// Opens table. It returns a cache handle, which should
// be released after use.
func (t *tOps) open(f *tFile) (ch cache.Handle, err error) {
num := f.file.Num()
ch = t.cacheNS.Get(num, func() (charge int, value interface{}) {
var r storage.Reader
r, err = f.file.Open()
if err != nil {
return 0, nil
}
var bcacheNS cache.Namespace
if bc := t.s.o.GetBlockCache(); bc != nil {
bcacheNS = bc.GetNamespace(num)
}
var tr *table.Reader
tr, err = table.NewReader(r, int64(f.size), storage.NewFileInfo(f.file), bcacheNS, t.bpool, t.s.o.Options)
if err != nil {
r.Close()
return 0, nil
}
return 1, tr
})
if ch == nil && err == nil {
err = ErrClosed
}
return
}
func recoverTable(s *session, o *opt.Options) error {
o = dupOptions(o)
// Mask StrictReader, lets StrictRecovery doing its job.
o.Strict &= ^opt.StrictReader
// Get all tables and sort it by file number.
tableFiles_, err := s.getFiles(storage.TypeTable)
if err != nil {
return err
}
tableFiles := files(tableFiles_)
tableFiles.sort()
var (
maxSeq uint64
recoveredKey, goodKey, corruptedKey, corruptedBlock, droppedTable int
// We will drop corrupted table.
strict = o.GetStrict(opt.StrictRecovery)
rec = &sessionRecord{numLevel: o.GetNumLevel()}
bpool = util.NewBufferPool(o.GetBlockSize() + 5)
)
buildTable := func(iter iterator.Iterator) (tmp storage.File, size int64, err error) {
tmp = s.newTemp()
writer, err := tmp.Create()
if err != nil {
return
}
defer func() {
writer.Close()
if err != nil {
tmp.Remove()
tmp = nil
}
}()
// Copy entries.
tw := table.NewWriter(writer, o)
for iter.Next() {
key := iter.Key()
if validIkey(key) {
err = tw.Append(key, iter.Value())
if err != nil {
return
}
}
}
err = iter.Error()
if err != nil {
return
}
err = tw.Close()
if err != nil {
return
}
err = writer.Sync()
if err != nil {
return
}
size = int64(tw.BytesLen())
return
}
recoverTable := func(file storage.File) error {
s.logf("table@recovery recovering @%d", file.Num())
reader, err := file.Open()
if err != nil {
return err
}
var closed bool
defer func() {
if !closed {
reader.Close()
}
}()
// Get file size.
size, err := reader.Seek(0, 2)
if err != nil {
return err
}
var (
tSeq uint64
tgoodKey, tcorruptedKey, tcorruptedBlock int
imin, imax []byte
)
tr, err := table.NewReader(reader, size, storage.NewFileInfo(file), nil, bpool, o)
if err != nil {
return err
}
iter := tr.NewIterator(nil, nil)
iter.(iterator.ErrorCallbackSetter).SetErrorCallback(func(err error) {
if errors.IsCorrupted(err) {
s.logf("table@recovery block corruption @%d %q", file.Num(), err)
tcorruptedBlock++
}
})
// Scan the table.
for iter.Next() {
key := iter.Key()
_, seq, _, kerr := parseIkey(key)
if kerr != nil {
tcorruptedKey++
continue
}
tgoodKey++
if seq > tSeq {
tSeq = seq
}
if imin == nil {
imin = append([]byte{}, key...)
}
imax = append(imax[:0], key...)
}
if err := iter.Error(); err != nil {
iter.Release()
return err
}
iter.Release()
goodKey += tgoodKey
corruptedKey += tcorruptedKey
corruptedBlock += tcorruptedBlock
if strict && (tcorruptedKey > 0 || tcorruptedBlock > 0) {
droppedTable++
s.logf("table@recovery dropped @%d Gk·%d Ck·%d Cb·%d S·%d Q·%d", file.Num(), tgoodKey, tcorruptedKey, tcorruptedBlock, size, tSeq)
return nil
}
if tgoodKey > 0 {
if tcorruptedKey > 0 || tcorruptedBlock > 0 {
// Rebuild the table.
s.logf("table@recovery rebuilding @%d", file.Num())
iter := tr.NewIterator(nil, nil)
tmp, newSize, err := buildTable(iter)
iter.Release()
if err != nil {
return err
}
closed = true
reader.Close()
if err := file.Replace(tmp); err != nil {
return err
}
size = newSize
}
if tSeq > maxSeq {
maxSeq = tSeq
}
recoveredKey += tgoodKey
// Add table to level 0.
rec.addTable(0, file.Num(), uint64(size), imin, imax)
s.logf("table@recovery recovered @%d Gk·%d Ck·%d Cb·%d S·%d Q·%d", file.Num(), tgoodKey, tcorruptedKey, tcorruptedBlock, size, tSeq)
} else {
droppedTable++
s.logf("table@recovery unrecoverable @%d Ck·%d Cb·%d S·%d", file.Num(), tcorruptedKey, tcorruptedBlock, size)
}
return nil
}
// Recover all tables.
if len(tableFiles) > 0 {
s.logf("table@recovery F·%d", len(tableFiles))
// Mark file number as used.
s.markFileNum(tableFiles[len(tableFiles)-1].Num())
for _, file := range tableFiles {
if err := recoverTable(file); err != nil {
return err
}
}
s.logf("table@recovery recovered F·%d N·%d Gk·%d Ck·%d Q·%d", len(tableFiles), recoveredKey, goodKey, corruptedKey, maxSeq)
}
// Set sequence number.
rec.setSeqNum(maxSeq)
// Create new manifest.
if err := s.create(); err != nil {
return err
}
// Commit.
return s.commit(rec)
}