/*      $NetBSD: check.c,v 1.20 2022/08/28 10:20:25 mlelstv 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/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: check.c,v 1.20 2022/08/28 10:20:25 mlelstv Exp $");
#endif /* not lint */

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

#include "ext.h"
#include "fsutil.h"
#include "exitvalues.h"

int
checkfilesys(const char *filename)
{
        int dosfs;
        struct bootblock boot;
        struct fatEntry *fat = NULL;
        int finish_dosdirsection=0;
        u_int i;
        int mod = 0;
        int ret = FSCK_EXIT_CHECK_FAILED;

        rdonly = alwaysno;
        if (!preen)
                printf("** %s", filename);

        dosfs = open(filename, rdonly ? O_RDONLY : O_RDWR, 0);
        if (dosfs < 0 && !rdonly) {
                dosfs = open(filename, O_RDONLY, 0);
                if (dosfs >= 0)
                        pwarn(" (NO WRITE)\n");
                else if (!preen)
                        printf("\n");
                rdonly = 1;
        } else if (!preen)
                printf("\n");

        if (dosfs < 0) {
                perr("Can't open `%s'", filename);
                return FSCK_EXIT_CHECK_FAILED;
        }

        mod = readboot(dosfs, &boot);
        if (mod & FSFATAL) {
                close(dosfs);
                printf("\n");
                return FSCK_EXIT_CHECK_FAILED;
        }

        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) {
                close(dosfs);
                return FSCK_EXIT_CHECK_FAILED;
        }

        if (boot.ValidFat < 0)
                for (i = 1; i < boot.FATs; i++) {
                        struct fatEntry *currentFat;

                        mod |= readfat(dosfs, &boot, i, &currentFat);

                        if (mod & FSFATAL)
                                goto out;

                        mod |= comparefat(&boot, fat, currentFat, i);
                        free(currentFat);
                        if (mod & FSFATAL)
                                goto out;
                }

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

        mod |= checkfat(&boot, fat);
        if (mod & FSFATAL)
                goto out;
        /* delay writing FATs */

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

        mod |= resetDosDirSection(&boot, fat);
        finish_dosdirsection = 1;
        if (mod & FSFATAL)
                goto out;
        /* delay writing FATs */

        mod |= handleDirTree(dosfs, &boot, fat);
        if (mod & FSFATAL)
                goto out;

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

        mod |= checklost(dosfs, &boot, fat);
        if (mod & FSFATAL)
                goto out;

        /* now write the FATs */
        if (mod & (FSFATMOD|FSFIXFAT)) {
                if (ask(1, "Update FATs")) {
                        mod |= writefat(dosfs, &boot, fat, mod & FSFIXFAT);
                        if (mod & FSFATAL)
                                goto out;
                } else
                        mod |= FSERROR;
        }

        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 && (mod & FSERROR) == 0) {
                if (mod & FSDIRTY) {
                        if (ask(1, "MARK FILE SYSTEM CLEAN") == 0)
                                mod &= ~FSDIRTY;

                        if (mod & FSDIRTY) {
                                pwarn("MARKING FILE SYSTEM CLEAN\n");
                                mod |= writefat(dosfs, &boot, fat, 1);
                        } else {
                                pwarn("\n***** FILE SYSTEM IS LEFT MARKED AS DIRTY *****\n");
                                mod |= FSERROR; /* file system not clean */
                        }
                }
        }

        if (mod & (FSFATAL | FSERROR))
                goto out;

        ret = FSCK_EXIT_OK;

    out:
        if (finish_dosdirsection)
                finishDosDirSection();
        free(fat);
        close(dosfs);

        if (mod & (FSFATMOD|FSDIRMOD))
                pwarn("\n***** FILE SYSTEM WAS MODIFIED *****\n");

        return ret;
}