// 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
}
func (w *Walker) walkRegular(relPath string, info os.FileInfo, mtime time.Time, fchan chan protocol.FileInfo) error {
curMode := uint32(info.Mode())
if runtime.GOOS == "windows" && osutil.IsWindowsExecutable(relPath) {
curMode |= 0111
}
var currentVersion protocol.Vector
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(relPath)
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
}
currentVersion = cf.Version
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: relPath,
Version: currentVersion.Update(w.ShortID),
Flags: flags,
Modified: mtime.Unix(),
CachedSize: info.Size(),
}
l.Debugln("to hash:", relPath, f)
select {
case fchan <- f:
case <-w.Cancel:
return errors.New("cancelled")
}
return nil
}
func (w *Walker) walkDir(relPath string, info os.FileInfo, mtime time.Time, dchan chan protocol.FileInfo) error {
var currentVersion protocol.Vector
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(relPath)
permUnchanged := w.IgnorePerms || !cf.HasPermissionBits() || PermsEqual(cf.Flags, uint32(info.Mode()))
if ok && permUnchanged && !cf.IsDeleted() && cf.IsDirectory() && !cf.IsSymlink() && !cf.IsInvalid() {
return nil
}
currentVersion = cf.Version
}
flags := uint32(protocol.FlagDirectory)
if w.IgnorePerms {
flags |= protocol.FlagNoPermBits | 0777
} else {
flags |= uint32(info.Mode() & maskModePerm)
}
f := protocol.FileInfo{
Name: relPath,
Version: currentVersion.Update(w.ShortID),
Flags: flags,
Modified: mtime.Unix(),
}
l.Debugln("dir:", relPath, f)
select {
case dchan <- f:
case <-w.Cancel:
return errors.New("cancelled")
}
return nil
}
func (f *rwFolder) inConflict(current, replacement protocol.Vector) bool {
if current.Concurrent(replacement) {
// Obvious case
return true
}
if replacement.Counter(f.model.shortID) > current.Counter(f.model.shortID) {
// The replacement file contains a higher version for ourselves than
// what we have. This isn't supposed to be possible, since it's only
// we who can increment that counter. We take it as a sign that
// something is wrong (our index may have been corrupted or removed)
// and flag it as a conflict.
return true
}
return false
}