uptime: simplify following gnulib changes

* build-aux/gen-lists-of-programs.sh (build_if_possible_progs):
Remove uptime.
(normal_progs): Add uptime.
* configure.ac: Remove GNULIB_BOOT_TIME invocation.
* m4/boottime.m4: Remove file.
* src/uptime.c: Don't include <sys/sysctl.h>, <OS.h>.
(print_uptime): Don't call sysctl, get_system_info, as Gnulib's
readutmp module now does this.

build-aux/gen-lists-of-programs.sh

@@ -33,7 +33,6 @@ build_if_possible_progs='
     stdbuf
     stty
     timeout
-    uptime
     users
     who
 '
@@ -132,6 +131,7 @@ normal_progs='
     unexpand
     uniq
     unlink
+    uptime
     vdir
     wc
     whoami

configure.ac

@@ -406,8 +406,6 @@ AC_DEFUN([coreutils_DUMMY_1],
 ])
 coreutils_DUMMY_1
 
-GNULIB_BOOT_TIME([gl_ADD_PROG([optional_bin_progs], [uptime])])
-
 AC_SYS_POSIX_TERMIOS()
 gl_HEADER_TIOCGWINSZ_NEEDS_SYS_IOCTL
 

m4/boottime.m4

@@ -1,65 +0,0 @@
-# boottime.m4 serial 4
-# Determine whether this system has infrastructure for obtaining the boot time.
-
-# Copyright (C) 1996-2023 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 3 of the License, 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, see <https://www.gnu.org/licenses/>.
-
-# GNULIB_BOOT_TIME([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
-* ----------------------------------------------------------
-AC_DEFUN([GNULIB_BOOT_TIME],
-[
-  AC_CHECK_FUNCS([sysctl])
-  AC_CHECK_HEADERS_ONCE([sys/param.h])
-  AC_CHECK_HEADERS([sys/sysctl.h], [], [],
-    [AC_INCLUDES_DEFAULT
-     [#if HAVE_SYS_PARAM_H
-       #include <sys/param.h>
-      #endif]])
-  AC_CHECK_HEADERS_ONCE([utmpx.h OS.h])
-  AC_CACHE_CHECK(
-    [whether we can get the system boot time],
-    [gnulib_cv_have_boot_time],
-    [
-      AC_COMPILE_IFELSE(
-       [AC_LANG_PROGRAM(
-[AC_INCLUDES_DEFAULT
-#if HAVE_SYSCTL && HAVE_SYS_SYSCTL_H
-# if HAVE_SYS_PARAM_H
-#  include <sys/param.h> /* needed for OpenBSD 3.0 */
-# endif
-# include <sys/sysctl.h>
-#endif
-#if HAVE_UTMPX_H
-# include <utmpx.h>
-#endif
-#include <utmp.h>
-#if HAVE_OS_H
-# include <OS.h>
-#endif
-],
-[[
-#if (defined BOOT_TIME                              \
-     || (defined CTL_KERN && defined KERN_BOOTTIME) \
-     || HAVE_OS_H)
-/* your system *does* have the infrastructure to determine boot time */
-#else
-please_tell_us_how_to_determine_boot_time_on_your_system
-#endif
-]])],
-       [gnulib_cv_have_boot_time=yes],
-       [gnulib_cv_have_boot_time=no])
-    ])
-  AS_IF([test $gnulib_cv_have_boot_time = yes], [$1], [$2])
-])

src/uptime.c

@@ -24,14 +24,6 @@
 
 #include "system.h"
 
-#if HAVE_SYSCTL && HAVE_SYS_SYSCTL_H && ! defined __GLIBC__
-# include <sys/sysctl.h>
-#endif
-
-#if HAVE_OS_H
-# include <OS.h>
-#endif
-
 #include "long-options.h"
 #include "quote.h"
 #include "readutmp.h"
@@ -51,28 +43,6 @@ print_uptime (idx_t n, struct gl_utmp const *utmp_buf)
   int status = EXIT_SUCCESS;
   time_t boot_time = 0;
 
-#if HAVE_SYSCTL && ! defined __GLIBC__ \
-    && defined CTL_KERN && defined KERN_BOOTTIME
-  {
-    /* FreeBSD specific: fetch sysctl "kern.boottime".  */
-    static int request[2] = { CTL_KERN, KERN_BOOTTIME };
-    struct timeval result;
-    size_t result_len = sizeof result;
-
-    if (sysctl (request, 2, &result, &result_len, nullptr, 0) >= 0)
-      boot_time = result.tv_sec;
-  }
-#endif
-
-#if HAVE_OS_H /* BeOS */
-  {
-    system_info si;
-
-    get_system_info (&si);
-    boot_time = si.boot_time / 1000000;
-  }
-#endif
-
   /* Loop through all the utmp entries we just read and count up the valid
      ones, also in the process possibly gleaning boottime. */
   idx_t entries = 0;