21a19b7912
Before this, almost all module groups have been used for grouping functions and fields in structures semantically. This causes them to not appear properly in the file documentation and needlessly clutters up the "Modules" index. Additionally, this commit streamlines some spelling and appearances.
627 lines
24 KiB
C
627 lines
24 KiB
C
/*
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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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* Buffered I/O operations
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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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#define AVIO_SEEKABLE_NORMAL 0x0001 /**< Seeking works like for a local file */
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/**
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* Bytestream IO 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(AVIOContext) must not be used outside libav*.
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*
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* @note None of the function pointers in AVIOContext should be called
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* directly, they should only be set by the client application
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* when implementing custom I/O. Normally these are set to the
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* function pointers specified in avio_alloc_context()
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*/
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typedef struct {
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unsigned char *buffer; /**< Start of the buffer. */
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int buffer_size; /**< Maximum buffer size */
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unsigned char *buf_ptr; /**< Current position in the buffer */
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unsigned char *buf_end; /**< End of the data, may be less than
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buffer+buffer_size if the read function returned
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less data than requested, e.g. for streams where
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no more data has been received yet. */
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void *opaque; /**< A private pointer, passed to the read/write/seek/...
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functions. */
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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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int64_t pos; /**< position in the file of the current buffer */
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int must_flush; /**< true if the next seek should flush */
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int eof_reached; /**< true if eof reached */
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int write_flag; /**< true if open for writing */
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#if FF_API_OLD_AVIO
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attribute_deprecated int is_streamed;
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#endif
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int max_packet_size;
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unsigned long checksum;
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unsigned char *checksum_ptr;
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unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size);
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int error; /**< contains the error code or 0 if no error happened */
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/**
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* Pause or resume playback for network streaming protocols - e.g. MMS.
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*/
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int (*read_pause)(void *opaque, int pause);
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/**
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* Seek to a given timestamp in stream with the specified stream_index.
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* Needed for some network streaming protocols which don't support seeking
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* to byte position.
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*/
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int64_t (*read_seek)(void *opaque, int stream_index,
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int64_t timestamp, int flags);
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/**
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* A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
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*/
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int seekable;
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} AVIOContext;
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/* unbuffered I/O */
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#if FF_API_OLD_AVIO
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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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* @deprecated This struct will be made private
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*/
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typedef struct URLContext {
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const AVClass *av_class; ///< information for av_log(). Set by url_open().
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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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#define URL_PROTOCOL_FLAG_NESTED_SCHEME 1 /*< The protocol name can be the first part of a nested protocol scheme */
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/**
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* @deprecated This struct is to be made private. Use the higher-level
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* AVIOContext-based API instead.
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*/
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typedef struct URLProtocol {
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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;
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int flags;
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int (*url_check)(URLContext *h, int mask);
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} URLProtocol;
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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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/* not implemented */
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attribute_deprecated int url_poll(URLPollEntry *poll_table, int n, int timeout);
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/**
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* @name 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 1 /**< read-only */
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#define URL_WRONLY 2 /**< write-only */
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#define URL_RDWR (URL_RDONLY|URL_WRONLY) /**< 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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extern URLInterruptCB *url_interrupt_cb;
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/**
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* @defgroup old_url_funcs Old url_* functions
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* The following functions are 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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attribute_deprecated int url_alloc(URLContext **h, const char *url, int flags);
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attribute_deprecated int url_connect(URLContext *h);
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attribute_deprecated int url_open(URLContext **h, const char *url, int flags);
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attribute_deprecated int url_read(URLContext *h, unsigned char *buf, int size);
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attribute_deprecated int url_read_complete(URLContext *h, unsigned char *buf, int size);
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attribute_deprecated int url_write(URLContext *h, const unsigned char *buf, int size);
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attribute_deprecated int64_t url_seek(URLContext *h, int64_t pos, int whence);
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attribute_deprecated int url_close(URLContext *h);
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attribute_deprecated int64_t url_filesize(URLContext *h);
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attribute_deprecated int url_get_file_handle(URLContext *h);
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attribute_deprecated int url_get_max_packet_size(URLContext *h);
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attribute_deprecated void url_get_filename(URLContext *h, char *buf, int buf_size);
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attribute_deprecated int av_url_read_pause(URLContext *h, int pause);
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attribute_deprecated int64_t av_url_read_seek(URLContext *h, int stream_index,
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int64_t timestamp, int flags);
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attribute_deprecated void url_set_interrupt_cb(int (*interrupt_cb)(void));
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/**
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* 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,
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* or NULL if protocol is the last one.
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*/
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attribute_deprecated URLProtocol *av_protocol_next(URLProtocol *p);
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/**
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* Register the URLProtocol protocol.
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*
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* @param size the size of the URLProtocol struct referenced
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*/
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attribute_deprecated int av_register_protocol2(URLProtocol *protocol, int size);
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/**
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* @}
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*/
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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,
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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,
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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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/**
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* @defgroup old_avio_funcs Old put_/get_*() functions
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* The following functions are deprecated. Use the "avio_"-prefixed functions instead.
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* @{
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*/
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attribute_deprecated int get_buffer(AVIOContext *s, unsigned char *buf, int size);
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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);
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attribute_deprecated unsigned int get_le32(AVIOContext *s);
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attribute_deprecated uint64_t get_le64(AVIOContext *s);
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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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attribute_deprecated void put_byte(AVIOContext *s, int b);
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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);
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attribute_deprecated void put_be64(AVIOContext *s, uint64_t val);
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attribute_deprecated void put_le32(AVIOContext *s, unsigned int val);
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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);
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attribute_deprecated void put_le16(AVIOContext *s, unsigned int val);
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attribute_deprecated void put_be16(AVIOContext *s, unsigned int val);
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attribute_deprecated void put_tag(AVIOContext *s, const char *tag);
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/**
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* @}
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*/
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attribute_deprecated int av_url_read_fpause(AVIOContext *h, int pause);
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attribute_deprecated int64_t av_url_read_fseek (AVIOContext *h, int stream_index,
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int64_t timestamp, int flags);
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/**
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* @defgroup old_url_f_funcs Old url_f* functions
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* The following functions are deprecated, use the "avio_"-prefixed functions instead.
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* @{
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*/
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attribute_deprecated int url_fopen( AVIOContext **s, const char *url, int flags);
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attribute_deprecated int url_fclose(AVIOContext *s);
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attribute_deprecated int64_t url_fseek(AVIOContext *s, int64_t offset, int whence);
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attribute_deprecated int url_fskip(AVIOContext *s, int64_t offset);
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attribute_deprecated int64_t url_ftell(AVIOContext *s);
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attribute_deprecated int64_t url_fsize(AVIOContext *s);
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#define URL_EOF (-1)
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attribute_deprecated int url_fgetc(AVIOContext *s);
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attribute_deprecated int url_setbufsize(AVIOContext *s, int buf_size);
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attribute_deprecated int url_fprintf(AVIOContext *s, const char *fmt, ...) av_printf_format(2, 3);
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attribute_deprecated void put_flush_packet(AVIOContext *s);
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attribute_deprecated int url_open_dyn_buf(AVIOContext **s);
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attribute_deprecated int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size);
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attribute_deprecated int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer);
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attribute_deprecated int url_fdopen(AVIOContext **s, URLContext *h);
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/**
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* @}
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*/
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/**
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* @deprecated use AVIOContext.eof_reached
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*/
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attribute_deprecated int url_feof(AVIOContext *s);
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attribute_deprecated int url_ferror(AVIOContext *s);
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attribute_deprecated int udp_set_remote_url(URLContext *h, const char *uri);
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attribute_deprecated int udp_get_local_port(URLContext *h);
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attribute_deprecated void init_checksum(AVIOContext *s,
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unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
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unsigned long checksum);
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attribute_deprecated unsigned long get_checksum(AVIOContext *s);
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attribute_deprecated void put_strz(AVIOContext *s, const char *buf);
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/** @note unlike fgets, the EOL character is not returned and a whole
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line is parsed. return NULL if first char read was EOF */
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attribute_deprecated char *url_fgets(AVIOContext *s, char *buf, int buf_size);
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/**
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* @deprecated use avio_get_str instead
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*/
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attribute_deprecated char *get_strz(AVIOContext *s, char *buf, int maxlen);
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/**
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* @deprecated Use AVIOContext.seekable field directly.
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*/
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attribute_deprecated static inline int url_is_streamed(AVIOContext *s)
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{
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return !s->seekable;
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}
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attribute_deprecated URLContext *url_fileno(AVIOContext *s);
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/**
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* @deprecated use AVIOContext.max_packet_size directly.
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*/
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attribute_deprecated int url_fget_max_packet_size(AVIOContext *s);
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attribute_deprecated int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags);
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/** return the written or read size */
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attribute_deprecated int url_close_buf(AVIOContext *s);
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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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* @deprecated Use avio_check instead.
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*/
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attribute_deprecated int url_exist(const char *url);
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#endif // FF_API_OLD_AVIO
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/**
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* Return AVIO_FLAG_* access flags corresponding to the access permissions
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* of the resource in url, or a negative value corresponding to an
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* AVERROR code in case of failure. The returned access flags are
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* masked by the value in flags.
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*
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* @note This function is intrinsically unsafe, in the sense that the
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* checked resource may change its existence or permission status from
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* one call to another. Thus you should not trust the returned value,
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* unless you are sure that no other processes are accessing the
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* checked resource.
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*/
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int avio_check(const char *url, int flags);
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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 avio_set_interrupt_cb(int (*interrupt_cb)(void));
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/**
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* Allocate and initialize an AVIOContext for buffered I/O. It must be later
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* freed with av_free().
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*
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* @param buffer Memory block for input/output operations via AVIOContext.
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* The buffer must be allocated with av_malloc() and friends.
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* @param buffer_size The buffer size is very important for performance.
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* For protocols with fixed blocksize it should be set to this blocksize.
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* For others a typical size is a cache page, e.g. 4kb.
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* @param write_flag Set to 1 if the buffer should be writable, 0 otherwise.
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* @param opaque An opaque pointer to user-specific data.
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* @param read_packet A function for refilling the buffer, may be NULL.
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* @param write_packet A function for writing the buffer contents, may be NULL.
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* @param seek A function for seeking to specified byte position, may be NULL.
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*
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* @return Allocated AVIOContext or NULL on failure.
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*/
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AVIOContext *avio_alloc_context(
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unsigned char *buffer,
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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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void avio_w8(AVIOContext *s, int b);
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void avio_write(AVIOContext *s, const unsigned char *buf, int size);
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void avio_wl64(AVIOContext *s, uint64_t val);
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void avio_wb64(AVIOContext *s, uint64_t val);
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void avio_wl32(AVIOContext *s, unsigned int val);
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void avio_wb32(AVIOContext *s, unsigned int val);
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void avio_wl24(AVIOContext *s, unsigned int val);
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void avio_wb24(AVIOContext *s, unsigned int val);
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void avio_wl16(AVIOContext *s, unsigned int val);
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void avio_wb16(AVIOContext *s, unsigned int val);
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/**
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* Write a NULL-terminated string.
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* @return number of bytes written.
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*/
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int avio_put_str(AVIOContext *s, const char *str);
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/**
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* Convert an UTF-8 string to UTF-16LE and write it.
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* @return number of bytes written.
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*/
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int avio_put_str16le(AVIOContext *s, const char *str);
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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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* 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
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* means that can be extreemly slow.
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* This may be ignored by the seek code.
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*/
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#define AVSEEK_FORCE 0x20000
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/**
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* fseek() equivalent for AVIOContext.
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* @return new position or AVERROR.
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*/
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int64_t avio_seek(AVIOContext *s, int64_t offset, int whence);
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/**
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* Skip given number of bytes forward
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* @return new position or AVERROR.
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*/
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|
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
|
|
{
|
|
return avio_seek(s, offset, SEEK_CUR);
|
|
}
|
|
|
|
/**
|
|
* ftell() equivalent for AVIOContext.
|
|
* @return position or AVERROR.
|
|
*/
|
|
static av_always_inline int64_t avio_tell(AVIOContext *s)
|
|
{
|
|
return avio_seek(s, 0, SEEK_CUR);
|
|
}
|
|
|
|
/**
|
|
* Get the filesize.
|
|
* @return filesize or AVERROR
|
|
*/
|
|
int64_t avio_size(AVIOContext *s);
|
|
|
|
/** @warning currently size is limited */
|
|
int avio_printf(AVIOContext *s, const char *fmt, ...) av_printf_format(2, 3);
|
|
|
|
void avio_flush(AVIOContext *s);
|
|
|
|
|
|
/**
|
|
* Read size bytes from AVIOContext into buf.
|
|
* @return number of bytes read or AVERROR
|
|
*/
|
|
int avio_read(AVIOContext *s, unsigned char *buf, int size);
|
|
|
|
/**
|
|
* @name Functions for reading from AVIOContext
|
|
* @{
|
|
*
|
|
* @note return 0 if EOF, so you cannot use it if EOF handling is
|
|
* necessary
|
|
*/
|
|
int avio_r8 (AVIOContext *s);
|
|
unsigned int avio_rl16(AVIOContext *s);
|
|
unsigned int avio_rl24(AVIOContext *s);
|
|
unsigned int avio_rl32(AVIOContext *s);
|
|
uint64_t avio_rl64(AVIOContext *s);
|
|
unsigned int avio_rb16(AVIOContext *s);
|
|
unsigned int avio_rb24(AVIOContext *s);
|
|
unsigned int avio_rb32(AVIOContext *s);
|
|
uint64_t avio_rb64(AVIOContext *s);
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
/**
|
|
* Read a string from pb into buf. The reading will terminate when either
|
|
* a NULL character was encountered, maxlen bytes have been read, or nothing
|
|
* more can be read from pb. The result is guaranteed to be NULL-terminated, it
|
|
* will be truncated if buf is too small.
|
|
* Note that the string is not interpreted or validated in any way, it
|
|
* might get truncated in the middle of a sequence for multi-byte encodings.
|
|
*
|
|
* @return number of bytes read (is always <= maxlen).
|
|
* If reading ends on EOF or error, the return value will be one more than
|
|
* bytes actually read.
|
|
*/
|
|
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen);
|
|
|
|
/**
|
|
* Read a UTF-16 string from pb and convert it to UTF-8.
|
|
* The reading will terminate when either a null or invalid character was
|
|
* encountered or maxlen bytes have been read.
|
|
* @return number of bytes read (is always <= maxlen)
|
|
*/
|
|
int avio_get_str16le(AVIOContext *pb, int maxlen, char *buf, int buflen);
|
|
int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen);
|
|
|
|
|
|
/**
|
|
* @name URL open modes
|
|
* The flags argument to avio_open must be one of the following
|
|
* constants, optionally ORed with other flags.
|
|
* @{
|
|
*/
|
|
#define AVIO_FLAG_READ 1 /**< read-only */
|
|
#define AVIO_FLAG_WRITE 2 /**< write-only */
|
|
#define AVIO_FLAG_READ_WRITE (AVIO_FLAG_READ|AVIO_FLAG_WRITE) /**< read-write pseudo flag */
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
/**
|
|
* Use non-blocking mode.
|
|
* If this flag is set, operations on the context will return
|
|
* AVERROR(EAGAIN) if they can not be performed immediately.
|
|
* If this flag is not set, operations on the context will never return
|
|
* AVERROR(EAGAIN).
|
|
* Note that this flag does not affect the opening/connecting of the
|
|
* context. Connecting a protocol will always block if necessary (e.g. on
|
|
* network protocols) but never hang (e.g. on busy devices).
|
|
* Warning: non-blocking protocols is work-in-progress; this flag may be
|
|
* silently ignored.
|
|
*/
|
|
#define AVIO_FLAG_NONBLOCK 8
|
|
|
|
/**
|
|
* Create and initialize a AVIOContext for accessing the
|
|
* resource indicated by url.
|
|
* @note When the resource indicated by url has been opened in
|
|
* read+write mode, the AVIOContext can be used only for writing.
|
|
*
|
|
* @param s Used to return the pointer to the created AVIOContext.
|
|
* In case of failure the pointed to value is set to NULL.
|
|
* @param flags flags which control how the resource indicated by url
|
|
* is to be opened
|
|
* @return 0 in case of success, a negative value corresponding to an
|
|
* AVERROR code in case of failure
|
|
*/
|
|
int avio_open(AVIOContext **s, const char *url, int flags);
|
|
|
|
/**
|
|
* Close the resource accessed by the AVIOContext s and free it.
|
|
* This function can only be used if s was opened by avio_open().
|
|
*
|
|
* @return 0 on success, an AVERROR < 0 on error.
|
|
*/
|
|
int avio_close(AVIOContext *s);
|
|
|
|
/**
|
|
* Open a write only memory stream.
|
|
*
|
|
* @param s new IO context
|
|
* @return zero if no error.
|
|
*/
|
|
int avio_open_dyn_buf(AVIOContext **s);
|
|
|
|
/**
|
|
* Return the written size and a pointer to the buffer. The buffer
|
|
* must be freed with av_free().
|
|
* Padding of FF_INPUT_BUFFER_PADDING_SIZE is added to the buffer.
|
|
*
|
|
* @param s IO context
|
|
* @param pbuffer pointer to a byte buffer
|
|
* @return the length of the byte buffer
|
|
*/
|
|
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer);
|
|
|
|
/**
|
|
* Iterate through names of available protocols.
|
|
*
|
|
* @param opaque A private pointer representing current protocol.
|
|
* It must be a pointer to NULL on first iteration and will
|
|
* be updated by successive calls to avio_enum_protocols.
|
|
* @param output If set to 1, iterate over output protocols,
|
|
* otherwise over input protocols.
|
|
*
|
|
* @return A static string containing the name of current protocol or NULL
|
|
*/
|
|
const char *avio_enum_protocols(void **opaque, int output);
|
|
|
|
/**
|
|
* Pause and resume playing - only meaningful if using a network streaming
|
|
* protocol (e.g. MMS).
|
|
* @param pause 1 for pause, 0 for resume
|
|
*/
|
|
int avio_pause(AVIOContext *h, int pause);
|
|
|
|
/**
|
|
* Seek to a given timestamp relative to some component stream.
|
|
* Only meaningful if using a network streaming protocol (e.g. MMS.).
|
|
* @param stream_index The stream index that the timestamp is relative to.
|
|
* If stream_index is (-1) the timestamp should be in AV_TIME_BASE
|
|
* units from the beginning of the presentation.
|
|
* If a stream_index >= 0 is used and the protocol does not support
|
|
* seeking based on component streams, the call will fail with ENOTSUP.
|
|
* @param timestamp timestamp in AVStream.time_base units
|
|
* or if there is no stream specified then in AV_TIME_BASE units.
|
|
* @param flags Optional combination of AVSEEK_FLAG_BACKWARD, AVSEEK_FLAG_BYTE
|
|
* and AVSEEK_FLAG_ANY. The protocol may silently ignore
|
|
* AVSEEK_FLAG_BACKWARD and AVSEEK_FLAG_ANY, but AVSEEK_FLAG_BYTE will
|
|
* fail with ENOTSUP if used and not supported.
|
|
* @return >= 0 on success
|
|
* @see AVInputFormat::read_seek
|
|
*/
|
|
int64_t avio_seek_time(AVIOContext *h, int stream_index,
|
|
int64_t timestamp, int flags);
|
|
|
|
#endif /* AVFORMAT_AVIO_H */
|