func (db *DB) recoverJournal() error {
// Get all journals and sort it by file number.
allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
if err != nil {
return err
}
files(allJournalFiles).sort()
// Journals that will be recovered.
var recJournalFiles []storage.File
for _, jf := range allJournalFiles {
if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
recJournalFiles = append(recJournalFiles, jf)
}
}
var (
of storage.File // Obsolete file.
rec = &sessionRecord{}
)
// Recover journals.
if len(recJournalFiles) > 0 {
db.logf("journal@recovery F·%d", len(recJournalFiles))
// Mark file number as used.
db.s.markFileNum(recJournalFiles[len(recJournalFiles)-1].Num())
var (
// Options.
strict = db.s.o.GetStrict(opt.StrictJournal)
checksum = db.s.o.GetStrict(opt.StrictJournalChecksum)
writeBuffer = db.s.o.GetWriteBuffer()
jr *journal.Reader
mdb = memdb.New(db.s.icmp, writeBuffer)
buf = &util.Buffer{}
batch = &Batch{}
)
for _, jf := range recJournalFiles {
db.logf("journal@recovery recovering @%d", jf.Num())
fr, err := jf.Open()
if err != nil {
return err
}
// Create or reset journal reader instance.
if jr == nil {
jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
} else {
jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
}
// Flush memdb and remove obsolete journal file.
if of != nil {
if mdb.Len() > 0 {
if _, err := db.s.flushMemdb(rec, mdb, -1); err != nil {
fr.Close()
return err
}
}
rec.setJournalNum(jf.Num())
rec.setSeqNum(db.seq)
if err := db.s.commit(rec); err != nil {
fr.Close()
return err
}
rec.resetAddedTables()
of.Remove()
of = nil
}
// Replay journal to memdb.
mdb.Reset()
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
fr.Close()
return errors.SetFile(err, jf)
}
buf.Reset()
if _, err := buf.ReadFrom(r); err != nil {
if err == io.ErrUnexpectedEOF {
// This is error returned due to corruption, with strict == false.
continue
}
fr.Close()
return errors.SetFile(err, jf)
}
if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
if !strict && errors.IsCorrupted(err) {
db.s.logf("journal error: %v (skipped)", err)
// We won't apply sequence number as it might be corrupted.
continue
}
fr.Close()
return errors.SetFile(err, jf)
}
// Save sequence number.
db.seq = batch.seq + uint64(batch.Len())
// Flush it if large enough.
if mdb.Size() >= writeBuffer {
if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
fr.Close()
return err
}
mdb.Reset()
}
}
fr.Close()
of = jf
}
// Flush the last memdb.
if mdb.Len() > 0 {
if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
return err
}
}
}
// Create a new journal.
if _, err := db.newMem(0); err != nil {
return err
}
// Commit.
rec.setJournalNum(db.journalFile.Num())
rec.setSeqNum(db.seq)
if err := db.s.commit(rec); err != nil {
// Close journal on error.
if db.journal != nil {
db.journal.Close()
db.journalWriter.Close()
}
return err
}
// Remove the last obsolete journal file.
if of != nil {
of.Remove()
}
return nil
}
func (db *DB) recoverJournalRO() error {
// Get all journals and sort it by file number.
allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
if err != nil {
return err
}
files(allJournalFiles).sort()
// Journals that will be recovered.
var recJournalFiles []storage.File
for _, jf := range allJournalFiles {
if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
recJournalFiles = append(recJournalFiles, jf)
}
}
var (
// Options.
strict = db.s.o.GetStrict(opt.StrictJournal)
checksum = db.s.o.GetStrict(opt.StrictJournalChecksum)
writeBuffer = db.s.o.GetWriteBuffer()
mdb = memdb.New(db.s.icmp, writeBuffer)
)
// Recover journals.
if len(recJournalFiles) > 0 {
db.logf("journal@recovery RO·Mode F·%d", len(recJournalFiles))
var (
jr *journal.Reader
buf = &util.Buffer{}
batch = &Batch{}
)
for _, jf := range recJournalFiles {
db.logf("journal@recovery recovering @%d", jf.Num())
fr, err := jf.Open()
if err != nil {
return err
}
// Create or reset journal reader instance.
if jr == nil {
jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
} else {
jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
}
// Replay journal to memdb.
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
fr.Close()
return errors.SetFile(err, jf)
}
buf.Reset()
if _, err := buf.ReadFrom(r); err != nil {
if err == io.ErrUnexpectedEOF {
// This is error returned due to corruption, with strict == false.
continue
}
fr.Close()
return errors.SetFile(err, jf)
}
if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
if !strict && errors.IsCorrupted(err) {
db.s.logf("journal error: %v (skipped)", err)
// We won't apply sequence number as it might be corrupted.
continue
}
fr.Close()
return errors.SetFile(err, jf)
}
// Save sequence number.
db.seq = batch.seq + uint64(batch.Len())
}
fr.Close()
}
}
// Set memDB.
db.mem = &memDB{db: db, DB: mdb, ref: 1}
return nil
}
// Recover a database session; need external synchronization.
func (s *session) recover() (err error) {
defer func() {
if os.IsNotExist(err) {
// Don't return os.ErrNotExist if the underlying storage contains
// other files that belong to LevelDB. So the DB won't get trashed.
if files, _ := s.stor.GetFiles(storage.TypeAll); len(files) > 0 {
err = &errors.ErrCorrupted{File: &storage.FileInfo{Type: storage.TypeManifest}, Err: &errors.ErrMissingFiles{}}
}
}
}()
m, err := s.stor.GetManifest()
if err != nil {
return
}
reader, err := m.Open()
if err != nil {
return
}
defer reader.Close()
var (
// Options.
numLevel = s.o.GetNumLevel()
strict = s.o.GetStrict(opt.StrictManifest)
jr = journal.NewReader(reader, dropper{s, m}, strict, true)
rec = &sessionRecord{}
staging = s.stVersion.newStaging()
)
for {
var r io.Reader
r, err = jr.Next()
if err != nil {
if err == io.EOF {
err = nil
break
}
return errors.SetFile(err, m)
}
err = rec.decode(r, numLevel)
if err == nil {
// save compact pointers
for _, r := range rec.compPtrs {
s.stCompPtrs[r.level] = iKey(r.ikey)
}
// commit record to version staging
staging.commit(rec)
} else {
err = errors.SetFile(err, m)
if strict || !errors.IsCorrupted(err) {
return
} else {
s.logf("manifest error: %v (skipped)", errors.SetFile(err, m))
}
}
rec.resetCompPtrs()
rec.resetAddedTables()
rec.resetDeletedTables()
}
switch {
case !rec.has(recComparer):
return newErrManifestCorrupted(m, "comparer", "missing")
case rec.comparer != s.icmp.uName():
return newErrManifestCorrupted(m, "comparer", fmt.Sprintf("mismatch: want '%s', got '%s'", s.icmp.uName(), rec.comparer))
case !rec.has(recNextFileNum):
return newErrManifestCorrupted(m, "next-file-num", "missing")
case !rec.has(recJournalNum):
return newErrManifestCorrupted(m, "journal-file-num", "missing")
case !rec.has(recSeqNum):
return newErrManifestCorrupted(m, "seq-num", "missing")
}
s.manifestFile = m
s.setVersion(staging.finish())
s.setNextFileNum(rec.nextFileNum)
s.recordCommited(rec)
return nil
}