update mod

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage.go

@@ -0,0 +1,671 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reservefs.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package storage
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+var (
+	errFileOpen = errors.New("leveldb/storage: file still open")
+	errReadOnly = errors.New("leveldb/storage: storage is read-only")
+)
+
+type fileLock interface {
+	release() error
+}
+
+type fileStorageLock struct {
+	fs *fileStorage
+}
+
+func (lock *fileStorageLock) Unlock() {
+	if lock.fs != nil {
+		lock.fs.mu.Lock()
+		defer lock.fs.mu.Unlock()
+		if lock.fs.slock == lock {
+			lock.fs.slock = nil
+		}
+	}
+}
+
+type int64Slice []int64
+
+func (p int64Slice) Len() int           { return len(p) }
+func (p int64Slice) Less(i, j int) bool { return p[i] < p[j] }
+func (p int64Slice) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+
+func writeFileSynced(filename string, data []byte, perm os.FileMode) error {
+	f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	n, err := f.Write(data)
+	if err == nil && n < len(data) {
+		err = io.ErrShortWrite
+	}
+	if err1 := f.Sync(); err == nil {
+		err = err1
+	}
+	if err1 := f.Close(); err == nil {
+		err = err1
+	}
+	return err
+}
+
+const logSizeThreshold = 1024 * 1024 // 1 MiB
+
+// fileStorage is a file-system backed storage.
+type fileStorage struct {
+	path     string
+	readOnly bool
+
+	mu      sync.Mutex
+	flock   fileLock
+	slock   *fileStorageLock
+	logw    *os.File
+	logSize int64
+	buf     []byte
+	// Opened file counter; if open < 0 means closed.
+	open int
+	day  int
+}
+
+// OpenFile returns a new filesystem-backed storage implementation with the given
+// path. This also acquire a file lock, so any subsequent attempt to open the
+// same path will fail.
+//
+// The storage must be closed after use, by calling Close method.
+func OpenFile(path string, readOnly bool) (Storage, error) {
+	if fi, err := os.Stat(path); err == nil {
+		if !fi.IsDir() {
+			return nil, fmt.Errorf("leveldb/storage: open %s: not a directory", path)
+		}
+	} else if os.IsNotExist(err) && !readOnly {
+		if err := os.MkdirAll(path, 0755); err != nil {
+			return nil, err
+		}
+	} else {
+		return nil, err
+	}
+
+	flock, err := newFileLock(filepath.Join(path, "LOCK"), readOnly)
+	if err != nil {
+		return nil, err
+	}
+
+	defer func() {
+		if err != nil {
+			flock.release()
+		}
+	}()
+
+	var (
+		logw    *os.File
+		logSize int64
+	)
+	if !readOnly {
+		logw, err = os.OpenFile(filepath.Join(path, "LOG"), os.O_WRONLY|os.O_CREATE, 0644)
+		if err != nil {
+			return nil, err
+		}
+		logSize, err = logw.Seek(0, os.SEEK_END)
+		if err != nil {
+			logw.Close()
+			return nil, err
+		}
+	}
+
+	fs := &fileStorage{
+		path:     path,
+		readOnly: readOnly,
+		flock:    flock,
+		logw:     logw,
+		logSize:  logSize,
+	}
+	runtime.SetFinalizer(fs, (*fileStorage).Close)
+	return fs, nil
+}
+
+func (fs *fileStorage) Lock() (Locker, error) {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return nil, ErrClosed
+	}
+	if fs.readOnly {
+		return &fileStorageLock{}, nil
+	}
+	if fs.slock != nil {
+		return nil, ErrLocked
+	}
+	fs.slock = &fileStorageLock{fs: fs}
+	return fs.slock, nil
+}
+
+func itoa(buf []byte, i int, wid int) []byte {
+	u := uint(i)
+	if u == 0 && wid <= 1 {
+		return append(buf, '0')
+	}
+
+	// Assemble decimal in reverse order.
+	var b [32]byte
+	bp := len(b)
+	for ; u > 0 || wid > 0; u /= 10 {
+		bp--
+		wid--
+		b[bp] = byte(u%10) + '0'
+	}
+	return append(buf, b[bp:]...)
+}
+
+func (fs *fileStorage) printDay(t time.Time) {
+	if fs.day == t.Day() {
+		return
+	}
+	fs.day = t.Day()
+	fs.logw.Write([]byte("=============== " + t.Format("Jan 2, 2006 (MST)") + " ===============\n"))
+}
+
+func (fs *fileStorage) doLog(t time.Time, str string) {
+	if fs.logSize > logSizeThreshold {
+		// Rotate log file.
+		fs.logw.Close()
+		fs.logw = nil
+		fs.logSize = 0
+		rename(filepath.Join(fs.path, "LOG"), filepath.Join(fs.path, "LOG.old"))
+	}
+	if fs.logw == nil {
+		var err error
+		fs.logw, err = os.OpenFile(filepath.Join(fs.path, "LOG"), os.O_WRONLY|os.O_CREATE, 0644)
+		if err != nil {
+			return
+		}
+		// Force printDay on new log file.
+		fs.day = 0
+	}
+	fs.printDay(t)
+	hour, min, sec := t.Clock()
+	msec := t.Nanosecond() / 1e3
+	// time
+	fs.buf = itoa(fs.buf[:0], hour, 2)
+	fs.buf = append(fs.buf, ':')
+	fs.buf = itoa(fs.buf, min, 2)
+	fs.buf = append(fs.buf, ':')
+	fs.buf = itoa(fs.buf, sec, 2)
+	fs.buf = append(fs.buf, '.')
+	fs.buf = itoa(fs.buf, msec, 6)
+	fs.buf = append(fs.buf, ' ')
+	// write
+	fs.buf = append(fs.buf, []byte(str)...)
+	fs.buf = append(fs.buf, '\n')
+	n, _ := fs.logw.Write(fs.buf)
+	fs.logSize += int64(n)
+}
+
+func (fs *fileStorage) Log(str string) {
+	if !fs.readOnly {
+		t := time.Now()
+		fs.mu.Lock()
+		defer fs.mu.Unlock()
+		if fs.open < 0 {
+			return
+		}
+		fs.doLog(t, str)
+	}
+}
+
+func (fs *fileStorage) log(str string) {
+	if !fs.readOnly {
+		fs.doLog(time.Now(), str)
+	}
+}
+
+func (fs *fileStorage) setMeta(fd FileDesc) error {
+	content := fsGenName(fd) + "\n"
+	// Check and backup old CURRENT file.
+	currentPath := filepath.Join(fs.path, "CURRENT")
+	if _, err := os.Stat(currentPath); err == nil {
+		b, err := ioutil.ReadFile(currentPath)
+		if err != nil {
+			fs.log(fmt.Sprintf("backup CURRENT: %v", err))
+			return err
+		}
+		if string(b) == content {
+			// Content not changed, do nothing.
+			return nil
+		}
+		if err := writeFileSynced(currentPath+".bak", b, 0644); err != nil {
+			fs.log(fmt.Sprintf("backup CURRENT: %v", err))
+			return err
+		}
+	} else if !os.IsNotExist(err) {
+		return err
+	}
+	path := fmt.Sprintf("%s.%d", filepath.Join(fs.path, "CURRENT"), fd.Num)
+	if err := writeFileSynced(path, []byte(content), 0644); err != nil {
+		fs.log(fmt.Sprintf("create CURRENT.%d: %v", fd.Num, err))
+		return err
+	}
+	// Replace CURRENT file.
+	if err := rename(path, currentPath); err != nil {
+		fs.log(fmt.Sprintf("rename CURRENT.%d: %v", fd.Num, err))
+		return err
+	}
+	// Sync root directory.
+	if err := syncDir(fs.path); err != nil {
+		fs.log(fmt.Sprintf("syncDir: %v", err))
+		return err
+	}
+	return nil
+}
+
+func (fs *fileStorage) SetMeta(fd FileDesc) error {
+	if !FileDescOk(fd) {
+		return ErrInvalidFile
+	}
+	if fs.readOnly {
+		return errReadOnly
+	}
+
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return ErrClosed
+	}
+	return fs.setMeta(fd)
+}
+
+func (fs *fileStorage) GetMeta() (FileDesc, error) {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return FileDesc{}, ErrClosed
+	}
+	dir, err := os.Open(fs.path)
+	if err != nil {
+		return FileDesc{}, err
+	}
+	names, err := dir.Readdirnames(0)
+	// Close the dir first before checking for Readdirnames error.
+	if ce := dir.Close(); ce != nil {
+		fs.log(fmt.Sprintf("close dir: %v", ce))
+	}
+	if err != nil {
+		return FileDesc{}, err
+	}
+	// Try this in order:
+	// - CURRENT.[0-9]+ ('pending rename' file, descending order)
+	// - CURRENT
+	// - CURRENT.bak
+	//
+	// Skip corrupted file or file that point to a missing target file.
+	type currentFile struct {
+		name string
+		fd   FileDesc
+	}
+	tryCurrent := func(name string) (*currentFile, error) {
+		b, err := ioutil.ReadFile(filepath.Join(fs.path, name))
+		if err != nil {
+			if os.IsNotExist(err) {
+				err = os.ErrNotExist
+			}
+			return nil, err
+		}
+		var fd FileDesc
+		if len(b) < 1 || b[len(b)-1] != '\n' || !fsParseNamePtr(string(b[:len(b)-1]), &fd) {
+			fs.log(fmt.Sprintf("%s: corrupted content: %q", name, b))
+			err := &ErrCorrupted{
+				Err: errors.New("leveldb/storage: corrupted or incomplete CURRENT file"),
+			}
+			return nil, err
+		}
+		if _, err := os.Stat(filepath.Join(fs.path, fsGenName(fd))); err != nil {
+			if os.IsNotExist(err) {
+				fs.log(fmt.Sprintf("%s: missing target file: %s", name, fd))
+				err = os.ErrNotExist
+			}
+			return nil, err
+		}
+		return &currentFile{name: name, fd: fd}, nil
+	}
+	tryCurrents := func(names []string) (*currentFile, error) {
+		var (
+			cur *currentFile
+			// Last corruption error.
+			lastCerr error
+		)
+		for _, name := range names {
+			var err error
+			cur, err = tryCurrent(name)
+			if err == nil {
+				break
+			} else if err == os.ErrNotExist {
+				// Fallback to the next file.
+			} else if isCorrupted(err) {
+				lastCerr = err
+				// Fallback to the next file.
+			} else {
+				// In case the error is due to permission, etc.
+				return nil, err
+			}
+		}
+		if cur == nil {
+			err := os.ErrNotExist
+			if lastCerr != nil {
+				err = lastCerr
+			}
+			return nil, err
+		}
+		return cur, nil
+	}
+
+	// Try 'pending rename' files.
+	var nums []int64
+	for _, name := range names {
+		if strings.HasPrefix(name, "CURRENT.") && name != "CURRENT.bak" {
+			i, err := strconv.ParseInt(name[8:], 10, 64)
+			if err == nil {
+				nums = append(nums, i)
+			}
+		}
+	}
+	var (
+		pendCur   *currentFile
+		pendErr   = os.ErrNotExist
+		pendNames []string
+	)
+	if len(nums) > 0 {
+		sort.Sort(sort.Reverse(int64Slice(nums)))
+		pendNames = make([]string, len(nums))
+		for i, num := range nums {
+			pendNames[i] = fmt.Sprintf("CURRENT.%d", num)
+		}
+		pendCur, pendErr = tryCurrents(pendNames)
+		if pendErr != nil && pendErr != os.ErrNotExist && !isCorrupted(pendErr) {
+			return FileDesc{}, pendErr
+		}
+	}
+
+	// Try CURRENT and CURRENT.bak.
+	curCur, curErr := tryCurrents([]string{"CURRENT", "CURRENT.bak"})
+	if curErr != nil && curErr != os.ErrNotExist && !isCorrupted(curErr) {
+		return FileDesc{}, curErr
+	}
+
+	// pendCur takes precedence, but guards against obsolete pendCur.
+	if pendCur != nil && (curCur == nil || pendCur.fd.Num > curCur.fd.Num) {
+		curCur = pendCur
+	}
+
+	if curCur != nil {
+		// Restore CURRENT file to proper state.
+		if !fs.readOnly && (curCur.name != "CURRENT" || len(pendNames) != 0) {
+			// Ignore setMeta errors, however don't delete obsolete files if we
+			// catch error.
+			if err := fs.setMeta(curCur.fd); err == nil {
+				// Remove 'pending rename' files.
+				for _, name := range pendNames {
+					if err := os.Remove(filepath.Join(fs.path, name)); err != nil {
+						fs.log(fmt.Sprintf("remove %s: %v", name, err))
+					}
+				}
+			}
+		}
+		return curCur.fd, nil
+	}
+
+	// Nothing found.
+	if isCorrupted(pendErr) {
+		return FileDesc{}, pendErr
+	}
+	return FileDesc{}, curErr
+}
+
+func (fs *fileStorage) List(ft FileType) (fds []FileDesc, err error) {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return nil, ErrClosed
+	}
+	dir, err := os.Open(fs.path)
+	if err != nil {
+		return
+	}
+	names, err := dir.Readdirnames(0)
+	// Close the dir first before checking for Readdirnames error.
+	if cerr := dir.Close(); cerr != nil {
+		fs.log(fmt.Sprintf("close dir: %v", cerr))
+	}
+	if err == nil {
+		for _, name := range names {
+			if fd, ok := fsParseName(name); ok && fd.Type&ft != 0 {
+				fds = append(fds, fd)
+			}
+		}
+	}
+	return
+}
+
+func (fs *fileStorage) Open(fd FileDesc) (Reader, error) {
+	if !FileDescOk(fd) {
+		return nil, ErrInvalidFile
+	}
+
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return nil, ErrClosed
+	}
+	of, err := os.OpenFile(filepath.Join(fs.path, fsGenName(fd)), os.O_RDONLY, 0)
+	if err != nil {
+		if fsHasOldName(fd) && os.IsNotExist(err) {
+			of, err = os.OpenFile(filepath.Join(fs.path, fsGenOldName(fd)), os.O_RDONLY, 0)
+			if err == nil {
+				goto ok
+			}
+		}
+		return nil, err
+	}
+ok:
+	fs.open++
+	return &fileWrap{File: of, fs: fs, fd: fd}, nil
+}
+
+func (fs *fileStorage) Create(fd FileDesc) (Writer, error) {
+	if !FileDescOk(fd) {
+		return nil, ErrInvalidFile
+	}
+	if fs.readOnly {
+		return nil, errReadOnly
+	}
+
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return nil, ErrClosed
+	}
+	of, err := os.OpenFile(filepath.Join(fs.path, fsGenName(fd)), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
+	if err != nil {
+		return nil, err
+	}
+	fs.open++
+	return &fileWrap{File: of, fs: fs, fd: fd}, nil
+}
+
+func (fs *fileStorage) Remove(fd FileDesc) error {
+	if !FileDescOk(fd) {
+		return ErrInvalidFile
+	}
+	if fs.readOnly {
+		return errReadOnly
+	}
+
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return ErrClosed
+	}
+	err := os.Remove(filepath.Join(fs.path, fsGenName(fd)))
+	if err != nil {
+		if fsHasOldName(fd) && os.IsNotExist(err) {
+			if e1 := os.Remove(filepath.Join(fs.path, fsGenOldName(fd))); !os.IsNotExist(e1) {
+				fs.log(fmt.Sprintf("remove %s: %v (old name)", fd, err))
+				err = e1
+			}
+		} else {
+			fs.log(fmt.Sprintf("remove %s: %v", fd, err))
+		}
+	}
+	return err
+}
+
+func (fs *fileStorage) Rename(oldfd, newfd FileDesc) error {
+	if !FileDescOk(oldfd) || !FileDescOk(newfd) {
+		return ErrInvalidFile
+	}
+	if oldfd == newfd {
+		return nil
+	}
+	if fs.readOnly {
+		return errReadOnly
+	}
+
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return ErrClosed
+	}
+	return rename(filepath.Join(fs.path, fsGenName(oldfd)), filepath.Join(fs.path, fsGenName(newfd)))
+}
+
+func (fs *fileStorage) Close() error {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if fs.open < 0 {
+		return ErrClosed
+	}
+	// Clear the finalizer.
+	runtime.SetFinalizer(fs, nil)
+
+	if fs.open > 0 {
+		fs.log(fmt.Sprintf("close: warning, %d files still open", fs.open))
+	}
+	fs.open = -1
+	if fs.logw != nil {
+		fs.logw.Close()
+	}
+	return fs.flock.release()
+}
+
+type fileWrap struct {
+	*os.File
+	fs     *fileStorage
+	fd     FileDesc
+	closed bool
+}
+
+func (fw *fileWrap) Sync() error {
+	if err := fw.File.Sync(); err != nil {
+		return err
+	}
+	if fw.fd.Type == TypeManifest {
+		// Also sync parent directory if file type is manifest.
+		// See: https://code.google.com/p/leveldb/issues/detail?id=190.
+		if err := syncDir(fw.fs.path); err != nil {
+			fw.fs.log(fmt.Sprintf("syncDir: %v", err))
+			return err
+		}
+	}
+	return nil
+}
+
+func (fw *fileWrap) Close() error {
+	fw.fs.mu.Lock()
+	defer fw.fs.mu.Unlock()
+	if fw.closed {
+		return ErrClosed
+	}
+	fw.closed = true
+	fw.fs.open--
+	err := fw.File.Close()
+	if err != nil {
+		fw.fs.log(fmt.Sprintf("close %s: %v", fw.fd, err))
+	}
+	return err
+}
+
+func fsGenName(fd FileDesc) string {
+	switch fd.Type {
+	case TypeManifest:
+		return fmt.Sprintf("MANIFEST-%06d", fd.Num)
+	case TypeJournal:
+		return fmt.Sprintf("%06d.log", fd.Num)
+	case TypeTable:
+		return fmt.Sprintf("%06d.ldb", fd.Num)
+	case TypeTemp:
+		return fmt.Sprintf("%06d.tmp", fd.Num)
+	default:
+		panic("invalid file type")
+	}
+}
+
+func fsHasOldName(fd FileDesc) bool {
+	return fd.Type == TypeTable
+}
+
+func fsGenOldName(fd FileDesc) string {
+	switch fd.Type {
+	case TypeTable:
+		return fmt.Sprintf("%06d.sst", fd.Num)
+	}
+	return fsGenName(fd)
+}
+
+func fsParseName(name string) (fd FileDesc, ok bool) {
+	var tail string
+	_, err := fmt.Sscanf(name, "%d.%s", &fd.Num, &tail)
+	if err == nil {
+		switch tail {
+		case "log":
+			fd.Type = TypeJournal
+		case "ldb", "sst":
+			fd.Type = TypeTable
+		case "tmp":
+			fd.Type = TypeTemp
+		default:
+			return
+		}
+		return fd, true
+	}
+	n, _ := fmt.Sscanf(name, "MANIFEST-%d%s", &fd.Num, &tail)
+	if n == 1 {
+		fd.Type = TypeManifest
+		return fd, true
+	}
+	return
+}
+
+func fsParseNamePtr(name string, fd *FileDesc) bool {
+	_fd, ok := fsParseName(name)
+	if fd != nil {
+		*fd = _fd
+	}
+	return ok
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_nacl.go

@@ -0,0 +1,34 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build nacl
+
+package storage
+
+import (
+	"os"
+	"syscall"
+)
+
+func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
+	return nil, syscall.ENOTSUP
+}
+
+func setFileLock(f *os.File, readOnly, lock bool) error {
+	return syscall.ENOTSUP
+}
+
+func rename(oldpath, newpath string) error {
+	return syscall.ENOTSUP
+}
+
+func isErrInvalid(err error) bool {
+	return false
+}
+
+func syncDir(name string) error {
+	return syscall.ENOTSUP
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_plan9.go

@@ -0,0 +1,63 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package storage
+
+import (
+	"os"
+)
+
+type plan9FileLock struct {
+	f *os.File
+}
+
+func (fl *plan9FileLock) release() error {
+	return fl.f.Close()
+}
+
+func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
+	var (
+		flag int
+		perm os.FileMode
+	)
+	if readOnly {
+		flag = os.O_RDONLY
+	} else {
+		flag = os.O_RDWR
+		perm = os.ModeExclusive
+	}
+	f, err := os.OpenFile(path, flag, perm)
+	if os.IsNotExist(err) {
+		f, err = os.OpenFile(path, flag|os.O_CREATE, perm|0644)
+	}
+	if err != nil {
+		return
+	}
+	fl = &plan9FileLock{f: f}
+	return
+}
+
+func rename(oldpath, newpath string) error {
+	if _, err := os.Stat(newpath); err == nil {
+		if err := os.Remove(newpath); err != nil {
+			return err
+		}
+	}
+
+	return os.Rename(oldpath, newpath)
+}
+
+func syncDir(name string) error {
+	f, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	if err := f.Sync(); err != nil {
+		return err
+	}
+	return nil
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_solaris.go

@@ -0,0 +1,81 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build solaris
+
+package storage
+
+import (
+	"os"
+	"syscall"
+)
+
+type unixFileLock struct {
+	f *os.File
+}
+
+func (fl *unixFileLock) release() error {
+	if err := setFileLock(fl.f, false, false); err != nil {
+		return err
+	}
+	return fl.f.Close()
+}
+
+func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
+	var flag int
+	if readOnly {
+		flag = os.O_RDONLY
+	} else {
+		flag = os.O_RDWR
+	}
+	f, err := os.OpenFile(path, flag, 0)
+	if os.IsNotExist(err) {
+		f, err = os.OpenFile(path, flag|os.O_CREATE, 0644)
+	}
+	if err != nil {
+		return
+	}
+	err = setFileLock(f, readOnly, true)
+	if err != nil {
+		f.Close()
+		return
+	}
+	fl = &unixFileLock{f: f}
+	return
+}
+
+func setFileLock(f *os.File, readOnly, lock bool) error {
+	flock := syscall.Flock_t{
+		Type:   syscall.F_UNLCK,
+		Start:  0,
+		Len:    0,
+		Whence: 1,
+	}
+	if lock {
+		if readOnly {
+			flock.Type = syscall.F_RDLCK
+		} else {
+			flock.Type = syscall.F_WRLCK
+		}
+	}
+	return syscall.FcntlFlock(f.Fd(), syscall.F_SETLK, &flock)
+}
+
+func rename(oldpath, newpath string) error {
+	return os.Rename(oldpath, newpath)
+}
+
+func syncDir(name string) error {
+	f, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	if err := f.Sync(); err != nil {
+		return err
+	}
+	return nil
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_unix.go

@@ -0,0 +1,98 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package storage
+
+import (
+	"os"
+	"syscall"
+)
+
+type unixFileLock struct {
+	f *os.File
+}
+
+func (fl *unixFileLock) release() error {
+	if err := setFileLock(fl.f, false, false); err != nil {
+		return err
+	}
+	return fl.f.Close()
+}
+
+func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
+	var flag int
+	if readOnly {
+		flag = os.O_RDONLY
+	} else {
+		flag = os.O_RDWR
+	}
+	f, err := os.OpenFile(path, flag, 0)
+	if os.IsNotExist(err) {
+		f, err = os.OpenFile(path, flag|os.O_CREATE, 0644)
+	}
+	if err != nil {
+		return
+	}
+	err = setFileLock(f, readOnly, true)
+	if err != nil {
+		f.Close()
+		return
+	}
+	fl = &unixFileLock{f: f}
+	return
+}
+
+func setFileLock(f *os.File, readOnly, lock bool) error {
+	how := syscall.LOCK_UN
+	if lock {
+		if readOnly {
+			how = syscall.LOCK_SH
+		} else {
+			how = syscall.LOCK_EX
+		}
+	}
+	return syscall.Flock(int(f.Fd()), how|syscall.LOCK_NB)
+}
+
+func rename(oldpath, newpath string) error {
+	return os.Rename(oldpath, newpath)
+}
+
+func isErrInvalid(err error) bool {
+	if err == os.ErrInvalid {
+		return true
+	}
+	// Go < 1.8
+	if syserr, ok := err.(*os.SyscallError); ok && syserr.Err == syscall.EINVAL {
+		return true
+	}
+	// Go >= 1.8 returns *os.PathError instead
+	if patherr, ok := err.(*os.PathError); ok && patherr.Err == syscall.EINVAL {
+		return true
+	}
+	return false
+}
+
+func syncDir(name string) error {
+	// As per fsync manpage, Linux seems to expect fsync on directory, however
+	// some system don't support this, so we will ignore syscall.EINVAL.
+	//
+	// From fsync(2):
+	//   Calling fsync() does not necessarily ensure that the entry in the
+	//   directory containing the file has also reached disk. For that an
+	//   explicit fsync() on a file descriptor for the directory is also needed.
+	f, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	if err := f.Sync(); err != nil && !isErrInvalid(err) {
+		return err
+	}
+	return nil
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/file_storage_windows.go

@@ -0,0 +1,78 @@
+// Copyright (c) 2013, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package storage
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+var (
+	modkernel32 = syscall.NewLazyDLL("kernel32.dll")
+
+	procMoveFileExW = modkernel32.NewProc("MoveFileExW")
+)
+
+const (
+	_MOVEFILE_REPLACE_EXISTING = 1
+)
+
+type windowsFileLock struct {
+	fd syscall.Handle
+}
+
+func (fl *windowsFileLock) release() error {
+	return syscall.Close(fl.fd)
+}
+
+func newFileLock(path string, readOnly bool) (fl fileLock, err error) {
+	pathp, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return
+	}
+	var access, shareMode uint32
+	if readOnly {
+		access = syscall.GENERIC_READ
+		shareMode = syscall.FILE_SHARE_READ
+	} else {
+		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
+	}
+	fd, err := syscall.CreateFile(pathp, access, shareMode, nil, syscall.OPEN_EXISTING, syscall.FILE_ATTRIBUTE_NORMAL, 0)
+	if err == syscall.ERROR_FILE_NOT_FOUND {
+		fd, err = syscall.CreateFile(pathp, access, shareMode, nil, syscall.OPEN_ALWAYS, syscall.FILE_ATTRIBUTE_NORMAL, 0)
+	}
+	if err != nil {
+		return
+	}
+	fl = &windowsFileLock{fd: fd}
+	return
+}
+
+func moveFileEx(from *uint16, to *uint16, flags uint32) error {
+	r1, _, e1 := syscall.Syscall(procMoveFileExW.Addr(), 3, uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(to)), uintptr(flags))
+	if r1 == 0 {
+		if e1 != 0 {
+			return error(e1)
+		}
+		return syscall.EINVAL
+	}
+	return nil
+}
+
+func rename(oldpath, newpath string) error {
+	from, err := syscall.UTF16PtrFromString(oldpath)
+	if err != nil {
+		return err
+	}
+	to, err := syscall.UTF16PtrFromString(newpath)
+	if err != nil {
+		return err
+	}
+	return moveFileEx(from, to, _MOVEFILE_REPLACE_EXISTING)
+}
+
+func syncDir(name string) error { return nil }

vendor/github.com/syndtr/goleveldb/leveldb/storage/mem_storage.go

@@ -0,0 +1,222 @@
+// Copyright (c) 2013, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package storage
+
+import (
+	"bytes"
+	"os"
+	"sync"
+)
+
+const typeShift = 4
+
+// Verify at compile-time that typeShift is large enough to cover all FileType
+// values by confirming that 0 == 0.
+var _ [0]struct{} = [TypeAll >> typeShift]struct{}{}
+
+type memStorageLock struct {
+	ms *memStorage
+}
+
+func (lock *memStorageLock) Unlock() {
+	ms := lock.ms
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	if ms.slock == lock {
+		ms.slock = nil
+	}
+	return
+}
+
+// memStorage is a memory-backed storage.
+type memStorage struct {
+	mu    sync.Mutex
+	slock *memStorageLock
+	files map[uint64]*memFile
+	meta  FileDesc
+}
+
+// NewMemStorage returns a new memory-backed storage implementation.
+func NewMemStorage() Storage {
+	return &memStorage{
+		files: make(map[uint64]*memFile),
+	}
+}
+
+func (ms *memStorage) Lock() (Locker, error) {
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	if ms.slock != nil {
+		return nil, ErrLocked
+	}
+	ms.slock = &memStorageLock{ms: ms}
+	return ms.slock, nil
+}
+
+func (*memStorage) Log(str string) {}
+
+func (ms *memStorage) SetMeta(fd FileDesc) error {
+	if !FileDescOk(fd) {
+		return ErrInvalidFile
+	}
+
+	ms.mu.Lock()
+	ms.meta = fd
+	ms.mu.Unlock()
+	return nil
+}
+
+func (ms *memStorage) GetMeta() (FileDesc, error) {
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	if ms.meta.Zero() {
+		return FileDesc{}, os.ErrNotExist
+	}
+	return ms.meta, nil
+}
+
+func (ms *memStorage) List(ft FileType) ([]FileDesc, error) {
+	ms.mu.Lock()
+	var fds []FileDesc
+	for x := range ms.files {
+		fd := unpackFile(x)
+		if fd.Type&ft != 0 {
+			fds = append(fds, fd)
+		}
+	}
+	ms.mu.Unlock()
+	return fds, nil
+}
+
+func (ms *memStorage) Open(fd FileDesc) (Reader, error) {
+	if !FileDescOk(fd) {
+		return nil, ErrInvalidFile
+	}
+
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	if m, exist := ms.files[packFile(fd)]; exist {
+		if m.open {
+			return nil, errFileOpen
+		}
+		m.open = true
+		return &memReader{Reader: bytes.NewReader(m.Bytes()), ms: ms, m: m}, nil
+	}
+	return nil, os.ErrNotExist
+}
+
+func (ms *memStorage) Create(fd FileDesc) (Writer, error) {
+	if !FileDescOk(fd) {
+		return nil, ErrInvalidFile
+	}
+
+	x := packFile(fd)
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	m, exist := ms.files[x]
+	if exist {
+		if m.open {
+			return nil, errFileOpen
+		}
+		m.Reset()
+	} else {
+		m = &memFile{}
+		ms.files[x] = m
+	}
+	m.open = true
+	return &memWriter{memFile: m, ms: ms}, nil
+}
+
+func (ms *memStorage) Remove(fd FileDesc) error {
+	if !FileDescOk(fd) {
+		return ErrInvalidFile
+	}
+
+	x := packFile(fd)
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	if _, exist := ms.files[x]; exist {
+		delete(ms.files, x)
+		return nil
+	}
+	return os.ErrNotExist
+}
+
+func (ms *memStorage) Rename(oldfd, newfd FileDesc) error {
+	if !FileDescOk(oldfd) || !FileDescOk(newfd) {
+		return ErrInvalidFile
+	}
+	if oldfd == newfd {
+		return nil
+	}
+
+	oldx := packFile(oldfd)
+	newx := packFile(newfd)
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+	oldm, exist := ms.files[oldx]
+	if !exist {
+		return os.ErrNotExist
+	}
+	newm, exist := ms.files[newx]
+	if (exist && newm.open) || oldm.open {
+		return errFileOpen
+	}
+	delete(ms.files, oldx)
+	ms.files[newx] = oldm
+	return nil
+}
+
+func (*memStorage) Close() error { return nil }
+
+type memFile struct {
+	bytes.Buffer
+	open bool
+}
+
+type memReader struct {
+	*bytes.Reader
+	ms     *memStorage
+	m      *memFile
+	closed bool
+}
+
+func (mr *memReader) Close() error {
+	mr.ms.mu.Lock()
+	defer mr.ms.mu.Unlock()
+	if mr.closed {
+		return ErrClosed
+	}
+	mr.m.open = false
+	return nil
+}
+
+type memWriter struct {
+	*memFile
+	ms     *memStorage
+	closed bool
+}
+
+func (*memWriter) Sync() error { return nil }
+
+func (mw *memWriter) Close() error {
+	mw.ms.mu.Lock()
+	defer mw.ms.mu.Unlock()
+	if mw.closed {
+		return ErrClosed
+	}
+	mw.memFile.open = false
+	return nil
+}
+
+func packFile(fd FileDesc) uint64 {
+	return uint64(fd.Num)<<typeShift | uint64(fd.Type)
+}
+
+func unpackFile(x uint64) FileDesc {
+	return FileDesc{FileType(x) & TypeAll, int64(x >> typeShift)}
+}

vendor/github.com/syndtr/goleveldb/leveldb/storage/storage.go

@@ -0,0 +1,187 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Package storage provides storage abstraction for LevelDB.
+package storage
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+// FileType represent a file type.
+type FileType int
+
+// File types.
+const (
+	TypeManifest FileType = 1 << iota
+	TypeJournal
+	TypeTable
+	TypeTemp
+
+	TypeAll = TypeManifest | TypeJournal | TypeTable | TypeTemp
+)
+
+func (t FileType) String() string {
+	switch t {
+	case TypeManifest:
+		return "manifest"
+	case TypeJournal:
+		return "journal"
+	case TypeTable:
+		return "table"
+	case TypeTemp:
+		return "temp"
+	}
+	return fmt.Sprintf("<unknown:%d>", t)
+}
+
+// Common error.
+var (
+	ErrInvalidFile = errors.New("leveldb/storage: invalid file for argument")
+	ErrLocked      = errors.New("leveldb/storage: already locked")
+	ErrClosed      = errors.New("leveldb/storage: closed")
+)
+
+// ErrCorrupted is the type that wraps errors that indicate corruption of
+// a file. Package storage has its own type instead of using
+// errors.ErrCorrupted to prevent circular import.
+type ErrCorrupted struct {
+	Fd  FileDesc
+	Err error
+}
+
+func isCorrupted(err error) bool {
+	switch err.(type) {
+	case *ErrCorrupted:
+		return true
+	}
+	return false
+}
+
+func (e *ErrCorrupted) Error() string {
+	if !e.Fd.Zero() {
+		return fmt.Sprintf("%v [file=%v]", e.Err, e.Fd)
+	}
+	return e.Err.Error()
+}
+
+// Syncer is the interface that wraps basic Sync method.
+type Syncer interface {
+	// Sync commits the current contents of the file to stable storage.
+	Sync() error
+}
+
+// Reader is the interface that groups the basic Read, Seek, ReadAt and Close
+// methods.
+type Reader interface {
+	io.ReadSeeker
+	io.ReaderAt
+	io.Closer
+}
+
+// Writer is the interface that groups the basic Write, Sync and Close
+// methods.
+type Writer interface {
+	io.WriteCloser
+	Syncer
+}
+
+// Locker is the interface that wraps Unlock method.
+type Locker interface {
+	Unlock()
+}
+
+// FileDesc is a 'file descriptor'.
+type FileDesc struct {
+	Type FileType
+	Num  int64
+}
+
+func (fd FileDesc) String() string {
+	switch fd.Type {
+	case TypeManifest:
+		return fmt.Sprintf("MANIFEST-%06d", fd.Num)
+	case TypeJournal:
+		return fmt.Sprintf("%06d.log", fd.Num)
+	case TypeTable:
+		return fmt.Sprintf("%06d.ldb", fd.Num)
+	case TypeTemp:
+		return fmt.Sprintf("%06d.tmp", fd.Num)
+	default:
+		return fmt.Sprintf("%#x-%d", fd.Type, fd.Num)
+	}
+}
+
+// Zero returns true if fd == (FileDesc{}).
+func (fd FileDesc) Zero() bool {
+	return fd == (FileDesc{})
+}
+
+// FileDescOk returns true if fd is a valid 'file descriptor'.
+func FileDescOk(fd FileDesc) bool {
+	switch fd.Type {
+	case TypeManifest:
+	case TypeJournal:
+	case TypeTable:
+	case TypeTemp:
+	default:
+		return false
+	}
+	return fd.Num >= 0
+}
+
+// Storage is the storage. A storage instance must be safe for concurrent use.
+type Storage interface {
+	// Lock locks the storage. Any subsequent attempt to call Lock will fail
+	// until the last lock released.
+	// Caller should call Unlock method after use.
+	Lock() (Locker, error)
+
+	// Log logs a string. This is used for logging.
+	// An implementation may write to a file, stdout or simply do nothing.
+	Log(str string)
+
+	// SetMeta store 'file descriptor' that can later be acquired using GetMeta
+	// method. The 'file descriptor' should point to a valid file.
+	// SetMeta should be implemented in such way that changes should happen
+	// atomically.
+	SetMeta(fd FileDesc) error
+
+	// GetMeta returns 'file descriptor' stored in meta. The 'file descriptor'
+	// can be updated using SetMeta method.
+	// Returns os.ErrNotExist if meta doesn't store any 'file descriptor', or
+	// 'file descriptor' point to nonexistent file.
+	GetMeta() (FileDesc, error)
+
+	// List returns file descriptors that match the given file types.
+	// The file types may be OR'ed together.
+	List(ft FileType) ([]FileDesc, error)
+
+	// Open opens file with the given 'file descriptor' read-only.
+	// Returns os.ErrNotExist error if the file does not exist.
+	// Returns ErrClosed if the underlying storage is closed.
+	Open(fd FileDesc) (Reader, error)
+
+	// Create creates file with the given 'file descriptor', truncate if already
+	// exist and opens write-only.
+	// Returns ErrClosed if the underlying storage is closed.
+	Create(fd FileDesc) (Writer, error)
+
+	// Remove removes file with the given 'file descriptor'.
+	// Returns ErrClosed if the underlying storage is closed.
+	Remove(fd FileDesc) error
+
+	// Rename renames file from oldfd to newfd.
+	// Returns ErrClosed if the underlying storage is closed.
+	Rename(oldfd, newfd FileDesc) error
+
+	// Close closes the storage.
+	// It is valid to call Close multiple times. Other methods should not be
+	// called after the storage has been closed.
+	Close() error
+}