Libav
common.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
26 #ifndef AVUTIL_COMMON_H
27 #define AVUTIL_COMMON_H
28 
29 #include <errno.h>
30 #include <inttypes.h>
31 #include <limits.h>
32 #include <math.h>
33 #include <stdint.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 
38 #include "attributes.h"
39 #include "version.h"
40 #include "libavutil/avconfig.h"
41 
42 #if AV_HAVE_BIGENDIAN
43 # define AV_NE(be, le) (be)
44 #else
45 # define AV_NE(be, le) (le)
46 #endif
47 
48 //rounded division & shift
49 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
50 /* assume b>0 */
51 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
52 #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
53 #define FFSIGN(a) ((a) > 0 ? 1 : -1)
54 
55 #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
56 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
57 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
58 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
59 
60 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
61 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
62 #define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1))
63 
64 /* misc math functions */
65 
66 #if FF_API_AV_REVERSE
67 extern attribute_deprecated const uint8_t av_reverse[256];
68 #endif
69 
70 #ifdef HAVE_AV_CONFIG_H
71 # include "config.h"
72 # include "intmath.h"
73 #endif
74 
75 /* Pull in unguarded fallback defines at the end of this file. */
76 #include "common.h"
77 
78 #ifndef av_log2
79 av_const int av_log2(unsigned v);
80 #endif
81 
82 #ifndef av_log2_16bit
83 av_const int av_log2_16bit(unsigned v);
84 #endif
85 
93 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
94 {
95  if (a < amin) return amin;
96  else if (a > amax) return amax;
97  else return a;
98 }
99 
106 {
107  if (a&(~0xFF)) return (-a)>>31;
108  else return a;
109 }
110 
117 {
118  if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F;
119  else return a;
120 }
121 
128 {
129  if (a&(~0xFFFF)) return (-a)>>31;
130  else return a;
131 }
132 
139 {
140  if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
141  else return a;
142 }
143 
150 {
151  if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF;
152  else return a;
153 }
154 
161 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
162 {
163  if (a & ~((1<<p) - 1)) return -a >> 31 & ((1<<p) - 1);
164  else return a;
165 }
166 
174 static av_always_inline int av_sat_add32_c(int a, int b)
175 {
176  return av_clipl_int32((int64_t)a + b);
177 }
178 
186 static av_always_inline int av_sat_dadd32_c(int a, int b)
187 {
188  return av_sat_add32(a, av_sat_add32(b, b));
189 }
190 
198 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
199 {
200  if (a < amin) return amin;
201  else if (a > amax) return amax;
202  else return a;
203 }
204 
210 {
211  return av_log2((x - 1) << 1);
212 }
213 
220 {
221  x -= (x >> 1) & 0x55555555;
222  x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
223  x = (x + (x >> 4)) & 0x0F0F0F0F;
224  x += x >> 8;
225  return (x + (x >> 16)) & 0x3F;
226 }
227 
234 {
235  return av_popcount(x) + av_popcount(x >> 32);
236 }
237 
238 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
239 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
240 
252 #define GET_UTF8(val, GET_BYTE, ERROR)\
253  val= GET_BYTE;\
254  {\
255  uint32_t top = (val & 128) >> 1;\
256  if ((val & 0xc0) == 0x80)\
257  ERROR\
258  while (val & top) {\
259  int tmp= GET_BYTE - 128;\
260  if(tmp>>6)\
261  ERROR\
262  val= (val<<6) + tmp;\
263  top <<= 5;\
264  }\
265  val &= (top << 1) - 1;\
266  }
267 
277 #define GET_UTF16(val, GET_16BIT, ERROR)\
278  val = GET_16BIT;\
279  {\
280  unsigned int hi = val - 0xD800;\
281  if (hi < 0x800) {\
282  val = GET_16BIT - 0xDC00;\
283  if (val > 0x3FFU || hi > 0x3FFU)\
284  ERROR\
285  val += (hi<<10) + 0x10000;\
286  }\
287  }\
288 
289 
305 #define PUT_UTF8(val, tmp, PUT_BYTE)\
306  {\
307  int bytes, shift;\
308  uint32_t in = val;\
309  if (in < 0x80) {\
310  tmp = in;\
311  PUT_BYTE\
312  } else {\
313  bytes = (av_log2(in) + 4) / 5;\
314  shift = (bytes - 1) * 6;\
315  tmp = (256 - (256 >> bytes)) | (in >> shift);\
316  PUT_BYTE\
317  while (shift >= 6) {\
318  shift -= 6;\
319  tmp = 0x80 | ((in >> shift) & 0x3f);\
320  PUT_BYTE\
321  }\
322  }\
323  }
324 
339 #define PUT_UTF16(val, tmp, PUT_16BIT)\
340  {\
341  uint32_t in = val;\
342  if (in < 0x10000) {\
343  tmp = in;\
344  PUT_16BIT\
345  } else {\
346  tmp = 0xD800 | ((in - 0x10000) >> 10);\
347  PUT_16BIT\
348  tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
349  PUT_16BIT\
350  }\
351  }\
352 
353 
354 
355 #include "mem.h"
356 
357 #ifdef HAVE_AV_CONFIG_H
358 # include "internal.h"
359 #endif /* HAVE_AV_CONFIG_H */
360 
361 #endif /* AVUTIL_COMMON_H */
362 
363 /*
364  * The following definitions are outside the multiple inclusion guard
365  * to ensure they are immediately available in intmath.h.
366  */
367 
368 #ifndef av_ceil_log2
369 # define av_ceil_log2 av_ceil_log2_c
370 #endif
371 #ifndef av_clip
372 # define av_clip av_clip_c
373 #endif
374 #ifndef av_clip_uint8
375 # define av_clip_uint8 av_clip_uint8_c
376 #endif
377 #ifndef av_clip_int8
378 # define av_clip_int8 av_clip_int8_c
379 #endif
380 #ifndef av_clip_uint16
381 # define av_clip_uint16 av_clip_uint16_c
382 #endif
383 #ifndef av_clip_int16
384 # define av_clip_int16 av_clip_int16_c
385 #endif
386 #ifndef av_clipl_int32
387 # define av_clipl_int32 av_clipl_int32_c
388 #endif
389 #ifndef av_clip_uintp2
390 # define av_clip_uintp2 av_clip_uintp2_c
391 #endif
392 #ifndef av_sat_add32
393 # define av_sat_add32 av_sat_add32_c
394 #endif
395 #ifndef av_sat_dadd32
396 # define av_sat_dadd32 av_sat_dadd32_c
397 #endif
398 #ifndef av_clipf
399 # define av_clipf av_clipf_c
400 #endif
401 #ifndef av_popcount
402 # define av_popcount av_popcount_c
403 #endif
404 #ifndef av_popcount64
405 # define av_popcount64 av_popcount64_c
406 #endif
#define av_const
Definition: attributes.h:60
static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
Definition: common.h:149
static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
Clip a float value into the amin-amax range.
Definition: common.h:198
memory handling functions
static av_always_inline av_const int8_t av_clip_int8_c(int a)
Clip a signed integer value into the -128,127 range.
Definition: common.h:116
av_const int av_log2_16bit(unsigned v)
Definition: intmath.c:31
Macro definitions for various function/variable attributes.
uint8_t
#define b
Definition: input.c:52
static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
Clip a signed integer value into the amin-amax range.
Definition: common.h:93
Libavutil version macros.
static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
Clip a signed integer value into the 0-65535 range.
Definition: common.h:127
static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
Clip a signed integer value into the 0-255 range.
Definition: common.h:105
int32_t
av_const int av_log2(unsigned v)
Definition: intmath.c:26
attribute_deprecated const uint8_t av_reverse[256]
Definition: mathematics.c:33
static av_always_inline av_const int16_t av_clip_int16_c(int a)
Clip a signed integer value into the -32768,32767 range.
Definition: common.h:138
#define attribute_deprecated
Definition: attributes.h:80
common internal and external API header
static av_always_inline av_const int av_popcount_c(uint32_t x)
Count number of bits set to one in x.
Definition: common.h:219
static av_always_inline int av_sat_add32_c(int a, int b)
Add two signed 32-bit values with saturation.
Definition: common.h:174
static av_always_inline av_const int av_popcount64_c(uint64_t x)
Count number of bits set to one in x.
Definition: common.h:233
static av_always_inline int av_sat_dadd32_c(int a, int b)
Add a doubled value to another value with saturation at both stages.
Definition: common.h:186
#define av_always_inline
Definition: attributes.h:40
static av_always_inline av_const int av_ceil_log2_c(int x)
Compute ceil(log2(x)).
Definition: common.h:209
static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
Clip a signed integer to an unsigned power of two range.
Definition: common.h:161