functions.m4

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# This file is part of Autoconf.			-*- Autoconf -*-
# Checking for functions.
# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 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 2, 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.
#
# As a special exception, the Free Software Foundation gives unlimited
# permission to copy, distribute and modify the configure scripts that
# are the output of Autoconf.  You need not follow the terms of the GNU
# General Public License when using or distributing such scripts, even
# though portions of the text of Autoconf appear in them.  The GNU
# General Public License (GPL) does govern all other use of the material
# that constitutes the Autoconf program.
#
# Certain portions of the Autoconf source text are designed to be copied
# (in certain cases, depending on the input) into the output of
# Autoconf.  We call these the "data" portions.  The rest of the Autoconf
# source text consists of comments plus executable code that decides which
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# the non-data portions to the data portions.)  If your modification has
# such potential, you must delete any notice of this special exception
# to the GPL from your modified version.
#
# Written by David MacKenzie, with help from
# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
# Roland McGrath, Noah Friedman, david d zuhn, and many others.


# Table of contents
#
# 1. Generic tests for functions.
# 2. Functions to check with AC_CHECK_FUNCS
# 3. Tests for specific functions.


## -------------------------------- ##
## 1. Generic tests for functions.  ##
## -------------------------------- ##


# AC_CHECK_FUNC(FUNCTION, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
# -----------------------------------------------------------------
AC_DEFUN([AC_CHECK_FUNC],
[AS_VAR_PUSHDEF([ac_var], [ac_cv_func_$1])dnl
AC_CACHE_CHECK([for $1], ac_var,
[AC_LINK_IFELSE([AC_LANG_FUNC_LINK_TRY([$1])],
		[AS_VAR_SET(ac_var, yes)],
		[AS_VAR_SET(ac_var, no)])])
AS_IF([test AS_VAR_GET(ac_var) = yes], [$2], [$3])dnl
AS_VAR_POPDEF([ac_var])dnl
])# AC_CHECK_FUNC


# _AH_CHECK_FUNCS(FUNCTION...)
# ----------------------------
m4_define([_AH_CHECK_FUNCS],
[m4_foreach_w([AC_Func], [$1],
   [AH_TEMPLATE(AS_TR_CPP([HAVE_]m4_defn([AC_Func])),
      [Define to 1 if you have the `]m4_defn([AC_Func])[' function.])])])


# AC_CHECK_FUNCS(FUNCTION..., [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
# ---------------------------------------------------------------------
AC_DEFUN([AC_CHECK_FUNCS],
[_AH_CHECK_FUNCS([$1])dnl
for ac_func in $1
do
AC_CHECK_FUNC($ac_func,
	      [AC_DEFINE_UNQUOTED([AS_TR_CPP([HAVE_$ac_func])]) $2],
	      [$3])dnl
done
])


# AC_CHECK_FUNCS_ONCE(FUNCTION...)
# --------------------------------
AC_DEFUN([AC_CHECK_FUNCS_ONCE],
[
  _AH_CHECK_FUNCS([$1])
  m4_foreach_w([AC_Func], [$1],
    [AC_DEFUN([_AC_Func_]m4_defn([AC_Func]),
       [m4_divert_text([INIT_PREPARE],
	  [ac_func_list="$ac_func_list AC_Func"])
	_AC_FUNCS_EXPANSION])
     AC_REQUIRE([_AC_Func_]m4_defn([AC_Func]))])
])
m4_define([_AC_FUNCS_EXPANSION],
[
  m4_divert_text([DEFAULTS], [ac_func_list=])
  AC_CHECK_FUNCS([$ac_func_list])
  m4_define([_AC_FUNCS_EXPANSION], [])
])


# AC_REPLACE_FUNCS(FUNCTION...)
# -----------------------------
AC_DEFUN([AC_REPLACE_FUNCS],
[m4_foreach_w([AC_Func], [$1], [AC_LIBSOURCE(AC_Func.c)])dnl
AC_CHECK_FUNCS([$1], , [_AC_LIBOBJ($ac_func)])
])


# AC_TRY_LINK_FUNC(FUNC, ACTION-IF-FOUND, ACTION-IF-NOT-FOUND)
# ------------------------------------------------------------
# Try to link a program that calls FUNC, handling GCC builtins.  If
# the link succeeds, execute ACTION-IF-FOUND; otherwise, execute
# ACTION-IF-NOT-FOUND.
AC_DEFUN([AC_TRY_LINK_FUNC],
[AC_LINK_IFELSE([AC_LANG_CALL([], [$1])], [$2], [$3])])


# AU::AC_FUNC_CHECK
# -----------------
AU_ALIAS([AC_FUNC_CHECK], [AC_CHECK_FUNC])


# AU::AC_HAVE_FUNCS
# -----------------
AU_ALIAS([AC_HAVE_FUNCS], [AC_CHECK_FUNCS])




## ------------------------------------------- ##
## 2. Functions to check with AC_CHECK_FUNCS.  ##
## ------------------------------------------- ##

AN_FUNCTION([__argz_count],            [AC_CHECK_FUNCS])
AN_FUNCTION([__argz_next],             [AC_CHECK_FUNCS])
AN_FUNCTION([__argz_stringify],        [AC_CHECK_FUNCS])
AN_FUNCTION([__fpending],              [AC_CHECK_FUNCS])
AN_FUNCTION([acl],                     [AC_CHECK_FUNCS])
AN_FUNCTION([alarm],                   [AC_CHECK_FUNCS])
AN_FUNCTION([atexit],                  [AC_CHECK_FUNCS])
AN_FUNCTION([btowc],                   [AC_CHECK_FUNCS])
AN_FUNCTION([bzero],                   [AC_CHECK_FUNCS])
AN_FUNCTION([clock_gettime],           [AC_CHECK_FUNCS])
AN_FUNCTION([doprnt],                  [AC_CHECK_FUNCS])
AN_FUNCTION([dup2],                    [AC_CHECK_FUNCS])
AN_FUNCTION([endgrent],                [AC_CHECK_FUNCS])
AN_FUNCTION([endpwent],                [AC_CHECK_FUNCS])
AN_FUNCTION([euidaccess],              [AC_CHECK_FUNCS])
AN_FUNCTION([fchdir],                  [AC_CHECK_FUNCS])
AN_FUNCTION([fdatasync],               [AC_CHECK_FUNCS])
AN_FUNCTION([fesetround],              [AC_CHECK_FUNCS])
AN_FUNCTION([floor],                   [AC_CHECK_FUNCS])
AN_FUNCTION([fs_stat_dev],             [AC_CHECK_FUNCS])
AN_FUNCTION([ftime],                   [AC_CHECK_FUNCS])
AN_FUNCTION([ftruncate],               [AC_CHECK_FUNCS])
AN_FUNCTION([getcwd],                  [AC_CHECK_FUNCS])
AN_FUNCTION([getdelim],                [AC_CHECK_FUNCS])
AN_FUNCTION([gethostbyaddr],           [AC_CHECK_FUNCS])
AN_FUNCTION([gethostbyname],           [AC_CHECK_FUNCS])
AN_FUNCTION([gethostname],             [AC_CHECK_FUNCS])
AN_FUNCTION([gethrtime],               [AC_CHECK_FUNCS])
AN_FUNCTION([getmntent],               [AC_CHECK_FUNCS])
AN_FUNCTION([getmntinfo],              [AC_CHECK_FUNCS])
AN_FUNCTION([getpagesize],             [AC_CHECK_FUNCS])
AN_FUNCTION([getpass],                 [AC_CHECK_FUNCS])
AN_FUNCTION([getspnam],                [AC_CHECK_FUNCS])
AN_FUNCTION([gettimeofday],            [AC_CHECK_FUNCS])
AN_FUNCTION([getusershell],            [AC_CHECK_FUNCS])
AN_FUNCTION([hasmntopt],               [AC_CHECK_FUNCS])
AN_FUNCTION([inet_ntoa],               [AC_CHECK_FUNCS])
AN_FUNCTION([isascii],                 [AC_CHECK_FUNCS])
AN_FUNCTION([iswprint],                [AC_CHECK_FUNCS])
AN_FUNCTION([lchown],                  [AC_CHECK_FUNCS])
AN_FUNCTION([listmntent],              [AC_CHECK_FUNCS])
AN_FUNCTION([localeconv],              [AC_CHECK_FUNCS])
AN_FUNCTION([localtime_r],             [AC_CHECK_FUNCS])
AN_FUNCTION([mblen],                   [AC_CHECK_FUNCS])
AN_FUNCTION([mbrlen],                  [AC_CHECK_FUNCS])
AN_FUNCTION([memchr],                  [AC_CHECK_FUNCS])
AN_FUNCTION([memmove],                 [AC_CHECK_FUNCS])
AN_FUNCTION([mempcpy],                 [AC_CHECK_FUNCS])
AN_FUNCTION([memset],                  [AC_CHECK_FUNCS])
AN_FUNCTION([mkdir],                   [AC_CHECK_FUNCS])
AN_FUNCTION([mkfifo],                  [AC_CHECK_FUNCS])
AN_FUNCTION([modf],                    [AC_CHECK_FUNCS])
AN_FUNCTION([munmap],                  [AC_CHECK_FUNCS])
AN_FUNCTION([next_dev],                [AC_CHECK_FUNCS])
AN_FUNCTION([nl_langinfo],             [AC_CHECK_FUNCS])
AN_FUNCTION([pathconf],                [AC_CHECK_FUNCS])
AN_FUNCTION([pow],                     [AC_CHECK_FUNCS])
AN_FUNCTION([pstat_getdynamic],        [AC_CHECK_FUNCS])
AN_FUNCTION([putenv],                  [AC_CHECK_FUNCS])
AN_FUNCTION([re_comp],                 [AC_CHECK_FUNCS])
AN_FUNCTION([realpath],                [AC_CHECK_FUNCS])
AN_FUNCTION([regcmp],                  [AC_CHECK_FUNCS])
AN_FUNCTION([regcomp],                 [AC_CHECK_FUNCS])
AN_FUNCTION([resolvepath],             [AC_CHECK_FUNCS])
AN_FUNCTION([rint],                    [AC_CHECK_FUNCS])
AN_FUNCTION([rmdir],                   [AC_CHECK_FUNCS])
AN_FUNCTION([rpmatch],                 [AC_CHECK_FUNCS])
AN_FUNCTION([select],                  [AC_CHECK_FUNCS])
AN_FUNCTION([setenv],                  [AC_CHECK_FUNCS])
AN_FUNCTION([sethostname],             [AC_CHECK_FUNCS])
AN_FUNCTION([setlocale],               [AC_CHECK_FUNCS])
AN_FUNCTION([socket],                  [AC_CHECK_FUNCS])
AN_FUNCTION([sqrt],                    [AC_CHECK_FUNCS])
AN_FUNCTION([stime],                   [AC_CHECK_FUNCS])
AN_FUNCTION([stpcpy],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strcasecmp],              [AC_CHECK_FUNCS])
AN_FUNCTION([strchr],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strcspn],                 [AC_CHECK_FUNCS])
AN_FUNCTION([strdup],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strerror],                [AC_CHECK_FUNCS])
AN_FUNCTION([strncasecmp],             [AC_CHECK_FUNCS])
AN_FUNCTION([strndup],                 [AC_CHECK_FUNCS])
AN_FUNCTION([strpbrk],                 [AC_CHECK_FUNCS])
AN_FUNCTION([strrchr],                 [AC_CHECK_FUNCS])
AN_FUNCTION([strspn],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strstr],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strtol],                  [AC_CHECK_FUNCS])
AN_FUNCTION([strtoul],                 [AC_CHECK_FUNCS])
AN_FUNCTION([strtoull],                [AC_CHECK_FUNCS])
AN_FUNCTION([strtoumax],               [AC_CHECK_FUNCS])
AN_FUNCTION([strverscmp],              [AC_CHECK_FUNCS])
AN_FUNCTION([sysinfo],                 [AC_CHECK_FUNCS])
AN_FUNCTION([tzset],                   [AC_CHECK_FUNCS])
AN_FUNCTION([uname],                   [AC_CHECK_FUNCS])
AN_FUNCTION([utime],                   [AC_CHECK_FUNCS])
AN_FUNCTION([utmpname],                [AC_CHECK_FUNCS])
AN_FUNCTION([utmpxname],               [AC_CHECK_FUNCS])
AN_FUNCTION([wcwidth],                 [AC_CHECK_FUNCS])


AN_FUNCTION([dcgettext],    [AM_GNU_GETTEXT])
AN_FUNCTION([getwd],        [warn: getwd is deprecated, use getcwd instead])


## --------------------------------- ##
## 3. Tests for specific functions.  ##
## --------------------------------- ##


# The macros are sorted:
#
# 1. AC_FUNC_* macros are sorted by alphabetical order.
#
# 2. Helping macros such as _AC_LIBOBJ_* are before the macro that
#    uses it.
#
# 3. Obsolete macros are right after the modern macro.



# _AC_LIBOBJ_ALLOCA
# -----------------
# Set up the LIBOBJ replacement of `alloca'.  Well, not exactly
# AC_LIBOBJ since we actually set the output variable `ALLOCA'.
# Nevertheless, for Automake, AC_LIBSOURCES it.
m4_define([_AC_LIBOBJ_ALLOCA],
[# The SVR3 libPW and SVR4 libucb both contain incompatible functions
# that cause trouble.  Some versions do not even contain alloca or
# contain a buggy version.  If you still want to use their alloca,
# use ar to extract alloca.o from them instead of compiling alloca.c.
AC_LIBSOURCES(alloca.c)
AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.$ac_objext])dnl
AC_DEFINE(C_ALLOCA, 1, [Define to 1 if using `alloca.c'.])

AC_CACHE_CHECK(whether `alloca.c' needs Cray hooks, ac_cv_os_cray,
[AC_EGREP_CPP(webecray,
[#if defined CRAY && ! defined CRAY2
webecray
#else
wenotbecray
#endif
], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
if test $ac_cv_os_cray = yes; then
  for ac_func in _getb67 GETB67 getb67; do
    AC_CHECK_FUNC($ac_func,
		  [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func,
				      [Define to one of `_getb67', `GETB67',
				       `getb67' for Cray-2 and Cray-YMP
				       systems. This function is required for
				       `alloca.c' support on those systems.])
    break])
  done
fi

AC_CACHE_CHECK([stack direction for C alloca],
	       [ac_cv_c_stack_direction],
[AC_RUN_IFELSE([AC_LANG_SOURCE(
[AC_INCLUDES_DEFAULT
int
find_stack_direction ()
{
  static char *addr = 0;
  auto char dummy;
  if (addr == 0)
    {
      addr = &dummy;
      return find_stack_direction ();
    }
  else
    return (&dummy > addr) ? 1 : -1;
}

int
main ()
{
  return find_stack_direction () < 0;
}])],
	       [ac_cv_c_stack_direction=1],
	       [ac_cv_c_stack_direction=-1],
	       [ac_cv_c_stack_direction=0])])
AH_VERBATIM([STACK_DIRECTION],
[/* If using the C implementation of alloca, define if you know the
   direction of stack growth for your system; otherwise it will be
   automatically deduced at runtime.
	STACK_DIRECTION > 0 => grows toward higher addresses
	STACK_DIRECTION < 0 => grows toward lower addresses
	STACK_DIRECTION = 0 => direction of growth unknown */
@%:@undef STACK_DIRECTION])dnl
AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction)
])# _AC_LIBOBJ_ALLOCA


# AC_FUNC_ALLOCA
# --------------
AN_FUNCTION([alloca], [AC_FUNC_ALLOCA])
AN_HEADER([alloca.h], [AC_FUNC_ALLOCA])
AC_DEFUN([AC_FUNC_ALLOCA],
[# The Ultrix 4.2 mips builtin alloca declared by alloca.h only works
# for constant arguments.  Useless!
AC_CACHE_CHECK([for working alloca.h], ac_cv_working_alloca_h,
[AC_LINK_IFELSE(
       [AC_LANG_PROGRAM([[@%:@include <alloca.h>]],
			[[char *p = (char *) alloca (2 * sizeof (int));
			  if (p) return 0;]])],
		[ac_cv_working_alloca_h=yes],
		[ac_cv_working_alloca_h=no])])
if test $ac_cv_working_alloca_h = yes; then
  AC_DEFINE(HAVE_ALLOCA_H, 1,
	    [Define to 1 if you have <alloca.h> and it should be used
	     (not on Ultrix).])
fi

AC_CACHE_CHECK([for alloca], ac_cv_func_alloca_works,
[AC_LINK_IFELSE([AC_LANG_PROGRAM(
[[#ifdef __GNUC__
# define alloca __builtin_alloca
#else
# ifdef _MSC_VER
#  include <malloc.h>
#  define alloca _alloca
# else
#  if HAVE_ALLOCA_H
#   include <alloca.h>
#  else
#   ifdef _AIX
 #pragma alloca
#   else
#    ifndef alloca /* predefined by HP cc +Olibcalls */
char *alloca ();
#    endif
#   endif
#  endif
# endif
#endif
]],                               [[char *p = (char *) alloca (1);
				    if (p) return 0;]])],
		[ac_cv_func_alloca_works=yes],
		[ac_cv_func_alloca_works=no])])

if test $ac_cv_func_alloca_works = yes; then
  AC_DEFINE(HAVE_ALLOCA, 1,
	    [Define to 1 if you have `alloca', as a function or macro.])
else
  _AC_LIBOBJ_ALLOCA
fi
])# AC_FUNC_ALLOCA


# AU::AC_ALLOCA
# -------------
AU_ALIAS([AC_ALLOCA], [AC_FUNC_ALLOCA])