xref: /third_party/ffmpeg/libavutil/avstring.c (revision cabdff1a)
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
37int 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
48int 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
59char *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
72char *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
86size_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
96size_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
104size_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
116char *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
138end:
139    return p;
140}
141
142#if FF_API_D2STR
143char *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
154char *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
189char *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
218int 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
228int 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
240char *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
263const 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
286const 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
307char *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
338int 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
356int 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
379int 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
450end:
451    *bufp = p;
452    return ret;
453}
454
455int 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