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 source tree.
   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 //usage:#define df_trivial_usage
  26 //usage:        "[-Pk"
  27 //usage:        IF_FEATURE_HUMAN_READABLE("mh")
  28 //usage:        "T"
  29 //usage:        IF_FEATURE_DF_FANCY("ai] [-B SIZE")
  30 //usage:        "] [FILESYSTEM]..."
  31 //usage:#define df_full_usage "\n\n"
  32 //usage:       "Print filesystem usage statistics\n"
  33 //usage:     "\n        -P      POSIX output format"
  34 //usage:     "\n        -k      1024-byte blocks (default)"
  35 //usage:        IF_FEATURE_HUMAN_READABLE(
  36 //usage:     "\n        -m      1M-byte blocks"
  37 //usage:     "\n        -h      Human readable (e.g. 1K 243M 2G)"
  38 //usage:        )
  39 //usage:     "\n        -T      Print filesystem type"
  40 //usage:        IF_FEATURE_DF_FANCY(
  41 //usage:     "\n        -a      Show all filesystems"
  42 //usage:     "\n        -i      Inodes"
  43 //usage:     "\n        -B SIZE Blocksize"
  44 //usage:        )
  45 //usage:
  46 //usage:#define df_example_usage
  47 //usage:       "$ df\n"
  48 //usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  49 //usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  50 //usage:       "/dev/sda1                64216     36364     27852  57% /boot\n"
  51 //usage:       "$ df /dev/sda3\n"
  52 //usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  53 //usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  54 //usage:       "$ POSIXLY_CORRECT=sure df /dev/sda3\n"
  55 //usage:       "Filesystem         512B-blocks      Used Available Use% Mounted on\n"
  56 //usage:       "/dev/sda3             17381728  17107080    274648  98% /\n"
  57 //usage:       "$ POSIXLY_CORRECT=yep df -P /dev/sda3\n"
  58 //usage:       "Filesystem          512-blocks      Used Available Capacity Mounted on\n"
  59 //usage:       "/dev/sda3             17381728  17107080    274648      98% /\n"
  60
  61 #include <mntent.h>
  62 #include <sys/vfs.h>
  63 #include "libbb.h"
  64 #include "unicode.h"
  65
  66 #if !ENABLE_FEATURE_HUMAN_READABLE
  67 static unsigned long kscale(unsigned long b, unsigned long bs)
  68 {
  69         return (b * (unsigned long long) bs + 1024/2) / 1024;
  70 }
  71 #endif
  72
  73 int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  74 int df_main(int argc UNUSED_PARAM, char **argv)
  75 {
  76         unsigned long blocks_used;
  77         unsigned blocks_percent_used;
  78         unsigned long df_disp_hr = 1024;
  79         int status = EXIT_SUCCESS;
  80         unsigned opt;
  81         FILE *mount_table;
  82         struct mntent *mount_entry;
  83         struct statfs s;
  84
  85         enum {
  86                 OPT_KILO  = (1 << 0),
  87                 OPT_POSIX = (1 << 1),
  88                 OPT_FSTYPE  = (1 << 2),
  89                 OPT_ALL   = (1 << 3) * ENABLE_FEATURE_DF_FANCY,
  90                 OPT_INODE = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
  91                 OPT_BSIZE = (1 << 5) * ENABLE_FEATURE_DF_FANCY,
  92                 OPT_HUMAN = (1 << (3 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
  93                 OPT_MEGA  = (1 << (4 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
  94         };
  95         const char *disp_units_hdr = NULL;
  96         char *chp;
  97
  98         init_unicode();
  99
 100 #if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
 101         opt_complementary = "k-mB:m-Bk:B-km";
 102 #elif ENABLE_FEATURE_HUMAN_READABLE
 103         opt_complementary = "k-m:m-k";
 104 #endif
 105         opt = getopt32(argv, "kPT"
 106                         IF_FEATURE_DF_FANCY("aiB:")
 107                         IF_FEATURE_HUMAN_READABLE("hm")
 108                         IF_FEATURE_DF_FANCY(, &chp));
 109         if (opt & OPT_MEGA)
 110                 df_disp_hr = 1024*1024;
 111
 112         if (opt & OPT_BSIZE)
 113                 df_disp_hr = xatoul_range(chp, 1, ULONG_MAX); /* disallow 0 */
 114
 115         /* From the manpage of df from coreutils-6.10:
 116          * Disk space is shown in 1K blocks by default, unless the environment
 117          * variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
 118          */
 119         if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
 120                 df_disp_hr = 512;
 121
 122         if (opt & OPT_HUMAN) {
 123                 df_disp_hr = 0;
 124                 disp_units_hdr = "     Size";
 125         }
 126         if (opt & OPT_INODE)
 127                 disp_units_hdr = "   Inodes";
 128
 129         if (disp_units_hdr == NULL) {
 130 #if ENABLE_FEATURE_HUMAN_READABLE
 131                 disp_units_hdr = xasprintf("%s-blocks",
 132                         /* print df_disp_hr, show no fractionals,
 133                          * use suffixes if OPT_POSIX is set in opt */
 134                         make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
 135                 );
 136 #else
 137                 disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
 138 #endif
 139         }
 140
 141         printf("Filesystem           %s%-15sUsed Available %s Mounted on\n",
 142                         (opt & OPT_FSTYPE) ? "Type       " : "",
 143                         disp_units_hdr,
 144                         (opt & OPT_POSIX) ? "Capacity" : "Use%");
 145
 146         mount_table = NULL;
 147         argv += optind;
 148         if (!argv[0]) {
 149                 mount_table = setmntent(bb_path_mtab_file, "r");
 150                 if (!mount_table)
 151                         bb_perror_msg_and_die(bb_path_mtab_file);
 152         }
 153
 154         while (1) {
 155                 const char *device;
 156                 const char *mount_point;
 157                 const char *fs_type;
 158
 159                 if (mount_table) {
 160                         mount_entry = getmntent(mount_table);
 161                         if (!mount_entry) {
 162                                 endmntent(mount_table);
 163                                 break;
 164                         }
 165                 } else {
 166                         mount_point = *argv++;
 167                         if (!mount_point)
 168                                 break;
 169                         mount_entry = find_mount_point(mount_point, 1);
 170                         if (!mount_entry) {
 171                                 bb_error_msg("%s: can't find mount point", mount_point);
 172  set_error:
 173                                 status = EXIT_FAILURE;
 174                                 continue;
 175                         }
 176                 }
 177
 178                 device = mount_entry->mnt_fsname;
 179                 mount_point = mount_entry->mnt_dir;
 180                 fs_type = mount_entry->mnt_type;
 181
 182                 if (statfs(mount_point, &s) != 0) {
 183                         bb_simple_perror_msg(mount_point);
 184                         goto set_error;
 185                 }
 186
 187                 if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
 188                         if (opt & OPT_INODE) {
 189                                 s.f_blocks = s.f_files;
 190                                 s.f_bavail = s.f_bfree = s.f_ffree;
 191                                 s.f_frsize = 1;
 192
 193                                 if (df_disp_hr)
 194                                         df_disp_hr = 1;
 195                         }
 196                         blocks_used = s.f_blocks - s.f_bfree;
 197                         blocks_percent_used = 0;
 198                         if (blocks_used + s.f_bavail) {
 199                                 blocks_percent_used = (blocks_used * 100ULL
 200                                                 + (blocks_used + s.f_bavail)/2
 201                                                 ) / (blocks_used + s.f_bavail);
 202                         }
 203
 204                         /* GNU coreutils 6.10 skips certain mounts, try to be compatible.  */
 205                         if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(device, "rootfs") == 0)
 206                                 continue;
 207
 208 #ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
 209                         if (strcmp(device, "/dev/root") == 0) {
 210                                 /* Adjusts device to be the real root device,
 211                                  * or leaves device alone if it can't find it */
 212                                 device = find_block_device("/");
 213                                 if (!device) {
 214                                         goto set_error;
 215                                 }
 216                         }
 217 #endif
 218
 219 #if ENABLE_UNICODE_SUPPORT
 220                         {
 221                                 uni_stat_t uni_stat;
 222                                 char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
 223                                 if (uni_stat.unicode_width > 20 && !(opt & OPT_POSIX)) {
 224                                         printf("%s\n%20s", uni_dev, "");
 225                                 } else {
 226                                         printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
 227                                 }
 228                                 free(uni_dev);
 229                                 if (opt & OPT_FSTYPE) {
 230                                         char *uni_type = unicode_conv_to_printable(&uni_stat, fs_type);
 231                                         if (uni_stat.unicode_width > 10 && !(opt & OPT_POSIX))
 232                                                 printf(" %s\n%31s", uni_type, "");
 233                                         else
 234                                                 printf(" %s%*s", uni_type, 10 - (int)uni_stat.unicode_width, "");
 235                                         free(uni_type);
 236                                 }
 237                         }
 238 #else
 239                         if (printf("\n%-20s" + 1, device) > 20 && !(opt & OPT_POSIX))
 240                                 printf("\n%-20s", "");
 241                         if (opt & OPT_FSTYPE) {
 242                                 if (printf(" %-10s", fs_type) > 11 && !(opt & OPT_POSIX))
 243                                         printf("\n%-30s", "");
 244                         }
 245 #endif
 246
 247 #if ENABLE_FEATURE_HUMAN_READABLE
 248                         printf(" %9s ",
 249                                 /* f_blocks x f_frsize / df_disp_hr, show one fractional,
 250                                  * use suffixes if df_disp_hr == 0 */
 251                                 make_human_readable_str(s.f_blocks, s.f_frsize, df_disp_hr));
 252
 253                         printf(" %9s " + 1,
 254                                 /* EXPR x f_frsize / df_disp_hr, show one fractional,
 255                                  * use suffixes if df_disp_hr == 0 */
 256                                 make_human_readable_str((s.f_blocks - s.f_bfree),
 257                                                 s.f_frsize, df_disp_hr));
 258
 259                         printf("%9s %3u%% %s\n",
 260                                 /* f_bavail x f_frsize / df_disp_hr, show one fractional,
 261                                  * use suffixes if df_disp_hr == 0 */
 262                                 make_human_readable_str(s.f_bavail, s.f_frsize, df_disp_hr),
 263                                 blocks_percent_used, mount_point);
 264 #else
 265                         printf(" %9lu %9lu %9lu %3u%% %s\n",
 266                                 kscale(s.f_blocks, s.f_frsize),
 267                                 kscale(s.f_blocks - s.f_bfree, s.f_frsize),
 268                                 kscale(s.f_bavail, s.f_frsize),
 269                                 blocks_percent_used, mount_point);
 270 #endif
 271                 }
 272         }
 273
 274         return status;
 275 }