d69d0bc5c54f080485c0451876e1cc021cd74c0f
[libav.git] / libavformat / url.h
1 /*
2 *
3 * This file is part of Libav.
4 *
5 * Libav 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 2.1 of the License, or (at your option) any later version.
9 *
10 * Libav 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 Libav; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20 /**
21 * @file
22 * unbuffered private I/O API
23 */
24
25 #ifndef AVFORMAT_URL_H
26 #define AVFORMAT_URL_H
27
28 #include "avio.h"
29 #include "libavformat/version.h"
30
31 #if !FF_API_OLD_AVIO
32 #define URL_PROTOCOL_FLAG_NESTED_SCHEME 1 /*< The protocol name can be the first part of a nested protocol scheme */
33
34 extern int (*url_interrupt_cb)(void);
35
36 typedef struct URLContext {
37 const AVClass *av_class; /**< information for av_log(). Set by url_open(). */
38 struct URLProtocol *prot;
39 void *priv_data;
40 char *filename; /**< specified URL */
41 int flags;
42 int max_packet_size; /**< if non zero, the stream is packetized with this max packet size */
43 int is_streamed; /**< true if streamed (no seek possible), default = false */
44 int is_connected;
45 } URLContext;
46
47 typedef struct URLProtocol {
48 const char *name;
49 int (*url_open)( URLContext *h, const char *url, int flags);
50 int (*url_read)( URLContext *h, unsigned char *buf, int size);
51 int (*url_write)(URLContext *h, const unsigned char *buf, int size);
52 int64_t (*url_seek)( URLContext *h, int64_t pos, int whence);
53 int (*url_close)(URLContext *h);
54 struct URLProtocol *next;
55 int (*url_read_pause)(URLContext *h, int pause);
56 int64_t (*url_read_seek)(URLContext *h, int stream_index,
57 int64_t timestamp, int flags);
58 int (*url_get_file_handle)(URLContext *h);
59 int priv_data_size;
60 const AVClass *priv_data_class;
61 int flags;
62 int (*url_check)(URLContext *h, int mask);
63 } URLProtocol;
64 #endif
65
66 /**
67 * Create a URLContext for accessing to the resource indicated by
68 * url, but do not initiate the connection yet.
69 *
70 * @param puc pointer to the location where, in case of success, the
71 * function puts the pointer to the created URLContext
72 * @param flags flags which control how the resource indicated by url
73 * is to be opened
74 * @return 0 in case of success, a negative value corresponding to an
75 * AVERROR code in case of failure
76 */
77 int ffurl_alloc(URLContext **puc, const char *filename, int flags);
78
79 /**
80 * Connect an URLContext that has been allocated by ffurl_alloc
81 */
82 int ffurl_connect(URLContext *uc);
83
84 /**
85 * Create an URLContext for accessing to the resource indicated by
86 * url, and open it.
87 *
88 * @param puc pointer to the location where, in case of success, the
89 * function puts the pointer to the created URLContext
90 * @param flags flags which control how the resource indicated by url
91 * is to be opened
92 * @return 0 in case of success, a negative value corresponding to an
93 * AVERROR code in case of failure
94 */
95 int ffurl_open(URLContext **puc, const char *filename, int flags);
96
97 /**
98 * Read up to size bytes from the resource accessed by h, and store
99 * the read bytes in buf.
100 *
101 * @return The number of bytes actually read, or a negative value
102 * corresponding to an AVERROR code in case of error. A value of zero
103 * indicates that it is not possible to read more from the accessed
104 * resource (except if the value of the size argument is also zero).
105 */
106 int ffurl_read(URLContext *h, unsigned char *buf, int size);
107
108 /**
109 * Read as many bytes as possible (up to size), calling the
110 * read function multiple times if necessary.
111 * This makes special short-read handling in applications
112 * unnecessary, if the return value is < size then it is
113 * certain there was either an error or the end of file was reached.
114 */
115 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size);
116
117 /**
118 * Write size bytes from buf to the resource accessed by h.
119 *
120 * @return the number of bytes actually written, or a negative value
121 * corresponding to an AVERROR code in case of failure
122 */
123 int ffurl_write(URLContext *h, const unsigned char *buf, int size);
124
125 /**
126 * Change the position that will be used by the next read/write
127 * operation on the resource accessed by h.
128 *
129 * @param pos specifies the new position to set
130 * @param whence specifies how pos should be interpreted, it must be
131 * one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the
132 * current position), SEEK_END (seek from the end), or AVSEEK_SIZE
133 * (return the filesize of the requested resource, pos is ignored).
134 * @return a negative value corresponding to an AVERROR code in case
135 * of failure, or the resulting file position, measured in bytes from
136 * the beginning of the file. You can use this feature together with
137 * SEEK_CUR to read the current file position.
138 */
139 int64_t ffurl_seek(URLContext *h, int64_t pos, int whence);
140
141 /**
142 * Close the resource accessed by the URLContext h, and free the
143 * memory used by it.
144 *
145 * @return a negative value if an error condition occurred, 0
146 * otherwise
147 */
148 int ffurl_close(URLContext *h);
149
150 /**
151 * Return the filesize of the resource accessed by h, AVERROR(ENOSYS)
152 * if the operation is not supported by h, or another negative value
153 * corresponding to an AVERROR error code in case of failure.
154 */
155 int64_t ffurl_size(URLContext *h);
156
157 /**
158 * Return the file descriptor associated with this URL. For RTP, this
159 * will return only the RTP file descriptor, not the RTCP file descriptor.
160 *
161 * @return the file descriptor associated with this URL, or <0 on error.
162 */
163 int ffurl_get_file_handle(URLContext *h);
164
165 /**
166 * Register the URLProtocol protocol.
167 *
168 * @param size the size of the URLProtocol struct referenced
169 */
170 int ffurl_register_protocol(URLProtocol *protocol, int size);
171
172 /* udp.c */
173 int ff_udp_set_remote_url(URLContext *h, const char *uri);
174 int ff_udp_get_local_port(URLContext *h);
175
176 #endif /* AVFORMAT_URL_H */