/*      $OpenBSD: check.c,v 1.21 2021/07/12 15:09:18 beck Exp $ */
/*      $NetBSD: check.c,v 1.8 1997/10/17 11:19:29 ws Exp $     */

/*
 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
 * Copyright (c) 1995 Martin Husemann
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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/types.h>
#include <sys/ioctl.h>
#include <sys/dkio.h>
#include <sys/disklabel.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <stdio.h>
#include <unistd.h>
#include <limits.h>
#include <fcntl.h>
#include <util.h>
#include <err.h>

#include "ext.h"

struct disklabel lab;

int
checkfilesys(const char *fname)
{
        int dosfs;
        struct bootblock boot;
        struct fatEntry *fat = NULL;
        char *realdev;
        int i;
        int mod = 0;

        if (unveil("/dev", "rw") == -1)
                err(1, "unveil /dev");

        rdonly = alwaysno;

        dosfs = opendev(fname, rdonly ? O_RDONLY : O_RDWR, 0, &realdev);
        if (dosfs == -1 && !rdonly) {
                dosfs = opendev(fname, O_RDONLY, 0, &realdev);
                rdonly = 1;
        }
        if (dosfs == -1) {
                xperror("Can't open");
                return (8);
        }

        if (!preen) {
                printf("** %s", realdev);
                if (strncmp(fname, realdev, PATH_MAX) != 0)
                        printf(" (%s)", fname);
                if (rdonly)
                        printf(" (NO WRITE)");
                printf("\n");
        }

        if (ioctl(dosfs, DIOCGDINFO, (char *)&lab) == -1)
                pfatal("can't read disk label for %s\n", fname);

        if (pledge("stdio", NULL) == -1)
                err(1, "pledge");

        if (readboot(dosfs, &boot) != FSOK) {
                (void)close(dosfs);
                return (8);
        }

        if (!preen) {
                if (boot.ValidFat < 0)
                        printf("** Phase 1 - Read and Compare FATs\n");
                else
                        printf("** Phase 1 - Read FAT\n");
        }

        mod |= readfat(dosfs, &boot, boot.ValidFat >= 0 ? boot.ValidFat : 0, &fat);
        if (mod & FSFATAL) {
                (void)close(dosfs);
                return 8;
        }

        if (boot.ValidFat < 0)
                for (i = 1; i < boot.FATs; i++) {
                        struct fatEntry *currentFat;
                        mod |= readfat(dosfs, &boot, i, &currentFat);

                        if (mod & FSFATAL) {
                                free(fat);
                                (void)close(dosfs);
                                return 8;
                        }

                        mod |= comparefat(&boot, fat, currentFat, i);
                        free(currentFat);
                        if (mod & FSFATAL) {
                                free(fat);
                                (void)close(dosfs);
                                return (8);
                        }
                }

        if (!preen)
                printf("** Phase 2 - Check Cluster Chains\n");

        mod |= checkfat(&boot, fat);
        if (mod & FSFATAL) {
                free(fat);
                (void)close(dosfs);
                return (8);
        }

        if (mod & FSFATMOD)
                mod |= writefat(dosfs, &boot, fat); /* delay writing fats?      XXX */
        if (mod & FSFATAL) {
                free(fat);
                (void)close(dosfs);
                return (8);
        }

        if (!preen)
                printf("** Phase 3 - Check Directories\n");

        mod |= resetDosDirSection(&boot, fat);
        if (mod & FSFATAL) {
                free(fat);
                close(dosfs);
                return 8;
        }

        if (mod & FSFATMOD)
                mod |= writefat(dosfs, &boot, fat); /* delay writing fats?      XXX */
        if (mod & FSFATAL) {
                finishDosDirSection();
                free(fat);
                (void)close(dosfs);
                return (8);
        }

        mod |= handleDirTree(dosfs, &boot, fat);
        if (mod & FSFATAL) {
                finishDosDirSection();
                free(fat);
                (void)close(dosfs);
                return (8);
        }

        if (!preen)
                printf("** Phase 4 - Check for Lost Files\n");

        mod |= checklost(dosfs, &boot, fat);
        if (mod & FSFATAL) {
                finishDosDirSection();
                free(fat);
                (void)close(dosfs);
                return 8;
        }

        if (mod & FSFATMOD)
                mod |= writefat(dosfs, &boot, fat); /* delay writing fats?    XXX */

        finishDosDirSection();
        free(fat);
        (void)close(dosfs);
        if (mod & FSFATAL)
                return 8;

        if (boot.NumBad)
                pwarn("%d files, %d free (%d clusters), %d bad (%d clusters)\n",
                      boot.NumFiles,
                      boot.NumFree * boot.ClusterSize / 1024, boot.NumFree,
                      boot.NumBad * boot.ClusterSize / 1024, boot.NumBad);
        else
                pwarn("%d files, %d free (%d clusters)\n",
                      boot.NumFiles,
                      boot.NumFree * boot.ClusterSize / 1024, boot.NumFree);

        if (mod & (FSFATAL | FSERROR))
                return (8);
        if (mod) {
                pwarn("\n***** FILE SYSTEM WAS MODIFIED *****\n");
                return (4);
        }
        return (0);
}