projects / pub / USBasp.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Added new CALLBACK_Audio_Device_GetSetInterfaceProperty() callback to the Audio Devic...
[pub/USBasp.git] / LUFA / Common / Endianness.h
1 /*
2 LUFA Library
3 Copyright (C) Dean Camera, 2011.
4
5 dean [at] fourwalledcubicle [dot] com
6 www.lufa-lib.org
7 */
8
9 /*
10 Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com)
11
12 Permission to use, copy, modify, distribute, and sell this
13 software and its documentation for any purpose is hereby granted
14 without fee, provided that the above copyright notice appear in
15 all copies and that both that the copyright notice and this
16 permission notice and warranty disclaimer appear in supporting
17 documentation, and that the name of the author not be used in
18 advertising or publicity pertaining to distribution of the
19 software without specific, written prior permission.
20
21 The author disclaim all warranties with regard to this
22 software, including all implied warranties of merchantability
23 and fitness. In no event shall the author be liable for any
24 special, indirect or consequential damages or any damages
25 whatsoever resulting from loss of use, data or profits, whether
26 in an action of contract, negligence or other tortious action,
27 arising out of or in connection with the use or performance of
28 this software.
29 */
30
31 /** \file
32 * \brief Endianness and Byte Ordering macros and functions.
33 *
34 * \copydetails Group_Endianness
35 */
36
37 /** \ingroup Group_Endianness
38 * \defgroup Group_ByteSwapping Byte Reordering
39 * \brief Macros and functions for forced byte reordering.
40 */
41
42 /** \ingroup Group_Endianness
43 * \defgroup Group_EndianConversion Endianness Conversion
44 * \brief Macros and functions for automatic endianness conversion.
45 */
46
47 /** \ingroup Group_Common
48 * \defgroup Group_Endianness Endianness and Byte Ordering
49 * \brief Convenience macros and functions relating to byte (re-)ordering
50 *
51 * Common library convenience macros and functions relating to byte (re-)ordering.
52 *
53 * @{
54 */
55
56 #ifndef __LUFA_ENDIANNESS_H__
57 #define __LUFA_ENDIANNESS_H__
58
59 /* Enable C linkage for C++ Compilers: */
60 #if defined(__cplusplus)
61 extern "C" {
62 #endif
63
64 /* Preprocessor Checks: */
65 #if !defined(__INCLUDE_FROM_COMMON_H)
66 #error Do not include this file directly. Include LUFA/Common/Common.h instead to gain this functionality.
67 #endif
68
69 #if !(defined(ARCH_BIG_ENDIAN) || defined(ARCH_LITTLE_ENDIAN))
70 #error ARCH_BIG_ENDIAN or ARCH_LITTLE_ENDIAN not set for the specified architecture.
71 #endif
72
73 /* Public Interface - May be used in end-application: */
74 /* Macros: */
75 /** Swaps the byte ordering of a 16-bit value at compile-time. Do not use this macro for swapping byte orderings
76 * of dynamic values computed at runtime, use \ref SwapEndian_16() instead. The result of this macro can be used
77 * inside struct or other variable initializers outside of a function, something that is not possible with the
78 * inline function variant.
79 *
80 * \ingroup Group_ByteSwapping
81 *
82 * \param[in] x 16-bit value whose byte ordering is to be swapped.
83 *
84 * \return Input value with the byte ordering reversed.
85 */
86 #define SWAPENDIAN_16(x) (uint16_t)((((x) & 0xFF00) >> 8) | (((x) & 0x00FF) << 8))
87
88 /** Swaps the byte ordering of a 32-bit value at compile-time. Do not use this macro for swapping byte orderings
89 * of dynamic values computed at runtime- use \ref SwapEndian_32() instead. The result of this macro can be used
90 * inside struct or other variable initializers outside of a function, something that is not possible with the
91 * inline function variant.
92 *
93 * \ingroup Group_ByteSwapping
94 *
95 * \param[in] x 32-bit value whose byte ordering is to be swapped.
96 *
97 * \return Input value with the byte ordering reversed.
98 */
99 #define SWAPENDIAN_32(x) (uint32_t)((((x) & 0xFF000000UL) >> 24UL) | (((x) & 0x00FF0000UL) >> 8UL) | \
100 (((x) & 0x0000FF00UL) << 8UL) | (((x) & 0x000000FFUL) << 24UL))
101
102 #if defined(ARCH_BIG_ENDIAN) && !defined(le16_to_cpu)
103 #define le16_to_cpu(x) SwapEndian_16(x)
104 #define le32_to_cpu(x) SwapEndian_32(x)
105 #define be16_to_cpu(x) (x)
106 #define be32_to_cpu(x) (x)
107 #define cpu_to_le16(x) SwapEndian_16(x)
108 #define cpu_to_le32(x) SwapEndian_32(x)
109 #define cpu_to_be16(x) (x)
110 #define cpu_to_be32(x) (x)
111 #define LE16_TO_CPU(x) SWAPENDIAN_16(x)
112 #define LE32_TO_CPU(x) SWAPENDIAN_32(x)
113 #define BE16_TO_CPU(x) (x)
114 #define BE32_TO_CPU(x) (x)
115 #define CPU_TO_LE16(x) SWAPENDIAN_16(x)
116 #define CPU_TO_LE32(x) SWAPENDIAN_32(x)
117 #define CPU_TO_BE16(x) (x)
118 #define CPU_TO_BE32(x) (x)
119 #elif !defined(le16_to_cpu)
120 /** \name Run-time endianness conversion */
121 //@{
122
123 /** Performs a conversion between a Little Endian encoded 16-bit piece of data and the
124 * Endianness of the currently selected CPU architecture.
125 *
126 * On little endian architectures, this macro does nothing.
127 *
128 * \note This macro is designed for run-time conversion of data - for compile-time endianness
129 * conversion, use \ref LE16_TO_CPU instead.
130 *
131 * \ingroup Group_EndianConversion
132 *
133 * \param[in] x Data to perform the endianness conversion on.
134 *
135 * \return Endian corrected version of the input value.
136 */
137 #define le16_to_cpu(x) (x)
138
139 /** Performs a conversion between a Little Endian encoded 32-bit piece of data and the
140 * Endianness of the currently selected CPU architecture.
141 *
142 * On little endian architectures, this macro does nothing.
143 *
144 * \note This macro is designed for run-time conversion of data - for compile-time endianness
145 * conversion, use \ref LE32_TO_CPU instead.
146 *
147 * \ingroup Group_EndianConversion
148 *
149 * \param[in] x Data to perform the endianness conversion on.
150 *
151 * \return Endian corrected version of the input value.
152 */
153 #define le32_to_cpu(x) (x)
154
155 /** Performs a conversion between a Big Endian encoded 16-bit piece of data and the
156 * Endianness of the currently selected CPU architecture.
157 *
158 * On big endian architectures, this macro does nothing.
159 *
160 * \note This macro is designed for run-time conversion of data - for compile-time endianness
161 * conversion, use \ref BE16_TO_CPU instead.
162 *
163 * \ingroup Group_EndianConversion
164 *
165 * \param[in] x Data to perform the endianness conversion on.
166 *
167 * \return Endian corrected version of the input value.
168 */
169 #define be16_to_cpu(x) SwapEndian_16(x)
170
171 /** Performs a conversion between a Big Endian encoded 32-bit piece of data and the
172 * Endianness of the currently selected CPU architecture.
173 *
174 * On big endian architectures, this macro does nothing.
175 *
176 * \note This macro is designed for run-time conversion of data - for compile-time endianness
177 * conversion, use \ref BE32_TO_CPU instead.
178 *
179 * \ingroup Group_EndianConversion
180 *
181 * \param[in] x Data to perform the endianness conversion on.
182 *
183 * \return Endian corrected version of the input value.
184 */
185 #define be32_to_cpu(x) SwapEndian_32(x)
186
187 /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it
188 * is in Little Endian format regardless of the currently selected CPU architecture.
189 *
190 * On little endian architectures, this macro does nothing.
191 *
192 * \note This macro is designed for run-time conversion of data - for compile-time endianness
193 * conversion, use \ref CPU_TO_LE16 instead.
194 *
195 * \ingroup Group_EndianConversion
196 *
197 * \param[in] x Data to perform the endianness conversion on.
198 *
199 * \return Endian corrected version of the input value.
200 */
201 #define cpu_to_le16(x) (x)
202
203 /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it
204 * is in Little Endian format regardless of the currently selected CPU architecture.
205 *
206 * On little endian architectures, this macro does nothing.
207 *
208 * \note This macro is designed for run-time conversion of data - for compile-time endianness
209 * conversion, use \ref CPU_TO_LE32 instead.
210 *
211 * \ingroup Group_EndianConversion
212 *
213 * \param[in] x Data to perform the endianness conversion on.
214 *
215 * \return Endian corrected version of the input value.
216 */
217 #define cpu_to_le32(x) (x)
218
219 /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it
220 * is in Big Endian format regardless of the currently selected CPU architecture.
221 *
222 * On big endian architectures, this macro does nothing.
223 *
224 * \note This macro is designed for run-time conversion of data - for compile-time endianness
225 * conversion, use \ref CPU_TO_BE16 instead.
226 *
227 * \ingroup Group_EndianConversion
228 *
229 * \param[in] x Data to perform the endianness conversion on.
230 *
231 * \return Endian corrected version of the input value.
232 */
233 #define cpu_to_be16(x) SwapEndian_16(x)
234
235 /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it
236 * is in Big Endian format regardless of the currently selected CPU architecture.
237 *
238 * On big endian architectures, this macro does nothing.
239 *
240 * \note This macro is designed for run-time conversion of data - for compile-time endianness
241 * conversion, use \ref CPU_TO_BE32 instead.
242 *
243 * \ingroup Group_EndianConversion
244 *
245 * \param[in] x Data to perform the endianness conversion on.
246 *
247 * \return Endian corrected version of the input value.
248 */
249 #define cpu_to_be32(x) SwapEndian_32(x)
250
251 //@}
252
253 /** \name Compile-time endianness conversion */
254 //@{
255
256 /** Performs a conversion between a Little Endian encoded 16-bit piece of data and the
257 * Endianness of the currently selected CPU architecture.
258 *
259 * On little endian architectures, this macro does nothing.
260 *
261 * \note This macro is designed for compile-time conversion of data - for run time endianness
262 * conversion, use \ref le16_to_cpu instead.
263 *
264 * \ingroup Group_EndianConversion
265 *
266 * \param[in] x Data to perform the endianness conversion on.
267 *
268 * \return Endian corrected version of the input value.
269 */
270 #define LE16_TO_CPU(x) (x)
271
272 /** Performs a conversion between a Little Endian encoded 32-bit piece of data and the
273 * Endianness of the currently selected CPU architecture.
274 *
275 * On little endian architectures, this macro does nothing.
276 *
277 * \note This macro is designed for compile-time conversion of data - for run time endianness
278 * conversion, use \ref le32_to_cpu instead.
279 *
280 * \ingroup Group_EndianConversion
281 *
282 * \param[in] x Data to perform the endianness conversion on.
283 *
284 * \return Endian corrected version of the input value.
285 */
286 #define LE32_TO_CPU(x) (x)
287
288 /** Performs a conversion between a Big Endian encoded 16-bit piece of data and the
289 * Endianness of the currently selected CPU architecture.
290 *
291 * On big endian architectures, this macro does nothing.
292 *
293 * \note This macro is designed for compile-time conversion of data - for run-time endianness
294 * conversion, use \ref be16_to_cpu instead.
295 *
296 * \ingroup Group_EndianConversion
297 *
298 * \param[in] x Data to perform the endianness conversion on.
299 *
300 * \return Endian corrected version of the input value.
301 */
302 #define BE16_TO_CPU(x) SWAPENDIAN_16(x)
303
304 /** Performs a conversion between a Big Endian encoded 32-bit piece of data and the
305 * Endianness of the currently selected CPU architecture.
306 *
307 * On big endian architectures, this macro does nothing.
308 *
309 * \note This macro is designed for compile-time conversion of data - for run-time endianness
310 * conversion, use \ref be32_to_cpu instead.
311 *
312 * \ingroup Group_EndianConversion
313 *
314 * \param[in] x Data to perform the endianness conversion on.
315 *
316 * \return Endian corrected version of the input value.
317 */
318 #define BE32_TO_CPU(x) SWAPENDIAN_32(x)
319
320 /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it
321 * is in Little Endian format regardless of the currently selected CPU architecture.
322 *
323 * On little endian architectures, this macro does nothing.
324 *
325 * \note This macro is designed for compile-time conversion of data - for run-time endianness
326 * conversion, use \ref cpu_to_le16 instead.
327 *
328 * \ingroup Group_EndianConversion
329 *
330 * \param[in] x Data to perform the endianness conversion on.
331 *
332 * \return Endian corrected version of the input value.
333 */
334 #define CPU_TO_LE16(x) (x)
335
336 /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it
337 * is in Little Endian format regardless of the currently selected CPU architecture.
338 *
339 * On little endian architectures, this macro does nothing.
340 *
341 * \note This macro is designed for compile-time conversion of data - for run-time endianness
342 * conversion, use \ref cpu_to_le32 instead.
343 *
344 * \ingroup Group_EndianConversion
345 *
346 * \param[in] x Data to perform the endianness conversion on.
347 *
348 * \return Endian corrected version of the input value.
349 */
350 #define CPU_TO_LE32(x) (x)
351
352 /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it
353 * is in Big Endian format regardless of the currently selected CPU architecture.
354 *
355 * On big endian architectures, this macro does nothing.
356 *
357 * \note This macro is designed for compile-time conversion of data - for run-time endianness
358 * conversion, use \ref cpu_to_be16 instead.
359 *
360 * \ingroup Group_EndianConversion
361 *
362 * \param[in] x Data to perform the endianness conversion on.
363 *
364 * \return Endian corrected version of the input value.
365 */
366 #define CPU_TO_BE16(x) SWAPENDIAN_16(x)
367
368 /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it
369 * is in Big Endian format regardless of the currently selected CPU architecture.
370 *
371 * On big endian architectures, this macro does nothing.
372 *
373 * \note This macro is designed for compile-time conversion of data - for run-time endianness
374 * conversion, use \ref cpu_to_be32 instead.
375 *
376 * \ingroup Group_EndianConversion
377 *
378 * \param[in] x Data to perform the endianness conversion on.
379 *
380 * \return Endian corrected version of the input value.
381 */
382 #define CPU_TO_BE32(x) SWAPENDIAN_32(x)
383
384 //! @}
385 #endif
386
387 /* Inline Functions: */
388 /** Function to reverse the byte ordering of the individual bytes in a 16 bit value.
389 *
390 * \ingroup Group_ByteSwapping
391 *
392 * \param[in] Word Word of data whose bytes are to be swapped.
393 *
394 * \return Input data with the individual bytes reversed.
395 */
396 static inline uint16_t SwapEndian_16(const uint16_t Word) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
397 static inline uint16_t SwapEndian_16(const uint16_t Word)
398 {
399 if (GCC_IS_COMPILE_CONST(Word))
400 return SWAPENDIAN_16(Word);
401
402 uint8_t Temp;
403
404 union
405 {
406 uint16_t Word;
407 uint8_t Bytes[2];
408 } Data;
409
410 Data.Word = Word;
411
412 Temp = Data.Bytes[0];
413 Data.Bytes[0] = Data.Bytes[1];
414 Data.Bytes[1] = Temp;
415
416 return Data.Word;
417 }
418
419 /** Function to reverse the byte ordering of the individual bytes in a 32 bit value.
420 *
421 * \ingroup Group_ByteSwapping
422 *
423 * \param[in] DWord Double word of data whose bytes are to be swapped.
424 *
425 * \return Input data with the individual bytes reversed.
426 */
427 static inline uint32_t SwapEndian_32(const uint32_t DWord) ATTR_WARN_UNUSED_RESULT ATTR_CONST;
428 static inline uint32_t SwapEndian_32(const uint32_t DWord)
429 {
430 if (GCC_IS_COMPILE_CONST(DWord))
431 return SWAPENDIAN_32(DWord);
432
433 uint8_t Temp;
434
435 union
436 {
437 uint32_t DWord;
438 uint8_t Bytes[4];
439 } Data;
440
441 Data.DWord = DWord;
442
443 Temp = Data.Bytes[0];
444 Data.Bytes[0] = Data.Bytes[3];
445 Data.Bytes[3] = Temp;
446
447 Temp = Data.Bytes[1];
448 Data.Bytes[1] = Data.Bytes[2];
449 Data.Bytes[2] = Temp;
450
451 return Data.DWord;
452 }
453
454 /** Function to reverse the byte ordering of the individual bytes in a n byte value.
455 *
456 * \ingroup Group_ByteSwapping
457 *
458 * \param[in,out] Data Pointer to a number containing an even number of bytes to be reversed.
459 * \param[in] Length Length of the data in bytes.
460 *
461 * \return Input data with the individual bytes reversed.
462 */
463 static inline void SwapEndian_n(void* const Data,
464 uint8_t Length) ATTR_NON_NULL_PTR_ARG(1);
465 static inline void SwapEndian_n(void* const Data,
466 uint8_t Length)
467 {
468 uint8_t* CurrDataPos = (uint8_t*)Data;
469
470 while (Length > 1)
471 {
472 uint8_t Temp = *CurrDataPos;
473 *CurrDataPos = *(CurrDataPos + Length - 1);
474 *(CurrDataPos + Length - 1) = Temp;
475
476 CurrDataPos++;
477 Length -= 2;
478 }
479 }
480
481 /* Disable C linkage for C++ Compilers: */
482 #if defined(__cplusplus)
483 }
484 #endif
485
486 #endif
487
488 /** @} */
489
USB isp AVR programmer