FFmpeg
avstring.c
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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  uint8_t c1, c2;
226  if (n <= 0)
227  return 0;
228  do {
229  c1 = av_tolower(*a++);
230  c2 = av_tolower(*b++);
231  } while (--n && c1 && c1 == c2);
232  return c1 - c2;
233 }
234 
235 char *av_strireplace(const char *str, const char *from, const char *to)
236 {
237  char *ret = NULL;
238  const char *pstr2, *pstr = str;
239  size_t tolen = strlen(to), fromlen = strlen(from);
240  AVBPrint pbuf;
241 
243  while ((pstr2 = av_stristr(pstr, from))) {
244  av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);
245  pstr = pstr2 + fromlen;
246  av_bprint_append_data(&pbuf, to, tolen);
247  }
248  av_bprint_append_data(&pbuf, pstr, strlen(pstr));
249  if (!av_bprint_is_complete(&pbuf)) {
250  av_bprint_finalize(&pbuf, NULL);
251  } else {
252  av_bprint_finalize(&pbuf, &ret);
253  }
254 
255  return ret;
256 }
257 
258 const char *av_basename(const char *path)
259 {
260  char *p = strrchr(path, '/');
261 
262 #if HAVE_DOS_PATHS
263  char *q = strrchr(path, '\\');
264  char *d = strchr(path, ':');
265 
266  p = FFMAX3(p, q, d);
267 #endif
268 
269  if (!p)
270  return path;
271 
272  return p + 1;
273 }
274 
275 const char *av_dirname(char *path)
276 {
277  char *p = strrchr(path, '/');
278 
279 #if HAVE_DOS_PATHS
280  char *q = strrchr(path, '\\');
281  char *d = strchr(path, ':');
282 
283  d = d ? d + 1 : d;
284 
285  p = FFMAX3(p, q, d);
286 #endif
287 
288  if (!p)
289  return ".";
290 
291  *p = '\0';
292 
293  return path;
294 }
295 
296 char *av_append_path_component(const char *path, const char *component)
297 {
298  size_t p_len, c_len;
299  char *fullpath;
300 
301  if (!path)
302  return av_strdup(component);
303  if (!component)
304  return av_strdup(path);
305 
306  p_len = strlen(path);
307  c_len = strlen(component);
308  if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)
309  return NULL;
310  fullpath = av_malloc(p_len + c_len + 2);
311  if (fullpath) {
312  if (p_len) {
313  av_strlcpy(fullpath, path, p_len + 1);
314  if (c_len) {
315  if (fullpath[p_len - 1] != '/' && component[0] != '/')
316  fullpath[p_len++] = '/';
317  else if (fullpath[p_len - 1] == '/' && component[0] == '/')
318  p_len--;
319  }
320  }
321  av_strlcpy(&fullpath[p_len], component, c_len + 1);
322  fullpath[p_len + c_len] = 0;
323  }
324  return fullpath;
325 }
326 
327 int av_escape(char **dst, const char *src, const char *special_chars,
328  enum AVEscapeMode mode, int flags)
329 {
330  AVBPrint dstbuf;
331 
333  av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
334 
335  if (!av_bprint_is_complete(&dstbuf)) {
336  av_bprint_finalize(&dstbuf, NULL);
337  return AVERROR(ENOMEM);
338  } else {
339  av_bprint_finalize(&dstbuf, dst);
340  return dstbuf.len;
341  }
342 }
343 
344 int av_match_name(const char *name, const char *names)
345 {
346  const char *p;
347  int len, namelen;
348 
349  if (!name || !names)
350  return 0;
351 
352  namelen = strlen(name);
353  while (*names) {
354  int negate = '-' == *names;
355  p = strchr(names, ',');
356  if (!p)
357  p = names + strlen(names);
358  names += negate;
359  len = FFMAX(p - names, namelen);
360  if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
361  return !negate;
362  names = p + (*p == ',');
363  }
364  return 0;
365 }
366 
367 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
368  unsigned int flags)
369 {
370  const uint8_t *p = *bufp;
371  uint32_t top;
372  uint64_t code;
373  int ret = 0, tail_len;
374  uint32_t overlong_encoding_mins[6] = {
375  0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
376  };
377 
378  if (p >= buf_end)
379  return 0;
380 
381  code = *p++;
382 
383  /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
384  which is not admitted */
385  if ((code & 0xc0) == 0x80 || code >= 0xFE) {
386  ret = AVERROR(EILSEQ);
387  goto end;
388  }
389  top = (code & 128) >> 1;
390 
391  tail_len = 0;
392  while (code & top) {
393  int tmp;
394  tail_len++;
395  if (p >= buf_end) {
396  (*bufp) ++;
397  return AVERROR(EILSEQ); /* incomplete sequence */
398  }
399 
400  /* we assume the byte to be in the form 10xx-xxxx */
401  tmp = *p++ - 128; /* strip leading 1 */
402  if (tmp>>6) {
403  (*bufp) ++;
404  return AVERROR(EILSEQ);
405  }
406  code = (code<<6) + tmp;
407  top <<= 5;
408  }
409  code &= (top << 1) - 1;
410 
411  /* check for overlong encodings */
412  av_assert0(tail_len <= 5);
413  if (code < overlong_encoding_mins[tail_len]) {
414  ret = AVERROR(EILSEQ);
415  goto end;
416  }
417 
418  if (code >= 1U<<31) {
419  ret = AVERROR(EILSEQ); /* out-of-range value */
420  goto end;
421  }
422 
423  *codep = code;
424 
425  if (code > 0x10FFFF &&
427  ret = AVERROR(EILSEQ);
428  if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
430  ret = AVERROR(EILSEQ);
431  if (code >= 0xD800 && code <= 0xDFFF &&
433  ret = AVERROR(EILSEQ);
434  if ((code == 0xFFFE || code == 0xFFFF) &&
436  ret = AVERROR(EILSEQ);
437 
438 end:
439  *bufp = p;
440  return ret;
441 }
442 
443 int av_match_list(const char *name, const char *list, char separator)
444 {
445  const char *p, *q;
446 
447  for (p = name; p && *p; ) {
448  for (q = list; q && *q; ) {
449  int k;
450  for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
451  if (k && (!p[k] || p[k] == separator))
452  return 1;
453  q = strchr(q, separator);
454  q += !!q;
455  }
456  p = strchr(p, separator);
457  p += !!p;
458  }
459 
460  return 0;
461 }
#define NULL
Definition: coverity.c:32
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:367
const char * fmt
Definition: avisynth_c.h:861
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:327
#define vsnprintf
Definition: snprintf.h:36
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:223
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
#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:258
uint8_t
#define av_malloc(s)
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
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 const uint64_t c1
Definition: murmur3.c:49
ptrdiff_t size
Definition: opengl_enc.c:100
#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
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:443
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:235
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:344
#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 b
Definition: input.c:41
#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
#define s(width, name)
Definition: cbs_vp9.c:257
int n
Definition: avisynth_c.h:760
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
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining list
void * buf
Definition: avisynth_c.h:766
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
#define flags(name, subs,...)
Definition: cbs_av1.c:561
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
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:296
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
const char * av_dirname(char *path)
Thread safe dirname.
Definition: avstring.c:275
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)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83
#define FFMAX3(a, b, c)
Definition: common.h:95
const char * name
Definition: opengl_enc.c:102
static uint8_t tmp[11]
Definition: aes_ctr.c:26