, FilesPath: filesPath}
+		for line := range strings.SplitSeq(string(body), "\n") {
+			if v, ok := strings.CutPrefix(line, "Path="); ok {
+				e.OriginalPath = pathDecode(v)
+				continue
+			}
+			if v, ok := strings.CutPrefix(line, "DeletionDate="); ok {
+				e.DeletionDate = v
+			}
+		}
+		if info, err := os.Lstat(filesPath); err == nil {
+			e.Size = info.Size()
+			e.IsDir = info.IsDir()
+		}
+		entries = append(entries, e)
+	}
+	return entries, nil
+}
+
+func Count() (int, error) {
+	n := 0
+	for _, d := range allTrashDirs() {
+		ents, err := os.ReadDir(filepath.Join(d, "info"))
+		if err != nil {
+			continue
+		}
+		for _, e := range ents {
+			if strings.HasSuffix(e.Name(), trashInfoExt) {
+				n++
+			}
+		}
+	}
+	return n, nil
+}
+
+func Empty() error {
+	var firstErr error
+	for _, d := range allTrashDirs() {
+		if err := emptyOne(d); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	return firstErr
+}
+
+func emptyOne(trashDir string) error {
+	var firstErr error
+	for _, sub := range []string{"files", "info"} {
+		path := filepath.Join(trashDir, sub)
+		ents, err := os.ReadDir(path)
+		if err != nil {
+			continue
+		}
+		for _, e := range ents {
+			if err := os.RemoveAll(filepath.Join(path, e.Name())); err != nil && firstErr == nil {
+				firstErr = err
+			}
+		}
+	}
+	os.Remove(filepath.Join(trashDir, "directorysizes"))
+	return firstErr
+}
+
+// Restore returns a trashed item to its original location.
+func Restore(name, trashDir string) error {
+	if trashDir == "" {
+		h, err := homeTrashDir()
+		if err != nil {
+			return err
+		}
+		trashDir = h
+	}
+
+	infoPath := filepath.Join(trashDir, "info", name+trashInfoExt)
+	filesPath := filepath.Join(trashDir, "files", name)
+
+	body, err := os.ReadFile(infoPath)
+	if err != nil {
+		return err
+	}
+
+	var stored string
+	for line := range strings.SplitSeq(string(body), "\n") {
+		if v, ok := strings.CutPrefix(line, "Path="); ok {
+			stored = pathDecode(v)
+			break
+		}
+	}
+	if stored == "" {
+		return errors.New("invalid .trashinfo: missing Path")
+	}
+
+	target := stored
+	if !filepath.IsAbs(stored) {
+		topDir := filepath.Dir(trashDir)
+		if filepath.Base(topDir) == ".Trash" {
+			topDir = filepath.Dir(topDir)
+		}
+		target = filepath.Join(topDir, stored)
+	}
+
+	if exists(target) {
+		return fmt.Errorf("restore target already exists: %s", target)
+	}
+	if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil {
+		return err
+	}
+	if err := os.Rename(filesPath, target); err != nil {
+		return err
+	}
+	os.Remove(infoPath)
+	return nil
+}

core/internal/trash/trash_test.go

@@ -0,0 +1,315 @@
+package trash
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func setupHomeTrash(t *testing.T) (homeRoot string, trashDir string) {
+	t.Helper()
+	homeRoot = t.TempDir()
+	xdg := filepath.Join(homeRoot, ".local", "share")
+	if err := os.MkdirAll(xdg, 0o700); err != nil {
+		t.Fatalf("mkdir xdg: %v", err)
+	}
+	t.Setenv("XDG_DATA_HOME", xdg)
+	t.Setenv("HOME", homeRoot)
+	trashDir = filepath.Join(xdg, "Trash")
+	return homeRoot, trashDir
+}
+
+func writeFile(t *testing.T, path, content string) {
+	t.Helper()
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+		t.Fatalf("mkdir: %v", err)
+	}
+	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
+		t.Fatalf("write %s: %v", path, err)
+	}
+}
+
+func TestPutHomeTrashAbsolutePath(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	src := filepath.Join(homeRoot, "doc.txt")
+	writeFile(t, src, "hi")
+
+	entry, err := Put(src)
+	if err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	if entry.Name != "doc.txt" {
+		t.Errorf("name = %q, want doc.txt", entry.Name)
+	}
+	if entry.OriginalPath != src {
+		t.Errorf("originalPath = %q, want %q", entry.OriginalPath, src)
+	}
+	if entry.TrashDir != trashDir {
+		t.Errorf("trashDir = %q, want %q", entry.TrashDir, trashDir)
+	}
+	if _, err := os.Stat(src); !os.IsNotExist(err) {
+		t.Errorf("source still exists: %v", err)
+	}
+
+	body, err := os.ReadFile(filepath.Join(trashDir, "info", "doc.txt.trashinfo"))
+	if err != nil {
+		t.Fatalf("read trashinfo: %v", err)
+	}
+	if !strings.HasPrefix(string(body), "[Trash Info]\n") {
+		t.Errorf("trashinfo missing header: %q", body)
+	}
+	if !strings.Contains(string(body), "Path="+src+"\n") {
+		t.Errorf("Path key missing or wrong: %q", body)
+	}
+	if !strings.Contains(string(body), "DeletionDate=") {
+		t.Errorf("DeletionDate missing: %q", body)
+	}
+}
+
+func TestPutPercentEncodesPath(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	name := "spaces & %.txt"
+	src := filepath.Join(homeRoot, name)
+	writeFile(t, src, "x")
+
+	if _, err := Put(src); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	body, err := os.ReadFile(filepath.Join(trashDir, "info", name+".trashinfo"))
+	if err != nil {
+		t.Fatalf("read: %v", err)
+	}
+	want := "Path=" + filepath.Dir(src) + "/spaces%20&%20%25.txt"
+	if !strings.Contains(string(body), want) {
+		t.Errorf("expected %q in %q", want, body)
+	}
+}
+
+func TestPutCollisionGetsUniqueName(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	for i := range 3 {
+		src := filepath.Join(homeRoot, "dup.txt")
+		writeFile(t, src, "x")
+		if _, err := Put(src); err != nil {
+			t.Fatalf("Put #%d: %v", i, err)
+		}
+	}
+
+	want := []string{"dup.txt", "dup.2.txt", "dup.3.txt"}
+	for _, n := range want {
+		if _, err := os.Stat(filepath.Join(trashDir, "files", n)); err != nil {
+			t.Errorf("expected %s in trash: %v", n, err)
+		}
+		if _, err := os.Stat(filepath.Join(trashDir, "info", n+".trashinfo")); err != nil {
+			t.Errorf("expected %s.trashinfo: %v", n, err)
+		}
+	}
+}
+
+func TestListAndCount(t *testing.T) {
+	homeRoot, _ := setupHomeTrash(t)
+
+	if n, _ := Count(); n != 0 {
+		t.Errorf("initial count = %d, want 0", n)
+	}
+	entries, _ := List()
+	if len(entries) != 0 {
+		t.Errorf("initial list len = %d, want 0", len(entries))
+	}
+
+	for _, n := range []string{"a.txt", "b.txt", "c.log"} {
+		src := filepath.Join(homeRoot, n)
+		writeFile(t, src, n)
+		if _, err := Put(src); err != nil {
+			t.Fatalf("Put %s: %v", n, err)
+		}
+	}
+
+	got, _ := Count()
+	if got != 3 {
+		t.Errorf("count = %d, want 3", got)
+	}
+	entries, _ = List()
+	if len(entries) != 3 {
+		t.Errorf("list len = %d, want 3", len(entries))
+	}
+	for _, e := range entries {
+		if e.OriginalPath == "" {
+			t.Errorf("entry %s: empty OriginalPath", e.Name)
+		}
+		if _, err := time.Parse("2006-01-02T15:04:05", e.DeletionDate); err != nil {
+			t.Errorf("entry %s: bad DeletionDate %q: %v", e.Name, e.DeletionDate, err)
+		}
+	}
+}
+
+func TestEmptyClearsAll(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	for _, n := range []string{"x", "y", "z"} {
+		src := filepath.Join(homeRoot, n)
+		writeFile(t, src, n)
+		if _, err := Put(src); err != nil {
+			t.Fatalf("Put: %v", err)
+		}
+	}
+	if n, _ := Count(); n != 3 {
+		t.Fatalf("pre-empty count = %d", n)
+	}
+
+	if err := Empty(); err != nil {
+		t.Fatalf("Empty: %v", err)
+	}
+
+	if n, _ := Count(); n != 0 {
+		t.Errorf("post-empty count = %d, want 0", n)
+	}
+	for _, sub := range []string{"files", "info"} {
+		ents, err := os.ReadDir(filepath.Join(trashDir, sub))
+		if err != nil {
+			t.Fatalf("readdir %s: %v", sub, err)
+		}
+		if len(ents) != 0 {
+			t.Errorf("%s/ has %d entries, want 0", sub, len(ents))
+		}
+	}
+}
+
+func TestRestoreToOriginalPath(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	src := filepath.Join(homeRoot, "sub", "dir", "thing.txt")
+	writeFile(t, src, "payload")
+
+	entry, err := Put(src)
+	if err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	os.RemoveAll(filepath.Join(homeRoot, "sub"))
+
+	if err := Restore(entry.Name, trashDir); err != nil {
+		t.Fatalf("Restore: %v", err)
+	}
+
+	body, err := os.ReadFile(src)
+	if err != nil {
+		t.Fatalf("read restored: %v", err)
+	}
+	if string(body) != "payload" {
+		t.Errorf("restored content = %q, want %q", body, "payload")
+	}
+
+	if _, err := os.Stat(entry.InfoPath); !os.IsNotExist(err) {
+		t.Errorf("info file still present: %v", err)
+	}
+	if _, err := os.Stat(entry.FilesPath); !os.IsNotExist(err) {
+		t.Errorf("files entry still present: %v", err)
+	}
+}
+
+func TestRestoreRefusesToOverwrite(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	src := filepath.Join(homeRoot, "keep.txt")
+	writeFile(t, src, "v1")
+
+	entry, err := Put(src)
+	if err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	writeFile(t, src, "v2-blocking")
+
+	err = Restore(entry.Name, trashDir)
+	if err == nil {
+		t.Fatalf("expected error on conflicting restore, got nil")
+	}
+	if !strings.Contains(err.Error(), "exists") {
+		t.Errorf("error %q does not mention conflict", err)
+	}
+
+	body, _ := os.ReadFile(src)
+	if string(body) != "v2-blocking" {
+		t.Errorf("blocking file altered: %q", body)
+	}
+}
+
+func TestPutDirectory(t *testing.T) {
+	homeRoot, trashDir := setupHomeTrash(t)
+
+	dir := filepath.Join(homeRoot, "myfolder")
+	writeFile(t, filepath.Join(dir, "child.txt"), "inside")
+
+	entry, err := Put(dir)
+	if err != nil {
+		t.Fatalf("Put dir: %v", err)
+	}
+	if !entry.IsDir {
+		t.Errorf("IsDir = false, want true")
+	}
+
+	moved := filepath.Join(trashDir, "files", "myfolder", "child.txt")
+	body, err := os.ReadFile(moved)
+	if err != nil {
+		t.Fatalf("read moved child: %v", err)
+	}
+	if string(body) != "inside" {
+		t.Errorf("child content = %q", body)
+	}
+}
+
+func TestIsValidSharedTrashRejectsSymlink(t *testing.T) {
+	tmp := t.TempDir()
+	target := filepath.Join(tmp, "real")
+	if err := os.MkdirAll(target, os.ModeSticky|0o777); err != nil {
+		t.Fatalf("mkdir target: %v", err)
+	}
+
+	link := filepath.Join(tmp, ".Trash")
+	if err := os.Symlink(target, link); err != nil {
+		t.Fatalf("symlink: %v", err)
+	}
+	if isValidSharedTrash(link) {
+		t.Errorf("symlinked .Trash accepted; spec requires rejection")
+	}
+}
+
+func TestIsValidSharedTrashRequiresStickyBit(t *testing.T) {
+	tmp := t.TempDir()
+	dir := filepath.Join(tmp, ".Trash")
+	if err := os.MkdirAll(dir, 0o777); err != nil {
+		t.Fatalf("mkdir: %v", err)
+	}
+	if isValidSharedTrash(dir) {
+		t.Errorf(".Trash without sticky bit accepted; spec requires rejection")
+	}
+
+	if err := os.Chmod(dir, os.ModeSticky|0o777); err != nil {
+		t.Fatalf("chmod: %v", err)
+	}
+	if !isValidSharedTrash(dir) {
+		t.Errorf(".Trash with sticky bit rejected; spec accepts it")
+	}
+}
+
+func TestPathEncodeRoundTrip(t *testing.T) {
+	cases := []string{
+		"/home/u/file.txt",
+		"/path with spaces/and-symbols & %.txt",
+		"relative/path/é unicode.md",
+	}
+	for _, in := range cases {
+		got := pathDecode(pathEncode(in))
+		if got != in {
+			t.Errorf("round-trip %q -> %q", in, got)
+		}
+	}
+}