2011-02-15 Paul Eggert <eggert@cs.ucla.edu>
+ getloadavg: set errno
+ * lib/getloadavg.c: Set errno when returning -1. If no other
+ error number looks appropriate, set it to ENOSYS if the getloadavg
+ looks like it can't possibly ever work, ENOTSUP otherwise.
+ Suggested by Bruno Haible in
+ <http://lists.gnu.org/archive/html/bug-gnulib/2011-02/msg00187.html>.
+
+ getloadavg: trim unused parts and speed up 'configure'
+ * NEWS: Document this.
+ * lib/getloadavg.c: Ignore HAVE_GETLOADAVG; this file is now
+ always compiled if getloadavg is absent.
+ Move test code to ...
+ * tests/test-getloadavg.c: New file, containing previous
+ contents of test from lib/getloadavg.c. It also contains
+ suggestions by Bruno Haible in
+ <http://lists.gnu.org/archive/html/bug-gnulib/2011-02/msg00186.html>.
+ * modules/getloadavg-tests: New file.
+ * m4/getloadavg.m4 (gl_GETLOADAVG): Do not check for getloadavg twice.
+ Do tests in the same order as they're needed for getloadavg.c.
+ Omit setgid-related tests that generate symbols KMEM_GROUP,
+ NEET_SETGID, GETLOADAVG_PRIVILEGED; nobody seems to use those any more.
+ Do only the tests that are needed to see whether the system has
+ getloadavg, moving the other tests into ...
+ (gl_PREREQ_GETLOADAVG): ... here. Do not define obsolete symbol
+ NLIST_NAME_UNION; nobody should be using it. Do not define
+ symbols C_GETLOADAVG and HAVE_GETLOADAVG; they're no longer
+ relevant, as the user of this module shouldn't care how getloadavg
+ is implemented.
+
getloadavg: omit unused var
* lib/getloadavg.c (getloadavg): Omit unused local variable.
#include <errno.h>
#include <stdio.h>
-/* Exclude all the code except the test program at the end
- if the system has its own `getloadavg' function. */
-
-#ifndef HAVE_GETLOADAVG
-
# include <sys/types.h>
/* Both the Emacs and non-Emacs sections want this. Some
/* Put the 1 minute, 5 minute and 15 minute load averages
into the first NELEM elements of LOADAVG.
Return the number written (never more than 3, but may be less than NELEM),
- or -1 if an error occurred. */
+ or -1 (setting errno) if an error occurred. */
int
getloadavg (double loadavg[], int nelem)
# ifdef NO_GET_LOAD_AVG
# define LDAV_DONE
- /* Set errno to zero to indicate that there was no particular error;
- this function just can't work at all on this system. */
- errno = 0;
+ errno = ENOSYS;
elem = -1;
# endif
kstat_ctl_t *kc;
kstat_t *ksp;
kstat_named_t *kn;
+ int saved_errno;
kc = kstat_open ();
if (kc == 0)
}
}
+ saved_errno = errno;
kstat_close (kc);
+ errno = saved_errno;
# endif /* HAVE_LIBKSTAT */
# if !defined (LDAV_DONE) && defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
char ldavgbuf[3 * (INT_STRLEN_BOUND (int) + sizeof ".00 ")];
char const *ptr = ldavgbuf;
- int fd, count;
+ int fd, count, saved_errno;
fd = open (LINUX_LDAV_FILE, O_RDONLY);
if (fd == -1)
return -1;
count = read (fd, ldavgbuf, sizeof ldavgbuf - 1);
+ saved_errno = errno;
(void) close (fd);
+ errno = saved_errno;
if (count <= 0)
return -1;
ldavgbuf[count] = '\0';
if (! ('0' <= *ptr && *ptr <= '9'))
{
if (elem == 0)
- return -1;
+ {
+ errno = ENOTSUP;
+ return -1;
+ }
break;
}
&scale);
(void) fclose (fp);
if (count != 4)
- return -1;
+ {
+ errno = ENOTSUP;
+ return -1;
+ }
for (elem = 0; elem < nelem; elem++)
loadavg[elem] = (double) load_ave[elem] / (double) scale;
}
if (!getloadavg_initialized)
- return -1;
+ {
+ errno = ENOTSUP;
+ return -1;
+ }
# endif /* NeXT */
# if !defined (LDAV_DONE) && defined (UMAX)
}
if (!getloadavg_initialized)
- return -1;
+ {
+ errno = ENOTSUP;
+ return -1;
+ }
# endif /* ! defined LDAV_DONE && defined __VMS */
# if ! defined LDAV_DONE && defined LOAD_AVE_TYPE && ! defined __VMS
}
if (offset == 0 || !getloadavg_initialized)
- return -1;
+ {
+ errno = ENOTSUP;
+ return -1;
+ }
# endif /* ! defined LDAV_DONE && defined LOAD_AVE_TYPE && ! defined __VMS */
# if !defined (LDAV_DONE) && defined (LOAD_AVE_TYPE) /* Including VMS. */
# endif /* !LDAV_DONE && LOAD_AVE_TYPE */
# if !defined LDAV_DONE
- /* Set errno to zero to indicate that there was no particular error;
- this function just can't work at all on this system. */
- errno = 0;
+ errno = ENOSYS;
elem = -1;
# endif
return elem;
}
-
-#endif /* ! HAVE_GETLOADAVG */
-\f
-#ifdef TEST
-int
-main (int argc, char **argv)
-{
- int naptime = 0;
-
- if (argc > 1)
- naptime = atoi (argv[1]);
-
- while (1)
- {
- double avg[3];
- int loads;
-
- errno = 0; /* Don't be misled if it doesn't set errno. */
- loads = getloadavg (avg, 3);
- if (loads == -1)
- {
- perror ("Error getting load average");
- return EXIT_FAILURE;
- }
- if (loads > 0)
- printf ("1-minute: %f ", avg[0]);
- if (loads > 1)
- printf ("5-minute: %f ", avg[1]);
- if (loads > 2)
- printf ("15-minute: %f ", avg[2]);
- if (loads > 0)
- putchar ('\n');
-
- if (naptime == 0)
- break;
- sleep (naptime);
- }
-
- return EXIT_SUCCESS;
-}
-#endif /* TEST */
# Persuade glibc <stdlib.h> to declare getloadavg().
AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
-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/$1/getloadavg.c" ||
AC_MSG_ERROR([$srcdir/$1/getloadavg.c is missing])
gl_save_LIBS=$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
+AC_CHECK_FUNC([getloadavg], [],
+ [gl_have_func=no
+
+ # 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 to test for libelf and libkvm to force the
+ # definition of SVR4 below.
+ if test $gl_have_func = no; then
+ AC_CHECK_LIB([elf], [elf_begin], [LIBS="-lelf $LIBS"])
+ 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])
+ 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 $LIBS" gl_have_func=yes],
+ [LIBS=$gl_getloadavg_LIBS])
+ fi
+
+ # Set up the replacement function if necessary.
+ if test $gl_have_func = no; then
+ AC_LIBOBJ([getloadavg])
+ gl_PREREQ_GETLOADAVG
+ fi])
-# AIX has libperfstat which does not require root
-AC_CHECK_LIB([perfstat], [perfstat_cpu_total])
-test $ac_cv_lib_perfstat_perfstat_cpu_total = 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 to test for libelf and libkvm to force the
-# definition of SVR4 below.
-if test $gl_have_func = no; then
- AC_CHECK_LIB([elf], [elf_begin], [LIBS="-lelf $LIBS"])
- 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 CONFIGURING_GETLOADAVG
-#include "$srcdir/$1/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
# --------------------
# Set up the AC_LIBOBJ replacement of `getloadavg'.
AC_DEFUN([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])])
+
+# 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
+
+# On HPUX9, an unprivileged user can get load averages this way.
+if test $gl_have_func = no; then
+ AC_CHECK_FUNCS([pstat_getdynamic], [gl_have_func=yes])
+fi
+
+# AIX has libperfstat which does not require root
+if test $gl_have_func = no; then
+ AC_CHECK_LIB([perfstat], [perfstat_cpu_total])
+ test $ac_cv_lib_perfstat_perfstat_cpu_total = yes && gl_have_func=yes
+fi
+
+if test $gl_have_func = no; then
+ 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])])
+fi
# 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
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])], [],
+ [], [],
[@%:@include <nlist.h>])
AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <nlist.h>]],
[[struct nlist x;
--- /dev/null
+/* Test of getting load average.
+ Copyright (C) 2011 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 <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include <stdlib.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (getloadavg, int, (double [], int));
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static void
+check_avg (int minutes, double avg, int printit)
+{
+ if (printit)
+ printf ("%d-minute: %f ", minutes, avg);
+ if (avg < 0 || avg != avg)
+ exit (minutes);
+}
+
+/* This program can also be used as a manual test, by invoking it with
+ an argument; it then prints the load average. If the argument is
+ nonzero, the manual test repeats forever, sleeping for the stated
+ interval between each iteration. */
+int
+main (int argc, char **argv)
+{
+ int naptime = 0;
+
+ if (argc > 1)
+ naptime = atoi (argv[1]);
+
+ while (1)
+ {
+ double avg[3];
+ int loads = getloadavg (avg, 3);
+ if (loads == -1)
+ {
+ if (! (errno == ENOSYS || errno == ENOTSUP))
+ return 1;
+ perror ("Skipping test; load average not supported");
+ return 77;
+ }
+ if (loads > 0)
+ check_avg (1, avg[0], argc > 1);
+ if (loads > 1)
+ check_avg (5, avg[1], argc > 1);
+ if (loads > 2)
+ check_avg (15, avg[1], argc > 1);
+ if (loads > 0 && argc > 1)
+ putchar ('\n');
+
+ if (naptime == 0)
+ break;
+ sleep (naptime);
+ }
+
+ return 0;
+}
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