coreutils/df.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini df implementation for busybox
   4  *
   5  * Copyright (C) 1999,2000 by Lineo, inc. and Erik Andersen
   6  * Copyright (C) 1999,2000,2001 by Erik Andersen <andersee@debian.org>
   7  * based on original code by (I think) Bruce Perens <bruce@pixar.com>.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  *
  23  */
  24
  25 /* BB_AUDIT SUSv3 _NOT_ compliant -- options -P and -t missing.  Also blocksize. */
  26 /* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */
  27
  28 /* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  29  *
  30  * Size reduction.  Removed floating point dependency.  Added error checking
  31  * on output.  Output stats on 0-sized filesystems if specificly listed on
  32  * the command line.  Properly round *-blocks, Used, and Available quantities.
  33  */
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <unistd.h>
  39 #include <mntent.h>
  40 #include <sys/vfs.h>
  41 #include "busybox.h"
  42
  43 #ifndef CONFIG_FEATURE_HUMAN_READABLE
  44 static long kscale(long b, long bs)
  45 {
  46         return ( b * (long long) bs + KILOBYTE/2 ) / KILOBYTE;
  47 }
  48 #endif
  49
  50 extern int df_main(int argc, char **argv)
  51 {
  52         long blocks_used;
  53         long blocks_percent_used;
  54 #ifdef CONFIG_FEATURE_HUMAN_READABLE
  55         unsigned long df_disp_hr = KILOBYTE;
  56 #endif
  57         int status = EXIT_SUCCESS;
  58         int opt;
  59         FILE *mount_table;
  60         struct mntent *mount_entry;
  61         struct statfs s;
  62         static const char hdr_1k[] = "1k-blocks"; /* default display is kilobytes */;
  63         const char *disp_units_hdr = hdr_1k;
  64
  65         while ((opt = getopt(argc, argv, "k"
  66 #ifdef CONFIG_FEATURE_HUMAN_READABLE
  67         "hm"
  68 #endif
  69 )) > 0)
  70         {
  71                 switch (opt) {
  72 #ifdef CONFIG_FEATURE_HUMAN_READABLE
  73                         case 'h':
  74                                 df_disp_hr = 0;
  75                                 disp_units_hdr = "     Size";
  76                                 break;
  77                         case 'm':
  78                                 df_disp_hr = MEGABYTE;
  79                                 disp_units_hdr = "1M-blocks";
  80                                 break;
  81 #endif
  82                         case 'k':
  83                                 /* default display is kilobytes */
  84 #ifdef CONFIG_FEATURE_HUMAN_READABLE
  85                                 df_disp_hr = KILOBYTE;
  86                                 disp_units_hdr =  hdr_1k;
  87 #endif
  88                                 break;
  89                         default:
  90                                           bb_show_usage();
  91                 }
  92         }
  93
  94         bb_printf("Filesystem%11s%-15sUsed Available Use%% Mounted on\n",
  95                           "", disp_units_hdr);
  96
  97         mount_table = NULL;
  98         argv += optind;
  99         if (optind >= argc) {
 100                 if (!(mount_table = setmntent(bb_path_mtab_file, "r"))) {
 101                         bb_perror_msg_and_die(bb_path_mtab_file);
 102                 }
 103         }
 104
 105         do {
 106                 const char *device;
 107                 const char *mount_point;
 108
 109                 if (mount_table) {
 110                         if (!(mount_entry = getmntent(mount_table))) {
 111                                 endmntent(mount_table);
 112                                 break;
 113                         }
 114                 } else {
 115                         if (!(mount_point = *argv++)) {
 116                                 break;
 117                         }
 118                         if (!(mount_entry = find_mount_point(mount_point, bb_path_mtab_file))) {
 119                                 bb_error_msg("%s: can't find mount point.", mount_point);
 120                         SET_ERROR:
 121                                 status = EXIT_FAILURE;
 122                                 continue;
 123                         }
 124                 }
 125
 126                 device = mount_entry->mnt_fsname;
 127                 mount_point = mount_entry->mnt_dir;
 128
 129                 if (statfs(mount_point, &s) != 0) {
 130                         bb_perror_msg("%s", mount_point);
 131                         goto SET_ERROR;
 132                 }
 133
 134                 if ((s.f_blocks > 0) || !mount_table){
 135                         blocks_used = s.f_blocks - s.f_bfree;
 136                         blocks_percent_used = 0;
 137                         if (blocks_used + s.f_bavail) {
 138                                 blocks_percent_used = (((long long) blocks_used) * 100
 139                                                                            + (blocks_used + s.f_bavail)/2
 140                                                                            ) / (blocks_used + s.f_bavail);
 141                         }
 142
 143                         if (strcmp(device, "/dev/root") == 0) {
 144                                 /* Adjusts device to be the real root device,
 145                                 * or leaves device alone if it can't find it */
 146                                 if ((device = find_real_root_device_name(device)) != NULL) {
 147                                         goto SET_ERROR;
 148                                 }
 149                         }
 150
 151 #ifdef CONFIG_FEATURE_HUMAN_READABLE
 152                         bb_printf("%-21s%9s ", device,
 153                                           make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));
 154
 155                         bb_printf("%9s ",
 156                                           make_human_readable_str( (s.f_blocks - s.f_bfree),
 157                                                                                           s.f_bsize, df_disp_hr));
 158
 159                         bb_printf("%9s %3ld%% %s\n",
 160                                           make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
 161                                           blocks_percent_used, mount_point);
 162 #else
 163                         bb_printf("%-21s%9ld %9ld %9ld %3ld%% %s\n",
 164                                           device,
 165                                           kscale(s.f_blocks, s.f_bsize),
 166                                           kscale(s.f_blocks-s.f_bfree, s.f_bsize),
 167                                           kscale(s.f_bavail, s.f_bsize),
 168                                           blocks_percent_used, mount_point);
 169 #endif
 170                 }
 171
 172         } while (1);
 173
 174         bb_fflush_stdout_and_exit(status);
 175 }
 176
 177 /*
 178 Local Variables:
 179 c-file-style: "linux"
 180 c-basic-offset: 4
 181 tab-width: 4
 182 End:
 183 */