1 /*
2 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
3 * Copyright (c) 2007 Mans Rullgard
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include <limits.h>
23 #include <stdarg.h>
24 #include <stdint.h>
25 #include <stdio.h>
26 #include <string.h>
27
28 #include "config.h"
29 #include "mem.h"
30 #include "avassert.h"
31 #include "avstring.h"
32 #include "bprint.h"
33 #include "error.h"
34 #include "macros.h"
35 #include "version.h"
36
av_strstart(const char * str,const char * pfx,const char ** ptr)37 int av_strstart(const char *str, const char *pfx, const char **ptr)
38 {
39 while (*pfx && *pfx == *str) {
40 pfx++;
41 str++;
42 }
43 if (!*pfx && ptr)
44 *ptr = str;
45 return !*pfx;
46 }
47
av_stristart(const char * str,const char * pfx,const char ** ptr)48 int av_stristart(const char *str, const char *pfx, const char **ptr)
49 {
50 while (*pfx && av_toupper((unsigned)*pfx) == av_toupper((unsigned)*str)) {
51 pfx++;
52 str++;
53 }
54 if (!*pfx && ptr)
55 *ptr = str;
56 return !*pfx;
57 }
58
av_stristr(const char * s1,const char * s2)59 char *av_stristr(const char *s1, const char *s2)
60 {
61 if (!*s2)
62 return (char*)(intptr_t)s1;
63
64 do
65 if (av_stristart(s1, s2, NULL))
66 return (char*)(intptr_t)s1;
67 while (*s1++);
68
69 return NULL;
70 }
71
av_strnstr(const char * haystack,const char * needle,size_t hay_length)72 char *av_strnstr(const char *haystack, const char *needle, size_t hay_length)
73 {
74 size_t needle_len = strlen(needle);
75 if (!needle_len)
76 return (char*)haystack;
77 while (hay_length >= needle_len) {
78 hay_length--;
79 if (!memcmp(haystack, needle, needle_len))
80 return (char*)haystack;
81 haystack++;
82 }
83 return NULL;
84 }
85
av_strlcpy(char * dst,const char * src,size_t size)86 size_t av_strlcpy(char *dst, const char *src, size_t size)
87 {
88 size_t len = 0;
89 while (++len < size && *src)
90 *dst++ = *src++;
91 if (len <= size)
92 *dst = 0;
93 return len + strlen(src) - 1;
94 }
95
av_strlcat(char * dst,const char * src,size_t size)96 size_t av_strlcat(char *dst, const char *src, size_t size)
97 {
98 size_t len = strlen(dst);
99 if (size <= len + 1)
100 return len + strlen(src);
101 return len + av_strlcpy(dst + len, src, size - len);
102 }
103
av_strlcatf(char * dst,size_t size,const char * fmt,...)104 size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...)
105 {
106 size_t len = strlen(dst);
107 va_list vl;
108
109 va_start(vl, fmt);
110 len += vsnprintf(dst + len, size > len ? size - len : 0, fmt, vl);
111 va_end(vl);
112
113 return len;
114 }
115
av_asprintf(const char * fmt,...)116 char *av_asprintf(const char *fmt, ...)
117 {
118 char *p = NULL;
119 va_list va;
120 int len;
121
122 va_start(va, fmt);
123 len = vsnprintf(NULL, 0, fmt, va);
124 va_end(va);
125 if (len < 0)
126 goto end;
127
128 p = av_malloc(len + 1);
129 if (!p)
130 goto end;
131
132 va_start(va, fmt);
133 len = vsnprintf(p, len + 1, fmt, va);
134 va_end(va);
135 if (len < 0)
136 av_freep(&p);
137
138 end:
139 return p;
140 }
141
142 #if FF_API_D2STR
av_d2str(double d)143 char *av_d2str(double d)
144 {
145 char *str = av_malloc(16);
146 if (str)
147 snprintf(str, 16, "%f", d);
148 return str;
149 }
150 #endif
151
152 #define WHITESPACES " \n\t\r"
153
av_get_token(const char ** buf,const char * term)154 char *av_get_token(const char **buf, const char *term)
155 {
156 char *out = av_malloc(strlen(*buf) + 1);
157 char *ret = out, *end = out;
158 const char *p = *buf;
159 if (!out)
160 return NULL;
161 p += strspn(p, WHITESPACES);
162
163 while (*p && !strspn(p, term)) {
164 char c = *p++;
165 if (c == '\\' && *p) {
166 *out++ = *p++;
167 end = out;
168 } else if (c == '\'') {
169 while (*p && *p != '\'')
170 *out++ = *p++;
171 if (*p) {
172 p++;
173 end = out;
174 }
175 } else {
176 *out++ = c;
177 }
178 }
179
180 do
181 *out-- = 0;
182 while (out >= end && strspn(out, WHITESPACES));
183
184 *buf = p;
185
186 return ret;
187 }
188
av_strtok(char * s,const char * delim,char ** saveptr)189 char *av_strtok(char *s, const char *delim, char **saveptr)
190 {
191 char *tok;
192
193 if (!s && !(s = *saveptr))
194 return NULL;
195
196 /* skip leading delimiters */
197 s += strspn(s, delim);
198
199 /* s now points to the first non delimiter char, or to the end of the string */
200 if (!*s) {
201 *saveptr = NULL;
202 return NULL;
203 }
204 tok = s++;
205
206 /* skip non delimiters */
207 s += strcspn(s, delim);
208 if (*s) {
209 *s = 0;
210 *saveptr = s+1;
211 } else {
212 *saveptr = NULL;
213 }
214
215 return tok;
216 }
217
av_strcasecmp(const char * a,const char * b)218 int av_strcasecmp(const char *a, const char *b)
219 {
220 uint8_t c1, c2;
221 do {
222 c1 = av_tolower(*a++);
223 c2 = av_tolower(*b++);
224 } while (c1 && c1 == c2);
225 return c1 - c2;
226 }
227
av_strncasecmp(const char * a,const char * b,size_t n)228 int av_strncasecmp(const char *a, const char *b, size_t n)
229 {
230 uint8_t c1, c2;
231 if (n <= 0)
232 return 0;
233 do {
234 c1 = av_tolower(*a++);
235 c2 = av_tolower(*b++);
236 } while (--n && c1 && c1 == c2);
237 return c1 - c2;
238 }
239
av_strireplace(const char * str,const char * from,const char * to)240 char *av_strireplace(const char *str, const char *from, const char *to)
241 {
242 char *ret = NULL;
243 const char *pstr2, *pstr = str;
244 size_t tolen = strlen(to), fromlen = strlen(from);
245 AVBPrint pbuf;
246
247 av_bprint_init(&pbuf, 1, AV_BPRINT_SIZE_UNLIMITED);
248 while ((pstr2 = av_stristr(pstr, from))) {
249 av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);
250 pstr = pstr2 + fromlen;
251 av_bprint_append_data(&pbuf, to, tolen);
252 }
253 av_bprint_append_data(&pbuf, pstr, strlen(pstr));
254 if (!av_bprint_is_complete(&pbuf)) {
255 av_bprint_finalize(&pbuf, NULL);
256 } else {
257 av_bprint_finalize(&pbuf, &ret);
258 }
259
260 return ret;
261 }
262
av_basename(const char * path)263 const char *av_basename(const char *path)
264 {
265 char *p;
266 #if HAVE_DOS_PATHS
267 char *q, *d;
268 #endif
269
270 if (!path || *path == '\0')
271 return ".";
272
273 p = strrchr(path, '/');
274 #if HAVE_DOS_PATHS
275 q = strrchr(path, '\\');
276 d = strchr(path, ':');
277 p = FFMAX3(p, q, d);
278 #endif
279
280 if (!p)
281 return path;
282
283 return p + 1;
284 }
285
av_dirname(char * path)286 const char *av_dirname(char *path)
287 {
288 char *p = path ? strrchr(path, '/') : NULL;
289
290 #if HAVE_DOS_PATHS
291 char *q = path ? strrchr(path, '\\') : NULL;
292 char *d = path ? strchr(path, ':') : NULL;
293
294 d = d ? d + 1 : d;
295
296 p = FFMAX3(p, q, d);
297 #endif
298
299 if (!p)
300 return ".";
301
302 *p = '\0';
303
304 return path;
305 }
306
av_append_path_component(const char * path,const char * component)307 char *av_append_path_component(const char *path, const char *component)
308 {
309 size_t p_len, c_len;
310 char *fullpath;
311
312 if (!path)
313 return av_strdup(component);
314 if (!component)
315 return av_strdup(path);
316
317 p_len = strlen(path);
318 c_len = strlen(component);
319 if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)
320 return NULL;
321 fullpath = av_malloc(p_len + c_len + 2);
322 if (fullpath) {
323 if (p_len) {
324 av_strlcpy(fullpath, path, p_len + 1);
325 if (c_len) {
326 if (fullpath[p_len - 1] != '/' && component[0] != '/')
327 fullpath[p_len++] = '/';
328 else if (fullpath[p_len - 1] == '/' && component[0] == '/')
329 p_len--;
330 }
331 }
332 av_strlcpy(&fullpath[p_len], component, c_len + 1);
333 fullpath[p_len + c_len] = 0;
334 }
335 return fullpath;
336 }
337
av_escape(char ** dst,const char * src,const char * special_chars,enum AVEscapeMode mode,int flags)338 int av_escape(char **dst, const char *src, const char *special_chars,
339 enum AVEscapeMode mode, int flags)
340 {
341 AVBPrint dstbuf;
342 int ret;
343
344 av_bprint_init(&dstbuf, 1, INT_MAX); /* (int)dstbuf.len must be >= 0 */
345 av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
346
347 if (!av_bprint_is_complete(&dstbuf)) {
348 av_bprint_finalize(&dstbuf, NULL);
349 return AVERROR(ENOMEM);
350 }
351 if ((ret = av_bprint_finalize(&dstbuf, dst)) < 0)
352 return ret;
353 return dstbuf.len;
354 }
355
av_match_name(const char * name,const char * names)356 int av_match_name(const char *name, const char *names)
357 {
358 const char *p;
359 int len, namelen;
360
361 if (!name || !names)
362 return 0;
363
364 namelen = strlen(name);
365 while (*names) {
366 int negate = '-' == *names;
367 p = strchr(names, ',');
368 if (!p)
369 p = names + strlen(names);
370 names += negate;
371 len = FFMAX(p - names, namelen);
372 if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
373 return !negate;
374 names = p + (*p == ',');
375 }
376 return 0;
377 }
378
av_utf8_decode(int32_t * codep,const uint8_t ** bufp,const uint8_t * buf_end,unsigned int flags)379 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
380 unsigned int flags)
381 {
382 const uint8_t *p = *bufp;
383 uint32_t top;
384 uint64_t code;
385 int ret = 0, tail_len;
386 uint32_t overlong_encoding_mins[6] = {
387 0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
388 };
389
390 if (p >= buf_end)
391 return 0;
392
393 code = *p++;
394
395 /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
396 which is not admitted */
397 if ((code & 0xc0) == 0x80 || code >= 0xFE) {
398 ret = AVERROR(EILSEQ);
399 goto end;
400 }
401 top = (code & 128) >> 1;
402
403 tail_len = 0;
404 while (code & top) {
405 int tmp;
406 tail_len++;
407 if (p >= buf_end) {
408 (*bufp) ++;
409 return AVERROR(EILSEQ); /* incomplete sequence */
410 }
411
412 /* we assume the byte to be in the form 10xx-xxxx */
413 tmp = *p++ - 128; /* strip leading 1 */
414 if (tmp>>6) {
415 (*bufp) ++;
416 return AVERROR(EILSEQ);
417 }
418 code = (code<<6) + tmp;
419 top <<= 5;
420 }
421 code &= (top << 1) - 1;
422
423 /* check for overlong encodings */
424 av_assert0(tail_len <= 5);
425 if (code < overlong_encoding_mins[tail_len]) {
426 ret = AVERROR(EILSEQ);
427 goto end;
428 }
429
430 if (code >= 1U<<31) {
431 ret = AVERROR(EILSEQ); /* out-of-range value */
432 goto end;
433 }
434
435 *codep = code;
436
437 if (code > 0x10FFFF &&
438 !(flags & AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES))
439 ret = AVERROR(EILSEQ);
440 if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
441 flags & AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES)
442 ret = AVERROR(EILSEQ);
443 if (code >= 0xD800 && code <= 0xDFFF &&
444 !(flags & AV_UTF8_FLAG_ACCEPT_SURROGATES))
445 ret = AVERROR(EILSEQ);
446 if ((code == 0xFFFE || code == 0xFFFF) &&
447 !(flags & AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS))
448 ret = AVERROR(EILSEQ);
449
450 end:
451 *bufp = p;
452 return ret;
453 }
454
av_match_list(const char * name,const char * list,char separator)455 int av_match_list(const char *name, const char *list, char separator)
456 {
457 const char *p, *q;
458
459 for (p = name; p && *p; ) {
460 for (q = list; q && *q; ) {
461 int k;
462 for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
463 if (k && (!p[k] || p[k] == separator))
464 return 1;
465 q = strchr(q, separator);
466 q += !!q;
467 }
468 p = strchr(p, separator);
469 p += !!p;
470 }
471
472 return 0;
473 }
474