NEWS.stable: log cherry-pick [90a660c]->[e916d00] autoupdate

[gnulib.git] / m4 / getgroups.m4

diff --git a/m4/getgroups.m4 b/m4/getgroups.m4
index 0364752..54dbe8e 100644 (file)
--- a/m4/getgroups.m4
+++ b/m4/getgroups.m4
@@ -1,10 +1,9 @@
-#serial 11
+# serial 16
 
 dnl From Jim Meyering.
 dnl A wrapper around AC_FUNC_GETGROUPS.
 
-# Copyright (C) 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2008 Free
-# Software Foundation, Inc.
+# Copyright (C) 1996-1997, 1999-2004, 2008-2011 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -13,17 +12,29 @@ dnl A wrapper around AC_FUNC_GETGROUPS.
 AC_DEFUN([gl_FUNC_GETGROUPS],
 [
   AC_REQUIRE([AC_FUNC_GETGROUPS])
-  if test "$ac_cv_func_getgroups_works" != yes; then
-    AC_LIBOBJ(getgroups)
-    AC_DEFINE(getgroups, rpl_getgroups,
-      [Define as rpl_getgroups if getgroups doesn't work right.])
-    gl_PREREQ_GETGROUPS
+  AC_REQUIRE([AC_TYPE_GETGROUPS])
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  if test "$ac_cv_func_getgroups" != yes; then
+    HAVE_GETGROUPS=0
+  elif test "$ac_cv_func_getgroups_works.$ac_cv_type_getgroups" != yes.gid_t
+  then
+    REPLACE_GETGROUPS=1
+    AC_DEFINE([GETGROUPS_ZERO_BUG], [1], [Define this to 1 if
+      getgroups(0,NULL) does not return the number of groups.])
+  else
+    dnl Detect FreeBSD bug; POSIX requires getgroups(-1,ptr) to fail.
+    AC_CACHE_CHECK([whether getgroups handles negative values],
+      [gl_cv_func_getgroups_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
+        [[int size = getgroups (0, 0);
+          gid_t *list = malloc (size * sizeof *list);
+          return getgroups (-1, list) != -1;]])],
+        [gl_cv_func_getgroups_works=yes],
+        [gl_cv_func_getgroups_works=no],
+        [gl_cv_func_getgroups_works="guessing no"])])
+    if test "$gl_cv_func_getgroups_works" != yes; then
+      REPLACE_GETGROUPS=1
+    fi
   fi
   test -n "$GETGROUPS_LIB" && LIBS="$GETGROUPS_LIB $LIBS"
 ])
-
-# Prerequisites of lib/getgroups.c.
-AC_DEFUN([gl_PREREQ_GETGROUPS],
-[
-  AC_REQUIRE([AC_TYPE_GETGROUPS])
-])