// 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 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
}