freebsd-dev/usr.bin/fstat/msdosfs.c
David Malone b628b0dce5 Anding the fsid with 0xffff was causing aliasing problems.
PR:		17405, 16320
Submitted by:	Mark W. Krentel <krentel@dreamscape.com>
Submitted by:	Peter Edwards <peter.edwards@ireland.com>
MFC after:	2 weeks
2001-11-05 20:40:24 +00:00

151 lines
4.7 KiB
C

/*
* Copyright (c) 2000 Peter Edwards
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by Peter Edwards
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#define _KERNEL
#include <sys/mount.h>
#include <fs/msdosfs/bpb.h>
#include <fs/msdosfs/msdosfsmount.h>
#undef _KERNEL
#include <fs/msdosfs/denode.h>
#include <fs/msdosfs/direntry.h>
#include <fs/msdosfs/fat.h>
#include <err.h>
#include <kvm.h>
#include <stdio.h>
#include <stdlib.h>
/*
* XXX -
* VTODE is defined in denode.h only if _KERNEL is defined, but that leads to
* header explosion
*/
#define VTODE(vp) ((struct denode *)(vp)->v_data)
#include "fstat.h"
struct dosmount {
struct dosmount *next;
struct msdosfsmount *kptr; /* Pointer in kernel space */
struct msdosfsmount data; /* User space copy of structure */
};
int
msdosfs_filestat(vp, fsp)
struct vnode *vp;
struct filestat *fsp;
{
struct denode denode;
static struct dosmount *mounts;
struct dosmount *mnt;
u_long dirsperblk;
int fileid;
if (!KVM_READ(VTODE(vp), &denode, sizeof (denode))) {
dprintf(stderr, "can't read denode at %p for pid %d\n",
(void *)VTODE(vp), Pid);
return 0;
}
/*
* Find msdosfsmount structure for the vnode's filesystem. Needed
* for some filesystem parameters
*/
for (mnt = mounts; mnt; mnt = mnt->next)
if (mnt->kptr == denode.de_pmp)
break;
if (!mnt) {
if ((mnt = malloc(sizeof(struct dosmount))) == NULL)
err(1, NULL);
mnt->next = mounts;
mounts = mnt;
mnt->kptr = denode.de_pmp;
if (!KVM_READ(denode.de_pmp, &mnt->data, sizeof mnt->data)) {
dprintf(stderr,
"can't read mount info at %p for pid %d\n",
(void *)denode.de_pmp, Pid);
return 0;
}
}
fsp->fsid = dev2udev(denode.de_dev);
fsp->mode = 0555;
fsp->mode |= denode.de_Attributes & ATTR_READONLY ? 0 : 0222;
fsp->mode &= mnt->data.pm_mask;
/* Distinguish directories and files. No "special" files in FAT. */
fsp->mode |= denode.de_Attributes & ATTR_DIRECTORY ? S_IFDIR : S_IFREG;
fsp->size = denode.de_FileSize;
fsp->rdev = denode.de_dev;
/*
* XXX -
* Culled from msdosfs_vnops.c. There appears to be a problem
* here, in that a directory has the same inode number as the first
* file in the directory. stat(2) suffers from this problem also, so
* I won't try to fix it here.
*
* The following computation of the fileid must be the same as that
* used in msdosfs_readdir() to compute d_fileno. If not, pwd
* doesn't work.
*/
dirsperblk = mnt->data.pm_BytesPerSec / sizeof(struct direntry);
if (denode.de_Attributes & ATTR_DIRECTORY) {
fileid = cntobn(&mnt->data, denode.de_StartCluster)
* dirsperblk;
if (denode.de_StartCluster == MSDOSFSROOT)
fileid = 1;
} else {
fileid = cntobn(&mnt->data, denode.de_dirclust) * dirsperblk;
if (denode.de_dirclust == MSDOSFSROOT)
fileid = roottobn(&mnt->data, 0) * dirsperblk;
fileid += denode.de_diroffset / sizeof(struct direntry);
}
fsp->fileid = fileid;
return 1;
}