/*      $OpenBSD: df.c,v 1.63 2026/01/09 19:54:57 job Exp $     */
/*      $NetBSD: df.c,v 1.21.2.1 1995/11/01 00:06:11 jtc Exp $  */

/*
 * Copyright (c) 1980, 1990, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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/stat.h>
#include <sys/mount.h>

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

int              bread(int, off_t, void *, int);
static void      bsdprint(struct statfs *, long, int);
char            *getmntpt(char *);
static void      maketypelist(char *);
static int       percent(u_int64_t, u_int64_t);
static void      posixprint(struct statfs *, long, int);
static void      prthuman(struct statfs *sfsp, unsigned long long);
static void      prthumanval(long long);
static void      prtstat(struct statfs *, int, int, int);
static long      regetmntinfo(struct statfs **, long);
static int       selected(const char *);
static __dead void usage(void);

extern int       e2fs_df(int, char *, struct statfs *);
extern int       ffs_df(int, char *, struct statfs *);
static int       raw_df(char *, struct statfs *);

int     hflag, iflag, kflag, lflag, nflag, Pflag;
char    **typelist = NULL;

int
main(int argc, char *argv[])
{
        struct stat stbuf;
        struct statfs *mntbuf;
        long mntsize;
        int ch, i;
        int width, maxwidth;
        char *mntpt;

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

        while ((ch = getopt(argc, argv, "hiklnPt:")) != -1)
                switch (ch) {
                case 'h':
                        hflag = 1;
                        kflag = 0;
                        break;
                case 'i':
                        iflag = 1;
                        break;
                case 'k':
                        kflag = 1;
                        hflag = 0;
                        break;
                case 'l':
                        lflag = 1;
                        break;
                case 'n':
                        nflag = 1;
                        break;
                case 'P':
                        Pflag = 1;
                        break;
                case 't':
                        if (typelist != NULL)
                                errx(1, "only one -t option may be specified.");
                        maketypelist(optarg);
                        break;
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if ((iflag || hflag) && Pflag) {
                warnx("-h and -i are incompatible with -P");
                usage();
        }

        mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
        if (mntsize == 0)
                err(1, "retrieving information on mounted file systems");

        if (!*argv) {
                mntsize = regetmntinfo(&mntbuf, mntsize);
        } else {
                mntbuf = calloc(argc, sizeof(struct statfs));
                if (mntbuf == NULL)
                        err(1, NULL);
                mntsize = 0;
                for (; *argv; argv++) {
                        if (stat(*argv, &stbuf) == -1) {
                                if ((mntpt = getmntpt(*argv)) == 0) {
                                        warn("%s", *argv);
                                        continue;
                                }
                        } else if (S_ISCHR(stbuf.st_mode) || S_ISBLK(stbuf.st_mode)) {
                                if (!raw_df(*argv, &mntbuf[mntsize]))
                                        ++mntsize;
                                continue;
                        } else
                                mntpt = *argv;
                        /*
                         * Statfs does not take a `wait' flag, so we cannot
                         * implement nflag here.
                         */
                        if (!statfs(mntpt, &mntbuf[mntsize]))
                                if (lflag && (mntbuf[mntsize].f_flags & MNT_LOCAL) == 0)
                                        warnx("%s is not a local file system",
                                            *argv);
                                else if (!selected(mntbuf[mntsize].f_fstypename))
                                        warnx("%s mounted as a %s file system",
                                            *argv, mntbuf[mntsize].f_fstypename);
                                else
                                        ++mntsize;
                        else
                                warn("%s", *argv);
                }
        }

        if (mntsize) {
                maxwidth = 11;
                for (i = 0; i < mntsize; i++) {
                        width = strlen(mntbuf[i].f_mntfromname);
                        if (width > maxwidth)
                                maxwidth = width;
                }

                if (Pflag)
                        posixprint(mntbuf, mntsize, maxwidth);
                else
                        bsdprint(mntbuf, mntsize, maxwidth);
        }

        return (mntsize ? 0 : 1);
}

char *
getmntpt(char *name)
{
        long mntsize, i;
        struct statfs *mntbuf;

        mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
        for (i = 0; i < mntsize; i++) {
                if (!strcmp(mntbuf[i].f_mntfromname, name))
                        return (mntbuf[i].f_mntonname);
        }
        return (0);
}

static enum { IN_LIST, NOT_IN_LIST } which;

static int
selected(const char *type)
{
        char **av;

        /* If no type specified, it's always selected. */
        if (typelist == NULL)
                return (1);
        for (av = typelist; *av != NULL; ++av)
                if (!strncmp(type, *av, MFSNAMELEN))
                        return (which == IN_LIST ? 1 : 0);
        return (which == IN_LIST ? 0 : 1);
}

static void
maketypelist(char *fslist)
{
        int i;
        char *nextcp, **av;

        if ((fslist == NULL) || (fslist[0] == '\0'))
                errx(1, "empty type list");

        /*
         * XXX
         * Note: the syntax is "noxxx,yyy" for no xxx's and
         * no yyy's, not the more intuitive "noyyy,noyyy".
         */
        if (fslist[0] == 'n' && fslist[1] == 'o') {
                fslist += 2;
                which = NOT_IN_LIST;
        } else
                which = IN_LIST;

        /* Count the number of types. */
        for (i = 1, nextcp = fslist; (nextcp = strchr(nextcp, ',')) != NULL; i++)
                ++nextcp;

        /* Build an array of that many types. */
        if ((av = typelist = calloc(i + 1, sizeof(char *))) == NULL)
                err(1, NULL);
        av[0] = fslist;
        for (i = 1, nextcp = fslist; (nextcp = strchr(nextcp, ',')) != NULL; i++) {
                *nextcp = '\0';
                av[i] = ++nextcp;
        }
        /* Terminate the array. */
        av[i] = NULL;
}

/*
 * Make a pass over the filesystem info in ``mntbuf'' filtering out
 * filesystem types not in ``fsmask'' and possibly re-stating to get
 * current (not cached) info.  Returns the new count of valid statfs bufs.
 */
static long
regetmntinfo(struct statfs **mntbufp, long mntsize)
{
        int i, j;
        struct statfs *mntbuf;

        if (!lflag && typelist == NULL)
                return (nflag ? mntsize : getmntinfo(mntbufp, MNT_WAIT));

        mntbuf = *mntbufp;
        j = 0;
        for (i = 0; i < mntsize; i++) {
                if (lflag && (mntbuf[i].f_flags & MNT_LOCAL) == 0)
                        continue;
                if (!selected(mntbuf[i].f_fstypename))
                        continue;
                if (nflag)
                        mntbuf[j] = mntbuf[i];
                else
                        (void)statfs(mntbuf[i].f_mntonname, &mntbuf[j]);
                j++;
        }
        return (j);
}

/*
 * "human-readable" output: use 3 digits max.--put unit suffixes at
 * the end.  Makes output compact and easy-to-read esp. on huge disks.
 * Code moved into libutil; this is now just a wrapper.
 */
static void
prthumanval(long long bytes)
{
        char ret[FMT_SCALED_STRSIZE];

        if (fmt_scaled(bytes, ret) == -1) {
                (void)printf(" %lld", bytes);
                return;
        }
        (void)printf(" %7s", ret);
}

static void
prthuman(struct statfs *sfsp, unsigned long long used)
{
        prthumanval(sfsp->f_blocks * sfsp->f_bsize);
        prthumanval(used * sfsp->f_bsize);
        prthumanval(sfsp->f_bavail * sfsp->f_bsize);
}

/*
 * Human readable output using SI symbols and multiples of thousand.
 */
static const struct scale {
        char symbol;
        unsigned long long factor;
} scale[] = {
        { ' ', 1LL },
        { 'k', 1000LL },                                        /* kilo */
        { 'M', 1000LL * 1000 },                                 /* mega */
        { 'G', 1000LL * 1000 * 1000 },                          /* giga */
        { 'T', 1000LL * 1000 * 1000 * 1000 },                   /* tera */
        { 'P', 1000LL * 1000 * 1000 * 1000 * 1000 },            /* peta */
        { 'E', 1000LL * 1000 * 1000 * 1000 * 1000 * 1000 }      /*  exa */
};
#define SCALE_LENGTH    (sizeof(scale) / sizeof(scale[0]))

static void
prtscaleddecimal(unsigned long long num)
{
        long long fract = 0;
        unsigned long i;
        int unit = 0;

        if (num < 1000 || num / 1000 >= scale[SCALE_LENGTH - 1].factor) {
                (void)printf(" %6llu", num);
                return;
        }

        for (i = 0; i < SCALE_LENGTH; i++) {
                if (num / 1000 < scale[i].factor) {
                        unit = i;
                        fract = (i == 0) ? 0 : num % scale[i].factor;
                        num /= scale[i].factor;
                        if (i > 0)
                                fract /= scale[i - 1].factor;
                        break;
                }
        }

        fract = (10 * fract + 500) / 1000;
        if (fract >= 10) {
                num++;
                fract = 0;
        }

        if (num >= 100) {
                if (fract >= 5)
                        num++;
                (void)printf(" %5llu%c", num, scale[unit].symbol);
        } else
                (void)printf(" %3llu.%1llu%c", num, fract, scale[unit].symbol);
}

/*
 * Convert statfs returned filesystem size into BLOCKSIZE units.
 * Attempts to avoid overflow for large filesystems.
 */
#define fsbtoblk(num, fsbs, bs) \
        (((fsbs) != 0 && (fsbs) < (bs)) ? \
                (num) / ((bs) / (fsbs)) : (num) * ((fsbs) / (bs)))

/*
 * Print out status about a filesystem.
 */
static void
prtstat(struct statfs *sfsp, int maxwidth, int headerlen, int blocksize)
{
        u_int64_t used, inodes;
        int64_t availblks;

        (void)printf("%-*.*s", maxwidth, maxwidth, sfsp->f_mntfromname);
        used = sfsp->f_blocks - sfsp->f_bfree;
        availblks = sfsp->f_bavail + used;
        if (hflag)
                prthuman(sfsp, used);
        else
                (void)printf(" %*llu %9llu %9lld", headerlen,
                    fsbtoblk(sfsp->f_blocks, sfsp->f_bsize, blocksize),
                    fsbtoblk(used, sfsp->f_bsize, blocksize),
                    fsbtoblk(sfsp->f_bavail, sfsp->f_bsize, blocksize));
        (void)printf(" %5d%%", percent(used, availblks));
        if (iflag) {
                inodes = sfsp->f_files;
                used = inodes - sfsp->f_ffree;

                if (hflag) {
                        (void)printf(" ");
                        prtscaleddecimal(used);
                        prtscaleddecimal(sfsp->f_ffree);
                        (void)printf(" %4d%% ", percent(used, inodes));
                } else {
                        (void)printf(" %8llu %8llu %4d%% ", used, sfsp->f_ffree,
                           percent(used, inodes));
                }
        } else
                (void)printf("  ");
        (void)printf("  %s\n", sfsp->f_mntonname);
}

/*
 * Print in traditional BSD format.
 */
static void
bsdprint(struct statfs *mntbuf, long mntsize, int maxwidth)
{
        int i;
        char *header;
        int headerlen;
        long blocksize;

        /* Print the header line */
        if (hflag) {
                header = "   Size";
                headerlen = strlen(header);
                (void)printf("%-*.*s %s    Used   Avail Capacity",
                             maxwidth, maxwidth, "Filesystem", header);
        } else {
                if (kflag) {
                        blocksize = 1024;
                        header = "1K-blocks";
                        headerlen = strlen(header);
                } else
                        header = getbsize(&headerlen, &blocksize);
                (void)printf("%-*.*s %s      Used     Avail Capacity",
                             maxwidth, maxwidth, "Filesystem", header);
        }
        if (iflag) {
                if (hflag)
                        (void)printf(" iused  ifree %%iused");
                else
                        (void)printf("  iused    ifree %%iused");
        }
        (void)printf("  Mounted on\n");


        for (i = 0; i < mntsize; i++)
                prtstat(&mntbuf[i], maxwidth, headerlen, blocksize);
        return;
}

static int
percent(u_int64_t used, u_int64_t avail)
{
        return avail ? (100 * used + (avail - 1)) / avail : 100;
}

/*
 * Print in format defined by POSIX 1002.2, invoke with -P option.
 */
static void
posixprint(struct statfs *mntbuf, long mntsize, int maxwidth)
{
        int i;
        int blocksize;
        char *blockstr;
        struct statfs *sfsp;
        long long used, avail;

        if (kflag) {
                blocksize = 1024;
                blockstr = "1024-blocks";
        } else {
                blocksize = 512;
                blockstr = " 512-blocks";
        }

        (void)printf(
            "%-*.*s %s       Used   Available Capacity Mounted on\n",
            maxwidth, maxwidth, "Filesystem", blockstr);

        for (i = 0; i < mntsize; i++) {
                sfsp = &mntbuf[i];
                used = sfsp->f_blocks - sfsp->f_bfree;
                avail = sfsp->f_bavail + used;

                (void) printf ("%-*.*s %*lld %10lld %11lld %5d%%   %s\n",
                        maxwidth, maxwidth, sfsp->f_mntfromname,
                        (int)strlen(blockstr),
                        fsbtoblk(sfsp->f_blocks, sfsp->f_bsize, blocksize),
                        fsbtoblk(used, sfsp->f_bsize, blocksize),
                        fsbtoblk(sfsp->f_bavail, sfsp->f_bsize, blocksize),
                        percent(used, avail), sfsp->f_mntonname);
        }
}

static int
raw_df(char *file, struct statfs *sfsp)
{
        int rfd, ret = -1;

        if ((rfd = open(file, O_RDONLY)) == -1) {
                warn("%s", file);
                return (-1);
        }

        if (ffs_df(rfd, file, sfsp) == 0) {
                ret = 0;
        } else if (e2fs_df(rfd, file, sfsp) == 0) {
                ret = 0;
        }

        close (rfd);
        return (ret);
}

int
bread(int rfd, off_t off, void *buf, int cnt)
{
        int nr;

        if ((nr = pread(rfd, buf, cnt, off)) != cnt) {
                /* Probably a dismounted disk if errno == EIO. */
                if (errno != EIO)
                        (void)fprintf(stderr, "\ndf: %lld: %s\n",
                            (long long)off, strerror(nr > 0 ? EIO : errno));
                return (0);
        }
        return (1);
}

static __dead void
usage(void)
{
        (void)fprintf(stderr,
            "usage: %s [-hiklnP] [-t type] [[file | file_system] ...]\n",
            getprogname());
        exit(1);
}