Libav
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 defined(_MSC_VER) && (defined(_M_ARM) || defined(_M_X64)) && AV_HAVE_FAST_UNALIGNED
201 
202 # define AV_RN(s, p) (*((const __unaligned uint##s##_t*)(p)))
203 # define AV_WN(s, p, v) (*((__unaligned uint##s##_t*)(p)) = (v))
204 
205 #elif AV_HAVE_FAST_UNALIGNED
206 
207 # define AV_RN(s, p) (((const av_alias##s*)(p))->u##s)
208 # define AV_WN(s, p, v) (((av_alias##s*)(p))->u##s = (v))
209 
210 #else
211 
212 #ifndef AV_RB16
213 # define AV_RB16(x) \
214  ((((const uint8_t*)(x))[0] << 8) | \
215  ((const uint8_t*)(x))[1])
216 #endif
217 #ifndef AV_WB16
218 # define AV_WB16(p, val) do { \
219  uint16_t d = val; \
220  ((uint8_t*)(p))[1] = (d); \
221  ((uint8_t*)(p))[0] = (d)>>8; \
222  } while(0)
223 #endif
224 
225 #ifndef AV_RL16
226 # define AV_RL16(x) \
227  ((((const uint8_t*)(x))[1] << 8) | \
228  ((const uint8_t*)(x))[0])
229 #endif
230 #ifndef AV_WL16
231 # define AV_WL16(p, val) do { \
232  uint16_t d = val; \
233  ((uint8_t*)(p))[0] = (d); \
234  ((uint8_t*)(p))[1] = (d)>>8; \
235  } while(0)
236 #endif
237 
238 #ifndef AV_RB32
239 # define AV_RB32(x) \
240  (((uint32_t)((const uint8_t*)(x))[0] << 24) | \
241  (((const uint8_t*)(x))[1] << 16) | \
242  (((const uint8_t*)(x))[2] << 8) | \
243  ((const uint8_t*)(x))[3])
244 #endif
245 #ifndef AV_WB32
246 # define AV_WB32(p, val) do { \
247  uint32_t d = val; \
248  ((uint8_t*)(p))[3] = (d); \
249  ((uint8_t*)(p))[2] = (d)>>8; \
250  ((uint8_t*)(p))[1] = (d)>>16; \
251  ((uint8_t*)(p))[0] = (d)>>24; \
252  } while(0)
253 #endif
254 
255 #ifndef AV_RL32
256 # define AV_RL32(x) \
257  (((uint32_t)((const uint8_t*)(x))[3] << 24) | \
258  (((const uint8_t*)(x))[2] << 16) | \
259  (((const uint8_t*)(x))[1] << 8) | \
260  ((const uint8_t*)(x))[0])
261 #endif
262 #ifndef AV_WL32
263 # define AV_WL32(p, val) do { \
264  uint32_t d = val; \
265  ((uint8_t*)(p))[0] = (d); \
266  ((uint8_t*)(p))[1] = (d)>>8; \
267  ((uint8_t*)(p))[2] = (d)>>16; \
268  ((uint8_t*)(p))[3] = (d)>>24; \
269  } while(0)
270 #endif
271 
272 #ifndef AV_RB64
273 # define AV_RB64(x) \
274  (((uint64_t)((const uint8_t*)(x))[0] << 56) | \
275  ((uint64_t)((const uint8_t*)(x))[1] << 48) | \
276  ((uint64_t)((const uint8_t*)(x))[2] << 40) | \
277  ((uint64_t)((const uint8_t*)(x))[3] << 32) | \
278  ((uint64_t)((const uint8_t*)(x))[4] << 24) | \
279  ((uint64_t)((const uint8_t*)(x))[5] << 16) | \
280  ((uint64_t)((const uint8_t*)(x))[6] << 8) | \
281  (uint64_t)((const uint8_t*)(x))[7])
282 #endif
283 #ifndef AV_WB64
284 # define AV_WB64(p, val) do { \
285  uint64_t d = val; \
286  ((uint8_t*)(p))[7] = (d); \
287  ((uint8_t*)(p))[6] = (d)>>8; \
288  ((uint8_t*)(p))[5] = (d)>>16; \
289  ((uint8_t*)(p))[4] = (d)>>24; \
290  ((uint8_t*)(p))[3] = (d)>>32; \
291  ((uint8_t*)(p))[2] = (d)>>40; \
292  ((uint8_t*)(p))[1] = (d)>>48; \
293  ((uint8_t*)(p))[0] = (d)>>56; \
294  } while(0)
295 #endif
296 
297 #ifndef AV_RL64
298 # define AV_RL64(x) \
299  (((uint64_t)((const uint8_t*)(x))[7] << 56) | \
300  ((uint64_t)((const uint8_t*)(x))[6] << 48) | \
301  ((uint64_t)((const uint8_t*)(x))[5] << 40) | \
302  ((uint64_t)((const uint8_t*)(x))[4] << 32) | \
303  ((uint64_t)((const uint8_t*)(x))[3] << 24) | \
304  ((uint64_t)((const uint8_t*)(x))[2] << 16) | \
305  ((uint64_t)((const uint8_t*)(x))[1] << 8) | \
306  (uint64_t)((const uint8_t*)(x))[0])
307 #endif
308 #ifndef AV_WL64
309 # define AV_WL64(p, val) do { \
310  uint64_t d = val; \
311  ((uint8_t*)(p))[0] = (d); \
312  ((uint8_t*)(p))[1] = (d)>>8; \
313  ((uint8_t*)(p))[2] = (d)>>16; \
314  ((uint8_t*)(p))[3] = (d)>>24; \
315  ((uint8_t*)(p))[4] = (d)>>32; \
316  ((uint8_t*)(p))[5] = (d)>>40; \
317  ((uint8_t*)(p))[6] = (d)>>48; \
318  ((uint8_t*)(p))[7] = (d)>>56; \
319  } while(0)
320 #endif
321 
322 #if AV_HAVE_BIGENDIAN
323 # define AV_RN(s, p) AV_RB##s(p)
324 # define AV_WN(s, p, v) AV_WB##s(p, v)
325 #else
326 # define AV_RN(s, p) AV_RL##s(p)
327 # define AV_WN(s, p, v) AV_WL##s(p, v)
328 #endif
329 
330 #endif /* HAVE_FAST_UNALIGNED */
331 
332 #ifndef AV_RN16
333 # define AV_RN16(p) AV_RN(16, p)
334 #endif
335 
336 #ifndef AV_RN32
337 # define AV_RN32(p) AV_RN(32, p)
338 #endif
339 
340 #ifndef AV_RN64
341 # define AV_RN64(p) AV_RN(64, p)
342 #endif
343 
344 #ifndef AV_WN16
345 # define AV_WN16(p, v) AV_WN(16, p, v)
346 #endif
347 
348 #ifndef AV_WN32
349 # define AV_WN32(p, v) AV_WN(32, p, v)
350 #endif
351 
352 #ifndef AV_WN64
353 # define AV_WN64(p, v) AV_WN(64, p, v)
354 #endif
355 
356 #if AV_HAVE_BIGENDIAN
357 # define AV_RB(s, p) AV_RN##s(p)
358 # define AV_WB(s, p, v) AV_WN##s(p, v)
359 # define AV_RL(s, p) av_bswap##s(AV_RN##s(p))
360 # define AV_WL(s, p, v) AV_WN##s(p, av_bswap##s(v))
361 #else
362 # define AV_RB(s, p) av_bswap##s(AV_RN##s(p))
363 # define AV_WB(s, p, v) AV_WN##s(p, av_bswap##s(v))
364 # define AV_RL(s, p) AV_RN##s(p)
365 # define AV_WL(s, p, v) AV_WN##s(p, v)
366 #endif
367 
368 #define AV_RB8(x) (((const uint8_t*)(x))[0])
369 #define AV_WB8(p, d) do { ((uint8_t*)(p))[0] = (d); } while(0)
370 
371 #define AV_RL8(x) AV_RB8(x)
372 #define AV_WL8(p, d) AV_WB8(p, d)
373 
374 #ifndef AV_RB16
375 # define AV_RB16(p) AV_RB(16, p)
376 #endif
377 #ifndef AV_WB16
378 # define AV_WB16(p, v) AV_WB(16, p, v)
379 #endif
380 
381 #ifndef AV_RL16
382 # define AV_RL16(p) AV_RL(16, p)
383 #endif
384 #ifndef AV_WL16
385 # define AV_WL16(p, v) AV_WL(16, p, v)
386 #endif
387 
388 #ifndef AV_RB32
389 # define AV_RB32(p) AV_RB(32, p)
390 #endif
391 #ifndef AV_WB32
392 # define AV_WB32(p, v) AV_WB(32, p, v)
393 #endif
394 
395 #ifndef AV_RL32
396 # define AV_RL32(p) AV_RL(32, p)
397 #endif
398 #ifndef AV_WL32
399 # define AV_WL32(p, v) AV_WL(32, p, v)
400 #endif
401 
402 #ifndef AV_RB64
403 # define AV_RB64(p) AV_RB(64, p)
404 #endif
405 #ifndef AV_WB64
406 # define AV_WB64(p, v) AV_WB(64, p, v)
407 #endif
408 
409 #ifndef AV_RL64
410 # define AV_RL64(p) AV_RL(64, p)
411 #endif
412 #ifndef AV_WL64
413 # define AV_WL64(p, v) AV_WL(64, p, v)
414 #endif
415 
416 #ifndef AV_RB24
417 # define AV_RB24(x) \
418  ((((const uint8_t*)(x))[0] << 16) | \
419  (((const uint8_t*)(x))[1] << 8) | \
420  ((const uint8_t*)(x))[2])
421 #endif
422 #ifndef AV_WB24
423 # define AV_WB24(p, d) do { \
424  ((uint8_t*)(p))[2] = (d); \
425  ((uint8_t*)(p))[1] = (d)>>8; \
426  ((uint8_t*)(p))[0] = (d)>>16; \
427  } while(0)
428 #endif
429 
430 #ifndef AV_RL24
431 # define AV_RL24(x) \
432  ((((const uint8_t*)(x))[2] << 16) | \
433  (((const uint8_t*)(x))[1] << 8) | \
434  ((const uint8_t*)(x))[0])
435 #endif
436 #ifndef AV_WL24
437 # define AV_WL24(p, d) do { \
438  ((uint8_t*)(p))[0] = (d); \
439  ((uint8_t*)(p))[1] = (d)>>8; \
440  ((uint8_t*)(p))[2] = (d)>>16; \
441  } while(0)
442 #endif
443 
444 /*
445  * The AV_[RW]NA macros access naturally aligned data
446  * in a type-safe way.
447  */
448 
449 #define AV_RNA(s, p) (((const av_alias##s*)(p))->u##s)
450 #define AV_WNA(s, p, v) (((av_alias##s*)(p))->u##s = (v))
451 
452 #ifndef AV_RN16A
453 # define AV_RN16A(p) AV_RNA(16, p)
454 #endif
455 
456 #ifndef AV_RN32A
457 # define AV_RN32A(p) AV_RNA(32, p)
458 #endif
459 
460 #ifndef AV_RN64A
461 # define AV_RN64A(p) AV_RNA(64, p)
462 #endif
463 
464 #ifndef AV_WN16A
465 # define AV_WN16A(p, v) AV_WNA(16, p, v)
466 #endif
467 
468 #ifndef AV_WN32A
469 # define AV_WN32A(p, v) AV_WNA(32, p, v)
470 #endif
471 
472 #ifndef AV_WN64A
473 # define AV_WN64A(p, v) AV_WNA(64, p, v)
474 #endif
475 
476 /*
477  * The AV_COPYxxU macros are suitable for copying data to/from unaligned
478  * memory locations.
479  */
480 
481 #define AV_COPYU(n, d, s) AV_WN##n(d, AV_RN##n(s));
482 
483 #ifndef AV_COPY16U
484 # define AV_COPY16U(d, s) AV_COPYU(16, d, s)
485 #endif
486 
487 #ifndef AV_COPY32U
488 # define AV_COPY32U(d, s) AV_COPYU(32, d, s)
489 #endif
490 
491 #ifndef AV_COPY64U
492 # define AV_COPY64U(d, s) AV_COPYU(64, d, s)
493 #endif
494 
495 #ifndef AV_COPY128U
496 # define AV_COPY128U(d, s) \
497  do { \
498  AV_COPY64U(d, s); \
499  AV_COPY64U((char *)(d) + 8, (const char *)(s) + 8); \
500  } while(0)
501 #endif
502 
503 /* Parameters for AV_COPY*, AV_SWAP*, AV_ZERO* must be
504  * naturally aligned. They may be implemented using MMX,
505  * so emms_c() must be called before using any float code
506  * afterwards.
507  */
508 
509 #define AV_COPY(n, d, s) \
510  (((av_alias##n*)(d))->u##n = ((const av_alias##n*)(s))->u##n)
511 
512 #ifndef AV_COPY16
513 # define AV_COPY16(d, s) AV_COPY(16, d, s)
514 #endif
515 
516 #ifndef AV_COPY32
517 # define AV_COPY32(d, s) AV_COPY(32, d, s)
518 #endif
519 
520 #ifndef AV_COPY64
521 # define AV_COPY64(d, s) AV_COPY(64, d, s)
522 #endif
523 
524 #ifndef AV_COPY128
525 # define AV_COPY128(d, s) \
526  do { \
527  AV_COPY64(d, s); \
528  AV_COPY64((char*)(d)+8, (char*)(s)+8); \
529  } while(0)
530 #endif
531 
532 #define AV_SWAP(n, a, b) FFSWAP(av_alias##n, *(av_alias##n*)(a), *(av_alias##n*)(b))
533 
534 #ifndef AV_SWAP64
535 # define AV_SWAP64(a, b) AV_SWAP(64, a, b)
536 #endif
537 
538 #define AV_ZERO(n, d) (((av_alias##n*)(d))->u##n = 0)
539 
540 #ifndef AV_ZERO16
541 # define AV_ZERO16(d) AV_ZERO(16, d)
542 #endif
543 
544 #ifndef AV_ZERO32
545 # define AV_ZERO32(d) AV_ZERO(32, d)
546 #endif
547 
548 #ifndef AV_ZERO64
549 # define AV_ZERO64(d) AV_ZERO(64, d)
550 #endif
551 
552 #ifndef AV_ZERO128
553 # define AV_ZERO128(d) \
554  do { \
555  AV_ZERO64(d); \
556  AV_ZERO64((char*)(d)+8); \
557  } while(0)
558 #endif
559 
560 #endif /* AVUTIL_INTREADWRITE_H */
Macro definitions for various function/variable attributes.
uint8_t
#define av_alias
Definition: attributes.h:103
uint64_t u64
Definition: intreadwrite.h:28
byte swapping routines
double f64
Definition: intreadwrite.h:32