intreadwrite.h
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * Libav 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 Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVUTIL_INTREADWRITE_H
20 #define AVUTIL_INTREADWRITE_H
21 
22 #include <stdint.h>
23 #include "libavutil/avconfig.h"
24 #include "attributes.h"
25 #include "bswap.h"
26 
27 typedef union {
28  uint64_t u64;
29  uint32_t u32[2];
30  uint16_t u16[4];
31  uint8_t u8 [8];
32  double f64;
33  float f32[2];
34 } av_alias av_alias64;
35 
36 typedef union {
37  uint32_t u32;
38  uint16_t u16[2];
39  uint8_t u8 [4];
40  float f32;
41 } av_alias av_alias32;
42 
43 typedef union {
44  uint16_t u16;
45  uint8_t u8 [2];
46 } av_alias av_alias16;
47 
48 /*
49  * Arch-specific headers can provide any combination of
50  * AV_[RW][BLN](16|24|32|64) and AV_(COPY|SWAP|ZERO)(64|128) macros.
51  * Preprocessor symbols must be defined, even if these are implemented
52  * as inline functions.
53  */
54 
55 #ifdef HAVE_AV_CONFIG_H
56 
57 #include "config.h"
58 
59 #if ARCH_ARM
60 # include "arm/intreadwrite.h"
61 #elif ARCH_AVR32
62 # include "avr32/intreadwrite.h"
63 #elif ARCH_MIPS
64 # include "mips/intreadwrite.h"
65 #elif ARCH_PPC
66 # include "ppc/intreadwrite.h"
67 #elif ARCH_TOMI
68 # include "tomi/intreadwrite.h"
69 #elif ARCH_X86
70 # include "x86/intreadwrite.h"
71 #endif
72 
73 #endif /* HAVE_AV_CONFIG_H */
74 
75 /*
76  * Map AV_RNXX <-> AV_R[BL]XX for all variants provided by per-arch headers.
77  */
78 
79 #if AV_HAVE_BIGENDIAN
80 
81 # if defined(AV_RN16) && !defined(AV_RB16)
82 # define AV_RB16(p) AV_RN16(p)
83 # elif !defined(AV_RN16) && defined(AV_RB16)
84 # define AV_RN16(p) AV_RB16(p)
85 # endif
86 
87 # if defined(AV_WN16) && !defined(AV_WB16)
88 # define AV_WB16(p, v) AV_WN16(p, v)
89 # elif !defined(AV_WN16) && defined(AV_WB16)
90 # define AV_WN16(p, v) AV_WB16(p, v)
91 # endif
92 
93 # if defined(AV_RN24) && !defined(AV_RB24)
94 # define AV_RB24(p) AV_RN24(p)
95 # elif !defined(AV_RN24) && defined(AV_RB24)
96 # define AV_RN24(p) AV_RB24(p)
97 # endif
98 
99 # if defined(AV_WN24) && !defined(AV_WB24)
100 # define AV_WB24(p, v) AV_WN24(p, v)
101 # elif !defined(AV_WN24) && defined(AV_WB24)
102 # define AV_WN24(p, v) AV_WB24(p, v)
103 # endif
104 
105 # if defined(AV_RN32) && !defined(AV_RB32)
106 # define AV_RB32(p) AV_RN32(p)
107 # elif !defined(AV_RN32) && defined(AV_RB32)
108 # define AV_RN32(p) AV_RB32(p)
109 # endif
110 
111 # if defined(AV_WN32) && !defined(AV_WB32)
112 # define AV_WB32(p, v) AV_WN32(p, v)
113 # elif !defined(AV_WN32) && defined(AV_WB32)
114 # define AV_WN32(p, v) AV_WB32(p, v)
115 # endif
116 
117 # if defined(AV_RN64) && !defined(AV_RB64)
118 # define AV_RB64(p) AV_RN64(p)
119 # elif !defined(AV_RN64) && defined(AV_RB64)
120 # define AV_RN64(p) AV_RB64(p)
121 # endif
122 
123 # if defined(AV_WN64) && !defined(AV_WB64)
124 # define AV_WB64(p, v) AV_WN64(p, v)
125 # elif !defined(AV_WN64) && defined(AV_WB64)
126 # define AV_WN64(p, v) AV_WB64(p, v)
127 # endif
128 
129 #else /* AV_HAVE_BIGENDIAN */
130 
131 # if defined(AV_RN16) && !defined(AV_RL16)
132 # define AV_RL16(p) AV_RN16(p)
133 # elif !defined(AV_RN16) && defined(AV_RL16)
134 # define AV_RN16(p) AV_RL16(p)
135 # endif
136 
137 # if defined(AV_WN16) && !defined(AV_WL16)
138 # define AV_WL16(p, v) AV_WN16(p, v)
139 # elif !defined(AV_WN16) && defined(AV_WL16)
140 # define AV_WN16(p, v) AV_WL16(p, v)
141 # endif
142 
143 # if defined(AV_RN24) && !defined(AV_RL24)
144 # define AV_RL24(p) AV_RN24(p)
145 # elif !defined(AV_RN24) && defined(AV_RL24)
146 # define AV_RN24(p) AV_RL24(p)
147 # endif
148 
149 # if defined(AV_WN24) && !defined(AV_WL24)
150 # define AV_WL24(p, v) AV_WN24(p, v)
151 # elif !defined(AV_WN24) && defined(AV_WL24)
152 # define AV_WN24(p, v) AV_WL24(p, v)
153 # endif
154 
155 # if defined(AV_RN32) && !defined(AV_RL32)
156 # define AV_RL32(p) AV_RN32(p)
157 # elif !defined(AV_RN32) && defined(AV_RL32)
158 # define AV_RN32(p) AV_RL32(p)
159 # endif
160 
161 # if defined(AV_WN32) && !defined(AV_WL32)
162 # define AV_WL32(p, v) AV_WN32(p, v)
163 # elif !defined(AV_WN32) && defined(AV_WL32)
164 # define AV_WN32(p, v) AV_WL32(p, v)
165 # endif
166 
167 # if defined(AV_RN64) && !defined(AV_RL64)
168 # define AV_RL64(p) AV_RN64(p)
169 # elif !defined(AV_RN64) && defined(AV_RL64)
170 # define AV_RN64(p) AV_RL64(p)
171 # endif
172 
173 # if defined(AV_WN64) && !defined(AV_WL64)
174 # define AV_WL64(p, v) AV_WN64(p, v)
175 # elif !defined(AV_WN64) && defined(AV_WL64)
176 # define AV_WN64(p, v) AV_WL64(p, v)
177 # endif
178 
179 #endif /* !AV_HAVE_BIGENDIAN */
180 
181 /*
182  * Define AV_[RW]N helper macros to simplify definitions not provided
183  * by per-arch headers.
184  */
185 
186 #if defined(__GNUC__) && !defined(__TI_COMPILER_VERSION__)
187 
188 union unaligned_64 { uint64_t l; } __attribute__((packed)) av_alias;
189 union unaligned_32 { uint32_t l; } __attribute__((packed)) av_alias;
190 union unaligned_16 { uint16_t l; } __attribute__((packed)) av_alias;
191 
192 # define AV_RN(s, p) (((const union unaligned_##s *) (p))->l)
193 # define AV_WN(s, p, v) ((((union unaligned_##s *) (p))->l) = (v))
194 
195 #elif defined(__DECC)
196 
197 # define AV_RN(s, p) (*((const __unaligned uint##s##_t*)(p)))
198 # define AV_WN(s, p, v) (*((__unaligned uint##s##_t*)(p)) = (v))
199 
200 #elif AV_HAVE_FAST_UNALIGNED
201 
202 # define AV_RN(s, p) (((const av_alias##s*)(p))->u##s)
203 # define AV_WN(s, p, v) (((av_alias##s*)(p))->u##s = (v))
204 
205 #else
206 
207 #ifndef AV_RB16
208 # define AV_RB16(x) \
209  ((((const uint8_t*)(x))[0] << 8) | \
210  ((const uint8_t*)(x))[1])
211 #endif
212 #ifndef AV_WB16
213 # define AV_WB16(p, d) do { \
214  ((uint8_t*)(p))[1] = (d); \
215  ((uint8_t*)(p))[0] = (d)>>8; \
216  } while(0)
217 #endif
218 
219 #ifndef AV_RL16
220 # define AV_RL16(x) \
221  ((((const uint8_t*)(x))[1] << 8) | \
222  ((const uint8_t*)(x))[0])
223 #endif
224 #ifndef AV_WL16
225 # define AV_WL16(p, d) do { \
226  ((uint8_t*)(p))[0] = (d); \
227  ((uint8_t*)(p))[1] = (d)>>8; \
228  } while(0)
229 #endif
230 
231 #ifndef AV_RB32
232 # define AV_RB32(x) \
233  (((uint32_t)((const uint8_t*)(x))[0] << 24) | \
234  (((const uint8_t*)(x))[1] << 16) | \
235  (((const uint8_t*)(x))[2] << 8) | \
236  ((const uint8_t*)(x))[3])
237 #endif
238 #ifndef AV_WB32
239 # define AV_WB32(p, d) do { \
240  ((uint8_t*)(p))[3] = (d); \
241  ((uint8_t*)(p))[2] = (d)>>8; \
242  ((uint8_t*)(p))[1] = (d)>>16; \
243  ((uint8_t*)(p))[0] = (d)>>24; \
244  } while(0)
245 #endif
246 
247 #ifndef AV_RL32
248 # define AV_RL32(x) \
249  (((uint32_t)((const uint8_t*)(x))[3] << 24) | \
250  (((const uint8_t*)(x))[2] << 16) | \
251  (((const uint8_t*)(x))[1] << 8) | \
252  ((const uint8_t*)(x))[0])
253 #endif
254 #ifndef AV_WL32
255 # define AV_WL32(p, d) do { \
256  ((uint8_t*)(p))[0] = (d); \
257  ((uint8_t*)(p))[1] = (d)>>8; \
258  ((uint8_t*)(p))[2] = (d)>>16; \
259  ((uint8_t*)(p))[3] = (d)>>24; \
260  } while(0)
261 #endif
262 
263 #ifndef AV_RB64
264 # define AV_RB64(x) \
265  (((uint64_t)((const uint8_t*)(x))[0] << 56) | \
266  ((uint64_t)((const uint8_t*)(x))[1] << 48) | \
267  ((uint64_t)((const uint8_t*)(x))[2] << 40) | \
268  ((uint64_t)((const uint8_t*)(x))[3] << 32) | \
269  ((uint64_t)((const uint8_t*)(x))[4] << 24) | \
270  ((uint64_t)((const uint8_t*)(x))[5] << 16) | \
271  ((uint64_t)((const uint8_t*)(x))[6] << 8) | \
272  (uint64_t)((const uint8_t*)(x))[7])
273 #endif
274 #ifndef AV_WB64
275 # define AV_WB64(p, d) do { \
276  ((uint8_t*)(p))[7] = (d); \
277  ((uint8_t*)(p))[6] = (d)>>8; \
278  ((uint8_t*)(p))[5] = (d)>>16; \
279  ((uint8_t*)(p))[4] = (d)>>24; \
280  ((uint8_t*)(p))[3] = (d)>>32; \
281  ((uint8_t*)(p))[2] = (d)>>40; \
282  ((uint8_t*)(p))[1] = (d)>>48; \
283  ((uint8_t*)(p))[0] = (d)>>56; \
284  } while(0)
285 #endif
286 
287 #ifndef AV_RL64
288 # define AV_RL64(x) \
289  (((uint64_t)((const uint8_t*)(x))[7] << 56) | \
290  ((uint64_t)((const uint8_t*)(x))[6] << 48) | \
291  ((uint64_t)((const uint8_t*)(x))[5] << 40) | \
292  ((uint64_t)((const uint8_t*)(x))[4] << 32) | \
293  ((uint64_t)((const uint8_t*)(x))[3] << 24) | \
294  ((uint64_t)((const uint8_t*)(x))[2] << 16) | \
295  ((uint64_t)((const uint8_t*)(x))[1] << 8) | \
296  (uint64_t)((const uint8_t*)(x))[0])
297 #endif
298 #ifndef AV_WL64
299 # define AV_WL64(p, d) do { \
300  ((uint8_t*)(p))[0] = (d); \
301  ((uint8_t*)(p))[1] = (d)>>8; \
302  ((uint8_t*)(p))[2] = (d)>>16; \
303  ((uint8_t*)(p))[3] = (d)>>24; \
304  ((uint8_t*)(p))[4] = (d)>>32; \
305  ((uint8_t*)(p))[5] = (d)>>40; \
306  ((uint8_t*)(p))[6] = (d)>>48; \
307  ((uint8_t*)(p))[7] = (d)>>56; \
308  } while(0)
309 #endif
310 
311 #if AV_HAVE_BIGENDIAN
312 # define AV_RN(s, p) AV_RB##s(p)
313 # define AV_WN(s, p, v) AV_WB##s(p, v)
314 #else
315 # define AV_RN(s, p) AV_RL##s(p)
316 # define AV_WN(s, p, v) AV_WL##s(p, v)
317 #endif
318 
319 #endif /* HAVE_FAST_UNALIGNED */
320 
321 #ifndef AV_RN16
322 # define AV_RN16(p) AV_RN(16, p)
323 #endif
324 
325 #ifndef AV_RN32
326 # define AV_RN32(p) AV_RN(32, p)
327 #endif
328 
329 #ifndef AV_RN64
330 # define AV_RN64(p) AV_RN(64, p)
331 #endif
332 
333 #ifndef AV_WN16
334 # define AV_WN16(p, v) AV_WN(16, p, v)
335 #endif
336 
337 #ifndef AV_WN32
338 # define AV_WN32(p, v) AV_WN(32, p, v)
339 #endif
340 
341 #ifndef AV_WN64
342 # define AV_WN64(p, v) AV_WN(64, p, v)
343 #endif
344 
345 #if AV_HAVE_BIGENDIAN
346 # define AV_RB(s, p) AV_RN##s(p)
347 # define AV_WB(s, p, v) AV_WN##s(p, v)
348 # define AV_RL(s, p) av_bswap##s(AV_RN##s(p))
349 # define AV_WL(s, p, v) AV_WN##s(p, av_bswap##s(v))
350 #else
351 # define AV_RB(s, p) av_bswap##s(AV_RN##s(p))
352 # define AV_WB(s, p, v) AV_WN##s(p, av_bswap##s(v))
353 # define AV_RL(s, p) AV_RN##s(p)
354 # define AV_WL(s, p, v) AV_WN##s(p, v)
355 #endif
356 
357 #define AV_RB8(x) (((const uint8_t*)(x))[0])
358 #define AV_WB8(p, d) do { ((uint8_t*)(p))[0] = (d); } while(0)
359 
360 #define AV_RL8(x) AV_RB8(x)
361 #define AV_WL8(p, d) AV_WB8(p, d)
362 
363 #ifndef AV_RB16
364 # define AV_RB16(p) AV_RB(16, p)
365 #endif
366 #ifndef AV_WB16
367 # define AV_WB16(p, v) AV_WB(16, p, v)
368 #endif
369 
370 #ifndef AV_RL16
371 # define AV_RL16(p) AV_RL(16, p)
372 #endif
373 #ifndef AV_WL16
374 # define AV_WL16(p, v) AV_WL(16, p, v)
375 #endif
376 
377 #ifndef AV_RB32
378 # define AV_RB32(p) AV_RB(32, p)
379 #endif
380 #ifndef AV_WB32
381 # define AV_WB32(p, v) AV_WB(32, p, v)
382 #endif
383 
384 #ifndef AV_RL32
385 # define AV_RL32(p) AV_RL(32, p)
386 #endif
387 #ifndef AV_WL32
388 # define AV_WL32(p, v) AV_WL(32, p, v)
389 #endif
390 
391 #ifndef AV_RB64
392 # define AV_RB64(p) AV_RB(64, p)
393 #endif
394 #ifndef AV_WB64
395 # define AV_WB64(p, v) AV_WB(64, p, v)
396 #endif
397 
398 #ifndef AV_RL64
399 # define AV_RL64(p) AV_RL(64, p)
400 #endif
401 #ifndef AV_WL64
402 # define AV_WL64(p, v) AV_WL(64, p, v)
403 #endif
404 
405 #ifndef AV_RB24
406 # define AV_RB24(x) \
407  ((((const uint8_t*)(x))[0] << 16) | \
408  (((const uint8_t*)(x))[1] << 8) | \
409  ((const uint8_t*)(x))[2])
410 #endif
411 #ifndef AV_WB24
412 # define AV_WB24(p, d) do { \
413  ((uint8_t*)(p))[2] = (d); \
414  ((uint8_t*)(p))[1] = (d)>>8; \
415  ((uint8_t*)(p))[0] = (d)>>16; \
416  } while(0)
417 #endif
418 
419 #ifndef AV_RL24
420 # define AV_RL24(x) \
421  ((((const uint8_t*)(x))[2] << 16) | \
422  (((const uint8_t*)(x))[1] << 8) | \
423  ((const uint8_t*)(x))[0])
424 #endif
425 #ifndef AV_WL24
426 # define AV_WL24(p, d) do { \
427  ((uint8_t*)(p))[0] = (d); \
428  ((uint8_t*)(p))[1] = (d)>>8; \
429  ((uint8_t*)(p))[2] = (d)>>16; \
430  } while(0)
431 #endif
432 
433 /*
434  * The AV_[RW]NA macros access naturally aligned data
435  * in a type-safe way.
436  */
437 
438 #define AV_RNA(s, p) (((const av_alias##s*)(p))->u##s)
439 #define AV_WNA(s, p, v) (((av_alias##s*)(p))->u##s = (v))
440 
441 #ifndef AV_RN16A
442 # define AV_RN16A(p) AV_RNA(16, p)
443 #endif
444 
445 #ifndef AV_RN32A
446 # define AV_RN32A(p) AV_RNA(32, p)
447 #endif
448 
449 #ifndef AV_RN64A
450 # define AV_RN64A(p) AV_RNA(64, p)
451 #endif
452 
453 #ifndef AV_WN16A
454 # define AV_WN16A(p, v) AV_WNA(16, p, v)
455 #endif
456 
457 #ifndef AV_WN32A
458 # define AV_WN32A(p, v) AV_WNA(32, p, v)
459 #endif
460 
461 #ifndef AV_WN64A
462 # define AV_WN64A(p, v) AV_WNA(64, p, v)
463 #endif
464 
465 /* Parameters for AV_COPY*, AV_SWAP*, AV_ZERO* must be
466  * naturally aligned. They may be implemented using MMX,
467  * so emms_c() must be called before using any float code
468  * afterwards.
469  */
470 
471 #define AV_COPY(n, d, s) \
472  (((av_alias##n*)(d))->u##n = ((const av_alias##n*)(s))->u##n)
473 
474 #ifndef AV_COPY16
475 # define AV_COPY16(d, s) AV_COPY(16, d, s)
476 #endif
477 
478 #ifndef AV_COPY32
479 # define AV_COPY32(d, s) AV_COPY(32, d, s)
480 #endif
481 
482 #ifndef AV_COPY64
483 # define AV_COPY64(d, s) AV_COPY(64, d, s)
484 #endif
485 
486 #ifndef AV_COPY128
487 # define AV_COPY128(d, s) \
488  do { \
489  AV_COPY64(d, s); \
490  AV_COPY64((char*)(d)+8, (char*)(s)+8); \
491  } while(0)
492 #endif
493 
494 #define AV_SWAP(n, a, b) FFSWAP(av_alias##n, *(av_alias##n*)(a), *(av_alias##n*)(b))
495 
496 #ifndef AV_SWAP64
497 # define AV_SWAP64(a, b) AV_SWAP(64, a, b)
498 #endif
499 
500 #define AV_ZERO(n, d) (((av_alias##n*)(d))->u##n = 0)
501 
502 #ifndef AV_ZERO16
503 # define AV_ZERO16(d) AV_ZERO(16, d)
504 #endif
505 
506 #ifndef AV_ZERO32
507 # define AV_ZERO32(d) AV_ZERO(32, d)
508 #endif
509 
510 #ifndef AV_ZERO64
511 # define AV_ZERO64(d) AV_ZERO(64, d)
512 #endif
513 
514 #ifndef AV_ZERO128
515 # define AV_ZERO128(d) \
516  do { \
517  AV_ZERO64(d); \
518  AV_ZERO64((char*)(d)+8); \
519  } while(0)
520 #endif
521 
522 #endif /* AVUTIL_INTREADWRITE_H */