1/*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17//
18
19#ifndef _LIBS_UTILS_BYTE_ORDER_H
20#define _LIBS_UTILS_BYTE_ORDER_H
21
22#include <stdint.h>
23#include <sys/types.h>
24#ifdef HAVE_WINSOCK
25#include <winsock2.h>
26#else
27#include <netinet/in.h>
28#endif
29
30/*
31 * These macros are like the hton/ntoh byte swapping macros,
32 * except they allow you to swap to and from the "device" byte
33 * order.  The device byte order is the endianness of the target
34 * device -- for the ARM CPUs we use today, this is little endian.
35 *
36 * Note that the byte swapping functions have not been optimized
37 * much; performance is currently not an issue for them since the
38 * intent is to allow us to avoid byte swapping on the device.
39 */
40
41static inline uint32_t android_swap_long(uint32_t v)
42{
43    return (v<<24) | ((v<<8)&0x00FF0000) | ((v>>8)&0x0000FF00) | (v>>24);
44}
45
46static inline uint16_t android_swap_short(uint16_t v)
47{
48    return (v<<8) | (v>>8);
49}
50
51#define DEVICE_BYTE_ORDER LITTLE_ENDIAN
52
53#if BYTE_ORDER == DEVICE_BYTE_ORDER
54
55#define	dtohl(x)	(x)
56#define	dtohs(x)	(x)
57#define	htodl(x)	(x)
58#define	htods(x)	(x)
59
60#else
61
62#define	dtohl(x)	(android_swap_long(x))
63#define	dtohs(x)	(android_swap_short(x))
64#define	htodl(x)	(android_swap_long(x))
65#define	htods(x)	(android_swap_short(x))
66
67#endif
68
69#if BYTE_ORDER == LITTLE_ENDIAN
70#define fromlel(x) (x)
71#define fromles(x) (x)
72#define tolel(x) (x)
73#define toles(x) (x)
74#else
75#define fromlel(x) (android_swap_long(x))
76#define fromles(x) (android_swap_short(x))
77#define tolel(x) (android_swap_long(x))
78#define toles(x) (android_swap_short(x))
79#endif
80
81#endif // _LIBS_UTILS_BYTE_ORDER_H
82