func (m cdbMap) Visit(visit func(NeedleValue) error) (err error) { fh, err := os.Open(m.fn1) if err != nil { return fmt.Errorf("cannot open %s: %s", m.fn1, err) } defer fh.Close() walk := func(elt cdb.Element) error { if len(elt.Key) != 8 { return nil } return visit(NeedleValue{Key: Key(util.BytesToUint64(elt.Key)), Offset: util.BytesToUint32(elt.Data[:4]), Size: util.BytesToUint32(elt.Data[4:8])}) } if err = cdb.DumpMap(fh, walk); err != nil { return err } //只有一张表 if m.c2 == nil { return nil } fh.Close() if fh, err = os.Open(m.fn2); err != nil { return fmt.Errorf("cannot open %s: %s", m.fn2, err) } return cdb.DumpMap(fh, walk) }
func LoadNewNeedleMap(file *os.File) CompactMap { m := NewCompactMap() bytes := make([]byte, 16*1024) count, e := file.Read(bytes) if count > 0 { fstat, _ := file.Stat() glog.V(0).Infoln("Loading index file", fstat.Name(), "size", fstat.Size()) } for count > 0 && e == nil { for i := 0; i < count; i += 16 { key := util.BytesToUint64(bytes[i : i+8]) offset := util.BytesToUint32(bytes[i+8 : i+12]) size := util.BytesToUint32(bytes[i+12 : i+16]) if offset > 0 { m.Set(Key(key), offset, size) } else { //delete(m, key) } } count, e = file.Read(bytes) } return m }
func (n *Needle) readNeedleDataVersion2(bytes []byte) { index, lenBytes := 0, len(bytes) if index < lenBytes { n.DataSize = util.BytesToUint32(bytes[index : index+4]) index = index + 4 n.Data = bytes[index : index+int(n.DataSize)] index = index + int(n.DataSize) n.Flags = bytes[index] index = index + 1 } if index < lenBytes && n.HasName() { n.NameSize = uint8(bytes[index]) index = index + 1 n.Name = bytes[index : index+int(n.NameSize)] index = index + int(n.NameSize) } if index < lenBytes && n.HasMime() { n.MimeSize = uint8(bytes[index]) index = index + 1 n.Mime = bytes[index : index+int(n.MimeSize)] index = index + int(n.MimeSize) } if index < lenBytes && n.HasLastModifiedDate() { n.LastModified = util.BytesToUint64(bytes[index : index+LastModifiedBytesLength]) index = index + LastModifiedBytesLength } if index < lenBytes && n.HasTtl() { n.Ttl = LoadTTLFromBytes(bytes[index : index+TtlBytesLength]) index = index + TtlBytesLength } }
func (n *Needle) Read(r *os.File, offset int64, size uint32, version Version) (ret int, err error) { switch version { case Version1: bytes := make([]byte, NeedleHeaderSize+size+NeedleChecksumSize) if ret, err = r.ReadAt(bytes, offset); err != nil { return } n.readNeedleHeader(bytes) n.Data = bytes[NeedleHeaderSize : NeedleHeaderSize+size] checksum := util.BytesToUint32(bytes[NeedleHeaderSize+size : NeedleHeaderSize+size+NeedleChecksumSize]) newChecksum := NewCRC(n.Data) if checksum != newChecksum.Value() { return 0, errors.New("CRC error! Data On Disk Corrupted!") } n.Checksum = newChecksum return case Version2: if size == 0 { return 0, nil } bytes := make([]byte, NeedleHeaderSize+size+NeedleChecksumSize) if ret, err = r.ReadAt(bytes, offset); err != nil { return } if ret != int(NeedleHeaderSize+size+NeedleChecksumSize) { return 0, errors.New("File Entry Not Found!") } n.readNeedleHeader(bytes) if n.Size != size { return 0, fmt.Errorf("File Entry Not Found! Needle %d Memory %d", n.Size, size) } n.readNeedleDataVersion2(bytes[NeedleHeaderSize : NeedleHeaderSize+int(n.Size)]) checksum := util.BytesToUint32(bytes[NeedleHeaderSize+n.Size : NeedleHeaderSize+n.Size+NeedleChecksumSize]) newChecksum := NewCRC(n.Data) if checksum != newChecksum.Value() { return 0, errors.New("CRC error! Data On Disk Corrupted!") } n.Checksum = newChecksum return } return 0, fmt.Errorf("Unsupported Version! (%d)", version) }
func (m cdbMap) Get(key uint64) (element *NeedleValue, ok bool) { var ( data []byte k []byte = make([]byte, 8) err error ) util.Uint64toBytes(k, key) //优先从c1读取,如果失败则尝试读c2,因为每个表只能存储有限数量的records if data, err = m.c1.Data(k); err != nil || data == nil { if m.c2 == nil { return nil, false } if data, err = m.c2.Data(k); err != nil || data == nil { return nil, false } } return &NeedleValue{Key: Key(key), Offset: util.BytesToUint32(data[:4]), Size: util.BytesToUint32(data[4:])}, true }
func ParseKeyHash(key_hash_string string) (uint64, uint32, error) { key_hash_bytes, khe := hex.DecodeString(key_hash_string) key_hash_len := len(key_hash_bytes) if khe != nil || key_hash_len <= 4 { glog.V(0).Infoln("Invalid key_hash", key_hash_string, "length:", key_hash_len, "error", khe) return 0, 0, errors.New("Invalid key and hash:" + key_hash_string) } key := util.BytesToUint64(key_hash_bytes[0 : key_hash_len-4]) hash := util.BytesToUint32(key_hash_bytes[key_hash_len-4 : key_hash_len]) return key, hash, nil }
func (n *Needle) readNeedleHeader(bytes []byte) { n.Cookie = util.BytesToUint32(bytes[0:4]) n.Id = util.BytesToUint64(bytes[4:12]) n.Size = util.BytesToUint32(bytes[12:NeedleHeaderSize]) }