package storage import ( "bytes" "errors" "fmt" "io" "os" "time" "github.com/chrislusf/seaweedfs/weed/glog" ) // 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 > 0 { oldNeedle := new(Needle) err := oldNeedle.ReadData(v.dataFile, int64(nv.Offset)*NeedlePaddingSize, nv.Size, v.Version()) if err != nil { glog.V(0).Infof("Failed to check updated file %v", err) return false } defer oldNeedle.ReleaseMemory() 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() err = os.Remove(v.dataFile.Name()) if err != nil { return } err = v.nm.Destroy() 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) (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 } var offset int64 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 } } if size, _, err = n.Append(v.dataFile, v.Version()); err != nil { if e := v.dataFile.Truncate(offset); e != nil { err = fmt.Errorf("%s\ncannot truncate %s: %v", err, v.dataFile.Name(), e) } return } nv, ok := v.nm.Get(n.Id) if !ok || int64(nv.Offset)*NeedlePaddingSize < offset { if err = v.nm.Put(n.Id, uint32(offset/NeedlePaddingSize), 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 offset, err := v.dataFile.Seek(0, 2) if err != nil { return size, err } if err := v.nm.Delete(n.Id, uint32(offset/NeedlePaddingSize)); err != nil { return size, err } n.Data = nil _, _, err = n.Append(v.dataFile, v.Version()) 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 == 0 { return -1, errors.New("Not Found") } if nv.Size == TombstoneFileSize { return -1, errors.New("Already Deleted") } err := n.ReadData(v.dataFile, int64(nv.Offset)*NeedlePaddingSize, 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 } n.ReleaseMemory() return -1, errors.New("Not Found") } func ScanVolumeFile(dirname string, collection string, id VolumeId, needleMapKind NeedleMapType, visitSuperBlock func(SuperBlock) error, readNeedleBody bool, visitNeedle func(n *Needle, offset int64) error) (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 = visitSuperBlock(v.SuperBlock); err != nil { return fmt.Errorf("Failed to process volume %d super block: %v", id, err) } version := v.Version() offset := int64(SuperBlockSize) n, rest, e := ReadNeedleHeader(v.dataFile, version, offset) if e != nil { err = fmt.Errorf("cannot read needle header: %v", e) return } for n != nil { if readNeedleBody { if err = n.ReadNeedleBody(v.dataFile, version, offset+int64(NeedleHeaderSize), rest); err != nil { glog.V(0).Infof("cannot read needle body: %v", err) //err = fmt.Errorf("cannot read needle body: %v", err) //return } if n.DataSize >= n.Size { // this should come from a bug reported on #87 and #93 // fixed in v0.69 // remove this whole "if" clause later, long after 0.69 oldRest, oldSize := rest, n.Size padding := NeedlePaddingSize - ((n.Size + NeedleHeaderSize + NeedleChecksumSize) % NeedlePaddingSize) n.Size = 0 rest = n.Size + NeedleChecksumSize + padding if rest%NeedlePaddingSize != 0 { rest += (NeedlePaddingSize - rest%NeedlePaddingSize) } glog.V(4).Infof("Adjusting n.Size %d=>0 rest:%d=>%d %+v", oldSize, oldRest, rest, n) } } if err = visitNeedle(n, offset); err != nil { glog.V(0).Infof("visit needle error: %v", err) } offset += int64(NeedleHeaderSize) + int64(rest) glog.V(4).Infof("==> new entry offset %d", offset) if n, rest, err = ReadNeedleHeader(v.dataFile, version, offset); err != nil { if err == io.EOF { return nil } return fmt.Errorf("cannot read needle header: %v", err) } glog.V(4).Infof("new entry needle size:%d rest:%d", n.Size, rest) } return }