func walk(basedir, dir string, done chan struct{}, jobs chan<- Job, res chan<- Result) error {
info, err := os.Lstat(dir)
if err != nil {
debug.Log("pipe.walk", "error for %v: %v", dir, err)
return err
}
relpath, _ := filepath.Rel(basedir, dir)
if !info.IsDir() {
select {
case jobs <- Entry{info: info, basedir: basedir, path: relpath, result: res}:
case <-done:
return errCancelled
}
return nil
}
names, err := readDirNames(dir)
if err != nil {
return err
}
// Insert breakpoint to allow testing behaviour with vanishing files
// between Readdir() and lstat()
debug.RunHook("pipe.walk1", relpath)
entries := make([]<-chan Result, 0, len(names))
for _, name := range names {
subpath := filepath.Join(dir, name)
ch := make(chan Result, 1)
entries = append(entries, ch)
fi, err := os.Lstat(subpath)
if err != nil {
select {
case jobs <- Entry{info: fi, error: err, basedir: basedir, path: filepath.Join(relpath, name), result: ch}:
case <-done:
return errCancelled
}
continue
}
// Insert breakpoint to allow testing behaviour with vanishing files
// between walk and open
debug.RunHook("pipe.walk2", filepath.Join(relpath, name))
if isDir(fi) {
err = walk(basedir, subpath, done, jobs, ch)
if err != nil {
return err
}
} else {
select {
case jobs <- Entry{info: fi, basedir: basedir, path: filepath.Join(relpath, name), result: ch}:
case <-done:
return errCancelled
}
}
}
select {
case jobs <- Dir{basedir: basedir, path: relpath, info: info, Entries: entries, result: res}:
case <-done:
return errCancelled
}
return nil
}
// Snapshot creates a snapshot of the given paths. If parentID is set, this is
// used to compare the files to the ones archived at the time this snapshot was
// taken.
func (arch *Archiver) Snapshot(p *Progress, paths []string, parentID backend.ID) (*Snapshot, backend.ID, error) {
debug.Log("Archiver.Snapshot", "start for %v", paths)
debug.RunHook("Archiver.Snapshot", nil)
sort.Strings(paths)
// signal the whole pipeline to stop
done := make(chan struct{})
var err error
p.Start()
defer p.Done()
// create new snapshot
sn, err := NewSnapshot(paths)
if err != nil {
return nil, nil, err
}
sn.Excludes = arch.Excludes
jobs := archivePipe{}
// use parent snapshot (if some was given)
if parentID != nil {
sn.Parent = parentID
// load parent snapshot
parent, err := LoadSnapshot(arch.repo, parentID)
if err != nil {
return nil, nil, err
}
// start walker on old tree
ch := make(chan WalkTreeJob)
go WalkTree(arch.repo, parent.Tree, done, ch)
jobs.Old = ch
} else {
// use closed channel
ch := make(chan WalkTreeJob)
close(ch)
jobs.Old = ch
}
// start walker
pipeCh := make(chan pipe.Job)
resCh := make(chan pipe.Result, 1)
go func() {
err := pipe.Walk(paths, arch.SelectFilter, done, pipeCh, resCh)
if err != nil {
debug.Log("Archiver.Snapshot", "pipe.Walk returned error %v", err)
return
}
debug.Log("Archiver.Snapshot", "pipe.Walk done")
}()
jobs.New = pipeCh
ch := make(chan pipe.Job)
go jobs.compare(done, ch)
var wg sync.WaitGroup
entCh := make(chan pipe.Entry)
dirCh := make(chan pipe.Dir)
// split
wg.Add(1)
go func() {
pipe.Split(ch, dirCh, entCh)
debug.Log("Archiver.Snapshot", "split done")
close(dirCh)
close(entCh)
wg.Done()
}()
// run workers
for i := 0; i < maxConcurrency; i++ {
wg.Add(2)
go arch.fileWorker(&wg, p, done, entCh)
go arch.dirWorker(&wg, p, done, dirCh)
}
// wait for all workers to terminate
debug.Log("Archiver.Snapshot", "wait for workers")
wg.Wait()
debug.Log("Archiver.Snapshot", "workers terminated")
// receive the top-level tree
root := (<-resCh).(*Node)
debug.Log("Archiver.Snapshot", "root node received: %v", root.Subtree.Str())
sn.Tree = root.Subtree
// save snapshot
id, err := arch.repo.SaveJSONUnpacked(backend.Snapshot, sn)
if err != nil {
return nil, nil, err
}
// store ID in snapshot struct
sn.id = id
debug.Log("Archiver.Snapshot", "saved snapshot %v", id.Str())
// flush repository
err = arch.repo.Flush()
if err != nil {
return nil, nil, err
}
// save index
indexID, err := arch.repo.SaveIndex()
if err != nil {
debug.Log("Archiver.Snapshot", "error saving index: %v", err)
return nil, nil, err
}
debug.Log("Archiver.Snapshot", "saved index %v", indexID.Str())
return sn, id, nil
}
func walk(basedir, dir string, selectFunc SelectFunc, done <-chan struct{}, jobs chan<- Job, res chan<- Result) (excluded bool) {
debug.Log("pipe.walk", "start on %q, basedir %q", dir, basedir)
relpath, err := filepath.Rel(basedir, dir)
if err != nil {
panic(err)
}
info, err := os.Lstat(dir)
if err != nil {
debug.Log("pipe.walk", "error for %v: %v, res %p", dir, err, res)
select {
case jobs <- Dir{basedir: basedir, path: relpath, info: info, error: err, result: res}:
case <-done:
}
return
}
if !selectFunc(dir, info) {
debug.Log("pipe.walk", "file %v excluded by filter, res %p", dir, res)
excluded = true
return
}
if !info.IsDir() {
debug.Log("pipe.walk", "sending file job for %v, res %p", dir, res)
select {
case jobs <- Entry{info: info, basedir: basedir, path: relpath, result: res}:
case <-done:
}
return
}
debug.RunHook("pipe.readdirnames", dir)
names, err := readDirNames(dir)
if err != nil {
debug.Log("pipe.walk", "Readdirnames(%v) returned error: %v, res %p", dir, err, res)
select {
case <-done:
case jobs <- Dir{basedir: basedir, path: relpath, info: info, error: err, result: res}:
}
return
}
// Insert breakpoint to allow testing behaviour with vanishing files
// between Readdir() and lstat()
debug.RunHook("pipe.walk1", relpath)
entries := make([]<-chan Result, 0, len(names))
for _, name := range names {
subpath := filepath.Join(dir, name)
fi, statErr := os.Lstat(subpath)
if !selectFunc(subpath, fi) {
debug.Log("pipe.walk", "file %v excluded by filter", subpath)
continue
}
ch := make(chan Result, 1)
entries = append(entries, ch)
if statErr != nil {
debug.Log("pipe.walk", "sending file job for %v, err %v, res %p", subpath, err, res)
select {
case jobs <- Entry{info: fi, error: statErr, basedir: basedir, path: filepath.Join(relpath, name), result: ch}:
case <-done:
return
}
continue
}
// Insert breakpoint to allow testing behaviour with vanishing files
// between walk and open
debug.RunHook("pipe.walk2", filepath.Join(relpath, name))
walk(basedir, subpath, selectFunc, done, jobs, ch)
}
debug.Log("pipe.walk", "sending dirjob for %q, basedir %q, res %p", dir, basedir, res)
select {
case jobs <- Dir{basedir: basedir, path: relpath, info: info, Entries: entries, result: res}:
case <-done:
}
return
}
