summaryrefslogtreecommitdiff
path: root/df.c
blob: bbda694567bbd18f41734b1827c8aa905703f81a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
#include "internal.h"
#include <stdio.h>
#include <mntent.h>
#include <sys/stat.h>
#include <sys/vfs.h>

const char	df_usage[] = "df [filesystem ...]\n"
"\n"
"\tPrint the filesystem space used and space available.\n";


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

	if ( statfs(mountPoint, &s) != 0 ) {
		perror(mountPoint);
		return 1;
	}
	
	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);

/*
		printf(
		 "%-20s %7ld %7ld  %7ld  %5ld%%   %s\n"
		,device
		,s.f_blocks
		,s.f_blocks - s.f_bfree
		,s.f_bavail
		,blocks_percent_used
		,mountPoint);
*/

		printf(
		       "%-20s %7.0f %7.0f  %7.0f  %5ld%%   %s\n"
		       ,device
		       ,s.f_blocks * (s.f_bsize / 1024.0)
		       ,(s.f_blocks - s.f_bfree)  * (s.f_bsize / 1024.0)
		       ,s.f_bavail * (s.f_bsize / 1024.0)
		       ,blocks_percent_used
		       ,mountPoint);

	}

	return 0;
}

extern int
df_main(int argc, char * * argv)
{
	static const char header[] =
	 "Filesystem         1024-blocks  Used Available Capacity Mounted on\n";
	printf(header);

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

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

		if ( (mountTable = setmntent("/proc/mounts", "r")) == 0) {
			perror("/proc/mounts");
			return 1;
		}

		while ( (mountEntry = getmntent(mountTable)) != 0 ) {
			int status = df(
			 mountEntry->mnt_fsname
			,mountEntry->mnt_dir);
			if ( status != 0 )
				return status;
		}
		endmntent(mountTable);
	}
	
	return 0;
}




/*
 * Given a block device, find the mount table entry if that block device
 * is mounted.
 *
 * Given any other file (or directory), find the mount table entry for its
 * filesystem.
 */
extern struct mntent *
findMountPoint(const char * name, const char * table)
{
	struct stat	s;
	dev_t			mountDevice;
	FILE *			mountTable;
	struct mntent *	mountEntry;

	if ( stat(name, &s) != 0 )
		return 0;

	if ( (s.st_mode & S_IFMT) == S_IFBLK )
		mountDevice = s.st_rdev;
	else
		mountDevice = s.st_dev;

	
	if ( (mountTable = setmntent(table, "r")) == 0 )
		return 0;

	while ( (mountEntry = getmntent(mountTable)) != 0 ) {
		if ( strcmp(name, mountEntry->mnt_dir) == 0
		 || strcmp(name, mountEntry->mnt_fsname) == 0 )	/* String match. */
			break;
		if ( stat(mountEntry->mnt_fsname, &s) == 0
		 && s.st_rdev == mountDevice )	/* Match the device. */
				break;
		if ( stat(mountEntry->mnt_dir, &s) == 0
		 && s.st_dev == mountDevice )	/* Match the directory's mount point. */
			break;
	}
	endmntent(mountTable);
	return mountEntry;
}