moving getloadavg and fnmatch from Autoconf to Gnulib (1/2)

[Paul Eggert]

getloadavg and fnmatch properly belong to Gnulib, but for historical
reasons the M4 macros are defined in Autoconf.  This just bit me with
coreutils, since getloadavg no longer configures itself properly on
Solaris 8 for two reasons: first, it unconditionally includes
<stdbool.h> which doesn't exist, and second, with the config-h module,
it unconditionally includes <config.h>, which doesn't exist either.

One way to fix this is to migrate the relevant test into the Autoconf
code, so that it no longer uses getloadavg.c, but the test is really
tricky and for now I'd just like to fix things.

I looked for other Gnulib modules that use Autoconf macros that
include Gnulib source code, and found that fnmatch does it too.
Both of these modules should simply be migrated into Gnulib;
they don't really belong in Autoconf.  To start this process I've
installed the following patch, which fixes the Gnulib side.

2006-08-31  Paul Eggert  <address@hidden>

        * modules/getloadavg (Files): Add m4/getloadavg.m4.
        (configure.ac): AC_FUNC_GETLOADAVG -> gl_GETLOADAVG, as
        the former is now obsolescent.
        * lib/getloadavg.c [defined gl_GETLOADAVG]: Don't include config.h
        or stdbool.h, because they might not exist while configuring.
        * m4/fnmatch.m4: Add comment that Autoconf AC_FUNC_FNMATCH is
        obsolescent, and programs should use gnulib instead.
        * m4/getloadavg.m4: New file, with contents taken from Autoconf
        but with prefixes changed.

--- modules/getloadavg  26 Feb 2006 08:45:03 -0000      1.11
+++ modules/getloadavg  31 Aug 2006 22:23:28 -0000
@@ -3,6 +3,7 @@ Return the current system load averages.
 
 Files:
 lib/getloadavg.c
+m4/getloadavg.m4
 
 Depends-on:
 cloexec
@@ -13,7 +14,7 @@ stdbool
 fcntl-safer
 
 configure.ac:
-AC_FUNC_GETLOADAVG
+gl_GETLOADAVG
 
 Makefile.am:
 
--- lib/getloadavg.c    11 Jul 2006 04:07:59 -0000      1.31
+++ lib/getloadavg.c    31 Aug 2006 22:23:28 -0000
@@ -80,13 +80,20 @@
    We also #define LDAV_PRIVILEGED if a program will require
    special installation to be able to call getloadavg.  */
 
-/* This should always be first.  */
+/* "configure" defines gl_GETLOADAVG to sidestep problems with
+   partially-configured source directories.  */
+
 #ifdef HAVE_CONFIG_H
-# include <config.h>
+# ifndef gl_GETLOADAVG
+#  include <config.h>
+# endif
+#endif
+
+#ifndef gl_GETLOADAVG
+# include <stdbool.h>
 #endif
 
 #include <errno.h>
-#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 
--- m4/fnmatch.m4       6 Jul 2006 21:51:33 -0000       1.23
+++ m4/fnmatch.m4       31 Aug 2006 22:23:28 -0000
@@ -1,14 +1,14 @@
 # Check for fnmatch.
 
-# This is a modified version of autoconf's AC_FUNC_FNMATCH.
-# This file should be simplified after Autoconf 2.57 is required.
-
 # Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
 # Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
+# Autoconf defines AC_FUNC_FNMATCH, but that is obsolescent.
+# New applications should use the macros below instead.
+
 # _AC_FUNC_FNMATCH_IF(STANDARD = GNU | POSIX, CACHE_VAR, IF-TRUE, IF-FALSE)
 # -------------------------------------------------------------------------
 # If a STANDARD compliant fnmatch is found, run IF-TRUE, otherwise
--- /dev/null   2005-09-24 22:00:15.000000000 -0700
+++ m4/getloadavg.m4    2006-08-31 14:16:56.000000000 -0700
@@ -0,0 +1,156 @@
+# Check for getloadavg.
+
+# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1999, 2000, 2002, 2003,
+# 2006 Free Software Foundation, Inc.
+
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# Autoconf defines AC_FUNC_GETLOADAVG, but that is obsolescent.
+# New applications should use gl_GETLOADAVG instead.
+
+# gl_PREREQ_GETLOADAVG
+# --------------------
+# Set up the AC_LIBOBJ replacement of `getloadavg'.
+m4_define([gl_PREREQ_GETLOADAVG],
+[AC_LIBOBJ(getloadavg)
+AC_DEFINE(C_GETLOADAVG, 1, [Define to 1 if using `getloadavg.c'.])
+# Figure out what our getloadavg.c needs.
+gl_have_func=no
+AC_CHECK_HEADER(sys/dg_sys_info.h,
+[gl_have_func=yes
+ AC_DEFINE(DGUX, 1, [Define to 1 for DGUX with <sys/dg_sys_info.h>.])
+ AC_CHECK_LIB(dgc, dg_sys_info)])
+
+# We cannot check for <dwarf.h>, because Solaris 2 does not use dwarf (it
+# uses stabs), but it is still SVR4.  We cannot check for <elf.h> because
+# Irix 4.0.5F has the header but not the library.
+if test $gl_have_func = no && test "$ac_cv_lib_elf_elf_begin" = yes; then
+  gl_have_func=yes
+  AC_DEFINE(SVR4, 1, [Define to 1 on System V Release 4.])
+fi
+
+if test $gl_have_func = no; then
+  AC_CHECK_HEADER(inq_stats/cpustats.h,
+  [gl_have_func=yes
+   AC_DEFINE(UMAX, 1, [Define to 1 for Encore UMAX.])
+   AC_DEFINE(UMAX4_3, 1,
+            [Define to 1 for Encore UMAX 4.3 that has <inq_status/cpustats.h>
+             instead of <sys/cpustats.h>.])])
+fi
+
+if test $gl_have_func = no; then
+  AC_CHECK_HEADER(sys/cpustats.h,
+  [gl_have_func=yes; AC_DEFINE(UMAX)])
+fi
+
+if test $gl_have_func = no; then
+  AC_CHECK_HEADERS(mach/mach.h)
+fi
+
+AC_CHECK_HEADERS(nlist.h,
+[AC_CHECK_MEMBERS([struct nlist.n_un.n_name],
+                 [AC_DEFINE(NLIST_NAME_UNION, 1,
+                            [Define to 1 if your `struct nlist' has an
+                             `n_un' member.  Obsolete, depend on
+                             `HAVE_STRUCT_NLIST_N_UN_N_NAME])], [],
+                 address@hidden:@include <nlist.h>])
+])dnl
+])# gl_PREREQ_GETLOADAVG
+
+
+# gl_GETLOADAVG
+# -------------
+AN_FUNCTION([getloadavg], [gl_GETLOADAVG])
+AC_DEFUN([gl_GETLOADAVG],
+[gl_have_func=no # yes means we've found a way to get the load average.
+
+# Make sure getloadavg.c is where it belongs, at configure-time.
+test -f "$srcdir/$ac_config_libobj_dir/getloadavg.c" ||
+  AC_MSG_ERROR([$srcdir/$ac_config_libobj_dir/getloadavg.c is missing])
+
+gl_save_LIBS=$LIBS
+
+# Check for getloadavg, but be sure not to touch the cache variable.
+(AC_CHECK_FUNC(getloadavg, exit 0, exit 1)) && gl_have_func=yes
+
+# On HPUX9, an unprivileged user can get load averages through this function.
+AC_CHECK_FUNCS(pstat_getdynamic)
+
+# Solaris has libkstat which does not require root.
+AC_CHECK_LIB(kstat, kstat_open)
+test $ac_cv_lib_kstat_kstat_open = yes && gl_have_func=yes
+
+# Some systems with -lutil have (and need) -lkvm as well, some do not.
+# On Solaris, -lkvm requires nlist from -lelf, so check that first
+# to get the right answer into the cache.
+# For kstat on solaris, we need libelf to force the definition of SVR4 below.
+if test $gl_have_func = no; then
+  AC_CHECK_LIB(elf, elf_begin, LIBS="-lelf $LIBS")
+fi
+if test $gl_have_func = no; then
+  AC_CHECK_LIB(kvm, kvm_open, LIBS="-lkvm $LIBS")
+  # Check for the 4.4BSD definition of getloadavg.
+  AC_CHECK_LIB(util, getloadavg,
+    [LIBS="-lutil $LIBS" gl_have_func=yes gl_cv_func_getloadavg_setgid=yes])
+fi
+
+if test $gl_have_func = no; then
+  # There is a commonly available library for RS/6000 AIX.
+  # Since it is not a standard part of AIX, it might be installed locally.
+  gl_getloadavg_LIBS=$LIBS
+  LIBS="-L/usr/local/lib $LIBS"
+  AC_CHECK_LIB(getloadavg, getloadavg,
+              [LIBS="-lgetloadavg $LIBS"], [LIBS=$gl_getloadavg_LIBS])
+fi
+
+# Make sure it is really in the library, if we think we found it,
+# otherwise set up the replacement function.
+AC_CHECK_FUNCS(getloadavg, [],
+              [gl_PREREQ_GETLOADAVG])
+
+# Some definitions of getloadavg require that the program be installed setgid.
+AC_CACHE_CHECK(whether getloadavg requires setgid,
+              gl_cv_func_getloadavg_setgid,
+[AC_EGREP_CPP([Yowza Am I SETGID yet],
+[#define gl_GETLOADAVG
+#include "$srcdir/$ac_config_libobj_dir/getloadavg.c"
+#ifdef LDAV_PRIVILEGED
+Yowza Am I SETGID yet
+#endif
+],
+             gl_cv_func_getloadavg_setgid=yes,
+             gl_cv_func_getloadavg_setgid=no)])
+if test $gl_cv_func_getloadavg_setgid = yes; then
+  NEED_SETGID=true
+  AC_DEFINE(GETLOADAVG_PRIVILEGED, 1,
+           [Define to 1 if the `getloadavg' function needs to be run setuid
+            or setgid.])
+else
+  NEED_SETGID=false
+fi
+AC_SUBST(NEED_SETGID)dnl
+
+if test $gl_cv_func_getloadavg_setgid = yes; then
+  AC_CACHE_CHECK(group of /dev/kmem, gl_cv_group_kmem,
+[ # On Solaris, /dev/kmem is a symlink.  Get info on the real file.
+  ac_ls_output=`ls -lgL /dev/kmem 2>/dev/null`
+  # If we got an error (system does not support symlinks), try without -L.
+  test -z "$ac_ls_output" && ac_ls_output=`ls -lg /dev/kmem`
+  gl_cv_group_kmem=`echo $ac_ls_output \
+    | sed -ne ['s/[     ][      ]*/ /g;
+              s/^.[sSrwx-]* *[0-9]* *\([^0-9]*\)  *.*/\1/;
+              / /s/.* //;p;']`
+])
+  AC_SUBST(KMEM_GROUP, $gl_cv_group_kmem)dnl
+fi
+if test "x$gl_save_LIBS" = x; then
+  GETLOADAVG_LIBS=$LIBS
+else
+  GETLOADAVG_LIBS=`echo "$LIBS" | sed "s!$gl_save_LIBS!!"`
+fi
+LIBS=$gl_save_LIBS
+
+AC_SUBST(GETLOADAVG_LIBS)dnl
+])# gl_GETLOADAVG