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
21 /**
22 * @file
23 * common internal and external API header
24 */
25
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
86 /**
87 * Clip a signed integer value into the amin-amax range.
88 * @param a value to clip
89 * @param amin minimum value of the clip range
90 * @param amax maximum value of the clip range
91 * @return clipped value
92 */
av_clip_c(int a,int amin,int amax)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
100 /**
101 * Clip a signed integer value into the 0-255 range.
102 * @param a value to clip
103 * @return clipped value
104 */
av_clip_uint8_c(int a)105 static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
106 {
107 if (a&(~0xFF)) return (-a)>>31;
108 else return a;
109 }
110
111 /**
112 * Clip a signed integer value into the -128,127 range.
113 * @param a value to clip
114 * @return clipped value
115 */
av_clip_int8_c(int a)116 static av_always_inline av_const int8_t av_clip_int8_c(int a)
117 {
118 if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F;
119 else return a;
120 }
121
122 /**
123 * Clip a signed integer value into the 0-65535 range.
124 * @param a value to clip
125 * @return clipped value
126 */
av_clip_uint16_c(int a)127 static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
128 {
129 if (a&(~0xFFFF)) return (-a)>>31;
130 else return a;
131 }
132
133 /**
134 * Clip a signed integer value into the -32768,32767 range.
135 * @param a value to clip
136 * @return clipped value
137 */
av_clip_int16_c(int a)138 static av_always_inline av_const int16_t av_clip_int16_c(int a)
139 {
140 if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
141 else return a;
142 }
143
144 /**
145 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
146 * @param a value to clip
147 * @return clipped value
148 */
av_clipl_int32_c(int64_t a)149 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
150 {
151 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF;
152 else return a;
153 }
154
155 /**
156 * Clip a signed integer to an unsigned power of two range.
157 * @param a value to clip
158 * @param p bit position to clip at
159 * @return clipped value
160 */
av_clip_uintp2_c(int a,int p)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
167 /**
168 * Add two signed 32-bit values with saturation.
169 *
170 * @param a one value
171 * @param b another value
172 * @return sum with signed saturation
173 */
av_sat_add32_c(int a,int b)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
179 /**
180 * Add a doubled value to another value with saturation at both stages.
181 *
182 * @param a first value
183 * @param b value doubled and added to a
184 * @return sum with signed saturation
185 */
av_sat_dadd32_c(int a,int b)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
191 /**
192 * Clip a float value into the amin-amax range.
193 * @param a value to clip
194 * @param amin minimum value of the clip range
195 * @param amax maximum value of the clip range
196 * @return clipped value
197 */
av_clipf_c(float a,float amin,float amax)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
205 /** Compute ceil(log2(x)).
206 * @param x value used to compute ceil(log2(x))
207 * @return computed ceiling of log2(x)
208 */
av_ceil_log2_c(int x)209 static av_always_inline av_const int av_ceil_log2_c(int x)
210 {
211 return av_log2((x - 1) << 1);
212 }
213
214 /**
215 * Count number of bits set to one in x
216 * @param x value to count bits of
217 * @return the number of bits set to one in x
218 */
av_popcount_c(uint32_t x)219 static av_always_inline av_const int av_popcount_c(uint32_t x)
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
228 /**
229 * Count number of bits set to one in x
230 * @param x value to count bits of
231 * @return the number of bits set to one in x
232 */
av_popcount64_c(uint64_t x)233 static av_always_inline av_const int av_popcount64_c(uint64_t x)
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
241 /**
242 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
243 *
244 * @param val Output value, must be an lvalue of type uint32_t.
245 * @param GET_BYTE Expression reading one byte from the input.
246 * Evaluated up to 7 times (4 for the currently
247 * assigned Unicode range). With a memory buffer
248 * input, this could be *ptr++.
249 * @param ERROR Expression to be evaluated on invalid input,
250 * typically a goto statement.
251 */
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
268 /**
269 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
270 *
271 * @param val Output value, must be an lvalue of type uint32_t.
272 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
273 * to native byte order. Evaluated one or two times.
274 * @param ERROR Expression to be evaluated on invalid input,
275 * typically a goto statement.
276 */
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 /**
290 * @def PUT_UTF8(val, tmp, PUT_BYTE)
291 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
292 * @param val is an input-only argument and should be of type uint32_t. It holds
293 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
294 * val is given as a function it is executed only once.
295 * @param tmp is a temporary variable and should be of type uint8_t. It
296 * represents an intermediate value during conversion that is to be
297 * output by PUT_BYTE.
298 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
299 * It could be a function or a statement, and uses tmp as the input byte.
300 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
301 * executed up to 4 times for values in the valid UTF-8 range and up to
302 * 7 times in the general case, depending on the length of the converted
303 * Unicode character.
304 */
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
325 /**
326 * @def PUT_UTF16(val, tmp, PUT_16BIT)
327 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
328 * @param val is an input-only argument and should be of type uint32_t. It holds
329 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
330 * val is given as a function it is executed only once.
331 * @param tmp is a temporary variable and should be of type uint16_t. It
332 * represents an intermediate value during conversion that is to be
333 * output by PUT_16BIT.
334 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
335 * in desired endianness. It could be a function or a statement, and uses tmp
336 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
337 * PUT_BYTE will be executed 1 or 2 times depending on input character.
338 */
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
407