c0f532278fabe90fb2ca86c5f224b22d0e966ed2
[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 AVIOInterruptCB interrupt_callback;
46 } URLContext;
47
48 typedef struct URLProtocol {
49 const char *name;
50 int (*url_open)( URLContext *h, const char *url, int flags);
51 int (*url_read)( URLContext *h, unsigned char *buf, int size);
52 int (*url_write)(URLContext *h, const unsigned char *buf, int size);
53 int64_t (*url_seek)( URLContext *h, int64_t pos, int whence);
54 int (*url_close)(URLContext *h);
55 struct URLProtocol *next;
56 int (*url_read_pause)(URLContext *h, int pause);
57 int64_t (*url_read_seek)(URLContext *h, int stream_index,
58 int64_t timestamp, int flags);
59 int (*url_get_file_handle)(URLContext *h);
60 int priv_data_size;
61 const AVClass *priv_data_class;
62 int flags;
63 int (*url_check)(URLContext *h, int mask);
64 } URLProtocol;
65 #endif
66
67 /**
68 * Create a URLContext for accessing to the resource indicated by
69 * url, but do not initiate the connection yet.
70 *
71 * @param puc pointer to the location where, in case of success, the
72 * function puts the pointer to the created URLContext
73 * @param flags flags which control how the resource indicated by url
74 * is to be opened
75 * @return 0 in case of success, a negative value corresponding to an
76 * AVERROR code in case of failure
77 */
78 int ffurl_alloc(URLContext **puc, const char *filename, int flags);
79
80 /**
81 * Connect an URLContext that has been allocated by ffurl_alloc
82 */
83 int ffurl_connect(URLContext *uc);
84
85 /**
86 * Create an URLContext for accessing to the resource indicated by
87 * url, and open it.
88 *
89 * @param puc pointer to the location where, in case of success, the
90 * function puts the pointer to the created URLContext
91 * @param flags flags which control how the resource indicated by url
92 * is to be opened
93 * @return 0 in case of success, a negative value corresponding to an
94 * AVERROR code in case of failure
95 */
96 int ffurl_open(URLContext **puc, const char *filename, int flags);
97
98 /**
99 * Read up to size bytes from the resource accessed by h, and store
100 * the read bytes in buf.
101 *
102 * @return The number of bytes actually read, or a negative value
103 * corresponding to an AVERROR code in case of error. A value of zero
104 * indicates that it is not possible to read more from the accessed
105 * resource (except if the value of the size argument is also zero).
106 */
107 int ffurl_read(URLContext *h, unsigned char *buf, int size);
108
109 /**
110 * Read as many bytes as possible (up to size), calling the
111 * read function multiple times if necessary.
112 * This makes special short-read handling in applications
113 * unnecessary, if the return value is < size then it is
114 * certain there was either an error or the end of file was reached.
115 */
116 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size);
117
118 /**
119 * Write size bytes from buf to the resource accessed by h.
120 *
121 * @return the number of bytes actually written, or a negative value
122 * corresponding to an AVERROR code in case of failure
123 */
124 int ffurl_write(URLContext *h, const unsigned char *buf, int size);
125
126 /**
127 * Change the position that will be used by the next read/write
128 * operation on the resource accessed by h.
129 *
130 * @param pos specifies the new position to set
131 * @param whence specifies how pos should be interpreted, it must be
132 * one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the
133 * current position), SEEK_END (seek from the end), or AVSEEK_SIZE
134 * (return the filesize of the requested resource, pos is ignored).
135 * @return a negative value corresponding to an AVERROR code in case
136 * of failure, or the resulting file position, measured in bytes from
137 * the beginning of the file. You can use this feature together with
138 * SEEK_CUR to read the current file position.
139 */
140 int64_t ffurl_seek(URLContext *h, int64_t pos, int whence);
141
142 /**
143 * Close the resource accessed by the URLContext h, and free the
144 * memory used by it.
145 *
146 * @return a negative value if an error condition occurred, 0
147 * otherwise
148 */
149 int ffurl_close(URLContext *h);
150
151 /**
152 * Return the filesize of the resource accessed by h, AVERROR(ENOSYS)
153 * if the operation is not supported by h, or another negative value
154 * corresponding to an AVERROR error code in case of failure.
155 */
156 int64_t ffurl_size(URLContext *h);
157
158 /**
159 * Return the file descriptor associated with this URL. For RTP, this
160 * will return only the RTP file descriptor, not the RTCP file descriptor.
161 *
162 * @return the file descriptor associated with this URL, or <0 on error.
163 */
164 int ffurl_get_file_handle(URLContext *h);
165
166 /**
167 * Register the URLProtocol protocol.
168 *
169 * @param size the size of the URLProtocol struct referenced
170 */
171 int ffurl_register_protocol(URLProtocol *protocol, int size);
172
173 /* udp.c */
174 int ff_udp_set_remote_url(URLContext *h, const char *uri);
175 int ff_udp_get_local_port(URLContext *h);
176
177 #endif /* AVFORMAT_URL_H */