FFmpeg  4.0
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 char *av_d2str(double d)
140 {
141  char *str = av_malloc(16);
142  if (str)
143  snprintf(str, 16, "%f", d);
144  return str;
145 }
146 
147 #define WHITESPACES " \n\t\r"
148 
149 char *av_get_token(const char **buf, const char *term)
150 {
151  char *out = av_malloc(strlen(*buf) + 1);
152  char *ret = out, *end = out;
153  const char *p = *buf;
154  if (!out)
155  return NULL;
156  p += strspn(p, WHITESPACES);
157 
158  while (*p && !strspn(p, term)) {
159  char c = *p++;
160  if (c == '\\' && *p) {
161  *out++ = *p++;
162  end = out;
163  } else if (c == '\'') {
164  while (*p && *p != '\'')
165  *out++ = *p++;
166  if (*p) {
167  p++;
168  end = out;
169  }
170  } else {
171  *out++ = c;
172  }
173  }
174 
175  do
176  *out-- = 0;
177  while (out >= end && strspn(out, WHITESPACES));
178 
179  *buf = p;
180 
181  return ret;
182 }
183 
184 char *av_strtok(char *s, const char *delim, char **saveptr)
185 {
186  char *tok;
187 
188  if (!s && !(s = *saveptr))
189  return NULL;
190 
191  /* skip leading delimiters */
192  s += strspn(s, delim);
193 
194  /* s now points to the first non delimiter char, or to the end of the string */
195  if (!*s) {
196  *saveptr = NULL;
197  return NULL;
198  }
199  tok = s++;
200 
201  /* skip non delimiters */
202  s += strcspn(s, delim);
203  if (*s) {
204  *s = 0;
205  *saveptr = s+1;
206  } else {
207  *saveptr = NULL;
208  }
209 
210  return tok;
211 }
212 
213 int av_strcasecmp(const char *a, const char *b)
214 {
215  uint8_t c1, c2;
216  do {
217  c1 = av_tolower(*a++);
218  c2 = av_tolower(*b++);
219  } while (c1 && c1 == c2);
220  return c1 - c2;
221 }
222 
223 int av_strncasecmp(const char *a, const char *b, size_t n)
224 {
225  const char *end = a + n;
226  uint8_t c1, c2;
227  do {
228  c1 = av_tolower(*a++);
229  c2 = av_tolower(*b++);
230  } while (a < end && c1 && c1 == c2);
231  return c1 - c2;
232 }
233 
234 char *av_strireplace(const char *str, const char *from, const char *to)
235 {
236  char *ret = NULL;
237  const char *pstr2, *pstr = str;
238  size_t tolen = strlen(to), fromlen = strlen(from);
239  AVBPrint pbuf;
240 
242  while ((pstr2 = av_stristr(pstr, from))) {
243  av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);
244  pstr = pstr2 + fromlen;
245  av_bprint_append_data(&pbuf, to, tolen);
246  }
247  av_bprint_append_data(&pbuf, pstr, strlen(pstr));
248  if (!av_bprint_is_complete(&pbuf)) {
249  av_bprint_finalize(&pbuf, NULL);
250  } else {
251  av_bprint_finalize(&pbuf, &ret);
252  }
253 
254  return ret;
255 }
256 
257 const char *av_basename(const char *path)
258 {
259  char *p = strrchr(path, '/');
260 
261 #if HAVE_DOS_PATHS
262  char *q = strrchr(path, '\\');
263  char *d = strchr(path, ':');
264 
265  p = FFMAX3(p, q, d);
266 #endif
267 
268  if (!p)
269  return path;
270 
271  return p + 1;
272 }
273 
274 const char *av_dirname(char *path)
275 {
276  char *p = strrchr(path, '/');
277 
278 #if HAVE_DOS_PATHS
279  char *q = strrchr(path, '\\');
280  char *d = strchr(path, ':');
281 
282  d = d ? d + 1 : d;
283 
284  p = FFMAX3(p, q, d);
285 #endif
286 
287  if (!p)
288  return ".";
289 
290  *p = '\0';
291 
292  return path;
293 }
294 
295 char *av_append_path_component(const char *path, const char *component)
296 {
297  size_t p_len, c_len;
298  char *fullpath;
299 
300  if (!path)
301  return av_strdup(component);
302  if (!component)
303  return av_strdup(path);
304 
305  p_len = strlen(path);
306  c_len = strlen(component);
307  if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)
308  return NULL;
309  fullpath = av_malloc(p_len + c_len + 2);
310  if (fullpath) {
311  if (p_len) {
312  av_strlcpy(fullpath, path, p_len + 1);
313  if (c_len) {
314  if (fullpath[p_len - 1] != '/' && component[0] != '/')
315  fullpath[p_len++] = '/';
316  else if (fullpath[p_len - 1] == '/' && component[0] == '/')
317  p_len--;
318  }
319  }
320  av_strlcpy(&fullpath[p_len], component, c_len + 1);
321  fullpath[p_len + c_len] = 0;
322  }
323  return fullpath;
324 }
325 
326 int av_escape(char **dst, const char *src, const char *special_chars,
327  enum AVEscapeMode mode, int flags)
328 {
329  AVBPrint dstbuf;
330 
332  av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
333 
334  if (!av_bprint_is_complete(&dstbuf)) {
335  av_bprint_finalize(&dstbuf, NULL);
336  return AVERROR(ENOMEM);
337  } else {
338  av_bprint_finalize(&dstbuf, dst);
339  return dstbuf.len;
340  }
341 }
342 
343 int av_match_name(const char *name, const char *names)
344 {
345  const char *p;
346  int len, namelen;
347 
348  if (!name || !names)
349  return 0;
350 
351  namelen = strlen(name);
352  while (*names) {
353  int negate = '-' == *names;
354  p = strchr(names, ',');
355  if (!p)
356  p = names + strlen(names);
357  names += negate;
358  len = FFMAX(p - names, namelen);
359  if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
360  return !negate;
361  names = p + (*p == ',');
362  }
363  return 0;
364 }
365 
366 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
367  unsigned int flags)
368 {
369  const uint8_t *p = *bufp;
370  uint32_t top;
371  uint64_t code;
372  int ret = 0, tail_len;
373  uint32_t overlong_encoding_mins[6] = {
374  0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
375  };
376 
377  if (p >= buf_end)
378  return 0;
379 
380  code = *p++;
381 
382  /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
383  which is not admitted */
384  if ((code & 0xc0) == 0x80 || code >= 0xFE) {
385  ret = AVERROR(EILSEQ);
386  goto end;
387  }
388  top = (code & 128) >> 1;
389 
390  tail_len = 0;
391  while (code & top) {
392  int tmp;
393  tail_len++;
394  if (p >= buf_end) {
395  (*bufp) ++;
396  return AVERROR(EILSEQ); /* incomplete sequence */
397  }
398 
399  /* we assume the byte to be in the form 10xx-xxxx */
400  tmp = *p++ - 128; /* strip leading 1 */
401  if (tmp>>6) {
402  (*bufp) ++;
403  return AVERROR(EILSEQ);
404  }
405  code = (code<<6) + tmp;
406  top <<= 5;
407  }
408  code &= (top << 1) - 1;
409 
410  /* check for overlong encodings */
411  av_assert0(tail_len <= 5);
412  if (code < overlong_encoding_mins[tail_len]) {
413  ret = AVERROR(EILSEQ);
414  goto end;
415  }
416 
417  if (code >= 1U<<31) {
418  ret = AVERROR(EILSEQ); /* out-of-range value */
419  goto end;
420  }
421 
422  *codep = code;
423 
424  if (code > 0x10FFFF &&
426  ret = AVERROR(EILSEQ);
427  if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
429  ret = AVERROR(EILSEQ);
430  if (code >= 0xD800 && code <= 0xDFFF &&
432  ret = AVERROR(EILSEQ);
433  if ((code == 0xFFFE || code == 0xFFFF) &&
435  ret = AVERROR(EILSEQ);
436 
437 end:
438  *bufp = p;
439  return ret;
440 }
441 
442 int av_match_list(const char *name, const char *list, char separator)
443 {
444  const char *p, *q;
445 
446  for (p = name; p && *p; ) {
447  for (q = list; q && *q; ) {
448  int k;
449  for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
450  if (k && (!p[k] || p[k] == separator))
451  return 1;
452  q = strchr(q, separator);
453  q += !!q;
454  }
455  p = strchr(p, separator);
456  p += !!p;
457  }
458 
459  return 0;
460 }
const char * name
Definition: avisynth_c.h:775
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
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:366
int size
const char * fmt
Definition: avisynth_c.h:769
Memory handling functions.
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_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:326
#define vsnprintf
Definition: snprintf.h:36
const char * b
Definition: vf_curves.c:113
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:223
#define src
Definition: vp8dsp.c:254
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
#define WHITESPACES
Definition: avstring.c:147
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
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
const char * av_basename(const char *path)
Thread safe basename.
Definition: avstring.c:257
uint8_t
#define av_malloc(s)
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
const char * from
Definition: jacosubdec.c:65
char * av_d2str(double d)
Convert a number to an av_malloced string.
Definition: avstring.c:139
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
#define AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES
accept codepoints over 0x10FFFF
Definition: avstring.h:356
static int flags
Definition: log.c:55
static const uint64_t c1
Definition: murmur3.c:49
#define AV_UTF8_FLAG_ACCEPT_SURROGATES
accept UTF-16 surrogates codes
Definition: avstring.h:358
const char * to
Definition: webvttdec.c:34
#define U(x)
Definition: vp56_arith.h:37
static av_const int av_tolower(int c)
Locale-independent conversion of ASCII characters to lowercase.
Definition: avstring.h:241
#define AV_BPRINT_SIZE_UNLIMITED
#define s2
Definition: regdef.h:39
#define AVERROR(e)
Definition: error.h:43
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.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:442
simple assert() macros that are a bit more flexible than ISO C assert().
char * av_strireplace(const char *str, const char *from, const char *to)
Locale-independent strings replace.
Definition: avstring.c:234
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:343
#define FFMAX(a, b)
Definition: common.h:94
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_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:149
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
#define AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES
exclude control codes not accepted by XML
Definition: avstring.h:359
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:213
int32_t
int n
Definition: avisynth_c.h:684
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:251
void * buf
Definition: avisynth_c.h:690
static av_const int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
Definition: avstring.h:231
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
Definition: avstring.c:101
#define s1
Definition: regdef.h:38
#define snprintf
Definition: snprintf.h:34
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
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:184
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
char * av_append_path_component(const char *path, const char *component)
Append path component to the existing path.
Definition: avstring.c:295
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
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
common internal and external API header
static double c[64]
const char * av_dirname(char *path)
Thread safe dirname.
Definition: avstring.c:274
static const uint64_t c2
Definition: murmur3.c:50
int len
#define AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS
accept non-characters - 0xFFFE and 0xFFFF
Definition: avstring.h:357
FILE * out
Definition: movenc.c:54
AVEscapeMode
Definition: avstring.h:313
#define av_freep(p)
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83
#define FFMAX3(a, b, c)
Definition: common.h:95
static uint8_t tmp[11]
Definition: aes_ctr.c:26