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 /* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  11  *
  12  * Size reduction.  Removed floating point dependency.  Added error checking
  13  * on output.  Output stats on 0-sized filesystems if specifically listed on
  14  * the command line.  Properly round *-blocks, Used, and Available quantities.
  15  *
  16  * Aug 28, 2008      Bernhard Reutner-Fischer
  17  *
  18  * Implement -P and -B; better coreutils compat; cleanup
  19  */
  20 //config:config DF
  21 //config:       bool "df"
  22 //config:       default y
  23 //config:       help
  24 //config:         df reports the amount of disk space used and available
  25 //config:         on filesystems.
  26 //config:
  27 //config:config FEATURE_DF_FANCY
  28 //config:       bool "Enable -a, -i, -B"
  29 //config:       default y
  30 //config:       depends on DF
  31 //config:       help
  32 //config:         This option enables -a, -i and -B.
  33 //config:
  34 //config:           -a Show all filesystems
  35 //config:           -i Inodes
  36 //config:           -B <SIZE> Blocksize
  37
  38 //applet:IF_DF(APPLET(df, BB_DIR_BIN, BB_SUID_DROP))
  39
  40 //kbuild:lib-$(CONFIG_DF) += df.o
  41
  42 /* BB_AUDIT SUSv3 _NOT_ compliant -- option -t missing. */
  43 /* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */
  44
  45 //usage:#define df_trivial_usage
  46 //usage:        "[-Pk"
  47 //usage:        IF_FEATURE_HUMAN_READABLE("mh")
  48 //usage:        "T"
  49 //usage:        IF_FEATURE_DF_FANCY("ai] [-B SIZE")
  50 //usage:        "] [FILESYSTEM]..."
  51 //usage:#define df_full_usage "\n\n"
  52 //usage:       "Print filesystem usage statistics\n"
  53 //usage:     "\n        -P      POSIX output format"
  54 //usage:     "\n        -k      1024-byte blocks (default)"
  55 //usage:        IF_FEATURE_HUMAN_READABLE(
  56 //usage:     "\n        -m      1M-byte blocks"
  57 //usage:     "\n        -h      Human readable (e.g. 1K 243M 2G)"
  58 //usage:        )
  59 //usage:     "\n        -T      Print filesystem type"
  60 //usage:        IF_FEATURE_DF_FANCY(
  61 //usage:     "\n        -a      Show all filesystems"
  62 //usage:     "\n        -i      Inodes"
  63 //usage:     "\n        -B SIZE Blocksize"
  64 //usage:        )
  65 //usage:
  66 //usage:#define df_example_usage
  67 //usage:       "$ df\n"
  68 //usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  69 //usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  70 //usage:       "/dev/sda1                64216     36364     27852  57% /boot\n"
  71 //usage:       "$ df /dev/sda3\n"
  72 //usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  73 //usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  74 //usage:       "$ POSIXLY_CORRECT=sure df /dev/sda3\n"
  75 //usage:       "Filesystem         512B-blocks      Used Available Use% Mounted on\n"
  76 //usage:       "/dev/sda3             17381728  17107080    274648  98% /\n"
  77 //usage:       "$ POSIXLY_CORRECT=yep df -P /dev/sda3\n"
  78 //usage:       "Filesystem          512-blocks      Used Available Capacity Mounted on\n"
  79 //usage:       "/dev/sda3             17381728  17107080    274648      98% /\n"
  80
  81 #include <mntent.h>
  82 #include <sys/vfs.h>
  83 #include "libbb.h"
  84 #include "unicode.h"
  85
  86 #if !ENABLE_FEATURE_HUMAN_READABLE
  87 static unsigned long kscale(unsigned long b, unsigned long bs)
  88 {
  89         return (b * (unsigned long long) bs + 1024/2) / 1024;
  90 }
  91 #endif
  92
  93 int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  94 int df_main(int argc UNUSED_PARAM, char **argv)
  95 {
  96         unsigned long blocks_used;
  97         unsigned blocks_percent_used;
  98         unsigned long df_disp_hr = 1024;
  99         int status = EXIT_SUCCESS;
 100         unsigned opt;
 101         FILE *mount_table;
 102         struct mntent *mount_entry;
 103         struct statfs s;
 104
 105         enum {
 106                 OPT_KILO  = (1 << 0),
 107                 OPT_POSIX = (1 << 1),
 108                 OPT_FSTYPE  = (1 << 2),
 109                 OPT_ALL   = (1 << 3) * ENABLE_FEATURE_DF_FANCY,
 110                 OPT_INODE = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
 111                 OPT_BSIZE = (1 << 5) * ENABLE_FEATURE_DF_FANCY,
 112                 OPT_HUMAN = (1 << (3 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
 113                 OPT_MEGA  = (1 << (4 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
 114         };
 115         const char *disp_units_hdr = NULL;
 116         char *chp;
 117
 118         init_unicode();
 119
 120 #if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
 121         opt_complementary = "k-mB:m-Bk:B-km";
 122 #elif ENABLE_FEATURE_HUMAN_READABLE
 123         opt_complementary = "k-m:m-k";
 124 #endif
 125         opt = getopt32(argv, "kPT"
 126                         IF_FEATURE_DF_FANCY("aiB:")
 127                         IF_FEATURE_HUMAN_READABLE("hm")
 128                         IF_FEATURE_DF_FANCY(, &chp));
 129         if (opt & OPT_MEGA)
 130                 df_disp_hr = 1024*1024;
 131
 132         if (opt & OPT_BSIZE) {
 133                 /* GNU coreutils 8.25 accepts "-BMiB" form too */
 134                 int i;
 135                 for (i = 0; kmg_i_suffixes[i].suffix[0]; i++) {
 136                         if (strcmp(kmg_i_suffixes[i].suffix, chp) == 0) {
 137                                 df_disp_hr = kmg_i_suffixes[i].mult;
 138                                 goto got_it;
 139                         }
 140                 }
 141                 /* Range used to disallow 0 */
 142                 df_disp_hr = xatoul_range_sfx(chp, 1, ULONG_MAX, kmg_i_suffixes);
 143  got_it: ;
 144         }
 145
 146         /* From the manpage of df from coreutils-6.10:
 147          * Disk space is shown in 1K blocks by default, unless the environment
 148          * variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
 149          */
 150         if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
 151                 df_disp_hr = 512;
 152
 153         if (opt & OPT_HUMAN) {
 154                 df_disp_hr = 0;
 155                 disp_units_hdr = "     Size";
 156         }
 157         if (opt & OPT_INODE)
 158                 disp_units_hdr = "   Inodes";
 159
 160         if (disp_units_hdr == NULL) {
 161 #if ENABLE_FEATURE_HUMAN_READABLE
 162                 disp_units_hdr = xasprintf("%s-blocks",
 163                         /* print df_disp_hr, show no fractionals,
 164                          * use suffixes if OPT_POSIX is set in opt */
 165                         make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
 166                 );
 167 #else
 168                 disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
 169 #endif
 170         }
 171
 172         printf("Filesystem           %s%-15sUsed Available %s Mounted on\n",
 173                         (opt & OPT_FSTYPE) ? "Type       " : "",
 174                         disp_units_hdr,
 175                         (opt & OPT_POSIX) ? "Capacity" : "Use%");
 176
 177         mount_table = NULL;
 178         argv += optind;
 179         if (!argv[0]) {
 180                 mount_table = setmntent(bb_path_mtab_file, "r");
 181                 if (!mount_table)
 182                         bb_perror_msg_and_die(bb_path_mtab_file);
 183         }
 184
 185         while (1) {
 186                 const char *device;
 187                 const char *mount_point;
 188                 const char *fs_type;
 189
 190                 if (mount_table) {
 191                         mount_entry = getmntent(mount_table);
 192                         if (!mount_entry) {
 193                                 endmntent(mount_table);
 194                                 break;
 195                         }
 196                 } else {
 197                         mount_point = *argv++;
 198                         if (!mount_point)
 199                                 break;
 200                         mount_entry = find_mount_point(mount_point, 1);
 201                         if (!mount_entry) {
 202                                 bb_error_msg("%s: can't find mount point", mount_point);
 203  set_error:
 204                                 status = EXIT_FAILURE;
 205                                 continue;
 206                         }
 207                 }
 208
 209                 device = mount_entry->mnt_fsname;
 210                 mount_point = mount_entry->mnt_dir;
 211                 fs_type = mount_entry->mnt_type;
 212
 213                 if (statfs(mount_point, &s) != 0) {
 214                         bb_simple_perror_msg(mount_point);
 215                         goto set_error;
 216                 }
 217                 /* Some uclibc versions were seen to lose f_frsize
 218                  * (kernel does return it, but then uclibc does not copy it)
 219                  */
 220                 if (s.f_frsize == 0)
 221                         s.f_frsize = s.f_bsize;
 222
 223                 if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
 224                         if (opt & OPT_INODE) {
 225                                 s.f_blocks = s.f_files;
 226                                 s.f_bavail = s.f_bfree = s.f_ffree;
 227                                 s.f_frsize = 1;
 228
 229                                 if (df_disp_hr)
 230                                         df_disp_hr = 1;
 231                         }
 232                         blocks_used = s.f_blocks - s.f_bfree;
 233                         blocks_percent_used = 0;
 234                         if (blocks_used + s.f_bavail) {
 235                                 blocks_percent_used = (blocks_used * 100ULL
 236                                                 + (blocks_used + s.f_bavail)/2
 237                                                 ) / (blocks_used + s.f_bavail);
 238                         }
 239
 240                         /* GNU coreutils 6.10 skips certain mounts, try to be compatible.  */
 241                         if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(device, "rootfs") == 0)
 242                                 continue;
 243
 244 #ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
 245                         if (strcmp(device, "/dev/root") == 0) {
 246                                 /* Adjusts device to be the real root device,
 247                                  * or leaves device alone if it can't find it */
 248                                 device = find_block_device("/");
 249                                 if (!device) {
 250                                         goto set_error;
 251                                 }
 252                         }
 253 #endif
 254
 255 #if ENABLE_UNICODE_SUPPORT
 256                         {
 257                                 uni_stat_t uni_stat;
 258                                 char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
 259                                 if (uni_stat.unicode_width > 20 && !(opt & OPT_POSIX)) {
 260                                         printf("%s\n%20s", uni_dev, "");
 261                                 } else {
 262                                         printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
 263                                 }
 264                                 free(uni_dev);
 265                                 if (opt & OPT_FSTYPE) {
 266                                         char *uni_type = unicode_conv_to_printable(&uni_stat, fs_type);
 267                                         if (uni_stat.unicode_width > 10 && !(opt & OPT_POSIX))
 268                                                 printf(" %s\n%31s", uni_type, "");
 269                                         else
 270                                                 printf(" %s%*s", uni_type, 10 - (int)uni_stat.unicode_width, "");
 271                                         free(uni_type);
 272                                 }
 273                         }
 274 #else
 275                         if (printf("\n%-20s" + 1, device) > 20 && !(opt & OPT_POSIX))
 276                                 printf("\n%-20s", "");
 277                         if (opt & OPT_FSTYPE) {
 278                                 if (printf(" %-10s", fs_type) > 11 && !(opt & OPT_POSIX))
 279                                         printf("\n%-30s", "");
 280                         }
 281 #endif
 282
 283 #if ENABLE_FEATURE_HUMAN_READABLE
 284                         printf(" %9s ",
 285                                 /* f_blocks x f_frsize / df_disp_hr, show one fractional,
 286                                  * use suffixes if df_disp_hr == 0 */
 287                                 make_human_readable_str(s.f_blocks, s.f_frsize, df_disp_hr));
 288
 289                         printf(" %9s " + 1,
 290                                 /* EXPR x f_frsize / df_disp_hr, show one fractional,
 291                                  * use suffixes if df_disp_hr == 0 */
 292                                 make_human_readable_str((s.f_blocks - s.f_bfree),
 293                                                 s.f_frsize, df_disp_hr));
 294
 295                         printf("%9s %3u%% %s\n",
 296                                 /* f_bavail x f_frsize / df_disp_hr, show one fractional,
 297                                  * use suffixes if df_disp_hr == 0 */
 298                                 make_human_readable_str(s.f_bavail, s.f_frsize, df_disp_hr),
 299                                 blocks_percent_used, mount_point);
 300 #else
 301                         printf(" %9lu %9lu %9lu %3u%% %s\n",
 302                                 kscale(s.f_blocks, s.f_frsize),
 303                                 kscale(s.f_blocks - s.f_bfree, s.f_frsize),
 304                                 kscale(s.f_bavail, s.f_frsize),
 305                                 blocks_percent_used, mount_point);
 306 #endif
 307                 }
 308         }
 309
 310         return status;
 311 }