func LoadNeedleMap(file *os.File) *NeedleMap {
nm := NewNeedleMap(file)
bytes := make([]byte, 16*RowsToRead)
count, e := nm.indexFile.Read(bytes)
if count > 0 {
fstat, _ := file.Stat()
log.Println("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 {
nm.m.Set(Key(key), offset, size)
//log.Println("reading key", key, "offset", offset, "size", size)
nm.fileCounter++
} else {
nm.m.Delete(Key(key))
//log.Println("removing key", key)
nm.deletionCounter++
}
}
count, e = nm.indexFile.Read(bytes)
}
return nm
}
func (n *Needle) Read(r io.Reader, size uint32) (int, error) {
bytes := make([]byte, size+16+4)
ret, e := r.Read(bytes)
n.Cookie = util.BytesToUint32(bytes[0:4])
n.Id = util.BytesToUint64(bytes[4:12])
n.Size = util.BytesToUint32(bytes[12:16])
n.Data = bytes[16 : 16+size]
checksum := util.BytesToUint32(bytes[16+size : 16+size+4])
if checksum != NewCRC(n.Data).Value() {
return 0, errors.New("CRC error! Data On Disk Corrupted!")
}
return ret, e
}
func ReadNeedle(r *os.File) (*Needle, uint32) {
n := new(Needle)
bytes := make([]byte, 16)
count, e := r.Read(bytes)
if count <= 0 || e != nil {
return nil, 0
}
n.Cookie = util.BytesToUint32(bytes[0:4])
n.Id = util.BytesToUint64(bytes[4:12])
n.Size = util.BytesToUint32(bytes[12:16])
rest := 8 - ((n.Size + 16 + 4) % 8)
return n, n.Size + 4 + rest
}
func ParseKeyHash(key_hash_string string) (uint64, uint32) {
key_hash_bytes, khe := hex.DecodeString(key_hash_string)
key_hash_len := len(key_hash_bytes)
if khe != nil || key_hash_len <= 4 {
println("Invalid key_hash", key_hash_string, "length:", key_hash_len, "error", khe)
return 0, 0
}
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
}