1  /*
       2   * uktrix partition parsing code
       3   *
       4   * Copyright (C) 2010 Karel Zak <kzak@redhat.com>
       5   *
       6   * This file may be redistributed under the terms of the
       7   * GNU Lesser General Public License.
       8   *
       9   */
      10  #include <stdio.h>
      11  #include <string.h>
      12  #include <stdlib.h>
      13  #include <stdint.h>
      14  
      15  #include "partitions.h"
      16  
      17  #define ULTRIX_MAXPARTITIONS	8
      18  
      19  #define ULTRIX_MAGIC		0x032957
      20  #define ULTRIX_MAGIC_STR	"\x02\x29\x57"
      21  
      22  /* sector with partition table */
      23  #define ULTRIX_SECTOR		((16384 - sizeof(struct ultrix_disklabel)) >> 9)
      24  /* position of partition table within ULTRIX_SECTOR */
      25  #define ULTRIX_OFFSET		(512 - sizeof(struct ultrix_disklabel))
      26  
      27  struct ultrix_disklabel {
      28  	int32_t	pt_magic;	/* magic no. indicating part. info exits */
      29  	int32_t	pt_valid;	/* set by driver if pt is current */
      30  	struct  pt_info {
      31  		int32_t		pi_nblocks; /* no. of sectors */
      32  		uint32_t	pi_blkoff;  /* block offset for start */
      33  	} pt_part[ULTRIX_MAXPARTITIONS];
      34  } __attribute__((packed));
      35  
      36  
      37  static int probe_ultrix_pt(blkid_probe pr,
      38  		const struct blkid_idmag *mag __attribute__((__unused__)))
      39  {
      40  	unsigned char *data;
      41  	struct ultrix_disklabel *l;
      42  	blkid_parttable tab = NULL;
      43  	blkid_partlist ls;
      44  	int i;
      45  
      46  	data = blkid_probe_get_sector(pr, ULTRIX_SECTOR);
      47  	if (!data) {
      48  		if (errno)
      49  			return -errno;
      50  		goto nothing;
      51  	}
      52  
      53  	l = (struct ultrix_disklabel *) (data + ULTRIX_OFFSET);
      54  
      55  	if (l->pt_magic != ULTRIX_MAGIC || l->pt_valid != 1)
      56  		goto nothing;
      57  
      58  	if (blkid_probe_set_magic(pr, (ULTRIX_SECTOR << 9) + ULTRIX_OFFSET,
      59  			sizeof(ULTRIX_MAGIC_STR) - 1,
      60  			(unsigned char *) ULTRIX_MAGIC_STR))
      61  		goto err;
      62  
      63  	if (blkid_partitions_need_typeonly(pr))
      64  		/* caller does not ask for details about partitions */
      65  		return BLKID_PROBE_OK;
      66  
      67  	ls = blkid_probe_get_partlist(pr);
      68  	if (!ls)
      69  		goto nothing;
      70  
      71  	tab = blkid_partlist_new_parttable(ls, "ultrix", 0);
      72  	if (!tab)
      73  		goto err;
      74  
      75  	for (i = 0; i < ULTRIX_MAXPARTITIONS; i++) {
      76  		if (!l->pt_part[i].pi_nblocks)
      77  			 blkid_partlist_increment_partno(ls);
      78  		else {
      79  			if (!blkid_partlist_add_partition(ls, tab,
      80  						l->pt_part[i].pi_blkoff,
      81  						l->pt_part[i].pi_nblocks))
      82  				goto err;
      83  		}
      84  	}
      85  
      86  	return BLKID_PROBE_OK;
      87  nothing:
      88  	return BLKID_PROBE_NONE;
      89  err:
      90  	return -ENOMEM;
      91  }
      92  
      93  const struct blkid_idinfo ultrix_pt_idinfo =
      94  {
      95  	.name		= "ultrix",
      96  	.probefunc	= probe_ultrix_pt,
      97  	.magics		= BLKID_NONE_MAGIC
      98  };
      99