path: root/src/du.c

/* du -- summarize disk usage
   Copyright (C) 1988-1991, 1995-2005 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/* Differences from the Unix du:
   * Doesn't simply ignore the names of regular files given as arguments
     when -a is given.

   By tege@sics.se, Torbjorn Granlund,
   and djm@ai.mit.edu, David MacKenzie.
   Variable blocks added by lm@sgi.com and eggert@twinsun.com.
   Rewritten to use nftw, then to use fts by Jim Meyering.  */

#include <config.h>
#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
#include <assert.h>
#include "system.h"
#include "argmatch.h"
#include "dirname.h" /* for strip_trailing_slashes */
#include "error.h"
#include "exclude.h"
#include "hash.h"
#include "human.h"
#include "inttostr.h"
#include "quote.h"
#include "quotearg.h"
#include "readtokens0.h"
#include "same.h"
#include "strftime.h"
#include "xfts.h"
#include "xstrtol.h"

extern bool fts_debug;

/* The official name of this program (e.g., no `g' prefix).  */
#define PROGRAM_NAME "du"

#define AUTHORS \
  "Torbjorn Granlund", "David MacKenzie, Paul Eggert", "Jim Meyering"

#if DU_DEBUG
# define FTS_CROSS_CHECK(Fts) fts_cross_check (Fts)
# define DEBUG_OPT "d"
#else
# define FTS_CROSS_CHECK(Fts)
# define DEBUG_OPT
#endif

/* Initial size of the hash table.  */
#define INITIAL_TABLE_SIZE 103

/* Hash structure for inode and device numbers.  The separate entry
   structure makes it easier to rehash "in place".  */

struct entry
{
  ino_t st_ino;
  dev_t st_dev;
};

/* A set of dev/ino pairs.  */
static Hash_table *htab;

/* Define a class for collecting directory information. */

struct duinfo
{
  /* Size of files in directory.  */
  uintmax_t size;

  /* Latest time stamp found.  If dmax == TYPE_MINIMUM (time_t) && nsec < 0,
     no time stamp has been found.  */
  time_t dmax;
  int nsec;
};

/* Initialize directory data.  */
static inline void
duinfo_init (struct duinfo *a)
{
  a->size = 0;
  a->dmax = TYPE_MINIMUM (time_t);
  a->nsec = -1;
}

/* Set directory data.  */
static inline void
duinfo_set (struct duinfo *a, uintmax_t size, time_t dmax, int nsec)
{
  a->size = size;
  a->dmax = dmax;
  a->nsec = nsec;
}

/* Accumulate directory data.  */
static inline void
duinfo_add (struct duinfo *a, struct duinfo const *b)
{
  a->size += b->size;
  if (a->dmax < b->dmax
      || (a->dmax == b->dmax && a->nsec < b->nsec))
    {
      a->dmax = b->dmax;
      a->nsec = b->nsec;
    }
}

/* A structure for per-directory level information.  */
struct dulevel
{
  /* Entries in this directory.  */
  struct duinfo ent;

  /* Total for subdirectories.  */
  struct duinfo subdir;
};

/* Name under which this program was invoked.  */
char *program_name;

/* If true, display counts for all files, not just directories.  */
static bool opt_all = false;

/* If true, rather than using the disk usage of each file,
   use the apparent size (a la stat.st_size).  */
static bool apparent_size = false;

/* If true, count each hard link of files with multiple links.  */
static bool opt_count_all = false;

/* If true, output the NUL byte instead of a newline at the end of each line. */
static bool opt_nul_terminate_output = false;

/* If true, print a grand total at the end.  */
static bool print_grand_total = false;

/* If nonzero, do not add sizes of subdirectories.  */
static bool opt_separate_dirs = false;

/* Show the total for each directory (and file if --all) that is at
   most MAX_DEPTH levels down from the root of the hierarchy.  The root
   is at level 0, so `du --max-depth=0' is equivalent to `du -s'.  */
static size_t max_depth = SIZE_MAX;

/* Human-readable options for output.  */
static int human_output_opts;

/* If true, print most recently modified date, using the specified format.  */
static bool opt_time = false;

/* Type of time to display. controlled by --time.  */

enum time_type
  {
    time_mtime,			/* default */
    time_ctime,
    time_atime
  };

static enum time_type time_type = time_mtime;

/* User specified date / time style */
static char *time_style = NULL;

/* Format used to display date / time. Controlled by --time-style */
static char const *time_format = NULL;

/* The units to use when printing sizes.  */
static uintmax_t output_block_size;

/* File name patterns to exclude.  */
static struct exclude *exclude;

/* Grand total size of all args, in bytes. Also latest modified date. */
static struct duinfo tot_dui = { 0, 0 };

#define IS_DIR_TYPE(Type)	\
  ((Type) == FTS_DP		\
   || (Type) == FTS_DNR)

/* For long options that have no equivalent short option, use a
   non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
enum
{
  APPARENT_SIZE_OPTION = CHAR_MAX + 1,
  EXCLUDE_OPTION,
  FILES0_FROM_OPTION,
  HUMAN_SI_OPTION,
  MAX_DEPTH_OPTION,
  TIME_OPTION,
  TIME_STYLE_OPTION
};

static struct option const long_options[] =
{
  {"all", no_argument, NULL, 'a'},
  {"apparent-size", no_argument, NULL, APPARENT_SIZE_OPTION},
  {"block-size", required_argument, NULL, 'B'},
  {"bytes", no_argument, NULL, 'b'},
  {"count-links", no_argument, NULL, 'l'},
  {"dereference", no_argument, NULL, 'L'},
  {"dereference-args", no_argument, NULL, 'D'},
  {"exclude", required_argument, NULL, EXCLUDE_OPTION},
  {"exclude-from", required_argument, NULL, 'X'},
  {"files0-from", required_argument, NULL, FILES0_FROM_OPTION},
  {"human-readable", no_argument, NULL, 'h'},
  {"si", no_argument, NULL, HUMAN_SI_OPTION},
  {"kilobytes", no_argument, NULL, 'k'}, /* long form is obsolescent */
  {"max-depth", required_argument, NULL, MAX_DEPTH_OPTION},
  {"null", no_argument, NULL, '0'},
  {"megabytes", no_argument, NULL, 'm'}, /* obsolescent */
  {"no-dereference", no_argument, NULL, 'P'},
  {"one-file-system", no_argument, NULL, 'x'},
  {"separate-dirs", no_argument, NULL, 'S'},
  {"summarize", no_argument, NULL, 's'},
  {"total", no_argument, NULL, 'c'},
  {"time", optional_argument, NULL, TIME_OPTION},
  {"time-style", required_argument, NULL, TIME_STYLE_OPTION},
  {GETOPT_HELP_OPTION_DECL},
  {GETOPT_VERSION_OPTION_DECL},
  {NULL, 0, NULL, 0}
};

static char const *const time_args[] =
{
  "atime", "access", "use", "ctime", "status", 0
};

static enum time_type const time_types[] =
{
  time_atime, time_atime, time_atime, time_ctime, time_ctime
};

/* `full-iso' uses full ISO-style dates and times.  `long-iso' uses longer
   ISO-style time stamps, though shorter than `full-iso'.  `iso' uses shorter
   ISO-style time stamps.  */
enum time_style
  {
    full_iso_time_style,       /* --time-style=full-iso */
    long_iso_time_style,       /* --time-style=long-iso */
    iso_time_style	       /* --time-style=iso */
  };

static char const *const time_style_args[] =
{
  "full-iso", "long-iso", "iso", NULL
};

static enum time_style const time_style_types[] =
{
  full_iso_time_style, long_iso_time_style, iso_time_style, 0
};

void
usage (int status)
{
  if (status != EXIT_SUCCESS)
    fprintf (stderr, _("Try `%s --help' for more information.\n"),
	     program_name);
  else
    {
      printf (_("\
Usage: %s [OPTION]... [FILE]...\n\
  or:  %s [OPTION]... --files0-from=F\n\
"), program_name, program_name);
      fputs (_("\
Summarize disk usage of each FILE, recursively for directories.\n\
\n\
"), stdout);
      fputs (_("\
Mandatory arguments to long options are mandatory for short options too.\n\
"), stdout);
      fputs (_("\
  -a, --all             write counts for all files, not just directories\n\
      --apparent-size   print apparent sizes, rather than disk usage; although\n\
                          the apparent size is usually smaller, it may be\n\
                          larger due to holes in (`sparse') files, internal\n\
                          fragmentation, indirect blocks, and the like\n\
  -B, --block-size=SIZE use SIZE-byte blocks\n\
  -b, --bytes           equivalent to `--apparent-size --block-size=1'\n\
  -c, --total           produce a grand total\n\
  -D, --dereference-args  dereference FILEs that are symbolic links\n\
"), stdout);
      fputs (_("\
      --files0-from=F   summarize disk usage of the NUL-terminated file\n\
                          names specified in file F\n\
  -H                    like --si, but also evokes a warning; will soon\n\
                          change to be equivalent to --dereference-args (-D)\n\
  -h, --human-readable  print sizes in human readable format (e.g., 1K 234M 2G)\n\
      --si              like -h, but use powers of 1000 not 1024\n\
  -k                    like --block-size=1K\n\
  -l, --count-links     count sizes many times if hard linked\n\
"), stdout);
      fputs (_("\
  -L, --dereference     dereference all symbolic links\n\
  -P, --no-dereference  don't follow any symbolic links (this is the default)\n\
  -0, --null            end each output line with 0 byte rather than newline\n\
  -S, --separate-dirs   do not include size of subdirectories\n\
  -s, --summarize       display only a total for each argument\n\
"), stdout);
      fputs (_("\
  -x, --one-file-system  skip directories on different file systems\n\
  -X FILE, --exclude-from=FILE  Exclude files that match any pattern in FILE.\n\
      --exclude=PATTERN Exclude files that match PATTERN.\n\
      --max-depth=N     print the total for a directory (or file, with --all)\n\
                          only if it is N or fewer levels below the command\n\
                          line argument;  --max-depth=0 is the same as\n\
                          --summarize\n\
"), stdout);
      fputs (_("\
      --time            show time of the last modification of any file in the\n\
                          directory, or any of its subdirectories\n\
      --time=WORD       show time as WORD instead of modification time:\n\
                          atime, access, use, ctime or status\n\
      --time-style=STYLE show times using style STYLE:\n\
                          full-iso, long-iso, iso, +FORMAT\n\
                          FORMAT is interpreted like `date'\n\
"), stdout);
      fputs (HELP_OPTION_DESCRIPTION, stdout);
      fputs (VERSION_OPTION_DESCRIPTION, stdout);
      fputs (_("\n\
SIZE may be (or may be an integer optionally followed by) one of following:\n\
kB 1000, K 1024, MB 1000*1000, M 1024*1024, and so on for G, T, P, E, Z, Y.\n\
"), stdout);
      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    }
  exit (status);
}

static size_t
entry_hash (void const *x, size_t table_size)
{
  struct entry const *p = x;

  /* Ignoring the device number here should be fine.  */
  /* The cast to uintmax_t prevents negative remainders
     if st_ino is negative.  */
  return (uintmax_t) p->st_ino % table_size;
}

/* Compare two dev/ino pairs.  Return true if they are the same.  */
static bool
entry_compare (void const *x, void const *y)
{
  struct entry const *a = x;
  struct entry const *b = y;
  return SAME_INODE (*a, *b) ? true : false;
}

/* Try to insert the INO/DEV pair into the global table, HTAB.
   Return true if the pair is successfully inserted,
   false if the pair is already in the table.  */
static bool
hash_ins (ino_t ino, dev_t dev)
{
  struct entry *ent;
  struct entry *ent_from_table;

  ent = xmalloc (sizeof *ent);
  ent->st_ino = ino;
  ent->st_dev = dev;

  ent_from_table = hash_insert (htab, ent);
  if (ent_from_table == NULL)
    {
      /* Insertion failed due to lack of memory.  */
      xalloc_die ();
    }

  if (ent_from_table == ent)
    {
      /* Insertion succeeded.  */
      return true;
    }

  /* That pair is already in the table, so ENT was not inserted.  Free it.  */
  free (ent);

  return false;
}

/* Initialize the hash table.  */
static void
hash_init (void)
{
  htab = hash_initialize (INITIAL_TABLE_SIZE, NULL,
			  entry_hash, entry_compare, free);
  if (htab == NULL)
    xalloc_die ();
}

/* FIXME: this code is nearly identical to code in date.c  */
/* Display the date and time in WHEN/NSEC according to the format specified
   in TIME_FORMAT.  If TIME_FORMAT is NULL, use the standard output format.
   Return zero if successful.  */

static void
show_date (const char *format, time_t when, int nsec)
{
  struct tm *tm;
  char *out = NULL;
  size_t out_length = 0;

  tm = localtime (&when);
  if (! tm)
    {
      char buf[INT_BUFSIZE_BOUND (intmax_t)];
      error (0, 0, _("time %s is out of range"),
	     (TYPE_SIGNED (time_t)
	      ? imaxtostr (when, buf)
	      : umaxtostr (when, buf)));
      fputs (buf, stdout);
      return;
    }

  do
    {
      out = x2realloc (out, &out_length);

      /* Mark the first byte of the buffer so we can detect the case
         of nstrftime producing an empty string.  Otherwise, this loop
         would not terminate when date was invoked like this
         `LANG=de date +%p' on a system with good language support.  */
      out[0] = '\1';
    }
  while (nstrftime (out, out_length, format, tm, 0, nsec) == 0 && out[0]);

  fputs (out, stdout);
  free (out);
}

/* Print N_BYTES.  Convert it to a readable value before printing.  */

static void
print_only_size (uintmax_t n_bytes)
{
  char buf[LONGEST_HUMAN_READABLE + 1];
  fputs (human_readable (n_bytes, buf, human_output_opts,
			 1, output_block_size), stdout);
}

/* Print size (and optionally time) indicated by *PDUI, followed by STRING.  */

static void
print_size (const struct duinfo *pdui, const char *string)
{
  print_only_size (pdui->size);
  if (opt_time)
    {
      putchar ('\t');
      show_date (time_format, pdui->dmax, pdui->nsec);
    }
  printf ("\t%s%c", string, opt_nul_terminate_output ? '\0' : '\n');
  fflush (stdout);
}

/* This function is called once for every file system object that fts
   encounters.  fts does a depth-first traversal.  This function knows
   that and accumulates per-directory totals based on changes in
   the depth of the current entry.  It returns true on success.  */

static bool
process_file (FTS *fts, FTSENT *ent)
{
  bool ok;
  struct duinfo dui;
  struct duinfo dui_to_print;
  size_t level;
  static size_t prev_level;
  static size_t n_alloc;
  /* First element of the structure contains:
     The sum of the st_size values of all entries in the single directory
     at the corresponding level.  Although this does include the st_size
     corresponding to each subdirectory, it does not include the size of
     any file in a subdirectory. Also corresponding last modified date.
     Second element of the structure contains:
     The sum of the sizes of all entries in the hierarchy at or below the
     directory at the specified level.  */
  static struct dulevel *dulvl;
  bool print = true;

  const char *file = ent->fts_path;
  const struct stat *sb = ent->fts_statp;
  bool skip;

  /* If necessary, set FTS_SKIP before returning.  */
  skip = excluded_file_name (exclude, ent->fts_path);
  if (skip)
    fts_set (fts, ent, FTS_SKIP);

  switch (ent->fts_info)
    {
    case FTS_NS:
      error (0, ent->fts_errno, _("cannot access %s"), quote (file));
      return false;

    case FTS_ERR:
      /* if (S_ISDIR (ent->fts_statp->st_mode) && FIXME */
      error (0, ent->fts_errno, _("%s"), quote (file));
      return false;

    case FTS_DNR:
      /* Don't return just yet, since although the directory is not readable,
	 we were able to stat it, so we do have a size.  */
      error (0, ent->fts_errno, _("cannot read directory %s"), quote (file));
      ok = false;
      break;

    default:
      ok = true;
      break;
    }

  /* If this is the first (pre-order) encounter with a directory,
     or if it's the second encounter for a skipped directory, then
     return right away.  */
  if (ent->fts_info == FTS_D || skip)
    return ok;

  /* If the file is being excluded or if it has already been counted
     via a hard link, then don't let it contribute to the sums.  */
  if (skip
      || (!opt_count_all
	  && ! S_ISDIR (sb->st_mode)
	  && 1 < sb->st_nlink
	  && ! hash_ins (sb->st_ino, sb->st_dev)))
    {
      /* Note that we must not simply return here.
	 We still have to update prev_level and maybe propagate
	 some sums up the hierarchy.  */
      duinfo_init (&dui);
      print = false;
    }
  else
    {
      duinfo_set (&dui,
		  (apparent_size
		   ? sb->st_size
		   : ST_NBLOCKS (*sb) * ST_NBLOCKSIZE),
		  (time_type == time_ctime ? sb->st_ctime
		   : time_type == time_atime ? sb->st_atime
		   : sb->st_mtime),
		  (time_type == time_ctime ? TIMESPEC_NS (sb->st_ctim)
		   : time_type == time_atime ? TIMESPEC_NS (sb->st_atim)
		   : TIMESPEC_NS (sb->st_mtim)));
    }

  level = ent->fts_level;
  dui_to_print = dui;

  if (n_alloc == 0)
    {
      n_alloc = level + 10;
      dulvl = xcalloc (n_alloc, sizeof *dulvl);
    }
  else
    {
      if (level == prev_level)
	{
	  /* This is usually the most common case.  Do nothing.  */
	}
      else if (level > prev_level)
	{
	  /* Descending the hierarchy.
	     Clear the accumulators for *all* levels between prev_level
	     and the current one.  The depth may change dramatically,
	     e.g., from 1 to 10.  */
	  size_t i;

	  if (n_alloc <= level)
	    {
	      dulvl = xnrealloc (dulvl, level, 2 * sizeof *dulvl);
	      n_alloc = level * 2;
	    }

	  for (i = prev_level + 1; i <= level; i++)
	    {
	      duinfo_init (&dulvl[i].ent);
	      duinfo_init (&dulvl[i].subdir);
	    }
	}
      else /* level < prev_level */
	{
	  /* Ascending the hierarchy.
	     Process a directory only after all entries in that
	     directory have been processed.  When the depth decreases,
	     propagate sums from the children (prev_level) to the parent.
	     Here, the current level is always one smaller than the
	     previous one.  */
	  assert (level == prev_level - 1);
	  duinfo_add (&dui_to_print, &dulvl[prev_level].ent);
	  if (!opt_separate_dirs)
	    duinfo_add (&dui_to_print, &dulvl[prev_level].subdir);
	  duinfo_add (&dulvl[level].subdir, &dulvl[prev_level].ent);
	  duinfo_add (&dulvl[level].subdir, &dulvl[prev_level].subdir);
	}
    }

  prev_level = level;

  /* Let the size of a directory entry contribute to the total for the
     containing directory, unless --separate-dirs (-S) is specified.  */
  if ( ! (opt_separate_dirs && IS_DIR_TYPE (ent->fts_info)))
    duinfo_add (&dulvl[level].ent, &dui);

  /* Even if this directory is unreadable or we can't chdir into it,
     do let its size contribute to the total, ... */
  duinfo_add (&tot_dui, &dui);

  /* ... but don't print out a total for it, since without the size(s)
     of any potential entries, it could be very misleading.  */
  if (ent->fts_info == FTS_DNR)
    return ok;

  /* If we're not counting an entry, e.g., because it's a hard link
     to a file we've already counted (and --count-links), then don't
     print a line for it.  */
  if (!print)
    return ok;

  if ((IS_DIR_TYPE (ent->fts_info) && level <= max_depth)
      || ((opt_all && level <= max_depth) || level == 0))
    print_size (&dui_to_print, file);

  return ok;
}

/* Recursively print the sizes of the directories (and, if selected, files)
   named in FILES, the last entry of which is NULL.
   BIT_FLAGS controls how fts works.
   Return true if successful.  */

static bool
du_files (char **files, int bit_flags)
{
  bool ok = true;

  if (*files)
    {
      FTS *fts = xfts_open (files, bit_flags, NULL);

      while (1)
	{
	  FTSENT *ent;

	  ent = fts_read (fts);
	  if (ent == NULL)
	    {
	      if (errno != 0)
		{
		  /* FIXME: try to give a better message  */
		  error (0, errno, _("fts_read failed"));
		  ok = false;
		}
	      break;
	    }
	  FTS_CROSS_CHECK (fts);

	  ok &= process_file (fts, ent);
	}

      /* Ignore failure, since the only way it can do so is in failing to
	 return to the original directory, and since we're about to exit,
	 that doesn't matter.  */
      fts_close (fts);
    }

  if (print_grand_total)
    print_size (&tot_dui, _("total"));

  return ok;
}

int
main (int argc, char **argv)
{
  int c;
  char *cwd_only[2];
  bool max_depth_specified = false;
  char **files;
  bool ok = true;
  char *files_from = NULL;
  struct Tokens tok;

  /* Bit flags that control how fts works.  */
  int bit_flags = FTS_PHYSICAL | FTS_TIGHT_CYCLE_CHECK;

  /* If true, display only a total for each argument. */
  bool opt_summarize_only = false;

  cwd_only[0] = ".";
  cwd_only[1] = NULL;

  initialize_main (&argc, &argv);
  program_name = argv[0];
  setlocale (LC_ALL, "");
  bindtextdomain (PACKAGE, LOCALEDIR);
  textdomain (PACKAGE);

  atexit (close_stdout);

  exclude = new_exclude ();

  human_output_opts = human_options (getenv ("DU_BLOCK_SIZE"), false,
				     &output_block_size);

  while ((c = getopt_long (argc, argv, DEBUG_OPT "0abchHklmsxB:DLPSX:",
			   long_options, NULL)) != -1)
    {
      switch (c)
	{
#if DU_DEBUG
	case 'd':
	  fts_debug = true;
	  break;
#endif

	case '0':
	  opt_nul_terminate_output = true;
	  break;

	case 'a':
	  opt_all = true;
	  break;

	case APPARENT_SIZE_OPTION:
	  apparent_size = true;
	  break;

	case 'b':
	  apparent_size = true;
	  human_output_opts = 0;
	  output_block_size = 1;
	  break;

	case 'c':
	  print_grand_total = true;
	  break;

	case 'h':
	  human_output_opts = human_autoscale | human_SI | human_base_1024;
	  output_block_size = 1;
	  break;

	case 'H':
	  error (0, 0, _("WARNING: use --si, not -H; the meaning of the -H\
 option will soon\nchange to be the same as that of --dereference-args (-D)"));
	  /* fall through */
	case HUMAN_SI_OPTION:
	  human_output_opts = human_autoscale | human_SI;
	  output_block_size = 1;
	  break;

	case 'k':
	  human_output_opts = 0;
	  output_block_size = 1024;
	  break;

	case MAX_DEPTH_OPTION:		/* --max-depth=N */
	  {
	    unsigned long int tmp_ulong;
	    if (xstrtoul (optarg, NULL, 0, &tmp_ulong, NULL) == LONGINT_OK
		&& tmp_ulong <= SIZE_MAX)
	      {
		max_depth_specified = true;
		max_depth = tmp_ulong;
	      }
	    else
	      {
		error (0, 0, _("invalid maximum depth %s"),
		       quote (optarg));
		ok = false;
	      }
	  }
	  break;

	case 'm': /* obsolescent: FIXME: remove in 2005. */
	  human_output_opts = 0;
	  output_block_size = 1024 * 1024;
	  break;

	case 'l':
	  opt_count_all = true;
	  break;

	case 's':
	  opt_summarize_only = true;
	  break;

	case 'x':
	  bit_flags |= FTS_XDEV;
	  break;

	case 'B':
	  human_output_opts = human_options (optarg, true, &output_block_size);
	  break;

	case 'D': /* This will eventually be 'H' (-H), too.  */
	  bit_flags = FTS_COMFOLLOW;
	  break;

	case 'L': /* --dereference */
	  bit_flags = FTS_LOGICAL;
	  break;

	case 'P': /* --no-dereference */
	  bit_flags = FTS_PHYSICAL;
	  break;

	case 'S':
	  opt_separate_dirs = true;
	  break;

	case 'X':
	  if (add_exclude_file (add_exclude, exclude, optarg,
				EXCLUDE_WILDCARDS, '\n'))
	    {
	      error (0, errno, "%s", quotearg_colon (optarg));
	      ok = false;
	    }
	  break;

	case FILES0_FROM_OPTION:
	  files_from = optarg;
	  break;

	case EXCLUDE_OPTION:
	  add_exclude (exclude, optarg, EXCLUDE_WILDCARDS);
	  break;

	case TIME_OPTION:
	  opt_time = true;
	  time_type =
	    (optarg
	     ? XARGMATCH ("--time", optarg, time_args, time_types)
	     : time_mtime);
	  break;

	case TIME_STYLE_OPTION:
	  time_style = optarg;
	  break;

	case_GETOPT_HELP_CHAR;

	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);

	default:
	  ok = false;
	}
    }

  if (!ok)
    usage (EXIT_FAILURE);

  if (opt_all & opt_summarize_only)
    {
      error (0, 0, _("cannot both summarize and show all entries"));
      usage (EXIT_FAILURE);
    }

  if (opt_summarize_only && max_depth_specified && max_depth == 0)
    {
      error (0, 0,
	     _("warning: summarizing is the same as using --max-depth=0"));
    }

  if (opt_summarize_only && max_depth_specified && max_depth != 0)
    {
      unsigned long int d = max_depth;
      error (0, 0, _("warning: summarizing conflicts with --max-depth=%lu"), d);
      usage (EXIT_FAILURE);
    }

  if (opt_summarize_only)
    max_depth = 0;

  /* Process time style if printing last times.  */
  if (opt_time)
    {
      if (! time_style)
	{
	  time_style = getenv ("TIME_STYLE");

	  /* Ignore TIMESTYLE="locale", for compatibility with ls.  */
	  if (! time_style || STREQ (time_style, "locale"))
	    time_style = "long-iso";
	  else if (*time_style == '+')
	    {
	      /* Ignore anything after a newline, for compatibility
		 with ls.  */
	      char *p = strchr (time_style, '\n');
	      if (p)
		*p = '\0';
	    }
	  else
	    {
	      /* Ignore "posix-" prefix, for compatibility with ls.  */
	      static char const posix_prefix[] = "posix-";
	      while (strncmp (time_style, posix_prefix, sizeof posix_prefix - 1)
		     == 0)
		time_style += sizeof posix_prefix - 1;
	    }
	}

      if (*time_style == '+')
	time_format = time_style + 1;
      else
        {
          switch (XARGMATCH ("time style", time_style,
                             time_style_args, time_style_types))
            {
	    case full_iso_time_style:
	      time_format = "%Y-%m-%d %H:%M:%S.%N %z";
	      break;

	    case long_iso_time_style:
	      time_format = "%Y-%m-%d %H:%M";
	      break;

	    case iso_time_style:
	      time_format = "%Y-%m-%d";
	      break;
            }
        }
    }

  if (files_from)
    {
      FILE *istream;

      /* When using --files0-from=F, you may not specify any files
	 on the command-line.  */
      if (optind < argc)
	{
	  error (0, 0, _("extra operand %s"), quote (argv[optind]));
	  fprintf (stderr, "%s\n",
		   _("File operands cannot be combined with --files0-from."));
	  usage (EXIT_FAILURE);
	}

      istream = (STREQ (files_from, "-") ? stdin : fopen (files_from, "r"));
      if (istream == NULL)
	error (EXIT_FAILURE, errno, _("cannot open %s for reading"),
	       quote (files_from));

      readtokens0_init (&tok);

      if (! readtokens0 (istream, &tok) || fclose (istream) != 0)
	error (EXIT_FAILURE, 0, _("cannot read file names from %s"),
	       quote (files_from));

      files = tok.tok;
    }
  else
    {
      files = (optind < argc ? argv + optind : cwd_only);
    }

  /* Initialize the hash structure for inode numbers.  */
  hash_init ();

  /* Report and filter out any empty file names before invoking fts.
     This works around a glitch in fts, which fails immediately
     (without looking at the other file names) when given an empty
     file name.  */
  {
    size_t i = 0;
    size_t j;

    for (j = 0; ; j++)
      {
	if (i != j)
	  files[i] = files[j];

	if ( ! files[i])
	  break;

	if (files[i][0])
	  i++;
	else
	  {
	    if (files_from)
	      {
		/* Using the standard `filename:line-number:' prefix here is
		   not totally appropriate, since NUL is the separator, not NL,
		   but it might be better than nothing.  */
		unsigned long int file_number = j + 1;
		error (0, 0, "%s:%lu: %s", quotearg_colon (files_from),
		       file_number, _("invalid zero-length file name"));
	      }
	    else
	      error (0, 0, "%s", _("invalid zero-length file name"));
	  }
      }

    ok = (i == j);
  }

  ok &= du_files (files, bit_flags);

  /* This isn't really necessary, but it does ensure we
     exercise this function.  */
  if (files_from)
    readtokens0_free (&tok);

  hash_free (htab);

  exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
}