libavformat/avio.h

Go to the documentation of this file.

/*
 * copyright (c) 2001 Fabrice Bellard
 *
 * 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
 */
#ifndef AVFORMAT_AVIO_H
#define AVFORMAT_AVIO_H

#include <stdint.h>

#include "libavutil/common.h"
#include "libavutil/dict.h"
#include "libavutil/log.h"

#include "libavformat/version.h"


#define AVIO_SEEKABLE_NORMAL 0x0001 
typedef struct {
    int (*callback)(void*);
    void *opaque;
} AVIOInterruptCB;

typedef struct {
    const AVClass *av_class;
    unsigned char *buffer;  
    int buffer_size;        
    unsigned char *buf_ptr; 
    unsigned char *buf_end; 
    void *opaque;           
    int (*read_packet)(void *opaque, uint8_t *buf, int buf_size);
    int (*write_packet)(void *opaque, uint8_t *buf, int buf_size);
    int64_t (*seek)(void *opaque, int64_t offset, int whence);
    int64_t pos;            
    int must_flush;         
    int eof_reached;        
    int write_flag;         
    int max_packet_size;
    unsigned long checksum;
    unsigned char *checksum_ptr;
    unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size);
    int error;              
    int (*read_pause)(void *opaque, int pause);
    int64_t (*read_seek)(void *opaque, int stream_index,
                         int64_t timestamp, int flags);
    int seekable;

     int64_t maxsize;

     int direct;
} AVIOContext;

/* unbuffered I/O */

int avio_check(const char *url, int flags);

AVIOContext *avio_alloc_context(
                  unsigned char *buffer,
                  int buffer_size,
                  int write_flag,
                  void *opaque,
                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
                  int64_t (*seek)(void *opaque, int64_t offset, int whence));

void avio_w8(AVIOContext *s, int b);
void avio_write(AVIOContext *s, const unsigned char *buf, int size);
void avio_wl64(AVIOContext *s, uint64_t val);
void avio_wb64(AVIOContext *s, uint64_t val);
void avio_wl32(AVIOContext *s, unsigned int val);
void avio_wb32(AVIOContext *s, unsigned int val);
void avio_wl24(AVIOContext *s, unsigned int val);
void avio_wb24(AVIOContext *s, unsigned int val);
void avio_wl16(AVIOContext *s, unsigned int val);
void avio_wb16(AVIOContext *s, unsigned int val);

int avio_put_str(AVIOContext *s, const char *str);

int avio_put_str16le(AVIOContext *s, const char *str);

#define AVSEEK_SIZE 0x10000

#define AVSEEK_FORCE 0x20000

int64_t avio_seek(AVIOContext *s, int64_t offset, int whence);

int64_t avio_skip(AVIOContext *s, int64_t offset);

static av_always_inline int64_t avio_tell(AVIOContext *s)
{
    return avio_seek(s, 0, SEEK_CUR);
}

int64_t avio_size(AVIOContext *s);

int url_feof(AVIOContext *s);

int avio_printf(AVIOContext *s, const char *fmt, ...) av_printf_format(2, 3);

void avio_flush(AVIOContext *s);


int avio_read(AVIOContext *s, unsigned char *buf, int size);

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);
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen);

int avio_get_str16le(AVIOContext *pb, int maxlen, char *buf, int buflen);
int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen);


#define AVIO_FLAG_READ  1                                      
#define AVIO_FLAG_WRITE 2                                      
#define AVIO_FLAG_READ_WRITE (AVIO_FLAG_READ|AVIO_FLAG_WRITE)  
#define AVIO_FLAG_NONBLOCK 8

#define AVIO_FLAG_DIRECT 0x8000

int avio_open(AVIOContext **s, const char *url, int flags);

int avio_open2(AVIOContext **s, const char *url, int flags,
               const AVIOInterruptCB *int_cb, AVDictionary **options);

int avio_close(AVIOContext *s);

int avio_open_dyn_buf(AVIOContext **s);

int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer);

const char *avio_enum_protocols(void **opaque, int output);

int     avio_pause(AVIOContext *h, int pause);

int64_t avio_seek_time(AVIOContext *h, int stream_index,
                       int64_t timestamp, int flags);

#endif /* AVFORMAT_AVIO_H */

---