www.pudn.com > ffmpeg_c.rar > avio.h
/*
* unbuffered io for ffmpeg system
* 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 AVIO_H
#define AVIO_H
/* output byte stream handling */
typedef int64_t offset_t;
/* unbuffered I/O */
struct URLContext {
struct URLProtocol *prot;
int flags;
int is_streamed; /* true if streamed (no seek possible), default = false */
int max_packet_size; /* if non zero, the stream is packetized with this max packet size */
void *priv_data;
#if LIBAVFORMAT_VERSION_INT >= (52<<16)
char *filename; /* specified filename */
#else
char filename[1]; /* specified filename */
#endif
};
typedef struct URLContext URLContext;
typedef struct URLPollEntry {
URLContext *handle;
int events;
int revents;
} URLPollEntry;
#define URL_RDONLY 0
#define URL_WRONLY 1
#define URL_RDWR 2
typedef int URLInterruptCB(void);
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_exist(const char *filename);
offset_t url_filesize(URLContext *h);
int url_get_max_packet_size(URLContext *h);
void url_get_filename(URLContext *h, char *buf, int buf_size);
/* the callback is called in blocking functions to test regulary if
asynchronous interruption is needed. -EINTR is returned in this
case by the interrupted function. 'NULL' means no interrupt
callback is given. */
void url_set_interrupt_cb(URLInterruptCB *interrupt_cb);
/* not implemented */
int url_poll(URLPollEntry *poll_table, int n, int timeout);
/**
* passing this as the "whence" parameter to a seek function causes it to
* return the filesize without seeking anywhere, supporting this is optional
* if its not supprted then the seek function will return <0
*/
#define AVSEEK_SIZE 0x10000
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;
extern URLProtocol *first_protocol;
extern URLInterruptCB *url_interrupt_cb;
int register_protocol(URLProtocol *protocol);
typedef struct {
unsigned char *buffer;
int buffer_size;
unsigned char *buf_ptr, *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);
offset_t (*seek)(void *opaque, offset_t offset, int whence);
offset_t pos; /* position in the file of the current buffer */
int must_flush; /* true if the next seek should flush */
int eof_reached; /* true if eof reached */
int write_flag; /* true if open for writing */
int is_streamed;
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; ///< contains the error code or 0 if no error happened
} ByteIOContext;
int init_put_byte(ByteIOContext *s,
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),
offset_t (*seek)(void *opaque, offset_t offset, int whence));
void put_byte(ByteIOContext *s, int b);
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size);
void put_le64(ByteIOContext *s, uint64_t val);
void put_be64(ByteIOContext *s, uint64_t val);
void put_le32(ByteIOContext *s, unsigned int val);
void put_be32(ByteIOContext *s, unsigned int val);
void put_le24(ByteIOContext *s, unsigned int val);
void put_be24(ByteIOContext *s, unsigned int val);
void put_le16(ByteIOContext *s, unsigned int val);
void put_be16(ByteIOContext *s, unsigned int val);
void put_tag(ByteIOContext *s, const char *tag);
void put_strz(ByteIOContext *s, const char *buf);
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);
#define URL_EOF (-1)
int url_fgetc(ByteIOContext *s);
#ifdef __GNUC__
int url_fprintf(ByteIOContext *s, const char *fmt, ...) __attribute__ ((__format__ (__printf__, 2, 3)));
#else
int url_fprintf(ByteIOContext *s, const char *fmt, ...);
#endif
char *url_fgets(ByteIOContext *s, char *buf, int buf_size);
void put_flush_packet(ByteIOContext *s);
int get_buffer(ByteIOContext *s, unsigned char *buf, int size);
int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size);
int get_byte(ByteIOContext *s);
unsigned int get_le24(ByteIOContext *s);
unsigned int get_le32(ByteIOContext *s);
uint64_t get_le64(ByteIOContext *s);
unsigned int get_le16(ByteIOContext *s);
char *get_strz(ByteIOContext *s, char *buf, int maxlen);
unsigned int get_be16(ByteIOContext *s);
unsigned int get_be24(ByteIOContext *s);
unsigned int get_be32(ByteIOContext *s);
uint64_t get_be64(ByteIOContext *s);
static inline int url_is_streamed(ByteIOContext *s)
{
return s->is_streamed;
}
int url_fdopen(ByteIOContext *s, URLContext *h);
int url_setbufsize(ByteIOContext *s, int buf_size);
int url_fopen(ByteIOContext *s, const char *filename, int flags);
int url_fclose(ByteIOContext *s);
URLContext *url_fileno(ByteIOContext *s);
int url_fget_max_packet_size(ByteIOContext *s);
int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags);
int url_close_buf(ByteIOContext *s);
int url_open_dyn_buf(ByteIOContext *s);
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size);
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer);
unsigned long get_checksum(ByteIOContext *s);
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum);
/* file.c */
extern URLProtocol file_protocol;
extern URLProtocol pipe_protocol;
/* udp.c */
extern URLProtocol udp_protocol;
int udp_set_remote_url(URLContext *h, const char *uri);
int udp_get_local_port(URLContext *h);
int udp_get_file_handle(URLContext *h);
/* tcp.c */
extern URLProtocol tcp_protocol;
/* http.c */
extern URLProtocol http_protocol;
#endif