/* vi: set sw=4 ts=4: */
/*
 * probe.c - identify a block device by its contents, and return a dev
 *           struct with the details
 *
 * Copyright (C) 1999 by Andries Brouwer
 * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
 * Copyright (C) 2001 by Andreas Dilger
 *
 * %Begin-Header%
 * This file may be redistributed under the terms of the
 * GNU Lesser General Public License.
 * %End-Header%
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_SYS_MKDEV_H
#include <sys/mkdev.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include "blkidP.h"
#include "../uuid/uuid.h"
#include "probe.h"

/*
 * This is a special case code to check for an MDRAID device.  We do
 * this special since it requires checking for a superblock at the end
 * of the device.
 */
static int check_mdraid(int fd, unsigned char *ret_uuid)
{
        struct mdp_superblock_s *md;
        blkid_loff_t            offset;
        char                    buf[4096];

        if (fd < 0)
                return -BLKID_ERR_PARAM;

        offset = (blkid_get_dev_size(fd) & ~((blkid_loff_t)65535)) - 65536;

        if (blkid_llseek(fd, offset, 0) < 0 ||
            read(fd, buf, 4096) != 4096)
                return -BLKID_ERR_IO;

        /* Check for magic number */
        if (memcmp("\251+N\374", buf, 4))
                return -BLKID_ERR_PARAM;

        if (!ret_uuid)
                return 0;
        *ret_uuid = 0;

        /* The MD UUID is not contiguous in the superblock, make it so */
        md = (struct mdp_superblock_s *)buf;
        if (md->set_uuid0 || md->set_uuid1 || md->set_uuid2 || md->set_uuid3) {
                memcpy(ret_uuid, &md->set_uuid0, 4);
                memcpy(ret_uuid, &md->set_uuid1, 12);
        }
        return 0;
}

static void set_uuid(blkid_dev dev, uuid_t uuid)
{
        char    str[37];

        if (!uuid_is_null(uuid)) {
                uuid_unparse(uuid, str);
                blkid_set_tag(dev, "UUID", str, sizeof(str));
        }
}

static void get_ext2_info(blkid_dev dev, unsigned char *buf)
{
        struct ext2_super_block *es = (struct ext2_super_block *) buf;
        const char *label = 0;

        DBG(DEBUG_PROBE, printf("ext2_sb.compat = %08X:%08X:%08X\n",
                   blkid_le32(es->s_feature_compat),
                   blkid_le32(es->s_feature_incompat),
                   blkid_le32(es->s_feature_ro_compat)));

        if (strlen(es->s_volume_name))
                label = es->s_volume_name;
        blkid_set_tag(dev, "LABEL", label, sizeof(es->s_volume_name));

        set_uuid(dev, es->s_uuid);
}

static int probe_ext3(int fd __BLKID_ATTR((unused)),
                      blkid_cache cache __BLKID_ATTR((unused)),
                      blkid_dev dev,
                      const struct blkid_magic *id __BLKID_ATTR((unused)),
                      unsigned char *buf)
{
        struct ext2_super_block *es;

        es = (struct ext2_super_block *)buf;

        /* Distinguish between jbd and ext2/3 fs */
        if (blkid_le32(es->s_feature_incompat) &
            EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
                return -BLKID_ERR_PARAM;

        /* Distinguish between ext3 and ext2 */
        if (!(blkid_le32(es->s_feature_compat) &
              EXT3_FEATURE_COMPAT_HAS_JOURNAL))
                return -BLKID_ERR_PARAM;

        get_ext2_info(dev, buf);

        blkid_set_tag(dev, "SEC_TYPE", "ext2", sizeof("ext2"));

        return 0;
}

static int probe_ext2(int fd __BLKID_ATTR((unused)),
                      blkid_cache cache __BLKID_ATTR((unused)),
                      blkid_dev dev,
                      const struct blkid_magic *id __BLKID_ATTR((unused)),
                      unsigned char *buf)
{
        struct ext2_super_block *es;

        es = (struct ext2_super_block *)buf;

        /* Distinguish between jbd and ext2/3 fs */
        if (blkid_le32(es->s_feature_incompat) &
            EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
                return -BLKID_ERR_PARAM;

        get_ext2_info(dev, buf);

        return 0;
}

static int probe_jbd(int fd __BLKID_ATTR((unused)),
                     blkid_cache cache __BLKID_ATTR((unused)),
                     blkid_dev dev,
                     const struct blkid_magic *id __BLKID_ATTR((unused)),
                     unsigned char *buf)
{
        struct ext2_super_block *es = (struct ext2_super_block *) buf;

        if (!(blkid_le32(es->s_feature_incompat) &
              EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
                return -BLKID_ERR_PARAM;

        get_ext2_info(dev, buf);

        return 0;
}

static int probe_vfat(int fd __BLKID_ATTR((unused)),
                      blkid_cache cache __BLKID_ATTR((unused)),
                      blkid_dev dev,
                      const struct blkid_magic *id __BLKID_ATTR((unused)),
                      unsigned char *buf)
{
        struct vfat_super_block *vs;
        char serno[10];
        const char *label = 0;
        int label_len = 0;

        vs = (struct vfat_super_block *)buf;

        if (strncmp(vs->vs_label, "NO NAME", 7)) {
                char *end = vs->vs_label + sizeof(vs->vs_label) - 1;

                while (*end == ' ' && end >= vs->vs_label)
                        --end;
                if (end >= vs->vs_label) {
                        label = vs->vs_label;
                        label_len = end - vs->vs_label + 1;
                }
        }

        /* We can't just print them as %04X, because they are unaligned */
        sprintf(serno, "%02X%02X-%02X%02X", vs->vs_serno[3], vs->vs_serno[2],
                vs->vs_serno[1], vs->vs_serno[0]);
        blkid_set_tag(dev, "LABEL", label, label_len);
        blkid_set_tag(dev, "UUID", serno, sizeof(serno));

        return 0;
}

static int probe_msdos(int fd __BLKID_ATTR((unused)),
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf)
{
        struct msdos_super_block *ms = (struct msdos_super_block *) buf;
        char serno[10];
        const char *label = 0;
        int label_len = 0;

        if (strncmp(ms->ms_label, "NO NAME", 7)) {
                char *end = ms->ms_label + sizeof(ms->ms_label) - 1;

                while (*end == ' ' && end >= ms->ms_label)
                        --end;
                if (end >= ms->ms_label) {
                        label = ms->ms_label;
                        label_len = end - ms->ms_label + 1;
                }
        }

        /* We can't just print them as %04X, because they are unaligned */
        sprintf(serno, "%02X%02X-%02X%02X", ms->ms_serno[3], ms->ms_serno[2],
                ms->ms_serno[1], ms->ms_serno[0]);
        blkid_set_tag(dev, "UUID", serno, 0);
        blkid_set_tag(dev, "LABEL", label, label_len);
        blkid_set_tag(dev, "SEC_TYPE", "msdos", sizeof("msdos"));

        return 0;
}

static int probe_xfs(int fd __BLKID_ATTR((unused)),
                     blkid_cache cache __BLKID_ATTR((unused)),
                     blkid_dev dev,
                     const struct blkid_magic *id __BLKID_ATTR((unused)),
                     unsigned char *buf)
{
        struct xfs_super_block *xs;
        const char *label = 0;

        xs = (struct xfs_super_block *)buf;

        if (strlen(xs->xs_fname))
                label = xs->xs_fname;
        blkid_set_tag(dev, "LABEL", label, sizeof(xs->xs_fname));
        set_uuid(dev, xs->xs_uuid);
        return 0;
}

static int probe_reiserfs(int fd __BLKID_ATTR((unused)),
                          blkid_cache cache __BLKID_ATTR((unused)),
                          blkid_dev dev,
                          const struct blkid_magic *id, unsigned char *buf)
{
        struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
        unsigned int blocksize;
        const char *label = 0;

        blocksize = blkid_le16(rs->rs_blocksize);

        /* If the superblock is inside the journal, we have the wrong one */
        if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
                return -BLKID_ERR_BIG;

        /* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
        if (!strcmp(id->bim_magic, "ReIsEr2Fs") ||
            !strcmp(id->bim_magic, "ReIsEr3Fs")) {
                if (strlen(rs->rs_label))
                        label = rs->rs_label;
                set_uuid(dev, rs->rs_uuid);
        }
        blkid_set_tag(dev, "LABEL", label, sizeof(rs->rs_label));

        return 0;
}

static int probe_jfs(int fd __BLKID_ATTR((unused)),
                     blkid_cache cache __BLKID_ATTR((unused)),
                     blkid_dev dev,
                     const struct blkid_magic *id __BLKID_ATTR((unused)),
                     unsigned char *buf)
{
        struct jfs_super_block *js;
        const char *label = 0;

        js = (struct jfs_super_block *)buf;

        if (strlen((char *) js->js_label))
                label = (char *) js->js_label;
        blkid_set_tag(dev, "LABEL", label, sizeof(js->js_label));
        set_uuid(dev, js->js_uuid);
        return 0;
}

static int probe_romfs(int fd __BLKID_ATTR((unused)),
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf)
{
        struct romfs_super_block *ros;
        const char *label = 0;

        ros = (struct romfs_super_block *)buf;

        if (strlen((char *) ros->ros_volume))
                label = (char *) ros->ros_volume;
        blkid_set_tag(dev, "LABEL", label, 0);
        return 0;
}

static int probe_cramfs(int fd __BLKID_ATTR((unused)),
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf)
{
        struct cramfs_super_block *csb;
        const char *label = 0;

        csb = (struct cramfs_super_block *)buf;

        if (strlen((char *) csb->name))
                label = (char *) csb->name;
        blkid_set_tag(dev, "LABEL", label, 0);
        return 0;
}

static int probe_swap0(int fd __BLKID_ATTR((unused)),
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf __BLKID_ATTR((unused)))
{
        blkid_set_tag(dev, "UUID", 0, 0);
        blkid_set_tag(dev, "LABEL", 0, 0);
        return 0;
}

static int probe_swap1(int fd,
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf __BLKID_ATTR((unused)))
{
        struct swap_id_block *sws;

        probe_swap0(fd, cache, dev, id, buf);
        /*
         * Version 1 swap headers are always located at offset of 1024
         * bytes, although the swap signature itself is located at the
         * end of the page (which may vary depending on hardware
         * pagesize).
         */
        if (lseek(fd, 1024, SEEK_SET) < 0) return 1;
        sws = xmalloc(1024);
        if (read(fd, sws, 1024) != 1024) {
                free(sws);
                return 1;
        }

        /* arbitrary sanity check.. is there any garbage down there? */
        if (sws->sws_pad[32] == 0 && sws->sws_pad[33] == 0)  {
                if (sws->sws_volume[0])
                        blkid_set_tag(dev, "LABEL", (const char*)sws->sws_volume,
                                      sizeof(sws->sws_volume));
                if (sws->sws_uuid[0])
                        set_uuid(dev, sws->sws_uuid);
        }
        free(sws);

        return 0;
}

static const char
* const udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
                 "NSR03", "TEA01", 0 };

static int probe_udf(int fd, blkid_cache cache __BLKID_ATTR((unused)),
                     blkid_dev dev __BLKID_ATTR((unused)),
                     const struct blkid_magic *id __BLKID_ATTR((unused)),
                     unsigned char *buf __BLKID_ATTR((unused)))
{
        int j, bs;
        struct iso_volume_descriptor isosb;
        const char *const *m;

        /* determine the block size by scanning in 2K increments
           (block sizes larger than 2K will be null padded) */
        for (bs = 1; bs < 16; bs++) {
                lseek(fd, bs*2048+32768, SEEK_SET);
                if (read(fd, (char *)&isosb, sizeof(isosb)) != sizeof(isosb))
                        return 1;
                if (isosb.id[0])
                        break;
        }

        /* Scan up to another 64 blocks looking for additional VSD's */
        for (j = 1; j < 64; j++) {
                if (j > 1) {
                        lseek(fd, j*bs*2048+32768, SEEK_SET);
                        if (read(fd, (char *)&isosb, sizeof(isosb))
                            != sizeof(isosb))
                                return 1;
                }
                /* If we find NSR0x then call it udf:
                   NSR01 for UDF 1.00
                   NSR02 for UDF 1.50
                   NSR03 for UDF 2.00 */
                if (!strncmp(isosb.id, "NSR0", 4))
                        return 0;
                for (m = udf_magic; *m; m++)
                        if (!strncmp(*m, isosb.id, 5))
                                break;
                if (*m == 0)
                        return 1;
        }
        return 1;
}

static int probe_ocfs(int fd __BLKID_ATTR((unused)),
                      blkid_cache cache __BLKID_ATTR((unused)),
                      blkid_dev dev,
                      const struct blkid_magic *id __BLKID_ATTR((unused)),
                      unsigned char *buf)
{
        struct ocfs_volume_header ovh;
        struct ocfs_volume_label ovl;
        __u32 major;

        memcpy(&ovh, buf, sizeof(ovh));
        memcpy(&ovl, buf+512, sizeof(ovl));

        major = ocfsmajor(ovh);
        if (major == 1)
                blkid_set_tag(dev, "SEC_TYPE", "ocfs1", sizeof("ocfs1"));
        else if (major >= 9)
                blkid_set_tag(dev, "SEC_TYPE", "ntocfs", sizeof("ntocfs"));

        blkid_set_tag(dev, "LABEL", (const char*)ovl.label, ocfslabellen(ovl));
        blkid_set_tag(dev, "MOUNT", (const char*)ovh.mount, ocfsmountlen(ovh));
        set_uuid(dev, ovl.vol_id);
        return 0;
}

static int probe_ocfs2(int fd __BLKID_ATTR((unused)),
                       blkid_cache cache __BLKID_ATTR((unused)),
                       blkid_dev dev,
                       const struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf)
{
        struct ocfs2_super_block *osb;

        osb = (struct ocfs2_super_block *)buf;

        blkid_set_tag(dev, "LABEL", (const char*)osb->s_label, sizeof(osb->s_label));
        set_uuid(dev, osb->s_uuid);
        return 0;
}

static int probe_oracleasm(int fd __BLKID_ATTR((unused)),
                           blkid_cache cache __BLKID_ATTR((unused)),
                           blkid_dev dev,
                           const struct blkid_magic *id __BLKID_ATTR((unused)),
                           unsigned char *buf)
{
        struct oracle_asm_disk_label *dl;

        dl = (struct oracle_asm_disk_label *)buf;

        blkid_set_tag(dev, "LABEL", dl->dl_id, sizeof(dl->dl_id));
        return 0;
}

/*
 * BLKID_BLK_OFFS is at least as large as the highest bim_kboff defined
 * in the type_array table below + bim_kbalign.
 *
 * When probing for a lot of magics, we handle everything in 1kB buffers so
 * that we don't have to worry about reading each combination of block sizes.
 */
#define BLKID_BLK_OFFS  64      /* currently reiserfs */

/*
 * Various filesystem magics that we can check for.  Note that kboff and
 * sboff are in kilobytes and bytes respectively.  All magics are in
 * byte strings so we don't worry about endian issues.
 */
static const struct blkid_magic type_array[] = {
/*  type     kboff   sboff len  magic                   probe */
  { "oracleasm", 0,     32,  8, "ORCLDISK",             probe_oracleasm },
  { "ntfs",      0,      3,  8, "NTFS    ",             0 },
  { "jbd",       1,   0x38,  2, "\123\357",             probe_jbd },
  { "ext3",      1,   0x38,  2, "\123\357",             probe_ext3 },
  { "ext2",      1,   0x38,  2, "\123\357",             probe_ext2 },
  { "reiserfs",  8,   0x34,  8, "ReIsErFs",             probe_reiserfs },
  { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",            probe_reiserfs },
  { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",            probe_reiserfs },
  { "reiserfs", 64,   0x34,  8, "ReIsErFs",             probe_reiserfs },
  { "reiserfs",  8,     20,  8, "ReIsErFs",             probe_reiserfs },
  { "vfat",      0,   0x52,  5, "MSWIN",                probe_vfat },
  { "vfat",      0,   0x52,  8, "FAT32   ",             probe_vfat },
  { "vfat",      0,   0x36,  5, "MSDOS",                probe_msdos },
  { "vfat",      0,   0x36,  8, "FAT16   ",             probe_msdos },
  { "vfat",      0,   0x36,  8, "FAT12   ",             probe_msdos },
  { "minix",     1,   0x10,  2, "\177\023",             0 },
  { "minix",     1,   0x10,  2, "\217\023",             0 },
  { "minix",     1,   0x10,  2, "\150\044",             0 },
  { "minix",     1,   0x10,  2, "\170\044",             0 },
  { "vxfs",      1,      0,  4, "\365\374\001\245",     0 },
  { "xfs",       0,      0,  4, "XFSB",                 probe_xfs },
  { "romfs",     0,      0,  8, "-rom1fs-",             probe_romfs },
  { "bfs",       0,      0,  4, "\316\372\173\033",     0 },
  { "cramfs",    0,      0,  4, "E=\315\050",           probe_cramfs },
  { "qnx4",      0,      4,  6, "QNX4FS",               0 },
  { "udf",      32,      1,  5, "BEA01",                probe_udf },
  { "udf",      32,      1,  5, "BOOT2",                probe_udf },
  { "udf",      32,      1,  5, "CD001",                probe_udf },
  { "udf",      32,      1,  5, "CDW02",                probe_udf },
  { "udf",      32,      1,  5, "NSR02",                probe_udf },
  { "udf",      32,      1,  5, "NSR03",                probe_udf },
  { "udf",      32,      1,  5, "TEA01",                probe_udf },
  { "iso9660",  32,      1,  5, "CD001",                0 },
  { "iso9660",  32,      9,  5, "CDROM",                0 },
  { "jfs",      32,      0,  4, "JFS1",                 probe_jfs },
  { "hfs",       1,      0,  2, "BD",                   0 },
  { "ufs",       8,  0x55c,  4, "T\031\001\000",        0 },
  { "hpfs",      8,      0,  4, "I\350\225\371",        0 },
  { "sysv",      0,  0x3f8,  4, "\020~\030\375",        0 },
  { "swap",      0,  0xff6, 10, "SWAP-SPACE",           probe_swap0 },
  { "swap",      0,  0xff6, 10, "SWAPSPACE2",           probe_swap1 },
  { "swap",      0, 0x1ff6, 10, "SWAP-SPACE",           probe_swap0 },
  { "swap",      0, 0x1ff6, 10, "SWAPSPACE2",           probe_swap1 },
  { "swap",      0, 0x3ff6, 10, "SWAP-SPACE",           probe_swap0 },
  { "swap",      0, 0x3ff6, 10, "SWAPSPACE2",           probe_swap1 },
  { "swap",      0, 0x7ff6, 10, "SWAP-SPACE",           probe_swap0 },
  { "swap",      0, 0x7ff6, 10, "SWAPSPACE2",           probe_swap1 },
  { "swap",      0, 0xfff6, 10, "SWAP-SPACE",           probe_swap0 },
  { "swap",      0, 0xfff6, 10, "SWAPSPACE2",           probe_swap1 },
  { "ocfs",      0,      8,  9, "OracleCFS",            probe_ocfs },
  { "ocfs2",     1,      0,  6, "OCFSV2",               probe_ocfs2 },
  { "ocfs2",     2,      0,  6, "OCFSV2",               probe_ocfs2 },
  { "ocfs2",     4,      0,  6, "OCFSV2",               probe_ocfs2 },
  { "ocfs2",     8,      0,  6, "OCFSV2",               probe_ocfs2 },
  {   NULL,      0,      0,  0, NULL,                   NULL }
};

/*
 * Verify that the data in dev is consistent with what is on the actual
 * block device (using the devname field only).  Normally this will be
 * called when finding items in the cache, but for long running processes
 * is also desirable to revalidate an item before use.
 *
 * If we are unable to revalidate the data, we return the old data and
 * do not set the BLKID_BID_FL_VERIFIED flag on it.
 */
blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
{
        const struct blkid_magic *id;
        unsigned char *bufs[BLKID_BLK_OFFS + 1], *buf;
        const char *type;
        struct stat st;
        time_t diff, now;
        int fd, idx;

        if (!dev)
                return NULL;

        now = time(0);
        diff = now - dev->bid_time;

        if ((now < dev->bid_time) ||
            (diff < BLKID_PROBE_MIN) ||
            (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
             diff < BLKID_PROBE_INTERVAL))
                return dev;

        DBG(DEBUG_PROBE,
            printf("need to revalidate %s (time since last check %lu)\n",
                   dev->bid_name, diff));

        if (((fd = open(dev->bid_name, O_RDONLY)) < 0) ||
            (fstat(fd, &st) < 0)) {
                if (errno == ENXIO || errno == ENODEV || errno == ENOENT) {
                        blkid_free_dev(dev);
                        return NULL;
                }
                /* We don't have read permission, just return cache data. */
                DBG(DEBUG_PROBE,
                    printf("returning unverified data for %s\n",
                           dev->bid_name));
                return dev;
        }

        memset(bufs, 0, sizeof(bufs));

        /*
         * Iterate over the type array.  If we already know the type,
         * then try that first.  If it doesn't work, then blow away
         * the type information, and try again.
         *
         */
try_again:
        type = 0;
        if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
                uuid_t  uuid;

                if (check_mdraid(fd, uuid) == 0) {
                        set_uuid(dev, uuid);
                        type = "mdraid";
                        goto found_type;
                }
        }
        for (id = type_array; id->bim_type; id++) {
                if (dev->bid_type &&
                    strcmp(id->bim_type, dev->bid_type))
                        continue;

                idx = id->bim_kboff + (id->bim_sboff >> 10);
                if (idx > BLKID_BLK_OFFS || idx < 0)
                        continue;
                buf = bufs[idx];
                if (!buf) {
                        if (lseek(fd, idx << 10, SEEK_SET) < 0)
                                continue;

                        buf = xmalloc(1024);

                        if (read(fd, buf, 1024) != 1024) {
                                free(buf);
                                continue;
                        }
                        bufs[idx] = buf;
                }

                if (memcmp(id->bim_magic, buf + (id->bim_sboff&0x3ff),
                           id->bim_len))
                        continue;

                if ((id->bim_probe == NULL) ||
                    (id->bim_probe(fd, cache, dev, id, buf) == 0)) {
                        type = id->bim_type;
                        goto found_type;
                }
        }

        if (!id->bim_type && dev->bid_type) {
                /*
                 * Zap the device filesystem type and try again
                 */
                blkid_set_tag(dev, "TYPE", 0, 0);
                blkid_set_tag(dev, "SEC_TYPE", 0, 0);
                blkid_set_tag(dev, "LABEL", 0, 0);
                blkid_set_tag(dev, "UUID", 0, 0);
                goto try_again;
        }

        if (!dev->bid_type) {
                blkid_free_dev(dev);
                return NULL;
        }

found_type:
        if (dev && type) {
                dev->bid_devno = st.st_rdev;
                dev->bid_time = time(0);
                dev->bid_flags |= BLKID_BID_FL_VERIFIED;
                cache->bic_flags |= BLKID_BIC_FL_CHANGED;

                blkid_set_tag(dev, "TYPE", type, 0);

                DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
                           dev->bid_name, st.st_rdev, type));
        }

        close(fd);

        return dev;
}

int blkid_known_fstype(const char *fstype)
{
        const struct blkid_magic *id;

        for (id = type_array; id->bim_type; id++) {
                if (strcmp(fstype, id->bim_type) == 0)
                        return 1;
        }
        return 0;
}

#ifdef TEST_PROGRAM
int main(int argc, char **argv)
{
        blkid_dev dev;
        blkid_cache cache;
        int ret;

        blkid_debug_mask = DEBUG_ALL;
        if (argc != 2) {
                fprintf(stderr, "Usage: %s device\n"
                        "Probe a single device to determine type\n", argv[0]);
                exit(1);
        }
        if ((ret = blkid_get_cache(&cache, bb_dev_null)) != 0) {
                fprintf(stderr, "%s: error creating cache (%d)\n",
                        argv[0], ret);
                exit(1);
        }
        dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
        if (!dev) {
                printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
                return 1;
        }
        printf("%s is type %s\n", argv[1], dev->bid_type ?
                dev->bid_type : "(null)");
        if (dev->bid_label)
                printf("\tlabel is '%s'\n", dev->bid_label);
        if (dev->bid_uuid)
                printf("\tuuid is %s\n", dev->bid_uuid);

        blkid_free_dev(dev);
        return 0;
}
#endif