1 /*
2 * Simple URL decoding function
3 * Copyright (c) 2012 Antti Seppälä
4 *
5 * References:
6 * RFC 3986: Uniform Resource Identifier (URI): Generic Syntax
7 * T. Berners-Lee et al. The Internet Society, 2005
8 *
9 * based on http://www.icosaedro.it/apache/urldecode.c
10 * from Umberto Salsi (salsi@icosaedro.it)
11 *
12 * This file is part of FFmpeg.
13 *
14 * FFmpeg is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU Lesser General Public
16 * License as published by the Free Software Foundation; either
17 * version 2.1 of the License, or (at your option) any later version.
18 *
19 * FFmpeg is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 * Lesser General Public License for more details.
23 *
24 * You should have received a copy of the GNU Lesser General Public
25 * License along with FFmpeg; if not, write to the Free Software
26 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 */
28
29 #include <string.h>
30
31 #include "libavutil/mem.h"
32 #include "libavutil/avstring.h"
33 #include "urldecode.h"
34
ff_urldecode(const char * url)35 char *ff_urldecode(const char *url)
36 {
37 int s = 0, d = 0, url_len = 0;
38 char c;
39 char *dest = NULL;
40
41 if (!url)
42 return NULL;
43
44 url_len = strlen(url) + 1;
45 dest = av_malloc(url_len);
46
47 if (!dest)
48 return NULL;
49
50 while (s < url_len) {
51 c = url[s++];
52
53 if (c == '%' && s + 2 < url_len) {
54 char c2 = url[s++];
55 char c3 = url[s++];
56 if (av_isxdigit(c2) && av_isxdigit(c3)) {
57 c2 = av_tolower(c2);
58 c3 = av_tolower(c3);
59
60 if (c2 <= '9')
61 c2 = c2 - '0';
62 else
63 c2 = c2 - 'a' + 10;
64
65 if (c3 <= '9')
66 c3 = c3 - '0';
67 else
68 c3 = c3 - 'a' + 10;
69
70 dest[d++] = 16 * c2 + c3;
71
72 } else { /* %zz or something other invalid */
73 dest[d++] = c;
74 dest[d++] = c2;
75 dest[d++] = c3;
76 }
77 } else if (c == '+') {
78 dest[d++] = ' ';
79 } else {
80 dest[d++] = c;
81 }
82
83 }
84
85 return dest;
86 }
87