/*      $NetBSD: badsect.c,v 1.35 2022/11/17 06:40:38 chs Exp $ */

/*
 * Copyright (c) 1981, 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1981, 1983, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)badsect.c   8.2 (Berkeley) 5/4/95";
#else
__RCSID("$NetBSD: badsect.c,v 1.35 2022/11/17 06:40:38 chs Exp $");
#endif
#endif /* not lint */

/*
 * badsect
 *
 * Badsect takes a list of file-system relative sector numbers
 * and makes files containing the blocks of which these sectors are a part.
 * It can be used to contain sectors which have problems if these sectors
 * are not part of the bad file for the pack (see bad144).  For instance,
 * this program can be used if the driver for the file system in question
 * does not support bad block forwarding.
 */
#include <sys/param.h>
#include <sys/dir.h>
#include <sys/stat.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/ufs_bswap.h>
#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>

#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>

static union {
        struct  fs fs;
        char    fsx[SBLOCKSIZE];
} ufs;
#define sblock  ufs.fs
static union {
        struct  cg cg;
        char    cgx[MAXBSIZE];
} ucg;
#define acg     ucg.cg
static struct   fs *fs;
static int      fsi;
static int      errs;
static off_t    dev_bsize = 1;
static int needswap = 0;
static int is_ufs2;

static void     rdfs(off_t, size_t, void *);
static int      chkuse(daddr_t, int);

static const off_t sblock_try[] = SBLOCKSEARCH;

int
main(int argc, char *argv[])
{
        daddr_t number;
        struct stat stbuf, devstat;
        struct direct *dp;
        int i, did = 0;
        DIR *dirp;
        char name[MAXPATHLEN];
        size_t dl = sizeof(_PATH_DEV);

        if (argc < 3) {
                (void)fprintf(stderr, "usage: %s bbdir blkno [ blkno ]\n",
                    getprogname());
                exit(1);
        }
        if (chdir(argv[1]) == -1)
                err(1, "Cannot change directory to `%s'", argv[1]);

        if (stat(".", &stbuf) == -1)
                err(1, "Cannot stat `%s'", argv[1]);

        (void)strlcpy(name, _PATH_DEV, sizeof(name));
        if ((dirp = opendir(name)) == NULL)
                err(1, "Cannot opendir `%s'", argv[1]);

        while ((dp = readdir(dirp)) != NULL) {
                (void)strlcpy(name + dl - 1, dp->d_name, sizeof(name) - dl + 1);
                if (stat(name, &devstat) == -1)
                        err(1, "Cannot stat `%s'", name);
                if (stbuf.st_dev == devstat.st_rdev &&
                    S_ISBLK(devstat.st_mode))
                        break;
        }

        if (dp == NULL)
                errx(1, "Cannot find dev 0%llo corresponding to %s", 
                    (long long)stbuf.st_rdev, argv[1]);

        /*
         * The filesystem is mounted; use the character device instead.
         * XXX - Assume that prepending an `r' will give us the name of
         * the character device.
         */
        name[dl - 1] = 'r';
        (void)strlcpy(name + dl,  dp->d_name, sizeof(name) - dl);
        (void)closedir(dirp); /* now *dp is invalid */

        if ((fsi = open(name, O_RDONLY)) == -1)
                err(1, "Cannot open `%s'", argv[1]);

        fs = &sblock;

        for (i = 0; ; i++) {
                if (sblock_try[i] == -1)
                        errx(1, "%s: bad superblock", name);
                rdfs(sblock_try[i], SBLOCKSIZE, fs);
                switch (fs->fs_magic) {
                case FS_UFS2_MAGIC:
                case FS_UFS2EA_MAGIC:
                        is_ufs2 = 1;
                        /* FALLTHROUGH */
                case FS_UFS1_MAGIC:
                        break;
                case FS_UFS2_MAGIC_SWAPPED:
                case FS_UFS2EA_MAGIC_SWAPPED:
                        is_ufs2 = 1;
                        /* FALLTHROUGH */
                case FS_UFS1_MAGIC_SWAPPED:
                        needswap = 1;
                        ffs_sb_swap(fs, fs);
                        break;
                default:
                        continue;
                }

                /* Ensure we don't use 1st alternate if ffsv1 and bs=64k */
                if (is_ufs2 || fs->fs_old_flags & FS_FLAGS_UPDATED) {
                        if (fs->fs_sblockloc != sblock_try[i])
                                continue;
                } else {
                        if (sblock_try[i] == SBLOCK_UFS2)
                                continue;
                }
                break;
        }

        dev_bsize = fs->fs_fsize / FFS_FSBTODB(fs, 1);
        for (argc -= 2, argv += 2; argc > 0; argc--, argv++) {
                number = atoi(*argv);
                if (chkuse(number, 1))
                        continue;
                if (mknod(*argv, S_IFMT|S_IRUSR|S_IWUSR,
                    (dev_t)FFS_DBTOFSB(fs, number)) == -1) {
                        warn("Cannot mknod `%s'", *argv);
                        errs++;
                        continue;
                }
                did++;
        }

        if (did)
                warnx("Don't forget to run `fsck %s'", name);
        else
                warnx("File system `%s' was not modified", name);
        return errs;
}

static int
chkuse(off_t blkno, int cnt)
{
        int cg;
        off_t fsbn, bn, fsbe;

        fsbn = FFS_DBTOFSB(fs, blkno);
        fsbe = fsbn + cnt;
        if (fsbe > fs->fs_size) {
                warnx("block %lld out of range of file system",
                    (long long)blkno);
                return 1;
        }

        cg = (int)dtog(fs, fsbn);
        if (fsbn < cgdmin(fs, cg)) {
                if (cg == 0 || fsbe > cgsblock(fs, cg)) {
                        warnx("block %lld in superblock area: cannot attach",
                            (long long)blkno);
                        return 1;
                }
        } else {
                if (fsbe > cgbase(fs, cg + 1)) {
                        warnx("block %lld in beyond end of cylinder group: "
                            "cannot attach", (long long)blkno);
                        return 1;
                }
        }

        rdfs(FFS_FSBTODB(fs, cgtod(fs, cg)), (int)sblock.fs_cgsize, &acg);

        if (!cg_chkmagic(&acg, needswap)) {
                warnx("cg %d: bad magic number", cg);
                errs++;
                return 1;
        }

        bn = dtogd(fs, fsbn);
        if (isclr(cg_blksfree(&acg, needswap), bn))
                warnx("Warning: sector %lld is in use", (long long)blkno);

        return 0;
}

/*
 * read a block from the file system
 */
static void
rdfs(off_t bno, size_t size, void *bf)
{
        ssize_t n;

        if (lseek(fsi, bno * dev_bsize, SEEK_SET) == -1)
                err(1, "seek error at block %lld", (long long)bno);

        switch (n = read(fsi, bf, size)) {
        case -1:
                err(1, "read error at block %lld", (long long)bno);
                break;

        default:
                if ((size_t)n == size)
                        return;
                errx(1, "incomplete read at block %lld", (long long)bno);
        }
}