+// caller must have read lock.
+func (dn *dirnode) marshalManifest(prefix string) (string, error) {
+ var streamLen int64
+ type m1segment struct {
+ name string
+ offset int64
+ length int64
+ }
+ var segments []m1segment
+ var subdirs string
+ var blocks []string
+
+ if err := dn.sync(); err != nil {
+ return "", err
+ }
+
+ names := make([]string, 0, len(dn.inodes))
+ for name, node := range dn.inodes {
+ names = append(names, name)
+ node.Lock()
+ defer node.Unlock()
+ }
+ sort.Strings(names)
+
+ for _, name := range names {
+ node := dn.inodes[name]
+ switch node := node.(type) {
+ case *dirnode:
+ subdir, err := node.marshalManifest(prefix + "/" + name)
+ if err != nil {
+ return "", err
+ }
+ subdirs = subdirs + subdir
+ case *filenode:
+ if len(node.extents) == 0 {
+ segments = append(segments, m1segment{name: name})
+ break
+ }
+ for _, e := range node.extents {
+ switch e := e.(type) {
+ case storedExtent:
+ if len(blocks) > 0 && blocks[len(blocks)-1] == e.locator {
+ streamLen -= int64(e.size)
+ } else {
+ blocks = append(blocks, e.locator)
+ }
+ next := m1segment{
+ name: name,
+ offset: streamLen + int64(e.offset),
+ length: int64(e.length),
+ }
+ if prev := len(segments) - 1; prev >= 0 &&
+ segments[prev].name == name &&
+ segments[prev].offset+segments[prev].length == next.offset {
+ segments[prev].length += next.length
+ } else {
+ segments = append(segments, next)
+ }
+ streamLen += int64(e.size)
+ default:
+ // This can't happen: we
+ // haven't unlocked since
+ // calling sync().
+ panic(fmt.Sprintf("can't marshal extent type %T", e))
+ }
+ }
+ default:
+ panic(fmt.Sprintf("can't marshal inode type %T", node))
+ }
+ }
+ var filetokens []string
+ for _, s := range segments {
+ filetokens = append(filetokens, fmt.Sprintf("%d:%d:%s", s.offset, s.length, manifestEscape(s.name)))
+ }
+ if len(filetokens) == 0 {
+ return subdirs, nil
+ } else if len(blocks) == 0 {
+ blocks = []string{"d41d8cd98f00b204e9800998ecf8427e+0"}
+ }
+ return manifestEscape(prefix) + " " + strings.Join(blocks, " ") + " " + strings.Join(filetokens, " ") + "\n" + subdirs, nil
+}
+
+func (dn *dirnode) loadManifest(txt string) error {
+ // FIXME: faster
+ var dirname string
+ streams := strings.Split(txt, "\n")
+ if streams[len(streams)-1] != "" {
+ return fmt.Errorf("line %d: no trailing newline", len(streams))
+ }
+ for i, stream := range streams[:len(streams)-1] {
+ lineno := i + 1
+ var extents []storedExtent
+ var anyFileTokens bool
+ var pos int64
+ var extIdx int
+ for i, token := range strings.Split(stream, " ") {
+ if i == 0 {
+ dirname = manifestUnescape(token)
+ continue
+ }
+ if !strings.Contains(token, ":") {
+ if anyFileTokens {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ toks := strings.SplitN(token, "+", 3)
+ if len(toks) < 2 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+ length, err := strconv.ParseInt(toks[1], 10, 32)
+ if err != nil || length < 0 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+ extents = append(extents, storedExtent{
+ locator: token,
+ size: int(length),
+ offset: 0,
+ length: int(length),
+ })
+ continue
+ } else if len(extents) == 0 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+
+ toks := strings.Split(token, ":")
+ if len(toks) != 3 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ anyFileTokens = true
+
+ offset, err := strconv.ParseInt(toks[0], 10, 64)
+ if err != nil || offset < 0 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ length, err := strconv.ParseInt(toks[1], 10, 64)
+ if err != nil || length < 0 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ name := path.Clean(dirname + "/" + manifestUnescape(toks[2]))
+ fnode, err := dn.createFileAndParents(name)
+ if err != nil {
+ return fmt.Errorf("line %d: cannot use path %q: %s", lineno, name, err)
+ }
+ // Map the stream offset/range coordinates to
+ // block/offset/range coordinates and add
+ // corresponding storedExtents to the filenode
+ if pos > offset {
+ // Can't continue where we left off.
+ // TODO: binary search instead of
+ // rewinding all the way (but this
+ // situation might be rare anyway)
+ extIdx, pos = 0, 0
+ }
+ for next := int64(0); extIdx < len(extents); extIdx, pos = extIdx+1, next {
+ e := extents[extIdx]
+ next = pos + int64(e.Len())
+ if next <= offset || e.Len() == 0 {
+ pos = next
+ continue
+ }
+ if pos >= offset+length {
+ break
+ }
+ var blkOff int
+ if pos < offset {
+ blkOff = int(offset - pos)
+ }
+ blkLen := e.Len() - blkOff
+ if pos+int64(blkOff+blkLen) > offset+length {
+ blkLen = int(offset + length - pos - int64(blkOff))
+ }
+ fnode.appendExtent(storedExtent{
+ kc: dn.kc,
+ locator: e.locator,
+ size: e.size,
+ offset: blkOff,
+ length: blkLen,
+ })
+ if next > offset+length {
+ break
+ }
+ }
+ if extIdx == len(extents) && pos < offset+length {
+ return fmt.Errorf("line %d: invalid segment in %d-byte stream: %q", lineno, pos, token)
+ }
+ }
+ if !anyFileTokens {
+ return fmt.Errorf("line %d: no file segments", lineno)
+ } else if len(extents) == 0 {
+ return fmt.Errorf("line %d: no locators", lineno)
+ } else if dirname == "" {
+ return fmt.Errorf("line %d: no stream name", lineno)
+ }
+ }
+ return nil
+}
+
+// only safe to call from loadManifest -- no locking
+func (dn *dirnode) createFileAndParents(path string) (fn *filenode, err error) {
+ names := strings.Split(path, "/")
+ if basename := names[len(names)-1]; basename == "" || basename == "." || basename == ".." {
+ err = fmt.Errorf("invalid filename")
+ return
+ }
+ var node inode = dn
+ for i, name := range names {
+ dn, ok := node.(*dirnode)
+ if !ok {
+ err = ErrFileExists
+ return
+ }
+ if name == "" || name == "." {