/*      $OpenBSD: utilities.c,v 1.29 2023/03/08 04:43:06 guenther Exp $ */
/*      $NetBSD: utilities.c,v 1.6 2001/02/04 21:19:34 christos Exp $   */

/*
 * Copyright (c) 1997 Manuel Bouyer.
 * Copyright (c) 1980, 1986, 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/param.h>  /* DEV_BSIZE isset setbit */
#include <sys/time.h>
#include <sys/signal.h>
#include <ufs/ext2fs/ext2fs_dinode.h>
#include <ufs/ext2fs/ext2fs_dir.h>
#include <ufs/ext2fs/ext2fs.h>
#include <ufs/ufs/dinode.h> /* for IFMT & friends */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <errno.h>

#include "fsutil.h"
#include "fsck.h"
#include "extern.h"

long    diskreads, totalreads;  /* Disk cache statistics */

static void rwerror(char *, daddr32_t);

int
ftypeok(struct ext2fs_dinode *dp)
{
        switch (letoh16(dp->e2di_mode) & IFMT) {

        case IFDIR:
        case IFREG:
        case IFBLK:
        case IFCHR:
        case IFLNK:
        case IFSOCK:
        case IFIFO:
                return (1);

        default:
                if (debug)
                        printf("bad file type 0%o\n", letoh16(dp->e2di_mode));
                return (0);
        }
}

int
reply(char *question)
{
        int persevere;
        int c;

        if (preen)
                pfatal("INTERNAL ERROR: GOT TO reply()");
        persevere = !strcmp(question, "CONTINUE");
        printf("\n");
        if (!persevere && (nflag || fswritefd < 0)) {
                printf("%s? no\n\n", question);
                return (0);
        }
        if (yflag || (persevere && nflag)) {
                printf("%s? yes\n\n", question);
                return (1);
        }
        do {
                printf("%s? [Fyn?] ", question);
                (void) fflush(stdout);
                c = getc(stdin);
                if (c == 'F') {
                        yflag = 1;
                        return (1);
                }
                while (c != '\n' && getc(stdin) != '\n')
                        if (feof(stdin))
                                return (0);
        } while (c != 'y' && c != 'Y' && c != 'n' && c != 'N');
        printf("\n");
        if (c == 'y' || c == 'Y')
                return (1);
        return (0);
}

/*
 * Malloc buffers and set up cache.
 */
void
bufinit(void)
{
        struct bufarea *bp;
        long bufcnt, i;
        char *bufp;

        diskreads = totalreads = 0;
        pbp = pdirbp = NULL;
        bufhead.b_next = bufhead.b_prev = &bufhead;
        bufcnt = MAXBUFSPACE / sblock.e2fs_bsize;
        if (bufcnt < MINBUFS)
                bufcnt = MINBUFS;
        for (i = 0; i < bufcnt; i++) {
                bp = malloc(sizeof(struct bufarea));
                bufp = malloc((unsigned int)sblock.e2fs_bsize);
                if (bp == NULL || bufp == NULL) {
                        free(bp);
                        free(bufp);
                        if (i >= MINBUFS)
                                break;
                        errexit("cannot allocate buffer pool\n");
                }
                bp->b_un.b_buf = bufp;
                bp->b_prev = &bufhead;
                bp->b_next = bufhead.b_next;
                bufhead.b_next->b_prev = bp;
                bufhead.b_next = bp;
                initbarea(bp);
        }
        bufhead.b_size = i;     /* save number of buffers */
}

/*
 * Manage a cache of directory blocks.
 */
struct bufarea *
getdatablk(daddr32_t blkno, long size)
{
        struct bufarea *bp;

        for (bp = bufhead.b_next; bp != &bufhead; bp = bp->b_next)
                if (bp->b_bno == fsbtodb(&sblock, blkno))
                        goto foundit;
        for (bp = bufhead.b_prev; bp != &bufhead; bp = bp->b_prev)
                if ((bp->b_flags & B_INUSE) == 0)
                        break;
        if (bp == &bufhead)
                errexit("deadlocked buffer pool\n");
        getblk(bp, blkno, size);
        diskreads++;
        /* fall through */
foundit:
        totalreads++;
        bp->b_prev->b_next = bp->b_next;
        bp->b_next->b_prev = bp->b_prev;
        bp->b_prev = &bufhead;
        bp->b_next = bufhead.b_next;
        bufhead.b_next->b_prev = bp;
        bufhead.b_next = bp;
        bp->b_flags |= B_INUSE;
        return (bp);
}

void
getblk(struct bufarea *bp, daddr32_t blk, long size)
{
        daddr32_t dblk;

        dblk = fsbtodb(&sblock, blk);
        if (bp->b_bno != dblk) {
                flush(fswritefd, bp);
                diskreads++;
                bp->b_errs = bread(fsreadfd, bp->b_un.b_buf, dblk, size);
                bp->b_bno = dblk;
                bp->b_size = size;
        }
}

void
flush(int fd, struct bufarea *bp)
{
        int i;

        if (!bp->b_dirty)
                return;
        if (bp->b_errs != 0)
                pfatal("WRITING %sZERO'ED BLOCK %d TO DISK\n",
                    (bp->b_errs == bp->b_size / DEV_BSIZE) ? "" : "PARTIALLY ",
                    bp->b_bno);
        bp->b_dirty = 0;
        bp->b_errs = 0;
        bwrite(fd, bp->b_un.b_buf, bp->b_bno, (long)bp->b_size);
        if (bp != &sblk)
                return;
        for (i = 0; i < sblock.e2fs_ngdb; i++) {
                bwrite(fswritefd, (char *)
                        &sblock.e2fs_gd[i* sblock.e2fs_bsize / sizeof(struct ext2_gd)],
                    fsbtodb(&sblock, ((sblock.e2fs_bsize>1024)?0:1)+i+1),
                    sblock.e2fs_bsize);
        }
}

static void
rwerror(char *mesg, daddr32_t blk)
{

        if (preen == 0)
                printf("\n");
        pfatal("CANNOT %s: BLK %d", mesg, blk);
        if (reply("CONTINUE") == 0)
                errexit("Program terminated\n");
}

void
ckfini(int markclean)
{
        struct bufarea *bp, *nbp;
        int cnt = 0;

        if (fswritefd < 0) {
                (void)close(fsreadfd);
                return;
        }
        flush(fswritefd, &sblk);
        if (havesb && sblk.b_bno != SBOFF / DEV_BSIZE &&
            !preen && reply("UPDATE STANDARD SUPERBLOCKS")) {
                sblk.b_bno = SBOFF / DEV_BSIZE;
                sbdirty();
                flush(fswritefd, &sblk);
                copyback_sb(&asblk);
                asblk.b_dirty = 1;
                flush(fswritefd, &asblk);
        }
        for (bp = bufhead.b_prev; bp && bp != &bufhead; bp = nbp) {
                cnt++;
                flush(fswritefd, bp);
                nbp = bp->b_prev;
                free(bp->b_un.b_buf);
                free((char *)bp);
        }
        if (bufhead.b_size != cnt)
                errexit("Panic: lost %d buffers\n", bufhead.b_size - cnt);
        pbp = pdirbp = NULL;
        if (markclean && (sblock.e2fs.e2fs_state & E2FS_ISCLEAN) == 0) {
                /*
                 * Mark the file system as clean, and sync the superblock.
                 */
                if (preen)
                        pwarn("MARKING FILE SYSTEM CLEAN\n");
                else if (!reply("MARK FILE SYSTEM CLEAN"))
                        markclean = 0;
                if (markclean) {
                        sblock.e2fs.e2fs_state = E2FS_ISCLEAN;
                        sbdirty();
                        flush(fswritefd, &sblk);
                }
        }
        if (debug)
                printf("cache missed %ld of %ld (%d%%)\n", diskreads,
                    totalreads, (int)(diskreads * 100 / totalreads));
        (void)close(fsreadfd);
        (void)close(fswritefd);
}

int
bread(int fd, char *buf, daddr32_t blk, long size)
{
        char *cp;
        int i, errs;
        off_t offset;

        offset = blk;
        offset *= DEV_BSIZE;
        if (pread(fd, buf, size, offset) == size)
                return (0);
        rwerror("READ", blk);
        errs = 0;
        memset(buf, 0, (size_t)size);
        printf("THE FOLLOWING DISK SECTORS COULD NOT BE READ:");
        for (cp = buf, i = 0; i < size; i += secsize, cp += secsize) {
                if (pread(fd, cp, secsize, offset + i) != secsize) {
                        if (secsize != DEV_BSIZE)
                                printf(" %lld (%lld),",
                                    (long long)(offset + i) / secsize,
                                    (long long)blk + i / DEV_BSIZE);
                        else
                                printf(" %lld,", (long long)blk +
                                    i / DEV_BSIZE);
                        errs++;
                }
        }
        printf("\n");
        return (errs);
}

void
bwrite(int fd, char *buf, daddr32_t blk, long size)
{
        int i;
        char *cp;
        off_t offset;

        if (fd < 0)
                return;
        offset = blk;
        offset *= DEV_BSIZE;
        if (pwrite(fd, buf, size, offset) == size) {
                fsmodified = 1;
                return;
        }
        rwerror("WRITE", blk);
        printf("THE FOLLOWING SECTORS COULD NOT BE WRITTEN:");
        for (cp = buf, i = 0; i < size; i += secsize, cp += secsize)
                if (pwrite(fd, cp, secsize, offset + i) != secsize) {
                        if (secsize != DEV_BSIZE)
                                printf(" %lld (%lld),",
                                    (long long)(offset + i) / secsize,
                                    (long long)blk + i / DEV_BSIZE);
                        else
                                printf(" %lld,", (long long)blk +
                                    i / DEV_BSIZE);
                }
        printf("\n");
        return;
}

/*
 * allocate a data block
 */
int
allocblk(void)
{
        int i;

        for (i = 0; i < maxfsblock - 1; i++) {
                if (testbmap(i))
                                continue;
                setbmap(i);
                n_blks ++;
                return (i);
        }
        return (0);
}

/*
 * Free a previously allocated block
 */
void
freeblk(daddr32_t blkno)
{
        struct inodesc idesc;

        idesc.id_blkno = blkno;
        idesc.id_numfrags = 1;
        (void)pass4check(&idesc);
}

/*
 * Find a pathname
 */
void
getpathname(char *namebuf, size_t buflen, ino_t curdir, ino_t ino)
{
        size_t len;
        char *cp;
        struct inodesc idesc;
        static int busy = 0;

        if (curdir == ino && ino == EXT2_ROOTINO) {
                (void)strlcpy(namebuf, "/", buflen);
                return;
        }
        if (busy ||
            (statemap[curdir] != DSTATE && statemap[curdir] != DFOUND)) {

                (void)strlcpy(namebuf, "?", buflen);
                return;
        }
        busy = 1;
        memset(&idesc, 0, sizeof(struct inodesc));
        idesc.id_type = DATA;
        idesc.id_fix = IGNORE;
        cp = &namebuf[buflen - 1];
        *cp = '\0';
        if (curdir != ino) {
                idesc.id_parent = curdir;
                goto namelookup;
        }
        while (ino != EXT2_ROOTINO) {
                idesc.id_number = ino;
                idesc.id_func = findino;
                idesc.id_name = "..";
                if ((ckinode(ginode(ino), &idesc) & FOUND) == 0)
                        break;
        namelookup:
                idesc.id_number = idesc.id_parent;
                idesc.id_parent = ino;
                idesc.id_func = findname;
                idesc.id_name = namebuf;
                if ((ckinode(ginode(idesc.id_number), &idesc)&FOUND) == 0)
                        break;
                len = strlen(namebuf);
                cp -= len;
                memmove(cp, namebuf, len);
                *(--cp) = '/';
                if (cp < &namebuf[EXT2FS_MAXNAMLEN])
                        break;
                ino = idesc.id_number;
        }
        busy = 0;
        if (ino != EXT2_ROOTINO)
                *(--cp) = '?';
        memmove(namebuf, cp, (size_t)(&namebuf[buflen] - cp));
}

void
catch(int signo)
{
        ckfini(0);                      /* XXX signal race */
        _exit(12);
}

/*
 * When preening, allow a single quit to signal
 * a special exit after filesystem checks complete
 * so that reboot sequence may be interrupted.
 */
void
catchquit(int signo)
{
        extern volatile sig_atomic_t returntosingle;
        static const char message[] =
            "returning to single-user after filesystem check\n";

        write(STDOUT_FILENO, message, sizeof(message)-1);
        returntosingle = 1;
        (void)signal(SIGQUIT, SIG_DFL);
}

/*
 * Ignore a single quit signal; wait and flush just in case.
 * Used by child processes in preen.
 */
void
voidquit(int signo)
{
        int save_errno = errno;

        sleep(1);
        (void)signal(SIGQUIT, SIG_IGN);
        (void)signal(SIGQUIT, SIG_DFL);
        errno = save_errno;
}

/*
 * determine whether an inode should be fixed.
 */
int
dofix(struct inodesc *idesc, char *msg)
{

        switch (idesc->id_fix) {

        case DONTKNOW:
                if (idesc->id_type == DATA)
                        direrror(idesc->id_number, msg);
                else
                        pwarn("%s", msg);
                if (preen) {
                        printf(" (SALVAGED)\n");
                        idesc->id_fix = FIX;
                        return (ALTERED);
                }
                if (reply("SALVAGE") == 0) {
                        idesc->id_fix = NOFIX;
                        return (0);
                }
                idesc->id_fix = FIX;
                return (ALTERED);

        case FIX:
                return (ALTERED);

        case NOFIX:
        case IGNORE:
                return (0);

        default:
                errexit("UNKNOWN INODESC FIX MODE %d\n", idesc->id_fix);
        }
        /* NOTREACHED */
}