Example #1
0
// handleFile queues the copies and pulls as necessary for a single new or
// changed file.
func (p *rwFolder) handleFile(file protocol.FileInfo, copyChan chan<- copyBlocksState, finisherChan chan<- *sharedPullerState) {
	curFile, hasCurFile := p.model.CurrentFolderFile(p.folder, file.Name)

	if hasCurFile && len(curFile.Blocks) == len(file.Blocks) && scanner.BlocksEqual(curFile.Blocks, file.Blocks) {
		// We are supposed to copy the entire file, and then fetch nothing. We
		// are only updating metadata, so we don't actually *need* to make the
		// copy.
		l.Debugln(p, "taking shortcut on", file.Name)

		events.Default.Log(events.ItemStarted, map[string]string{
			"folder": p.folder,
			"item":   file.Name,
			"type":   "file",
			"action": "metadata",
		})

		p.queue.Done(file.Name)

		var err error
		if file.IsSymlink() {
			err = p.shortcutSymlink(file)
		} else {
			err = p.shortcutFile(file)
		}

		events.Default.Log(events.ItemFinished, map[string]interface{}{
			"folder": p.folder,
			"item":   file.Name,
			"error":  events.Error(err),
			"type":   "file",
			"action": "metadata",
		})

		if err != nil {
			l.Infoln("Puller: shortcut:", err)
			p.newError(file.Name, err)
		} else {
			p.dbUpdates <- dbUpdateJob{file, dbUpdateShortcutFile}
		}

		return
	}

	// Figure out the absolute filenames we need once and for all
	tempName := filepath.Join(p.dir, defTempNamer.TempName(file.Name))
	realName := filepath.Join(p.dir, file.Name)

	if hasCurFile && !curFile.IsDirectory() && !curFile.IsSymlink() {
		// Check that the file on disk is what we expect it to be according to
		// the database. If there's a mismatch here, there might be local
		// changes that we don't know about yet and we should scan before
		// touching the file. If we can't stat the file we'll just pull it.
		if info, err := osutil.Lstat(realName); err == nil {
			mtime := p.virtualMtimeRepo.GetMtime(file.Name, info.ModTime())
			if mtime.Unix() != curFile.Modified || info.Size() != curFile.Size() {
				l.Debugln("file modified but not rescanned; not pulling:", realName)
				// Scan() is synchronous (i.e. blocks until the scan is
				// completed and returns an error), but a scan can't happen
				// while we're in the puller routine. Request the scan in the
				// background and it'll be handled when the current pulling
				// sweep is complete. As we do retries, we'll queue the scan
				// for this file up to ten times, but the last nine of those
				// scans will be cheap...
				go p.Scan([]string{file.Name})
				return
			}
		}
	}

	scanner.PopulateOffsets(file.Blocks)

	reused := 0
	var blocks []protocol.BlockInfo
	var blocksSize int64

	// Check for an old temporary file which might have some blocks we could
	// reuse.
	tempBlocks, err := scanner.HashFile(tempName, protocol.BlockSize, 0, nil)
	if err == nil {
		// Check for any reusable blocks in the temp file
		tempCopyBlocks, _ := scanner.BlockDiff(tempBlocks, file.Blocks)

		// block.String() returns a string unique to the block
		existingBlocks := make(map[string]struct{}, len(tempCopyBlocks))
		for _, block := range tempCopyBlocks {
			existingBlocks[block.String()] = struct{}{}
		}

		// Since the blocks are already there, we don't need to get them.
		for _, block := range file.Blocks {
			_, ok := existingBlocks[block.String()]
			if !ok {
				blocks = append(blocks, block)
				blocksSize += int64(block.Size)
			}
		}

		// The sharedpullerstate will know which flags to use when opening the
		// temp file depending if we are reusing any blocks or not.
		reused = len(file.Blocks) - len(blocks)
		if reused == 0 {
			// Otherwise, discard the file ourselves in order for the
			// sharedpuller not to panic when it fails to exclusively create a
			// file which already exists
			osutil.InWritableDir(osutil.Remove, tempName)
		}
	} else {
		blocks = file.Blocks
		blocksSize = file.Size()
	}

	if p.checkFreeSpace {
		if free, err := osutil.DiskFreeBytes(p.dir); err == nil && free < blocksSize {
			l.Warnf(`Folder "%s": insufficient disk space in %s for %s: have %.2f MiB, need %.2f MiB`, p.folder, p.dir, file.Name, float64(free)/1024/1024, float64(blocksSize)/1024/1024)
			p.newError(file.Name, errors.New("insufficient space"))
			return
		}
	}

	events.Default.Log(events.ItemStarted, map[string]string{
		"folder": p.folder,
		"item":   file.Name,
		"type":   "file",
		"action": "update",
	})

	s := sharedPullerState{
		file:        file,
		folder:      p.folder,
		tempName:    tempName,
		realName:    realName,
		copyTotal:   len(blocks),
		copyNeeded:  len(blocks),
		reused:      reused,
		ignorePerms: p.ignorePermissions(file),
		version:     curFile.Version,
		mut:         sync.NewMutex(),
		sparse:      p.allowSparse,
	}

	l.Debugf("%v need file %s; copy %d, reused %v", p, file.Name, len(blocks), reused)

	cs := copyBlocksState{
		sharedPullerState: &s,
		blocks:            blocks,
	}
	copyChan <- cs
}
Example #2
0
// pullerIteration runs a single puller iteration for the given folder and
// returns the number items that should have been synced (even those that
// might have failed). One puller iteration handles all files currently
// flagged as needed in the folder.
func (p *rwFolder) pullerIteration(ignores *ignore.Matcher) int {
	pullChan := make(chan pullBlockState)
	copyChan := make(chan copyBlocksState)
	finisherChan := make(chan *sharedPullerState)

	updateWg := sync.NewWaitGroup()
	copyWg := sync.NewWaitGroup()
	pullWg := sync.NewWaitGroup()
	doneWg := sync.NewWaitGroup()

	l.Debugln(p, "c", p.copiers, "p", p.pullers)

	p.dbUpdates = make(chan dbUpdateJob)
	updateWg.Add(1)
	go func() {
		// dbUpdaterRoutine finishes when p.dbUpdates is closed
		p.dbUpdaterRoutine()
		updateWg.Done()
	}()

	for i := 0; i < p.copiers; i++ {
		copyWg.Add(1)
		go func() {
			// copierRoutine finishes when copyChan is closed
			p.copierRoutine(copyChan, pullChan, finisherChan)
			copyWg.Done()
		}()
	}

	for i := 0; i < p.pullers; i++ {
		pullWg.Add(1)
		go func() {
			// pullerRoutine finishes when pullChan is closed
			p.pullerRoutine(pullChan, finisherChan)
			pullWg.Done()
		}()
	}

	doneWg.Add(1)
	// finisherRoutine finishes when finisherChan is closed
	go func() {
		p.finisherRoutine(finisherChan)
		doneWg.Done()
	}()

	p.model.fmut.RLock()
	folderFiles := p.model.folderFiles[p.folder]
	p.model.fmut.RUnlock()

	// !!!
	// WithNeed takes a database snapshot (by necessity). By the time we've
	// handled a bunch of files it might have become out of date and we might
	// be attempting to sync with an old version of a file...
	// !!!

	changed := 0

	fileDeletions := map[string]protocol.FileInfo{}
	dirDeletions := []protocol.FileInfo{}
	buckets := map[string][]protocol.FileInfo{}

	handleFile := func(f protocol.FileInfo) bool {
		switch {
		case f.IsDeleted():
			// A deleted file, directory or symlink
			if f.IsDirectory() {
				dirDeletions = append(dirDeletions, f)
			} else {
				fileDeletions[f.Name] = f
				df, ok := p.model.CurrentFolderFile(p.folder, f.Name)
				// Local file can be already deleted, but with a lower version
				// number, hence the deletion coming in again as part of
				// WithNeed, furthermore, the file can simply be of the wrong
				// type if we haven't yet managed to pull it.
				if ok && !df.IsDeleted() && !df.IsSymlink() && !df.IsDirectory() {
					// Put files into buckets per first hash
					key := string(df.Blocks[0].Hash)
					buckets[key] = append(buckets[key], df)
				}
			}
		case f.IsDirectory() && !f.IsSymlink():
			// A new or changed directory
			l.Debugln("Creating directory", f.Name)
			p.handleDir(f)
		default:
			return false
		}
		return true
	}

	folderFiles.WithNeed(protocol.LocalDeviceID, func(intf db.FileIntf) bool {
		// Needed items are delivered sorted lexicographically. We'll handle
		// directories as they come along, so parents before children. Files
		// are queued and the order may be changed later.

		file := intf.(protocol.FileInfo)

		if ignores.Match(file.Name) {
			// This is an ignored file. Skip it, continue iteration.
			return true
		}

		l.Debugln(p, "handling", file.Name)

		if !handleFile(file) {
			// A new or changed file or symlink. This is the only case where we
			// do stuff concurrently in the background
			p.queue.Push(file.Name, file.Size(), file.Modified)
		}

		changed++
		return true
	})

	// Reorder the file queue according to configuration

	switch p.order {
	case config.OrderRandom:
		p.queue.Shuffle()
	case config.OrderAlphabetic:
		// The queue is already in alphabetic order.
	case config.OrderSmallestFirst:
		p.queue.SortSmallestFirst()
	case config.OrderLargestFirst:
		p.queue.SortLargestFirst()
	case config.OrderOldestFirst:
		p.queue.SortOldestFirst()
	case config.OrderNewestFirst:
		p.queue.SortNewestFirst()
	}

	// Process the file queue

nextFile:
	for {
		select {
		case <-p.stop:
			// Stop processing files if the puller has been told to stop.
			break
		default:
		}

		fileName, ok := p.queue.Pop()
		if !ok {
			break
		}

		f, ok := p.model.CurrentGlobalFile(p.folder, fileName)
		if !ok {
			// File is no longer in the index. Mark it as done and drop it.
			p.queue.Done(fileName)
			continue
		}

		// Handles races where an index update arrives changing what the file
		// is between queueing and retrieving it from the queue, effectively
		// changing how the file should be handled.
		if handleFile(f) {
			continue
		}

		if !f.IsSymlink() {
			key := string(f.Blocks[0].Hash)
			for i, candidate := range buckets[key] {
				if scanner.BlocksEqual(candidate.Blocks, f.Blocks) {
					// Remove the candidate from the bucket
					lidx := len(buckets[key]) - 1
					buckets[key][i] = buckets[key][lidx]
					buckets[key] = buckets[key][:lidx]

					// candidate is our current state of the file, where as the
					// desired state with the delete bit set is in the deletion
					// map.
					desired := fileDeletions[candidate.Name]
					// Remove the pending deletion (as we perform it by renaming)
					delete(fileDeletions, candidate.Name)

					p.renameFile(desired, f)

					p.queue.Done(fileName)
					continue nextFile
				}
			}
		}

		// Not a rename or a symlink, deal with it.
		p.handleFile(f, copyChan, finisherChan)
	}

	// Signal copy and puller routines that we are done with the in data for
	// this iteration. Wait for them to finish.
	close(copyChan)
	copyWg.Wait()
	close(pullChan)
	pullWg.Wait()

	// Signal the finisher chan that there will be no more input.
	close(finisherChan)

	// Wait for the finisherChan to finish.
	doneWg.Wait()

	for _, file := range fileDeletions {
		l.Debugln("Deleting file", file.Name)
		p.deleteFile(file)
	}

	for i := range dirDeletions {
		dir := dirDeletions[len(dirDeletions)-i-1]
		l.Debugln("Deleting dir", dir.Name)
		p.deleteDir(dir)
	}

	// Wait for db updates to complete
	close(p.dbUpdates)
	updateWg.Wait()

	return changed
}