syncthing/lib/db/set.go
2017-02-09 08:04:16 +01:00

367 lines
10 KiB
Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
// Package db provides a set type to track local/remote files with newness
// checks. We must do a certain amount of normalization in here. We will get
// fed paths with either native or wire-format separators and encodings
// depending on who calls us. We transform paths to wire-format (NFC and
// slashes) on the way to the database, and transform to native format
// (varying separator and encoding) on the way back out.
package db
import (
stdsync "sync"
"sync/atomic"
"github.com/syncthing/syncthing/lib/fs"
"github.com/syncthing/syncthing/lib/osutil"
"github.com/syncthing/syncthing/lib/protocol"
"github.com/syncthing/syncthing/lib/sync"
)
type FileSet struct {
sequence int64 // Our local sequence number
folder string
db *Instance
blockmap *BlockMap
localSize sizeTracker
globalSize sizeTracker
remoteSequence map[protocol.DeviceID]int64 // Highest seen sequence numbers for other devices
updateMutex sync.Mutex // protects remoteSequence and database updates
}
// FileIntf is the set of methods implemented by both protocol.FileInfo and
// FileInfoTruncated.
type FileIntf interface {
FileSize() int64
FileName() string
IsDeleted() bool
IsInvalid() bool
IsDirectory() bool
IsSymlink() bool
HasPermissionBits() bool
}
// The Iterator is called with either a protocol.FileInfo or a
// FileInfoTruncated (depending on the method) and returns true to
// continue iteration, false to stop.
type Iterator func(f FileIntf) bool
type Counts struct {
Files int
Directories int
Symlinks int
Deleted int
Bytes int64
}
type sizeTracker struct {
Counts
mut stdsync.Mutex
}
func (s *sizeTracker) addFile(f FileIntf) {
if f.IsInvalid() {
return
}
s.mut.Lock()
switch {
case f.IsDeleted():
s.Deleted++
case f.IsDirectory() && !f.IsSymlink():
s.Directories++
case f.IsSymlink():
s.Symlinks++
default:
s.Files++
}
s.Bytes += f.FileSize()
s.mut.Unlock()
}
func (s *sizeTracker) removeFile(f FileIntf) {
if f.IsInvalid() {
return
}
s.mut.Lock()
switch {
case f.IsDeleted():
s.Deleted--
case f.IsDirectory() && !f.IsSymlink():
s.Directories--
case f.IsSymlink():
s.Symlinks--
default:
s.Files--
}
s.Bytes -= f.FileSize()
if s.Deleted < 0 || s.Files < 0 || s.Directories < 0 || s.Symlinks < 0 {
panic("bug: removed more than added")
}
s.mut.Unlock()
}
func (s *sizeTracker) Size() Counts {
s.mut.Lock()
defer s.mut.Unlock()
return s.Counts
}
func NewFileSet(folder string, db *Instance) *FileSet {
var s = FileSet{
remoteSequence: make(map[protocol.DeviceID]int64),
folder: folder,
db: db,
blockmap: NewBlockMap(db, db.folderIdx.ID([]byte(folder))),
updateMutex: sync.NewMutex(),
}
s.db.checkGlobals([]byte(folder), &s.globalSize)
var deviceID protocol.DeviceID
s.db.withAllFolderTruncated([]byte(folder), func(device []byte, f FileInfoTruncated) bool {
copy(deviceID[:], device)
if deviceID == protocol.LocalDeviceID {
if f.Sequence > s.sequence {
s.sequence = f.Sequence
}
s.localSize.addFile(f)
} else if f.Sequence > s.remoteSequence[deviceID] {
s.remoteSequence[deviceID] = f.Sequence
}
return true
})
l.Debugf("loaded sequence for %q: %#v", folder, s.sequence)
return &s
}
func (s *FileSet) Replace(device protocol.DeviceID, fs []protocol.FileInfo) {
l.Debugf("%s Replace(%v, [%d])", s.folder, device, len(fs))
normalizeFilenames(fs)
s.updateMutex.Lock()
defer s.updateMutex.Unlock()
if device == protocol.LocalDeviceID {
if len(fs) == 0 {
s.sequence = 0
} else {
// Always overwrite Sequence on updated files to ensure
// correct ordering. The caller is supposed to leave it set to
// zero anyhow.
for i := range fs {
fs[i].Sequence = atomic.AddInt64(&s.sequence, 1)
}
}
} else {
s.remoteSequence[device] = maxSequence(fs)
}
s.db.replace([]byte(s.folder), device[:], fs, &s.localSize, &s.globalSize)
if device == protocol.LocalDeviceID {
s.blockmap.Drop()
s.blockmap.Add(fs)
}
}
func (s *FileSet) Update(device protocol.DeviceID, fs []protocol.FileInfo) {
l.Debugf("%s Update(%v, [%d])", s.folder, device, len(fs))
normalizeFilenames(fs)
s.updateMutex.Lock()
defer s.updateMutex.Unlock()
if device == protocol.LocalDeviceID {
discards := make([]protocol.FileInfo, 0, len(fs))
updates := make([]protocol.FileInfo, 0, len(fs))
for i, newFile := range fs {
fs[i].Sequence = atomic.AddInt64(&s.sequence, 1)
existingFile, ok := s.db.getFile([]byte(s.folder), device[:], []byte(newFile.Name))
if !ok || !existingFile.Version.Equal(newFile.Version) {
discards = append(discards, existingFile)
updates = append(updates, newFile)
}
}
s.blockmap.Discard(discards)
s.blockmap.Update(updates)
} else {
s.remoteSequence[device] = maxSequence(fs)
}
s.db.updateFiles([]byte(s.folder), device[:], fs, &s.localSize, &s.globalSize)
}
func (s *FileSet) WithNeed(device protocol.DeviceID, fn Iterator) {
l.Debugf("%s WithNeed(%v)", s.folder, device)
s.db.withNeed([]byte(s.folder), device[:], false, nativeFileIterator(fn))
}
func (s *FileSet) WithNeedTruncated(device protocol.DeviceID, fn Iterator) {
l.Debugf("%s WithNeedTruncated(%v)", s.folder, device)
s.db.withNeed([]byte(s.folder), device[:], true, nativeFileIterator(fn))
}
func (s *FileSet) WithHave(device protocol.DeviceID, fn Iterator) {
l.Debugf("%s WithHave(%v)", s.folder, device)
s.db.withHave([]byte(s.folder), device[:], nil, false, nativeFileIterator(fn))
}
func (s *FileSet) WithHaveTruncated(device protocol.DeviceID, fn Iterator) {
l.Debugf("%s WithHaveTruncated(%v)", s.folder, device)
s.db.withHave([]byte(s.folder), device[:], nil, true, nativeFileIterator(fn))
}
func (s *FileSet) WithPrefixedHaveTruncated(device protocol.DeviceID, prefix string, fn Iterator) {
l.Debugf("%s WithPrefixedHaveTruncated(%v)", s.folder, device)
s.db.withHave([]byte(s.folder), device[:], []byte(osutil.NormalizedFilename(prefix)), true, nativeFileIterator(fn))
}
func (s *FileSet) WithGlobal(fn Iterator) {
l.Debugf("%s WithGlobal()", s.folder)
s.db.withGlobal([]byte(s.folder), nil, false, nativeFileIterator(fn))
}
func (s *FileSet) WithGlobalTruncated(fn Iterator) {
l.Debugf("%s WithGlobalTruncated()", s.folder)
s.db.withGlobal([]byte(s.folder), nil, true, nativeFileIterator(fn))
}
func (s *FileSet) WithPrefixedGlobalTruncated(prefix string, fn Iterator) {
l.Debugf("%s WithPrefixedGlobalTruncated()", s.folder, prefix)
s.db.withGlobal([]byte(s.folder), []byte(osutil.NormalizedFilename(prefix)), true, nativeFileIterator(fn))
}
func (s *FileSet) Get(device protocol.DeviceID, file string) (protocol.FileInfo, bool) {
f, ok := s.db.getFile([]byte(s.folder), device[:], []byte(osutil.NormalizedFilename(file)))
f.Name = osutil.NativeFilename(f.Name)
return f, ok
}
func (s *FileSet) GetGlobal(file string) (protocol.FileInfo, bool) {
fi, ok := s.db.getGlobal([]byte(s.folder), []byte(osutil.NormalizedFilename(file)), false)
if !ok {
return protocol.FileInfo{}, false
}
f := fi.(protocol.FileInfo)
f.Name = osutil.NativeFilename(f.Name)
return f, true
}
func (s *FileSet) GetGlobalTruncated(file string) (FileInfoTruncated, bool) {
fi, ok := s.db.getGlobal([]byte(s.folder), []byte(osutil.NormalizedFilename(file)), true)
if !ok {
return FileInfoTruncated{}, false
}
f := fi.(FileInfoTruncated)
f.Name = osutil.NativeFilename(f.Name)
return f, true
}
func (s *FileSet) Availability(file string) []protocol.DeviceID {
return s.db.availability([]byte(s.folder), []byte(osutil.NormalizedFilename(file)))
}
func (s *FileSet) Sequence(device protocol.DeviceID) int64 {
if device == protocol.LocalDeviceID {
return atomic.LoadInt64(&s.sequence)
}
s.updateMutex.Lock()
defer s.updateMutex.Unlock()
return s.remoteSequence[device]
}
func (s *FileSet) LocalSize() Counts {
return s.localSize.Size()
}
func (s *FileSet) GlobalSize() Counts {
return s.globalSize.Size()
}
func (s *FileSet) IndexID(device protocol.DeviceID) protocol.IndexID {
id := s.db.getIndexID(device[:], []byte(s.folder))
if id == 0 && device == protocol.LocalDeviceID {
// No index ID set yet. We create one now.
id = protocol.NewIndexID()
s.db.setIndexID(device[:], []byte(s.folder), id)
}
return id
}
func (s *FileSet) SetIndexID(device protocol.DeviceID, id protocol.IndexID) {
if device == protocol.LocalDeviceID {
panic("do not explicitly set index ID for local device")
}
s.db.setIndexID(device[:], []byte(s.folder), id)
}
func (s *FileSet) MtimeFS() *fs.MtimeFS {
prefix := s.db.mtimesKey([]byte(s.folder))
kv := NewNamespacedKV(s.db, string(prefix))
return fs.NewMtimeFS(kv)
}
func (s *FileSet) ListDevices() []protocol.DeviceID {
s.updateMutex.Lock()
devices := make([]protocol.DeviceID, 0, len(s.remoteSequence))
for id, seq := range s.remoteSequence {
if seq > 0 {
devices = append(devices, id)
}
}
s.updateMutex.Unlock()
return devices
}
// maxSequence returns the highest of the Sequence numbers found in
// the given slice of FileInfos. This should really be the Sequence of
// the last item, but Syncthing v0.14.0 and other implementations may not
// implement update sorting....
func maxSequence(fs []protocol.FileInfo) int64 {
var max int64
for _, f := range fs {
if f.Sequence > max {
max = f.Sequence
}
}
return max
}
// DropFolder clears out all information related to the given folder from the
// database.
func DropFolder(db *Instance, folder string) {
db.dropFolder([]byte(folder))
db.dropMtimes([]byte(folder))
bm := &BlockMap{
db: db,
folder: db.folderIdx.ID([]byte(folder)),
}
bm.Drop()
}
func normalizeFilenames(fs []protocol.FileInfo) {
for i := range fs {
fs[i].Name = osutil.NormalizedFilename(fs[i].Name)
}
}
func nativeFileIterator(fn Iterator) Iterator {
return func(fi FileIntf) bool {
switch f := fi.(type) {
case protocol.FileInfo:
f.Name = osutil.NativeFilename(f.Name)
return fn(f)
case FileInfoTruncated:
f.Name = osutil.NativeFilename(f.Name)
return fn(f)
default:
panic("unknown interface type")
}
}
}