예제 #1
0
func ldbReplaceWithDelete(db *leveldb.DB, folder, device []byte, fs []protocol.FileInfo) uint64 {
	return ldbGenericReplace(db, folder, device, fs, func(db dbReader, batch dbWriter, folder, device, name []byte, dbi iterator.Iterator) uint64 {
		var tf protocol.FileInfoTruncated
		err := tf.UnmarshalXDR(dbi.Value())
		if err != nil {
			panic(err)
		}
		if !tf.IsDeleted() {
			if debugDB {
				l.Debugf("mark deleted; folder=%q device=%v name=%q", folder, protocol.DeviceIDFromBytes(device), name)
			}
			ts := clock(tf.LocalVersion)
			f := protocol.FileInfo{
				Name:         tf.Name,
				Version:      lamport.Default.Tick(tf.Version),
				LocalVersion: ts,
				Flags:        tf.Flags | protocol.FlagDeleted,
				Modified:     tf.Modified,
			}
			bs, _ := f.MarshalXDR()
			if debugDB {
				l.Debugf("batch.Put %p %x", batch, dbi.Key())
			}
			batch.Put(dbi.Key(), bs)
			ldbUpdateGlobal(db, batch, folder, device, deviceKeyName(dbi.Key()), f.Version)
			return ts
		}
		return 0
	})
}
예제 #2
0
func ldbAvailability(db *leveldb.DB, folder, file []byte) []protocol.DeviceID {
	k := globalKey(folder, file)
	bs, err := db.Get(k, nil)
	if err == leveldb.ErrNotFound {
		return nil
	}
	if err != nil {
		panic(err)
	}

	var vl versionList
	err = vl.UnmarshalXDR(bs)
	if err != nil {
		panic(err)
	}

	var devices []protocol.DeviceID
	for _, v := range vl.versions {
		if v.version != vl.versions[0].version {
			break
		}
		n := protocol.DeviceIDFromBytes(v.device)
		devices = append(devices, n)
	}

	return devices
}
예제 #3
0
// ldbRemoveFromGlobal removes the device from the global version list for the
// given file. If the version list is empty after this, the file entry is
// removed entirely.
func ldbRemoveFromGlobal(db dbReader, batch dbWriter, folder, device, file []byte) {
	if debug {
		l.Debugf("remove from global; folder=%q device=%v file=%q", folder, protocol.DeviceIDFromBytes(device), file)
	}

	gk := globalKey(folder, file)
	svl, err := db.Get(gk, nil)
	if err != nil {
		// We might be called to "remove" a global version that doesn't exist
		// if the first update for the file is already marked invalid.
		return
	}

	var fl versionList
	err = fl.UnmarshalXDR(svl)
	if err != nil {
		panic(err)
	}

	for i := range fl.versions {
		if bytes.Compare(fl.versions[i].device, device) == 0 {
			fl.versions = append(fl.versions[:i], fl.versions[i+1:]...)
			break
		}
	}

	if len(fl.versions) == 0 {
		batch.Delete(gk)
	} else {
		batch.Put(gk, fl.MarshalXDR())
	}
}
예제 #4
0
// ldbUpdateGlobal adds this device+version to the version list for the given
// file. If the device is already present in the list, the version is updated.
// If the file does not have an entry in the global list, it is created.
func ldbUpdateGlobal(db dbReader, batch dbWriter, folder, device, file []byte, version uint64) bool {
	if debugDB {
		l.Debugf("update global; folder=%q device=%v file=%q version=%d", folder, protocol.DeviceIDFromBytes(device), file, version)
	}
	gk := globalKey(folder, file)
	svl, err := db.Get(gk, nil)
	if err != nil && err != leveldb.ErrNotFound {
		panic(err)
	}

	var fl versionList
	nv := fileVersion{
		device:  device,
		version: version,
	}
	if svl != nil {
		err = fl.UnmarshalXDR(svl)
		if err != nil {
			panic(err)
		}

		for i := range fl.versions {
			if bytes.Compare(fl.versions[i].device, device) == 0 {
				if fl.versions[i].version == version {
					// No need to do anything
					return false
				}
				fl.versions = append(fl.versions[:i], fl.versions[i+1:]...)
				break
			}
		}
	}

	for i := range fl.versions {
		if fl.versions[i].version <= version {
			t := append(fl.versions, fileVersion{})
			copy(t[i+1:], t[i:])
			t[i] = nv
			fl.versions = t
			goto done
		}
	}

	fl.versions = append(fl.versions, nv)

done:
	if debugDB {
		l.Debugf("batch.Put %p %x", batch, gk)
		l.Debugf("new global after update: %v", fl)
	}
	batch.Put(gk, fl.MustMarshalXDR())

	return true
}
예제 #5
0
func ldbReplace(db *leveldb.DB, folder, device []byte, fs []protocol.FileInfo) uint64 {
	// TODO: Return the remaining maxLocalVer?
	return ldbGenericReplace(db, folder, device, fs, func(db dbReader, batch dbWriter, folder, device, name []byte, dbi iterator.Iterator) uint64 {
		// Disk has files that we are missing. Remove it.
		if debug {
			l.Debugf("delete; folder=%q device=%v name=%q", folder, protocol.DeviceIDFromBytes(device), name)
		}
		ldbRemoveFromGlobal(db, batch, folder, device, name)
		batch.Delete(dbi.Key())
		return 0
	})
}
예제 #6
0
func ldbInsert(batch dbWriter, folder, device, name []byte, file protocol.FileInfo) uint64 {
	if debug {
		l.Debugf("insert; folder=%q device=%v %v", folder, protocol.DeviceIDFromBytes(device), file)
	}

	if file.LocalVersion == 0 {
		file.LocalVersion = clock(0)
	}

	nk := deviceKey(folder, device, name)
	batch.Put(nk, file.MarshalXDR())

	return file.LocalVersion
}
예제 #7
0
func ldbWithNeed(db *leveldb.DB, folder, device []byte, truncate bool, fn fileIterator) {
	runtime.GC()

	start := globalKey(folder, nil)
	limit := globalKey(folder, []byte{0xff, 0xff, 0xff, 0xff})
	snap, err := db.GetSnapshot()
	if err != nil {
		panic(err)
	}
	if debugDB {
		l.Debugf("created snapshot %p", snap)
	}
	defer func() {
		if debugDB {
			l.Debugf("close snapshot %p", snap)
		}
		snap.Release()
	}()

	dbi := snap.NewIterator(&util.Range{Start: start, Limit: limit}, nil)
	defer dbi.Release()

outer:
	for dbi.Next() {
		var vl versionList
		err := vl.UnmarshalXDR(dbi.Value())
		if err != nil {
			panic(err)
		}
		if len(vl.versions) == 0 {
			l.Debugln(dbi.Key())
			panic("no versions?")
		}

		have := false // If we have the file, any version
		need := false // If we have a lower version of the file
		var haveVersion uint64
		for _, v := range vl.versions {
			if bytes.Compare(v.device, device) == 0 {
				have = true
				haveVersion = v.version
				need = v.version < vl.versions[0].version
				break
			}
		}

		if need || !have {
			name := globalKeyName(dbi.Key())
			needVersion := vl.versions[0].version
		inner:
			for i := range vl.versions {
				if vl.versions[i].version != needVersion {
					// We haven't found a valid copy of the file with the needed version.
					continue outer
				}
				fk := deviceKey(folder, vl.versions[i].device, name)
				if debugDB {
					l.Debugf("snap.Get %p %x", snap, fk)
				}
				bs, err := snap.Get(fk, nil)
				if err != nil {
					var id protocol.DeviceID
					copy(id[:], device)
					l.Debugf("device: %v", id)
					l.Debugf("need: %v, have: %v", need, have)
					l.Debugf("key: %q (%x)", dbi.Key(), dbi.Key())
					l.Debugf("vl: %v", vl)
					l.Debugf("i: %v", i)
					l.Debugf("fk: %q (%x)", fk, fk)
					l.Debugf("name: %q (%x)", name, name)
					panic(err)
				}

				gf, err := unmarshalTrunc(bs, truncate)
				if err != nil {
					panic(err)
				}

				if gf.IsInvalid() {
					// The file is marked invalid for whatever reason, don't use it.
					continue inner
				}

				if gf.IsDeleted() && !have {
					// We don't need deleted files that we don't have
					continue outer
				}

				if debugDB {
					l.Debugf("need folder=%q device=%v name=%q need=%v have=%v haveV=%d globalV=%d", folder, protocol.DeviceIDFromBytes(device), name, need, have, haveVersion, vl.versions[0].version)
				}

				if cont := fn(gf); !cont {
					return
				}

				// This file is handled, no need to look further in the version list
				continue outer
			}
		}
	}
}
예제 #8
0
func ldbGenericReplace(db *leveldb.DB, folder, device []byte, fs []protocol.FileInfo, deleteFn deletionHandler) uint64 {
	runtime.GC()

	sort.Sort(fileList(fs)) // sort list on name, same as in the database

	start := deviceKey(folder, device, nil)                            // before all folder/device files
	limit := deviceKey(folder, device, []byte{0xff, 0xff, 0xff, 0xff}) // after all folder/device files

	batch := new(leveldb.Batch)
	if debugDB {
		l.Debugf("new batch %p", batch)
	}
	snap, err := db.GetSnapshot()
	if err != nil {
		panic(err)
	}
	if debugDB {
		l.Debugf("created snapshot %p", snap)
	}
	defer func() {
		if debugDB {
			l.Debugf("close snapshot %p", snap)
		}
		snap.Release()
	}()

	dbi := snap.NewIterator(&util.Range{Start: start, Limit: limit}, nil)
	defer dbi.Release()

	moreDb := dbi.Next()
	fsi := 0
	var maxLocalVer uint64

	for {
		var newName, oldName []byte
		moreFs := fsi < len(fs)

		if !moreDb && !moreFs {
			break
		}

		if moreFs {
			newName = []byte(fs[fsi].Name)
		}

		if moreDb {
			oldName = deviceKeyName(dbi.Key())
		}

		cmp := bytes.Compare(newName, oldName)

		if debugDB {
			l.Debugf("generic replace; folder=%q device=%v moreFs=%v moreDb=%v cmp=%d newName=%q oldName=%q", folder, protocol.DeviceIDFromBytes(device), moreFs, moreDb, cmp, newName, oldName)
		}

		switch {
		case moreFs && (!moreDb || cmp == -1):
			if debugDB {
				l.Debugln("generic replace; missing - insert")
			}
			// Database is missing this file. Insert it.
			if lv := ldbInsert(batch, folder, device, fs[fsi]); lv > maxLocalVer {
				maxLocalVer = lv
			}
			if fs[fsi].IsInvalid() {
				ldbRemoveFromGlobal(snap, batch, folder, device, newName)
			} else {
				ldbUpdateGlobal(snap, batch, folder, device, newName, fs[fsi].Version)
			}
			fsi++

		case moreFs && moreDb && cmp == 0:
			// File exists on both sides - compare versions. We might get an
			// update with the same version and different flags if a device has
			// marked a file as invalid, so handle that too.
			if debugDB {
				l.Debugln("generic replace; exists - compare")
			}
			var ef protocol.FileInfoTruncated
			ef.UnmarshalXDR(dbi.Value())
			if fs[fsi].Version > ef.Version ||
				(fs[fsi].Version == ef.Version && fs[fsi].Flags != ef.Flags) {
				if debugDB {
					l.Debugln("generic replace; differs - insert")
				}
				if lv := ldbInsert(batch, folder, device, fs[fsi]); lv > maxLocalVer {
					maxLocalVer = lv
				}
				if fs[fsi].IsInvalid() {
					ldbRemoveFromGlobal(snap, batch, folder, device, newName)
				} else {
					ldbUpdateGlobal(snap, batch, folder, device, newName, fs[fsi].Version)
				}
			} else if debugDB {
				l.Debugln("generic replace; equal - ignore")
			}

			fsi++
			moreDb = dbi.Next()

		case moreDb && (!moreFs || cmp == 1):
			if debugDB {
				l.Debugln("generic replace; exists - remove")
			}
			if lv := deleteFn(snap, batch, folder, device, oldName, dbi); lv > maxLocalVer {
				maxLocalVer = lv
			}
			moreDb = dbi.Next()
		}
	}

	if debugDB {
		l.Debugf("db.Write %p", batch)
	}
	err = db.Write(batch, nil)
	if err != nil {
		panic(err)
	}

	return maxLocalVer
}