Exemple #1
0
func (o *Options) acidFiler(db *DB, f lldb.Filer) (r lldb.Filer, err error) {
	switch o._ACID {
	default:
		panic("internal error")
	case _ACIDTransactions:
		if r, err = lldb.NewRollbackFiler(
			f,
			func(sz int64) error {
				return f.Truncate(sz)
			},
			f,
		); err != nil {
			return nil, err
		}

		return r, nil
	case _ACIDFull:
		if r, err = lldb.NewACIDFiler(f, o.wal); err != nil {
			return nil, err
		}

		db.acidState = stIdle
		db.gracePeriod = o._GracePeriod
		if o._GracePeriod == 0 {
			panic("internal error")
		}
		return r, nil
	}
}
Exemple #2
0
func (o *Options) acidFiler(db *DB, f lldb.Filer) (r lldb.Filer, err error) {
	switch o.ACID {
	default:
		panic("internal error")
	case ACIDNone:
		r = f
	case ACIDTransactions:
		var rf *lldb.RollbackFiler
		if rf, err = lldb.NewRollbackFiler(
			f,
			func(sz int64) error {
				return f.Truncate(sz)
			},
			f,
		); err != nil {
			return
		}

		db.xact = true
		r = rf
	case ACIDFull:
		if r, err = lldb.NewACIDFiler(f, o.wal); err != nil {
			return
		}

		db.acidState = stIdle
		db.gracePeriod = o.GracePeriod
		db.xact = true
		if o.GracePeriod == 0 {
			db.acidState = stDisabled
			break
		}

		// Ensure GOMAXPROCS > 1, required for ACID FSM
		if n := runtime.GOMAXPROCS(0); n > 1 {
			return
		}

		runtime.GOMAXPROCS(2)
	}
	return
}
Exemple #3
0
func create(f *os.File, filer lldb.Filer, opts *Options, isMem bool) (db *DB, err error) {
	defer func() {
		lock := opts.lock
		if err != nil && lock != nil {
			n := lock.Name()
			lock.Close()
			os.Remove(n)
			db = nil
		}
	}()

	if err = opts.check(filer.Name(), true, !isMem); err != nil {
		return
	}

	b := [16]byte{byte(magic[0]), byte(magic[1]), byte(magic[2]), byte(magic[3]), 0x00} // ver 0x00
	if n, err := filer.WriteAt(b[:], 0); n != 16 {
		return nil, &os.PathError{Op: "dbm.Create.WriteAt", Path: filer.Name(), Err: err}
	}

	db = &DB{emptySize: 128, f: f, lock: opts.lock, closed: make(chan bool)}

	if filer, err = opts.acidFiler(db, filer); err != nil {
		return nil, err
	}

	db.filer = filer
	if err = filer.BeginUpdate(); err != nil {
		return
	}

	defer func() {
		if e := filer.EndUpdate(); e != nil {
			if err == nil {
				err = e
			}
		}
	}()

	if db.alloc, err = lldb.NewAllocator(lldb.NewInnerFiler(filer, 16), &lldb.Options{}); err != nil {
		return nil, &os.PathError{Op: "dbm.Create", Path: filer.Name(), Err: err}
	}

	db.alloc.Compress = compress
	db.isMem = isMem
	return db, db.boot()
}
Exemple #4
0
func create(f *os.File, filer lldb.Filer, opts *Options, isMem bool) (db *DB, err error) {
	defer func() {
		if db != nil {
			db.opts = opts
		}
	}()
	defer func() {
		lock := opts.lock
		if err != nil && lock != nil {
			lock.Close()
			db = nil
		}
	}()

	if err = opts.check(filer.Name(), true, !isMem); err != nil {
		return
	}

	b := [16]byte{byte(magic[0]), byte(magic[1]), byte(magic[2]), byte(magic[3]), 0x00} // ver 0x00
	if n, err := filer.WriteAt(b[:], 0); n != 16 {
		return nil, &os.PathError{Op: "kv.create.WriteAt", Path: filer.Name(), Err: err}
	}

	db = &DB{f: f, lock: opts.lock}

	if filer, err = opts.acidFiler(db, filer); err != nil {
		return nil, err
	}

	db.filer = filer
	if err = filer.BeginUpdate(); err != nil {
		return
	}

	defer func() {
		if e := filer.EndUpdate(); e != nil {
			if err == nil {
				err = e
			}
		}
	}()

	if db.alloc, err = lldb.NewAllocator(lldb.NewInnerFiler(filer, 16), &lldb.Options{}); err != nil {
		return nil, &os.PathError{Op: "kv.create", Path: filer.Name(), Err: err}
	}

	db.alloc.Compress = true
	db.isMem = isMem
	var h int64
	if db.root, h, err = lldb.CreateBTree(db.alloc, opts.Compare); err != nil {
		return
	}

	if h != 1 {
		panic("internal error")
	}

	db.wal = opts.wal
	return
}
Exemple #5
0
Fichier : kv.go Projet : miffa/kv
// OpenFromFiler is like Open but it accepts an arbitrary backing storage
// provided by filer.
func OpenFromFiler(filer lldb.Filer, opts *Options) (db *DB, err error) {
	opts = opts.clone()
	opts._ACID = _ACIDFull
	defer func() {
		if db != nil {
			db.opts = opts
		}
	}()
	defer func() {
		lock := opts.lock
		if err != nil && lock != nil {
			lock.Close()
			db = nil
		}
		if err != nil {
			if db != nil {
				db.Close()
				db = nil
			}
		}
	}()

	name := filer.Name()
	if err = opts.check(name, false, true); err != nil {
		return
	}

	sz, err := filer.Size()
	if err != nil {
		return
	}

	if sz%16 != 0 {
		return nil, &os.PathError{Op: "kv.Open:", Path: name, Err: fmt.Errorf("file size %d(%#x) is not 0 (mod 16)", sz, sz)}
	}

	var b [16]byte
	if n, err := filer.ReadAt(b[:], 0); n != 16 || err != nil {
		return nil, &os.PathError{Op: "kv.Open.ReadAt", Path: name, Err: err}
	}

	var h header
	if err = h.rd(b[:]); err != nil {
		return nil, &os.PathError{Op: "kv.Open:validate header", Path: name, Err: err}
	}

	db = &DB{lock: opts.lock}
	if filer, err = opts.acidFiler(db, filer); err != nil {
		return nil, err
	}

	db.filer = filer
	switch h.ver {
	default:
		return nil, &os.PathError{Op: "kv.Open", Path: name, Err: fmt.Errorf("unknown/unsupported kv file format version %#x", h.ver)}
	case 0x00:
		if _, err = open00(name, db); err != nil {
			return nil, err
		}
	}

	db.root, err = lldb.OpenBTree(db.alloc, opts.Compare, 1)
	db.wal = opts.wal
	if opts.VerifyDbAfterOpen {
		err = verifyAllocator(db.alloc)
	}
	return
}