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