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 #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 
341  av_bprint_escape(&dstbuf, src, special_chars, mode, flags);
342 
343  if (!av_bprint_is_complete(&dstbuf)) {
344  av_bprint_finalize(&dstbuf, NULL);
345  return AVERROR(ENOMEM);
346  } else {
347  av_bprint_finalize(&dstbuf, dst);
348  return dstbuf.len;
349  }
350 }
351 
352 int av_match_name(const char *name, const char *names)
353 {
354  const char *p;
355  int len, namelen;
356 
357  if (!name || !names)
358  return 0;
359 
360  namelen = strlen(name);
361  while (*names) {
362  int negate = '-' == *names;
363  p = strchr(names, ',');
364  if (!p)
365  p = names + strlen(names);
366  names += negate;
367  len = FFMAX(p - names, namelen);
368  if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))
369  return !negate;
370  names = p + (*p == ',');
371  }
372  return 0;
373 }
374 
375 int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,
376  unsigned int flags)
377 {
378  const uint8_t *p = *bufp;
379  uint32_t top;
380  uint64_t code;
381  int ret = 0, tail_len;
382  uint32_t overlong_encoding_mins[6] = {
383  0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,
384  };
385 
386  if (p >= buf_end)
387  return 0;
388 
389  code = *p++;
390 
391  /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,
392  which is not admitted */
393  if ((code & 0xc0) == 0x80 || code >= 0xFE) {
394  ret = AVERROR(EILSEQ);
395  goto end;
396  }
397  top = (code & 128) >> 1;
398 
399  tail_len = 0;
400  while (code & top) {
401  int tmp;
402  tail_len++;
403  if (p >= buf_end) {
404  (*bufp) ++;
405  return AVERROR(EILSEQ); /* incomplete sequence */
406  }
407 
408  /* we assume the byte to be in the form 10xx-xxxx */
409  tmp = *p++ - 128; /* strip leading 1 */
410  if (tmp>>6) {
411  (*bufp) ++;
412  return AVERROR(EILSEQ);
413  }
414  code = (code<<6) + tmp;
415  top <<= 5;
416  }
417  code &= (top << 1) - 1;
418 
419  /* check for overlong encodings */
420  av_assert0(tail_len <= 5);
421  if (code < overlong_encoding_mins[tail_len]) {
422  ret = AVERROR(EILSEQ);
423  goto end;
424  }
425 
426  if (code >= 1U<<31) {
427  ret = AVERROR(EILSEQ); /* out-of-range value */
428  goto end;
429  }
430 
431  *codep = code;
432 
433  if (code > 0x10FFFF &&
435  ret = AVERROR(EILSEQ);
436  if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&
438  ret = AVERROR(EILSEQ);
439  if (code >= 0xD800 && code <= 0xDFFF &&
441  ret = AVERROR(EILSEQ);
442  if ((code == 0xFFFE || code == 0xFFFF) &&
444  ret = AVERROR(EILSEQ);
445 
446 end:
447  *bufp = p;
448  return ret;
449 }
450 
451 int av_match_list(const char *name, const char *list, char separator)
452 {
453  const char *p, *q;
454 
455  for (p = name; p && *p; ) {
456  for (q = list; q && *q; ) {
457  int k;
458  for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)
459  if (k && (!p[k] || p[k] == separator))
460  return 1;
461  q = strchr(q, separator);
462  q += !!q;
463  }
464  p = strchr(p, separator);
465  p += !!p;
466  }
467 
468  return 0;
469 }
#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:375
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:335
#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:225
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
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
char * av_d2str(double d)
Convert a number to an av_malloced string.
Definition: avstring.c:140
#define WHITESPACES
Definition: avstring.c:149
#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:260
uint8_t
#define av_malloc(s)
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
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
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:366
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:368
const char * to
Definition: webvttdec.c:34
#define U(x)
Definition: vp56_arith.h:37
#define src
Definition: vp8dsp.c:254
static av_const int av_tolower(int c)
Locale-independent conversion of ASCII characters to lowercase.
Definition: avstring.h:246
#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
unsigned char * buf
Definition: avsscanf.c:39
int av_match_list(const char *name, const char *list, char separator)
Check if a name is in a list.
Definition: avstring.c:451
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:237
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:352
#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:151
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:369
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:215
int32_t
#define s(width, name)
Definition: cbs_vp9.c:257
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:253
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
static av_const int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
Definition: avstring.h:236
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:560
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:186
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:304
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:283
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:367
FILE * out
Definition: movenc.c:54
AVEscapeMode
Definition: avstring.h:323
#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