+static void
+stat_on_signal (int signo)
+{
+#ifdef HAVE_SIGACTION
+# ifndef SA_RESTART
+# define SA_RESTART 0
+# endif
+ struct sigaction act;
+ act.sa_handler = sigstat;
+ sigemptyset (&act.sa_mask);
+ act.sa_flags = SA_RESTART;
+ sigaction (signo, &act, NULL);
+#else
+ signal (signo, sigstat);
+#endif
+}
+
+static void
+set_stat_signal (const char *name)
+{
+ static struct sigtab
+ {
+ char const *name;
+ int signo;
+ } const sigtab[] = {
+ { "SIGUSR1", SIGUSR1 },
+ { "USR1", SIGUSR1 },
+ { "SIGUSR2", SIGUSR2 },
+ { "USR2", SIGUSR2 },
+ { "SIGHUP", SIGHUP },
+ { "HUP", SIGHUP },
+ { "SIGINT", SIGINT },
+ { "INT", SIGINT },
+ { "SIGQUIT", SIGQUIT },
+ { "QUIT", SIGQUIT }
+ };
+ struct sigtab const *p;
+
+ for (p = sigtab; p < sigtab + sizeof (sigtab) / sizeof (sigtab[0]); p++)
+ if (strcmp (p->name, name) == 0)
+ {
+ stat_on_signal (p->signo);
+ return;
+ }
+ FATAL_ERROR ((0, 0, _("Unknown signal name: %s"), name));
+}
+
+\f
+struct textual_date
+{
+ struct textual_date *next;
+ struct timespec ts;
+ const char *option;
+ char *date;
+};
+
+static int
+get_date_or_file (struct tar_args *args, const char *option,
+ const char *str, struct timespec *ts)
+{
+ if (FILE_SYSTEM_PREFIX_LEN (str) != 0
+ || ISSLASH (*str)
+ || *str == '.')
+ {
+ struct stat st;
+ if (stat (str, &st) != 0)
+ {
+ stat_error (str);
+ USAGE_ERROR ((0, 0, _("Date sample file not found")));
+ }
+ *ts = get_stat_mtime (&st);
+ }
+ else
+ {
+ if (! parse_datetime (ts, str, NULL))
+ {
+ WARN ((0, 0, _("Substituting %s for unknown date format %s"),
+ tartime (*ts, false), quote (str)));
+ ts->tv_nsec = 0;
+ return 1;
+ }
+ else
+ {
+ struct textual_date *p = xmalloc (sizeof (*p));
+ p->ts = *ts;
+ p->option = option;
+ p->date = xstrdup (str);
+ p->next = args->textual_date;
+ args->textual_date = p;
+ }
+ }
+ return 0;
+}
+
+static void
+report_textual_dates (struct tar_args *args)
+{
+ struct textual_date *p;
+ for (p = args->textual_date; p; )
+ {
+ struct textual_date *next = p->next;
+ if (verbose_option)
+ {
+ char const *treated_as = tartime (p->ts, true);
+ if (strcmp (p->date, treated_as) != 0)
+ WARN ((0, 0, _("Option %s: Treating date '%s' as %s"),
+ p->option, p->date, treated_as));
+ }
+ free (p->date);
+ free (p);
+ p = next;
+ }
+}
+
+\f
+static bool files_from_option; /* When set, tar will not refuse to create
+ empty archives */
+
+/* Default density numbers for [0-9][lmh] device specifications */
+
+#if defined DEVICE_PREFIX && !defined DENSITY_LETTER
+# ifndef LOW_DENSITY_NUM
+# define LOW_DENSITY_NUM 0
+# endif
+
+# ifndef MID_DENSITY_NUM
+# define MID_DENSITY_NUM 8
+# endif
+
+# ifndef HIGH_DENSITY_NUM
+# define HIGH_DENSITY_NUM 16
+# endif
+#endif
+
+\f
+static char *
+tar_help_filter (int key, const char *text, void *input)
+{
+ struct obstack stk;
+ char *s;
+
+ switch (key)
+ {
+ default:
+ s = (char*) text;
+ break;
+
+ case 'j':
+ s = xasprintf (_("filter the archive through %s"), BZIP2_PROGRAM);
+ break;
+
+ case 'z':
+ s = xasprintf (_("filter the archive through %s"), GZIP_PROGRAM);
+ break;
+
+ case 'Z':
+ s = xasprintf (_("filter the archive through %s"), COMPRESS_PROGRAM);
+ break;
+
+ case LZIP_OPTION:
+ s = xasprintf (_("filter the archive through %s"), LZIP_PROGRAM);
+ break;
+
+ case LZMA_OPTION:
+ s = xasprintf (_("filter the archive through %s"), LZMA_PROGRAM);
+ break;
+
+ case LZOP_OPTION:
+ s = xasprintf (_("filter the archive through %s"), LZOP_PROGRAM);
+
+ case 'J':
+ s = xasprintf (_("filter the archive through %s"), XZ_PROGRAM);
+ break;
+
+ case ARGP_KEY_HELP_EXTRA:
+ {
+ const char *tstr;
+
+ obstack_init (&stk);
+ tstr = _("Valid arguments for the --quoting-style option are:");
+ obstack_grow (&stk, tstr, strlen (tstr));
+ obstack_grow (&stk, "\n\n", 2);
+ tar_list_quoting_styles (&stk, " ");
+ tstr = _("\n*This* tar defaults to:\n");
+ obstack_grow (&stk, tstr, strlen (tstr));
+ s = format_default_settings ();
+ obstack_grow (&stk, s, strlen (s));
+ obstack_1grow (&stk, '\n');
+ obstack_1grow (&stk, 0);
+ s = xstrdup (obstack_finish (&stk));
+ obstack_free (&stk, NULL);
+ }
+ }
+ return s;
+}
+\f
+static char *
+expand_pax_option (struct tar_args *targs, const char *arg)