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Golang journal.Reader类代码示例

本文整理汇总了Golang中github.com/syndtr/goleveldb/leveldb/journal.Reader的典型用法代码示例。如果您正苦于以下问题:Golang Reader类的具体用法?Golang Reader怎么用?Golang Reader使用的例子?那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。


在下文中一共展示了Reader类的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.........
开发者ID:Blueprint-Marketing,项目名称:syncthing,代码行数:101,代码来源:db.go

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.........
开发者ID:KosyanMedia,项目名称:burlesque,代码行数:101,代码来源:db.go

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
}
开发者ID:KosyanMedia,项目名称:burlesque,代码行数:96,代码来源:db.go

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.........
开发者ID:ZSIT,项目名称:syncthing,代码行数:101,代码来源:db.go


注:本文中的github.com/syndtr/goleveldb/leveldb/journal.Reader类示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。