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/*
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* unbuffered private I/O API
*/
#ifndef AVFORMAT_URL_H
#define AVFORMAT_URL_H
#include "avio.h"
#include "libavformat/version.h"
#include "libavutil/dict.h"
#include "libavutil/log.h"
#define URL_PROTOCOL_FLAG_NESTED_SCHEME 1 /*< The protocol name can be the first part of a nested protocol scheme */
#define URL_PROTOCOL_FLAG_NETWORK 2 /*< The protocol uses network */
extern int (*url_interrupt_cb)(void);
extern const AVClass ffurl_context_class;
typedef struct URLContext {
const AVClass *av_class; /**< information for av_log(). Set by url_open(). */
struct URLProtocol *prot;
void *priv_data;
char *filename; /**< specified URL */
int flags;
int max_packet_size; /**< if non zero, the stream is packetized with this max packet size */
int is_streamed; /**< true if streamed (no seek possible), default = false */
int is_connected;
AVIOInterruptCB interrupt_callback;
} URLContext;
typedef struct URLProtocol {
const char *name;
int (*url_open)( URLContext *h, const char *url, int flags);
/**
* This callback is to be used by protocols which open further nested
* protocols. options are then to be passed to ffurl_open()/ffurl_connect()
* for those nested protocols.
*/
int (*url_open2)(URLContext *h, const char *url, int flags, AVDictionary **options);
/**
* Read data from the protocol.
* If data is immediately available (even less than size), EOF is
* reached or an error occurs (including EINTR), return immediately.
* Otherwise:
* In non-blocking mode, return AVERROR(EAGAIN) immediately.
* In blocking mode, wait for data/EOF/error with a short timeout (0.1s),
* and return AVERROR(EAGAIN) on timeout.
* Checking interrupt_callback, looping on EINTR and EAGAIN and until
* enough data has been read is left to the calling function; see
* retry_transfer_wrapper in avio.c.
*/
int (*url_read)( URLContext *h, unsigned char *buf, int size);
int (*url_write)(URLContext *h, const unsigned char *buf, int size);
int64_t (*url_seek)( URLContext *h, int64_t pos, int whence);
int (*url_close)(URLContext *h);
struct URLProtocol *next;
int (*url_read_pause)(URLContext *h, int pause);
int64_t (*url_read_seek)(URLContext *h, int stream_index,
int64_t timestamp, int flags);
int (*url_get_file_handle)(URLContext *h);
int priv_data_size;
const AVClass *priv_data_class;
int flags;
int (*url_check)(URLContext *h, int mask);
} URLProtocol;
/**
* Create a URLContext for accessing to the resource indicated by
* url, but do not initiate the connection yet.
*
* @param puc pointer to the location where, in case of success, the
* function puts the pointer to the created URLContext
* @param flags flags which control how the resource indicated by url
* is to be opened
* @param int_cb interrupt callback to use for the URLContext, may be
* NULL
* @return 0 in case of success, a negative value corresponding to an
* AVERROR code in case of failure
*/
int ffurl_alloc(URLContext **puc, const char *filename, int flags,
const AVIOInterruptCB *int_cb);
/**
* Connect an URLContext that has been allocated by ffurl_alloc
*
* @param options A dictionary filled with options for nested protocols,
* i.e. it will be passed to url_open2() for protocols implementing it.
* This parameter will be destroyed and replaced with a dict containing options
* that were not found. May be NULL.
*/
int ffurl_connect(URLContext *uc, AVDictionary **options);
/**
* Create an URLContext for accessing to the resource indicated by
* url, and open it.
*
* @param puc pointer to the location where, in case of success, the
* function puts the pointer to the created URLContext
* @param flags flags which control how the resource indicated by url
* is to be opened
* @param int_cb interrupt callback to use for the URLContext, may be
* NULL
* @param options A dictionary filled with protocol-private options. On return
* this parameter will be destroyed and replaced with a dict containing options
* that were not found. May be NULL.
* @return 0 in case of success, a negative value corresponding to an
* AVERROR code in case of failure
*/
int ffurl_open(URLContext **puc, const char *filename, int flags,
const AVIOInterruptCB *int_cb, AVDictionary **options);
/**
* Read up to size bytes from the resource accessed by h, and store
* the read bytes in buf.
*
* @return The number of bytes actually read, or a negative value
* corresponding to an AVERROR code in case of error. A value of zero
* indicates that it is not possible to read more from the accessed
* resource (except if the value of the size argument is also zero).
*/
int ffurl_read(URLContext *h, unsigned char *buf, int size);
/**
* Read as many bytes as possible (up to size), calling the
* read function multiple times if necessary.
* This makes special short-read handling in applications
* unnecessary, if the return value is < size then it is
* certain there was either an error or the end of file was reached.
*/
int ffurl_read_complete(URLContext *h, unsigned char *buf, int size);
/**
* Write size bytes from buf to the resource accessed by h.
*
* @return the number of bytes actually written, or a negative value
* corresponding to an AVERROR code in case of failure
*/
int ffurl_write(URLContext *h, const unsigned char *buf, int size);
/**
* Change the position that will be used by the next read/write
* operation on the resource accessed by h.
*
* @param pos specifies the new position to set
* @param whence specifies how pos should be interpreted, it must be
* one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the
* current position), SEEK_END (seek from the end), or AVSEEK_SIZE
* (return the filesize of the requested resource, pos is ignored).
* @return a negative value corresponding to an AVERROR code in case
* of failure, or the resulting file position, measured in bytes from
* the beginning of the file. You can use this feature together with
* SEEK_CUR to read the current file position.
*/
int64_t ffurl_seek(URLContext *h, int64_t pos, int whence);
/**
* Close the resource accessed by the URLContext h, and free the
* memory used by it.
*
* @return a negative value if an error condition occurred, 0
* otherwise
*/
int ffurl_close(URLContext *h);
/**
* Return the filesize of the resource accessed by h, AVERROR(ENOSYS)
* if the operation is not supported by h, or another negative value
* corresponding to an AVERROR error code in case of failure.
*/
int64_t ffurl_size(URLContext *h);
/**
* Return the file descriptor associated with this URL. For RTP, this
* will return only the RTP file descriptor, not the RTCP file descriptor.
*
* @return the file descriptor associated with this URL, or <0 on error.
*/
int ffurl_get_file_handle(URLContext *h);
/**
* Register the URLProtocol protocol.
*
* @param size the size of the URLProtocol struct referenced
*/
int ffurl_register_protocol(URLProtocol *protocol, int size);
/**
* Check if the user has requested to interrup a blocking function
* associated with cb.
*/
int ff_check_interrupt(AVIOInterruptCB *cb);
/**
* Iterate over all available protocols.
*
* @param prev result of the previous call to this functions or NULL.
*/
URLProtocol *ffurl_protocol_next(URLProtocol *prev);
/* udp.c */
int ff_udp_set_remote_url(URLContext *h, const char *uri);
int ff_udp_get_local_port(URLContext *h);
#endif /* AVFORMAT_URL_H */
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