yading@11: /*
yading@11:  * Simple URL decoding function
yading@11:  * Copyright (c) 2012 Antti Seppälä
yading@11:  *
yading@11:  * References:
yading@11:  *  RFC 3986: Uniform Resource Identifier (URI): Generic Syntax
yading@11:  *       T. Berners-Lee et al. The Internet Society, 2005
yading@11:  *
yading@11:  * based on http://www.icosaedro.it/apache/urldecode.c
yading@11:  *          from Umberto Salsi (salsi@icosaedro.it)
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include <string.h>
yading@11: 
yading@11: #include "libavutil/mem.h"
yading@11: #include "libavutil/avstring.h"
yading@11: #include "urldecode.h"
yading@11: 
yading@11: char *ff_urldecode(const char *url)
yading@11: {
yading@11:     int s = 0, d = 0, url_len = 0;
yading@11:     char c;
yading@11:     char *dest = NULL;
yading@11: 
yading@11:     if (!url)
yading@11:         return NULL;
yading@11: 
yading@11:     url_len = strlen(url) + 1;
yading@11:     dest = av_malloc(url_len);
yading@11: 
yading@11:     if (!dest)
yading@11:         return NULL;
yading@11: 
yading@11:     while (s < url_len) {
yading@11:         c = url[s++];
yading@11: 
yading@11:         if (c == '%' && s + 2 < url_len) {
yading@11:             char c2 = url[s++];
yading@11:             char c3 = url[s++];
yading@11:             if (av_isxdigit(c2) && av_isxdigit(c3)) {
yading@11:                 c2 = av_tolower(c2);
yading@11:                 c3 = av_tolower(c3);
yading@11: 
yading@11:                 if (c2 <= '9')
yading@11:                     c2 = c2 - '0';
yading@11:                 else
yading@11:                     c2 = c2 - 'a' + 10;
yading@11: 
yading@11:                 if (c3 <= '9')
yading@11:                     c3 = c3 - '0';
yading@11:                 else
yading@11:                     c3 = c3 - 'a' + 10;
yading@11: 
yading@11:                 dest[d++] = 16 * c2 + c3;
yading@11: 
yading@11:             } else { /* %zz or something other invalid */
yading@11:                 dest[d++] = c;
yading@11:                 dest[d++] = c2;
yading@11:                 dest[d++] = c3;
yading@11:             }
yading@11:         } else if (c == '+') {
yading@11:             dest[d++] = ' ';
yading@11:         } else {
yading@11:             dest[d++] = c;
yading@11:         }
yading@11: 
yading@11:     }
yading@11: 
yading@11:     return dest;
yading@11: }