Golang fileutil.Preallocate函数代码示例

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本文整理汇总了Golang中github.com/coreos/etcd/pkg/fileutil.Preallocate函数的典型用法代码示例。如果您正苦于以下问题：Golang Preallocate函数的具体用法？Golang Preallocate怎么用？Golang Preallocate使用的例子？那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。

在下文中一共展示了Preallocate函数的9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，您的评价将有助于我们的系统推荐出更棒的Golang代码示例。

示例1: Create

// Create creates a WAL ready for appending records. The given metadata is
// recorded at the head of each WAL file, and can be retrieved with ReadAll.
func Create(dirpath string, metadata []byte) (*WAL, error) {
	if Exist(dirpath) {
		return nil, os.ErrExist
	}

	// keep temporary wal directory so WAL initialization appears atomic
	tmpdirpath := path.Clean(dirpath) + ".tmp"
	if fileutil.Exist(tmpdirpath) {
		if err := os.RemoveAll(tmpdirpath); err != nil {
			return nil, err
		}
	}
	if err := os.MkdirAll(tmpdirpath, fileutil.PrivateDirMode); err != nil {
		return nil, err
	}

	p := path.Join(tmpdirpath, walName(0, 0))
	f, err := fileutil.LockFile(p, os.O_WRONLY|os.O_CREATE, fileutil.PrivateFileMode)
	if err != nil {
		return nil, err
	}
	if _, err := f.Seek(0, os.SEEK_END); err != nil {
		return nil, err
	}
	if err := fileutil.Preallocate(f.File, segmentSizeBytes, true); err != nil {
		return nil, err
	}

	w := &WAL{
		dir:      dirpath,
		metadata: metadata,
		encoder:  newEncoder(f, 0),
	}
	w.locks = append(w.locks, f)
	if err := w.saveCrc(0); err != nil {
		return nil, err
	}
	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: metadata}); err != nil {
		return nil, err
	}
	if err := w.SaveSnapshot(walpb.Snapshot{}); err != nil {
		return nil, err
	}

	if err := os.RemoveAll(dirpath); err != nil {
		return nil, err
	}
	if err := os.Rename(tmpdirpath, dirpath); err != nil {
		return nil, err
	}

	w.fp = newFilePipeline(w.dir, segmentSizeBytes)
	return w, nil
}

开发者ID:pulcy，项目名称:j2，代码行数:56，代码来源:wal.go

示例2: alloc

func (fp *filePipeline) alloc() (f *fileutil.LockedFile, err error) {
	fpath := path.Join(fp.dir, fmt.Sprintf("%d.tmp", fp.count))
	if f, err = fileutil.LockFile(fpath, os.O_CREATE|os.O_WRONLY, 0600); err != nil {
		return nil, err
	}
	if err = fileutil.Preallocate(f.File, fp.size, true); err != nil {
		plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
		f.Close()
		return nil, err
	}
	fp.count++
	return f, nil
}

开发者ID:XiangrongFan，项目名称:etcd，代码行数:13，代码来源:file_pipeline.go

示例3: alloc

func (fp *filePipeline) alloc() (f *fileutil.LockedFile, err error) {
	// count % 2 so this file isn't the same as the one last published
	fpath := path.Join(fp.dir, fmt.Sprintf("%d.tmp", fp.count%2))
	if f, err = fileutil.LockFile(fpath, os.O_CREATE|os.O_WRONLY, fileutil.PrivateFileMode); err != nil {
		return nil, err
	}
	if err = fileutil.Preallocate(f.File, fp.size, true); err != nil {
		plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
		f.Close()
		return nil, err
	}
	fp.count++
	return f, nil
}

开发者ID:CliffYuan，项目名称:etcd，代码行数:14，代码来源:file_pipeline.go

示例4: Create

// Create creates a WAL ready for appending records. The given metadata is
// recorded at the head of each WAL file, and can be retrieved with ReadAll.
func Create(dirpath string, metadata []byte) (*WAL, error) {
	if Exist(dirpath) {
		return nil, os.ErrExist
	}

	if err := os.MkdirAll(dirpath, privateDirMode); err != nil {
		return nil, err
	}

	p := path.Join(dirpath, walName(0, 0))
	f, err := fileutil.LockFile(p, os.O_WRONLY|os.O_CREATE, 0600)
	if err != nil {
		return nil, err
	}
	if _, err := f.Seek(0, os.SEEK_END); err != nil {
		return nil, err
	}
	if err := fileutil.Preallocate(f.File, segmentSizeBytes, true); err != nil {
		return nil, err
	}

	w := &WAL{
		dir:      dirpath,
		metadata: metadata,
		encoder:  newEncoder(f, 0),
		fp:       newFilePipeline(dirpath, segmentSizeBytes),
	}
	w.locks = append(w.locks, f)
	if err := w.saveCrc(0); err != nil {
		return nil, err
	}
	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: metadata}); err != nil {
		return nil, err
	}
	if err := w.SaveSnapshot(walpb.Snapshot{}); err != nil {
		return nil, err
	}
	return w, nil
}

开发者ID:oywc410，项目名称:MYPG，代码行数:41，代码来源:wal.go

示例5: Create

// Create creates a WAL ready for appending records. The given metadata is
// recorded at the head of each WAL file, and can be retrieved with ReadAll.
func Create(dirpath string, metadata []byte) (*WAL, error) {
	if Exist(dirpath) {
		return nil, os.ErrExist
	}

	// keep temporary wal directory so WAL initialization appears atomic
	tmpdirpath := path.Clean(dirpath) + ".tmp"
	if fileutil.Exist(tmpdirpath) {
		if err := os.RemoveAll(tmpdirpath); err != nil {
			return nil, err
		}
	}
	if err := fileutil.CreateDirAll(tmpdirpath); err != nil {
		return nil, err
	}

	p := path.Join(tmpdirpath, walName(0, 0))
	f, err := fileutil.LockFile(p, os.O_WRONLY|os.O_CREATE, fileutil.PrivateFileMode)
	if err != nil {
		return nil, err
	}
	if _, err = f.Seek(0, os.SEEK_END); err != nil {
		return nil, err
	}
	if err = fileutil.Preallocate(f.File, SegmentSizeBytes, true); err != nil {
		return nil, err
	}

	w := &WAL{
		dir:      dirpath,
		metadata: metadata,
		encoder:  newEncoder(f, 0),
	}
	w.locks = append(w.locks, f)
	if err = w.saveCrc(0); err != nil {
		return nil, err
	}
	if err = w.encoder.encode(&walpb.Record{Type: metadataType, Data: metadata}); err != nil {
		return nil, err
	}
	if err = w.SaveSnapshot(walpb.Snapshot{}); err != nil {
		return nil, err
	}

	if w, err = w.renameWal(tmpdirpath); err != nil {
		return nil, err
	}

	// directory was renamed; sync parent dir to persist rename
	pdir, perr := fileutil.OpenDir(path.Dir(w.dir))
	if perr != nil {
		return nil, perr
	}
	if perr = fileutil.Fsync(pdir); perr != nil {
		return nil, perr
	}
	if perr = pdir.Close(); err != nil {
		return nil, perr
	}

	return w, nil
}

开发者ID:pweil-，项目名称:origin，代码行数:64，代码来源:wal.go

示例6: Create

// Create creates a WAL ready for appending records. The given metadata is
// recorded at the head of each WAL file, and can be retrieved with ReadAll.
func Create(dirpath string, metadata []byte) (*WAL, error) {
	if Exist(dirpath) {
		return nil, os.ErrExist
	}

	// keep temporary wal directory so WAL initialization appears atomic
	tmpdirpath := path.Clean(dirpath) + ".tmp"
	if fileutil.Exist(tmpdirpath) {
		if err := os.RemoveAll(tmpdirpath); err != nil {
			return nil, err
		}
	}
	if err := fileutil.CreateDirAll(tmpdirpath); err != nil {
		return nil, err
	}

	p := path.Join(tmpdirpath, walName(0, 0))
	f, err := fileutil.LockFile(p, os.O_WRONLY|os.O_CREATE, fileutil.PrivateFileMode)
	if err != nil {
		return nil, err
	}
	if _, err := f.Seek(0, os.SEEK_END); err != nil {
		return nil, err
	}
	if err := fileutil.Preallocate(f.File, SegmentSizeBytes, true); err != nil {
		return nil, err
	}

	w := &WAL{
		dir:      dirpath,
		metadata: metadata,
		encoder:  newEncoder(f, 0),
	}
	w.locks = append(w.locks, f)
	if err := w.saveCrc(0); err != nil {
		return nil, err
	}
	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: metadata}); err != nil {
		return nil, err
	}
	if err := w.SaveSnapshot(walpb.Snapshot{}); err != nil {
		return nil, err
	}

	// rename of directory with locked files doesn't work on windows; close
	// the WAL to release the locks so the directory can be renamed
	w.Close()
	if err := os.Rename(tmpdirpath, dirpath); err != nil {
		return nil, err
	}
	// reopen and relock
	newWAL, oerr := Open(dirpath, walpb.Snapshot{})
	if oerr != nil {
		return nil, oerr
	}
	if _, _, _, err := newWAL.ReadAll(); err != nil {
		newWAL.Close()
		return nil, err
	}
	return newWAL, nil
}

开发者ID:maxim28，项目名称:docker，代码行数:63，代码来源:wal.go

示例7: cut

// cut closes current file written and creates a new one ready to append.
// cut first creates a temp wal file and writes necessary headers into it.
// Then cut atomtically rename temp wal file to a wal file.
func (w *WAL) cut() error {
	// close old wal file
	if err := w.sync(); err != nil {
		return err
	}
	if err := w.f.Close(); err != nil {
		return err
	}

	fpath := path.Join(w.dir, walName(w.seq+1, w.enti+1))
	ftpath := fpath + ".tmp"

	// create a temp wal file with name sequence + 1, or tuncate the existing one
	ft, err := os.OpenFile(ftpath, os.O_WRONLY|os.O_APPEND|os.O_CREATE|os.O_TRUNC, 0600)
	if err != nil {
		return err
	}

	// update writer and save the previous crc
	w.f = ft
	prevCrc := w.encoder.crc.Sum32()
	w.encoder = newEncoder(w.f, prevCrc)
	if err := w.saveCrc(prevCrc); err != nil {
		return err
	}
	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: w.metadata}); err != nil {
		return err
	}
	if err := w.saveState(&w.state); err != nil {
		return err
	}
	// close temp wal file
	if err := w.sync(); err != nil {
		return err
	}
	if err := w.f.Close(); err != nil {
		return err
	}

	// atomically move temp wal file to wal file
	if err := os.Rename(ftpath, fpath); err != nil {
		return err
	}

	// open the wal file and update writer again
	f, err := os.OpenFile(fpath, os.O_WRONLY|os.O_APPEND, 0600)
	if err != nil {
		return err
	}
	err = fileutil.Preallocate(f, segmentSizeBytes)
	if err != nil {
		plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
		return err
	}

	w.f = f
	prevCrc = w.encoder.crc.Sum32()
	w.encoder = newEncoder(w.f, prevCrc)

	// lock the new wal file
	l, err := fileutil.NewLock(f.Name())
	if err != nil {
		return err
	}

	err = l.Lock()
	if err != nil {
		return err
	}
	w.locks = append(w.locks, l)

	// increase the wal seq
	w.seq++

	plog.Infof("segmented wal file %v is created", fpath)
	return nil
}

开发者ID:rnd-ua，项目名称:scope，代码行数:80，代码来源:wal.go

示例8: openAtIndex

func openAtIndex(dirpath string, snap walpb.Snapshot, write bool) (*WAL, error) {
	names, err := fileutil.ReadDir(dirpath)
	if err != nil {
		return nil, err
	}
	names = checkWalNames(names)
	if len(names) == 0 {
		return nil, ErrFileNotFound
	}

	nameIndex, ok := searchIndex(names, snap.Index)
	if !ok || !isValidSeq(names[nameIndex:]) {
		return nil, ErrFileNotFound
	}

	// open the wal files for reading
	rcs := make([]io.ReadCloser, 0)
	ls := make([]fileutil.Lock, 0)
	for _, name := range names[nameIndex:] {
		f, err := os.Open(path.Join(dirpath, name))
		if err != nil {
			return nil, err
		}
		l, err := fileutil.NewLock(f.Name())
		if err != nil {
			return nil, err
		}
		err = l.TryLock()
		if err != nil {
			if write {
				return nil, err
			}
		}
		rcs = append(rcs, f)
		ls = append(ls, l)
	}
	rc := MultiReadCloser(rcs...)

	// create a WAL ready for reading
	w := &WAL{
		dir:     dirpath,
		start:   snap,
		decoder: newDecoder(rc),
		locks:   ls,
	}

	if write {
		// open the lastest wal file for appending
		seq, _, err := parseWalName(names[len(names)-1])
		if err != nil {
			rc.Close()
			return nil, err
		}
		last := path.Join(dirpath, names[len(names)-1])

		f, err := os.OpenFile(last, os.O_WRONLY|os.O_APPEND, 0)
		if err != nil {
			rc.Close()
			return nil, err
		}
		err = fileutil.Preallocate(f, segmentSizeBytes)
		if err != nil {
			rc.Close()
			plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
			return nil, err
		}

		w.f = f
		w.seq = seq
	}

	return w, nil
}

开发者ID:rnd-ua，项目名称:scope，代码行数:73，代码来源:wal.go

示例9: openAtIndex

func openAtIndex(dirpath string, snap walpb.Snapshot, write bool) (*WAL, error) {
	names, err := fileutil.ReadDir(dirpath)
	if err != nil {
		return nil, err
	}
	names = checkWalNames(names)
	if len(names) == 0 {
		return nil, ErrFileNotFound
	}

	nameIndex, ok := searchIndex(names, snap.Index)
	if !ok || !isValidSeq(names[nameIndex:]) {
		return nil, ErrFileNotFound
	}

	// open the wal files
	rcs := make([]io.ReadCloser, 0)
	rs := make([]io.Reader, 0)
	ls := make([]*fileutil.LockedFile, 0)
	for _, name := range names[nameIndex:] {
		p := path.Join(dirpath, name)
		if write {
			l, err := fileutil.TryLockFile(p, os.O_RDWR, 0600)
			if err != nil {
				closeAll(rcs...)
				return nil, err
			}
			ls = append(ls, l)
			rcs = append(rcs, l)
		} else {
			rf, err := os.OpenFile(p, os.O_RDONLY, 0600)
			if err != nil {
				closeAll(rcs...)
				return nil, err
			}
			ls = append(ls, nil)
			rcs = append(rcs, rf)
		}
		rs = append(rs, rcs[len(rcs)-1])
	}

	closer := func() error { return closeAll(rcs...) }

	// create a WAL ready for reading
	w := &WAL{
		dir:       dirpath,
		start:     snap,
		decoder:   newDecoder(rs...),
		readClose: closer,
		locks:     ls,
	}

	if write {
		// write reuses the file descriptors from read; don't close so
		// WAL can append without dropping the file lock
		w.readClose = nil

		if _, _, err := parseWalName(path.Base(w.tail().Name())); err != nil {
			closer()
			return nil, err
		}
		// don't resize file for preallocation in case tail is corrupted
		if err := fileutil.Preallocate(w.tail().File, segmentSizeBytes, false); err != nil {
			closer()
			plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
			return nil, err
		}
		w.fp = newFilePipeline(w.dir, segmentSizeBytes)
	}

	return w, nil
}

开发者ID:oywc410，项目名称:MYPG，代码行数:72，代码来源:wal.go

注：本文中的github.com/coreos/etcd/pkg/fileutil.Preallocate函数示例整理自Github/MSDocs等源码及文档管理平台，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。