/*
  *

  * This file is part of FFmpeg.

  *

  * FFmpeg 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.
  *

  * FFmpeg 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 FFmpeg; 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;

     int64_t rw_timeout;         /**< maximum time to wait for (network) read/write operation completion, in mcs */

 } 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 (*url_get_multi_file_handle)(URLContext *h, int **handles,
                                      int *numhandles);

     int (*url_shutdown)(URLContext *h, int flags);

     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. Also set the URLContext pointer to NULL.

  *
  * @return a negative value if an error condition occurred, 0
  * otherwise
  */

 int ffurl_closep(URLContext **h);

 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);
 

 /**

  * Return the file descriptors associated with this URL.
  *
  * @return 0 on success or <0 on error.
  */
 int ffurl_get_multi_file_handle(URLContext *h, int **handles, int *numhandles);
 
 /**

  * Signal the URLContext that we are done reading or writing the stream.
  *
  * @param h pointer to the resource
  * @param flags flags which control how the resource indicated by url
  * is to be shutdown
  *
  * @return a negative value if an error condition occurred, 0
  * otherwise
  */
 int ffurl_shutdown(URLContext *h, int flags);
 
 /**

  * Register the URLProtocol protocol.
  */

 int ffurl_register_protocol(URLProtocol *protocol);

 /**
  * 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(const URLProtocol *prev);

 /* udp.c */
 int ff_udp_set_remote_url(URLContext *h, const char *uri);
 int ff_udp_get_local_port(URLContext *h);
 

 /**
  * Assemble a URL string from components. This is the reverse operation
  * of av_url_split.
  *
  * Note, this requires networking to be initialized, so the caller must
  * ensure ff_network_init has been called.
  *
  * @see av_url_split
  *
  * @param str the buffer to fill with the url
  * @param size the size of the str buffer
  * @param proto the protocol identifier, if null, the separator
  *              after the identifier is left out, too
  * @param authorization an optional authorization string, may be null.
  *                      An empty string is treated the same as a null string.
  * @param hostname the host name string
  * @param port the port number, left out from the string if negative
  * @param fmt a generic format string for everything to add after the
  *            host/port, may be null
  * @return the number of characters written to the destination buffer
  */
 int ff_url_join(char *str, int size, const char *proto,
                 const char *authorization, const char *hostname,
                 int port, const char *fmt, ...) av_printf_format(7, 8);
 

 /**

  * Convert a relative url into an absolute url, given a base url.
  *
  * @param buf the buffer where output absolute url is written
  * @param size the size of buf
  * @param base the base url, may be equal to buf.
  * @param rel the new url, which is interpreted relative to base
  */
 void ff_make_absolute_url(char *buf, int size, const char *base,
                           const char *rel);
 
 

 #endif /* AVFORMAT_URL_H */