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 -- option -t missing. */
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 * Aug 28, 2008      Bernhard Reutner-Fischer
21 *
22 * Implement -P and -B; better coreutils compat; cleanup
23 */
24
25#include <mntent.h>
26#include <sys/vfs.h>
27#include "libbb.h"
28#include "unicode.h"
29
30#if !ENABLE_FEATURE_HUMAN_READABLE
31static unsigned long kscale(unsigned long b, unsigned long bs)
32{
33	return (b * (unsigned long long) bs + 1024/2) / 1024;
34}
35#endif
36
37int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
38int df_main(int argc UNUSED_PARAM, char **argv)
39{
40	unsigned long blocks_used;
41	unsigned blocks_percent_used;
42	unsigned long df_disp_hr = 1024;
43	int status = EXIT_SUCCESS;
44	unsigned opt;
45	FILE *mount_table;
46	struct mntent *mount_entry;
47	struct statfs s;
48
49	enum {
50		OPT_KILO  = (1 << 0),
51		OPT_POSIX = (1 << 1),
52		OPT_ALL   = (1 << 2) * ENABLE_FEATURE_DF_FANCY,
53		OPT_INODE = (1 << 3) * ENABLE_FEATURE_DF_FANCY,
54		OPT_BSIZE = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
55		OPT_HUMAN = (1 << (2 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
56		OPT_MEGA  = (1 << (3 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
57	};
58	const char *disp_units_hdr = NULL;
59	char *chp;
60
61	init_unicode();
62
63#if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
64	opt_complementary = "k-mB:m-Bk:B-km";
65#elif ENABLE_FEATURE_HUMAN_READABLE
66	opt_complementary = "k-m:m-k";
67#endif
68	opt = getopt32(argv, "kP"
69			IF_FEATURE_DF_FANCY("aiB:")
70			IF_FEATURE_HUMAN_READABLE("hm")
71			IF_FEATURE_DF_FANCY(, &chp));
72	if (opt & OPT_MEGA)
73		df_disp_hr = 1024*1024;
74
75	if (opt & OPT_BSIZE)
76		df_disp_hr = xatoul_range(chp, 1, ULONG_MAX); /* disallow 0 */
77
78	/* From the manpage of df from coreutils-6.10:
79	   Disk space is shown in 1K blocks by default, unless the environment
80	   variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
81	*/
82	if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
83		df_disp_hr = 512;
84
85	if (opt & OPT_HUMAN) {
86		df_disp_hr = 0;
87		disp_units_hdr = "     Size";
88	}
89	if (opt & OPT_INODE)
90		disp_units_hdr = "   Inodes";
91
92	if (disp_units_hdr == NULL) {
93#if ENABLE_FEATURE_HUMAN_READABLE
94		disp_units_hdr = xasprintf("%s-blocks",
95			/* print df_disp_hr, show no fractionals,
96			 * use suffixes if OPT_POSIX is set in opt */
97			make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
98		);
99#else
100		disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
101#endif
102	}
103	printf("Filesystem           %-15sUsed Available %s Mounted on\n",
104			disp_units_hdr, (opt & OPT_POSIX) ? "Capacity" : "Use%");
105
106	mount_table = NULL;
107	argv += optind;
108	if (!argv[0]) {
109		mount_table = setmntent(bb_path_mtab_file, "r");
110		if (!mount_table)
111			bb_perror_msg_and_die(bb_path_mtab_file);
112	}
113
114	while (1) {
115		const char *device;
116		const char *mount_point;
117
118		if (mount_table) {
119			mount_entry = getmntent(mount_table);
120			if (!mount_entry) {
121				endmntent(mount_table);
122				break;
123			}
124		} else {
125			mount_point = *argv++;
126			if (!mount_point)
127				break;
128			mount_entry = find_mount_point(mount_point, 1);
129			if (!mount_entry) {
130				bb_error_msg("%s: can't find mount point", mount_point);
131 set_error:
132				status = EXIT_FAILURE;
133				continue;
134			}
135		}
136
137		device = mount_entry->mnt_fsname;
138		mount_point = mount_entry->mnt_dir;
139		if (strcmp(mount_point, "proc") == 0 || strcmp(mount_point, "ramfs") == 0)
140			continue;
141
142		if (statfs(mount_point, &s) != 0) {
143			bb_simple_perror_msg(mount_point);
144			goto set_error;
145		}
146
147		if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
148			if (opt & OPT_INODE) {
149				s.f_blocks = s.f_files;
150				s.f_bavail = s.f_bfree = s.f_ffree;
151				s.f_bsize = 1;
152
153				if (df_disp_hr)
154					df_disp_hr = 1;
155			}
156			blocks_used = s.f_blocks - s.f_bfree;
157			blocks_percent_used = 0;
158			if (blocks_used + s.f_bavail) {
159				blocks_percent_used = (blocks_used * 100ULL
160						+ (blocks_used + s.f_bavail)/2
161						) / (blocks_used + s.f_bavail);
162			}
163
164			/* GNU coreutils 6.10 skips certain mounts, try to be compatible.  */
165			if (strcmp(device, "rootfs") == 0)
166				continue;
167
168#ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
169			if (strcmp(device, "/dev/root") == 0) {
170				/* Adjusts device to be the real root device,
171				 * or leaves device alone if it can't find it */
172				device = find_block_device("/");
173				if (!device) {
174					goto set_error;
175				}
176			}
177#endif
178
179#if ENABLE_UNICODE_SUPPORT
180			{
181				uni_stat_t uni_stat;
182				char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
183				if (uni_stat.unicode_width > 20) {
184					printf("%s\n%20s", uni_dev, "");
185				} else {
186					printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
187				}
188				free(uni_dev);
189			}
190#else
191			if (printf("\n%-20s" + 1, device) > 20)
192				    printf("\n%-20s", "");
193#endif
194
195#if ENABLE_FEATURE_HUMAN_READABLE
196			printf(" %9s ",
197				/* f_blocks x f_bsize / df_disp_hr, show one fractional,
198				 * use suffixes if df_disp_hr == 0 */
199				make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));
200
201			printf(" %9s " + 1,
202				/* EXPR x f_bsize / df_disp_hr, show one fractional,
203				 * use suffixes if df_disp_hr == 0 */
204				make_human_readable_str((s.f_blocks - s.f_bfree),
205						s.f_bsize, df_disp_hr));
206
207			printf("%9s %3u%% %s\n",
208				/* f_bavail x f_bsize / df_disp_hr, show one fractional,
209				 * use suffixes if df_disp_hr == 0 */
210				make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
211				blocks_percent_used, mount_point);
212#else
213			printf(" %9lu %9lu %9lu %3u%% %s\n",
214				kscale(s.f_blocks, s.f_bsize),
215				kscale(s.f_blocks - s.f_bfree, s.f_bsize),
216				kscale(s.f_bavail, s.f_bsize),
217				blocks_percent_used, mount_point);
218#endif
219		}
220	}
221
222	return status;
223}
224