/*

 * Copyright (C) 2008 Karel Zak <kzak@redhat.com>

 *

 * This is written from scratch according to Linux kernel fs/sysv/super.c file.

 * It seems that sysv probing code in libvolume_id and also in the original

 * blkid is useless.

 *

 * This file may be redistributed under the terms of the

 * GNU Lesser General Public License.

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <stdint.h>

#include <stddef.h>

#include "superblocks.h"

#define XENIX_NICINOD       100

#define XENIX_NICFREE       100

struct xenix_super_block {

  uint16_t  s_isize;

  uint32_t  s_fsize;

  uint16_t  s_nfree;

  uint32_t  s_free[XENIX_NICFREE];

  uint16_t  s_ninode;

  uint16_t  s_inode[XENIX_NICINOD];

  uint8_t   s_flock;

  uint8_t   s_ilock;

  uint8_t   s_fmod;

  uint8_t   s_ronly;

  uint32_t  s_time;

  uint32_t  s_tfree;

  uint16_t  s_tinode;

  uint16_t  s_dinfo[4];

  uint8_t   s_fname[6];

  uint8_t   s_fpack[6];

  uint8_t   s_clean;

  uint8_t   s_fill[371];

  uint32_t  s_magic;

  uint32_t  s_type;

} __attribute__((packed));

#define SYSV_NICINOD      100

#define SYSV_NICFREE      50

struct sysv_super_block

{

  uint16_t  s_isize;

  uint16_t  s_pad0;

  uint32_t  s_fsize;

  uint16_t  s_nfree;

  uint16_t  s_pad1;

  uint32_t  s_free[SYSV_NICFREE];

  uint16_t  s_ninode;

  uint16_t  s_pad2;

  uint16_t  s_inode[SYSV_NICINOD];

  uint8_t   s_flock;

  uint8_t   s_ilock;

  uint8_t   s_fmod;

  uint8_t   s_ronly;

  uint32_t  s_time;

  uint16_t  s_dinfo[4];

  uint32_t  s_tfree;

  uint16_t  s_tinode;

  uint16_t  s_pad3;

  uint8_t   s_fname[6];

  uint8_t   s_fpack[6];

  uint32_t  s_fill[12];

  uint32_t  s_state;

  uint32_t  s_magic;

  uint32_t  s_type;

};

static int probe_xenix(blkid_probe pr, const struct blkid_idmag *mag)

{

  const struct xenix_super_block *sb;

  sb = blkid_probe_get_sb(pr, mag, struct xenix_super_block);

  if (!sb)

    return errno ? -errno : 1;

  blkid_probe_set_label(pr, sb->s_fname, sizeof(sb->s_fname));

  return 0;

}

#define SYSV_BLOCK_SIZE 1024

/* Note that we don't probe for Coherent FS, this FS does not have

 * magic string. (It requires to probe fname/fpack field..)

 */

static int probe_sysv(blkid_probe pr,

    const struct blkid_idmag *mag __attribute__((__unused__)))

{

  struct sysv_super_block *sb;

  int blocks[] = {0, 9, 15, 18};

  size_t i;

  for (i = 0; i < ARRAY_SIZE(blocks); i++) {

    int off = blocks[i] * SYSV_BLOCK_SIZE + SYSV_BLOCK_SIZE/2;

    sb = (struct sysv_super_block *)

      blkid_probe_get_buffer(pr,

          off,

          sizeof(struct sysv_super_block));

    if (!sb)

      return errno ? -errno : 1;

    if (sb->s_magic == cpu_to_le32(0xfd187e20) ||

        sb->s_magic == cpu_to_be32(0xfd187e20)) {

      if (blkid_probe_set_label(pr, sb->s_fname,

            sizeof(sb->s_fname)))

        return 1;

      if (blkid_probe_set_magic(pr,

          off + offsetof(struct sysv_super_block,

                s_magic),

          sizeof(sb->s_magic),

          (unsigned char *) &sb->s_magic))

        return 1;

      return 0;

    }

  }

  return 1;

}

const struct blkid_idinfo xenix_idinfo =

{

  .name   = "xenix",

  .usage    = BLKID_USAGE_FILESYSTEM,

  .probefunc  = probe_xenix,

  .magics   =

  {

    { .magic = "\x2b\x55\x44", .len = 3, .kboff = 1, .sboff = 0x400 },

    { .magic = "\x44\x55\x2b", .len = 3, .kboff = 1, .sboff = 0x400 },

    { NULL }

  }

};

const struct blkid_idinfo sysv_idinfo =

{

  .name   = "sysv",

  .usage    = BLKID_USAGE_FILESYSTEM,

  .probefunc  = probe_sysv,

  /* SYSV is BE and LE, and superblock could be one of four positions.

   * So it's simpler to probe for the magic string via .probefunc().

   */

  .magics   = BLKID_NONE_MAGIC

};