/*
 * 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.
 *
 * @(#) Copyright (c) 1981, 1983, 1993 The Regents of the University of California.  All rights reserved.
 * @(#)badsect.c        8.1 (Berkeley) 6/5/93
 * $FreeBSD: src/sbin/badsect/badsect.c,v 1.7.2.2 2001/07/30 10:30:04 dd Exp $
 * $DragonFly: src/sbin/badsect/badsect.c,v 1.11 2006/04/03 01:58:46 dillon Exp $
 */

/*
 * 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/stat.h>

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

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

struct fs       sblock, *fs;
struct cg       acg;
int             fso, fsi;
int             errs;
long            dev_bsize = 1;

char            buf[MAXBSIZE];

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

static void
usage(void)
{
        fprintf(stderr, "usage: badsect bbdir blkno ...\n");
        exit(1);
}

int
main(int argc, char **argv)
{
        daddr_t diskbn;
        daddr_t number;
        dev_t dev;
        struct stat stbuf, devstat;
        struct dirent *dp;
        DIR *dirp;
        char name[2 * MAXPATHLEN];

        if (argc < 3)
                usage();
        if (chdir(argv[1]) < 0 || stat(".", &stbuf) < 0)
                err(2, "%s", argv[1]);
        if (strlcpy(name, _PATH_DEV, sizeof(name)) >= sizeof(name)) {
                errno = ENAMETOOLONG;   
                err(1, "cannot build path name");
        }
        if ((dirp = opendir(name)) == NULL)
                err(3, "%s", name);
        while ((dp = readdir(dirp)) != NULL) {
                strlcpy(name, _PATH_DEV, sizeof(name));
                if (strlcat(name, dp->d_name, sizeof(name)) >= sizeof(name)) {
                        errno = ENAMETOOLONG;   
                        err(1, "cannot build path name");
                }
                if (lstat(name, &devstat) < 0)
                        err(4, "%s", name);
                if (stbuf.st_dev == devstat.st_rdev &&
                    (devstat.st_mode & IFMT) == IFCHR)
                        break;
        }
        closedir(dirp);
        if (dp == NULL) {
                printf("Cannot find dev 0%lo corresponding to %s\n",
                    (u_long)stbuf.st_rdev, argv[1]);
                exit(5);
        }
        if ((fsi = open(name, O_RDONLY)) < 0)
                err(6, "%s", name);
        fs = &sblock;
        rdfs(SBOFF, SBSIZE, (char *)fs);
        dev_bsize = fs->fs_fsize / fsbtodb(fs, 1);
        for (argc -= 2, argv += 2; argc > 0; argc--, argv++) {
                number = atol(*argv);
                if (chkuse(number, 1))
                        continue;
                /*
                 * Print a warning if converting the block number to a dev_t
                 * will truncate it.  badsect was not very useful in versions
                 * of BSD before 4.4 because dev_t was 16 bits and another
                 * bit was lost by bogus sign extensions.
                 */
                diskbn = dbtofsb(fs, number);
                dev = (dev_t)diskbn;
                if ((daddr_t)dev != diskbn) {
                        printf("sector %ld cannot be represented as a dev_t\n",
                            (long)number);
                        errs++;
                } else if (mknod(*argv, IFMT | 0600, dev) < 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 (fs->fs_size < 0 || fsbn + cnt < 0) {
                printf("internal error: negative fs size or block number\n");
                return (1);
        }
        if (fsbn + cnt > fs->fs_size) {
                printf("block %ld out of range of file system\n", (long)blkno);
                return (1);
        }
        cg = dtog(fs, fsbn);
        if (fsbn < cgdmin(fs, cg)) {
                if (cg == 0 || (fsbn+cnt) > cgsblock(fs, cg)) {
                        printf("block %ld in non-data area: cannot attach\n",
                            (long)blkno);
                        return (1);
                }
        } else {
                if ((fsbn+cnt) > cgbase(fs, cg+1)) {
                        printf("block %ld in non-data area: cannot attach\n",
                            (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))
                printf("Warning: sector %ld is in use\n", (long)blkno);
        return (0);
}

/*
 * read a block from the file system
 */
static void
rdfs(daddr_t bno, int size, char *bf)
{
        int n;

        if (lseek(fsi, (off_t)bno * dev_bsize, SEEK_SET) < 0) {
                printf("seek error: %ld\n", (long)bno);
                err(1, "rdfs");
        }
        n = read(fsi, bf, size);
        if (n != size) {
                printf("read error: %ld\n", (long)bno);
                err(1, "rdfs");
        }
}