avio.h

См. документацию.

/*
 * 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 (1 << 0)
 
#define AVIO_SEEKABLE_TIME   (1 << 1)
 
typedef struct AVIOInterruptCB {
    int (*callback)(void*);
    void *opaque;
} AVIOInterruptCB;
 
enum AVIODirEntryType {
    AVIO_ENTRY_UNKNOWN,
    AVIO_ENTRY_BLOCK_DEVICE,
    AVIO_ENTRY_CHARACTER_DEVICE,
    AVIO_ENTRY_DIRECTORY,
    AVIO_ENTRY_NAMED_PIPE,
    AVIO_ENTRY_SYMBOLIC_LINK,
    AVIO_ENTRY_SOCKET,
    AVIO_ENTRY_FILE,
    AVIO_ENTRY_SERVER,
    AVIO_ENTRY_SHARE,
    AVIO_ENTRY_WORKGROUP,
};
 
typedef struct AVIODirEntry {
    char *name;                           
    int type;                             
    int utf8;                             
    int64_t size;                         
    int64_t modification_timestamp;       
    int64_t access_timestamp;             
    int64_t status_change_timestamp;      
    int64_t user_id;                      
    int64_t group_id;                     
    int64_t filemode;                     
} AVIODirEntry;
 
typedef struct AVIODirContext {
    struct URLContext *url_context;
} AVIODirContext;
 
enum AVIODataMarkerType {
    AVIO_DATA_MARKER_HEADER,
    AVIO_DATA_MARKER_SYNC_POINT,
    AVIO_DATA_MARKER_BOUNDARY_POINT,
    AVIO_DATA_MARKER_UNKNOWN,
    AVIO_DATA_MARKER_TRAILER,
    AVIO_DATA_MARKER_FLUSH_POINT,
};
 
typedef struct AVIOContext {
    const AVClass *av_class;
 
    /*
     * The following shows the relationship between buffer, buf_ptr,
     * buf_ptr_max, buf_end, buf_size, and pos, when reading and when writing
     * (since AVIOContext is used for both):
     *
     **********************************************************************************
     *                                   READING
     **********************************************************************************
     *
     *                            |              buffer_size              |
     *                            |---------------------------------------|
     *                            |                                       |
     *
     *                         buffer          buf_ptr       buf_end
     *                            +---------------+-----------------------+
     *                            |/ / / / / / / /|/ / / / / / /|         |
     *  read buffer:              |/ / consumed / | to be read /|         |
     *                            |/ / / / / / / /|/ / / / / / /|         |
     *                            +---------------+-----------------------+
     *
     *                                                         pos
     *              +-------------------------------------------+-----------------+
     *  input file: |                                           |                 |
     *              +-------------------------------------------+-----------------+
     *
     *
     **********************************************************************************
     *                                   WRITING
     **********************************************************************************
     *
     *                             |          buffer_size                 |
     *                             |--------------------------------------|
     *                             |                                      |
     *
     *                                                buf_ptr_max
     *                          buffer                 (buf_ptr)       buf_end
     *                             +-----------------------+--------------+
     *                             |/ / / / / / / / / / / /|              |
     *  write buffer:              | / / to be flushed / / |              |
     *                             |/ / / / / / / / / / / /|              |
     *                             +-----------------------+--------------+
     *                               buf_ptr can be in this
     *                               due to a backward seek
     *
     *                            pos
     *               +-------------+----------------------------------------------+
     *  output file: |             |                                              |
     *               +-------------+----------------------------------------------+
     *
     */
    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 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;
 
    int64_t bytes_read;
 
    int seek_count;
 
    int writeout_count;
 
    int orig_buffer_size;
 
    int short_seek_threshold;
 
    const char *protocol_whitelist;
 
    const char *protocol_blacklist;
 
    int (*write_data_type)(void *opaque, uint8_t *buf, int buf_size,
                           enum AVIODataMarkerType type, int64_t time);
    int ignore_boundary_point;
 
    enum AVIODataMarkerType current_type;
    int64_t last_time;
 
    int (*short_seek_get)(void *opaque);
 
    int64_t written;
 
    unsigned char *buf_ptr_max;
 
    int min_packet_size;
} AVIOContext;
 
const char *avio_find_protocol_name(const char *url);
 
int avio_check(const char *url, int flags);
 
int avpriv_io_move(const char *url_src, const char *url_dst);
 
int avpriv_io_delete(const char *url);
 
int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options);
 
int avio_read_dir(AVIODirContext *s, AVIODirEntry **next);
 
int avio_close_dir(AVIODirContext **s);
 
void avio_free_directory_entry(AVIODirEntry **entry);
 
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_context_free(AVIOContext **s);
 
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);
 
int avio_put_str16be(AVIOContext *s, const char *str);
 
void avio_write_marker(AVIOContext *s, int64_t time, enum AVIODataMarkerType type);
 
#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 avio_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_read_partial(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_closep(AVIOContext **s);
 
 
int avio_open_dyn_buf(AVIOContext **s);
 
int avio_get_dyn_buf(AVIOContext *s, uint8_t **pbuffer);
 
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);
 
/* Avoid a warning. The header can not be included because it breaks c++. */
struct AVBPrint;
 
int avio_read_to_bprint(AVIOContext *h, struct AVBPrint *pb, size_t max_size);
 
int avio_accept(AVIOContext *s, AVIOContext **c);
 
int avio_handshake(AVIOContext *c);
#endif /* AVFORMAT_AVIO_H */