You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
89 lines
1.9 KiB
89 lines
1.9 KiB
/*
|
|
** ffplay 把 file 当做类似于 rtsp，rtp，tcp 等协议的一种协议，用 file:前缀标示 file 协议。
|
|
** URLContext 结构抽象统一表示这些广义上的协议，对外提供统一的抽象接口。
|
|
** 各具体的广义协议实现文件实现 URLContext 接口。此文件实现了 file 广义协议的 URLContext 接口
|
|
*/
|
|
|
|
#include "../berrno.h"
|
|
|
|
#include "avformat.h"
|
|
#include <fcntl.h>
|
|
|
|
#ifndef CONFIG_WIN32
|
|
#include <unistd.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/time.h>
|
|
#else
|
|
#include <io.h>
|
|
#define open(fname,oflag,pmode) _open(fname,oflag,pmode)
|
|
#endif
|
|
|
|
/*
|
|
** 打开文件
|
|
*/
|
|
static int file_open(URLContext *h, const char *filename, int flags)
|
|
{
|
|
int access;
|
|
int fd;
|
|
|
|
// 搜索file协议
|
|
strstart(filename, "file:", &filename);
|
|
|
|
// 访问标志
|
|
if (flags &URL_RDWR)
|
|
access = O_CREAT | O_TRUNC | O_RDWR;
|
|
else if (flags &URL_WRONLY)
|
|
access = O_CREAT | O_TRUNC | O_WRONLY;
|
|
else
|
|
access = O_RDONLY;
|
|
#if defined(CONFIG_WIN32) || defined(CONFIG_OS2) || defined(__CYGWIN__)
|
|
access |= O_BINARY;
|
|
#endif
|
|
// 打开文件
|
|
fd = open(filename, access, 0666);
|
|
if (fd < 0)
|
|
return - ENOENT;
|
|
|
|
// 文件描述符赋给URLContext的priv_data
|
|
h->priv_data = (void*)(size_t)fd;
|
|
return 0;
|
|
}
|
|
|
|
/* 读取数据 */
|
|
static int file_read(URLContext *h, unsigned char *buf, int size)
|
|
{
|
|
int fd = (size_t)h->priv_data;
|
|
return read(fd, buf, size);
|
|
}
|
|
|
|
/* 写入数据 */
|
|
static int file_write(URLContext *h, unsigned char *buf, int size)
|
|
{
|
|
int fd = (size_t)h->priv_data;
|
|
return write(fd, buf, size);
|
|
}
|
|
|
|
/* 随机跳转 */
|
|
static offset_t file_seek(URLContext *h, offset_t pos, int whence)
|
|
{
|
|
int fd = (size_t)h->priv_data;
|
|
return lseek(fd, pos, whence);
|
|
}
|
|
|
|
/* 关闭文件 */
|
|
static int file_close(URLContext *h)
|
|
{
|
|
int fd = (size_t)h->priv_data;
|
|
return close(fd);
|
|
}
|
|
|
|
/* FILE类型的protocol */
|
|
URLProtocol file_protocol =
|
|
{
|
|
"file",
|
|
file_open,
|
|
file_read,
|
|
file_write,
|
|
file_seek,
|
|
file_close,
|
|
};
|
|
|