/*	$OpenBSD: df.c,v 1.4 1996/08/02 12:40:53 deraadt 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1980, 1990, 1993, 1994\n\
	The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)df.c	8.7 (Berkeley) 4/2/94";
#else
static char rcsid[] = "$OpenBSD: df.c,v 1.4 1996/08/02 12:40:53 deraadt Exp $";
#endif
#endif /* not lint */

#include <sys/param.h>
#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>

int	 bread __P((off_t, void *, int));
char	*getmntpt __P((char *));
void	 prtstat __P((struct statfs *, int));
int	 ufs_df __P((char *, struct statfs *));
int	 selected __P((const char *));
void	 maketypelist __P((char *));
long	 regetmntinfo __P((struct statfs **, long));
void	 usage __P((void));

int	iflag, kflag, lflag, nflag;
char	**typelist = NULL;
struct	ufs_args mdev;

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

	while ((ch = getopt(argc, argv, "iklnt:")) != -1)
		switch (ch) {
		case 'i':
			iflag = 1;
			break;
		case 'k':
			kflag = 1;
			break;
		case 'l':
			lflag = 1;
			break;
		case 'n':
			nflag = 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 (*argv && (lflag || typelist != NULL))
		errx(1, "-l or -t does not make sense with list of mount points");

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

	if (!*argv) {
		mntsize = regetmntinfo(&mntbuf, mntsize);
	} else {
		mntbuf = malloc(argc * sizeof(struct statfs));
		mntsize = 0;
		for (; *argv; argv++) {
			if (stat(*argv, &stbuf) < 0) {
				if ((mntpt = getmntpt(*argv)) == 0) {
					warn("%s", *argv);
					continue;
				}
			} else if (S_ISCHR(stbuf.st_mode)) {
				if (!ufs_df(*argv, &mntbuf[mntsize]))
					++mntsize;
				continue;
			} else if (S_ISBLK(stbuf.st_mode)) {
				if ((mntpt = getmntpt(*argv)) == 0) {
					mntpt = mktemp(strdup("/tmp/df.XXXXXX"));
					mdev.fspec = *argv;
					if (mkdir(mntpt, DEFFILEMODE) != 0) {
						warn("%s", mntpt);
						continue;
					}
					if (mount(MOUNT_FFS, mntpt, MNT_RDONLY,
					    &mdev) != 0) {
						(void)rmdir(mntpt);
						if (!ufs_df(*argv, &mntbuf[mntsize]))
							++mntsize;
						continue;
					} else if (!statfs(mntpt, &mntbuf[mntsize])) {
						mntbuf[mntsize].f_mntonname[0] = '\0';
						++mntsize;
					} else
						warn("%s", *argv);
					(void)unmount(mntpt, 0);
					(void)rmdir(mntpt);
					continue;
				}
			} else
				mntpt = *argv;
			/*
			 * Statfs does not take a `wait' flag, so we cannot
			 * implement nflag here.
			 */
			if (!statfs(mntpt, &mntbuf[mntsize]))
				++mntsize;
			else
				warn("%s", *argv);
		}
	}

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

char *
getmntpt(name)
	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;

int
selected(type)
	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);
}

void
maketypelist(fslist)
	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, ','); i++)
		++nextcp;

	/* Build an array of that many types. */
	if ((av = typelist = malloc((i + 1) * sizeof(char *))) == NULL)
		err(1, NULL);
	av[0] = fslist;
	for (i = 1, nextcp = fslist; nextcp = strchr(nextcp, ','); 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.
 */
long
regetmntinfo(mntbufp, mntsize)
	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);
}

/*
 * 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.
 */
void
prtstat(sfsp, maxwidth)
	struct statfs *sfsp;
	int maxwidth;
{
	static long blocksize;
	static int headerlen, timesthrough;
	static char *header;
	long used, availblks, inodes;

	if (maxwidth < 11)
		maxwidth = 11;
	if (++timesthrough == 1) {
		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)
			(void)printf(" iused   ifree  %%iused");
		(void)printf("  Mounted on\n");
	}
	(void)printf("%-*.*s", maxwidth, maxwidth, sfsp->f_mntfromname);
	used = sfsp->f_blocks - sfsp->f_bfree;
	availblks = sfsp->f_bavail + used;
	(void)printf(" %*ld %8ld %8ld", 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(" %5.0f%%",
	    availblks == 0 ? 100.0 : (double)used / (double)availblks * 100.0);
	if (iflag) {
		inodes = sfsp->f_files;
		used = inodes - sfsp->f_ffree;
		(void)printf(" %7ld %7ld %5.0f%% ", used, sfsp->f_ffree,
		   inodes == 0 ? 100.0 : (double)used / (double)inodes * 100.0);
	} else 
		(void)printf("  ");
	(void)printf("  %s\n", sfsp->f_mntonname);
}

/*
 * This code constitutes the pre-system call Berkeley df code for extracting
 * information from filesystem superblocks.
 */
#include <ufs/ffs/fs.h>
#include <errno.h>
#include <fstab.h>

union {
	struct fs iu_fs;
	char dummy[SBSIZE];
} sb;
#define sblock sb.iu_fs

int	rfd;

int
ufs_df(file, sfsp)
	char *file;
	struct statfs *sfsp;
{
	char *mntpt;
	static int synced;

	if (synced++ == 0)
		sync();

	if ((rfd = open(file, O_RDONLY)) < 0) {
		warn("%s", file);
		return (-1);
	}
	if (bread((off_t)SBOFF, &sblock, SBSIZE) == 0) {
		(void)close(rfd);
		return (-1);
	}
	sfsp->f_type = 0;
	sfsp->f_flags = 0;
	sfsp->f_bsize = sblock.fs_fsize;
	sfsp->f_iosize = sblock.fs_bsize;
	sfsp->f_blocks = sblock.fs_dsize;
	sfsp->f_bfree = sblock.fs_cstotal.cs_nbfree * sblock.fs_frag +
		sblock.fs_cstotal.cs_nffree;
	sfsp->f_bavail = (sblock.fs_dsize * (100 - sblock.fs_minfree) / 100) -
		(sblock.fs_dsize - sfsp->f_bfree);
	if (sfsp->f_bavail < 0)
		sfsp->f_bavail = 0;
	sfsp->f_files =  sblock.fs_ncg * sblock.fs_ipg;
	sfsp->f_ffree = sblock.fs_cstotal.cs_nifree;
	sfsp->f_fsid.val[0] = 0;
	sfsp->f_fsid.val[1] = 0;
	if ((mntpt = getmntpt(file)) == 0)
		mntpt = "";
	memmove(&sfsp->f_mntonname[0], mntpt, MNAMELEN);
	memmove(&sfsp->f_mntfromname[0], file, MNAMELEN);
	strncpy(sfsp->f_fstypename, MOUNT_FFS, MFSNAMELEN);
	(void)close(rfd);
	return (0);
}

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

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

void
usage()
{
	(void)fprintf(stderr, "usage: df [-ikln] [-t type] [file | file_system ...]\n");
	exit(1);
}