mirror of
https://github.com/syncthing/syncthing.git
synced 2024-11-16 10:28:49 -07:00
80 lines
2.5 KiB
Go
80 lines
2.5 KiB
Go
// Copyright (C) 2015 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 http://mozilla.org/MPL/2.0/.
|
|
|
|
package db
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"fmt"
|
|
"time"
|
|
)
|
|
|
|
// This type encapsulates a repository of mtimes for platforms where file mtimes
|
|
// can't be set to arbitrary values. For this to work, we need to store both
|
|
// the mtime we tried to set (the "actual" mtime) as well as the mtime the file
|
|
// has when we're done touching it (the "disk" mtime) so that we can tell if it
|
|
// was changed. So in GetMtime(), it's not sufficient that the record exists --
|
|
// the argument must also equal the "disk" mtime in the record, otherwise it's
|
|
// been touched locally and the "disk" mtime is actually correct.
|
|
|
|
type VirtualMtimeRepo struct {
|
|
ns *NamespacedKV
|
|
}
|
|
|
|
func NewVirtualMtimeRepo(ldb *Instance, folder string) *VirtualMtimeRepo {
|
|
var prefix [5]byte // key type + 4 bytes folder idx number
|
|
prefix[0] = KeyTypeVirtualMtime
|
|
binary.BigEndian.PutUint32(prefix[1:], ldb.folderIdx.ID([]byte(folder)))
|
|
|
|
return &VirtualMtimeRepo{
|
|
ns: NewNamespacedKV(ldb, string(prefix[:])),
|
|
}
|
|
}
|
|
|
|
func (r *VirtualMtimeRepo) UpdateMtime(path string, diskMtime, actualMtime time.Time) {
|
|
l.Debugf("virtual mtime: storing values for path:%s disk:%v actual:%v", path, diskMtime, actualMtime)
|
|
|
|
diskBytes, _ := diskMtime.MarshalBinary()
|
|
actualBytes, _ := actualMtime.MarshalBinary()
|
|
|
|
data := append(diskBytes, actualBytes...)
|
|
|
|
r.ns.PutBytes(path, data)
|
|
}
|
|
|
|
func (r *VirtualMtimeRepo) GetMtime(path string, diskMtime time.Time) time.Time {
|
|
data, exists := r.ns.Bytes(path)
|
|
if !exists {
|
|
// Absence of debug print is significant enough in itself here
|
|
return diskMtime
|
|
}
|
|
|
|
var mtime time.Time
|
|
if err := mtime.UnmarshalBinary(data[:len(data)/2]); err != nil {
|
|
panic(fmt.Sprintf("Can't unmarshal stored mtime at path %s: %v", path, err))
|
|
}
|
|
|
|
if mtime.Equal(diskMtime) {
|
|
if err := mtime.UnmarshalBinary(data[len(data)/2:]); err != nil {
|
|
panic(fmt.Sprintf("Can't unmarshal stored mtime at path %s: %v", path, err))
|
|
}
|
|
|
|
l.Debugf("virtual mtime: return %v instead of %v for path: %s", mtime, diskMtime, path)
|
|
return mtime
|
|
}
|
|
|
|
l.Debugf("virtual mtime: record exists, but mismatch inDisk: %v dbDisk: %v for path: %s", diskMtime, mtime, path)
|
|
return diskMtime
|
|
}
|
|
|
|
func (r *VirtualMtimeRepo) DeleteMtime(path string) {
|
|
r.ns.Delete(path)
|
|
}
|
|
|
|
func (r *VirtualMtimeRepo) Drop() {
|
|
r.ns.Reset()
|
|
}
|