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/*
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 * copyright (c) 2001 Fabrice Bellard
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 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVFORMAT_AVIO_H
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#define AVFORMAT_AVIO_H
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/**
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 * @file
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 * unbuffered I/O operations
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 *
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 * @warning This file has to be considered an internal but installed
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 * header, so it should not be directly included in your projects.
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 */
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#include <stdint.h>
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#include "libavutil/common.h"
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#include "libavutil/log.h"
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#include "libavformat/version.h"
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/* unbuffered I/O */
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/**
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 * URL Context.
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 * New fields can be added to the end with minor version bumps.
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 * Removal, reordering and changes to existing fields require a major
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 * version bump.
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 * sizeof(URLContext) must not be used outside libav*.
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 */
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typedef struct URLContext {
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#if FF_API_URL_CLASS
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    const AVClass *av_class; ///< information for av_log(). Set by url_open().
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#endif
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    struct URLProtocol *prot;
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    int flags;
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    int is_streamed;  /**< true if streamed (no seek possible), default = false */
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    int max_packet_size;  /**< if non zero, the stream is packetized with this max packet size */
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    void *priv_data;
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    char *filename; /**< specified URL */
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    int is_connected;
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} URLContext;
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#if FF_API_OLD_AVIO
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typedef struct URLPollEntry {
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    URLContext *handle;
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    int events;
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    int revents;
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} URLPollEntry;
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#endif
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/**
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 * @defgroup open_modes URL open modes
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 * The flags argument to url_open and cosins must be one of the following
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 * constants, optionally ORed with other flags.
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 * @{
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 */
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#define URL_RDONLY 0  /**< read-only */
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#define URL_WRONLY 1  /**< write-only */
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#define URL_RDWR   2  /**< read-write */
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/**
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 * @}
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 */
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/**
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 * Use non-blocking mode.
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 * If this flag is set, operations on the context will return
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 * AVERROR(EAGAIN) if they can not be performed immediately.
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 * If this flag is not set, operations on the context will never return
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 * AVERROR(EAGAIN).
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 * Note that this flag does not affect the opening/connecting of the
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 * context. Connecting a protocol will always block if necessary (e.g. on
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 * network protocols) but never hang (e.g. on busy devices).
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 * Warning: non-blocking protocols is work-in-progress; this flag may be
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 * silently ignored.
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 */
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#define URL_FLAG_NONBLOCK 4
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typedef int URLInterruptCB(void);
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#if FF_API_OLD_AVIO
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/**
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 * @defgroup old_url_funcs Old url_* functions
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 * @deprecated use the buffered API based on AVIOContext instead
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 * @{
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 */
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attribute_deprecated int url_open_protocol (URLContext **puc, struct URLProtocol *up,
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                                            const char *url, int flags);
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#endif
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/**
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 * Create a URLContext for accessing to the resource indicated by
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 * url, but do not initiate the connection yet.
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 *
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 * @param puc pointer to the location where, in case of success, the
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 * function puts the pointer to the created URLContext
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 * @param flags flags which control how the resource indicated by url
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 * is to be opened
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 * @return 0 in case of success, a negative value corresponding to an
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 * AVERROR code in case of failure
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 */
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int url_alloc(URLContext **h, const char *url, int flags);
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/**
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 * Connect an URLContext that has been allocated by url_alloc
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 */
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int url_connect(URLContext *h);
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/**
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 * Create an URLContext for accessing to the resource indicated by
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 * url, and open it.
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 *
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 * @param puc pointer to the location where, in case of success, the
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 * function puts the pointer to the created URLContext
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 * @param flags flags which control how the resource indicated by url
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 * is to be opened
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 * @return 0 in case of success, a negative value corresponding to an
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 * AVERROR code in case of failure
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 */
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int url_open(URLContext **h, const char *url, int flags);
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/**
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 * Read up to size bytes from the resource accessed by h, and store
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 * the read bytes in buf.
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 *
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 * @return The number of bytes actually read, or a negative value
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 * corresponding to an AVERROR code in case of error. A value of zero
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 * indicates that it is not possible to read more from the accessed
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 * resource (except if the value of the size argument is also zero).
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 */
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int url_read(URLContext *h, unsigned char *buf, int size);
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/**
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 * Read as many bytes as possible (up to size), calling the
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 * read function multiple times if necessary.
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 * This makes special short-read handling in applications
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 * unnecessary, if the return value is < size then it is
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 * certain there was either an error or the end of file was reached.
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 */
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int url_read_complete(URLContext *h, unsigned char *buf, int size);
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/**
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 * Write size bytes from buf to the resource accessed by h.
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 *
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 * @return the number of bytes actually written, or a negative value
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 * corresponding to an AVERROR code in case of failure
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 */
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int url_write(URLContext *h, const unsigned char *buf, int size);
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/**
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 * Passing this as the "whence" parameter to a seek function causes it to
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 * return the filesize without seeking anywhere. Supporting this is optional.
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 * If it is not supported then the seek function will return <0.
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 */
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#define AVSEEK_SIZE 0x10000
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/**
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 * Change the position that will be used by the next read/write
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 * operation on the resource accessed by h.
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 *
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 * @param pos specifies the new position to set
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 * @param whence specifies how pos should be interpreted, it must be
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 * one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the
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 * current position), SEEK_END (seek from the end), or AVSEEK_SIZE
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 * (return the filesize of the requested resource, pos is ignored).
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 * @return a negative value corresponding to an AVERROR code in case
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 * of failure, or the resulting file position, measured in bytes from
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 * the beginning of the file. You can use this feature together with
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 * SEEK_CUR to read the current file position.
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 */
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int64_t url_seek(URLContext *h, int64_t pos, int whence);
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/**
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 * Close the resource accessed by the URLContext h, and free the
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 * memory used by it.
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 *
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 * @return a negative value if an error condition occurred, 0
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 * otherwise
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 */
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int url_close(URLContext *h);
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/**
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 * Return a non-zero value if the resource indicated by url
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 * exists, 0 otherwise.
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 */
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int url_exist(const char *url);
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/**
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 * Return the filesize of the resource accessed by h, AVERROR(ENOSYS)
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 * if the operation is not supported by h, or another negative value
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 * corresponding to an AVERROR error code in case of failure.
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 */
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int64_t url_filesize(URLContext *h);
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/**
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 * Return the file descriptor associated with this URL. For RTP, this
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 * will return only the RTP file descriptor, not the RTCP file descriptor.
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 *
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 * @return the file descriptor associated with this URL, or <0 on error.
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 */
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int url_get_file_handle(URLContext *h);
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/**
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 * Return the maximum packet size associated to packetized file
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 * handle. If the file is not packetized (stream like HTTP or file on
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 * disk), then 0 is returned.
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 *
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 * @param h file handle
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 * @return maximum packet size in bytes
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 */
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int url_get_max_packet_size(URLContext *h);
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/**
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 * Copy the filename of the resource accessed by h to buf.
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 *
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 * @param buf_size size in bytes of buf
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 */
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void url_get_filename(URLContext *h, char *buf, int buf_size);
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/**
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 * The callback is called in blocking functions to test regulary if
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 * asynchronous interruption is needed. AVERROR_EXIT is returned
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 * in this case by the interrupted function. 'NULL' means no interrupt
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 * callback is given.
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 */
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void url_set_interrupt_cb(URLInterruptCB *interrupt_cb);
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#if FF_API_OLD_AVIO
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/* not implemented */
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attribute_deprecated int url_poll(URLPollEntry *poll_table, int n, int timeout);
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#endif
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/**
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 * Pause and resume playing - only meaningful if using a network streaming
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 * protocol (e.g. MMS).
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 * @param pause 1 for pause, 0 for resume
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 */
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int av_url_read_pause(URLContext *h, int pause);
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/**
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 * Seek to a given timestamp relative to some component stream.
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 * Only meaningful if using a network streaming protocol (e.g. MMS.).
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 * @param stream_index The stream index that the timestamp is relative to.
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 *        If stream_index is (-1) the timestamp should be in AV_TIME_BASE
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 *        units from the beginning of the presentation.
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 *        If a stream_index >= 0 is used and the protocol does not support
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 *        seeking based on component streams, the call will fail with ENOTSUP.
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 * @param timestamp timestamp in AVStream.time_base units
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 *        or if there is no stream specified then in AV_TIME_BASE units.
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 * @param flags Optional combination of AVSEEK_FLAG_BACKWARD, AVSEEK_FLAG_BYTE
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 *        and AVSEEK_FLAG_ANY. The protocol may silently ignore
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 *        AVSEEK_FLAG_BACKWARD and AVSEEK_FLAG_ANY, but AVSEEK_FLAG_BYTE will
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 *        fail with ENOTSUP if used and not supported.
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 * @return >= 0 on success
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 * @see AVInputFormat::read_seek
272
 */
273
int64_t av_url_read_seek(URLContext *h, int stream_index,
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                         int64_t timestamp, int flags);
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276
/**
277
 * Oring this flag as into the "whence" parameter to a seek function causes it to
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 * seek by any means (like reopening and linear reading) or other normally unreasonble
279
 * means that can be extreemly slow.
280
 * This may be ignored by the seek code.
281
 */
282
#define AVSEEK_FORCE 0x20000
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284
#define URL_PROTOCOL_FLAG_NESTED_SCHEME 1 /*< The protocol name can be the first part of a nested protocol scheme */
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286
typedef struct URLProtocol {
287
    const char *name;
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    int (*url_open)(URLContext *h, const char *url, int flags);
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    int (*url_read)(URLContext *h, unsigned char *buf, int size);
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    int (*url_write)(URLContext *h, const unsigned char *buf, int size);
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    int64_t (*url_seek)(URLContext *h, int64_t pos, int whence);
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    int (*url_close)(URLContext *h);
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    struct URLProtocol *next;
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    int (*url_read_pause)(URLContext *h, int pause);
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    int64_t (*url_read_seek)(URLContext *h, int stream_index,
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                             int64_t timestamp, int flags);
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    int (*url_get_file_handle)(URLContext *h);
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    int priv_data_size;
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    const AVClass *priv_data_class;
300
    int flags;
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} URLProtocol;
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#if FF_API_REGISTER_PROTOCOL
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extern URLProtocol *first_protocol;
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#endif
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extern URLInterruptCB *url_interrupt_cb;
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309
/**
310
 * If protocol is NULL, returns the first registered protocol,
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 * if protocol is non-NULL, returns the next registered protocol after protocol,
312
 * or NULL if protocol is the last one.
313
 */
314
URLProtocol *av_protocol_next(URLProtocol *p);
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316
#if FF_API_REGISTER_PROTOCOL
317
/**
318
 * @deprecated Use av_register_protocol() instead.
319
 */
320
attribute_deprecated int register_protocol(URLProtocol *protocol);
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322
/**
323
 * @deprecated Use av_register_protocol2() instead.
324
 */
325
attribute_deprecated int av_register_protocol(URLProtocol *protocol);
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#endif
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328
/**
329
 * Register the URLProtocol protocol.
330
 *
331
 * @param size the size of the URLProtocol struct referenced
332
 */
333
int av_register_protocol2(URLProtocol *protocol, int size);
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335
#define AVIO_SEEKABLE_NORMAL 0x0001 /**< Seeking works like for a local file */
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337
/**
338
 * @}
339
 */
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341
/**
342
 * Bytestream IO Context.
343
 * New fields can be added to the end with minor version bumps.
344
 * Removal, reordering and changes to existing fields require a major
345
 * version bump.
346
 * sizeof(AVIOContext) must not be used outside libav*.
347
 */
348
typedef struct {
349
    unsigned char *buffer;
350
    int buffer_size;
351
    unsigned char *buf_ptr, *buf_end;
352
    void *opaque;
353
    int (*read_packet)(void *opaque, uint8_t *buf, int buf_size);
354
    int (*write_packet)(void *opaque, uint8_t *buf, int buf_size);
355
    int64_t (*seek)(void *opaque, int64_t offset, int whence);
356
    int64_t pos; /**< position in the file of the current buffer */
357
    int must_flush; /**< true if the next seek should flush */
358
    int eof_reached; /**< true if eof reached */
359
    int write_flag;  /**< true if open for writing */
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#if FF_API_OLD_AVIO
361
    attribute_deprecated int is_streamed;
362
#endif
363
    int max_packet_size;
364
    unsigned long checksum;
365
    unsigned char *checksum_ptr;
366
    unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size);
367
    int error;         ///< contains the error code or 0 if no error happened
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    int (*read_pause)(void *opaque, int pause);
369
    int64_t (*read_seek)(void *opaque, int stream_index,
370
                         int64_t timestamp, int flags);
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    /**
372
     * A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
373
     */
374
    int seekable;
375
} AVIOContext;
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#if FF_API_OLD_AVIO
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typedef attribute_deprecated AVIOContext ByteIOContext;
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attribute_deprecated int init_put_byte(AVIOContext *s,
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                  unsigned char *buffer,
382
                  int buffer_size,
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                  int write_flag,
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                  void *opaque,
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                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
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                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
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                  int64_t (*seek)(void *opaque, int64_t offset, int whence));
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attribute_deprecated AVIOContext *av_alloc_put_byte(
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                  unsigned char *buffer,
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                  int buffer_size,
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                  int write_flag,
392
                  void *opaque,
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                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
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                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
395
                  int64_t (*seek)(void *opaque, int64_t offset, int whence));
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/**
398
 * @defgroup old_avio_funcs Old put_/get_*() functions
399
 * @deprecated use the avio_ -prefixed functions instead.
400
 * @{
401
 */
402
attribute_deprecated int          get_buffer(AVIOContext *s, unsigned char *buf, int size);
403
attribute_deprecated int          get_partial_buffer(AVIOContext *s, unsigned char *buf, int size);
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attribute_deprecated int          get_byte(AVIOContext *s);
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attribute_deprecated unsigned int get_le16(AVIOContext *s);
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attribute_deprecated unsigned int get_le24(AVIOContext *s);
407
attribute_deprecated unsigned int get_le32(AVIOContext *s);
408
attribute_deprecated uint64_t     get_le64(AVIOContext *s);
409
attribute_deprecated unsigned int get_be16(AVIOContext *s);
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attribute_deprecated unsigned int get_be24(AVIOContext *s);
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attribute_deprecated unsigned int get_be32(AVIOContext *s);
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attribute_deprecated uint64_t     get_be64(AVIOContext *s);
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414
attribute_deprecated void         put_byte(AVIOContext *s, int b);
415
attribute_deprecated void         put_nbyte(AVIOContext *s, int b, int count);
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attribute_deprecated void         put_buffer(AVIOContext *s, const unsigned char *buf, int size);
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attribute_deprecated void         put_le64(AVIOContext *s, uint64_t val);
418
attribute_deprecated void         put_be64(AVIOContext *s, uint64_t val);
419
attribute_deprecated void         put_le32(AVIOContext *s, unsigned int val);
420
attribute_deprecated void         put_be32(AVIOContext *s, unsigned int val);
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attribute_deprecated void         put_le24(AVIOContext *s, unsigned int val);
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attribute_deprecated void         put_be24(AVIOContext *s, unsigned int val);
423
attribute_deprecated void         put_le16(AVIOContext *s, unsigned int val);
424
attribute_deprecated void         put_be16(AVIOContext *s, unsigned int val);
425
attribute_deprecated void         put_tag(AVIOContext *s, const char *tag);
426
/**
427
 * @}
428
 */
429

    
430
attribute_deprecated int     av_url_read_fpause(AVIOContext *h,    int pause);
431
attribute_deprecated int64_t av_url_read_fseek (AVIOContext *h,    int stream_index,
432
                                                int64_t timestamp, int flags);
433

    
434
/**
435
 * @defgroup old_url_f_funcs Old url_f* functions
436
 * @deprecated use the avio_ -prefixed functions instead.
437
 * @{
438
 */
439
attribute_deprecated int url_fopen( AVIOContext **s, const char *url, int flags);
440
attribute_deprecated int url_fclose(AVIOContext *s);
441
attribute_deprecated int64_t url_fseek(AVIOContext *s, int64_t offset, int whence);
442
attribute_deprecated int url_fskip(AVIOContext *s, int64_t offset);
443
attribute_deprecated int64_t url_ftell(AVIOContext *s);
444
attribute_deprecated int64_t url_fsize(AVIOContext *s);
445
#define URL_EOF (-1)
446
attribute_deprecated int url_fgetc(AVIOContext *s);
447
attribute_deprecated int url_setbufsize(AVIOContext *s, int buf_size);
448
#ifdef __GNUC__
449
attribute_deprecated int url_fprintf(AVIOContext *s, const char *fmt, ...) __attribute__ ((__format__ (__printf__, 2, 3)));
450
#else
451
attribute_deprecated int url_fprintf(AVIOContext *s, const char *fmt, ...);
452
#endif
453
attribute_deprecated void put_flush_packet(AVIOContext *s);
454
attribute_deprecated int url_open_dyn_buf(AVIOContext **s);
455
attribute_deprecated int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size);
456
attribute_deprecated int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer);
457
attribute_deprecated int url_fdopen(AVIOContext **s, URLContext *h);
458
/**
459
 * @}
460
 */
461

    
462
/**
463
 * @deprecated use AVIOContext.eof_reached
464
 */
465
attribute_deprecated int url_feof(AVIOContext *s);
466
attribute_deprecated int url_ferror(AVIOContext *s);
467

    
468
attribute_deprecated int udp_set_remote_url(URLContext *h, const char *uri);
469
attribute_deprecated int udp_get_local_port(URLContext *h);
470

    
471
attribute_deprecated void init_checksum(AVIOContext *s,
472
                   unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
473
                   unsigned long checksum);
474
attribute_deprecated unsigned long get_checksum(AVIOContext *s);
475
#endif
476

    
477
/**
478
 * Allocate and initialize an AVIOContext for buffered I/O. It must be later
479
 * freed with av_free().
480
 *
481
 * @param buffer Memory block for input/output operations via AVIOContext.
482
 * @param buffer_size The buffer size is very important for performance.
483
 *        For protocols with fixed blocksize it should be set to this blocksize.
484
 *        For others a typical size is a cache page, e.g. 4kb.
485
 * @param write_flag Set to 1 if the buffer should be writable, 0 otherwise.
486
 * @param opaque An opaque pointer to user-specific data.
487
 * @param read_packet  A function for refilling the buffer, may be NULL.
488
 * @param write_packet A function for writing the buffer contents, may be NULL.
489
 * @param seek A function for seeking to specified byte position, may be NULL.
490
 *
491
 * @return Allocated AVIOContext or NULL on failure.
492
 */
493
AVIOContext *avio_alloc_context(
494
                  unsigned char *buffer,
495
                  int buffer_size,
496
                  int write_flag,
497
                  void *opaque,
498
                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
499
                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
500
                  int64_t (*seek)(void *opaque, int64_t offset, int whence));
501

    
502
void avio_w8(AVIOContext *s, int b);
503
void avio_write(AVIOContext *s, const unsigned char *buf, int size);
504
void avio_wl64(AVIOContext *s, uint64_t val);
505
void avio_wb64(AVIOContext *s, uint64_t val);
506
void avio_wl32(AVIOContext *s, unsigned int val);
507
void avio_wb32(AVIOContext *s, unsigned int val);
508
void avio_wl24(AVIOContext *s, unsigned int val);
509
void avio_wb24(AVIOContext *s, unsigned int val);
510
void avio_wl16(AVIOContext *s, unsigned int val);
511
void avio_wb16(AVIOContext *s, unsigned int val);
512

    
513
#if FF_API_OLD_AVIO
514
attribute_deprecated void put_strz(AVIOContext *s, const char *buf);
515
#endif
516

    
517
/**
518
 * Write a NULL-terminated string.
519
 * @return number of bytes written.
520
 */
521
int avio_put_str(AVIOContext *s, const char *str);
522

    
523
/**
524
 * Convert an UTF-8 string to UTF-16LE and write it.
525
 * @return number of bytes written.
526
 */
527
int avio_put_str16le(AVIOContext *s, const char *str);
528

    
529
/**
530
 * fseek() equivalent for AVIOContext.
531
 * @return new position or AVERROR.
532
 */
533
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence);
534

    
535
/**
536
 * Skip given number of bytes forward
537
 * @return new position or AVERROR.
538
 */
539
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
540
{
541
    return avio_seek(s, offset, SEEK_CUR);
542
}
543

    
544
/**
545
 * ftell() equivalent for AVIOContext.
546
 * @return position or AVERROR.
547
 */
548
static av_always_inline int64_t avio_tell(AVIOContext *s)
549
{
550
    return avio_seek(s, 0, SEEK_CUR);
551
}
552

    
553
/**
554
 * Get the filesize.
555
 * @return filesize or AVERROR
556
 */
557
int64_t avio_size(AVIOContext *s);
558

    
559
/** @warning currently size is limited */
560
#ifdef __GNUC__
561
int avio_printf(AVIOContext *s, const char *fmt, ...) __attribute__ ((__format__ (__printf__, 2, 3)));
562
#else
563
int avio_printf(AVIOContext *s, const char *fmt, ...);
564
#endif
565

    
566
#if FF_API_OLD_AVIO
567
/** @note unlike fgets, the EOL character is not returned and a whole
568
    line is parsed. return NULL if first char read was EOF */
569
attribute_deprecated char *url_fgets(AVIOContext *s, char *buf, int buf_size);
570
#endif
571

    
572
void avio_flush(AVIOContext *s);
573

    
574

    
575
/**
576
 * Read size bytes from AVIOContext into buf.
577
 * @return number of bytes read or AVERROR
578
 */
579
int avio_read(AVIOContext *s, unsigned char *buf, int size);
580

    
581
/** @note return 0 if EOF, so you cannot use it if EOF handling is
582
    necessary */
583
int          avio_r8  (AVIOContext *s);
584
unsigned int avio_rl16(AVIOContext *s);
585
unsigned int avio_rl24(AVIOContext *s);
586
unsigned int avio_rl32(AVIOContext *s);
587
uint64_t     avio_rl64(AVIOContext *s);
588

    
589
/**
590
 * Read a string from pb into buf. The reading will terminate when either
591
 * a NULL character was encountered, maxlen bytes have been read, or nothing
592
 * more can be read from pb. The result is guaranteed to be NULL-terminated, it
593
 * will be truncated if buf is too small.
594
 * Note that the string is not interpreted or validated in any way, it
595
 * might get truncated in the middle of a sequence for multi-byte encodings.
596
 *
597
 * @return number of bytes read (is always <= maxlen).
598
 * If reading ends on EOF or error, the return value will be one more than
599
 * bytes actually read.
600
 */
601
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen);
602

    
603
/**
604
 * Read a UTF-16 string from pb and convert it to UTF-8.
605
 * The reading will terminate when either a null or invalid character was
606
 * encountered or maxlen bytes have been read.
607
 * @return number of bytes read (is always <= maxlen)
608
 */
609
int avio_get_str16le(AVIOContext *pb, int maxlen, char *buf, int buflen);
610
int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen);
611

    
612
#if FF_API_OLD_AVIO
613
/**
614
 * @deprecated use avio_get_str instead
615
 */
616
attribute_deprecated char *get_strz(AVIOContext *s, char *buf, int maxlen);
617
#endif
618
unsigned int avio_rb16(AVIOContext *s);
619
unsigned int avio_rb24(AVIOContext *s);
620
unsigned int avio_rb32(AVIOContext *s);
621
uint64_t     avio_rb64(AVIOContext *s);
622

    
623
#if FF_API_OLD_AVIO
624
/**
625
 * @deprecated Use AVIOContext.seekable field directly.
626
 */
627
attribute_deprecated static inline int url_is_streamed(AVIOContext *s)
628
{
629
    return !s->seekable;
630
}
631
#endif
632

    
633
#if FF_API_URL_RESETBUF
634
/** Reset the buffer for reading or writing.
635
 * @note Will drop any data currently in the buffer without transmitting it.
636
 * @param flags URL_RDONLY to set up the buffer for reading, or URL_WRONLY
637
 *        to set up the buffer for writing. */
638
int url_resetbuf(AVIOContext *s, int flags);
639
#endif
640

    
641
/**
642
 * Create and initialize a AVIOContext for accessing the
643
 * resource indicated by url.
644
 * @note When the resource indicated by url has been opened in
645
 * read+write mode, the AVIOContext can be used only for writing.
646
 *
647
 * @param s Used to return the pointer to the created AVIOContext.
648
 * In case of failure the pointed to value is set to NULL.
649
 * @param flags flags which control how the resource indicated by url
650
 * is to be opened
651
 * @return 0 in case of success, a negative value corresponding to an
652
 * AVERROR code in case of failure
653
 */
654
int avio_open(AVIOContext **s, const char *url, int flags);
655

    
656
int avio_close(AVIOContext *s);
657

    
658
#if FF_API_OLD_AVIO
659
attribute_deprecated URLContext *url_fileno(AVIOContext *s);
660

    
661
/**
662
 * @deprecated use AVIOContext.max_packet_size directly.
663
 */
664
attribute_deprecated int url_fget_max_packet_size(AVIOContext *s);
665

    
666
attribute_deprecated int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags);
667

    
668
/** return the written or read size */
669
attribute_deprecated int url_close_buf(AVIOContext *s);
670
#endif
671

    
672
/**
673
 * Open a write only memory stream.
674
 *
675
 * @param s new IO context
676
 * @return zero if no error.
677
 */
678
int avio_open_dyn_buf(AVIOContext **s);
679

    
680
/**
681
 * Return the written size and a pointer to the buffer. The buffer
682
 * must be freed with av_free().
683
 * Padding of FF_INPUT_BUFFER_PADDING_SIZE is added to the buffer.
684
 *
685
 * @param s IO context
686
 * @param pbuffer pointer to a byte buffer
687
 * @return the length of the byte buffer
688
 */
689
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer);
690

    
691
#if FF_API_UDP_GET_FILE
692
int udp_get_file_handle(URLContext *h);
693
#endif
694

    
695
#endif /* AVFORMAT_AVIO_H */