示例#1
0
文件: walk.go 项目: wmwwmv/syncthing
// walkSymlinks returns true if the symlink should be skipped, or an error if
// we should stop walking altogether. filepath.Walk isn't supposed to
// transcend into symlinks at all, but there are rumours that this may have
// happened anyway under some circumstances, possibly Windows reparse points
// or something. Hence the "skip" return from this one.
func (w *Walker) walkSymlink(absPath, relPath string, dchan chan protocol.FileInfo) (skip bool, err error) {
	// If the target is a directory, do NOT descend down there. This will
	// cause files to get tracked, and removing the symlink will as a result
	// remove files in their real location.
	if !symlinks.Supported {
		return true, nil
	}

	// We always rehash symlinks as they have no modtime or
	// permissions. We check if they point to the old target by
	// checking that their existing blocks match with the blocks in
	// the index.

	target, targetType, err := symlinks.Read(absPath)
	if err != nil {
		l.Debugln("readlink error:", absPath, err)
		return true, nil
	}

	blocks, err := Blocks(strings.NewReader(target), w.BlockSize, 0, nil)
	if err != nil {
		l.Debugln("hash link error:", absPath, err)
		return true, nil
	}

	var currentVersion protocol.Vector
	if w.CurrentFiler != nil {
		// A symlink is "unchanged", if
		//  - it exists
		//  - it wasn't deleted (because it isn't now)
		//  - it was a symlink
		//  - it wasn't invalid
		//  - the symlink type (file/dir) was the same
		//  - the block list (i.e. hash of target) was the same
		cf, ok := w.CurrentFiler.CurrentFile(relPath)
		if ok && !cf.IsDeleted() && cf.IsSymlink() && !cf.IsInvalid() && SymlinkTypeEqual(targetType, cf) && BlocksEqual(cf.Blocks, blocks) {
			return true, nil
		}
		currentVersion = cf.Version
	}

	f := protocol.FileInfo{
		Name:     relPath,
		Version:  currentVersion.Update(w.ShortID),
		Flags:    uint32(protocol.FlagSymlink | protocol.FlagNoPermBits | 0666 | SymlinkFlags(targetType)),
		Modified: 0,
		Blocks:   blocks,
	}

	l.Debugln("symlink changedb:", absPath, f)

	select {
	case dchan <- f:
	case <-w.Cancel:
		return false, errors.New("cancelled")
	}

	return false, nil
}
示例#2
0
文件: walk.go 项目: nrm21/syncthing
// walkSymlinks returns true if the symlink should be skipped, or an error if
// we should stop walking altogether. filepath.Walk isn't supposed to
// transcend into symlinks at all, but there are rumours that this may have
// happened anyway under some circumstances, possibly Windows reparse points
// or something. Hence the "skip" return from this one.
func (w *walker) walkSymlink(absPath, relPath string, dchan chan protocol.FileInfo) (skip bool, err error) {
	// If the target is a directory, do NOT descend down there. This will
	// cause files to get tracked, and removing the symlink will as a result
	// remove files in their real location.
	if !symlinks.Supported {
		return true, nil
	}

	// We always rehash symlinks as they have no modtime or
	// permissions. We check if they point to the old target by
	// checking that their existing blocks match with the blocks in
	// the index.

	target, targetType, err := symlinks.Read(absPath)
	if err != nil {
		l.Debugln("readlink error:", absPath, err)
		return true, nil
	}

	// A symlink is "unchanged", if
	//  - it exists
	//  - it wasn't deleted (because it isn't now)
	//  - it was a symlink
	//  - it wasn't invalid
	//  - the symlink type (file/dir) was the same
	//  - the target was the same
	cf, ok := w.CurrentFiler.CurrentFile(relPath)
	if ok && !cf.IsDeleted() && cf.IsSymlink() && !cf.IsInvalid() && SymlinkTypeEqual(targetType, cf) && cf.SymlinkTarget == target {
		return true, nil
	}

	f := protocol.FileInfo{
		Name:          relPath,
		Type:          SymlinkType(targetType),
		Version:       cf.Version.Update(w.ShortID),
		NoPermissions: true, // Symlinks don't have permissions of their own
		SymlinkTarget: target,
	}

	l.Debugln("symlink changedb:", absPath, f)

	select {
	case dchan <- f:
	case <-w.Cancel:
		return false, errors.New("cancelled")
	}

	return false, nil
}
示例#3
0
func (w *Walker) walkAndHashFiles(fchan, dchan chan protocol.FileInfo) filepath.WalkFunc {
	now := time.Now()
	return func(p string, info os.FileInfo, err error) error {
		// Return value used when we are returning early and don't want to
		// process the item. For directories, this means do-not-descend.
		var skip error // nil
		// info nil when error is not nil
		if info != nil && info.IsDir() {
			skip = filepath.SkipDir
		}

		if err != nil {
			if debug {
				l.Debugln("error:", p, info, err)
			}
			return skip
		}

		rn, err := filepath.Rel(w.Dir, p)
		if err != nil {
			if debug {
				l.Debugln("rel error:", p, err)
			}
			return skip
		}

		if rn == "." {
			return nil
		}

		mtime := info.ModTime()
		if w.MtimeRepo != nil {
			mtime = w.MtimeRepo.GetMtime(rn, mtime)
		}

		if w.TempNamer != nil && w.TempNamer.IsTemporary(rn) {
			// A temporary file
			if debug {
				l.Debugln("temporary:", rn)
			}
			if info.Mode().IsRegular() && mtime.Add(w.TempLifetime).Before(now) {
				os.Remove(p)
				if debug {
					l.Debugln("removing temporary:", rn, mtime)
				}
			}
			return nil
		}

		if sn := filepath.Base(rn); sn == ".stignore" || sn == ".stfolder" ||
			strings.HasPrefix(rn, ".stversions") || (w.Matcher != nil && w.Matcher.Match(rn)) {
			// An ignored file
			if debug {
				l.Debugln("ignored:", rn)
			}
			return skip
		}

		if !utf8.ValidString(rn) {
			l.Warnf("File name %q is not in UTF8 encoding; skipping.", rn)
			return skip
		}

		var normalizedRn string
		if runtime.GOOS == "darwin" {
			// Mac OS X file names should always be NFD normalized.
			normalizedRn = norm.NFD.String(rn)
		} else {
			// Every other OS in the known universe uses NFC or just plain
			// doesn't bother to define an encoding. In our case *we* do care,
			// so we enforce NFC regardless.
			normalizedRn = norm.NFC.String(rn)
		}

		if rn != normalizedRn {
			// The file name was not normalized.

			if !w.AutoNormalize {
				// We're not authorized to do anything about it, so complain and skip.

				l.Warnf("File name %q is not in the correct UTF8 normalization form; skipping.", rn)
				return skip
			}

			// We will attempt to normalize it.
			normalizedPath := filepath.Join(w.Dir, normalizedRn)
			if _, err := osutil.Lstat(normalizedPath); os.IsNotExist(err) {
				// Nothing exists with the normalized filename. Good.
				if err = os.Rename(p, normalizedPath); err != nil {
					l.Infof(`Error normalizing UTF8 encoding of file "%s": %v`, rn, err)
					return skip
				}
				l.Infof(`Normalized UTF8 encoding of file name "%s".`, rn)
			} else {
				// There is something already in the way at the normalized
				// file name.
				l.Infof(`File "%s" has UTF8 encoding conflict with another file; ignoring.`, rn)
				return skip
			}

			rn = normalizedRn
		}

		var cf protocol.FileInfo
		var ok bool

		// Index wise symlinks are always files, regardless of what the target
		// is, because symlinks carry their target path as their content.
		if info.Mode()&os.ModeSymlink == os.ModeSymlink {
			// If the target is a directory, do NOT descend down there. This
			// will cause files to get tracked, and removing the symlink will
			// as a result remove files in their real location.
			if !symlinks.Supported {
				return skip
			}

			// We always rehash symlinks as they have no modtime or
			// permissions. We check if they point to the old target by
			// checking that their existing blocks match with the blocks in
			// the index.

			target, targetType, err := symlinks.Read(p)
			if err != nil {
				if debug {
					l.Debugln("readlink error:", p, err)
				}
				return skip
			}

			blocks, err := Blocks(strings.NewReader(target), w.BlockSize, 0, nil)
			if err != nil {
				if debug {
					l.Debugln("hash link error:", p, err)
				}
				return skip
			}

			if w.CurrentFiler != nil {
				// A symlink is "unchanged", if
				//  - it exists
				//  - it wasn't deleted (because it isn't now)
				//  - it was a symlink
				//  - it wasn't invalid
				//  - the symlink type (file/dir) was the same
				//  - the block list (i.e. hash of target) was the same
				cf, ok = w.CurrentFiler.CurrentFile(rn)
				if ok && !cf.IsDeleted() && cf.IsSymlink() && !cf.IsInvalid() && SymlinkTypeEqual(targetType, cf) && BlocksEqual(cf.Blocks, blocks) {
					return skip
				}
			}

			f := protocol.FileInfo{
				Name:     rn,
				Version:  cf.Version.Update(w.ShortID),
				Flags:    uint32(protocol.FlagSymlink | protocol.FlagNoPermBits | 0666 | SymlinkFlags(targetType)),
				Modified: 0,
				Blocks:   blocks,
			}

			if debug {
				l.Debugln("symlink changedb:", p, f)
			}

			dchan <- f

			return skip
		}

		if info.Mode().IsDir() {
			if w.CurrentFiler != nil {
				// A directory is "unchanged", if it
				//  - exists
				//  - has the same permissions as previously, unless we are ignoring permissions
				//  - was not marked deleted (since it apparently exists now)
				//  - was a directory previously (not a file or something else)
				//  - was not a symlink (since it's a directory now)
				//  - was not invalid (since it looks valid now)
				cf, ok = w.CurrentFiler.CurrentFile(rn)
				permUnchanged := w.IgnorePerms || !cf.HasPermissionBits() || PermsEqual(cf.Flags, uint32(info.Mode()))
				if ok && permUnchanged && !cf.IsDeleted() && cf.IsDirectory() && !cf.IsSymlink() && !cf.IsInvalid() {
					return nil
				}
			}

			flags := uint32(protocol.FlagDirectory)
			if w.IgnorePerms {
				flags |= protocol.FlagNoPermBits | 0777
			} else {
				flags |= uint32(info.Mode() & maskModePerm)
			}
			f := protocol.FileInfo{
				Name:     rn,
				Version:  cf.Version.Update(w.ShortID),
				Flags:    flags,
				Modified: mtime.Unix(),
			}
			if debug {
				l.Debugln("dir:", p, f)
			}
			dchan <- f
			return nil
		}

		if info.Mode().IsRegular() {
			curMode := uint32(info.Mode())
			if runtime.GOOS == "windows" && osutil.IsWindowsExecutable(rn) {
				curMode |= 0111
			}

			if w.CurrentFiler != nil {
				// A file is "unchanged", if it
				//  - exists
				//  - has the same permissions as previously, unless we are ignoring permissions
				//  - was not marked deleted (since it apparently exists now)
				//  - had the same modification time as it has now
				//  - was not a directory previously (since it's a file now)
				//  - was not a symlink (since it's a file now)
				//  - was not invalid (since it looks valid now)
				//  - has the same size as previously
				cf, ok = w.CurrentFiler.CurrentFile(rn)
				permUnchanged := w.IgnorePerms || !cf.HasPermissionBits() || PermsEqual(cf.Flags, curMode)
				if ok && permUnchanged && !cf.IsDeleted() && cf.Modified == mtime.Unix() && !cf.IsDirectory() &&
					!cf.IsSymlink() && !cf.IsInvalid() && cf.Size() == info.Size() {
					return nil
				}

				if debug {
					l.Debugln("rescan:", cf, mtime.Unix(), info.Mode()&os.ModePerm)
				}
			}

			var flags = curMode & uint32(maskModePerm)
			if w.IgnorePerms {
				flags = protocol.FlagNoPermBits | 0666
			}

			f := protocol.FileInfo{
				Name:       rn,
				Version:    cf.Version.Update(w.ShortID),
				Flags:      flags,
				Modified:   mtime.Unix(),
				CachedSize: info.Size(),
			}
			if debug {
				l.Debugln("to hash:", p, f)
			}
			fchan <- f
		}

		return nil
	}
}
示例#4
0
文件: util.go 项目: wmwwmv/syncthing
func startWalker(dir string, res chan<- fileInfo, abort <-chan struct{}) chan error {
	walker := func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}

		rn, _ := filepath.Rel(dir, path)
		if rn == "." || rn == ".stfolder" {
			return nil
		}
		if rn == ".stversions" {
			return filepath.SkipDir
		}

		var f fileInfo
		if info.Mode()&os.ModeSymlink != 0 {
			f = fileInfo{
				name: rn,
				mode: os.ModeSymlink,
			}

			tgt, _, err := symlinks.Read(path)
			if err != nil {
				return err
			}
			h := md5.New()
			h.Write([]byte(tgt))
			hash := h.Sum(nil)

			copy(f.hash[:], hash)
		} else if info.IsDir() {
			f = fileInfo{
				name: rn,
				mode: info.Mode(),
				// hash and modtime zero for directories
			}
		} else {
			f = fileInfo{
				name: rn,
				mode: info.Mode(),
				mod:  info.ModTime().Unix(),
				size: info.Size(),
			}
			sum, err := md5file(path)
			if err != nil {
				return err
			}
			f.hash = sum
		}

		select {
		case res <- f:
			return nil
		case <-abort:
			return errors.New("abort")
		}
	}

	errc := make(chan error)
	go func() {
		err := filepath.Walk(dir, walker)
		close(res)
		if err != nil {
			errc <- err
		}
		close(errc)
	}()
	return errc
}