df.c

/* vi: set sw=4 ts=4: */
/*
 * Mini df implementation for busybox
 *
 * Copyright (C) 1999 by Lineo, inc.
 * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
 * based on original code by (I think) Bruce Perens <bruce@pixar.com>.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include "internal.h"
#include <stdio.h>
#include <mntent.h>
#include <sys/stat.h>
#include <sys/vfs.h>
#include <fstab.h>

static const char df_usage[] = "df [filesystem ...]\n"

	"\n" "\tPrint the filesystem space used and space available.\n";

extern const char mtab_file[];	/* Defined in utility.c */

static int df(char *device, const char *mountPoint)
{
	struct statfs s;
	long blocks_used;
	long blocks_percent_used;
	struct fstab *fstabItem;

	if (statfs(mountPoint, &s) != 0) {
		perror(mountPoint);
		return FALSE;
	}

	if (s.f_blocks > 0) {
		blocks_used = s.f_blocks - s.f_bfree;
		blocks_percent_used = (long)
			(blocks_used * 100.0 / (blocks_used + s.f_bavail) + 0.5);
		/* Note that if /etc/fstab is missing, libc can't fix up /dev/root for us */
		if (strcmp(device, "/dev/root") == 0) {
			fstabItem = getfsfile("/");
			if (fstabItem != NULL)
				device = fstabItem->fs_spec;
		}
		printf("%-20s %9ld %9ld %9ld %3ld%% %s\n",
			   device,
			   (long) (s.f_blocks * (s.f_bsize / 1024.0)),
			   (long) ((s.f_blocks - s.f_bfree) * (s.f_bsize / 1024.0)),
			   (long) (s.f_bavail * (s.f_bsize / 1024.0)),
			   blocks_percent_used, mountPoint);

	}

	return TRUE;
}

extern int df_main(int argc, char **argv)
{
	printf("%-20s %-14s %s %s %s %s\n", "Filesystem",
		   "1k-blocks", "Used", "Available", "Use%", "Mounted on");

	if (argc > 1) {
		struct mntent *mountEntry;
		int status;

		while (argc > 1) {
			if ((mountEntry = findMountPoint(argv[1], mtab_file)) == 0) {
				fprintf(stderr, "%s: can't find mount point.\n", argv[1]);
				exit(FALSE);
			}
			status = df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
			if (status != 0)
				exit(status);
			argc--;
			argv++;
		}
		exit(TRUE);
	} else {
		FILE *mountTable;
		struct mntent *mountEntry;

		mountTable = setmntent(mtab_file, "r");
		if (mountTable == 0) {
			perror(mtab_file);
			exit(FALSE);
		}

		while ((mountEntry = getmntent(mountTable))) {
			df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
		}
		endmntent(mountTable);
	}

	exit(TRUE);
}