2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * unbuffered private I/O API
24 #ifndef AVFORMAT_URL_H
25 #define AVFORMAT_URL_H
29 #include "libavutil/dict.h"
30 #include "libavutil/log.h"
32 #define URL_PROTOCOL_FLAG_NESTED_SCHEME 1 /*< The protocol name can be the first part of a nested protocol scheme */
33 #define URL_PROTOCOL_FLAG_NETWORK 2 /*< The protocol uses network */
35 extern const AVClass ffurl_context_class;
37 typedef struct URLContext {
38 const AVClass *av_class; /**< information for av_log(). Set by url_open(). */
39 const struct URLProtocol *prot;
41 char *filename; /**< specified URL */
43 int max_packet_size; /**< if non zero, the stream is packetized with this max packet size */
44 int is_streamed; /**< true if streamed (no seek possible), default = false */
46 AVIOInterruptCB interrupt_callback;
47 int64_t rw_timeout; /**< maximum time to wait for (network) read/write operation completion, in mcs */
48 const char *protocol_whitelist;
49 const char *protocol_blacklist;
50 int min_packet_size; /**< if non zero, the stream is packetized with this min packet size */
53 typedef struct URLProtocol {
55 int (*url_open)( URLContext *h, const char *url, int flags);
57 * This callback is to be used by protocols which open further nested
58 * protocols. options are then to be passed to ffurl_open_whitelist()
59 * or ffurl_connect() for those nested protocols.
61 int (*url_open2)(URLContext *h, const char *url, int flags, AVDictionary **options);
62 int (*url_accept)(URLContext *s, URLContext **c);
63 int (*url_handshake)(URLContext *c);
66 * Read data from the protocol.
67 * If data is immediately available (even less than size), EOF is
68 * reached or an error occurs (including EINTR), return immediately.
70 * In non-blocking mode, return AVERROR(EAGAIN) immediately.
71 * In blocking mode, wait for data/EOF/error with a short timeout (0.1s),
72 * and return AVERROR(EAGAIN) on timeout.
73 * Checking interrupt_callback, looping on EINTR and EAGAIN and until
74 * enough data has been read is left to the calling function; see
75 * retry_transfer_wrapper in avio.c.
77 int (*url_read)( URLContext *h, unsigned char *buf, int size);
78 int (*url_write)(URLContext *h, const unsigned char *buf, int size);
79 int64_t (*url_seek)( URLContext *h, int64_t pos, int whence);
80 int (*url_close)(URLContext *h);
81 int (*url_read_pause)(URLContext *h, int pause);
82 int64_t (*url_read_seek)(URLContext *h, int stream_index,
83 int64_t timestamp, int flags);
84 int (*url_get_file_handle)(URLContext *h);
85 int (*url_get_multi_file_handle)(URLContext *h, int **handles,
87 int (*url_get_short_seek)(URLContext *h);
88 int (*url_shutdown)(URLContext *h, int flags);
89 const AVClass *priv_data_class;
92 int (*url_check)(URLContext *h, int mask);
93 int (*url_open_dir)(URLContext *h);
94 int (*url_read_dir)(URLContext *h, AVIODirEntry **next);
95 int (*url_close_dir)(URLContext *h);
96 int (*url_delete)(URLContext *h);
97 int (*url_move)(URLContext *h_src, URLContext *h_dst);
98 const char *default_whitelist;
102 * Create a URLContext for accessing to the resource indicated by
103 * url, but do not initiate the connection yet.
105 * @param puc pointer to the location where, in case of success, the
106 * function puts the pointer to the created URLContext
107 * @param flags flags which control how the resource indicated by url
109 * @param int_cb interrupt callback to use for the URLContext, may be
111 * @return >= 0 in case of success, a negative value corresponding to an
112 * AVERROR code in case of failure
114 int ffurl_alloc(URLContext **puc, const char *filename, int flags,
115 const AVIOInterruptCB *int_cb);
118 * Connect an URLContext that has been allocated by ffurl_alloc
120 * @param options A dictionary filled with options for nested protocols,
121 * i.e. it will be passed to url_open2() for protocols implementing it.
122 * This parameter will be destroyed and replaced with a dict containing options
123 * that were not found. May be NULL.
125 int ffurl_connect(URLContext *uc, AVDictionary **options);
128 * Create an URLContext for accessing to the resource indicated by
131 * @param puc pointer to the location where, in case of success, the
132 * function puts the pointer to the created URLContext
133 * @param flags flags which control how the resource indicated by url
135 * @param int_cb interrupt callback to use for the URLContext, may be
137 * @param options A dictionary filled with protocol-private options. On return
138 * this parameter will be destroyed and replaced with a dict containing options
139 * that were not found. May be NULL.
140 * @param parent An enclosing URLContext, whose generic options should
141 * be applied to this URLContext as well.
142 * @return >= 0 in case of success, a negative value corresponding to an
143 * AVERROR code in case of failure
145 int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags,
146 const AVIOInterruptCB *int_cb, AVDictionary **options,
147 const char *whitelist, const char* blacklist,
151 * Accept an URLContext c on an URLContext s
153 * @param s server context
154 * @param c client context, must be unallocated.
155 * @return >= 0 on success, ff_neterrno() on failure.
157 int ffurl_accept(URLContext *s, URLContext **c);
160 * Perform one step of the protocol handshake to accept a new client.
161 * See avio_handshake() for details.
162 * Implementations should try to return decreasing values.
163 * If the protocol uses an underlying protocol, the underlying handshake is
164 * usually the first step, and the return value can be:
165 * (largest value for this protocol) + (return value from other protocol)
167 * @param c the client context
168 * @return >= 0 on success or a negative value corresponding
169 * to an AVERROR code on failure
171 int ffurl_handshake(URLContext *c);
173 int ffurl_read2(void *urlcontext, uint8_t *buf, int size);
175 * Read up to size bytes from the resource accessed by h, and store
176 * the read bytes in buf.
178 * @return The number of bytes actually read, or a negative value
179 * corresponding to an AVERROR code in case of error. A value of zero
180 * indicates that it is not possible to read more from the accessed
181 * resource (except if the value of the size argument is also zero).
183 static inline int ffurl_read(URLContext *h, uint8_t *buf, int size)
185 return ffurl_read2(h, buf, size);
189 * Read as many bytes as possible (up to size), calling the
190 * read function multiple times if necessary.
191 * This makes special short-read handling in applications
192 * unnecessary, if the return value is < size then it is
193 * certain there was either an error or the end of file was reached.
195 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size);
197 #if FF_API_AVIO_WRITE_NONCONST
198 int ffurl_write2(void *urlcontext, uint8_t *buf, int size);
200 int ffurl_write2(void *urlcontext, const uint8_t *buf, int size);
203 * Write size bytes from buf to the resource accessed by h.
205 * @return the number of bytes actually written, or a negative value
206 * corresponding to an AVERROR code in case of failure
208 static inline int ffurl_write(URLContext *h, const uint8_t *buf, int size)
210 #if FF_API_AVIO_WRITE_NONCONST
211 return ffurl_write2(h, (uint8_t*)buf, size);
213 return ffurl_write2(h, buf, size);
217 int64_t ffurl_seek2(void *urlcontext, int64_t pos, int whence);
219 * Change the position that will be used by the next read/write
220 * operation on the resource accessed by h.
222 * @param pos specifies the new position to set
223 * @param whence specifies how pos should be interpreted, it must be
224 * one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the
225 * current position), SEEK_END (seek from the end), or AVSEEK_SIZE
226 * (return the filesize of the requested resource, pos is ignored).
227 * @return a negative value corresponding to an AVERROR code in case
228 * of failure, or the resulting file position, measured in bytes from
229 * the beginning of the file. You can use this feature together with
230 * SEEK_CUR to read the current file position.
232 static inline int64_t ffurl_seek(URLContext *h, int64_t pos, int whence)
234 return ffurl_seek2(h, pos, whence);
238 * Close the resource accessed by the URLContext h, and free the
239 * memory used by it. Also set the URLContext pointer to NULL.
241 * @return a negative value if an error condition occurred, 0
244 int ffurl_closep(URLContext **h);
245 int ffurl_close(URLContext *h);
248 * Return the filesize of the resource accessed by h, AVERROR(ENOSYS)
249 * if the operation is not supported by h, or another negative value
250 * corresponding to an AVERROR error code in case of failure.
252 int64_t ffurl_size(URLContext *h);
255 * Return the file descriptor associated with this URL. For RTP, this
256 * will return only the RTP file descriptor, not the RTCP file descriptor.
258 * @return the file descriptor associated with this URL, or <0 on error.
260 int ffurl_get_file_handle(URLContext *h);
263 * Return the file descriptors associated with this URL.
265 * @return 0 on success or <0 on error.
267 int ffurl_get_multi_file_handle(URLContext *h, int **handles, int *numhandles);
270 * Return the current short seek threshold value for this URL.
272 * @return threshold (>0) on success or <=0 on error.
274 int ffurl_get_short_seek(void *urlcontext);
277 * Signal the URLContext that we are done reading or writing the stream.
279 * @param h pointer to the resource
280 * @param flags flags which control how the resource indicated by url
283 * @return a negative value if an error condition occurred, 0
286 int ffurl_shutdown(URLContext *h, int flags);
289 * Check if the user has requested to interrupt a blocking function
290 * associated with cb.
292 int ff_check_interrupt(AVIOInterruptCB *cb);
295 int ff_udp_set_remote_url(URLContext *h, const char *uri);
296 int ff_udp_get_local_port(URLContext *h);
299 * Assemble a URL string from components. This is the reverse operation
302 * Note, this requires networking to be initialized, so the caller must
303 * ensure ff_network_init has been called.
307 * @param str the buffer to fill with the url
308 * @param size the size of the str buffer
309 * @param proto the protocol identifier, if null, the separator
310 * after the identifier is left out, too
311 * @param authorization an optional authorization string, may be null.
312 * An empty string is treated the same as a null string.
313 * @param hostname the host name string
314 * @param port the port number, left out from the string if negative
315 * @param fmt a generic format string for everything to add after the
316 * host/port, may be null
317 * @return the number of characters written to the destination buffer
319 int ff_url_join(char *str, int size, const char *proto,
320 const char *authorization, const char *hostname,
321 int port, const char *fmt, ...) av_printf_format(7, 8);
324 * Convert a relative url into an absolute url, given a base url.
326 * @param buf the buffer where output absolute url is written
327 * @param size the size of buf
328 * @param base the base url, may be equal to buf.
329 * @param rel the new url, which is interpreted relative to base
330 * @param handle_dos_paths handle DOS paths for file or unspecified protocol
332 int ff_make_absolute_url2(char *buf, int size, const char *base,
333 const char *rel, int handle_dos_paths);
336 * Convert a relative url into an absolute url, given a base url.
338 * Same as ff_make_absolute_url2 with handle_dos_paths being equal to
339 * HAVE_DOS_PATHS config variable.
341 int ff_make_absolute_url(char *buf, int size, const char *base,
345 * Allocate directory entry with default values.
347 * @return entry or NULL on error
349 AVIODirEntry *ff_alloc_dir_entry(void);
351 const AVClass *ff_urlcontext_child_class_iterate(void **iter);
354 * Construct a list of protocols matching a given whitelist and/or blacklist.
356 * @param whitelist a comma-separated list of allowed protocol names or NULL. If
357 * this is a non-empty string, only protocols in this list will
359 * @param blacklist a comma-separated list of forbidden protocol names or NULL.
360 * If this is a non-empty string, all protocols in this list
363 * @return a NULL-terminated array of matching protocols. The array must be
364 * freed by the caller.
366 const URLProtocol **ffurl_get_protocols(const char *whitelist,
367 const char *blacklist);
369 typedef struct URLComponents {
370 const char *url; /**< whole URL, for reference */
371 const char *scheme; /**< possibly including lavf-specific options */
372 const char *authority; /**< "//" if it is a real URL */
373 const char *userinfo; /**< including final '@' if present */
375 const char *port; /**< including initial ':' if present */
377 const char *query; /**< including initial '?' if present */
378 const char *fragment; /**< including initial '#' if present */
382 #define url_component_end_scheme authority
383 #define url_component_end_authority userinfo
384 #define url_component_end_userinfo host
385 #define url_component_end_host port
386 #define url_component_end_port path
387 #define url_component_end_path query
388 #define url_component_end_query fragment
389 #define url_component_end_fragment end
390 #define url_component_end_authority_full path
392 #define URL_COMPONENT_HAVE(uc, component) \
393 ((uc).url_component_end_##component > (uc).component)
396 * Parse an URL to find the components.
398 * Each component runs until the start of the next component,
399 * possibly including a mandatory delimiter.
401 * @param uc structure to fill with pointers to the components.
402 * @param url URL to parse.
403 * @param end end of the URL, or NULL to parse to the end of string.
405 * @return >= 0 for success or an AVERROR code, especially if the URL is
408 int ff_url_decompose(URLComponents *uc, const char *url, const char *end);
411 * Move or rename a resource.
413 * @note url_src and url_dst should share the same protocol and authority.
415 * @param url_src url to resource to be moved
416 * @param url_dst new url to resource if the operation succeeded
417 * @return >=0 on success or negative on error.
419 int ffurl_move(const char *url_src, const char *url_dst);
424 * @param url resource to be deleted.
425 * @return >=0 on success or negative on error.
427 int ffurl_delete(const char *url);
429 #endif /* AVFORMAT_URL_H */