本文整理汇总了Golang中github.com/syndtr/goleveldb/leveldb/journal.Reader.Next方法的典型用法代码示例。如果您正苦于以下问题：Golang Reader.Next方法的具体用法？Golang Reader.Next怎么用？Golang Reader.Next使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类github.com/syndtr/goleveldb/leveldb/journal.Reader的用法示例。
在下文中一共展示了Reader.Next方法的4个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Golang代码示例。
示例1: recoverJournal
func (db *DB) recoverJournal() error {
// Get all tables and sort it by file number.
journalFiles_, err := db.s.getFiles(storage.TypeJournal)
if err != nil {
return err
}
journalFiles := files(journalFiles_)
journalFiles.sort()
// Discard older journal.
prev := -1
for i, file := range journalFiles {
if file.Num() >= db.s.stJournalNum {
if prev >= 0 {
i--
journalFiles[i] = journalFiles[prev]
}
journalFiles = journalFiles[i:]
break
} else if file.Num() == db.s.stPrevJournalNum {
prev = i
}
}
var jr *journal.Reader
var of storage.File
var mem *memdb.DB
batch := new(Batch)
cm := newCMem(db.s)
buf := new(util.Buffer)
// Options.
strict := db.s.o.GetStrict(opt.StrictJournal)
checksum := db.s.o.GetStrict(opt.StrictJournalChecksum)
writeBuffer := db.s.o.GetWriteBuffer()
recoverJournal := func(file storage.File) error {
db.logf("[email protected] recovering @%d", file.Num())
reader, err := file.Open()
if err != nil {
return err
}
defer reader.Close()
// Create/reset journal reader instance.
if jr == nil {
jr = journal.NewReader(reader, dropper{db.s, file}, strict, checksum)
} else {
jr.Reset(reader, dropper{db.s, file}, strict, checksum)
}
// Flush memdb and remove obsolete journal file.
if of != nil {
if mem.Len() > 0 {
if err := cm.flush(mem, 0); err != nil {
return err
}
}
if err := cm.commit(file.Num(), db.seq); err != nil {
return err
}
cm.reset()
of.Remove()
of = nil
}
// Replay journal to memdb.
mem.Reset()
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
return err
}
buf.Reset()
if _, err := buf.ReadFrom(r); err != nil {
if err == io.ErrUnexpectedEOF {
continue
} else {
return err
}
}
if err := batch.decode(buf.Bytes()); err != nil {
return err
}
if err := batch.memReplay(mem); err != nil {
return err
}
// Save sequence number.
db.seq = batch.seq + uint64(batch.len())
// Flush it if large enough.
if mem.Size() >= writeBuffer {
if err := cm.flush(mem, 0); err != nil {
return err
}
mem.Reset()
}
//.........这里部分代码省略.........
示例2: recoverJournal
func (db *DB) recoverJournal() error {
// Get all journals and sort it by file number.
rawFds, err := db.s.stor.List(storage.TypeJournal)
if err != nil {
return err
}
sortFds(rawFds)
// Journals that will be recovered.
var fds []storage.FileDesc
for _, fd := range rawFds {
if fd.Num >= db.s.stJournalNum || fd.Num == db.s.stPrevJournalNum {
fds = append(fds, fd)
}
}
var (
ofd storage.FileDesc // Obsolete file.
rec = &sessionRecord{}
)
// Recover journals.
if len(fds) > 0 {
db.logf("[email protected] F·%d", len(fds))
// Mark file number as used.
db.s.markFileNum(fds[len(fds)-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 _, fd := range fds {
db.logf("[email protected] recovering @%d", fd.Num)
fr, err := db.s.stor.Open(fd)
if err != nil {
return err
}
// Create or reset journal reader instance.
if jr == nil {
jr = journal.NewReader(fr, dropper{db.s, fd}, strict, checksum)
} else {
jr.Reset(fr, dropper{db.s, fd}, strict, checksum)
}
// Flush memdb and remove obsolete journal file.
if !ofd.Nil() {
if mdb.Len() > 0 {
if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
fr.Close()
return err
}
}
rec.setJournalNum(fd.Num)
rec.setSeqNum(db.seq)
if err := db.s.commit(rec); err != nil {
fr.Close()
return err
}
rec.resetAddedTables()
db.s.stor.Remove(ofd)
ofd = storage.FileDesc{}
}
// Replay journal to memdb.
mdb.Reset()
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
fr.Close()
return errors.SetFd(err, fd)
}
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.SetFd(err, fd)
}
if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
//.........这里部分代码省略.........
示例3: recoverJournalRO
func (db *DB) recoverJournalRO() error {
// Get all journals and sort it by file number.
rawFds, err := db.s.stor.List(storage.TypeJournal)
if err != nil {
return err
}
sortFds(rawFds)
// Journals that will be recovered.
var fds []storage.FileDesc
for _, fd := range rawFds {
if fd.Num >= db.s.stJournalNum || fd.Num == db.s.stPrevJournalNum {
fds = append(fds, fd)
}
}
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(fds) > 0 {
db.logf("[email protected] RO·Mode F·%d", len(fds))
var (
jr *journal.Reader
buf = &util.Buffer{}
batch = &Batch{}
)
for _, fd := range fds {
db.logf("[email protected] recovering @%d", fd.Num)
fr, err := db.s.stor.Open(fd)
if err != nil {
return err
}
// Create or reset journal reader instance.
if jr == nil {
jr = journal.NewReader(fr, dropper{db.s, fd}, strict, checksum)
} else {
jr.Reset(fr, dropper{db.s, fd}, strict, checksum)
}
// Replay journal to memdb.
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
fr.Close()
return errors.SetFd(err, fd)
}
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.SetFd(err, fd)
}
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.SetFd(err, fd)
}
// 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
}示例4: recoverJournal
func (d *DB) recoverJournal() error {
s := d.s
ff0, err := s.getFiles(storage.TypeJournal)
if err != nil {
return err
}
ff1 := files(ff0)
ff1.sort()
ff2 := make([]storage.File, 0, len(ff1))
for _, file := range ff1 {
if file.Num() >= s.stJournalNum || file.Num() == s.stPrevJournalNum {
s.markFileNum(file.Num())
ff2 = append(ff2, file)
}
}
var jr *journal.Reader
var of storage.File
var mem *memdb.DB
batch := new(Batch)
cm := newCMem(s)
buf := new(util.Buffer)
// Options.
strict := s.o.GetStrict(opt.StrictJournal)
checksum := s.o.GetStrict(opt.StrictJournalChecksum)
writeBuffer := s.o.GetWriteBuffer()
recoverJournal := func(file storage.File) error {
s.logf("[email protected] recovering @%d", file.Num())
reader, err := file.Open()
if err != nil {
return err
}
defer reader.Close()
if jr == nil {
jr = journal.NewReader(reader, dropper{s, file}, strict, checksum)
} else {
jr.Reset(reader, dropper{s, file}, strict, checksum)
}
if of != nil {
if mem.Len() > 0 {
if err := cm.flush(mem, 0); err != nil {
return err
}
}
if err := cm.commit(file.Num(), d.seq); err != nil {
return err
}
cm.reset()
of.Remove()
of = nil
}
// Reset memdb.
mem.Reset()
for {
r, err := jr.Next()
if err != nil {
if err == io.EOF {
break
}
return err
}
buf.Reset()
if _, err := buf.ReadFrom(r); err != nil {
if strict {
return err
}
continue
}
if err := batch.decode(buf.Bytes()); err != nil {
return err
}
if err := batch.memReplay(mem); err != nil {
return err
}
d.seq = batch.seq + uint64(batch.len())
if mem.Size() >= writeBuffer {
// Large enough, flush it.
if err := cm.flush(mem, 0); err != nil {
return err
}
// Reset memdb.
mem.Reset()
}
}
of = file
return nil
}
// Recover all journals.
if len(ff2) > 0 {
s.logf("[email protected] F·%d", len(ff2))
mem = memdb.New(s.icmp, writeBuffer)
for _, file := range ff2 {
if err := recoverJournal(file); err != nil {
return err
}
}
// Flush the last journal.
if mem.Len() > 0 {
if err := cm.flush(mem, 0); err != nil {
//.........这里部分代码省略.........