1/*
2 *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef WEBRTC_BASE_BYTEORDER_H_
12#define WEBRTC_BASE_BYTEORDER_H_
13
14#if defined(WEBRTC_POSIX) && !defined(__native_client__)
15#include <arpa/inet.h>
16#endif
17
18#if defined(WEBRTC_WIN)
19#include <stdlib.h>
20#endif
21
22#include "webrtc/base/basictypes.h"
23
24namespace rtc {
25
26// Reading and writing of little and big-endian numbers from memory
27// TODO: Optimized versions, with direct read/writes of
28// integers in host-endian format, when the platform supports it.
29
30inline void Set8(void* memory, size_t offset, uint8_t v) {
31  static_cast<uint8_t*>(memory)[offset] = v;
32}
33
34inline uint8_t Get8(const void* memory, size_t offset) {
35  return static_cast<const uint8_t*>(memory)[offset];
36}
37
38inline void SetBE16(void* memory, uint16_t v) {
39  Set8(memory, 0, static_cast<uint8_t>(v >> 8));
40  Set8(memory, 1, static_cast<uint8_t>(v >> 0));
41}
42
43inline void SetBE32(void* memory, uint32_t v) {
44  Set8(memory, 0, static_cast<uint8_t>(v >> 24));
45  Set8(memory, 1, static_cast<uint8_t>(v >> 16));
46  Set8(memory, 2, static_cast<uint8_t>(v >> 8));
47  Set8(memory, 3, static_cast<uint8_t>(v >> 0));
48}
49
50inline void SetBE64(void* memory, uint64_t v) {
51  Set8(memory, 0, static_cast<uint8_t>(v >> 56));
52  Set8(memory, 1, static_cast<uint8_t>(v >> 48));
53  Set8(memory, 2, static_cast<uint8_t>(v >> 40));
54  Set8(memory, 3, static_cast<uint8_t>(v >> 32));
55  Set8(memory, 4, static_cast<uint8_t>(v >> 24));
56  Set8(memory, 5, static_cast<uint8_t>(v >> 16));
57  Set8(memory, 6, static_cast<uint8_t>(v >> 8));
58  Set8(memory, 7, static_cast<uint8_t>(v >> 0));
59}
60
61inline uint16_t GetBE16(const void* memory) {
62  return static_cast<uint16_t>((Get8(memory, 0) << 8) | (Get8(memory, 1) << 0));
63}
64
65inline uint32_t GetBE32(const void* memory) {
66  return (static_cast<uint32_t>(Get8(memory, 0)) << 24) |
67         (static_cast<uint32_t>(Get8(memory, 1)) << 16) |
68         (static_cast<uint32_t>(Get8(memory, 2)) << 8) |
69         (static_cast<uint32_t>(Get8(memory, 3)) << 0);
70}
71
72inline uint64_t GetBE64(const void* memory) {
73  return (static_cast<uint64_t>(Get8(memory, 0)) << 56) |
74         (static_cast<uint64_t>(Get8(memory, 1)) << 48) |
75         (static_cast<uint64_t>(Get8(memory, 2)) << 40) |
76         (static_cast<uint64_t>(Get8(memory, 3)) << 32) |
77         (static_cast<uint64_t>(Get8(memory, 4)) << 24) |
78         (static_cast<uint64_t>(Get8(memory, 5)) << 16) |
79         (static_cast<uint64_t>(Get8(memory, 6)) << 8) |
80         (static_cast<uint64_t>(Get8(memory, 7)) << 0);
81}
82
83inline void SetLE16(void* memory, uint16_t v) {
84  Set8(memory, 0, static_cast<uint8_t>(v >> 0));
85  Set8(memory, 1, static_cast<uint8_t>(v >> 8));
86}
87
88inline void SetLE32(void* memory, uint32_t v) {
89  Set8(memory, 0, static_cast<uint8_t>(v >> 0));
90  Set8(memory, 1, static_cast<uint8_t>(v >> 8));
91  Set8(memory, 2, static_cast<uint8_t>(v >> 16));
92  Set8(memory, 3, static_cast<uint8_t>(v >> 24));
93}
94
95inline void SetLE64(void* memory, uint64_t v) {
96  Set8(memory, 0, static_cast<uint8_t>(v >> 0));
97  Set8(memory, 1, static_cast<uint8_t>(v >> 8));
98  Set8(memory, 2, static_cast<uint8_t>(v >> 16));
99  Set8(memory, 3, static_cast<uint8_t>(v >> 24));
100  Set8(memory, 4, static_cast<uint8_t>(v >> 32));
101  Set8(memory, 5, static_cast<uint8_t>(v >> 40));
102  Set8(memory, 6, static_cast<uint8_t>(v >> 48));
103  Set8(memory, 7, static_cast<uint8_t>(v >> 56));
104}
105
106inline uint16_t GetLE16(const void* memory) {
107  return static_cast<uint16_t>((Get8(memory, 0) << 0) | (Get8(memory, 1) << 8));
108}
109
110inline uint32_t GetLE32(const void* memory) {
111  return (static_cast<uint32_t>(Get8(memory, 0)) << 0) |
112         (static_cast<uint32_t>(Get8(memory, 1)) << 8) |
113         (static_cast<uint32_t>(Get8(memory, 2)) << 16) |
114         (static_cast<uint32_t>(Get8(memory, 3)) << 24);
115}
116
117inline uint64_t GetLE64(const void* memory) {
118  return (static_cast<uint64_t>(Get8(memory, 0)) << 0) |
119         (static_cast<uint64_t>(Get8(memory, 1)) << 8) |
120         (static_cast<uint64_t>(Get8(memory, 2)) << 16) |
121         (static_cast<uint64_t>(Get8(memory, 3)) << 24) |
122         (static_cast<uint64_t>(Get8(memory, 4)) << 32) |
123         (static_cast<uint64_t>(Get8(memory, 5)) << 40) |
124         (static_cast<uint64_t>(Get8(memory, 6)) << 48) |
125         (static_cast<uint64_t>(Get8(memory, 7)) << 56);
126}
127
128// Check if the current host is big endian.
129inline bool IsHostBigEndian() {
130  static const int number = 1;
131  return 0 == *reinterpret_cast<const char*>(&number);
132}
133
134inline uint16_t HostToNetwork16(uint16_t n) {
135  uint16_t result;
136  SetBE16(&result, n);
137  return result;
138}
139
140inline uint32_t HostToNetwork32(uint32_t n) {
141  uint32_t result;
142  SetBE32(&result, n);
143  return result;
144}
145
146inline uint64_t HostToNetwork64(uint64_t n) {
147  uint64_t result;
148  SetBE64(&result, n);
149  return result;
150}
151
152inline uint16_t NetworkToHost16(uint16_t n) {
153  return GetBE16(&n);
154}
155
156inline uint32_t NetworkToHost32(uint32_t n) {
157  return GetBE32(&n);
158}
159
160inline uint64_t NetworkToHost64(uint64_t n) {
161  return GetBE64(&n);
162}
163
164}  // namespace rtc
165
166#endif  // WEBRTC_BASE_BYTEORDER_H_
167