FFmpeg  4.4.4
avstring.c
Go to the documentation of this file.
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 <stdarg.h>
23 #include <stdint.h>
24 #include <stdio.h>
25 #include <string.h>
26 
27 #include "config.h"
28 #include "common.h"
29 #include "mem.h"
30 #include "avassert.h"
31 #include "avstring.h"
32 #include "bprint.h"
33 
34 int av_strstart(const char *str, const char *pfx, const char **ptr)
35 {
36  while (*pfx && *pfx == *str) {
37  pfx++;
38  str++;
39  }
40  if (!*pfx && ptr)
41  *ptr = str;
42  return !*pfx;
43 }
44 
45 int av_stristart(const char *str, const char *pfx, const char **ptr)
46 {
47  while (*pfx && av_toupper((unsigned)*pfx) == av_toupper((unsigned)*str)) {
48  pfx++;
49  str++;
50  }
51  if (!*pfx && ptr)
52  *ptr = str;
53  return !*pfx;
54 }
55 
56 char *av_stristr(const char *s1, const char *s2)
57 {
58  if (!*s2)
59  return (char*)(intptr_t)s1;
60 
61  do
62  if (av_stristart(s1, s2, NULL))
63  return (char*)(intptr_t)s1;
64  while (*s1++);
65 
66  return NULL;
67 }
68 
69 char *av_strnstr(const char *haystack, const char *needle, size_t hay_length)
70 {
71  size_t needle_len = strlen(needle);
72  if (!needle_len)
73  return (char*)haystack;
74  while (hay_length >= needle_len) {
75  hay_length--;
76  if (!memcmp(haystack, needle, needle_len))
77  return (char*)haystack;
78  haystack++;
79  }
80  return NULL;
81 }
82 
83 size_t av_strlcpy(char *dst, const char *src, size_t size)
84 {
85  size_t len = 0;
86  while (++len < size && *src)
87  *dst++ = *src++;
88  if (len <= size)
89  *dst = 0;
90  return len + strlen(src) - 1;
91 }
92 
93 size_t av_strlcat(char *dst, const char *src, size_t size)
94 {
95  size_t len = strlen(dst);
96  if (size <= len + 1)
97  return len + strlen(src);
98  return len + av_strlcpy(dst + len, src, size - len);
99 }
100 
101 size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...)
102 {
103  size_t len = strlen(dst);
104  va_list vl;
105 
106  va_start(vl, fmt);
107  len += vsnprintf(dst + len, size > len ? size - len : 0, fmt, vl);
108  va_end(vl);
109 
110  return len;
111 }
112 
113 char *av_asprintf(const char *fmt, ...)
114 {
115  char *p = NULL;
116  va_list va;
117  int len;
118 
119  va_start(va, fmt);
120  len = vsnprintf(NULL, 0, fmt, va);
121  va_end(va);
122  if (len < 0)
123  goto end;
124 
125  p = av_malloc(len + 1);
126  if (!p)
127  goto end;
128 
129  va_start(va, fmt);
130  len = vsnprintf(p, len + 1, fmt, va);
131  va_end(va);
132  if (len < 0)
133  av_freep(&p);
134 
135 end:
136  return p;
137 }
138 
139 #if FF_API_D2STR
140 char *av_d2str(double d)
141 {
142  char *str = av_malloc(16);
143  if (str)
144  snprintf(str, 16, "%f", d);
145  return str;
146 }
147 #endif
148 
149 #define WHITESPACES " \n\t\r"
150 
151 char *av_get_token(const char **buf, const char *term)
152 {
153  char *out = av_malloc(strlen(*buf) + 1);
154  char *ret = out, *end = out;
155  const char *p = *buf;
156  if (!out)
157  return NULL;
158  p += strspn(p, WHITESPACES);
159 
160  while (*p && !strspn(p, term)) {
161  char c = *p++;
162  if (c == '\\' && *p) {
163  *out++ = *p++;
164  end = out;
165  } else if (c == '\'') {
166  while (*p && *p != '\'')
167  *out++ = *p++;
168  if (*p) {
169  p++;
170  end = out;
171  }
172  } else {
173  *out++ = c;
174  }
175  }
176 
177  do
178  *out-- = 0;
179  while (out >= end && strspn(out, WHITESPACES));
180 
181  *buf = p;
182 
183  return ret;
184 }
185 
186 char *av_strtok(char *s, const char *delim, char **saveptr)
187 {
188  char *tok;
189 
190  if (!s && !(s = *saveptr))
191  return NULL;
192 
193  /* skip leading delimiters */
194  s += strspn(s, delim);
195 
196  /* s now points to the first non delimiter char, or to the end of the string */
197  if (!*s) {
198  *saveptr = NULL;
199  return NULL;
200  }
201  tok = s++;
202 
203  /* skip non delimiters */
204  s += strcspn(s, delim);
205  if (*s) {
206  *s = 0;
207  *saveptr = s+1;
208  } else {
209  *saveptr = NULL;
210  }
211 
212  return tok;
213 }
214 
215 int av_strcasecmp(const char *a, const char *b)
216 {
217  uint8_t c1, c2;
218  do {
219  c1 = av_tolower(*a++);
220  c2 = av_tolower(*b++);
221  } while (c1 && c1 == c2);
222  return c1 - c2;
223 }
224 
225 int av_strncasecmp(const char *a, const char *b, size_t n)
226 {
227  uint8_t c1, c2;
228  if (n <= 0)
229  return 0;
230  do {
231  c1 = av_tolower(*a++);
232  c2 = av_tolower(*b++);
233  } while (--n && c1 && c1 == c2);
234  return c1 - c2;
235 }
236 
237 char *av_strireplace(const char *str, const char *from, const char *to)
238 {
239  char *ret = NULL;
240  const char *pstr2, *pstr = str;
241  size_t tolen = strlen(to), fromlen = strlen(from);
242  AVBPrint pbuf;
243 
245  while ((pstr2 = av_stristr(pstr, from))) {
246  av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);
247  pstr = pstr2 + fromlen;
248  av_bprint_append_data(&pbuf, to, tolen);
249  }
250  av_bprint_append_data(&pbuf, pstr, strlen(pstr));
251  if (!av_bprint_is_complete(&pbuf)) {
252  av_bprint_finalize(&pbuf, NULL);
253  } else {
254  av_bprint_finalize(&pbuf, &ret);
255  }
256 
257  return ret;
258 }
259 
260 const char *av_basename(const char *path)
261 {
262  char *p;
263 #if HAVE_DOS_PATHS
264  char *q, *d;
265 #endif
266 
267  if (!path || *path == '\0')
268  return ".";
269 
270  p = strrchr(path, '/');
271 #if HAVE_DOS_PATHS
272  q = strrchr(path, '\\');
273  d = strchr(path, ':');
274  p = FFMAX3(p, q, d);
275 #endif
276 
277  if (!p)
278  return path;
279 
280  return p + 1;
281 }
282 
283 const char *av_dirname(char *path)
284 {
285  char *p = path ? strrchr(path, '/') : NULL;
286 
287 #if HAVE_DOS_PATHS
288  char *q = path ? strrchr(path, '\\') : NULL;
289  char *d = path ? strchr(path, ':') : NULL;
290 
291  d = d ? d + 1 : d;
292 
293  p = FFMAX3(p, q, d);
294 #endif
295 
296  if (!p)
297  return ".";
298 
299  *p = '\0';
300 
301  return path;
302 }
303 
304 char *av_append_path_component(const char *path, const char *component)
305 {
306  size_t p_len, c_len;
307  char *fullpath;
308 
309  if (!path)
310  return av_strdup(component);
311  if (!component)
312  return av_strdup(path);
313 
314  p_len = strlen(path);
315  c_len = strlen(component);
316  if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)
317  return NULL;
318  fullpath = av_malloc(p_len + c_len + 2);
319  if (fullpath) {
320  if (p_len) {
321  av_strlcpy(fullpath, path, p_len + 1);
322  if (c_len) {
323  if (fullpath[p_len - 1] != '/' && component[0] != '/')
324  fullpath[p_len++] = '/';
325  else if (fullpath[p_len - 1] == '/' && component[0] == '/')
326  p_len--;
327  }
328  }
329  av_strlcpy(&fullpath[p_len], component, c_len + 1);
330  fullpath[p_len + c_len] = 0;
331  }
332  return fullpath;
333 }
334 
335 int av_escape(char **dst, const char *src, const char *special_chars,
336  enum AVEscapeMode mode, int flags)
337 {
338  AVBPrint dstbuf;
339  int ret;
340 
341  av_bprint_init(&dstbuf, 1, INT_MAX); /* (int)dstbuf.len must be >= 0 */
342  av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
343 
344  if (!av_bprint_is_complete(&dstbuf)) {
345  av_bprint_finalize(&dstbuf, NULL);
346  return AVERROR(ENOMEM);
347  }
348  if ((ret = av_bprint_finalize(&dstbuf, dst)) < 0)
349  return ret;
350  return dstbuf.len;
351 }
352 
353 int av_match_name(const char *name, const char *names)
354 {
355  const char *p;
356  int len, namelen;
357 
358  if (!name || !names)
359  return 0;
360 
361  namelen = strlen(name);
362  while (*names) {
363  int negate = '-' == *names;
364  p = strchr(names, ',');
365  if (!p)
366  p = names + strlen(names);
367  names += negate;
368  len = FFMAX(p - names, namelen);
369  if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
370  return !negate;
371  names = p + (*p == ',');
372  }
373  return 0;
374 }
375 
376 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
377  unsigned int flags)
378 {
379  const uint8_t *p = *bufp;
380  uint32_t top;
381  uint64_t code;
382  int ret = 0, tail_len;
383  uint32_t overlong_encoding_mins[6] = {
384  0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
385  };
386 
387  if (p >= buf_end)
388  return 0;
389 
390  code = *p++;
391 
392  /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
393  which is not admitted */
394  if ((code & 0xc0) == 0x80 || code >= 0xFE) {
395  ret = AVERROR(EILSEQ);
396  goto end;
397  }
398  top = (code & 128) >> 1;
399 
400  tail_len = 0;
401  while (code & top) {
402  int tmp;
403  tail_len++;
404  if (p >= buf_end) {
405  (*bufp) ++;
406  return AVERROR(EILSEQ); /* incomplete sequence */
407  }
408 
409  /* we assume the byte to be in the form 10xx-xxxx */
410  tmp = *p++ - 128; /* strip leading 1 */
411  if (tmp>>6) {
412  (*bufp) ++;
413  return AVERROR(EILSEQ);
414  }
415  code = (code<<6) + tmp;
416  top <<= 5;
417  }
418  code &= (top << 1) - 1;
419 
420  /* check for overlong encodings */
421  av_assert0(tail_len <= 5);
422  if (code < overlong_encoding_mins[tail_len]) {
423  ret = AVERROR(EILSEQ);
424  goto end;
425  }
426 
427  if (code >= 1U<<31) {
428  ret = AVERROR(EILSEQ); /* out-of-range value */
429  goto end;
430  }
431 
432  *codep = code;
433 
434  if (code > 0x10FFFF &&
436  ret = AVERROR(EILSEQ);
437  if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
439  ret = AVERROR(EILSEQ);
440  if (code >= 0xD800 && code <= 0xDFFF &&
442  ret = AVERROR(EILSEQ);
443  if ((code == 0xFFFE || code == 0xFFFF) &&
445  ret = AVERROR(EILSEQ);
446 
447 end:
448  *bufp = p;
449  return ret;
450 }
451 
452 int av_match_list(const char *name, const char *list, char separator)
453 {
454  const char *p, *q;
455 
456  for (p = name; p && *p; ) {
457  for (q = list; q && *q; ) {
458  int k;
459  for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
460  if (k && (!p[k] || p[k] == separator))
461  return 1;
462  q = strchr(q, separator);
463  q += !!q;
464  }
465  p = strchr(p, separator);
466  p += !!p;
467  }
468 
469  return 0;
470 }
uint8_t
int32_t
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
Definition: avstring.c:101
#define WHITESPACES
Definition: avstring.c:149
void av_bprint_escape(AVBPrint *dstbuf, const char *src, const char *special_chars, enum AVEscapeMode mode, int flags)
Escape the content in src and append it to dstbuf.
Definition: bprint.c:265
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
#define AV_BPRINT_SIZE_UNLIMITED
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
common internal and external API header
#define FFMAX3(a, b, c)
Definition: common.h:104
#define FFMAX(a, b)
Definition: common.h:103
#define NULL
Definition: coverity.c:32
mode
Use these values in ebur128_init (or'ed).
Definition: ebur128.h:83
#define AVERROR(e)
Definition: error.h:43
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:253
size_t av_strlcat(char *dst, const char *src, size_t size)
Append the string src to the string dst, but to a total length of no more than size - 1 bytes,...
Definition: avstring.c:93
const char * av_basename(const char *path)
Thread safe basename.
Definition: avstring.c:260
#define AV_UTF8_FLAG_ACCEPT_SURROGATES
accept UTF-16 surrogates codes
Definition: avstring.h:382
int av_escape(char **dst, const char *src, const char *special_chars, enum AVEscapeMode mode, int flags)
Escape string in src, and put the escaped string in an allocated string in *dst, which must be freed ...
Definition: avstring.c:335
char * av_strtok(char *s, const char *delim, char **saveptr)
Split the string into several tokens which can be accessed by successive calls to av_strtok().
Definition: avstring.c:186
static av_const int av_tolower(int c)
Locale-independent conversion of ASCII characters to lowercase.
Definition: avstring.h:246
char * av_stristr(const char *s1, const char *s2)
Locate the first case-independent occurrence in the string haystack of the string needle.
Definition: avstring.c:56
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:215
int av_match_name(const char *name, const char *names)
Match instances of a name in a comma-separated list of names.
Definition: avstring.c:353
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:34
#define AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES
accept codepoints over 0x10FFFF
Definition: avstring.h:380
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:83
char * av_d2str(double d)
Convert a number to an av_malloced string.
Definition: avstring.c:140
char * av_append_path_component(const char *path, const char *component)
Append path component to the existing path.
Definition: avstring.c:304
char * av_get_token(const char **buf, const char *term)
Unescape the given string until a non escaped terminating char, and return the token corresponding to...
Definition: avstring.c:151
char * av_strnstr(const char *haystack, const char *needle, size_t hay_length)
Locate the first occurrence of the string needle in the string haystack where not more than hay_lengt...
Definition: avstring.c:69
int av_match_list(const char *name, const char *list, char separator)
Check if a name is in a list.
Definition: avstring.c:452
static av_const int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
Definition: avstring.h:236
const char * av_dirname(char *path)
Thread safe dirname.
Definition: avstring.c:283
int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end, unsigned int flags)
Read and decode a single UTF-8 code point (character) from the buffer in *buf, and update *buf to poi...
Definition: avstring.c:376
int av_stristart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str independent of case.
Definition: avstring.c:45
#define AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS
accept non-characters - 0xFFFE and 0xFFFF
Definition: avstring.h:381
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:225
#define AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES
exclude control codes not accepted by XML
Definition: avstring.h:383
AVEscapeMode
Definition: avstring.h:323
char * av_strireplace(const char *str, const char *from, const char *to)
Locale-independent strings replace.
Definition: avstring.c:237
const char * from
Definition: jacosubdec.c:65
const char * to
Definition: webvttdec.c:34
Memory handling functions.
static const uint64_t c2
Definition: murmur3.c:52
static const uint64_t c1
Definition: murmur3.c:51
const char * name
Definition: qsvenc.c:46
#define s1
Definition: regdef.h:38
#define s2
Definition: regdef.h:39
#define vsnprintf
Definition: snprintf.h:36
#define snprintf
Definition: snprintf.h:34
const uint8_t * code
Definition: spdifenc.c:413
#define av_freep(p)
#define av_malloc(s)
static uint8_t tmp[11]
Definition: aes_ctr.c:27
#define src
Definition: vp8dsp.c:255
FILE * out
Definition: movenc.c:54
int size
const char * b
Definition: vf_curves.c:118
int len
static double c[64]