4 * This file is part of BeRTOS.
6 * Bertos is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
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12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * As a special exception, you may use this file as part of a free software
21 * library without restriction. Specifically, if other files instantiate
22 * templates or use macros or inline functions from this file, or you compile
23 * this file and link it with other files to produce an executable, this
24 * file does not by itself cause the resulting executable to be covered by
25 * the GNU General Public License. This exception does not however
26 * invalidate any other reasons why the executable file might be covered by
27 * the GNU General Public License.
29 * Copyright 2004 Develer S.r.l. (http://www.develer.com/)
32 * \brief Functions to convert integers to/from host byte-order.
34 * \author Bernie Innocenti <bernie@codewiz.org>
35 * \author Stefano Fedrigo <aleph@develer.com>
38 #ifndef MWARE_BYTEORDER_H
39 #define MWARE_BYTEORDER_H
41 #include <cfg/compiler.h>
45 * Swap upper and lower bytes in a 16-bit value.
47 INLINE uint16_t swab16(uint16_t x)
49 return ((x & (uint16_t)0x00FFU) << 8)
50 | ((x & (uint16_t)0xFF00U) >> 8);
54 * Reverse bytes in a 32-bit value (e.g.: 0x12345678 -> 0x78563412).
56 INLINE uint32_t swab32(uint32_t x)
58 return ((x & (uint32_t)0x000000FFUL) << 24)
59 | ((x & (uint32_t)0x0000FF00UL) << 8)
60 | ((x & (uint32_t)0x00FF0000UL) >> 8)
61 | ((x & (uint32_t)0xFF000000UL) >> 24);
65 * Reverse bytes in a 64-bit value.
67 INLINE uint64_t swab64(uint64_t x)
69 return (uint64_t)swab32(x >> 32)
70 | ((uint64_t)swab32(x & 0xFFFFFFFFUL) << 32);
74 * Reverse bytes in a float value.
76 INLINE float swab_float(float x)
78 /* Avoid breaking strict aliasing rules. */
79 char *cx = (char *)(&x);
80 STATIC_ASSERT(sizeof(float) == 4);
81 #define BYTEORDER_SWAP(a, b) ((a) ^= (b) ^= (a) ^= (b))
82 BYTEORDER_SWAP(cx[0], cx[3]);
83 BYTEORDER_SWAP(cx[1], cx[2]);
88 INLINE uint16_t cpu_to_be16(uint16_t x)
90 return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab16(x) : x;
93 INLINE uint16_t cpu_to_le16(uint16_t x)
95 return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab16(x) : x;
98 INLINE uint32_t cpu_to_be32(uint32_t x)
100 return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab32(x) : x;
103 INLINE uint32_t cpu_to_le32(uint32_t x)
105 return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab32(x) : x;
108 INLINE uint64_t cpu_to_be64(uint64_t x)
110 return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab64(x) : x;
113 INLINE uint64_t cpu_to_le64(uint64_t x)
115 return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab64(x) : x;
118 INLINE float cpu_to_be_float(float x)
120 return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab_float(x) : x;
123 INLINE float cpu_to_le_float(float x)
125 return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab_float(x) : x;
128 INLINE uint16_t be16_to_cpu(uint16_t x)
130 return cpu_to_be16(x);
133 INLINE uint16_t le16_to_cpu(uint16_t x)
135 return cpu_to_le16(x);
138 INLINE uint32_t be32_to_cpu(uint32_t x)
140 return cpu_to_be32(x);
143 INLINE uint32_t le32_to_cpu(uint32_t x)
145 return cpu_to_le32(x);
148 INLINE uint64_t be64_to_cpu(uint64_t x)
150 return cpu_to_be64(x);
153 INLINE uint64_t le64_to_cpu(uint64_t x)
155 return cpu_to_le64(x);
158 INLINE float be_float_to_cpu(float x)
160 return cpu_to_be_float(x);
163 INLINE float le_float_to_cpu(float x)
165 return cpu_to_le_float(x);
168 INLINE uint16_t host_to_net16(uint16_t x)
170 return cpu_to_be16(x);
173 INLINE uint16_t net_to_host16(uint16_t x)
175 return be16_to_cpu(x);
178 INLINE uint32_t host_to_net32(uint32_t x)
180 return cpu_to_be32(x);
183 INLINE uint32_t net_to_host32(uint32_t x)
185 return be32_to_cpu(x);
188 INLINE uint64_t host_to_net64(uint64_t x)
190 return cpu_to_be64(x);
193 INLINE uint64_t net_to_host64(uint64_t x)
195 return be64_to_cpu(x);
198 INLINE float host_to_net_float(float x)
200 return cpu_to_be_float(x);
203 INLINE float net_to_host_float(float x)
205 return be_float_to_cpu(x);
210 /// Type generic byte swapping.
214 template<> INLINE uint16_t swab(uint16_t x) { return swab16(x); }
215 template<> INLINE uint32_t swab(uint32_t x) { return swab32(x); }
216 template<> INLINE uint64_t swab(uint64_t x) { return swab64(x); }
217 template<> INLINE int16_t swab(int16_t x) { return static_cast<int16_t>(swab16(static_cast<uint16_t>(x))); }
218 template<> INLINE int32_t swab(int32_t x) { return static_cast<int32_t>(swab32(static_cast<uint32_t>(x))); }
219 template<> INLINE int64_t swab(int64_t x) { return static_cast<int64_t>(swab64(static_cast<uint64_t>(x))); }
220 template<> INLINE float swab(float x) { return swab_float(x); }
222 /// Type generic conversion from CPU byte order to big-endian byte order.
224 INLINE T cpu_to_be(T x)
226 return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab(x) : x;
229 /// Type generic conversion from CPU byte-order to little-endian.
231 INLINE T cpu_to_le(T x)
233 return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab(x) : x;
236 /// Type generic conversion from big endian byte-order to CPU byte order.
238 INLINE T be_to_cpu(T x)
243 /// Type generic conversion from little-endian byte order to CPU byte order.
245 INLINE T le_to_cpu(T x)
250 /// Type generic conversion from network byte order to host byte order.
252 INLINE T net_to_host(T x)
257 /// Type generic conversion from host byte order to network byte order.
259 INLINE T host_to_net(T x)
261 return net_to_host(x);
264 #endif /* __cplusplus */
266 #endif /* MWARE_BYTEORDER_H */