busybox/util-linux/volume_id/minix.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
 */
//config:config FEATURE_VOLUMEID_MINIX
//config:	bool "minix filesystem"
//config:	default y
//config:	depends on VOLUMEID

//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_MINIX) += minix.o

#include "volume_id_internal.h"

struct minix_super_block {
	uint16_t	s_ninodes;
	uint16_t	s_nzones;
	uint16_t	s_imap_blocks;
	uint16_t	s_zmap_blocks;
	uint16_t	s_firstdatazone;
	uint16_t	s_log_zone_size;
	uint32_t	s_max_size;
	uint16_t	s_magic;
	uint16_t	s_state;
	uint32_t	s_zones;
} PACKED;

/* V3 minix super-block data on disk */
struct minix3_super_block {
	uint32_t	s_ninodes;
	uint16_t	s_pad0;
	uint16_t	s_imap_blocks;
	uint16_t	s_zmap_blocks;
	uint16_t	s_firstdatazone;
	uint16_t	s_log_zone_size;
	uint16_t	s_pad1;
	uint32_t	s_max_size;
	uint32_t	s_zones;
	uint16_t	s_magic;
	uint16_t	s_pad2;
	uint16_t	s_blocksize;
	uint8_t		s_disk_version;
} PACKED;

#define MINIX_SUPERBLOCK_OFFSET 0x400

int FAST_FUNC volume_id_probe_minix(struct volume_id *id /*, uint64_t off*/)
{
#define off ((uint64_t)0)
	struct minix_super_block *ms;
	struct minix3_super_block *ms3;

	dbg("probing at offset 0x%llx", (unsigned long long) off);

	ms = volume_id_get_buffer(id, off + MINIX_SUPERBLOCK_OFFSET, 0x200);
	if (ms == NULL)
		return -1;
	if (ms->s_magic == cpu_to_le16(0x137F)) /* minix V1 fs, 14 char names */
		goto found;
	if (ms->s_magic == cpu_to_le16(0x138F)) /* minix V1 fs, 30 char names */
		goto found;
	if (ms->s_magic == cpu_to_le16(0x2468)) /* minix V2 fs, 14 char names */
		goto found;
	if (ms->s_magic == cpu_to_le16(0x2478)) /* minix V2 fs, 30 char names */
		goto found;

	ms3 = (void*)ms;
	if (ms3->s_magic == cpu_to_le16(0x4d5a)) /* minix V3 fs, 60 char names */
		goto found;

	return -1;

 found:
//	volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
	IF_FEATURE_BLKID_TYPE(id->type = "minix";)
	return 0;
}