package storage import ( "bytes" "errors" "fmt" "io" "os" "time" "github.com/chrislusf/seaweedfs/weed/glog" . "github.com/chrislusf/seaweedfs/weed/storage/types" ) var ErrorNotFound = errors.New("not found") // isFileUnchanged checks whether this needle to write is same as last one. // It requires serialized access in the same volume. func (v *Volume) isFileUnchanged(n *Needle) bool { if v.Ttl.String() != "" { return false } nv, ok := v.nm.Get(n.Id) if ok && !nv.Offset.IsZero() { oldNeedle := new(Needle) err := oldNeedle.ReadData(v.dataFile, nv.Offset.ToAcutalOffset(), nv.Size, v.Version()) if err != nil { glog.V(0).Infof("Failed to check updated file %v", err) return false } if oldNeedle.Checksum == n.Checksum && bytes.Equal(oldNeedle.Data, n.Data) { n.DataSize = oldNeedle.DataSize return true } } return false } // Destroy removes everything related to this volume func (v *Volume) Destroy() (err error) { if v.readOnly { err = fmt.Errorf("%s is read-only", v.dataFile.Name()) return } v.Close() os.Remove(v.FileName() + ".dat") os.Remove(v.FileName() + ".idx") os.Remove(v.FileName() + ".cpd") os.Remove(v.FileName() + ".cpx") os.Remove(v.FileName() + ".ldb") os.Remove(v.FileName() + ".bdb") return } // AppendBlob append a blob to end of the data file, used in replication func (v *Volume) AppendBlob(b []byte) (offset int64, err error) { if v.readOnly { err = fmt.Errorf("%s is read-only", v.dataFile.Name()) return } v.dataFileAccessLock.Lock() defer v.dataFileAccessLock.Unlock() if offset, err = v.dataFile.Seek(0, 2); err != nil { glog.V(0).Infof("failed to seek the end of file: %v", err) return } //ensure file writing starting from aligned positions if offset%NeedlePaddingSize != 0 { offset = offset + (NeedlePaddingSize - offset%NeedlePaddingSize) if offset, err = v.dataFile.Seek(offset, 0); err != nil { glog.V(0).Infof("failed to align in datafile %s: %v", v.dataFile.Name(), err) return } } _, err = v.dataFile.Write(b) return } func (v *Volume) writeNeedle(n *Needle) (offset uint64, size uint32, err error) { glog.V(4).Infof("writing needle %s", NewFileIdFromNeedle(v.Id, n).String()) if v.readOnly { err = fmt.Errorf("%s is read-only", v.dataFile.Name()) return } v.dataFileAccessLock.Lock() defer v.dataFileAccessLock.Unlock() if v.isFileUnchanged(n) { size = n.DataSize glog.V(4).Infof("needle is unchanged!") return } n.AppendAtNs = uint64(time.Now().UnixNano()) if offset, size, _, err = n.Append(v.dataFile, v.Version()); err != nil { return } nv, ok := v.nm.Get(n.Id) if !ok || uint64(nv.Offset.ToAcutalOffset()) < offset { if err = v.nm.Put(n.Id, ToOffset(int64(offset)), n.Size); err != nil { glog.V(4).Infof("failed to save in needle map %d: %v", n.Id, err) } } if v.lastModifiedTime < n.LastModified { v.lastModifiedTime = n.LastModified } return } func (v *Volume) deleteNeedle(n *Needle) (uint32, error) { glog.V(4).Infof("delete needle %s", NewFileIdFromNeedle(v.Id, n).String()) if v.readOnly { return 0, fmt.Errorf("%s is read-only", v.dataFile.Name()) } v.dataFileAccessLock.Lock() defer v.dataFileAccessLock.Unlock() nv, ok := v.nm.Get(n.Id) //fmt.Println("key", n.Id, "volume offset", nv.Offset, "data_size", n.Size, "cached size", nv.Size) if ok && nv.Size != TombstoneFileSize { size := nv.Size n.Data = nil n.AppendAtNs = uint64(time.Now().UnixNano()) offset, _, _, err := n.Append(v.dataFile, v.Version()) if err != nil { return size, err } if err = v.nm.Delete(n.Id, ToOffset(int64(offset))); err != nil { return size, err } return size, err } return 0, nil } // read fills in Needle content by looking up n.Id from NeedleMapper func (v *Volume) readNeedle(n *Needle) (int, error) { nv, ok := v.nm.Get(n.Id) if !ok || nv.Offset.IsZero() { v.compactingWg.Wait() nv, ok = v.nm.Get(n.Id) if !ok || nv.Offset.IsZero() { return -1, ErrorNotFound } } if nv.Size == TombstoneFileSize { return -1, errors.New("already deleted") } if nv.Size == 0 { return 0, nil } err := n.ReadData(v.dataFile, nv.Offset.ToAcutalOffset(), nv.Size, v.Version()) if err != nil { return 0, err } bytesRead := len(n.Data) if !n.HasTtl() { return bytesRead, nil } ttlMinutes := n.Ttl.Minutes() if ttlMinutes == 0 { return bytesRead, nil } if !n.HasLastModifiedDate() { return bytesRead, nil } if uint64(time.Now().Unix()) < n.LastModified+uint64(ttlMinutes*60) { return bytesRead, nil } return -1, ErrorNotFound } type VolumeFileScanner interface { VisitSuperBlock(SuperBlock) error ReadNeedleBody() bool VisitNeedle(n *Needle, offset int64) error } func ScanVolumeFile(dirname string, collection string, id VolumeId, needleMapKind NeedleMapType, volumeFileScanner VolumeFileScanner) (err error) { var v *Volume if v, err = loadVolumeWithoutIndex(dirname, collection, id, needleMapKind); err != nil { return fmt.Errorf("failed to load volume %d: %v", id, err) } if err = volumeFileScanner.VisitSuperBlock(v.SuperBlock); err != nil { return fmt.Errorf("failed to process volume %d super block: %v", id, err) } defer v.Close() version := v.Version() offset := int64(v.SuperBlock.BlockSize()) return ScanVolumeFileFrom(version, v.dataFile, offset, volumeFileScanner) } func ScanVolumeFileFrom(version Version, dataFile *os.File, offset int64, volumeFileScanner VolumeFileScanner) (err error) { n, rest, e := ReadNeedleHeader(dataFile, version, offset) if e != nil { if e == io.EOF { return nil } return fmt.Errorf("cannot read %s at offset %d: %v", dataFile.Name(), offset, e) } for n != nil { if volumeFileScanner.ReadNeedleBody() { if err = n.ReadNeedleBody(dataFile, version, offset+NeedleEntrySize, rest); err != nil { glog.V(0).Infof("cannot read needle body: %v", err) //err = fmt.Errorf("cannot read needle body: %v", err) //return } } err := volumeFileScanner.VisitNeedle(n, offset) if err == io.EOF { return nil } if err != nil { glog.V(0).Infof("visit needle error: %v", err) } offset += NeedleEntrySize + rest glog.V(4).Infof("==> new entry offset %d", offset) if n, rest, err = ReadNeedleHeader(dataFile, version, offset); err != nil { if err == io.EOF { return nil } return fmt.Errorf("cannot read needle header at offset %d: %v", offset, err) } glog.V(4).Infof("new entry needle size:%d rest:%d", n.Size, rest) } return nil }