Revert "add CdbMap"

This reverts commit bf0ccf3461.
This commit is contained in:
Chris Lu 2013-01-17 00:15:01 -08:00
parent 5b49065a57
commit d1494ea786
4 changed files with 32 additions and 195 deletions

View file

@ -1,107 +0,0 @@
package storage
import (
"github.com/tgulacsi/go-cdb"
"io"
"log"
"os"
"pkg/util"
"strings"
)
type CdbMap struct {
db *cdb.Cdb
transient []byte
Filename string
}
// Opens the CDB file and servers as a needle map
func NewCdbMap(filename string) (*CdbMap, error) {
m, err := cdb.Open(filename)
if err != nil {
return nil, err
}
return &CdbMap{db: m, transient: make([]byte, 8),
Filename: filename}, nil
}
// writes the content of the index file to a CDB and returns that
func NewCdbMapFromIndex(indexFile *os.File) (*CdbMap, error) {
nm := indexFile.Name()
nm = nm[strings.LastIndex(nm, ".")+1:] + "cdb"
var (
key uint64
offset uint32
ok bool
)
deleted := make(map[uint64]bool, 16)
gatherDeletes := func(buf []byte) error {
key = util.BytesToUint64(buf[:8])
offset = util.BytesToUint32(buf[8:12])
if offset > 0 {
if _, ok = deleted[key]; ok { //undelete
delete(deleted, key)
}
} else {
deleted[key] = true
}
return nil
}
if err := readIndexFile(indexFile, gatherDeletes); err != nil {
return nil, err
}
w, err := cdb.NewWriter(nm)
if err != nil {
return nil, err
}
iterFun := func(buf []byte) error {
key = util.BytesToUint64(buf[:8])
if _, ok = deleted[key]; !ok {
w.PutPair(buf[:8], buf[8:16])
}
return nil
}
indexFile.Seek(0, 0)
err = readIndexFile(indexFile, iterFun)
w.Close()
if err != nil {
return nil, err
}
return NewCdbMap(nm)
}
func (m *CdbMap) Get(key Key) (element *NeedleValue, ok bool) {
util.Uint64toBytes(m.transient, uint64(key))
data, err := m.db.Data(m.transient)
if err != nil {
if err == io.EOF {
return nil, false
}
log.Printf("error getting %s: %s", key, err)
return nil, false
}
return &NeedleValue{Key: key,
Offset: util.BytesToUint32(data[:4]),
Size: util.BytesToUint32(data[4:8]),
}, true
}
func (m *CdbMap) Walk(pedestrian func(*NeedleValue) error) (err error) {
r, err := os.Open(m.Filename)
if err != nil {
return err
}
defer r.Close()
iterFunc := func(elt cdb.Element) error {
return pedestrian(&NeedleValue{
Key: Key(util.BytesToUint64(elt.Key[:8])),
Offset: util.BytesToUint32(elt.Data[:4]),
Size: util.BytesToUint32(elt.Data[4:8]),
})
}
return cdb.DumpMap(r, iterFunc)
}

View file

@ -109,8 +109,8 @@ type CompactMap struct {
list []CompactSection
}
func NewCompactMap() *CompactMap {
return &CompactMap{}
func NewCompactMap() CompactMap {
return CompactMap{}
}
func (cm *CompactMap) Set(key Key, offset uint32, size uint32) uint32 {

View file

@ -1,7 +1,6 @@
package storage
import (
"io"
"log"
"os"
"pkg/util"
@ -9,8 +8,7 @@ import (
type NeedleMap struct {
indexFile *os.File
m MapGetSetter // modifiable map
fm MapGetter // frozen map
m CompactMap
//transient
bytes []byte
@ -21,106 +19,52 @@ type NeedleMap struct {
fileByteCounter uint64
}
// Map interface for frozen maps
type MapGetter interface {
Get(key Key) (element *NeedleValue, ok bool)
Walk(pedestrian func(*NeedleValue) error) error
}
// Modifiable map interface
type MapSetter interface {
Set(key Key, offset, size uint32) (oldsize uint32)
Delete(key Key) uint32
}
// Settable and gettable map
type MapGetSetter interface {
MapGetter
MapSetter
}
// New in-memory needle map, backed by "file" index file
func NewNeedleMap(file *os.File) *NeedleMap {
return &NeedleMap{
nm := &NeedleMap{
m: NewCompactMap(),
bytes: make([]byte, 16),
indexFile: file,
}
}
// Nes frozen (on-disk, not modifiable(!)) needle map
func NewFrozenNeedleMap(file *os.File) (*NeedleMap, error) {
fm, err := NewCdbMapFromIndex(file)
if err != nil {
return nil, err
}
return &NeedleMap{
fm: fm,
bytes: make([]byte, 16),
}, nil
return nm
}
const (
RowsToRead = 1024
)
func LoadNeedleMap(file *os.File) (*NeedleMap, error) {
func LoadNeedleMap(file *os.File) *NeedleMap {
nm := NewNeedleMap(file)
var (
key uint64
offset, size, oldSize uint32
)
iterFun := func(buf []byte) error {
key = util.BytesToUint64(buf[:8])
offset = util.BytesToUint32(buf[8:12])
size = util.BytesToUint32(buf[12:16])
nm.fileCounter++
nm.fileByteCounter = nm.fileByteCounter + uint64(size)
if offset > 0 {
oldSize = nm.m.Set(Key(key), offset, size)
//log.Println("reading key", key, "offset", offset, "size", size, "oldSize", oldSize)
if oldSize > 0 {
nm.deletionCounter++
nm.deletionByteCounter = nm.deletionByteCounter + uint64(oldSize)
}
} else {
nm.m.Delete(Key(key))
//log.Println("removing key", key)
nm.deletionCounter++
nm.deletionByteCounter = nm.deletionByteCounter + uint64(size)
}
return nil
}
if err := readIndexFile(file, iterFun); err != nil {
return nil, err
}
return nm, nil
}
// calls iterFun with each row (raw 16 bytes)
func readIndexFile(indexFile *os.File, iterFun func([]byte) error) error {
buf := make([]byte, 16*RowsToRead)
count, e := io.ReadAtLeast(indexFile, buf, 16)
if e != nil && count > 0 {
fstat, err := indexFile.Stat()
if err != nil {
log.Println("ERROR stating %s: %s", indexFile, err)
} else {
log.Println("Loading index file", fstat.Name(), "size", fstat.Size())
}
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 {
if e = iterFun(buf[i : i+16]); e != nil {
return e
key := util.BytesToUint64(bytes[i : i+8])
offset := util.BytesToUint32(bytes[i+8 : i+12])
size := util.BytesToUint32(bytes[i+12 : i+16])
nm.fileCounter++
nm.fileByteCounter = nm.fileByteCounter + uint64(size)
if offset > 0 {
oldSize := nm.m.Set(Key(key), offset, size)
//log.Println("reading key", key, "offset", offset, "size", size, "oldSize", oldSize)
if oldSize > 0 {
nm.deletionCounter++
nm.deletionByteCounter = nm.deletionByteCounter + uint64(oldSize)
}
} else {
nm.m.Delete(Key(key))
//log.Println("removing key", key)
nm.deletionCounter++
nm.deletionByteCounter = nm.deletionByteCounter + uint64(size)
}
}
count, e = io.ReadAtLeast(indexFile, buf, 16)
count, e = nm.indexFile.Read(bytes)
}
return nil
return nm
}
func (nm *NeedleMap) Put(key uint64, offset uint32, size uint32) (int, error) {

View file

@ -48,8 +48,8 @@ func (v *Volume) load() error {
if ie != nil {
return fmt.Errorf("cannot create Volume Data %s.dat: %s", fileName, e)
}
v.nm, e = LoadNeedleMap(indexFile)
return e
v.nm = LoadNeedleMap(indexFile)
return nil
}
func (v *Volume) Version() Version {
return v.version