/*      $OpenBSD: badsect.c,v 1.29 2022/10/12 23:11:32 krw Exp $        */
/*      $NetBSD: badsect.c,v 1.10 1995/03/18 14:54:28 cgd 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.
 */

/*
 * 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. 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>  /* MAXBSIZE DEV_BSIZE isclr */
#include <sys/stat.h>

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

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

static int chkuse(daddr_t, int);
static void rdfs(daddr_t, int, char *);

static union {
        struct  fs fs;
        char    fsx[SBSIZE];
} 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;

int
main(int argc, char *argv[])
{
        daddr_t number;
        struct stat stbuf, devstat;
        struct dirent *dp;
        DIR *dirp;
        char name[BUFSIZ];
        int len;

        if (argc < 3) {
                fprintf(stderr, "usage: badsect bbdir sector ...\n");
                exit(1);
        }
        if (chdir(argv[1]) == -1 || stat(".", &stbuf) == -1)
                err(2, "%s", argv[1]);

        strlcpy(name, _PATH_DEV, sizeof name);
        len = strlen(name);
        if ((dirp = opendir(name)) == NULL)
                err(3, "%s", name);

        while ((dp = readdir(dirp)) != NULL) {
                strlcpy(&name[len], dp->d_name, sizeof name - len);
                if (stat(name, &devstat) == -1)
                        err(4, "%s", name);

                if (stbuf.st_dev == devstat.st_rdev &&
                    S_ISBLK(devstat.st_mode))
                        break;
        }

        /*
         * We've found the block device, but since the filesystem
         * is mounted, we must write to the raw (character) device
         * instead. This is not guaranteed to work if someone has a
         * /dev that doesn't follow standard naming conventions, but
         * it's all we've got.
         */
        name[len] = 'r';
        strlcpy(&name[len+1], dp->d_name, sizeof name - (len+1));
        closedir(dirp);
        if (dp == NULL)
                err(5, "Cannot find dev 0%o corresponding to %s",
                        stbuf.st_rdev, argv[1]);

        if ((fsi = open(name, O_RDONLY)) == -1)
                err(6, "%s", name);

        fs = &sblock;
        rdfs(SBOFF, SBSIZE, (char *)fs);
        for (argc -= 2, argv += 2; argc > 0; argc--, argv++) {
                number = strtonum(*argv, 0, QUAD_MAX, NULL);
                if (chkuse(number, 1))
                        continue;
                if (mknod(*argv, S_IFMT|S_IRUSR|S_IWUSR,
                    dbtofsb(fs, number)) < 0) {
                        warn("%s", *argv);
                        errs++;
                }
        }
        printf("Don't forget to run ``fsck %s''\n", name);
        exit(errs);
}

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

        fsbn = dbtofsb(fs, blkno);
        if (fsbn+cnt > fs->fs_ffs1_size) {
                fprintf(stderr, "block %lld out of range of file system\n",
                    (long long)blkno);
                return (1);
        }
        cg = dtog(fs, fsbn);
        if (fsbn < cgdmin(fs, cg)) {
                if (cg == 0 || (fsbn+cnt) > cgsblock(fs, cg)) {
                        fprintf(stderr, "block %lld in non-data area: cannot "
                            "attach\n", (long long)blkno);
                        return (1);
                }
        } else {
                if ((fsbn+cnt) > cgbase(fs, cg+1)) {
                        fprintf(stderr, "block %lld in non-data area: cannot "
                            "attach\n", (long long)blkno);
                        return (1);
                }
        }
        rdfs(fsbtodb(fs, cgtod(fs, cg)), (int)sblock.fs_cgsize,
            (char *)&acg);
        if (!cg_chkmagic(&acg)) {
                fprintf(stderr, "cg %d: bad magic number\n", cg);
                errs++;
                return (1);
        }
        bn = dtogd(fs, fsbn);
        if (isclr(cg_blksfree(&acg), bn))
                fprintf(stderr, "Warning: sector %lld is in use\n",
                    (long long)blkno);
        return (0);
}

/*
 * read a block from the file system
 */
static void
rdfs(daddr_t bno, int size, char *bf)
{
        if (pread(fsi, bf, size, bno * DEV_BSIZE) != size) {
                fprintf(stderr, "read error: %lld\n", (long long)bno);
                err(1, "rdfs");
        }
}