src/df.c

   1 /* df - summarize free disk space
   2    Copyright (C) 91, 95, 1996 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.
  19    --human-readable and --megabyte options added by lm@sgi.com.  */
  20
  21 #include <config.h>
  22 #include <stdio.h>
  23 #include <sys/types.h>
  24 #include <getopt.h>
  25 #include <assert.h>
  26
  27 #include "mountlist.h"
  28 #include "fsusage.h"
  29 #include "system.h"
  30 #include "error.h"
  31
  32 char *xmalloc ();
  33 char *xstrdup ();
  34
  35 /* The maximum length of a human-readable string.  Be pessimistic
  36    and assume `int' is 64-bits wide.  Converting 2^63 - 1 gives the
  37    14-character string, 8796093022208G.  The number being converted
  38    is the number of 1024-byte blocks, so we divide by 1024 * 1024.  */
  39 #define LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS 14
  40
  41 /* Name this program was run with. */
  42 char *program_name;
  43
  44 /* If nonzero, show inode information. */
  45 static int inode_format;
  46
  47 /* If nonzero, show even filesystems with zero size or
  48    uninteresting types. */
  49 static int show_all_fs;
  50
  51 /* If nonzero, output data for each filesystem corresponding to a
  52    command line argument -- even if it's a dummy (automounter) entry.  */
  53 static int show_listed_fs;
  54
  55 /* If nonzero, use variable sized printouts instead of 512-byte blocks. */
  56 static int human_blocks;
  57
  58 /* If nonzero, use 1K blocks instead of 512-byte blocks. */
  59 static int kilobyte_blocks;
  60
  61 /* If nonzero, use 1M blocks instead of 512-byte blocks. */
  62 static int megabyte_blocks;
  63
  64 /* If nonzero, use the POSIX output format.  */
  65 static int posix_format;
  66
  67 /* If nonzero, invoke the `sync' system call before getting any usage data.
  68    Using this option can make df very slow, especially with many or very
  69    busy disks.  Note that this may make a difference on some systems --
  70    SunOs4.1.3, for one.  It is *not* necessary on Linux.  */
  71 static int require_sync = 0;
  72
  73 /* Nonzero if errors have occurred. */
  74 static int exit_status;
  75
  76 /* A filesystem type to display. */
  77
  78 struct fs_type_list
  79 {
  80   char *fs_name;
  81   struct fs_type_list *fs_next;
  82 };
  83
  84 /* Linked list of filesystem types to display.
  85    If `fs_select_list' is NULL, list all types.
  86    This table is generated dynamically from command-line options,
  87    rather than hardcoding into the program what it thinks are the
  88    valid filesystem types; let the user specify any filesystem type
  89    they want to, and if there are any filesystems of that type, they
  90    will be shown.
  91
  92    Some filesystem types:
  93    4.2 4.3 ufs nfs swap ignore io vm efs dbg */
  94
  95 static struct fs_type_list *fs_select_list;
  96
  97 /* Linked list of filesystem types to omit.
  98    If the list is empty, don't exclude any types.  */
  99
 100 static struct fs_type_list *fs_exclude_list;
 101
 102 /* Linked list of mounted filesystems. */
 103 static struct mount_entry *mount_list;
 104
 105 /* If nonzero, display usage information and exit.  */
 106 static int show_help;
 107
 108 /* If nonzero, print the version on standard output and exit.  */
 109 static int show_version;
 110
 111 /* If nonzero, print filesystem type as well.  */
 112 static int print_type;
 113
 114 static struct option const long_options[] =
 115 {
 116   {"all", no_argument, &show_all_fs, 1},
 117   {"inodes", no_argument, &inode_format, 1},
 118   {"human-readable", no_argument, 0, 'h'},
 119   {"kilobytes", no_argument, 0, 'k'},
 120   {"megabytes", no_argument, 0, 'm'},
 121   {"portability", no_argument, &posix_format, 1},
 122   {"print-type", no_argument, &print_type, 1},
 123   {"sync", no_argument, 0, 129},
 124   {"no-sync", no_argument, 0, 130},
 125   {"type", required_argument, 0, 't'},
 126   {"exclude-type", required_argument, 0, 'x'},
 127   {"help", no_argument, &show_help, 1},
 128   {"version", no_argument, &show_version, 1},
 129   {NULL, 0, NULL, 0}
 130 };
 131
 132 static void
 133 print_header (void)
 134 {
 135   printf ("Filesystem ");
 136
 137   if (print_type)
 138     printf ("   Type");
 139   else
 140     printf ("       ");
 141
 142   if (inode_format)
 143     printf ("   Inodes   IUsed   IFree  %%IUsed");
 144   else
 145     if (megabyte_blocks)
 146       printf (" MB-blocks    Used Available Capacity");
 147     else if (human_blocks)
 148       printf ("    Size  Used  Avail  Capacity");
 149     else
 150       printf (" %s  Used Available Capacity",
 151             kilobyte_blocks ? "1024-blocks" : " 512-blocks");
 152   printf (" Mounted on\n");
 153 }
 154
 155 /* Convert N_1K_BYTE_BLOCKS to a more readable string than %d would.
 156    Most people visually process strings of 3-4 digits effectively,
 157    but longer strings of digits are more prone to misinterpretation.
 158    Hence, converting to an abbreviated form usually improves readability.
 159    Use a suffix indicating multiples of 1024 (M) and 1024*1024 (G).
 160    For example, 8500 would be converted to 8.3M, 133456345 to 127G,
 161    and so on.  Numbers smaller than 1024 get the `K' suffix.  */
 162
 163 static char *
 164 human_readable_1k_blocks (int n_1k_byte_blocks, char *buf, int buf_len)
 165 {
 166   const char *suffix;
 167   double amt;
 168   char *p;
 169
 170   assert (buf_len > LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS);
 171
 172   p = buf;
 173   amt = n_1k_byte_blocks;
 174
 175   if (amt >= 1024 * 1024)
 176     {
 177       amt /= (1024 * 1024);
 178       suffix = "G";
 179     }
 180   else if (amt >= 1024)
 181     {
 182       amt /= 1024;
 183       suffix = "M";
 184     }
 185   else
 186     {
 187       suffix = "K";
 188     }
 189
 190   if (amt >= 10)
 191     {
 192       sprintf (p, "%4.0f%s", amt, suffix);
 193     }
 194   else if (amt == 0)
 195     {
 196       strcpy (p, "0");
 197     }
 198   else
 199     {
 200       sprintf (p, "%4.1f%s", amt, suffix);
 201     }
 202   return (p);
 203 }
 204
 205 /* If FSTYPE is a type of filesystem that should be listed,
 206    return nonzero, else zero. */
 207
 208 static int
 209 selected_fstype (const char *fstype)
 210 {
 211   const struct fs_type_list *fsp;
 212
 213   if (fs_select_list == NULL || fstype == NULL)
 214     return 1;
 215   for (fsp = fs_select_list; fsp; fsp = fsp->fs_next)
 216     if (STREQ (fstype, fsp->fs_name))
 217       return 1;
 218   return 0;
 219 }
 220
 221 /* If FSTYPE is a type of filesystem that should be omitted,
 222    return nonzero, else zero. */
 223
 224 static int
 225 excluded_fstype (const char *fstype)
 226 {
 227   const struct fs_type_list *fsp;
 228
 229   if (fs_exclude_list == NULL || fstype == NULL)
 230     return 0;
 231   for (fsp = fs_exclude_list; fsp; fsp = fsp->fs_next)
 232     if (STREQ (fstype, fsp->fs_name))
 233       return 1;
 234   return 0;
 235 }
 236
 237 /* Display a space listing for the disk device with absolute path DISK.
 238    If MOUNT_POINT is non-NULL, it is the path of the root of the
 239    filesystem on DISK.
 240    If FSTYPE is non-NULL, it is the type of the filesystem on DISK. */
 241
 242 static void
 243 show_dev (const char *disk, const char *mount_point, const char *fstype)
 244 {
 245   struct fs_usage fsu;
 246   long blocks_used;
 247   long blocks_percent_used;
 248   long inodes_used;
 249   long inodes_percent_used;
 250   const char *stat_file;
 251
 252   if (!selected_fstype (fstype) || excluded_fstype (fstype))
 253     return;
 254
 255   /* If MOUNT_POINT is NULL, then the filesystem is not mounted, and this
 256      program reports on the filesystem that the special file is on.
 257      It would be better to report on the unmounted filesystem,
 258      but statfs doesn't do that on most systems.  */
 259   stat_file = mount_point ? mount_point : disk;
 260
 261   if (get_fs_usage (stat_file, disk, &fsu))
 262     {
 263       error (0, errno, "%s", stat_file);
 264       exit_status = 1;
 265       return;
 266     }
 267
 268   if (megabyte_blocks)
 269     {
 270       fsu.fsu_blocks /= 2*1024;
 271       fsu.fsu_bfree /= 2*1024;
 272       fsu.fsu_bavail /= 2*1024;
 273     }
 274   else if (kilobyte_blocks)
 275     {
 276       fsu.fsu_blocks /= 2;
 277       fsu.fsu_bfree /= 2;
 278       fsu.fsu_bavail /= 2;
 279     }
 280
 281   if (fsu.fsu_blocks == 0)
 282     {
 283       if (!show_all_fs && !show_listed_fs)
 284         return;
 285       blocks_used = fsu.fsu_bavail = blocks_percent_used = 0;
 286     }
 287   else
 288     {
 289       blocks_used = fsu.fsu_blocks - fsu.fsu_bfree;
 290       blocks_percent_used = (long)
 291         (blocks_used * 100.0 / (blocks_used + fsu.fsu_bavail) + 0.5);
 292     }
 293
 294   if (fsu.fsu_files == 0)
 295     {
 296       inodes_used = fsu.fsu_ffree = inodes_percent_used = 0;
 297     }
 298   else
 299     {
 300       inodes_used = fsu.fsu_files - fsu.fsu_ffree;
 301       inodes_percent_used = (long)
 302         (inodes_used * 100.0 / fsu.fsu_files + 0.5);
 303     }
 304
 305   printf ((print_type ? "%-13s" : "%-20s"), disk);
 306   if (strlen (disk) > (print_type ? 13 : 20) && !posix_format)
 307     printf ((print_type ? "\n%13s" : "\n%20s"), "");
 308
 309   if (print_type)
 310     printf (" %-5s ", fstype);
 311
 312   if (inode_format)
 313     printf (" %7ld %7ld %7ld %5ld%%",
 314             fsu.fsu_files, inodes_used, fsu.fsu_ffree, inodes_percent_used);
 315   else if (human_blocks)
 316     {
 317       char buf[3][LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS + 1];
 318       printf (" %4s %4s  %5s  %5ld%% ",
 319               human_readable_1k_blocks (fsu.fsu_blocks, buf[0],
 320                                     LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS + 1),
 321               human_readable_1k_blocks (blocks_used, buf[1],
 322                                     LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS + 1),
 323               human_readable_1k_blocks (fsu.fsu_bavail, buf[2],
 324                                     LONGEST_HUMAN_READABLE_1K_BYTE_BLOCKS + 1),
 325               blocks_percent_used);
 326     }
 327   else
 328     printf (" %7ld %7ld  %7ld  %5ld%% ",
 329             fsu.fsu_blocks, blocks_used, fsu.fsu_bavail, blocks_percent_used);
 330
 331   if (mount_point)
 332     {
 333 #ifdef HIDE_AUTOMOUNT_PREFIX
 334       /* Don't print the first directory name in MOUNT_POINT if it's an
 335          artifact of an automounter.  This is a bit too aggressive to be
 336          the default.  */
 337       if (strncmp ("/auto/", mount_point, 6) == 0)
 338         mount_point += 5;
 339       else if (strncmp ("/tmp_mnt/", mount_point, 9) == 0)
 340         mount_point += 8;
 341 #endif
 342       printf ("  %s", mount_point);
 343     }
 344   putchar ('\n');
 345 }
 346
 347 /* Identify the directory, if any, that device
 348    DISK is mounted on, and show its disk usage.  */
 349
 350 static void
 351 show_disk (const char *disk)
 352 {
 353   struct mount_entry *me;
 354
 355   for (me = mount_list; me; me = me->me_next)
 356     if (STREQ (disk, me->me_devname))
 357       {
 358         show_dev (me->me_devname, me->me_mountdir, me->me_type);
 359         return;
 360       }
 361   /* No filesystem is mounted on DISK. */
 362   show_dev (disk, (char *) NULL, (char *) NULL);
 363 }
 364
 365 /* Figure out which device file or directory POINT is mounted on
 366    and show its disk usage.
 367    STATP is the results of `stat' on POINT.  */
 368
 369 static void
 370 show_point (const char *point, const struct stat *statp)
 371 {
 372   struct stat disk_stats;
 373   struct mount_entry *me;
 374
 375   for (me = mount_list; me; me = me->me_next)
 376     {
 377       if (me->me_dev == (dev_t) -1)
 378         {
 379           if (stat (me->me_mountdir, &disk_stats) == 0)
 380             me->me_dev = disk_stats.st_dev;
 381           else
 382             {
 383               error (0, errno, "%s", me->me_mountdir);
 384               exit_status = 1;
 385               /* So we won't try and fail repeatedly. */
 386               me->me_dev = (dev_t) -2;
 387             }
 388         }
 389
 390       if (statp->st_dev == me->me_dev)
 391         {
 392           /* Skip bogus mtab entries.  */
 393           if (stat (me->me_mountdir, &disk_stats) != 0 ||
 394               disk_stats.st_dev != me->me_dev)
 395             continue;
 396           show_dev (me->me_devname, me->me_mountdir, me->me_type);
 397           return;
 398         }
 399     }
 400   error (0, 0, _("cannot find mount point for %s"), point);
 401   exit_status = 1;
 402 }
 403
 404 /* Determine what kind of node PATH is and show the disk usage
 405    for it.  STATP is the results of `stat' on PATH.  */
 406
 407 static void
 408 show_entry (const char *path, const struct stat *statp)
 409 {
 410   if (S_ISBLK (statp->st_mode) || S_ISCHR (statp->st_mode))
 411     show_disk (path);
 412   else
 413     show_point (path, statp);
 414 }
 415
 416 /* Show all mounted filesystems, except perhaps those that are of
 417    an unselected type or are empty. */
 418
 419 static void
 420 show_all_entries (void)
 421 {
 422   struct mount_entry *me;
 423
 424   for (me = mount_list; me; me = me->me_next)
 425     show_dev (me->me_devname, me->me_mountdir, me->me_type);
 426 }
 427
 428 /* Add FSTYPE to the list of filesystem types to display. */
 429
 430 static void
 431 add_fs_type (const char *fstype)
 432 {
 433   struct fs_type_list *fsp;
 434
 435   fsp = (struct fs_type_list *) xmalloc (sizeof (struct fs_type_list));
 436   fsp->fs_name = (char *) fstype;
 437   fsp->fs_next = fs_select_list;
 438   fs_select_list = fsp;
 439 }
 440
 441 /* Add FSTYPE to the list of filesystem types to be omitted. */
 442
 443 static void
 444 add_excluded_fs_type (const char *fstype)
 445 {
 446   struct fs_type_list *fsp;
 447
 448   fsp = (struct fs_type_list *) xmalloc (sizeof (struct fs_type_list));
 449   fsp->fs_name = (char *) fstype;
 450   fsp->fs_next = fs_exclude_list;
 451   fs_exclude_list = fsp;
 452 }
 453
 454 static void
 455 usage (int status)
 456 {
 457   if (status != 0)
 458     fprintf (stderr, _("Try `%s --help' for more information.\n"),
 459              program_name);
 460   else
 461     {
 462       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
 463       printf (_("\
 464 Show information about the filesystem on which each FILE resides,\n\
 465 or all filesystems by default.\n\
 466 \n\
 467   -a, --all             include filesystems having 0 blocks\n\
 468   -h, --human-readable  print sizes in human readable format (e.g. 1K 234M 2G)\n\
 469   -i, --inodes          list inode information instead of block usage\n\
 470   -k, --kilobytes       use 1024-byte blocks, not 512 despite POSIXLY_CORRECT\n\
 471   -m, --megabytes       use 1024K-byte blocks, not 512 despite POSIXLY_CORRECT\n\
 472       --no-sync         do not invoke sync before getting usage info (default)\n\
 473       --sync            invoke sync before getting usage info\n\
 474   -t, --type=TYPE       limit listing to filesystems of type TYPE\n\
 475   -x, --exclude-type=TYPE   limit listing to filesystems not of type TYPE\n\
 476   -v                    (ignored)\n\
 477   -P, --portability     use the POSIX output format\n\
 478   -T, --print-type      print filesystem type\n\
 479       --help            display this help and exit\n\
 480       --version         output version information and exit\n"));
 481     }
 482   exit (status);
 483 }
 484
 485 int
 486 main (int argc, char **argv)
 487 {
 488   int i;
 489   struct stat *stats;
 490
 491   program_name = argv[0];
 492   setlocale (LC_ALL, "");
 493   bindtextdomain (PACKAGE, LOCALEDIR);
 494   textdomain (PACKAGE);
 495
 496   fs_select_list = NULL;
 497   fs_exclude_list = NULL;
 498   inode_format = 0;
 499   show_all_fs = 0;
 500   show_listed_fs = 0;
 501
 502   if (getenv ("POSIXLY_CORRECT"))
 503     kilobyte_blocks = 0;
 504   else
 505     {
 506       char *bs;
 507       kilobyte_blocks = 1;
 508       if ((bs = getenv ("BLOCKSIZE"))
 509           && strncmp (bs, "HUMAN", sizeof ("HUMAN") - 1) == 0)
 510         human_blocks = 1;
 511     }
 512
 513   print_type = 0;
 514   posix_format = 0;
 515   exit_status = 0;
 516
 517   while ((i = getopt_long (argc, argv, "aihkmPTt:vx:", long_options, NULL))
 518          != EOF)
 519     {
 520       switch (i)
 521         {
 522         case 0:                 /* Long option. */
 523           break;
 524         case 'a':
 525           show_all_fs = 1;
 526           break;
 527         case 'i':
 528           inode_format = 1;
 529           break;
 530         case 'h':
 531           human_blocks = 1;
 532           kilobyte_blocks = 1;
 533           megabyte_blocks = 0;
 534           break;
 535         case 'k':
 536           human_blocks = 0;
 537           kilobyte_blocks = 1;
 538           megabyte_blocks = 0;
 539           break;
 540         case 'm':
 541           human_blocks = 0;
 542           kilobyte_blocks = 0;
 543           megabyte_blocks = 1;
 544           break;
 545         case 'T':
 546           print_type = 1;
 547           break;
 548         case 'P':
 549           posix_format = 1;
 550           break;
 551         case 129:
 552           require_sync = 1;
 553           break;
 554         case 130:
 555           require_sync = 0;
 556           break;
 557         case 't':
 558           add_fs_type (optarg);
 559           break;
 560         case 'v':               /* For SysV compatibility. */
 561           /* ignore */
 562           break;
 563         case 'x':
 564           add_excluded_fs_type (optarg);
 565           break;
 566         default:
 567           usage (1);
 568         }
 569     }
 570
 571   if (show_version)
 572     {
 573       printf ("df - %s\n", PACKAGE_VERSION);
 574       exit (0);
 575     }
 576
 577   if (show_help)
 578     usage (0);
 579
 580   if (posix_format && megabyte_blocks)
 581     error (1, 0, _("the option for counting 1MB blocks may not be used\n\
 582 with the portable output format"));
 583
 584   if (posix_format && human_blocks)
 585     error (1, 0,
 586            _("the option for printing with adaptive units may not be used\n\
 587 with the portable output format"));
 588
 589   /* Fail if the same file system type was both selected and excluded.  */
 590   {
 591     int match = 0;
 592     struct fs_type_list *i;
 593     for (i = fs_select_list; i; i = i->fs_next)
 594       {
 595         struct fs_type_list *j;
 596         for (j = fs_exclude_list; j; j = j->fs_next)
 597           {
 598             if (STREQ (i->fs_name, j->fs_name))
 599               {
 600                 error (0, 0,
 601                        _("file system type `%s' both selected and excluded"),
 602                        i->fs_name);
 603                 match = 1;
 604                 break;
 605               }
 606           }
 607       }
 608     if (match)
 609       exit (1);
 610   }
 611
 612   if (optind == argc)
 613     {
 614 #ifdef lint
 615       /* Suppress `used before initialized' warning.  */
 616       stats = NULL;
 617 #endif
 618     }
 619   else
 620     {
 621       /* stat all the given entries to make sure they get automounted,
 622          if necessary, before reading the filesystem table.  */
 623       stats = (struct stat *)
 624         xmalloc ((argc - optind) * sizeof (struct stat));
 625       for (i = optind; i < argc; ++i)
 626         if (stat (argv[i], &stats[i - optind]))
 627           {
 628             error (0, errno, "%s", argv[i]);
 629             exit_status = 1;
 630             argv[i] = NULL;
 631           }
 632     }
 633
 634   mount_list =
 635     read_filesystem_list ((fs_select_list != NULL
 636                            || fs_exclude_list != NULL
 637                            || print_type),
 638                           show_all_fs);
 639
 640   if (mount_list == NULL)
 641     error (1, errno, _("cannot read table of mounted filesystems"));
 642
 643   print_header ();
 644   if (require_sync)
 645     sync ();
 646
 647   if (optind == argc)
 648     show_all_entries ();
 649   else
 650     {
 651       /* Display explicitly requested empty filesystems. */
 652       show_listed_fs = 1;
 653
 654       for (i = optind; i < argc; ++i)
 655         if (argv[i])
 656           show_entry (argv[i], &stats[i - optind]);
 657     }
 658
 659   exit (exit_status);
 660 }
 661