busybox/util-linux/volume_id/volume_id.c
Denis Vlasenko 582dff0514 volume identification: abolish /proc/partitions and /proc/cdroms
scanning. It does not catch volume managers and such.
Adding even more cruft is bad, so I decided to simply
scan /dev/* for any block devices. See how much better
it finds devices now:

# ./busybox_old blkid
/dev/sda1: LABEL="/boot" UUID="7931e231-dcb4-4b6d-9301-f7354ae24061"
/dev/dm-0: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a"
/dev/dm-1: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267"
/dev/sdb1: UUID="6F84-ED0F"

# ./busybox blkid
/dev/sdb1: UUID="6F84-ED0F"
/dev/root: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a"
/dev/dm-1: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267"
/dev/dm-0: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a"
/dev/sda1: LABEL="/boot" UUID="7931e231-dcb4-4b6d-9301-f7354ae24061"
/dev/mapper/VolGroup00-LogVol01: UUID="edc2a920-ef83-437e-ba64-d3b6dc851267"
/dev/mapper/VolGroup00-LogVol00: LABEL="Fedora-9-Live-x8" UUID="bb491e1e-1145-4f5b-b0ab-cbd2baf4f15a"

function                                             old     new   delta
static.drive_name_string                              12       -     -12
append_mount_options                                 205     190     -15
volume_id_open_node                                   37      18     -19
uuidcache_check_device                               485     257    -228
uuidcache_init                                       637      36    -601
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 0/4 up/down: 0/-875)           Total: -875 bytes
   text    data     bss     dec     hex filename
 792218     592    6648  799458   c32e2 busybox_old
 791260     592    6648  798500   c2f24 busybox_unstripped
2008-10-19 19:36:30 +00:00

239 lines
6.0 KiB
C

/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
*
* This library 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.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "volume_id_internal.h"
/* Some detection routines do not set label or uuid anyway,
* so they are disabled. */
/* Looks for partitions, we don't use it: */
#define ENABLE_FEATURE_VOLUMEID_MAC 0
/* #define ENABLE_FEATURE_VOLUMEID_MSDOS 0 - NB: this one
* was not properly added to probe table anyway - ??! */
/* None of RAIDs have label or uuid, except LinuxRAID: */
#define ENABLE_FEATURE_VOLUMEID_HIGHPOINTRAID 0
#define ENABLE_FEATURE_VOLUMEID_ISWRAID 0
#define ENABLE_FEATURE_VOLUMEID_LSIRAID 0
#define ENABLE_FEATURE_VOLUMEID_LVM 0
#define ENABLE_FEATURE_VOLUMEID_NVIDIARAID 0
#define ENABLE_FEATURE_VOLUMEID_PROMISERAID 0
#define ENABLE_FEATURE_VOLUMEID_SILICONRAID 0
#define ENABLE_FEATURE_VOLUMEID_VIARAID 0
/* These filesystems also have no label or uuid: */
#define ENABLE_FEATURE_VOLUMEID_MINIX 0
#define ENABLE_FEATURE_VOLUMEID_HPFS 0
#define ENABLE_FEATURE_VOLUMEID_UFS 0
typedef int (*raid_probe_fptr)(struct volume_id *id, uint64_t off, uint64_t size);
typedef int (*probe_fptr)(struct volume_id *id, uint64_t off);
static const raid_probe_fptr raid1[] = {
#if ENABLE_FEATURE_VOLUMEID_LINUXRAID
volume_id_probe_linux_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_ISWRAID
volume_id_probe_intel_software_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_LSIRAID
volume_id_probe_lsi_mega_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_VIARAID
volume_id_probe_via_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_SILICONRAID
volume_id_probe_silicon_medley_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_NVIDIARAID
volume_id_probe_nvidia_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_PROMISERAID
volume_id_probe_promise_fasttrack_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_HIGHPOINTRAID
volume_id_probe_highpoint_45x_raid,
#endif
};
static const probe_fptr raid2[] = {
#if ENABLE_FEATURE_VOLUMEID_LVM
volume_id_probe_lvm1,
volume_id_probe_lvm2,
#endif
#if ENABLE_FEATURE_VOLUMEID_HIGHPOINTRAID
volume_id_probe_highpoint_37x_raid,
#endif
#if ENABLE_FEATURE_VOLUMEID_LUKS
volume_id_probe_luks,
#endif
};
/* signature in the first block, only small buffer needed */
static const probe_fptr fs1[] = {
#if ENABLE_FEATURE_VOLUMEID_FAT
volume_id_probe_vfat,
#endif
#if ENABLE_FEATURE_VOLUMEID_MAC
volume_id_probe_mac_partition_map,
#endif
#if ENABLE_FEATURE_VOLUMEID_XFS
volume_id_probe_xfs,
#endif
};
/* fill buffer with maximum */
static const probe_fptr fs2[] = {
#if ENABLE_FEATURE_VOLUMEID_LINUXSWAP
volume_id_probe_linux_swap,
#endif
#if ENABLE_FEATURE_VOLUMEID_EXT
volume_id_probe_ext,
#endif
#if ENABLE_FEATURE_VOLUMEID_REISERFS
volume_id_probe_reiserfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_JFS
volume_id_probe_jfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_UDF
volume_id_probe_udf,
#endif
#if ENABLE_FEATURE_VOLUMEID_ISO9660
volume_id_probe_iso9660,
#endif
#if ENABLE_FEATURE_VOLUMEID_HFS
volume_id_probe_hfs_hfsplus,
#endif
#if ENABLE_FEATURE_VOLUMEID_UFS
volume_id_probe_ufs,
#endif
#if ENABLE_FEATURE_VOLUMEID_NTFS
volume_id_probe_ntfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_CRAMFS
volume_id_probe_cramfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_ROMFS
volume_id_probe_romfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_HPFS
volume_id_probe_hpfs,
#endif
#if ENABLE_FEATURE_VOLUMEID_SYSV
volume_id_probe_sysv,
#endif
#if ENABLE_FEATURE_VOLUMEID_MINIX
volume_id_probe_minix,
#endif
#if ENABLE_FEATURE_VOLUMEID_OCFS2
volume_id_probe_ocfs2,
#endif
};
int volume_id_probe_all(struct volume_id *id, uint64_t off, uint64_t size)
{
unsigned i;
if (id == NULL)
return -EINVAL;
/* probe for raid first, cause fs probes may be successful on raid members */
if (size) {
for (i = 0; i < ARRAY_SIZE(raid1); i++)
if (raid1[i](id, off, size) == 0)
goto ret;
}
for (i = 0; i < ARRAY_SIZE(raid2); i++)
if (raid2[i](id, off) == 0)
goto ret;
/* signature in the first block, only small buffer needed */
for (i = 0; i < ARRAY_SIZE(fs1); i++)
if (fs1[i](id, off) == 0)
goto ret;
/* fill buffer with maximum */
volume_id_get_buffer(id, 0, SB_BUFFER_SIZE);
for (i = 0; i < ARRAY_SIZE(fs2); i++)
if (fs2[i](id, off) == 0)
goto ret;
return -1;
ret:
/* If the filestystem in recognized, we free the allocated buffers,
otherwise they will stay in place for the possible next probe call */
volume_id_free_buffer(id);
return 0;
}
/* open volume by device node */
struct volume_id *volume_id_open_node(int fd)
{
struct volume_id *id;
id = xzalloc(sizeof(struct volume_id));
id->fd = fd;
///* close fd on device close */
//id->fd_close = 1;
return id;
}
#ifdef UNUSED
/* open volume by major/minor */
struct volume_id *volume_id_open_dev_t(dev_t devt)
{
struct volume_id *id;
char *tmp_node[VOLUME_ID_PATH_MAX];
tmp_node = xasprintf("/dev/.volume_id-%u-%u-%u",
(unsigned)getpid(), (unsigned)major(devt), (unsigned)minor(devt));
/* create temporary node to open block device */
unlink(tmp_node);
if (mknod(tmp_node, (S_IFBLK | 0600), devt) != 0)
bb_perror_msg_and_die("cannot mknod(%s)", tmp_node);
id = volume_id_open_node(tmp_node);
unlink(tmp_node);
free(tmp_node);
return id;
}
#endif
void free_volume_id(struct volume_id *id)
{
if (id == NULL)
return;
//if (id->fd_close != 0) - always true
close(id->fd);
volume_id_free_buffer(id);
#ifdef UNUSED_PARTITION_CODE
free(id->partitions);
#endif
free(id);
}