ls.c

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      && !strncmp (color_indicator[C_LINK].string, "target", 6))
    color_symlink_as_referent = 1;
}

/* Request that the directory named NAME have its contents listed later.
   If REALNAME is nonzero, it will be used instead of NAME when the
   directory name is printed.  This allows symbolic links to directories
   to be treated as regular directories but still be listed under their
   real names.  NAME == NULL is used to insert a marker entry for the
   directory named in REALNAME.
   If F is non-NULL, we use its dev/ino information to save
   a call to stat -- when doing a recursive (-R) traversal.  */

static void
queue_directory (const char *name, const char *realname)
{
  struct pending *new;

  new = XMALLOC (struct pending, 1);
  new->realname = realname ? xstrdup (realname) : NULL;
  new->name = name ? xstrdup (name) : NULL;
  new->next = pending_dirs;
  pending_dirs = new;
}

/* Read directory `name', and list the files in it.
   If `realname' is nonzero, print its name instead of `name';
   this is used for symbolic links to directories. */

static void
print_dir (const char *name, const char *realname)
{
  register DIR *reading;
  register struct dirent *next;
  register uintmax_t total_blocks = 0;
  static int first = 1;

  errno = 0;
  reading = opendir (name);
  if (!reading)
    {
      error (0, errno, "%s", quotearg_colon (name));
      exit_status = 1;
      return;
    }

  if (LOOP_DETECT)
    {
      struct stat dir_stat;
      int fd = dirfd (reading);

      /* If dirfd failed, endure the overhead of using stat.  */
      if ((0 <= fd
	   ? fstat (fd, &dir_stat)
	   : stat (name, &dir_stat)) < 0)
	{
	  error (0, errno, _("cannot determine device and inode of %s"),
		 quotearg_colon (name));
	  exit_status = 1;
	  return;
	}

      /* If we've already visited this dev/inode pair, warn that
	 we've found a loop, and do not process this directory.  */
      if (visit_dir (dir_stat.st_dev, dir_stat.st_ino))
	{
	  error (0, 0, _("not listing already-listed directory: %s"),
		 quotearg_colon (name));
	  return;
	}

      DEV_INO_PUSH (dir_stat.st_dev, dir_stat.st_ino);
    }

  /* Read the directory entries, and insert the subfiles into the `files'
     table.  */

  clear_files ();

  while ((next = readdir (reading)) != NULL)
    if (file_interesting (next))
      {
	enum filetype type = unknown;

#if HAVE_STRUCT_DIRENT_D_TYPE
	if (next->d_type == DT_DIR || next->d_type == DT_CHR
	    || next->d_type == DT_BLK || next->d_type == DT_SOCK
	    || next->d_type == DT_FIFO)
	  type = next->d_type;
#endif
	total_blocks += gobble_file (next->d_name, type, 0, name);
      }

  if (CLOSEDIR (reading))
    {
      error (0, errno, "%s", quotearg_colon (name));
      exit_status = 1;
      /* Don't return; print whatever we got. */
    }

  /* Sort the directory contents.  */
  sort_files ();

  /* If any member files are subdirectories, perhaps they should have their
     contents listed rather than being mentioned here as files.  */

  if (recursive)
    extract_dirs_from_files (name, 1);

  if (recursive || print_dir_name)
    {
      if (!first)
	DIRED_PUTCHAR ('\n');
      first = 0;
      DIRED_INDENT ();
      PUSH_CURRENT_DIRED_POS (&subdired_obstack);
      dired_pos += quote_name (stdout, realname ? realname : name,
			       dirname_quoting_options);
      PUSH_CURRENT_DIRED_POS (&subdired_obstack);
      DIRED_FPUTS_LITERAL (":\n", stdout);
    }

  if (format == long_format || print_block_size)
    {
      const char *p;
      char buf[LONGEST_HUMAN_READABLE + 1];

      DIRED_INDENT ();
      p = _("total");
      DIRED_FPUTS (p, stdout, strlen (p));
      DIRED_PUTCHAR (' ');
      p = human_readable_inexact (total_blocks, buf, ST_NBLOCKSIZE,
				  output_block_size, human_ceiling);
      DIRED_FPUTS (p, stdout, strlen (p));
      DIRED_PUTCHAR ('\n');
    }

  if (files_index)
    print_current_files ();
}

/* Add `pattern' to the list of patterns for which files that match are
   not listed.  */

static void
add_ignore_pattern (const char *pattern)
{
  register struct ignore_pattern *ignore;

  ignore = XMALLOC (struct ignore_pattern, 1);
  ignore->pattern = pattern;
  /* Add it to the head of the linked list. */
  ignore->next = ignore_patterns;
  ignore_patterns = ignore;
}

/* Return nonzero if the file in `next' should be listed. */

static int
file_interesting (const struct dirent *next)
{
  register struct ignore_pattern *ignore;

  for (ignore = ignore_patterns; ignore; ignore = ignore->next)
    if (fnmatch (ignore->pattern, next->d_name, FNM_PERIOD) == 0)
      return 0;

  if (really_all_files
      || next->d_name[0] != '.'
      || (all_files
	  && next->d_name[1] != '\0'
	  && (next->d_name[1] != '.' || next->d_name[2] != '\0')))
    return 1;

  return 0;
}

/* Enter and remove entries in the table `files'.  */

/* Empty the table of files. */

static void
clear_files (void)
{
  register int i;

  for (i = 0; i < files_index; i++)
    {
      free (files[i].name);
      if (files[i].linkname)
	free (files[i].linkname);
    }

  files_index = 0;
  block_size_size = 4;
}

/* Add a file to the current table of files.
   Verify that the file exists, and print an error message if it does not.
   Return the number of blocks that the file occupies.  */

static uintmax_t
gobble_file (const char *name, enum filetype type, int explicit_arg,
	     const char *dirname)
{
  register uintmax_t blocks;
  register char *path;

  if (files_index == nfiles)
    {
      nfiles *= 2;
      files = XREALLOC (files, struct fileinfo, nfiles);
    }

  files[files_index].linkname = 0;
  files[files_index].linkmode = 0;
  files[files_index].linkok = 0;

  /* FIXME: this use of ls: `mkdir a; touch a/{b,c,d}; ls -R a'
     shouldn't require that ls stat b, c, and d -- at least
     not on systems with usable d_type.  The problem is that
     format_needs_stat is set, because of the -R.  */
  if (explicit_arg || format_needs_stat
      || (format_needs_type && type == unknown))
    {
      /* `path' is the absolute pathname of this file. */
      int val;

      if (name[0] == '/' || dirname[0] == 0)
	path = (char *) name;
      else
	{
	  path = (char *) alloca (strlen (name) + strlen (dirname) + 2);
	  attach (path, dirname, name);
	}

      val = (DEREF_ALWAYS <= dereference + explicit_arg
	     ? stat (path, &files[files_index].stat)
	     : lstat (path, &files[files_index].stat));

      if (val < 0)
	{
	  error (0, errno, "%s", quotearg_colon (path));
	  exit_status = 1;
	  return 0;
	}

#if HAVE_ACL
      if (format == long_format)
	{
	  int n = file_has_acl (path, &files[files_index].stat);
	  files[files_index].have_acl = (0 < n);
	  if (n < 0)
	    error (0, errno, "%s", quotearg_colon (path));
	}
#endif

      if (S_ISLNK (files[files_index].stat.st_mode)
	  && (format == long_format || check_symlink_color))
	{
	  char *linkpath;
	  struct stat linkstats;

	  get_link_name (path, &files[files_index]);
	  linkpath = make_link_path (path, files[files_index].linkname);

	  /* Avoid following symbolic links when possible, ie, when
	     they won't be traced and when no indicator is needed. */
	  if (linkpath
	      && (indicator_style != none || check_symlink_color)
	      && stat (linkpath, &linkstats) == 0)
	    {
	      files[files_index].linkok = 1;

	      /* Symbolic links to directories that are mentioned on the
	         command line are automatically traced if not being
	         listed as files.  */
	      if (explicit_arg && format != long_format
		  && S_ISDIR (linkstats.st_mode))
		{
		  /* Substitute the linked-to directory's name, but
		     save the real name in `linkname' for printing.  */
		  if (!immediate_dirs)
		    {
		      const char *tempname = name;
		      name = linkpath;
		      linkpath = files[files_index].linkname;
		      files[files_index].linkname = (char *) tempname;
		    }
		  files[files_index].stat = linkstats;
		}
	      else
		{
		  /* Get the linked-to file's mode for the filetype indicator
		     in long listings.  */
		  files[files_index].linkmode = linkstats.st_mode;
		  files[files_index].linkok = 1;
		}
	    }
	  if (linkpath)
	    free (linkpath);
	}

      if (S_ISLNK (files[files_index].stat.st_mode))
	files[files_index].filetype = symbolic_link;
      else if (S_ISDIR (files[files_index].stat.st_mode))
	{
	  if (explicit_arg && !immediate_dirs)
	    files[files_index].filetype = arg_directory;
	  else
	    files[files_index].filetype = directory;
	}
      else
	files[files_index].filetype = normal;

      blocks = ST_NBLOCKS (files[files_index].stat);
      {
	char buf[LONGEST_HUMAN_READABLE + 1];
	int len = strlen (human_readable_inexact (blocks, buf, ST_NBLOCKSIZE,
						  output_block_size,
						  human_ceiling));
	if (block_size_size < len)
	  block_size_size = len < 7 ? len : 7;
      }
    }
  else
    {
      files[files_index].filetype = type;
#if HAVE_STRUCT_DIRENT_D_TYPE
      files[files_index].stat.st_mode = DTTOIF (type);
#endif
      blocks = 0;
    }

  files[files_index].name = xstrdup (name);
  files_index++;

  return blocks;
}

#if HAVE_SYMLINKS

/* Put the name of the file that `filename' is a symbolic link to
   into the `linkname' field of `f'. */

static void
get_link_name (const char *filename, struct fileinfo *f)
{
  f->linkname = xreadlink (filename);
  if (f->linkname == NULL)
    {
      error (0, errno, _("cannot read symbolic link %s"),
	     quotearg_colon (filename));
      exit_status = 1;
    }
}

/* If `linkname' is a relative path and `path' contains one or more
   leading directories, return `linkname' with those directories
   prepended; otherwise, return a copy of `linkname'.
   If `linkname' is zero, return zero. */

static char *
make_link_path (const char *path, const char *linkname)
{
  char *linkbuf;
  size_t bufsiz;

  if (linkname == 0)
    return 0;

  if (*linkname == '/')
    return xstrdup (linkname);

  /* The link is to a relative path.  Prepend any leading path
     in `path' to the link name. */
  linkbuf = strrchr (path, '/');
  if (linkbuf == 0)
    return xstrdup (linkname);

  bufsiz = linkbuf - path + 1;
  linkbuf = xmalloc (bufsiz + strlen (linkname) + 1);
  strncpy (linkbuf, path, bufsiz);
  strcpy (linkbuf + bufsiz, linkname);
  return linkbuf;
}
#endif

/* Return nonzero if base_name (NAME) ends in `.' or `..'
   This is so we don't try to recurse on `././././. ...' */

static int
basename_is_dot_or_dotdot (const char *name)
{
  char const *base = base_name (name);
  return DOT_OR_DOTDOT (base);
}

/* Remove any entries from `files' that are for directories,
   and queue them to be listed as directories instead.
   `dirname' is the prefix to prepend to each dirname
   to make it correct relative to ls's working dir.
   If IGNORE_DOT_AND_DOT_DOT is nonzero don't treat `.' and `..' as dirs.
   This is desirable when processing directories recursively.  */

static void
extract_dirs_from_files (const char *dirname, int ignore_dot_and_dot_dot)
{
  register int i, j;

  if (*dirname && LOOP_DETECT)
    {
      /* Insert a marker entry first.  When we dequeue this marker entry,
	 we'll know that DIRNAME has been processed and may be removed
	 from the set of active directories.  */
      queue_directory (NULL, dirname);
    }

  /* Queue the directories last one first, because queueing reverses the
     order.  */
  for (i = files_index - 1; i >= 0; i--)
    if ((files[i].filetype == directory || files[i].filetype == arg_directory)
	&& (!ignore_dot_and_dot_dot
	    || !basename_is_dot_or_dotdot (files[i].name)))
      {
	if (files[i].name[0] == '/' || dirname[0] == 0)
	  {
	    queue_directory (files[i].name, files[i].linkname);
	  }
	else
	  {
	    char *path = path_concat (dirname, files[i].name, NULL);
	    queue_directory (path, files[i].linkname);
	    free (path);
	  }
	if (files[i].filetype == arg_directory)
	  free (files[i].name);
      }

  /* Now delete the directories from the table, compacting all the remaining
     entries.  */

  for (i = 0, j = 0; i < files_index; i++)
    if (files[i].filetype != arg_directory)
      files[j++] = files[i];
  files_index = j;
}

/* Use strcoll to compare strings in this locale.  If an error occurs,
   report an error and longjmp to failed_strcoll.  */

static jmp_buf failed_strcoll;

static int
xstrcoll (char const *a, char const *b)
{
  int diff;
  errno = 0;
  diff = strcoll (a, b);
  if (errno)
    {
      error (0, errno, _("cannot compare file names %s and %s"),
	     quote_n (0, a), quote_n (1, b));
      exit_status = 1;
      longjmp (failed_strcoll, 1);
    }
  return diff;
}

/* Comparison routines for sorting the files. */

typedef void const *V;

static inline int
cmp_ctime (struct fileinfo const *a, struct fileinfo const *b,
	   int (*cmp) PARAMS ((char const *, char const *)))
{
  int diff = CTIME_CMP (b->stat, a->stat);
  return diff ? diff : cmp (a->name, b->name);
}
static int compare_ctime (V a, V b) { return cmp_ctime (a, b, xstrcoll); }
static int compstr_ctime (V a, V b) { return cmp_ctime (a, b, strcmp); }
static int rev_cmp_ctime (V a, V b) { return compare_ctime (b, a); }
static int rev_str_ctime (V a, V b) { return compstr_ctime (b, a); }

static inline int
cmp_mtime (struct fileinfo const *a, struct fileinfo const *b,
	   int (*cmp) PARAMS((char const *, char const *)))
{
  int diff = MTIME_CMP (b->stat, a->stat);
  return diff ? diff : cmp (a->name, b->name);
}
static int compare_mtime (V a, V b) { return cmp_mtime (a, b, xstrcoll); }
static int compstr_mtime (V a, V b) { return cmp_mtime (a, b, strcmp); }
static int rev_cmp_mtime (V a, V b) { return compare_mtime (b, a); }
static int rev_str_mtime (V a, V b) { return compstr_mtime (b, a); }

static inline int
cmp_atime (struct fileinfo const *a, struct fileinfo const *b,
	   int (*cmp) PARAMS ((char const *, char const