1
mirror of https://github.com/rclone/rclone synced 2024-12-13 01:13:58 +01:00
rclone/local/local.go
Zhiming Wang 6152bab28d local: add --skip-links to suppress symlink warnings
Give users a way to explicitly acknowledge that symlinks are to be skipped
without warnings.

Fixes #1480.
2017-07-23 15:02:02 +01:00

902 lines
22 KiB
Go

// Package local provides a filesystem interface
package local
import (
"fmt"
"io"
"io/ioutil"
"os"
"path"
"path/filepath"
"regexp"
"runtime"
"strings"
"sync"
"time"
"unicode/utf8"
"golang.org/x/text/unicode/norm"
"github.com/ncw/rclone/fs"
"github.com/pkg/errors"
)
var (
followSymlinks = fs.BoolP("copy-links", "L", false, "Follow symlinks and copy the pointed to item.")
skipSymlinks = fs.BoolP("skip-links", "", false, "Don't warn about skipped symlinks.")
noUTFNorm = fs.BoolP("local-no-unicode-normalization", "", false, "Don't apply unicode normalization to paths and filenames")
)
// Constants
const devUnset = 0xdeadbeefcafebabe // a device id meaning it is unset
// Register with Fs
func init() {
fsi := &fs.RegInfo{
Name: "local",
Description: "Local Disk",
NewFs: NewFs,
Options: []fs.Option{{
Name: "nounc",
Help: "Disable UNC (long path names) conversion on Windows",
Optional: true,
Examples: []fs.OptionExample{{
Value: "true",
Help: "Disables long file names",
}},
}},
}
fs.Register(fsi)
}
// Fs represents a local filesystem rooted at root
type Fs struct {
name string // the name of the remote
root string // The root directory (OS path)
features *fs.Features // optional features
dev uint64 // device number of root node
precisionOk sync.Once // Whether we need to read the precision
precision time.Duration // precision of local filesystem
wmu sync.Mutex // used for locking access to 'warned'.
warned map[string]struct{} // whether we have warned about this string
nounc bool // Skip UNC conversion on Windows
// do os.Lstat or os.Stat
lstat func(name string) (os.FileInfo, error)
dirNames *mapper // directory name mapping
}
// Object represents a local filesystem object
type Object struct {
fs *Fs // The Fs this object is part of
remote string // The remote path - properly UTF-8 encoded - for rclone
path string // The local path - may not be properly UTF-8 encoded - for OS
size int64 // file metadata - always present
mode os.FileMode
modTime time.Time
hashes map[fs.HashType]string // Hashes
}
// ------------------------------------------------------------
// NewFs constructs an Fs from the path
func NewFs(name, root string) (fs.Fs, error) {
var err error
nounc := fs.ConfigFileGet(name, "nounc")
f := &Fs{
name: name,
warned: make(map[string]struct{}),
nounc: nounc == "true",
dev: devUnset,
lstat: os.Lstat,
dirNames: newMapper(),
}
f.root = f.cleanPath(root)
f.features = (&fs.Features{CaseInsensitive: f.caseInsensitive()}).Fill(f)
if *followSymlinks {
f.lstat = os.Stat
}
// Check to see if this points to a file
fi, err := f.lstat(f.root)
if err == nil {
f.dev = readDevice(fi)
}
if err == nil && fi.Mode().IsRegular() {
// It is a file, so use the parent as the root
f.root, _ = getDirFile(f.root)
// return an error with an fs which points to the parent
return f, fs.ErrorIsFile
}
return f, nil
}
// Name of the remote (as passed into NewFs)
func (f *Fs) Name() string {
return f.name
}
// Root of the remote (as passed into NewFs)
func (f *Fs) Root() string {
return f.root
}
// String converts this Fs to a string
func (f *Fs) String() string {
return fmt.Sprintf("Local file system at %s", f.root)
}
// Features returns the optional features of this Fs
func (f *Fs) Features() *fs.Features {
return f.features
}
// caseInsenstive returns whether the remote is case insensitive or not
func (f *Fs) caseInsensitive() bool {
// FIXME not entirely accurate since you can have case
// sensitive Fses on darwin and case insenstive Fses on linux.
// Should probably check but that would involve creating a
// file in the remote to be most accurate which probably isn't
// desirable.
return runtime.GOOS == "windows" || runtime.GOOS == "darwin"
}
// newObject makes a half completed Object
//
// if dstPath is empty then it is made from remote
func (f *Fs) newObject(remote, dstPath string) *Object {
if dstPath == "" {
dstPath = f.cleanPath(filepath.Join(f.root, remote))
}
remote = f.cleanRemote(remote)
return &Object{
fs: f,
remote: remote,
path: dstPath,
}
}
// Return an Object from a path
//
// May return nil if an error occurred
func (f *Fs) newObjectWithInfo(remote, dstPath string, info os.FileInfo) (fs.Object, error) {
o := f.newObject(remote, dstPath)
if info != nil {
o.setMetadata(info)
} else {
err := o.lstat()
if err != nil {
if os.IsNotExist(err) {
return nil, fs.ErrorObjectNotFound
}
return nil, err
}
}
if o.mode.IsDir() {
return nil, errors.Wrapf(fs.ErrorNotAFile, "%q", remote)
}
return o, nil
}
// NewObject finds the Object at remote. If it can't be found
// it returns the error ErrorObjectNotFound.
func (f *Fs) NewObject(remote string) (fs.Object, error) {
return f.newObjectWithInfo(remote, "", nil)
}
// List the objects and directories in dir into entries. The
// entries can be returned in any order but should be for a
// complete directory.
//
// dir should be "" to list the root, and should not have
// trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
func (f *Fs) List(dir string) (entries fs.DirEntries, err error) {
dir = f.dirNames.Load(dir)
fsDirPath := f.cleanPath(filepath.Join(f.root, dir))
remote := f.cleanRemote(dir)
_, err = os.Stat(fsDirPath)
if err != nil {
return nil, fs.ErrorDirNotFound
}
fd, err := os.Open(fsDirPath)
if err != nil {
return nil, errors.Wrapf(err, "failed to open directory %q", dir)
}
defer func() {
cerr := fd.Close()
if cerr != nil && err == nil {
err = errors.Wrapf(cerr, "failed to close directory %q:", dir)
}
}()
for {
fis, err := fd.Readdir(1024)
if err == io.EOF && len(fis) == 0 {
break
}
if err != nil {
return nil, errors.Wrapf(err, "failed to read directory %q", dir)
}
for _, fi := range fis {
name := fi.Name()
mode := fi.Mode()
newRemote := path.Join(remote, name)
newPath := filepath.Join(fsDirPath, name)
// Follow symlinks if required
if *followSymlinks && (mode&os.ModeSymlink) != 0 {
fi, err = os.Stat(newPath)
if err != nil {
return nil, err
}
mode = fi.Mode()
}
if fi.IsDir() {
// Ignore directories which are symlinks. These are junction points under windows which
// are kind of a souped up symlink. Unix doesn't have directories which are symlinks.
if (mode&os.ModeSymlink) == 0 && f.dev == readDevice(fi) {
d := fs.NewDir(f.dirNames.Save(newRemote, f.cleanRemote(newRemote)), fi.ModTime())
entries = append(entries, d)
}
} else {
fso, err := f.newObjectWithInfo(newRemote, newPath, fi)
if err != nil {
return nil, err
}
if fso.Storable() {
entries = append(entries, fso)
}
}
}
}
return entries, nil
}
// cleanRemote makes string a valid UTF-8 string for remote strings.
//
// Any invalid UTF-8 characters will be replaced with utf8.RuneError
// It also normalises the UTF-8 and converts the slashes if necessary.
func (f *Fs) cleanRemote(name string) string {
if !utf8.ValidString(name) {
f.wmu.Lock()
if _, ok := f.warned[name]; !ok {
fs.Logf(f, "Replacing invalid UTF-8 characters in %q", name)
f.warned[name] = struct{}{}
}
f.wmu.Unlock()
name = string([]rune(name))
}
if !*noUTFNorm {
name = norm.NFC.String(name)
}
name = filepath.ToSlash(name)
return name
}
// mapper maps raw to cleaned directory names
type mapper struct {
mu sync.RWMutex // mutex to protect the below
m map[string]string // map of un-normalised directory names
}
func newMapper() *mapper {
return &mapper{
m: make(map[string]string),
}
}
// Lookup a directory name to make a local name (reverses
// cleanDirName)
//
// FIXME this is temporary before we make a proper Directory object
func (m *mapper) Load(in string) string {
m.mu.RLock()
out, ok := m.m[in]
m.mu.RUnlock()
if ok {
return out
}
return in
}
// Cleans a directory name recording if it needed to be altered
//
// FIXME this is temporary before we make a proper Directory object
func (m *mapper) Save(in, out string) string {
if in != out {
m.mu.Lock()
m.m[out] = in
m.mu.Unlock()
}
return out
}
// Put the Object to the local filesystem
func (f *Fs) Put(in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
remote := src.Remote()
// Temporary Object under construction - info filled in by Update()
o := f.newObject(remote, "")
err := o.Update(in, src, options...)
if err != nil {
return nil, err
}
return o, nil
}
// Mkdir creates the directory if it doesn't exist
func (f *Fs) Mkdir(dir string) error {
// FIXME: https://github.com/syncthing/syncthing/blob/master/lib/osutil/mkdirall_windows.go
root := f.cleanPath(filepath.Join(f.root, dir))
err := os.MkdirAll(root, 0777)
if err != nil {
return err
}
if dir == "" {
fi, err := f.lstat(root)
if err != nil {
return err
}
f.dev = readDevice(fi)
}
return nil
}
// Rmdir removes the directory
//
// If it isn't empty it will return an error
func (f *Fs) Rmdir(dir string) error {
root := f.cleanPath(filepath.Join(f.root, dir))
return os.Remove(root)
}
// Precision of the file system
func (f *Fs) Precision() (precision time.Duration) {
f.precisionOk.Do(func() {
f.precision = f.readPrecision()
})
return f.precision
}
// Read the precision
func (f *Fs) readPrecision() (precision time.Duration) {
// Default precision of 1s
precision = time.Second
// Create temporary file and test it
fd, err := ioutil.TempFile("", "rclone")
if err != nil {
// If failed return 1s
// fmt.Println("Failed to create temp file", err)
return time.Second
}
path := fd.Name()
// fmt.Println("Created temp file", path)
err = fd.Close()
if err != nil {
return time.Second
}
// Delete it on return
defer func() {
// fmt.Println("Remove temp file")
_ = os.Remove(path) // ignore error
}()
// Find the minimum duration we can detect
for duration := time.Duration(1); duration < time.Second; duration *= 10 {
// Current time with delta
t := time.Unix(time.Now().Unix(), int64(duration))
err := os.Chtimes(path, t, t)
if err != nil {
// fmt.Println("Failed to Chtimes", err)
break
}
// Read the actual time back
fi, err := os.Stat(path)
if err != nil {
// fmt.Println("Failed to Stat", err)
break
}
// If it matches - have found the precision
// fmt.Println("compare", fi.ModTime(), t)
if fi.ModTime() == t {
// fmt.Println("Precision detected as", duration)
return duration
}
}
return
}
// Purge deletes all the files and directories
//
// Optional interface: Only implement this if you have a way of
// deleting all the files quicker than just running Remove() on the
// result of List()
func (f *Fs) Purge() error {
fi, err := f.lstat(f.root)
if err != nil {
return err
}
if !fi.Mode().IsDir() {
return errors.Errorf("can't purge non directory: %q", f.root)
}
return os.RemoveAll(f.root)
}
// Move src to this remote using server side move operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantMove
func (f *Fs) Move(src fs.Object, remote string) (fs.Object, error) {
srcObj, ok := src.(*Object)
if !ok {
fs.Debugf(src, "Can't move - not same remote type")
return nil, fs.ErrorCantMove
}
// Temporary Object under construction
dstObj := f.newObject(remote, "")
// Check it is a file if it exists
err := dstObj.lstat()
if os.IsNotExist(err) {
// OK
} else if err != nil {
return nil, err
} else if !dstObj.mode.IsRegular() {
// It isn't a file
return nil, errors.New("can't move file onto non-file")
}
// Create destination
err = dstObj.mkdirAll()
if err != nil {
return nil, err
}
// Do the move
err = os.Rename(srcObj.path, dstObj.path)
if err != nil {
return nil, err
}
// Update the info
err = dstObj.lstat()
if err != nil {
return nil, err
}
return dstObj, nil
}
// DirMove moves src, srcRemote to this remote at dstRemote
// using server side move operations.
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantDirMove
//
// If destination exists then return fs.ErrorDirExists
func (f *Fs) DirMove(src fs.Fs, srcRemote, dstRemote string) error {
srcFs, ok := src.(*Fs)
if !ok {
fs.Debugf(srcFs, "Can't move directory - not same remote type")
return fs.ErrorCantDirMove
}
srcPath := f.cleanPath(filepath.Join(srcFs.root, srcRemote))
dstPath := f.cleanPath(filepath.Join(f.root, dstRemote))
// Check if destination exists
_, err := os.Lstat(dstPath)
if !os.IsNotExist(err) {
return fs.ErrorDirExists
}
// Create parent of destination
dstParentPath, _ := getDirFile(dstPath)
err = os.MkdirAll(dstParentPath, 0777)
if err != nil {
return err
}
// Do the move
return os.Rename(srcPath, dstPath)
}
// Hashes returns the supported hash sets.
func (f *Fs) Hashes() fs.HashSet {
return fs.SupportedHashes
}
// ------------------------------------------------------------
// Fs returns the parent Fs
func (o *Object) Fs() fs.Info {
return o.fs
}
// Return a string version
func (o *Object) String() string {
if o == nil {
return "<nil>"
}
return o.remote
}
// Remote returns the remote path
func (o *Object) Remote() string {
return o.remote
}
// Hash returns the requested hash of a file as a lowercase hex string
func (o *Object) Hash(r fs.HashType) (string, error) {
// Check that the underlying file hasn't changed
oldtime := o.modTime
oldsize := o.size
err := o.lstat()
if err != nil {
return "", errors.Wrap(err, "hash: failed to stat")
}
if !o.modTime.Equal(oldtime) || oldsize != o.size {
o.hashes = nil
}
if o.hashes == nil {
o.hashes = make(map[fs.HashType]string)
in, err := os.Open(o.path)
if err != nil {
return "", errors.Wrap(err, "hash: failed to open")
}
o.hashes, err = fs.HashStream(in)
closeErr := in.Close()
if err != nil {
return "", errors.Wrap(err, "hash: failed to read")
}
if closeErr != nil {
return "", errors.Wrap(closeErr, "hash: failed to close")
}
}
return o.hashes[r], nil
}
// Size returns the size of an object in bytes
func (o *Object) Size() int64 {
return o.size
}
// ModTime returns the modification time of the object
func (o *Object) ModTime() time.Time {
return o.modTime
}
// SetModTime sets the modification time of the local fs object
func (o *Object) SetModTime(modTime time.Time) error {
err := os.Chtimes(o.path, modTime, modTime)
if err != nil {
return err
}
// Re-read metadata
return o.lstat()
}
// Storable returns a boolean showing if this object is storable
func (o *Object) Storable() bool {
// Check for control characters in the remote name and show non storable
for _, c := range o.Remote() {
if c >= 0x00 && c < 0x20 || c == 0x7F {
fs.Logf(o.fs, "Can't store file with control characters: %q", o.Remote())
return false
}
}
mode := o.mode
// On windows a file with os.ModeSymlink represents a file with reparse points
if runtime.GOOS == "windows" && (mode&os.ModeSymlink) != 0 {
fs.Debugf(o, "Clearing symlink bit to allow a file with reparse points to be copied")
mode &^= os.ModeSymlink
}
if mode&os.ModeSymlink != 0 {
if !*skipSymlinks {
fs.Logf(o, "Can't follow symlink without -L/--copy-links")
}
return false
} else if mode&(os.ModeNamedPipe|os.ModeSocket|os.ModeDevice) != 0 {
fs.Logf(o, "Can't transfer non file/directory")
return false
} else if mode&os.ModeDir != 0 {
// fs.Debugf(o, "Skipping directory")
return false
}
return true
}
// localOpenFile wraps an io.ReadCloser and updates the md5sum of the
// object that is read
type localOpenFile struct {
o *Object // object that is open
in io.ReadCloser // handle we are wrapping
hash *fs.MultiHasher // currently accumulating hashes
}
// Read bytes from the object - see io.Reader
func (file *localOpenFile) Read(p []byte) (n int, err error) {
n, err = file.in.Read(p)
if n > 0 {
// Hash routines never return an error
_, _ = file.hash.Write(p[:n])
}
return
}
// Close the object and update the hashes
func (file *localOpenFile) Close() (err error) {
err = file.in.Close()
if err == nil {
if file.hash.Size() == file.o.Size() {
file.o.hashes = file.hash.Sums()
}
}
return err
}
// Open an object for read
func (o *Object) Open(options ...fs.OpenOption) (in io.ReadCloser, err error) {
var offset int64
hashes := fs.SupportedHashes
for _, option := range options {
switch x := option.(type) {
case *fs.SeekOption:
offset = x.Offset
case *fs.HashesOption:
hashes = x.Hashes
default:
if option.Mandatory() {
fs.Logf(o, "Unsupported mandatory option: %v", option)
}
}
}
fd, err := os.Open(o.path)
if err != nil {
return
}
if offset != 0 {
// seek the object
_, err = fd.Seek(offset, 0)
// don't attempt to make checksums
return fd, err
}
hash, err := fs.NewMultiHasherTypes(hashes)
if err != nil {
return nil, err
}
// Update the md5sum as we go along
in = &localOpenFile{
o: o,
in: fd,
hash: hash,
}
return in, nil
}
// mkdirAll makes all the directories needed to store the object
func (o *Object) mkdirAll() error {
dir, _ := getDirFile(o.path)
return os.MkdirAll(dir, 0777)
}
// Update the object from in with modTime and size
func (o *Object) Update(in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) error {
hashes := fs.SupportedHashes
for _, option := range options {
switch x := option.(type) {
case *fs.HashesOption:
hashes = x.Hashes
}
}
err := o.mkdirAll()
if err != nil {
return err
}
out, err := os.OpenFile(o.path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0666)
if err != nil {
return err
}
// Calculate the hash of the object we are reading as we go along
hash, err := fs.NewMultiHasherTypes(hashes)
if err != nil {
return err
}
in = io.TeeReader(in, hash)
_, err = io.Copy(out, in)
closeErr := out.Close()
if err == nil {
err = closeErr
}
if err != nil {
fs.Logf(o, "Removing partially written file on error: %v", err)
if removeErr := os.Remove(o.path); removeErr != nil {
fs.Errorf(o, "Failed to remove partially written file: %v", removeErr)
}
return err
}
// All successful so update the hashes
o.hashes = hash.Sums()
// Set the mtime
err = o.SetModTime(src.ModTime())
if err != nil {
return err
}
// ReRead info now that we have finished
return o.lstat()
}
// setMetadata sets the file info from the os.FileInfo passed in
func (o *Object) setMetadata(info os.FileInfo) {
o.size = info.Size()
o.modTime = info.ModTime()
o.mode = info.Mode()
}
// Stat a Object into info
func (o *Object) lstat() error {
info, err := o.fs.lstat(o.path)
if err == nil {
o.setMetadata(info)
}
return err
}
// Remove an object
func (o *Object) Remove() error {
return os.Remove(o.path)
}
// Return the directory and file from an OS path. Assumes
// os.PathSeparator is used.
func getDirFile(s string) (string, string) {
i := strings.LastIndex(s, string(os.PathSeparator))
dir, file := s[:i], s[i+1:]
if dir == "" {
dir = string(os.PathSeparator)
}
return dir, file
}
// cleanPathFragment cleans an OS path fragment which is part of a
// bigger path and not necessarily absolute
func cleanPathFragment(s string) string {
if s == "" {
return s
}
s = filepath.Clean(s)
if runtime.GOOS == "windows" {
s = strings.Replace(s, `/`, `\`, -1)
}
return s
}
// cleanPath cleans and makes absolute the path passed in and returns
// an OS path.
//
// The input might be in OS form or rclone form or a mixture, but the
// output is in OS form.
//
// On windows it makes the path UNC also and replaces any characters
// Windows can't deal with with their replacements.
func (f *Fs) cleanPath(s string) string {
s = cleanPathFragment(s)
if runtime.GOOS == "windows" {
if !filepath.IsAbs(s) && !strings.HasPrefix(s, "\\") {
s2, err := filepath.Abs(s)
if err == nil {
s = s2
}
}
if !f.nounc {
// Convert to UNC
s = uncPath(s)
}
s = cleanWindowsName(f, s)
} else {
if !filepath.IsAbs(s) {
s2, err := filepath.Abs(s)
if err == nil {
s = s2
}
}
}
return s
}
// Pattern to match a windows absolute path: "c:\" and similar
var isAbsWinDrive = regexp.MustCompile(`^[a-zA-Z]\:\\`)
// uncPath converts an absolute Windows path
// to a UNC long path.
func uncPath(s string) string {
// UNC can NOT use "/", so convert all to "\"
s = strings.Replace(s, `/`, `\`, -1)
// If prefix is "\\", we already have a UNC path or server.
if strings.HasPrefix(s, `\\`) {
// If already long path, just keep it
if strings.HasPrefix(s, `\\?\`) {
return s
}
// Trim "\\" from path and add UNC prefix.
return `\\?\UNC\` + strings.TrimPrefix(s, `\\`)
}
if isAbsWinDrive.MatchString(s) {
return `\\?\` + s
}
return s
}
// cleanWindowsName will clean invalid Windows characters replacing them with _
func cleanWindowsName(f *Fs, name string) string {
original := name
var name2 string
if strings.HasPrefix(name, `\\?\`) {
name2 = `\\?\`
name = strings.TrimPrefix(name, `\\?\`)
}
if strings.HasPrefix(name, `//?/`) {
name2 = `//?/`
name = strings.TrimPrefix(name, `//?/`)
}
// Colon is allowed as part of a drive name X:\
colonAt := strings.Index(name, ":")
if colonAt > 0 && colonAt < 3 && len(name) > colonAt+1 {
// Copy to name2, which is unfiltered
name2 += name[0 : colonAt+1]
name = name[colonAt+1:]
}
name2 += strings.Map(func(r rune) rune {
switch r {
case '<', '>', '"', '|', '?', '*', ':':
return '_'
}
return r
}, name)
if name2 != original && f != nil {
f.wmu.Lock()
if _, ok := f.warned[name]; !ok {
fs.Logf(f, "Replacing invalid characters in %q to %q", name, name2)
f.warned[name] = struct{}{}
}
f.wmu.Unlock()
}
return name2
}
// Check the interfaces are satisfied
var (
_ fs.Fs = &Fs{}
_ fs.Purger = &Fs{}
_ fs.Mover = &Fs{}
_ fs.DirMover = &Fs{}
_ fs.Object = &Object{}
)