freebsd-dev/sys/geom/label/g_label_msdosfs.c
2006-02-01 12:06:01 +00:00

102 lines
3.0 KiB
C

/*-
* Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <geom/geom.h>
#include <geom/label/g_label.h>
#define G_LABEL_MSDOSFS_DIR "msdosfs"
#define FAT12 "FAT12 "
#define FAT16 "FAT16 "
#define FAT32 "FAT32 "
#define VOLUME_LEN 11
#define NO_NAME "NO NAME "
static void
g_label_msdosfs_taste(struct g_consumer *cp, char *label, size_t size)
{
struct g_provider *pp;
char *sector, *volume;
int i;
g_topology_assert_not();
pp = cp->provider;
label[0] = '\0';
sector = (char *)g_read_data(cp, 0, pp->sectorsize, NULL);
if (sector == NULL)
return;
if (strncmp(sector + 0x36, FAT12, strlen(FAT12)) == 0) {
G_LABEL_DEBUG(1, "MSDOS (FAT12) file system detected on %s.",
pp->name);
volume = sector + 0x2b;
} else if (strncmp(sector + 0x36, FAT16, strlen(FAT16)) == 0) {
G_LABEL_DEBUG(1, "MSDOS (FAT16) file system detected on %s.",
pp->name);
volume = sector + 0x2b;
} else if (strncmp(sector + 0x52, FAT32, strlen(FAT32)) == 0) {
G_LABEL_DEBUG(1, "MSDOS (FAT32) file system detected on %s.",
pp->name);
volume = sector + 0x47;
} else {
g_free(sector);
return;
}
if (strncmp(volume, NO_NAME, VOLUME_LEN) == 0) {
g_free(sector);
return;
}
if (volume[0] == '\0') {
g_free(sector);
return;
}
bzero(label, size);
strlcpy(label, volume, MIN(size, VOLUME_LEN));
g_free(sector);
for (i = size - 1; i > 0; i--) {
if (label[i] == '\0')
continue;
else if (label[i] == ' ')
label[i] = '\0';
else
break;
}
}
const struct g_label_desc g_label_msdosfs = {
.ld_taste = g_label_msdosfs_taste,
.ld_dir = G_LABEL_MSDOSFS_DIR
};