/*      $NetBSD: quotacheck.c,v 1.51 2023/01/07 19:41:30 chs Exp $      */

/*
 * Copyright (c) 1980, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Robert Elz at The University of Melbourne.
 *
 * 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
__COPYRIGHT("@(#) Copyright (c) 1980, 1990, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)quotacheck.c        8.6 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: quotacheck.c,v 1.51 2023/01/07 19:41:30 chs Exp $");
#endif
#endif /* not lint */

/*
 * Fix up / report on disk quotas & usage
 */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/queue.h>
#include <sys/statvfs.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/quota1.h>
#include <ufs/ufs/ufs_bswap.h>
#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>

#include <err.h>
#include <fcntl.h>
#include <fstab.h>
#include <pwd.h>
#include <grp.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <util.h>

#include "fsutil.h"
#include "quotautil.h"

#ifndef FS_UFS1_MAGIC
# define FS_UFS1_MAGIC          FS_MAGIC /* 0x011954 */
# define FS_UFS1_MAGIC_SWAPPED  0x54190100 /* bswap32(0x011954) */
# define DINODE1_SIZE           sizeof(struct dinode)
# define DINODE2_SIZE           0
#else
# define HAVE_UFSv2     1
#endif

#ifndef SBLOCKSIZE
# define SBLOCKSIZE     SBSIZE
#endif
#ifndef SBLOCKSEARCH
# define SBLOCKSEARCH   { SBSIZE, -1 }
#endif

static const char *quotagroup = QUOTAGROUP;

static union {
        struct  fs      sblk;
        char    dummy[MAXBSIZE];
} un;
#define sblock  un.sblk
static long dev_bsize;
static long maxino;

struct quotaname {
        long    flags;
        char    grpqfname[MAXPATHLEN + 1];
        char    usrqfname[MAXPATHLEN + 1];
};
#define HASUSR  1
#define HASGRP  2

struct fileusage {
        struct  fileusage *fu_next;
        u_long  fu_curinodes;
        u_long  fu_curblocks;
        uint32_t fu_id;         /* uid_t, gid_t */
        char    fu_name[1];
        /* actually bigger */
};
#define FUHASH 1024     /* must be power of two */
static struct fileusage *fuhead[MAXQUOTAS][FUHASH];


union comb_dinode {
#ifdef HAVE_UFSv2
        struct ufs1_dinode dp1;
        struct ufs2_dinode dp2;
#else
        struct dinode dp1;
#endif
};
#ifdef HAVE_UFSv2
#define DIP(dp, field) \
        (is_ufs2 ? (dp)->dp2.di_##field : (dp)->dp1.di_##field)
#else
#define DIP(dp, field) (dp)->dp1.di_##field
#endif


static int      aflag;          /* all file systems */
static int      gflag;          /* check group quotas */
static int      uflag;          /* check user quotas */
static int      vflag;          /* verbose */
static int      qflag;          /* quick but untidy mode */
static int      fi;             /* open disk file descriptor */
static uint32_t highid[MAXQUOTAS];/* highest addid()'ed identifier per type */
static int needswap;    /* FS is in swapped order */
static int got_siginfo = 0; /* got a siginfo signal */
static int is_ufs2;


static void usage(void) __attribute__((__noreturn__));
static void *needchk(struct fstab *);
static int chkquota(const char *, const char *, const char *, void *, pid_t *);
static int update(const char *, const char *, int);
static uint32_t skipforward(uint32_t, uint32_t, FILE *);
static int getquotagid(void);
static struct fileusage *lookup(uint32_t, int);
static struct fileusage *addid(uint32_t, int, const char *);
static uint32_t subsequent(uint32_t, int) ;
static union comb_dinode *getnextinode(ino_t);
static void setinodebuf(ino_t);
static void freeinodebuf(void);
static void bread(daddr_t, char *, long);
static void infohandler(int sig);
static void swap_dinode1(union comb_dinode *, int);
#ifdef HAVE_UFSv2
static void swap_dinode2(union comb_dinode *, int);
#endif

int
main(int argc, char *argv[])
{
        struct fstab *fs;
        struct passwd *pw;
        struct group *gr;
        struct quotaname *auxdata;
        int i, argnum, maxrun, errs;
        long done = 0;
        int flags = CHECK_PREEN;
        const char *name;
        int ch;

        errs = maxrun = 0;
        while ((ch = getopt(argc, argv, "aguvqdl:")) != -1) {
                switch(ch) {
                case 'a':
                        aflag++;
                        break;
                case 'd':
                        flags |= CHECK_DEBUG;
                        break;
                case 'g':
                        gflag++;
                        break;
                case 'u':
                        uflag++;
                        break;
                case 'q':
                        qflag++;
                        break;
                case 'v':
                        vflag++;
                        break;
                case 'l':
                        maxrun = atoi(optarg);
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if ((argc == 0 && !aflag) || (argc > 0 && aflag) || (!aflag && maxrun))
                usage();
        if (!gflag && !uflag) {
                gflag++;
                uflag++;
        }

        /* If -a, we do not want to pay the cost of processing every
         * group and password entry if there are no filesystems with quotas
         */
        if (aflag) {
                i = 0;
                while ((fs = getfsent()) != NULL) {
                        if (needchk(fs))
                                i = 1;
                }
                endfsent();
                if (!i) /* No filesystems with quotas */
                        return 0;
        }

        if (gflag) {
                setgrent();
                while ((gr = getgrent()) != 0)
                        (void) addid((uint32_t)gr->gr_gid, GRPQUOTA, gr->gr_name);
                endgrent();
        }
        if (uflag) {
                setpwent();
                while ((pw = getpwent()) != 0)
                        (void) addid((uint32_t)pw->pw_uid, USRQUOTA, pw->pw_name);
                endpwent();
        }
        if (aflag)
                exit(checkfstab(flags, maxrun, needchk, chkquota));
        if (setfsent() == 0)
                err(1, "%s: can't open", FSTAB);
        while ((fs = getfsent()) != NULL) {
                const char *fsspec;
                char buf[MAXPATHLEN];
                fsspec = getfsspecname(buf, sizeof(buf), fs->fs_spec);
                if (fsspec == NULL) {
                        warn("%s", buf);
                        continue;
                }
                if (((argnum = oneof(fs->fs_file, argv, argc)) >= 0 ||
                    (argnum = oneof(fsspec, argv, argc)) >= 0) &&
                    (auxdata = needchk(fs)) &&
                    (name = blockcheck(fsspec))) {
                        done |= 1 << argnum;
                        errs += chkquota(fs->fs_type, name, fs->fs_file,
                            auxdata, NULL);
                }
        }
        endfsent();
        for (i = 0; i < argc; i++)
                if ((done & (1 << i)) == 0)
                        warnx("%s not found in %s", argv[i], FSTAB);
        return errs;
}

static void
usage(void)
{
        const char *p = getprogname();
        (void)fprintf(stderr, "Usage: %s -a [-gquv] [-l <maxparallel>]\n"
            "\t%s [-gquv] <filesys> ...\n", p, p);
        exit(1);
}

static void *
needchk(struct fstab *fs)
{
        struct quotaname *qnp;
        char qfnp[MAXPATHLEN];

        if (strcmp(fs->fs_vfstype, "ffs") ||
            strcmp(fs->fs_type, FSTAB_RW))
                return (NULL);
        if ((qnp = malloc(sizeof(*qnp))) == NULL)
                err(1, "%s", strerror(errno));
        qnp->flags = 0;
        if (gflag && hasquota(qfnp, sizeof(qfnp), fs, GRPQUOTA)) {
                strlcpy(qnp->grpqfname, qfnp, sizeof(qnp->grpqfname));
                qnp->flags |= HASGRP;
        }
        if (uflag && hasquota(qfnp, sizeof(qfnp), fs, USRQUOTA)) {
                strlcpy(qnp->usrqfname, qfnp, sizeof(qnp->usrqfname));
                qnp->flags |= HASUSR;
        }
        if (qnp->flags)
                return (qnp);
        free(qnp);
        return (NULL);
}

static off_t sblock_try[] = SBLOCKSEARCH;

/*
 * Scan the specified filesystem to check quota(s) present on it.
 */
static int
chkquota(const char *type, const char *fsname, const char *mntpt, void *v,
    pid_t *pid)
{
        struct quotaname *qnp = v;
        struct fileusage *fup;
        union comb_dinode *dp;
        int i, mode, errs = 0, inosused;
        uint32_t cg;
        ino_t ino;
        struct cg *cgp;
        char msgbuf[4096];

        if (pid != NULL) {
                fflush(stdout);
                switch ((*pid = fork())) {
                default:
                        return 0;
                case 0:
                        break;
                case -1:
                        err(1, "Cannot fork");
                }
                setvbuf(stdout, msgbuf, _IOFBF, sizeof msgbuf);
        }

        if ((fi = open(fsname, O_RDONLY, 0)) < 0) {
                warn("Cannot open %s", fsname);
                if (pid != NULL)
                        exit(1);
                return 1;
        }
        if (vflag) {
                (void)printf("*** Checking ");
                if (qnp->flags & HASUSR)
                        (void)printf("%s%s", qfextension[USRQUOTA],
                            (qnp->flags & HASGRP) ? " and " : "");
                if (qnp->flags & HASGRP)
                        (void)printf("%s", qfextension[GRPQUOTA]);
                (void)printf(" quotas for %s (%s)\n", fsname, mntpt);
                fflush(stdout);
        }
        signal(SIGINFO, infohandler);
        sync();
        dev_bsize = 1;

        for (i = 0; ; i++) {
                if (sblock_try[i] == -1) {
                        warnx("%s: superblock not found", fsname);
                        if (pid != NULL)
                                exit(1);
                        return 1;
                }
                bread(sblock_try[i], (char *)&sblock, SBLOCKSIZE);
                switch (sblock.fs_magic) {
#ifdef HAVE_UFSv2
                case FS_UFS2EA_MAGIC:
                        sblock.fs_magic = FS_UFS2_MAGIC;
                        /*FALLTHROUGH*/
                case FS_UFS2_MAGIC:
                        is_ufs2 = 1;
                        /*FALLTHROUGH*/
#endif
                case FS_UFS1_MAGIC:
                        break;
#ifdef HAVE_UFSv2
                case FS_UFS2EA_MAGIC_SWAPPED:
                        sblock.fs_magic = FS_UFS2_MAGIC_SWAPPED;
                        /*FALLTHROUGH*/
                case FS_UFS2_MAGIC_SWAPPED:
                        is_ufs2 = 1;
                        /*FALLTHROUGH*/
#endif
                case FS_UFS1_MAGIC_SWAPPED:
                        needswap = 1;
                        ffs_sb_swap(&sblock, &sblock);
                        break;
                default:
                        continue;
                }

#ifdef HAVE_UFSv2
                if (is_ufs2 || sblock.fs_old_flags & FS_FLAGS_UPDATED) {
                        if (sblock.fs_sblockloc != sblock_try[i])
                                continue;
                } else {
                        if (sblock_try[i] == SBLOCK_UFS2)
                                continue;
                }
#endif
                break;
        }

        cgp = malloc(sblock.fs_cgsize);
        if (cgp == NULL) {
                warn("%s: can't allocate %d bytes of cg space", fsname,
                    sblock.fs_cgsize);
                if (pid != NULL)
                        exit(1);
                return 1;
        }

        dev_bsize = sblock.fs_fsize / FFS_FSBTODB(&sblock, 1);
        maxino = sblock.fs_ncg * sblock.fs_ipg;
        for (cg = 0; cg < sblock.fs_ncg; cg++) {
                ino = cg * sblock.fs_ipg;
                setinodebuf(ino);
#ifdef HAVE_UFSv2
                if (sblock.fs_magic == FS_UFS2_MAGIC) {
                        bread(FFS_FSBTODB(&sblock, cgtod(&sblock, cg)), (char *)cgp,
                            sblock.fs_cgsize);
                        if (needswap)
                                ffs_cg_swap(cgp, cgp, &sblock);
                        inosused = cgp->cg_initediblk;
                } else
#endif
                        inosused = sblock.fs_ipg;
                for (i = 0; i < inosused; i++, ino++) {
                        if (got_siginfo) {
                                fprintf(stderr,
                                    "%s: cyl group %d of %d (%d%%)\n",
                                    fsname, cg, sblock.fs_ncg,
                                    cg * 100 / sblock.fs_ncg);
                                got_siginfo = 0;
                        }
                        if (ino < UFS_ROOTINO)
                                continue;
                        if ((dp = getnextinode(ino)) == NULL)
                                continue;
                        if ((mode = DIP(dp, mode) & IFMT) == 0)
                                continue;
                        if (qnp->flags & HASGRP) {
                                fup = addid(DIP(dp, gid), GRPQUOTA,
                                    (char *)0);
                                fup->fu_curinodes++;
                                if (mode == IFREG || mode == IFDIR ||
                                    mode == IFLNK)
                                        fup->fu_curblocks += DIP(dp, blocks);
                        }
                        if (qnp->flags & HASUSR) {
                                fup = addid(DIP(dp, uid), USRQUOTA,
                                    (char *)0);
                                fup->fu_curinodes++;
                                if (mode == IFREG || mode == IFDIR ||
                                    mode == IFLNK)
                                        fup->fu_curblocks += DIP(dp, blocks);
                        }
                }
        }
        freeinodebuf();
        free(cgp);
        if (qnp->flags & HASUSR)
                errs += update(mntpt, qnp->usrqfname, USRQUOTA);
        if (qnp->flags & HASGRP)
                errs += update(mntpt, qnp->grpqfname, GRPQUOTA);
        close(fi);
        if (pid != NULL)
                exit(errs);
        return errs;
}

/*
 * Update a specified quota file.
 */
static int
update(const char *fsname, const char *quotafile, int type)
{
        struct fileusage *fup;
        FILE *qfi, *qfo;
        uint32_t id, lastid, nextid;
        int need_seek;
        struct dqblk dqbuf;
        static struct dqblk zerodqbuf;
        static struct fileusage zerofileusage;
        struct statvfs *fst;
        int nfst, i;

        nfst = getmntinfo(&fst, MNT_WAIT);
        if (nfst == 0)
                errx(1, "no filesystems mounted!");

        for (i = 0; i < nfst; i++) {
                if (strncmp(fst[i].f_fstypename, "ffs",
                    sizeof(fst[i].f_fstypename)) == 0 &&
                    strncmp(fst[i].f_mntonname, fsname,
                    sizeof(fst[i].f_mntonname)) == 0 &&
                    (fst[i].f_flag & ST_QUOTA) != 0) {
                        warnx("filesystem %s has quotas already turned on",
                            fsname);
                }
        }

        if ((qfo = fopen(quotafile, "r+")) == NULL) {
                if (errno == ENOENT)
                        qfo = fopen(quotafile, "w+");
                if (qfo) {
                        (void) fprintf(stderr,
                            "quotacheck: creating quota file %s\n", quotafile);
#define MODE    (S_IRUSR|S_IWUSR|S_IRGRP)
                        (void) fchown(fileno(qfo), getuid(), getquotagid());
                        (void) fchmod(fileno(qfo), MODE);
                } else {
                        (void) fprintf(stderr,
                            "quotacheck: %s: %s\n", quotafile, strerror(errno));
                        return (1);
                }
        }
        if ((qfi = fopen(quotafile, "r")) == NULL) {
                (void) fprintf(stderr,
                    "quotacheck: %s: %s\n", quotafile, strerror(errno));
                (void) fclose(qfo);
                return (1);
        }
        need_seek = 1;
        for (lastid = highid[type], id = 0; id <= lastid; id = nextid) {
                if (fread((char *)&dqbuf, sizeof(struct dqblk), 1, qfi) == 0)
                        dqbuf = zerodqbuf;
                if ((fup = lookup(id, type)) == 0)
                        fup = &zerofileusage;

                nextid = subsequent(id, type);
                /* watch out for id == UINT32_MAX */
                if (nextid > 0 && nextid != id + 1)
                        nextid = skipforward(id, nextid, qfi);

                if (got_siginfo) {
                        /*
                         * XXX this could try to show percentage through
                         * the ID list
                         */
                        fprintf(stderr, "%s: updating %s quotas for id=%"
                            PRIu32 " (%s)\n", fsname,
                            qfextension[type < MAXQUOTAS ? type : MAXQUOTAS],
                            id, fup->fu_name);
                        got_siginfo = 0;
                }
                if (dqbuf.dqb_curinodes == fup->fu_curinodes &&
                    dqbuf.dqb_curblocks == fup->fu_curblocks) {
                        fup->fu_curinodes = 0;  /* reset usage  */
                        fup->fu_curblocks = 0;  /* for next filesystem */

                        need_seek = 1;
                        /* infinite loop avoidance (OR do as "nextid < id"?) */
                        if (id == UINT32_MAX || nextid == 0) {
                                break;
                        }
                        continue;
                }
                if (vflag) {
                        if (aflag)
                                printf("%s: ", fsname);
                        printf("%-8s fixed:", fup->fu_name);
                        if (dqbuf.dqb_curinodes != fup->fu_curinodes)
                                (void)printf("\tinodes %d -> %ld",
                                        dqbuf.dqb_curinodes, fup->fu_curinodes);
                        if (dqbuf.dqb_curblocks != fup->fu_curblocks)
                                (void)printf("\tblocks %d -> %ld",
                                        dqbuf.dqb_curblocks, fup->fu_curblocks);
                        (void)printf("\n");
                }
                /*
                 * Reset time limit if have a soft limit and were
                 * previously under it, but are now over it.
                 */
                if (dqbuf.dqb_bsoftlimit &&
                    dqbuf.dqb_curblocks < dqbuf.dqb_bsoftlimit &&
                    fup->fu_curblocks >= dqbuf.dqb_bsoftlimit)
                        dqbuf.dqb_btime = 0;
                if (dqbuf.dqb_isoftlimit &&
                    dqbuf.dqb_curinodes < dqbuf.dqb_isoftlimit &&
                    fup->fu_curinodes >= dqbuf.dqb_isoftlimit)
                        dqbuf.dqb_itime = 0;
                dqbuf.dqb_curinodes = fup->fu_curinodes;
                dqbuf.dqb_curblocks = fup->fu_curblocks;

                if (need_seek) {
                        (void) fseeko(qfo, (off_t)id * sizeof(struct dqblk),
                            SEEK_SET);
                        need_seek = nextid != id + 1;
                }
                (void) fwrite(&dqbuf, sizeof(struct dqblk), 1, qfo);

                fup->fu_curinodes = 0;
                fup->fu_curblocks = 0;
                /* infinite loop avoidance (OR do as "nextid < id"?) */
                if (id == UINT32_MAX || nextid == 0) {
                        break;
                }
        }
        (void)fclose(qfi);
        (void)fflush(qfo);
        if (highid[type] != UINT32_MAX)
                (void)ftruncate(fileno(qfo),
                    (off_t)((highid[type] + 1) * sizeof(struct dqblk)));
        (void)fclose(qfo);
        return 0;
}

static uint32_t
skipforward(uint32_t cur, uint32_t to, FILE *qfi)
{
        struct dqblk dqbuf;

        if (qflag) {
                (void)fseeko(qfi, (off_t)to * sizeof(struct dqblk), SEEK_SET);
                return to;
        }

        while (++cur < to) {
                /*
                 * if EOF occurs, nothing left to read, we're done
                 */
                if (fread((char *)&dqbuf, sizeof(struct dqblk), 1, qfi) == 0)
                        return (to);

                /*
                 * If we find an entry that shows usage, before the next
                 * id that has actual usage, we have to stop here, so the
                 * incorrect entry can be corrected in the file
                 */
                if (dqbuf.dqb_curinodes != 0 || dqbuf.dqb_curblocks != 0) {
                        (void)fseek(qfi, -(long)sizeof(struct dqblk), SEEK_CUR);
                        return cur;
                }
        }
        return to;
}

/*
 * Determine the group identifier for quota files.
 */
static int
getquotagid(void)
{
        struct group *gr;

        if ((gr = getgrnam(quotagroup)) != NULL)
                return gr->gr_gid;
        return -1;
}

/*
 * Routines to manage the file usage table.
 *
 * Lookup an id of a specific type.
 */
static struct fileusage *
lookup(uint32_t id, int type)
{
        struct fileusage *fup;

        for (fup = fuhead[type][id & (FUHASH-1)]; fup != 0; fup = fup->fu_next)
                if (fup->fu_id == id)
                        return fup;
        return NULL;
}

/*
 * Add a new file usage id if it does not already exist.
 */
static struct fileusage *
addid(uint32_t id, int type, const char *name)
{
        struct fileusage *fup, **fhp;
        size_t len;

        if ((fup = lookup(id, type)) != NULL)
                return fup;
        if (name)
                len = strlen(name);
        else
                len = 10;
        if ((fup = calloc(1, sizeof(*fup) + len)) == NULL)
                err(1, "%s", strerror(errno));
        fhp = &fuhead[type][id & (FUHASH - 1)];
        fup->fu_next = *fhp;
        *fhp = fup;
        fup->fu_id = id;
        if (id > highid[type])
                highid[type] = id;
        if (name)
                memmove(fup->fu_name, name, len + 1);
        else
                (void)snprintf(fup->fu_name, len + 1, "%" PRIu32, id);
        return fup;
}

static uint32_t
subsequent(uint32_t id, int type)
{
        struct fileusage *fup, **iup, **cup;
        uint32_t next, offset;

        next = highid[type] + 1;
        offset = 0;
        cup = iup = &fuhead[type][id & (FUHASH-1)];
        do {
                ++offset;
                if (++cup >= &fuhead[type][FUHASH])
                        cup = &fuhead[type][0];
                for (fup = *cup; fup != 0; fup = fup->fu_next) {
                        if (fup->fu_id > id && fup->fu_id <= id + offset)
                                return (fup->fu_id);
                        if (fup->fu_id > id && fup->fu_id < next)
                                next = fup->fu_id;
                }
        } while (cup != iup);

        return next;
}

/*
 * Special purpose version of ginode used to optimize first pass
 * over all the inodes in numerical order.
 */
static ino_t nextino, lastinum, lastvalidinum;
static long readcnt, readpercg, fullcnt, inobufsize, partialcnt, partialsize;
static union comb_dinode *inodebuf;
#define INOBUFSIZE      56*1024 /* size of buffer to read inodes */

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

        if (inumber != nextino++ || inumber > lastvalidinum) {
                errx(1, "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(dblk, (caddr_t)inodebuf, size);
                if (needswap) {
#ifdef HAVE_UFSv2
                        if (is_ufs2)
                                swap_dinode2(inodebuf, lastinum - inumber);
                        else
#endif
                                swap_dinode1(inodebuf, lastinum - inumber);
                }
                dp = (union comb_dinode *)inodebuf;
        }
        ret = dp;
        dp = (union comb_dinode *)
            ((char *)dp + (is_ufs2 ? DINODE2_SIZE : DINODE1_SIZE));
        return ret;
}

static void
setinodebuf(ino_t inum)
{

        if (inum % sblock.fs_ipg != 0)
                errx(1, "bad inode number %llu to setinodebuf",
                    (unsigned long long)inum);

        lastvalidinum = inum + sblock.fs_ipg - 1;
        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 = malloc((unsigned)inobufsize)) == NULL)
                errx(1, "Cannot allocate space for inode buffer");
        while (nextino < UFS_ROOTINO)
                getnextinode(nextino);
}

static void
freeinodebuf(void)
{

        free(inodebuf);
        inodebuf = NULL;
}


#ifdef HAVE_UFSv2
static void
swap_dinode1(union comb_dinode *dp, int n)
{
        int i;
        struct ufs1_dinode *dp1;

        dp1 = (struct ufs1_dinode *)&dp->dp1;
        for (i = 0; i < n; i++, dp1++)
                ffs_dinode1_swap(dp1, dp1);
}

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

        dp2 = (struct ufs2_dinode *)&dp->dp2;
        for (i = 0; i < n; i++, dp2++)
                ffs_dinode2_swap(dp2, dp2);
}

#else

static void
swap_dinode1(union comb_dinode *dp, int n)
{
        int i;
        struct dinode *dp1;

        dp1 = (struct dinode *) &dp->dp1;
        for (i = 0; i < n; i++, dp1++)
                ffs_dinode_swap(dp1, dp1);
}

#endif

/*
 * Read specified disk blocks.
 */
static void
bread(daddr_t bno, char *buf, long cnt)
{

        if (lseek(fi, (off_t)bno * dev_bsize, SEEK_SET) < 0 ||
            read(fi, buf, cnt) != cnt)
                err(1, "block %lld", (long long)bno);
}

static void    
infohandler(int sig)
{
        got_siginfo = 1;
}