added url_get_filename()
[libav.git] / libavformat / avio.c
1 /*
2 * Unbuffered io for ffmpeg system
3 * Copyright (c) 2001 Fabrice Bellard
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 #include "avformat.h"
20
21 URLProtocol *first_protocol = NULL;
22
23 int register_protocol(URLProtocol *protocol)
24 {
25 URLProtocol **p;
26 p = &first_protocol;
27 while (*p != NULL) p = &(*p)->next;
28 *p = protocol;
29 protocol->next = NULL;
30 return 0;
31 }
32
33 int url_open(URLContext **puc, const char *filename, int flags)
34 {
35 URLContext *uc;
36 URLProtocol *up;
37 const char *p;
38 char proto_str[128], *q;
39 int err;
40
41 p = filename;
42 q = proto_str;
43 while (*p != '\0' && *p != ':') {
44 if ((q - proto_str) < sizeof(proto_str) - 1)
45 *q++ = *p;
46 p++;
47 }
48 /* if the protocol has length 1, we consider it is a dos drive */
49 if (*p == '\0' || (q - proto_str) <= 1) {
50 strcpy(proto_str, "file");
51 } else {
52 *q = '\0';
53 }
54
55 up = first_protocol;
56 while (up != NULL) {
57 if (!strcmp(proto_str, up->name))
58 goto found;
59 up = up->next;
60 }
61 err = -ENOENT;
62 goto fail;
63 found:
64 uc = av_malloc(sizeof(URLContext) + strlen(filename));
65 if (!uc) {
66 err = -ENOMEM;
67 goto fail;
68 }
69 strcpy(uc->filename, filename);
70 uc->prot = up;
71 uc->flags = flags;
72 uc->is_streamed = 0; /* default = not streamed */
73 uc->max_packet_size = 0; /* default: stream file */
74 err = up->url_open(uc, filename, flags);
75 if (err < 0) {
76 av_free(uc);
77 *puc = NULL;
78 return err;
79 }
80 *puc = uc;
81 return 0;
82 fail:
83 *puc = NULL;
84 return err;
85 }
86
87 int url_read(URLContext *h, unsigned char *buf, int size)
88 {
89 int ret;
90 if (h->flags & URL_WRONLY)
91 return -EIO;
92 ret = h->prot->url_read(h, buf, size);
93 return ret;
94 }
95
96 int url_write(URLContext *h, unsigned char *buf, int size)
97 {
98 int ret;
99 if (!(h->flags & (URL_WRONLY | URL_RDWR)))
100 return -EIO;
101 /* avoid sending too big packets */
102 if (h->max_packet_size && size > h->max_packet_size)
103 return -EIO;
104 ret = h->prot->url_write(h, buf, size);
105 return ret;
106 }
107
108 offset_t url_seek(URLContext *h, offset_t pos, int whence)
109 {
110 offset_t ret;
111
112 if (!h->prot->url_seek)
113 return -EPIPE;
114 ret = h->prot->url_seek(h, pos, whence);
115 return ret;
116 }
117
118 int url_close(URLContext *h)
119 {
120 int ret;
121
122 ret = h->prot->url_close(h);
123 av_free(h);
124 return ret;
125 }
126
127 int url_exist(const char *filename)
128 {
129 URLContext *h;
130 if (url_open(&h, filename, URL_RDONLY) < 0)
131 return 0;
132 url_close(h);
133 return 1;
134 }
135
136 offset_t url_filesize(URLContext *h)
137 {
138 offset_t pos, size;
139
140 pos = url_seek(h, 0, SEEK_CUR);
141 size = url_seek(h, 0, SEEK_END);
142 url_seek(h, pos, SEEK_SET);
143 return size;
144 }
145
146 /*
147 * Return the maximum packet size associated to packetized file
148 * handle. If the file is not packetized (stream like http or file on
149 * disk), then 0 is returned.
150 *
151 * @param h file handle
152 * @return maximum packet size in bytes
153 */
154 int url_get_max_packet_size(URLContext *h)
155 {
156 return h->max_packet_size;
157 }
158
159 void url_get_filename(URLContext *h, char *buf, int buf_size)
160 {
161 pstrcpy(buf, buf_size, h->filename);
162 }