code.delx.au - gnu-emacs/blob - m4/getgroups.m4

   1 # serial 18
   2
   3 dnl From Jim Meyering.
   4 dnl A wrapper around AC_FUNC_GETGROUPS.
   5
   6 # Copyright (C) 1996-1997, 1999-2004, 2008-2015 Free Software
   7 # Foundation, Inc.
   8 #
   9 # This file is free software; the Free Software Foundation
  10 # gives unlimited permission to copy and/or distribute it,
  11 # with or without modifications, as long as this notice is preserved.
  12
  13 m4_version_prereq([2.70], [] ,[
  14
  15 # This is taken from the following Autoconf patch:
  16 # http://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=commitdiff;h=7fbb553727ed7e0e689a17594b58559ecf3ea6e9
  17 AC_DEFUN([AC_FUNC_GETGROUPS],
  18 [
  19   AC_REQUIRE([AC_TYPE_GETGROUPS])dnl
  20   AC_REQUIRE([AC_TYPE_SIZE_T])dnl
  21   AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles
  22   AC_CHECK_FUNC([getgroups])
  23
  24   # If we don't yet have getgroups, see if it's in -lbsd.
  25   # This is reported to be necessary on an ITOS 3000WS running SEIUX 3.1.
  26   ac_save_LIBS=$LIBS
  27   if test $ac_cv_func_getgroups = no; then
  28     AC_CHECK_LIB(bsd, getgroups, [GETGROUPS_LIB=-lbsd])
  29   fi
  30
  31   # Run the program to test the functionality of the system-supplied
  32   # getgroups function only if there is such a function.
  33   if test $ac_cv_func_getgroups = yes; then
  34     AC_CACHE_CHECK([for working getgroups], [ac_cv_func_getgroups_works],
  35       [AC_RUN_IFELSE(
  36          [AC_LANG_PROGRAM(
  37             [AC_INCLUDES_DEFAULT],
  38             [[/* On Ultrix 4.3, getgroups (0, 0) always fails.  */
  39               return getgroups (0, 0) == -1;]])
  40          ],
  41          [ac_cv_func_getgroups_works=yes],
  42          [ac_cv_func_getgroups_works=no],
  43          [case "$host_os" in # ((
  44                     # Guess yes on glibc systems.
  45             *-gnu*) ac_cv_func_getgroups_works="guessing yes" ;;
  46                     # If we don't know, assume the worst.
  47             *)      ac_cv_func_getgroups_works="guessing no" ;;
  48           esac
  49          ])
  50       ])
  51   else
  52     ac_cv_func_getgroups_works=no
  53   fi
  54   case "$ac_cv_func_getgroups_works" in
  55     *yes)
  56       AC_DEFINE([HAVE_GETGROUPS], [1],
  57         [Define to 1 if your system has a working `getgroups' function.])
  58       ;;
  59   esac
  60   LIBS=$ac_save_LIBS
  61 ])# AC_FUNC_GETGROUPS
  62
  63 ])
  64
  65 AC_DEFUN([gl_FUNC_GETGROUPS],
  66 [
  67   AC_REQUIRE([AC_TYPE_GETGROUPS])
  68   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
  69   AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
  70
  71   AC_FUNC_GETGROUPS
  72   if test $ac_cv_func_getgroups != yes; then
  73     HAVE_GETGROUPS=0
  74   else
  75     if test "$ac_cv_type_getgroups" != gid_t \
  76        || { case "$ac_cv_func_getgroups_works" in
  77               *yes) false;;
  78               *) true;;
  79             esac
  80           }; then
  81       REPLACE_GETGROUPS=1
  82       AC_DEFINE([GETGROUPS_ZERO_BUG], [1], [Define this to 1 if
  83         getgroups(0,NULL) does not return the number of groups.])
  84     else
  85       dnl Detect FreeBSD bug; POSIX requires getgroups(-1,ptr) to fail.
  86       AC_CACHE_CHECK([whether getgroups handles negative values],
  87         [gl_cv_func_getgroups_works],
  88         [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
  89           [[int size = getgroups (0, 0);
  90             gid_t *list = malloc (size * sizeof *list);
  91             return getgroups (-1, list) != -1;]])],
  92           [gl_cv_func_getgroups_works=yes],
  93           [gl_cv_func_getgroups_works=no],
  94           [case "$host_os" in
  95                      # Guess yes on glibc systems.
  96              *-gnu*) gl_cv_func_getgroups_works="guessing yes" ;;
  97                      # If we don't know, assume the worst.
  98              *)      gl_cv_func_getgroups_works="guessing no" ;;
  99            esac
 100           ])])
 101       case "$gl_cv_func_getgroups_works" in
 102         *yes) ;;
 103         *) REPLACE_GETGROUPS=1 ;;
 104       esac
 105     fi
 106   fi
 107   test -n "$GETGROUPS_LIB" && LIBS="$GETGROUPS_LIB $LIBS"
 108 ])