1/* -*- c-basic-offset: 2 -*- */
2/*
3 Copyright(C) 2011-2016 Brazil
4
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License version 2.1 as published by the Free Software Foundation.
8
9 This library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with this library; if not, write to the Free Software
16 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17*/
18
19#pragma once
20
21#include "dat.hpp"
22
23namespace grn {
24namespace dat {
25
26// The most significant bit represents whether or not the node is a linker.
27// BASE of a linker represents the position of its associated key and BASE of
28// a non-linker represents the offset to its child nodes.
29class GRN_DAT_API Base {
30 public:
31 Base() : value_(0) {}
32
33 bool operator==(const Base &rhs) const {
34 return value_ == rhs.value_;
35 }
36
37 bool is_linker() const {
38 return (value_ & IS_LINKER_FLAG) == IS_LINKER_FLAG;
39 }
40 UInt32 offset() const {
41 GRN_DAT_DEBUG_THROW_IF(is_linker());
42 return value_;
43 }
44 UInt32 key_pos() const {
45 GRN_DAT_DEBUG_THROW_IF(!is_linker());
46 return value_ & ~IS_LINKER_FLAG;
47 }
48
49 void set_offset(UInt32 x) {
50 GRN_DAT_DEBUG_THROW_IF((x & IS_LINKER_FLAG) != 0);
51 GRN_DAT_DEBUG_THROW_IF(x > MAX_OFFSET);
52 value_ = x;
53 }
54 void set_key_pos(UInt32 x) {
55 GRN_DAT_DEBUG_THROW_IF((x & IS_LINKER_FLAG) != 0);
56 GRN_DAT_DEBUG_THROW_IF(x > MAX_OFFSET);
57 value_ = IS_LINKER_FLAG | x;
58 }
59
60 private:
61 UInt32 value_;
62
63 static const UInt32 IS_LINKER_FLAG = 0x80000000U;
64};
65
66} // namespace dat
67} // namespace grn
68