busybox/util-linux/volume_id/udf.c
Denys Vlasenko f560422fa0 Big cleanup in config help and description
Redundant help texts (one which only repeats the description)
are deleted.

Descriptions and help texts are trimmed.

Some config options are moved, even across menus.

No config option _names_ are changed.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-01-10 14:58:54 +01:00

180 lines
4.5 KiB
C

/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2004 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
*/
//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_UDF) += udf.o
//config:config FEATURE_VOLUMEID_UDF
//config: bool "udf filesystem"
//config: default y
//config: depends on VOLUMEID
#include "volume_id_internal.h"
struct volume_descriptor {
struct descriptor_tag {
uint16_t id;
uint16_t version;
uint8_t checksum;
uint8_t reserved;
uint16_t serial;
uint16_t crc;
uint16_t crc_len;
uint32_t location;
} PACKED tag;
union {
struct anchor_descriptor {
uint32_t length;
uint32_t location;
} PACKED anchor;
struct primary_descriptor {
uint32_t seq_num;
uint32_t desc_num;
struct dstring {
uint8_t clen;
uint8_t c[31];
} PACKED ident;
} PACKED primary;
} PACKED type;
} PACKED;
struct volume_structure_descriptor {
uint8_t type;
uint8_t id[5];
uint8_t version;
} PACKED;
#define UDF_VSD_OFFSET 0x8000
int FAST_FUNC volume_id_probe_udf(struct volume_id *id /*,uint64_t off*/)
{
#define off ((uint64_t)0)
struct volume_descriptor *vd;
struct volume_structure_descriptor *vsd;
unsigned bs;
unsigned b;
unsigned type;
unsigned count;
unsigned loc;
unsigned clen;
dbg("probing at offset 0x%llx", (unsigned long long) off);
vsd = volume_id_get_buffer(id, off + UDF_VSD_OFFSET, 0x200);
if (vsd == NULL)
return -1;
if (memcmp(vsd->id, "NSR02", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "NSR03", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "BEA01", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "BOOT2", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "CD001", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "CDW02", 5) == 0)
goto blocksize;
if (memcmp(vsd->id, "TEA03", 5) == 0)
goto blocksize;
return -1;
blocksize:
/* search the next VSD to get the logical block size of the volume */
for (bs = 0x800; bs < 0x8000; bs += 0x800) {
vsd = volume_id_get_buffer(id, off + UDF_VSD_OFFSET + bs, 0x800);
if (vsd == NULL)
return -1;
dbg("test for blocksize: 0x%x", bs);
if (vsd->id[0] != '\0')
goto nsr;
}
return -1;
nsr:
/* search the list of VSDs for a NSR descriptor */
for (b = 0; b < 64; b++) {
vsd = volume_id_get_buffer(id, off + UDF_VSD_OFFSET + (b * bs), 0x800);
if (vsd == NULL)
return -1;
dbg("vsd: %c%c%c%c%c",
vsd->id[0], vsd->id[1], vsd->id[2], vsd->id[3], vsd->id[4]);
if (vsd->id[0] == '\0')
return -1;
if (memcmp(vsd->id, "NSR02", 5) == 0)
goto anchor;
if (memcmp(vsd->id, "NSR03", 5) == 0)
goto anchor;
}
return -1;
anchor:
/* read anchor volume descriptor */
vd = volume_id_get_buffer(id, off + (256 * bs), 0x200);
if (vd == NULL)
return -1;
type = le16_to_cpu(vd->tag.id);
if (type != 2) /* TAG_ID_AVDP */
goto found;
/* get desriptor list address and block count */
count = le32_to_cpu(vd->type.anchor.length) / bs;
loc = le32_to_cpu(vd->type.anchor.location);
dbg("0x%x descriptors starting at logical secor 0x%x", count, loc);
/* pick the primary descriptor from the list */
for (b = 0; b < count; b++) {
vd = volume_id_get_buffer(id, off + ((loc + b) * bs), 0x200);
if (vd == NULL)
return -1;
type = le16_to_cpu(vd->tag.id);
dbg("descriptor type %i", type);
/* check validity */
if (type == 0)
goto found;
if (le32_to_cpu(vd->tag.location) != loc + b)
goto found;
if (type == 1) /* TAG_ID_PVD */
goto pvd;
}
goto found;
pvd:
// volume_id_set_label_raw(id, &(vd->type.primary.ident.clen), 32);
clen = vd->type.primary.ident.clen;
dbg("label string charsize=%i bit", clen);
if (clen == 8)
volume_id_set_label_string(id, vd->type.primary.ident.c, 31);
else if (clen == 16)
volume_id_set_label_unicode16(id, vd->type.primary.ident.c, BE, 31);
found:
// volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
IF_FEATURE_BLKID_TYPE(id->type = "udf";)
return 0;
}