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/*
* buffered file I/O
* 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
*/
#include "libavutil/avstring.h"
#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "avformat.h"
#include <fcntl.h>
#if HAVE_IO_H
#include <io.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/stat.h>
#include <stdlib.h>
#include "os_support.h"
#include "url.h"
/* Some systems may not have S_ISFIFO */
#ifndef S_ISFIFO
# ifdef S_IFIFO
# define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
# else
# define S_ISFIFO(m) 0
# endif
#endif
/* standard file protocol */
typedef struct FileContext {
const AVClass *class;
int fd;
int trunc;
int blocksize;
} FileContext;
static const AVOption file_options[] = {
{ "truncate", "truncate existing files on write", offsetof(FileContext, trunc), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, AV_OPT_FLAG_ENCODING_PARAM },
{ "blocksize", "set I/O operation maximum block size", offsetof(FileContext, blocksize), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
{ NULL }
};
static const AVOption pipe_options[] = {
{ "blocksize", "set I/O operation maximum block size", offsetof(FileContext, blocksize), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
{ NULL }
};
static const AVClass file_class = {
.class_name = "file",
.item_name = av_default_item_name,
.option = file_options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVClass pipe_class = {
.class_name = "pipe",
.item_name = av_default_item_name,
.option = pipe_options,
.version = LIBAVUTIL_VERSION_INT,
};
static int file_read(URLContext *h, unsigned char *buf, int size)
{
FileContext *c = h->priv_data;
int r;
size = FFMIN(size, c->blocksize);
r = read(c->fd, buf, size);
return (-1 == r)?AVERROR(errno):r;
}
static int file_write(URLContext *h, const unsigned char *buf, int size)
{
FileContext *c = h->priv_data;
int r;
size = FFMIN(size, c->blocksize);
r = write(c->fd, buf, size);
return (-1 == r)?AVERROR(errno):r;
}
static int file_get_handle(URLContext *h)
{
FileContext *c = h->priv_data;
return c->fd;
}
static int file_check(URLContext *h, int mask)
{
int ret = 0;
const char *filename = h->filename;
av_strstart(filename, "file:", &filename);
{
#if HAVE_ACCESS && defined(R_OK)
if (access(filename, F_OK) < 0)
return AVERROR(errno);
if (mask&AVIO_FLAG_READ)
if (access(filename, R_OK) >= 0)
ret |= AVIO_FLAG_READ;
if (mask&AVIO_FLAG_WRITE)
if (access(filename, W_OK) >= 0)
ret |= AVIO_FLAG_WRITE;
#else
struct stat st;
ret = stat(filename, &st);
if (ret < 0)
return AVERROR(errno);
ret |= st.st_mode&S_IRUSR ? mask&AVIO_FLAG_READ : 0;
ret |= st.st_mode&S_IWUSR ? mask&AVIO_FLAG_WRITE : 0;
#endif
}
return ret;
}
#if CONFIG_FILE_PROTOCOL
static int file_open(URLContext *h, const char *filename, int flags)
{
FileContext *c = h->priv_data;
int access;
int fd;
struct stat st;
av_strstart(filename, "file:", &filename);
if (flags & AVIO_FLAG_WRITE && flags & AVIO_FLAG_READ) {
access = O_CREAT | O_RDWR;
if (c->trunc)
access |= O_TRUNC;
} else if (flags & AVIO_FLAG_WRITE) {
access = O_CREAT | O_WRONLY;
if (c->trunc)
access |= O_TRUNC;
} else {
access = O_RDONLY;
}
#ifdef O_BINARY
access |= O_BINARY;
#endif
fd = avpriv_open(filename, access, 0666);
if (fd == -1)
return AVERROR(errno);
c->fd = fd;
h->is_streamed = !fstat(fd, &st) && S_ISFIFO(st.st_mode);
return 0;
}
/* XXX: use llseek */
static int64_t file_seek(URLContext *h, int64_t pos, int whence)
{
FileContext *c = h->priv_data;
int64_t ret;
if (whence == AVSEEK_SIZE) {
struct stat st;
ret = fstat(c->fd, &st);
return ret < 0 ? AVERROR(errno) : (S_ISFIFO(st.st_mode) ? 0 : st.st_size);
}
ret = lseek(c->fd, pos, whence);
return ret < 0 ? AVERROR(errno) : ret;
}
static int file_close(URLContext *h)
{
FileContext *c = h->priv_data;
return close(c->fd);
}
URLProtocol ff_file_protocol = {
.name = "file",
.url_open = file_open,
.url_read = file_read,
.url_write = file_write,
.url_seek = file_seek,
.url_close = file_close,
.url_get_file_handle = file_get_handle,
.url_check = file_check,
.priv_data_size = sizeof(FileContext),
.priv_data_class = &file_class,
};
#endif /* CONFIG_FILE_PROTOCOL */
#if CONFIG_PIPE_PROTOCOL
static int pipe_open(URLContext *h, const char *filename, int flags)
{
FileContext *c = h->priv_data;
int fd;
char *final;
av_strstart(filename, "pipe:", &filename);
fd = strtol(filename, &final, 10);
if((filename == final) || *final ) {/* No digits found, or something like 10ab */
if (flags & AVIO_FLAG_WRITE) {
fd = 1;
} else {
fd = 0;
}
}
#if HAVE_SETMODE
setmode(fd, O_BINARY);
#endif
c->fd = fd;
h->is_streamed = 1;
return 0;
}
URLProtocol ff_pipe_protocol = {
.name = "pipe",
.url_open = pipe_open,
.url_read = file_read,
.url_write = file_write,
.url_get_file_handle = file_get_handle,
.url_check = file_check,
.priv_data_size = sizeof(FileContext),
.priv_data_class = &pipe_class,
};
#endif /* CONFIG_PIPE_PROTOCOL */