1/* vi: set sw=4 ts=4: */
2/*
3 * Mini df implementation for busybox
4 *
5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
6 * based on original code by (I think) Bruce Perens <bruce@pixar.com>.
7 *
8 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9 */
10
11/* BB_AUDIT SUSv3 _NOT_ compliant -- options -P and -t missing.  Also blocksize. */
12/* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */
13
14/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
15 *
16 * Size reduction.  Removed floating point dependency.  Added error checking
17 * on output.  Output stats on 0-sized filesystems if specifically listed on
18 * the command line.  Properly round *-blocks, Used, and Available quantities.
19 */
20
21#include <mntent.h>
22#include <sys/vfs.h>
23#include "libbb.h"
24
25#if !ENABLE_FEATURE_HUMAN_READABLE
26static unsigned long kscale(unsigned long b, unsigned long bs)
27{
28	return (b * (unsigned long long) bs + 1024/2) / 1024;
29}
30#endif
31
32int df_main(int argc, char **argv);
33int df_main(int argc, char **argv)
34{
35	unsigned long blocks_used;
36	unsigned blocks_percent_used;
37#if ENABLE_FEATURE_HUMAN_READABLE
38	unsigned df_disp_hr = 1024;
39#endif
40	int status = EXIT_SUCCESS;
41	unsigned opt;
42	FILE *mount_table;
43	struct mntent *mount_entry;
44	struct statfs s;
45	/* default display is kilobytes */
46	const char *disp_units_hdr = "1k-blocks";
47
48#if ENABLE_FEATURE_HUMAN_READABLE
49	opt_complementary = "h-km:k-hm:m-hk";
50	opt = getopt32(argv, "hmk");
51	if (opt & 1) {
52		df_disp_hr = 0;
53		disp_units_hdr = "     Size";
54	}
55	if (opt & 2) {
56		df_disp_hr = 1024*1024;
57		disp_units_hdr = "1M-blocks";
58	}
59#else
60	opt = getopt32(argv, "k");
61#endif
62
63	printf("Filesystem%11s%-15sUsed Available Use%% Mounted on\n",
64			  "", disp_units_hdr);
65
66	mount_table = NULL;
67	argv += optind;
68	if (optind >= argc) {
69		mount_table = setmntent(bb_path_mtab_file, "r");
70		if (!mount_table) {
71			bb_perror_msg_and_die(bb_path_mtab_file);
72		}
73	}
74
75	while (1) {
76		const char *device;
77		const char *mount_point;
78
79		if (mount_table) {
80			mount_entry = getmntent(mount_table);
81			if (!mount_entry) {
82				endmntent(mount_table);
83				break;
84			}
85		} else {
86			mount_point = *argv++;
87			if (!mount_point) {
88				break;
89			}
90			mount_entry = find_mount_point(mount_point, bb_path_mtab_file);
91			if (!mount_entry) {
92				bb_error_msg("%s: can't find mount point", mount_point);
93 SET_ERROR:
94				status = EXIT_FAILURE;
95				continue;
96			}
97		}
98
99		device = mount_entry->mnt_fsname;
100		mount_point = mount_entry->mnt_dir;
101
102		if (statfs(mount_point, &s) != 0) {
103			bb_perror_msg("%s", mount_point);
104			goto SET_ERROR;
105		}
106
107		if ((s.f_blocks > 0) || !mount_table){
108			blocks_used = s.f_blocks - s.f_bfree;
109			blocks_percent_used = 0;
110			if (blocks_used + s.f_bavail) {
111				blocks_percent_used = (blocks_used * 100ULL
112						+ (blocks_used + s.f_bavail)/2
113						) / (blocks_used + s.f_bavail);
114			}
115
116			if (strcmp(device, "rootfs") == 0) {
117				continue;
118			} else if (strcmp(device, "/dev/root") == 0) {
119				/* Adjusts device to be the real root device,
120				* or leaves device alone if it can't find it */
121				device = find_block_device("/");
122				if (!device) {
123					goto SET_ERROR;
124				}
125			}
126
127			if (printf("\n%-20s" + 1, device) > 20)
128				    printf("\n%-20s", "");
129#if ENABLE_FEATURE_HUMAN_READABLE
130			printf(" %9s ",
131				make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));
132
133			printf(" %9s " + 1,
134				make_human_readable_str((s.f_blocks - s.f_bfree),
135						s.f_bsize, df_disp_hr));
136
137			printf("%9s %3u%% %s\n",
138					make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
139					blocks_percent_used, mount_point);
140#else
141			printf(" %9lu %9lu %9lu %3u%% %s\n",
142					kscale(s.f_blocks, s.f_bsize),
143					kscale(s.f_blocks-s.f_bfree, s.f_bsize),
144					kscale(s.f_bavail, s.f_bsize),
145					blocks_percent_used, mount_point);
146#endif
147		}
148	}
149
150	fflush_stdout_and_exit(status);
151}
152