/*      $NetBSD: inode.c,v 1.79 2025/02/25 15:29:00 andvar Exp $        */

/*
 * 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/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)inode.c     8.8 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: inode.c,v 1.79 2025/02/25 15:29:00 andvar Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/time.h>
#include <sys/stat.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>
#include <ufs/ufs/ufs_bswap.h>

#ifndef SMALL
#include <err.h>
#include <pwd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

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

static ino_t startinum;

static int iblock(struct inodesc *, long, u_int64_t);
#ifndef NO_FFS_EI
static void swap_dinode1(union dinode *, int);
static void swap_dinode2(union dinode *, int);
#endif

int
ckinode(union dinode *dp, struct inodesc *idesc)
{
        int ret, offset, i;
        union dinode dino;
        u_int64_t sizepb;
        int64_t remsize;
        daddr_t ndb;
        mode_t mode;
        char pathbuf[MAXPATHLEN + 1];

        if (idesc->id_fix != IGNORE)
                idesc->id_fix = DONTKNOW;
        idesc->id_entryno = 0;
        idesc->id_filesize = iswap64(DIP(dp, size));
        mode = iswap16(DIP(dp, mode)) & IFMT;
        if (mode == IFBLK || mode == IFCHR || (mode == IFLNK &&
            (idesc->id_filesize < sblock->fs_maxsymlinklen ||
            (isappleufs && (idesc->id_filesize < APPLEUFS_MAXSYMLINKLEN)) ||
             (sblock->fs_maxsymlinklen == 0 && DIP(dp, blocks) == 0))))
                return (KEEPON);
        if (is_ufs2)
                dino.dp2 = dp->dp2;
        else
                dino.dp1 = dp->dp1;
        ndb = howmany(iswap64(DIP(&dino, size)), sblock->fs_bsize);
        for (i = 0; i < UFS_NDADDR; i++) {
                if (--ndb == 0 &&
                    (offset = ffs_blkoff(sblock, iswap64(DIP(&dino, size)))) != 0)
                        idesc->id_numfrags =
                                ffs_numfrags(sblock, ffs_fragroundup(sblock, offset));
                else
                        idesc->id_numfrags = sblock->fs_frag;
                if (DIP(&dino, db[i]) == 0) {
                        if (idesc->id_type == DATA && ndb >= 0) {
                                /* An empty block in a directory XXX */
                                markclean = 0;
                                getpathname(pathbuf, sizeof(pathbuf),
                                    idesc->id_number, idesc->id_number);
                                pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
                                    pathbuf);
                                if (reply("ADJUST LENGTH") == 1) {
                                        dp = ginode(idesc->id_number);
                                        DIP_SET(dp, size, iswap64(i *
                                            sblock->fs_bsize));
                                        printf(
                                            "YOU MUST RERUN FSCK AFTERWARDS\n");
                                        rerun = 1;
                                        inodirty();
                                }
                        }
                        continue;
                }
                if (is_ufs2)
                        idesc->id_blkno = iswap64(dino.dp2.di_db[i]);
                else
                        idesc->id_blkno = iswap32(dino.dp1.di_db[i]);
                if (idesc->id_type != DATA)
                        ret = (*idesc->id_func)(idesc);
                else
                        ret = dirscan(idesc);
                if (ret & STOP)
                        return (ret);
        }
        idesc->id_numfrags = sblock->fs_frag;
        remsize = iswap64(DIP(&dino, size)) - sblock->fs_bsize * UFS_NDADDR;
        sizepb = sblock->fs_bsize;
        for (i = 0; i < UFS_NIADDR; i++) {
                if (DIP(&dino, ib[i])) {
                        if (is_ufs2)
                                idesc->id_blkno = iswap64(dino.dp2.di_ib[i]);
                        else
                                idesc->id_blkno = iswap32(dino.dp1.di_ib[i]);
                        ret = iblock(idesc, i + 1, remsize);
                        if (ret & STOP)
                                return (ret);
                } else {
                        if (idesc->id_type == DATA && remsize > 0) {
                                /* An empty block in a directory XXX */
                                markclean = 0;
                                getpathname(pathbuf, sizeof(pathbuf),
                                    idesc->id_number, idesc->id_number);
                                pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
                                    pathbuf);
                                if (reply("ADJUST LENGTH") == 1) {
                                        dp = ginode(idesc->id_number);
                                        DIP_SET(dp, size,
                                            iswap64(iswap64(DIP(dp, size))
                                                - remsize));
                                        remsize = 0;
                                        printf(
                                            "YOU MUST RERUN FSCK AFTERWARDS\n");
                                        rerun = 1;
                                        inodirty();
                                        break;
                                }
                        }
                }
                sizepb *= FFS_NINDIR(sblock);
                remsize -= sizepb;
        }
        return (KEEPON);
}

static int
iblock(struct inodesc *idesc, long ilevel, u_int64_t isize)
{
        struct bufarea *bp;
        int i, n, (*func) (struct inodesc *), nif;
        u_int64_t sizepb;
        char buf[BUFSIZ];
        char pathbuf[MAXPATHLEN + 1];
        union dinode *dp;

        if (idesc->id_type != DATA) {
                func = idesc->id_func;
                if (((n = (*func)(idesc)) & KEEPON) == 0)
                        return (n);
        } else
                func = dirscan;
        if (chkrange(idesc->id_blkno, idesc->id_numfrags))
                return (SKIP);
        bp = getdatablk(idesc->id_blkno, sblock->fs_bsize);
        ilevel--;
        for (sizepb = sblock->fs_bsize, i = 0; i < ilevel; i++)
                sizepb *= FFS_NINDIR(sblock);
        if (howmany(isize, sizepb) > (size_t)FFS_NINDIR(sblock))
                nif = FFS_NINDIR(sblock);
        else
                nif = howmany(isize, sizepb);
        if (do_blkswap) { /* swap byte order of the whole blk */
                if (is_ufs2) {
                        for (i = 0; i < nif; i++)
                                bp->b_un.b_indir2[i] =
                                    bswap64(bp->b_un.b_indir2[i]);
                } else {
                        for (i = 0; i < nif; i++)
                                bp->b_un.b_indir1[i] =
                                    bswap32(bp->b_un.b_indir1[i]);
                }
                dirty(bp);
                flush(fswritefd, bp);
        }
        if (idesc->id_func == pass1check && nif < FFS_NINDIR(sblock)) {
                for (i = nif; i < FFS_NINDIR(sblock); i++) {
                        if (IBLK(bp, i) == 0)
                                continue;
                        (void)snprintf(buf, sizeof(buf),
                            "PARTIALLY TRUNCATED INODE I=%llu",
                            (unsigned long long)idesc->id_number);
                        if (dofix(idesc, buf)) {
                                IBLK_SET(bp, i, 0);
                                dirty(bp);
                        } else
                                markclean = 0;
                }
                flush(fswritefd, bp);
        }
        for (i = 0; i < nif; i++) {
                if (IBLK(bp, i)) {
                        if (is_ufs2)
                                idesc->id_blkno = iswap64(bp->b_un.b_indir2[i]);
                        else
                                idesc->id_blkno = iswap32(bp->b_un.b_indir1[i]);
                        if (ilevel == 0)
                                n = (*func)(idesc);
                        else
                                n = iblock(idesc, ilevel, isize);
                        if (n & STOP) {
                                bp->b_flags &= ~B_INUSE;
                                return (n);
                        }
                } else {
                        if (idesc->id_type == DATA && isize > 0) {
                                /* An empty block in a directory XXX */
                                markclean = 0;
                                getpathname(pathbuf, sizeof(pathbuf),
                                    idesc->id_number, idesc->id_number);
                                pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
                                    pathbuf);
                                if (reply("ADJUST LENGTH") == 1) {
                                        dp = ginode(idesc->id_number);
                                        DIP_SET(dp, size,
                                            iswap64(iswap64(DIP(dp, size))
                                                - isize));
                                        isize = 0;
                                        printf(
                                            "YOU MUST RERUN FSCK AFTERWARDS\n");
                                        rerun = 1;
                                        inodirty();
                                        bp->b_flags &= ~B_INUSE;
                                        return(STOP);
                                }
                        }
                }
                isize -= sizepb;
        }
        bp->b_flags &= ~B_INUSE;
        return (KEEPON);
}

/*
 * Check that a block in a legal block number.
 * Return 0 if in range, 1 if out of range.
 */
int
chkrange(daddr_t blk, int cnt)
{
        int c;

        if (cnt <= 0 || blk <= 0 || blk > maxfsblock ||
            cnt - 1 > maxfsblock - blk)
                return (1);
        if (cnt > sblock->fs_frag ||
            ffs_fragnum(sblock, blk) + cnt > sblock->fs_frag) {
                if (debug)
                        printf("bad size: blk %lld, offset %d, size %d\n",
                            (long long)blk, (int)ffs_fragnum(sblock, blk), cnt);
        }
        c = dtog(sblock, blk);
        if (blk < cgdmin(sblock, c)) {
                if ((blk + cnt) > cgsblock(sblock, c)) {
                        if (debug) {
                                printf("blk %lld < cgdmin %lld;",
                                    (long long)blk,
                                    (long long)cgdmin(sblock, c));
                                printf(" blk + cnt %lld > cgsbase %lld\n",
                                    (long long)(blk + cnt),
                                    (long long)cgsblock(sblock, c));
                        }
                        return (1);
                }
        } else {
                if ((blk + cnt) > cgbase(sblock, c+1)) {
                        if (debug)  {
                                printf("blk %lld >= cgdmin %lld;",
                                    (long long)blk,
                                    (long long)cgdmin(sblock, c));
                                printf(" blk + cnt %lld > sblock->fs_fpg %d\n",
                                    (long long)(blk+cnt), sblock->fs_fpg);
                        }
                        return (1);
                }
        }
        return (0);
}

/*
 * General purpose interface for reading inodes.
 */
union dinode *
ginode(ino_t inumber)
{
        daddr_t iblk;
        int blkoff;

        if (inumber < UFS_ROOTINO || inumber > maxino)
                errexit("bad inode number %llu to ginode",
                    (unsigned long long)inumber);
        if (startinum == 0 ||
            inumber < startinum || inumber >= startinum + FFS_INOPB(sblock)) {
                iblk = ino_to_fsba(sblock, inumber);
                if (pbp != 0)
                        pbp->b_flags &= ~B_INUSE;
                pbp = getdatablk(iblk, sblock->fs_bsize);
                startinum = (inumber / FFS_INOPB(sblock)) * FFS_INOPB(sblock);
        }
        if (is_ufs2) {
                blkoff = (inumber % FFS_INOPB(sblock)) * DINODE2_SIZE;
                return ((union dinode *)((caddr_t)pbp->b_un.b_buf + blkoff));
        }
        blkoff = (inumber % FFS_INOPB(sblock)) * DINODE1_SIZE;
        return ((union dinode *)((caddr_t)pbp->b_un.b_buf + blkoff));
}

#ifndef NO_FFS_EI
static void
swap_dinode1(union dinode *dp, int n)
{
        int i, j;
        struct ufs1_dinode *dp1;
        int32_t maxsymlinklen = sblock->fs_maxsymlinklen;
        if (isappleufs)
                maxsymlinklen = APPLEUFS_MAXSYMLINKLEN;

        dp1 = (struct ufs1_dinode *)&dp->dp1;
        for (i = 0; i < n; i++, dp1++) {
                ffs_dinode1_swap(dp1, dp1);
                if (((iswap16(dp1->di_mode) & IFMT) != IFLNK) ||
                    doinglevel2 ||
                    (maxsymlinklen < 0) ||
                    (iswap64(dp1->di_size) > (uint64_t)maxsymlinklen)) {
                        for (j = 0; j < UFS_NDADDR; j++)
                            dp1->di_db[j] = bswap32(dp1->di_db[j]);
                        for (j = 0; j < UFS_NIADDR; j++)
                            dp1->di_ib[j] = bswap32(dp1->di_ib[j]);
                }
        }
}

static void
swap_dinode2(union dinode *dp, int n)
{
        int i, j;
        struct ufs2_dinode *dp2;

        dp2 = (struct ufs2_dinode *)&dp->dp2;
        for (i = 0; i < n; i++, dp2++) {
                ffs_dinode2_swap(dp2, dp2);
                if ((iswap16(dp2->di_mode) & IFMT) != IFLNK) {
                        for (j = 0; j < UFS_NXADDR; j++)
                                dp2->di_extb[j] = bswap64(dp2->di_extb[j]);
                        for (j = 0; j < UFS_NDADDR; j++)
                                dp2->di_db[j] = bswap64(dp2->di_db[j]);
                        for (j = 0; j < UFS_NIADDR; j++)
                                dp2->di_ib[j] = bswap64(dp2->di_ib[j]);
                }
        }
}
#endif /* !NO_FFS_EI */

/*
 * Special purpose version of ginode used to optimize first pass
 * over all the inodes in numerical order.
 */
ino_t nextino, lastinum, lastvalidinum;
long readcnt, readpercg, fullcnt, inobufsize, partialcnt, partialsize;
union dinode *inodebuf;

union dinode *
getnextinode(ino_t inumber)
{
        long size;
        daddr_t dblk;
        static union dinode *dp;
        union dinode *ret;

        if (inumber != nextino++ || inumber > lastvalidinum)
                errexit("bad inode number %llu to nextinode",
                    (unsigned long long)inumber);

        if (inumber >= lastinum) {
                readcnt++;
                dblk = FFS_FSBTODB(sblock, ino_to_fsba(sblock, lastinum));
                if (readcnt % readpercg == 0) {
                        size = partialsize;
                        lastinum += partialcnt;
                } else {
                        size = inobufsize;
                        lastinum += fullcnt;
                }
                (void)bread(fsreadfd, (caddr_t)inodebuf, dblk, size);
                if (doswap) {
                        if (is_ufs2)
                                swap_dinode2(inodebuf, lastinum - inumber);
                        else
                                swap_dinode1(inodebuf, lastinum - inumber);
                        bwrite(fswritefd, (char *)inodebuf, dblk, size);
                }
                dp = (union dinode *)inodebuf;
        }
        ret = dp;
        dp = (union dinode *)
            ((char *)dp + (is_ufs2 ? DINODE2_SIZE : DINODE1_SIZE));
        return ret;
}

void
setinodebuf(ino_t inum)
{

        if (inum % sblock->fs_ipg != 0)
                errexit("bad inode number %llu to setinodebuf",
                    (unsigned long long)inum);

        lastvalidinum = inum + sblock->fs_ipg - 1;
        startinum = 0;
        nextino = inum;
        lastinum = inum;
        readcnt = 0;
        if (inodebuf != NULL)
                return;
        inobufsize = ffs_blkroundup(sblock, INOBUFSIZE);
        fullcnt = inobufsize / (is_ufs2 ? DINODE2_SIZE : DINODE1_SIZE);
        readpercg = sblock->fs_ipg / fullcnt;
        partialcnt = sblock->fs_ipg % fullcnt;
        partialsize = partialcnt * (is_ufs2 ? DINODE2_SIZE : DINODE1_SIZE);
        if (partialcnt != 0) {
                readpercg++;
        } else {
                partialcnt = fullcnt;
                partialsize = inobufsize;
        }
        if (inodebuf == NULL &&
            (inodebuf = aligned_alloc(DEV_BSIZE, (unsigned)inobufsize)) == NULL)
                errexit("Cannot allocate space for inode buffer");
}

void
freeinodebuf(void)
{

        if (inodebuf != NULL)
                free((char *)inodebuf);
        inodebuf = NULL;
}

/*
 * Routines to maintain information about directory inodes.
 * This is built during the first pass and used during the
 * second and third passes.
 *
 * Enter inodes into the cache.
 */
void
cacheino(union dinode *dp, ino_t inumber)
{
        struct inoinfo *inp;
        struct inoinfo **inpp, **ninpsort;
        unsigned int i, blks, extra;
        int64_t size;

        size = iswap64(DIP(dp, size));
        blks = howmany(size, sblock->fs_bsize);
        if (blks > UFS_NDADDR)
                blks = UFS_NDADDR + UFS_NIADDR;
        if (blks > 0)
                extra = (blks - 1) * sizeof (int64_t);
        else
                extra = 0;
        inp = malloc(sizeof(*inp) + extra);
        if (inp == NULL)
                return;
        inpp = &inphead[inumber % dirhash];
        inp->i_nexthash = *inpp;
        *inpp = inp;
        inp->i_child = inp->i_sibling = 0;
        if (inumber == UFS_ROOTINO)
                inp->i_parent = UFS_ROOTINO;
        else
                inp->i_parent = (ino_t)0;
        inp->i_dotdot = (ino_t)0;
        inp->i_number = inumber;
        inp->i_isize = size;
        inp->i_numblks = blks;
        for (i = 0; i < (blks < UFS_NDADDR ? blks : UFS_NDADDR); i++)
                inp->i_blks[i] = DIP(dp, db[i]);
        if (blks > UFS_NDADDR)
                for (i = 0; i < UFS_NIADDR; i++)
                        inp->i_blks[UFS_NDADDR + i] = DIP(dp, ib[i]);
        if (inplast == listmax) {
                ninpsort = (struct inoinfo **)realloc((char *)inpsort,
                    (unsigned)(listmax + 100) * sizeof(struct inoinfo *));
                if (inpsort == NULL)
                        errexit("cannot increase directory list");
                inpsort = ninpsort;
                listmax += 100;
        }
        inpsort[inplast++] = inp;
}

/*
 * Look up an inode cache structure.
 */
struct inoinfo *
getinoinfo(ino_t inumber)
{
        struct inoinfo *inp;

        for (inp = inphead[inumber % dirhash]; inp; inp = inp->i_nexthash) {
                if (inp->i_number != inumber)
                        continue;
                return (inp);
        }
        errexit("cannot find inode %llu", (unsigned long long)inumber);
        return ((struct inoinfo *)0);
}

/*
 * Clean up all the inode cache structure.
 */
void
inocleanup(void)
{
        struct inoinfo **inpp;

        if (inphead == NULL)
                return;
        for (inpp = &inpsort[inplast - 1]; inpp >= inpsort; inpp--)
                free((char *)(*inpp));
        free((char *)inphead);
        free((char *)inpsort);
        inphead = inpsort = NULL;
}

void
inodirty(void)
{

        dirty(pbp);
}

void
clri(struct inodesc *idesc, const char *type, int flag)
{
        union dinode *dp;

        dp = ginode(idesc->id_number);
        if (flag == 1) {
                pwarn("%s %s", type,
                    (iswap16(DIP(dp, mode)) & IFMT) == IFDIR ? "DIR" : "FILE");
                pinode(idesc->id_number);
        }
        if (preen || reply("CLEAR") == 1) {
                if (preen)
                        printf(" (CLEARED)\n");
                n_files--;
                /*
                 * ckinode will call id_func (actually always pass4check)
                 * which will update the block count
                 */
                if (idesc->id_type != SNAP)
                        update_uquot(idesc->id_number,
                            idesc->id_uid, idesc->id_gid, 0, -1);
                (void)ckinode(dp, idesc);
                clearinode(dp);
                inoinfo(idesc->id_number)->ino_state = USTATE;
                inodirty();
        } else
                markclean = 0;
}

int
findname(struct inodesc *idesc)
{
        struct direct *dirp = idesc->id_dirp;
        size_t len;
        char *buf;

        if (iswap32(dirp->d_ino) != idesc->id_parent || idesc->id_entryno < 2) {
                idesc->id_entryno++;
                return (KEEPON);
        }
        if ((len = dirp->d_namlen + 1) > MAXPATHLEN) {
                /* XXX: We don't fix but we ignore */
                len = MAXPATHLEN;
        }
        /* this is namebuf from utilities.c */
        buf = __UNCONST(idesc->id_name);
        (void)memcpy(buf, dirp->d_name, (size_t)dirp->d_namlen + 1);
        return (STOP|FOUND);
}

int
findino(struct inodesc *idesc)
{
        struct direct *dirp = idesc->id_dirp;

        if (dirp->d_ino == 0)
                return (KEEPON);
        if (strcmp(dirp->d_name, idesc->id_name) == 0 &&
            iswap32(dirp->d_ino) >= UFS_ROOTINO && iswap32(dirp->d_ino) <= maxino) {
                idesc->id_parent = iswap32(dirp->d_ino);
                return (STOP|FOUND);
        }
        return (KEEPON);
}

int
clearentry(struct inodesc *idesc)
{
        struct direct *dirp = idesc->id_dirp;

        if (dirp->d_ino != idesc->id_parent || idesc->id_entryno < 2) {
                idesc->id_entryno++;
                return (KEEPON);
        }
        dirp->d_ino = 0;
        return (STOP|FOUND|ALTERED);
}

void
pinode(ino_t ino)
{
        union dinode *dp;
        struct passwd *pw;

        printf(" I=%llu ", (unsigned long long)ino);
        if (ino < UFS_ROOTINO || ino > maxino)
                return;
        dp = ginode(ino);
        printf(" OWNER=");
#ifndef SMALL
        if (Uflag && (pw = getpwuid((int)iswap32(DIP(dp, uid)))) != 0)
                printf("%s ", pw->pw_name);
        else
#endif
                printf("%u ", (unsigned)iswap32(DIP(dp, uid)));
        printf("MODE=%o\n", iswap16(DIP(dp, mode)));
        if (preen)
                printf("%s: ", cdevname());
        printf("SIZE=%llu ", (unsigned long long)iswap64(DIP(dp, size)));
        printf("MTIME=%s ", print_mtime(iswap32(DIP(dp, mtime))));
}

void
blkerror(ino_t ino, const char *type, daddr_t blk)
{
        struct inostat *info;

        pfatal("%lld %s I=%llu", (long long)blk, type, (unsigned long long)ino);
        printf("\n");
        info = inoinfo(ino);
        switch (info->ino_state) {

        case FSTATE:
                info->ino_state = FCLEAR;
                return;

        case DSTATE:
                info->ino_state = DCLEAR;
                return;

        case FCLEAR:
        case DCLEAR:
                return;

        default:
                errexit("BAD STATE %d TO BLKERR", info->ino_state);
                /* NOTREACHED */
        }
}

/*
 * allocate an unused inode
 */
ino_t
allocino(ino_t request, int type)
{
        ino_t ino;
        union dinode *dp;
        struct ufs1_dinode *dp1;
        struct ufs2_dinode *dp2;
        time_t t;
        struct cg *cgp = cgrp;
        int cg;
        struct inostat *info = NULL;
        int nfrags;

        if (request == 0)
                request = UFS_ROOTINO;
        else if (inoinfo(request)->ino_state != USTATE)
                return (0);
        for (ino = request; ino < maxino; ino++) {
                info = inoinfo(ino);
                if (info->ino_state == USTATE)
                        break;
        }
        if (ino == maxino)
                return (0);
        cg = ino_to_cg(sblock, ino);
        /* If necessary, extend the inoinfo array. grow exponentially */
        if ((ino % sblock->fs_ipg) >= inostathead[cg].il_numalloced) {
                size_t newalloced, i;
                newalloced = MIN(sblock->fs_ipg,
                        MAX(2 * inostathead[cg].il_numalloced, 10));
                info = calloc(newalloced, sizeof(*info));
                if (info == NULL) {
                        pwarn("cannot alloc %zu bytes to extend inoinfo\n",
                                sizeof(struct inostat) * newalloced);
                        return 0;
                }
                memmove(info, inostathead[cg].il_stat,
                        inostathead[cg].il_numalloced * sizeof(*info));
                for (i = inostathead[cg].il_numalloced; i < newalloced; i++) {
                        info[i].ino_state = USTATE;
                }
                if (inostathead[cg].il_numalloced)
                        free(inostathead[cg].il_stat);
                inostathead[cg].il_stat = info;
                inostathead[cg].il_numalloced = newalloced;
                info = inoinfo(ino);
        }
        getblk(&cgblk, cgtod(sblock, cg), sblock->fs_cgsize);
        memcpy(cgp, cgblk.b_un.b_cg, sblock->fs_cgsize);
        if ((doswap && !needswap) || (!doswap && needswap))
                ffs_cg_swap(cgblk.b_un.b_cg, cgp, sblock);
        if (!cg_chkmagic(cgp, 0))
                pfatal("CG %d: ALLOCINO: BAD MAGIC NUMBER\n", cg);
        if (doswap)
                cgdirty();
        setbit(cg_inosused(cgp, 0), ino % sblock->fs_ipg);
        cgp->cg_cs.cs_nifree--;
        sblock->fs_cstotal.cs_nifree--;
        sblock->fs_cs(fs, cg).cs_nifree--;
        sbdirty();
        switch (type & IFMT) {
        case IFDIR:
                info->ino_state = DSTATE;
                cgp->cg_cs.cs_ndir++;
                nfrags = 1;
                break;
        case IFREG:
                info->ino_state = FSTATE;
                nfrags = sblock->fs_frag;
                break;
        case IFLNK:
                info->ino_state = FSTATE;
                nfrags = 1;
                break;
        default:
                return (0);
        }
        cgdirty();
        dp = ginode(ino);
        if (is_ufs2) {
                dp2 = &dp->dp2;
                dp2->di_db[0] = iswap64(allocblk(nfrags));
                if (dp2->di_db[0] == 0) {
                        info->ino_state = USTATE;
                        return (0);
                }
                dp2->di_mode = iswap16(type);
                dp2->di_flags = 0;
                (void)time(&t);
                dp2->di_atime = iswap64(t);
                dp2->di_mtime = dp2->di_ctime = dp2->di_atime;
                dp2->di_size = iswap64(ffs_lfragtosize(sblock, nfrags));
                dp2->di_blocks = iswap64(btodb(ffs_lfragtosize(sblock, nfrags)));
        } else {
                dp1 = &dp->dp1;
                dp1->di_db[0] = iswap32(allocblk(nfrags));
                if (dp1->di_db[0] == 0) {
                        info->ino_state = USTATE;
                        return (0);
                }
                dp1->di_mode = iswap16(type);
                dp1->di_flags = 0;
                (void)time(&t);
                dp1->di_atime = iswap32(t);
                dp1->di_mtime = dp1->di_ctime = dp1->di_atime;
                dp1->di_size = iswap64(ffs_lfragtosize(sblock, nfrags));
                dp1->di_blocks = iswap32(btodb(ffs_lfragtosize(sblock, nfrags)));
        }
        n_files++;
        inodirty();
        if (newinofmt)
                info->ino_type = IFTODT(type);
        return (ino);
}

/*
 * deallocate an inode
 */
void
freeino(ino_t ino)
{
        struct inodesc idesc;
        union dinode *dp;
        struct cg *cgp = cgrp;
        int cg;

        cg = ino_to_cg(sblock, ino);
        getblk(&cgblk, cgtod(sblock, cg), sblock->fs_cgsize);
        memcpy(cgp, cgblk.b_un.b_cg, sblock->fs_cgsize);
        if ((doswap && !needswap) || (!doswap && needswap))
                ffs_cg_swap(cgblk.b_un.b_cg, cgp, sblock);
        if (!cg_chkmagic(cgp, 0)) {
                pwarn("CG %d: FREEINO: BAD MAGIC NUMBER\n", cg);
                cgp = NULL;
        }

        memset(&idesc, 0, sizeof(struct inodesc));
        idesc.id_func = pass4check;
        idesc.id_number = ino;
        dp = ginode(ino);
        idesc.id_uid = iswap32(DIP(dp, uid));
        idesc.id_gid = iswap32(DIP(dp, gid));
        if (iswap32(DIP(dp, flags)) & SF_SNAPSHOT)
                idesc.id_type = SNAP;
        else
                idesc.id_type = ADDR;
        (void)ckinode(dp, &idesc);
        clearinode(dp);
        inodirty();
        inoinfo(ino)->ino_state = USTATE;
        if (idesc.id_type != SNAP)
                update_uquot(idesc.id_number,
                    idesc.id_uid, idesc.id_gid, 0, -1);
        n_files--;
        if (cgp) {
                clrbit(cg_inosused(cgp, 0), ino % sblock->fs_ipg);
                cgp->cg_cs.cs_nifree++;
                sblock->fs_cstotal.cs_nifree++;
                sblock->fs_cs(fs, cg).cs_nifree++;
                sbdirty();
                cgdirty();
        }
}

/* read a data block from inode */
ssize_t
readblk(union dinode *dp, off_t offset, struct bufarea **bp)
{
        daddr_t blkno = ffs_lblkno(sblock, offset);
        daddr_t iblkno;
        int type = IFMT & iswap16(DIP(dp, mode));
        ssize_t filesize = iswap64(DIP(dp, size));
        int ilevel;
        daddr_t nblks;
        const daddr_t naddrperblk = sblock->fs_bsize /
            (is_ufs2 ? sizeof(uint64_t) : sizeof(uint32_t));
        struct bufarea *ibp;

        *bp = NULL;
        offset &= ~(sblock->fs_bsize - 1);

        if (type != IFREG)
                return 0;
        if (offset >= filesize)
                return 0; /* short read */
        if (blkno < UFS_NDADDR) {
                blkno = is_ufs2 ? iswap64(dp->dp2.di_db[blkno]) :
                    iswap32(dp->dp1.di_db[blkno]);
                if (blkno == 0)
                        return 0;
                *bp = getdatablk(blkno, sblock->fs_bsize);
                return (bp != NULL) ? sblock->fs_bsize : 0;
        }
        blkno -= UFS_NDADDR;
        /* find indir level */
        for (ilevel = 1, nblks = naddrperblk;
             ilevel <= UFS_NIADDR;
             ilevel++, nblks *= naddrperblk) {
                if (blkno < nblks)
                        break;
                else
                        blkno -= nblks;
        }
        if (ilevel > UFS_NIADDR)
                errexit("bad offset %" PRIu64 " to readblk", offset);

        /* get the first indirect block */
        iblkno = is_ufs2 ? iswap64(dp->dp2.di_ib[ilevel - 1]) :
                    iswap32(dp->dp1.di_ib[ilevel - 1]);
        if (iblkno == 0)
                return 0;
        ibp = getdatablk(iblkno, sblock->fs_bsize);
        /* walk indirect blocks up to the data block */
        for (; ilevel >0 ; ilevel--) {
                nblks = nblks / naddrperblk;
                if (is_ufs2)
                        iblkno = iswap64(ibp->b_un.b_indir2[blkno / nblks]);
                else
                        iblkno = iswap32(ibp->b_un.b_indir1[blkno / nblks]);
                if (iblkno == 0)
                        return 0;
                blkno = blkno % nblks;
                ibp->b_flags &= ~B_INUSE;
                ibp = getdatablk(iblkno, sblock->fs_bsize);
        }
        *bp = ibp;
        return sblock->fs_bsize;
}

static struct bufarea * getnewblk(daddr_t *);
static struct bufarea *
getnewblk(daddr_t *blkno)
{
        struct bufarea *bp;
        *blkno = allocblk(sblock->fs_frag);
        if (*blkno == 0)
                return NULL;
        bp = getdatablk(*blkno, sblock->fs_bsize);
        memset(bp->b_un.b_buf, 0, sblock->fs_bsize);
        return bp;
}

/* expand given inode by one full fs block */
struct bufarea *
expandfile(union dinode *dp)
{
        uint64_t filesize = iswap64(DIP(dp, size));
        daddr_t newblk, blkno, iblkno, nblks;
        daddr_t di_blocks;
        int ilevel;
        const daddr_t naddrperblk = sblock->fs_bsize /
            (is_ufs2 ? sizeof(uint64_t) : sizeof(uint32_t));
        struct bufarea *ibp, *bp = NULL;

        di_blocks = is_ufs2 ? iswap64(dp->dp2.di_blocks) :
            iswap32(dp->dp1.di_blocks);
        /* compute location of new block */
        blkno = ffs_lblkno(sblock, filesize);

        if (blkno < UFS_NDADDR) {
                /* easy way: allocate a direct block */
                if ((bp = getnewblk(&newblk)) == NULL) {
                        return NULL;
                }
                di_blocks += btodb(sblock->fs_bsize);

                if (is_ufs2) {
                        dp->dp2.di_db[blkno] = iswap64(newblk);
                } else {
                        dp->dp1.di_db[blkno] = iswap32(newblk);
                }
                goto out;
        }
        blkno -= UFS_NDADDR;
        /* find indir level */
        for (ilevel = 1, nblks = naddrperblk;
             ilevel <= UFS_NIADDR;
             ilevel++, nblks *= naddrperblk) {
                if (blkno < nblks)
                        break;
                else
                        blkno -= nblks;
        }
        if (ilevel > UFS_NIADDR)
                errexit("bad filesize %" PRIu64 " to expandfile", filesize);

        /* get the first indirect block, allocating if needed */
        if ((is_ufs2 ? iswap64(dp->dp2.di_ib[ilevel - 1]) :
                iswap32(dp->dp1.di_ib[ilevel - 1])) == 0) {
                if ((ibp = getnewblk(&newblk)) == NULL)
                        return 0;
                di_blocks += btodb(sblock->fs_bsize);
                if (is_ufs2)
                        dp->dp2.di_ib[ilevel - 1] = iswap64(newblk);
                else
                        dp->dp1.di_ib[ilevel - 1] = iswap32(newblk);
        } else {
                ibp = getdatablk(is_ufs2 ? iswap64(dp->dp2.di_ib[ilevel - 1]) :
                    iswap32(dp->dp1.di_ib[ilevel - 1]), sblock->fs_bsize);
        }
        /* walk indirect blocks up to the data block */
        for (; ilevel >0 ; ilevel--) {
                nblks = nblks / naddrperblk;
                if (is_ufs2)
                        iblkno = iswap64(ibp->b_un.b_indir2[blkno / nblks]);
                else
                        iblkno = iswap32(ibp->b_un.b_indir1[blkno / nblks]);
                if (iblkno == 0) {
                        if ((bp = getnewblk(&newblk)) == NULL)
                                return NULL;
                        di_blocks += btodb(sblock->fs_bsize);
                        if (is_ufs2)
                                ibp->b_un.b_indir2[blkno / nblks] =
                                    iswap64(newblk);
                        else
                                ibp->b_un.b_indir1[blkno / nblks] =
                                    iswap32(newblk);
                        dirty(ibp);
                        ibp->b_flags &= ~B_INUSE;
                        ibp = bp;
                } else {
                        ibp->b_flags &= ~B_INUSE;
                        ibp = getdatablk(iblkno, sblock->fs_bsize);
                        bp = NULL;
                }
                blkno = blkno % nblks;
        }
        if (bp == NULL) {
                errexit("INTERNAL ERROR: "
                    "expandfile() failed to allocate a new block\n");
        }

out:
        filesize += sblock->fs_bsize;
        if (is_ufs2) {
                dp->dp2.di_size = iswap64(filesize);
                dp->dp2.di_blocks = iswap64(di_blocks);
        } else {
                dp->dp1.di_size = iswap64(filesize);
                dp->dp1.di_blocks = iswap32(di_blocks);
        }
        inodirty();
        return bp;
}