coreutils/df.c

   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
  26 static unsigned long kscale(unsigned long b, unsigned long bs)
  27 {
  28         return (b * (unsigned long long) bs + 1024/2) / 1024;
  29 }
  30 #endif
  31
  32 int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  33 int 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         enum {
  49                 OPT_INODE = (ENABLE_FEATURE_HUMAN_READABLE ? (1 << 3) : (1 << 1))
  50                             * ENABLE_FEATURE_DF_INODE
  51         };
  52
  53 #if ENABLE_FEATURE_HUMAN_READABLE
  54         opt_complementary = "h-km:k-hm:m-hk";
  55         opt = getopt32(argv, "hmk" USE_FEATURE_DF_INODE("i"));
  56         if (opt & 1) {
  57                 df_disp_hr = 0;
  58                 disp_units_hdr = "     Size";
  59         }
  60         if (opt & 2) {
  61                 df_disp_hr = 1024*1024;
  62                 disp_units_hdr = "1M-blocks";
  63         }
  64         if (opt & OPT_INODE) {
  65                 disp_units_hdr = "   Inodes";
  66         }
  67 #else
  68         opt = getopt32(argv, "k" USE_FEATURE_DF_INODE("i"));
  69 #endif
  70
  71         printf("Filesystem%11s%-15sUsed Available Use%% Mounted on\n",
  72                           "", disp_units_hdr);
  73
  74         mount_table = NULL;
  75         argv += optind;
  76         if (optind >= argc) {
  77                 mount_table = setmntent(bb_path_mtab_file, "r");
  78                 if (!mount_table) {
  79                         bb_perror_msg_and_die(bb_path_mtab_file);
  80                 }
  81         }
  82
  83         while (1) {
  84                 const char *device;
  85                 const char *mount_point;
  86
  87                 if (mount_table) {
  88                         mount_entry = getmntent(mount_table);
  89                         if (!mount_entry) {
  90                                 endmntent(mount_table);
  91                                 break;
  92                         }
  93                 } else {
  94                         mount_point = *argv++;
  95                         if (!mount_point) {
  96                                 break;
  97                         }
  98                         mount_entry = find_mount_point(mount_point, bb_path_mtab_file);
  99                         if (!mount_entry) {
 100                                 bb_error_msg("%s: can't find mount point", mount_point);
 101  SET_ERROR:
 102                                 status = EXIT_FAILURE;
 103                                 continue;
 104                         }
 105                 }
 106
 107                 device = mount_entry->mnt_fsname;
 108                 mount_point = mount_entry->mnt_dir;
 109
 110                 if (statfs(mount_point, &s) != 0) {
 111                         bb_simple_perror_msg(mount_point);
 112                         goto SET_ERROR;
 113                 }
 114
 115                 if ((s.f_blocks > 0) || !mount_table) {
 116                         if (opt & OPT_INODE) {
 117                                 s.f_blocks = s.f_files;
 118                                 s.f_bavail = s.f_bfree = s.f_ffree;
 119                                 s.f_bsize = 1;
 120 #if ENABLE_FEATURE_HUMAN_READABLE
 121                                 if (df_disp_hr)
 122                                         df_disp_hr = 1;
 123 #endif
 124                         }
 125                         blocks_used = s.f_blocks - s.f_bfree;
 126                         blocks_percent_used = 0;
 127                         if (blocks_used + s.f_bavail) {
 128                                 blocks_percent_used = (blocks_used * 100ULL
 129                                                 + (blocks_used + s.f_bavail)/2
 130                                                 ) / (blocks_used + s.f_bavail);
 131                         }
 132
 133                         if (strcmp(device, "rootfs") == 0) {
 134                                 continue;
 135                         }
 136                         if (strcmp(device, "/dev/root") == 0) {
 137                                 /* Adjusts device to be the real root device,
 138                                 * or leaves device alone if it can't find it */
 139                                 device = find_block_device("/");
 140                                 if (!device) {
 141                                         goto SET_ERROR;
 142                                 }
 143                         }
 144
 145                         if (printf("\n%-20s" + 1, device) > 20)
 146                                     printf("\n%-20s", "");
 147 #if ENABLE_FEATURE_HUMAN_READABLE
 148                         printf(" %9s ",
 149                                 make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));
 150
 151                         printf(" %9s " + 1,
 152                                 make_human_readable_str((s.f_blocks - s.f_bfree),
 153                                                 s.f_bsize, df_disp_hr));
 154
 155                         printf("%9s %3u%% %s\n",
 156                                         make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
 157                                         blocks_percent_used, mount_point);
 158 #else
 159                         printf(" %9lu %9lu %9lu %3u%% %s\n",
 160                                         kscale(s.f_blocks, s.f_bsize),
 161                                         kscale(s.f_blocks-s.f_bfree, s.f_bsize),
 162                                         kscale(s.f_bavail, s.f_bsize),
 163                                         blocks_percent_used, mount_point);
 164 #endif
 165                 }
 166         }
 167
 168         fflush_stdout_and_exit(status);
 169 }