FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
url.c
Go to the documentation of this file.
1 /*
2  * URL utility functions
3  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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 
23 #include "avformat.h"
24 #include "config.h"
25 #include "url.h"
26 #if CONFIG_NETWORK
27 #include "network.h"
28 #endif
29 #include "libavutil/avstring.h"
30 
31 /**
32  * @file
33  * URL utility functions.
34  */
35 
36 int ff_url_join(char *str, int size, const char *proto,
37  const char *authorization, const char *hostname,
38  int port, const char *fmt, ...)
39 {
40 #if CONFIG_NETWORK
41  struct addrinfo hints = { 0 }, *ai;
42 #endif
43 
44  str[0] = '\0';
45  if (proto)
46  av_strlcatf(str, size, "%s://", proto);
47  if (authorization && authorization[0])
48  av_strlcatf(str, size, "%s@", authorization);
49 #if CONFIG_NETWORK && defined(AF_INET6)
50  /* Determine if hostname is a numerical IPv6 address,
51  * properly escape it within [] in that case. */
52  hints.ai_flags = AI_NUMERICHOST;
53  if (!getaddrinfo(hostname, NULL, &hints, &ai)) {
54  if (ai->ai_family == AF_INET6) {
55  av_strlcat(str, "[", size);
56  av_strlcat(str, hostname, size);
57  av_strlcat(str, "]", size);
58  } else {
59  av_strlcat(str, hostname, size);
60  }
61  freeaddrinfo(ai);
62  } else
63 #endif
64  /* Not an IPv6 address, just output the plain string. */
65  av_strlcat(str, hostname, size);
66 
67  if (port >= 0)
68  av_strlcatf(str, size, ":%d", port);
69  if (fmt) {
70  va_list vl;
71  int len = strlen(str);
72 
73  va_start(vl, fmt);
74  vsnprintf(str + len, size > len ? size - len : 0, fmt, vl);
75  va_end(vl);
76  }
77  return strlen(str);
78 }
79 
80 void ff_make_absolute_url(char *buf, int size, const char *base,
81  const char *rel)
82 {
83  char *sep, *path_query;
84  /* Absolute path, relative to the current server */
85  if (base && strstr(base, "://") && rel[0] == '/') {
86  if (base != buf)
87  av_strlcpy(buf, base, size);
88  sep = strstr(buf, "://");
89  if (sep) {
90  /* Take scheme from base url */
91  if (rel[1] == '/') {
92  sep[1] = '\0';
93  } else {
94  /* Take scheme and host from base url */
95  sep += 3;
96  sep = strchr(sep, '/');
97  if (sep)
98  *sep = '\0';
99  }
100  }
101  av_strlcat(buf, rel, size);
102  return;
103  }
104  /* If rel actually is an absolute url, just copy it */
105  if (!base || strstr(rel, "://") || rel[0] == '/') {
106  av_strlcpy(buf, rel, size);
107  return;
108  }
109  if (base != buf)
110  av_strlcpy(buf, base, size);
111 
112  /* Strip off any query string from base */
113  path_query = strchr(buf, '?');
114  if (path_query != NULL)
115  *path_query = '\0';
116 
117  /* Is relative path just a new query part? */
118  if (rel[0] == '?') {
119  av_strlcat(buf, rel, size);
120  return;
121  }
122 
123  /* Remove the file name from the base url */
124  sep = strrchr(buf, '/');
125  if (sep)
126  sep[1] = '\0';
127  else
128  buf[0] = '\0';
129  while (av_strstart(rel, "../", NULL) && sep) {
130  /* Remove the path delimiter at the end */
131  sep[0] = '\0';
132  sep = strrchr(buf, '/');
133  /* If the next directory name to pop off is "..", break here */
134  if (!strcmp(sep ? &sep[1] : buf, "..")) {
135  /* Readd the slash we just removed */
136  av_strlcat(buf, "/", size);
137  break;
138  }
139  /* Cut off the directory name */
140  if (sep)
141  sep[1] = '\0';
142  else
143  buf[0] = '\0';
144  rel += 3;
145  }
146  av_strlcat(buf, rel, size);
147 }