mirror of
https://git.code.sf.net/p/ntfs-3g/ntfs-3g.git
synced 2024-11-23 18:14:24 +08:00
393 lines
8.5 KiB
C
393 lines
8.5 KiB
C
/**
|
|
* unix_io.c - Unix style disk io functions. Originated from the Linux-NTFS project.
|
|
*
|
|
* Copyright (c) 2000-2006 Anton Altaparmakov
|
|
*
|
|
* This program/include file is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as published
|
|
* by the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program/include file 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program (in the main directory of the NTFS-3G
|
|
* distribution in the file COPYING); if not, write to the Free Software
|
|
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#ifdef HAVE_STDLIB_H
|
|
#include <stdlib.h>
|
|
#endif
|
|
#ifdef HAVE_STRING_H
|
|
#include <string.h>
|
|
#endif
|
|
#ifdef HAVE_ERRNO_H
|
|
#include <errno.h>
|
|
#endif
|
|
#ifdef HAVE_STDIO_H
|
|
#include <stdio.h>
|
|
#endif
|
|
#ifdef HAVE_SYS_TYPES_H
|
|
#include <sys/types.h>
|
|
#endif
|
|
#ifdef HAVE_SYS_STAT_H
|
|
#include <sys/stat.h>
|
|
#endif
|
|
#ifdef HAVE_FCNTL_H
|
|
#include <fcntl.h>
|
|
#endif
|
|
#ifdef HAVE_SYS_IOCTL_H
|
|
#include <sys/ioctl.h>
|
|
#endif
|
|
#ifdef HAVE_LINUX_FD_H
|
|
#include <linux/fd.h>
|
|
#endif
|
|
#ifdef HAVE_LINUX_FS_H
|
|
#include <linux/fs.h>
|
|
#endif
|
|
|
|
#include "types.h"
|
|
#include "mst.h"
|
|
#include "debug.h"
|
|
#include "device.h"
|
|
#include "logging.h"
|
|
#include "misc.h"
|
|
|
|
#define DEV_FD(dev) (*(int *)dev->d_private)
|
|
|
|
/* Define to nothing if not present on this system. */
|
|
#ifndef O_EXCL
|
|
# define O_EXCL 0
|
|
#endif
|
|
|
|
/**
|
|
* fsync replacement which makes every effort to try to get the data down to
|
|
* disk, using different means for different operating systems. Specifically,
|
|
* it issues the proper fcntl for Mac OS X or does fsync where it is available
|
|
* or as a last resort calls the fsync function. Information on this problem
|
|
* was retrieved from:
|
|
* http://mirror.linux.org.au/pub/linux.conf.au/2007/video/talks/278.pdf
|
|
*/
|
|
static int ntfs_fsync(int fildes)
|
|
{
|
|
int ret = -1;
|
|
#if defined(__APPLE__) || defined(__DARWIN__)
|
|
# ifndef F_FULLFSYNC
|
|
# error "Mac OS X: F_FULLFSYNC is not defined. Either you didn't include fcntl.h or you're using an older, unsupported version of Mac OS X (pre-10.3)."
|
|
# endif
|
|
/*
|
|
* Apple has disabled fsync() for internal disk drives in OS X.
|
|
* To force a synchronization of disk contents, we use a Mac OS X
|
|
* specific fcntl, F_FULLFSYNC.
|
|
*/
|
|
ret = fcntl(fildes, F_FULLFSYNC, NULL);
|
|
if (ret) {
|
|
/*
|
|
* If we are not on a file system that supports this,
|
|
* then fall back to a plain fsync.
|
|
*/
|
|
ret = fsync(fildes);
|
|
}
|
|
#else
|
|
ret = fsync(fildes);
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_open - Open a device and lock it exclusively
|
|
* @dev:
|
|
* @flags:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static int ntfs_device_unix_io_open(struct ntfs_device *dev, int flags)
|
|
{
|
|
struct flock flk;
|
|
struct stat sbuf;
|
|
int err;
|
|
|
|
if (NDevOpen(dev)) {
|
|
errno = EBUSY;
|
|
return -1;
|
|
}
|
|
if (stat(dev->d_name, &sbuf)) {
|
|
ntfs_log_perror("Failed to access '%s'", dev->d_name);
|
|
return -1;
|
|
}
|
|
if (S_ISBLK(sbuf.st_mode))
|
|
NDevSetBlock(dev);
|
|
|
|
dev->d_private = ntfs_malloc(sizeof(int));
|
|
if (!dev->d_private)
|
|
return -1;
|
|
/*
|
|
* Open file for exclusive access if mounting r/w.
|
|
* Fuseblk takes care about block devices.
|
|
*/
|
|
if (!NDevBlock(dev) && (flags & O_RDWR) == O_RDWR)
|
|
flags |= O_EXCL;
|
|
*(int*)dev->d_private = open(dev->d_name, flags);
|
|
if (*(int*)dev->d_private == -1) {
|
|
err = errno;
|
|
/* if permission error and rw, retry read-only */
|
|
if ((err == EACCES) && ((flags & O_RDWR) == O_RDWR))
|
|
err = EROFS;
|
|
goto err_out;
|
|
}
|
|
#ifdef HAVE_LINUX_FS_H
|
|
/* Check whether the device was forced read-only */
|
|
if (NDevBlock(dev) && ((flags & O_RDWR) == O_RDWR)) {
|
|
int r;
|
|
int state;
|
|
|
|
r = ioctl(DEV_FD(dev), BLKROGET, &state);
|
|
if (!r && state) {
|
|
err = EROFS;
|
|
if (close(DEV_FD(dev)))
|
|
err = errno;
|
|
goto err_out;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if ((flags & O_RDWR) != O_RDWR)
|
|
NDevSetReadOnly(dev);
|
|
|
|
memset(&flk, 0, sizeof(flk));
|
|
if (NDevReadOnly(dev))
|
|
flk.l_type = F_RDLCK;
|
|
else
|
|
flk.l_type = F_WRLCK;
|
|
flk.l_whence = SEEK_SET;
|
|
flk.l_start = flk.l_len = 0LL;
|
|
if (fcntl(DEV_FD(dev), F_SETLK, &flk)) {
|
|
err = errno;
|
|
ntfs_log_perror("Failed to %s lock '%s'", NDevReadOnly(dev) ?
|
|
"read" : "write", dev->d_name);
|
|
if (close(DEV_FD(dev)))
|
|
ntfs_log_perror("Failed to close '%s'", dev->d_name);
|
|
goto err_out;
|
|
}
|
|
|
|
NDevSetOpen(dev);
|
|
return 0;
|
|
err_out:
|
|
free(dev->d_private);
|
|
dev->d_private = NULL;
|
|
errno = err;
|
|
return -1;
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_close - Close the device, releasing the lock
|
|
* @dev:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static int ntfs_device_unix_io_close(struct ntfs_device *dev)
|
|
{
|
|
struct flock flk;
|
|
|
|
if (!NDevOpen(dev)) {
|
|
errno = EBADF;
|
|
ntfs_log_perror("Device %s is not open", dev->d_name);
|
|
return -1;
|
|
}
|
|
if (NDevDirty(dev))
|
|
if (ntfs_fsync(DEV_FD(dev))) {
|
|
ntfs_log_perror("Failed to fsync device %s", dev->d_name);
|
|
return -1;
|
|
}
|
|
|
|
memset(&flk, 0, sizeof(flk));
|
|
flk.l_type = F_UNLCK;
|
|
flk.l_whence = SEEK_SET;
|
|
flk.l_start = flk.l_len = 0LL;
|
|
if (fcntl(DEV_FD(dev), F_SETLK, &flk))
|
|
ntfs_log_perror("Could not unlock %s", dev->d_name);
|
|
if (close(DEV_FD(dev))) {
|
|
ntfs_log_perror("Failed to close device %s", dev->d_name);
|
|
return -1;
|
|
}
|
|
NDevClearOpen(dev);
|
|
free(dev->d_private);
|
|
dev->d_private = NULL;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_seek - Seek to a place on the device
|
|
* @dev:
|
|
* @offset:
|
|
* @whence:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static s64 ntfs_device_unix_io_seek(struct ntfs_device *dev, s64 offset,
|
|
int whence)
|
|
{
|
|
return lseek(DEV_FD(dev), offset, whence);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_read - Read from the device, from the current location
|
|
* @dev:
|
|
* @buf:
|
|
* @count:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static s64 ntfs_device_unix_io_read(struct ntfs_device *dev, void *buf,
|
|
s64 count)
|
|
{
|
|
return read(DEV_FD(dev), buf, count);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_write - Write to the device, at the current location
|
|
* @dev:
|
|
* @buf:
|
|
* @count:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static s64 ntfs_device_unix_io_write(struct ntfs_device *dev, const void *buf,
|
|
s64 count)
|
|
{
|
|
if (NDevReadOnly(dev)) {
|
|
errno = EROFS;
|
|
return -1;
|
|
}
|
|
NDevSetDirty(dev);
|
|
return write(DEV_FD(dev), buf, count);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_pread - Perform a positioned read from the device
|
|
* @dev:
|
|
* @buf:
|
|
* @count:
|
|
* @offset:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static s64 ntfs_device_unix_io_pread(struct ntfs_device *dev, void *buf,
|
|
s64 count, s64 offset)
|
|
{
|
|
return pread(DEV_FD(dev), buf, count, offset);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_pwrite - Perform a positioned write to the device
|
|
* @dev:
|
|
* @buf:
|
|
* @count:
|
|
* @offset:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static s64 ntfs_device_unix_io_pwrite(struct ntfs_device *dev, const void *buf,
|
|
s64 count, s64 offset)
|
|
{
|
|
if (NDevReadOnly(dev)) {
|
|
errno = EROFS;
|
|
return -1;
|
|
}
|
|
NDevSetDirty(dev);
|
|
return pwrite(DEV_FD(dev), buf, count, offset);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_sync - Flush any buffered changes to the device
|
|
* @dev:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static int ntfs_device_unix_io_sync(struct ntfs_device *dev)
|
|
{
|
|
int res = 0;
|
|
|
|
if (!NDevReadOnly(dev)) {
|
|
res = ntfs_fsync(DEV_FD(dev));
|
|
if (res)
|
|
ntfs_log_perror("Failed to sync device %s", dev->d_name);
|
|
else
|
|
NDevClearDirty(dev);
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_stat - Get information about the device
|
|
* @dev:
|
|
* @buf:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static int ntfs_device_unix_io_stat(struct ntfs_device *dev, struct stat *buf)
|
|
{
|
|
return fstat(DEV_FD(dev), buf);
|
|
}
|
|
|
|
/**
|
|
* ntfs_device_unix_io_ioctl - Perform an ioctl on the device
|
|
* @dev:
|
|
* @request:
|
|
* @argp:
|
|
*
|
|
* Description...
|
|
*
|
|
* Returns:
|
|
*/
|
|
static int ntfs_device_unix_io_ioctl(struct ntfs_device *dev, int request,
|
|
void *argp)
|
|
{
|
|
return ioctl(DEV_FD(dev), request, argp);
|
|
}
|
|
|
|
/**
|
|
* Device operations for working with unix style devices and files.
|
|
*/
|
|
struct ntfs_device_operations ntfs_device_unix_io_ops = {
|
|
.open = ntfs_device_unix_io_open,
|
|
.close = ntfs_device_unix_io_close,
|
|
.seek = ntfs_device_unix_io_seek,
|
|
.read = ntfs_device_unix_io_read,
|
|
.write = ntfs_device_unix_io_write,
|
|
.pread = ntfs_device_unix_io_pread,
|
|
.pwrite = ntfs_device_unix_io_pwrite,
|
|
.sync = ntfs_device_unix_io_sync,
|
|
.stat = ntfs_device_unix_io_stat,
|
|
.ioctl = ntfs_device_unix_io_ioctl,
|
|
};
|