ffmpeg_develop_doc/ffplay源码和书籍/ffplay/libavformat/avio.h

#ifndef AVIO_H
#define AVIO_H

/*
** <EFBFBD>ļ<EFBFBD><EFBFBD><EFBFBD>дģ<EFBFBD>鶨<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݽṹ<EFBFBD>ͺ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
*/

#define URL_EOF (-1)

typedef int64_t offset_t;

/* <EFBFBD>ļ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD>Ȩ<EFBFBD>޵Ķ<EFBFBD><EFBFBD><EFBFBD> */
#define URL_RDONLY 0
#define URL_WRONLY 1
#define URL_RDWR   2

/* 
** URL<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ģ<EFBFBD><EFBFBD><EFBFBD>ʾһ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>루<EFBFBD>ļ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>׽<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD>
** URLContext <EFBFBD>ṹ<EFBFBD><EFBFBD>ʾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>еĵ<EFBFBD>ǰ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD>Э<EFBFBD><EFBFBD>ʹ<EFBFBD>õ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ģ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>й<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD>Э<EFBFBD>鹲<EFBFBD>е<EFBFBD>
** <EFBFBD><EFBFBD><EFBFBD><EFBFBD>(<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ)<EFBFBD>͹<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ṹ<EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD> 
*/
typedef struct URLContext
{
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Э<EFBFBD><EFBFBD>
    struct URLProtocol *prot;
    int flags;
    int max_packet_size; // if non zero, the stream is packetized with this max packet size
    void *priv_data;  // <EFBFBD><EFBFBD><EFBFBD><EFBFBD>file<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Э<EFBFBD>飬<EFBFBD>Ϳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    char filename[1]; // specified filename
} URLContext;

/* 
** URLЭ<EFBFBD>飨<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>׽<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>IJ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
** URLProtocol <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD>Э<EFBFBD>飬<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڹ<EFBFBD><EFBFBD>ܺ<EFBFBD><EFBFBD><EFBFBD>
** һ<EFBFBD>ֹ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD>Э<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧһ<EFBFBD><EFBFBD> URLProtocol <EFBFBD>ṹ<EFBFBD><EFBFBD>
** <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD> pipe<EFBFBD><EFBFBD>udp<EFBFBD><EFBFBD>tcp<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Э<EFBFBD>飬<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD> file Э<EFBFBD><EFBFBD>
*/
typedef struct URLProtocol
{
    const char *name;
    int(*url_open)(URLContext *h, const char *filename, int flags);
    int(*url_read)(URLContext *h, unsigned char *buf, int size);
    int(*url_write)(URLContext *h, unsigned char *buf, int size);
    offset_t(*url_seek)(URLContext *h, offset_t pos, int whence);
    int(*url_close)(URLContext *h);
    struct URLProtocol *next;
} URLProtocol;

/* 
** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ϵģ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ļ<EFBFBD>
*/
typedef struct ByteIOContext
{
	// <EFBFBD><EFBFBD><EFBFBD>ݻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    unsigned char *buffer;
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С
    int buffer_size;
	// <EFBFBD><EFBFBD>Ч<EFBFBD><EFBFBD><EFBFBD>ֽڷ<EFBFBD>Χ
    unsigned char *buf_ptr,  *buf_end;
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    void *opaque;
	// <EFBFBD><EFBFBD>ȡ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    int (*read_buf)(void *opaque, uint8_t *buf, int buf_size);
	// д<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    int (*write_buf)(void *opaque, uint8_t *buf, int buf_size);
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD>bufferָ<EFBFBD><EFBFBD>
    offset_t(*seek)(void *opaque, offset_t offset, int whence);
	// λ<EFBFBD><EFBFBD>
    offset_t pos;    // position in the file of the current buffer
	// <EFBFBD>Dz<EFBFBD><EFBFBD>DZ<EFBFBD><EFBFBD><EFBFBD>Ҫˢ<EFBFBD><EFBFBD>
    int must_flush;  // true if the next seek should flush
	// <EFBFBD>Ƿ񵽴<EFBFBD><EFBFBD>ļ<EFBFBD>β<EFBFBD><EFBFBD>
    int eof_reached; // true if eof reached
	// <EFBFBD>Ƿ<EFBFBD><EFBFBD><EFBFBD>д
    int write_flag;  // true if open for writing
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݰ<EFBFBD><EFBFBD>Ĵ<EFBFBD>С
    int max_packet_size;
	// <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    int error;       // contains the error code or 0 if no error happened
} ByteIOContext;

int url_open(URLContext **h, const char *filename, int flags);
int url_read(URLContext *h, unsigned char *buf, int size);
int url_write(URLContext *h, unsigned char *buf, int size);
offset_t url_seek(URLContext *h, offset_t pos, int whence);
int url_close(URLContext *h);
int url_get_max_packet_size(URLContext *h);

int register_protocol(URLProtocol *protocol);

int init_put_byte(ByteIOContext *s, 
				  unsigned char *buffer, 
				  int buffer_size, 
				  int write_flag, 
				  void *opaque, 
				  int(*read_buf)(void *opaque, uint8_t *buf, int buf_size),
				  int(*write_buf)(void *opaque, uint8_t *buf, int buf_size), 
				  offset_t(*seek)(void *opaque, offset_t offset, int whence));

offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence);
void url_fskip(ByteIOContext *s, offset_t offset);
offset_t url_ftell(ByteIOContext *s);
offset_t url_fsize(ByteIOContext *s);
int url_feof(ByteIOContext *s);
int url_ferror(ByteIOContext *s);

int url_fread(ByteIOContext *s, unsigned char *buf, int size); // get_buffer
int get_byte(ByteIOContext *s);
unsigned int get_le32(ByteIOContext *s);
unsigned int get_le16(ByteIOContext *s);

int url_setbufsize(ByteIOContext *s, int buf_size);
int url_fopen(ByteIOContext *s, const char *filename, int flags);
int url_fclose(ByteIOContext *s);

int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags);
int url_close_buf(ByteIOContext *s);

#endif