third_party/talloc/libreplace/libreplace_macros.m4 - chromium/src - Git at Google

 #
 # This is a collection of useful autoconf macros
 #

 ############################################
 # Check if the compiler handles c99 struct initialization, and if not try -AC99 and -c99 flags
 # Usage: LIBREPLACE_C99_STRUCT_INIT(success-action,failure-action)
 # changes CFLAGS to add -AC99 or -c99 if needed
 AC_DEFUN([LIBREPLACE_C99_STRUCT_INIT],
 [
 saved_CFLAGS="$CFLAGS";
 c99_init=no
 if test x"$c99_init" = x"no"; then
     AC_MSG_CHECKING(for C99 designated initializers)
     CFLAGS="$saved_CFLAGS";
     AC_TRY_COMPILE([#include <stdio.h>],
      [ struct foo {int x;char y;};
        struct foo bar = { .y = 'X', .x = 1 };
      ],
      [AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
 fi
 if test x"$c99_init" = x"no"; then
     AC_MSG_CHECKING(for C99 designated initializers with -AC99)
     CFLAGS="$saved_CFLAGS -AC99";
     AC_TRY_COMPILE([#include <stdio.h>],
      [ struct foo {int x;char y;};
        struct foo bar = { .y = 'X', .x = 1 };
      ],
      [AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
 fi
 if test x"$c99_init" = x"no"; then
     AC_MSG_CHECKING(for C99 designated initializers with -qlanglvl=extc99)
     CFLAGS="$saved_CFLAGS -qlanglvl=extc99";
     AC_TRY_COMPILE([#include <stdio.h>],
      [ struct foo {int x;char y;};
        struct foo bar = { .y = 'X', .x = 1 };
      ],
      [AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
 fi
 if test x"$c99_init" = x"no"; then
     AC_MSG_CHECKING(for C99 designated initializers with -qlanglvl=stdc99)
     CFLAGS="$saved_CFLAGS -qlanglvl=stdc99";
     AC_TRY_COMPILE([#include <stdio.h>],
      [ struct foo {int x;char y;};
        struct foo bar = { .y = 'X', .x = 1 };
      ],
      [AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
 fi
 if test x"$c99_init" = x"no"; then
     AC_MSG_CHECKING(for C99 designated initializers with -c99)
     CFLAGS="$saved_CFLAGS -c99"
     AC_TRY_COMPILE([#include <stdio.h>],
      [ struct foo {int x;char y;};
        struct foo bar = { .y = 'X', .x = 1 };
      ],
      [AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
 fi

 if test "`uname`" = "HP-UX"; then
   if test "$ac_cv_c_compiler_gnu" = no; then
 	# special override for broken HP-UX compiler - I can't find a way to test
 	# this properly (its a compiler bug)
 	CFLAGS="$CFLAGS -AC99";
 	c99_init=yes;
   fi
 fi

 if test x"$c99_init" = x"yes"; then
     saved_CFLAGS=""
     $1
 else
     CFLAGS="$saved_CFLAGS"
     saved_CFLAGS=""
     $2
 fi
 ])

 dnl AC_PROG_CC_FLAG(flag)
 AC_DEFUN(AC_PROG_CC_FLAG,
 [AC_CACHE_CHECK(whether ${CC-cc} accepts -$1, ac_cv_prog_cc_$1,
 [echo 'void f(){}' > conftest.c
 if test -z "`${CC-cc} -$1 -c conftest.c 2>&1`"; then
   ac_cv_prog_cc_$1=yes
 else
   ac_cv_prog_cc_$1=no
 fi
 rm -f conftest*
 ])])

 dnl see if a declaration exists for a function or variable
 dnl defines HAVE_function_DECL if it exists
 dnl AC_HAVE_DECL(var, includes)
 AC_DEFUN(AC_HAVE_DECL,
 [
  AC_CACHE_CHECK([for $1 declaration],ac_cv_have_$1_decl,[
     AC_TRY_COMPILE([$2],[int i = (int)$1],
         ac_cv_have_$1_decl=yes,ac_cv_have_$1_decl=no)])
  if test x"$ac_cv_have_$1_decl" = x"yes"; then
     AC_DEFINE([HAVE_]translit([$1], [a-z], [A-Z])[_DECL],1,[Whether $1() is available])
  fi
 ])


 # AC_CHECK_LIB_EXT(LIBRARY, [EXT_LIBS], [FUNCTION],
 #              [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
 #              [ADD-ACTION-IF-FOUND],[OTHER-LIBRARIES])
 # ------------------------------------------------------
 #
 # Use a cache variable name containing both the library and function name,
 # because the test really is for library $1 defining function $3, not
 # just for library $1.  Separate tests with the same $1 and different $3s
 # may have different results.
 #
 # Note that using directly AS_VAR_PUSHDEF([ac_Lib], [ac_cv_lib_$1_$3])
 # is asking for trouble, since AC_CHECK_LIB($lib, fun) would give
 # ac_cv_lib_$lib_fun, which is definitely not what was meant.  Hence
 # the AS_LITERAL_IF indirection.
 #
 # FIXME: This macro is extremely suspicious.  It DEFINEs unconditionally,
 # whatever the FUNCTION, in addition to not being a *S macro.  Note
 # that the cache does depend upon the function we are looking for.
 #
 # It is on purpose we used `ac_check_lib_ext_save_LIBS' and not just
 # `ac_save_LIBS': there are many macros which don't want to see `LIBS'
 # changed but still want to use AC_CHECK_LIB_EXT, so they save `LIBS'.
 # And ``ac_save_LIBS' is too tempting a name, so let's leave them some
 # freedom.
 AC_DEFUN([AC_CHECK_LIB_EXT],
 [
 AH_CHECK_LIB_EXT([$1])
 ac_check_lib_ext_save_LIBS=$LIBS
 LIBS="-l$1 $$2 $7 $LIBS"
 AS_LITERAL_IF([$1],
       [AS_VAR_PUSHDEF([ac_Lib_ext], [ac_cv_lib_ext_$1])],
       [AS_VAR_PUSHDEF([ac_Lib_ext], [ac_cv_lib_ext_$1''])])dnl

 m4_ifval([$3],
  [
     AH_CHECK_FUNC_EXT([$3])
     AS_LITERAL_IF([$1],
               [AS_VAR_PUSHDEF([ac_Lib_func], [ac_cv_lib_ext_$1_$3])],
               [AS_VAR_PUSHDEF([ac_Lib_func], [ac_cv_lib_ext_$1''_$3])])dnl
     AC_CACHE_CHECK([for $3 in -l$1], ac_Lib_func,
 	[AC_TRY_LINK_FUNC($3,
                  [AS_VAR_SET(ac_Lib_func, yes);
 		  AS_VAR_SET(ac_Lib_ext, yes)],
                  [AS_VAR_SET(ac_Lib_func, no);
 		  AS_VAR_SET(ac_Lib_ext, no)])
 	])
     AS_IF([test AS_VAR_GET(ac_Lib_func) = yes],
         [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_$3))])dnl
     AS_VAR_POPDEF([ac_Lib_func])dnl
  ],[
     AC_CACHE_CHECK([for -l$1], ac_Lib_ext,
 	[AC_TRY_LINK_FUNC([main],
                  [AS_VAR_SET(ac_Lib_ext, yes)],
                  [AS_VAR_SET(ac_Lib_ext, no)])
 	])
  ])
 LIBS=$ac_check_lib_ext_save_LIBS

 AS_IF([test AS_VAR_GET(ac_Lib_ext) = yes],
     [m4_default([$4],
         [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_LIB$1))
 		case "$$2" in
 		    *-l$1*)
 			;;
 		    *)
 			$2="-l$1 $$2"
 			;;
 		esac])
 		[$6]
 	    ],
 	    [$5])dnl
 AS_VAR_POPDEF([ac_Lib_ext])dnl
 ])# AC_CHECK_LIB_EXT

 # AH_CHECK_LIB_EXT(LIBNAME)
 # ---------------------
 m4_define([AH_CHECK_LIB_EXT],
 [AH_TEMPLATE(AS_TR_CPP(HAVE_LIB$1),
              [Define to 1 if you have the `]$1[' library (-l]$1[).])])

 dnl AC_SEARCH_LIBS_EXT(FUNCTION, SEARCH-LIBS, EXT_LIBS,
 dnl                    [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
 dnl                    [OTHER-LIBRARIES])
 dnl --------------------------------------------------------
 dnl Search for a library defining FUNC, if it's not already available.
 AC_DEFUN([AC_SEARCH_LIBS_EXT],
 [AC_CACHE_CHECK([for library containing $1], [ac_cv_search_ext_$1],
 [
 ac_func_search_ext_save_LIBS=$LIBS
 ac_cv_search_ext_$1=no
 AC_LINK_IFELSE([AC_LANG_CALL([], [$1])],
 	       [ac_cv_search_ext_$1="none required"])
 if test "$ac_cv_search_ext_$1" = no; then
   for ac_lib in $2; do
     LIBS="-l$ac_lib $$3 $6 $ac_func_search_save_ext_LIBS"
     AC_LINK_IFELSE([AC_LANG_CALL([], [$1])],
 		   [ac_cv_search_ext_$1="-l$ac_lib"
 break])
   done
 fi
 LIBS=$ac_func_search_ext_save_LIBS])
 AS_IF([test "$ac_cv_search_ext_$1" != no],
   [test "$ac_cv_search_ext_$1" = "none required" || $3="$ac_cv_search_ext_$1 $$3"
   $4],
       [$5])dnl
 ])

 dnl check for a function in a $LIBS and $OTHER_LIBS libraries variable.
 dnl AC_CHECK_FUNC_EXT(func,OTHER_LIBS,IF-TRUE,IF-FALSE)
 AC_DEFUN([AC_CHECK_FUNC_EXT],
 [
     AH_CHECK_FUNC_EXT($1)
     ac_check_func_ext_save_LIBS=$LIBS
     LIBS="$2 $LIBS"
     AS_VAR_PUSHDEF([ac_var], [ac_cv_func_ext_$1])dnl
     AC_CACHE_CHECK([for $1], ac_var,
 	[AC_LINK_IFELSE([AC_LANG_FUNC_LINK_TRY([$1])],
                 [AS_VAR_SET(ac_var, yes)],
                 [AS_VAR_SET(ac_var, no)])])
     LIBS=$ac_check_func_ext_save_LIBS
     AS_IF([test AS_VAR_GET(ac_var) = yes],
 	    [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_$1])) $3],
 	    [$4])dnl
 AS_VAR_POPDEF([ac_var])dnl
 ])# AC_CHECK_FUNC

 # AH_CHECK_FUNC_EXT(FUNCNAME)
 # ---------------------
 m4_define([AH_CHECK_FUNC_EXT],
 [AH_TEMPLATE(AS_TR_CPP(HAVE_$1),
              [Define to 1 if you have the `]$1[' function.])])

 dnl Define an AC_DEFINE with ifndef guard.
 dnl AC_N_DEFINE(VARIABLE [, VALUE])
 AC_DEFUN([AC_N_DEFINE],
 [
 AH_VERBATIM([$1], [
 #ifndef $1
 # undef $1
 #endif
 ])

  cat >>confdefs.h <<\EOF
 #ifndef $1
 [#define] $1 m4_if($#, 1, 1, [$2])
 #endif
 EOF
 ])

 dnl Add an #include
 dnl AC_ADD_INCLUDE(VARIABLE)
 define(AC_ADD_INCLUDE,
 [cat >> confdefs.h <<\EOF
 [#include] $1
 EOF
 ])

 dnl remove an #include
 dnl AC_REMOVE_INCLUDE(VARIABLE)
 define(AC_REMOVE_INCLUDE,
 [
 grep -v '[#include] $1' confdefs.h >confdefs.h.tmp
 cat confdefs.h.tmp > confdefs.h
 rm confdefs.h.tmp
 ])

 dnl remove an #define
 dnl AC_REMOVE_DEFINE(VARIABLE)
 define(AC_REMOVE_DEFINE,
 [
 grep -v '[#define] $1 ' confdefs.h |grep -v '[#define] $1[$]'>confdefs.h.tmp
 cat confdefs.h.tmp > confdefs.h
 rm confdefs.h.tmp
 ])

 dnl AS_HELP_STRING is not available in autoconf 2.57, and AC_HELP_STRING is deprecated
 dnl in autoconf 2.59, so define AS_HELP_STRING to be AC_HELP_STRING unless it is already
 dnl defined.
 m4_ifdef([AS_HELP_STRING], , [m4_define([AS_HELP_STRING], m4_defn([AC_HELP_STRING]))])

 dnl check if the prototype in the header matches the given one
 dnl AC_VERIFY_C_PROTOTYPE(prototype,functionbody,[IF-TRUE].[IF-FALSE],[extraheaders])
 AC_DEFUN(AC_VERIFY_C_PROTOTYPE,
 [AC_CACHE_CHECK([for prototype $1], AS_TR_SH([ac_cv_c_prototype_$1]),
 	AC_COMPILE_IFELSE([AC_LANG_SOURCE([
 		AC_INCLUDES_DEFAULT
 		$5
 		$1
 		{
 			$2
 		}
 	])],[
 		AS_TR_SH([ac_cv_c_prototype_$1])=yes
 	],[
 		AS_TR_SH([ac_cv_c_prototype_$1])=no
 	])
 )
 AS_IF([test $AS_TR_SH([ac_cv_c_prototype_$1]) = yes],[$3],[$4])
 ])

 AC_DEFUN(LIBREPLACE_PROVIDE_HEADER,
 [AC_CHECK_HEADER([$1],
 		[ AC_CONFIG_COMMANDS(rm-$1, [rm -f $libreplacedir/$1], [libreplacedir=$libreplacedir]) ],
 		[ AC_CONFIG_COMMANDS(mk-$1, [echo "#include \"replace.h\"" > $libreplacedir/$1], [libreplacedir=$libreplacedir]) ]
 	)
 ])

 dnl AC_HAVE_TYPE(TYPE,INCLUDES)
 AC_DEFUN([AC_HAVE_TYPE], [
 AC_REQUIRE([AC_HEADER_STDC])
 cv=`echo "$1" | sed 'y%./+- %__p__%'`
 AC_MSG_CHECKING(for $1)
 AC_CACHE_VAL([ac_cv_type_$cv],
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 AC_INCLUDES_DEFAULT
 $2]],
 [[$1 foo;]])],
 [eval "ac_cv_type_$cv=yes"],
 [eval "ac_cv_type_$cv=no"]))dnl
 ac_foo=`eval echo \\$ac_cv_type_$cv`
 AC_MSG_RESULT($ac_foo)
 if test "$ac_foo" = yes; then
   ac_tr_hdr=HAVE_`echo $1 | sed 'y%abcdefghijklmnopqrstuvwxyz./- %ABCDEFGHIJKLMNOPQRSTUVWXYZ____%'`
 if false; then
 	AC_CHECK_TYPES($1)
 fi
   AC_DEFINE_UNQUOTED($ac_tr_hdr, 1, [Define if you have type `$1'])
 fi
 ])
	#
	# This is a collection of useful autoconf macros
	#

	############################################
	# Check if the compiler handles c99 struct initialization, and if not try -AC99 and -c99 flags
	# Usage: LIBREPLACE_C99_STRUCT_INIT(success-action,failure-action)
	# changes CFLAGS to add -AC99 or -c99 if needed
	AC_DEFUN([LIBREPLACE_C99_STRUCT_INIT],
	[
	saved_CFLAGS="$CFLAGS";
	c99_init=no
	if test x"$c99_init" = x"no"; then
	AC_MSG_CHECKING(for C99 designated initializers)
	CFLAGS="$saved_CFLAGS";
	AC_TRY_COMPILE([#include <stdio.h>],
	[ struct foo {int x;char y;};
	struct foo bar = { .y = 'X', .x = 1 };
	],
	[AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
	fi
	if test x"$c99_init" = x"no"; then
	AC_MSG_CHECKING(for C99 designated initializers with -AC99)
	CFLAGS="$saved_CFLAGS -AC99";
	AC_TRY_COMPILE([#include <stdio.h>],
	[ struct foo {int x;char y;};
	struct foo bar = { .y = 'X', .x = 1 };
	],
	[AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
	fi
	if test x"$c99_init" = x"no"; then
	AC_MSG_CHECKING(for C99 designated initializers with -qlanglvl=extc99)
	CFLAGS="$saved_CFLAGS -qlanglvl=extc99";
	AC_TRY_COMPILE([#include <stdio.h>],
	[ struct foo {int x;char y;};
	struct foo bar = { .y = 'X', .x = 1 };
	],
	[AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
	fi
	if test x"$c99_init" = x"no"; then
	AC_MSG_CHECKING(for C99 designated initializers with -qlanglvl=stdc99)
	CFLAGS="$saved_CFLAGS -qlanglvl=stdc99";
	AC_TRY_COMPILE([#include <stdio.h>],
	[ struct foo {int x;char y;};
	struct foo bar = { .y = 'X', .x = 1 };
	],
	[AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
	fi
	if test x"$c99_init" = x"no"; then
	AC_MSG_CHECKING(for C99 designated initializers with -c99)
	CFLAGS="$saved_CFLAGS -c99"
	AC_TRY_COMPILE([#include <stdio.h>],
	[ struct foo {int x;char y;};
	struct foo bar = { .y = 'X', .x = 1 };
	],
	[AC_MSG_RESULT(yes); c99_init=yes],[AC_MSG_RESULT(no)])
	fi

	if test "`uname`" = "HP-UX"; then
	if test "$ac_cv_c_compiler_gnu" = no; then
	# special override for broken HP-UX compiler - I can't find a way to test
	# this properly (its a compiler bug)
	CFLAGS="$CFLAGS -AC99";
	c99_init=yes;
	fi
	fi

	if test x"$c99_init" = x"yes"; then
	saved_CFLAGS=""
	$1
	else
	CFLAGS="$saved_CFLAGS"
	saved_CFLAGS=""
	$2
	fi
	])

	dnl AC_PROG_CC_FLAG(flag)
	AC_DEFUN(AC_PROG_CC_FLAG,
	[AC_CACHE_CHECK(whether ${CC-cc} accepts -$1, ac_cv_prog_cc_$1,
	[echo 'void f(){}' > conftest.c
	if test -z "`${CC-cc} -$1 -c conftest.c 2>&1`"; then
	ac_cv_prog_cc_$1=yes
	else
	ac_cv_prog_cc_$1=no
	fi
	rm -f conftest*
	])])

	dnl see if a declaration exists for a function or variable
	dnl defines HAVE_function_DECL if it exists
	dnl AC_HAVE_DECL(var, includes)
	AC_DEFUN(AC_HAVE_DECL,
	[
	AC_CACHE_CHECK([for $1 declaration],ac_cv_have_$1_decl,[
	AC_TRY_COMPILE([$2],[int i = (int)$1],
	ac_cv_have_$1_decl=yes,ac_cv_have_$1_decl=no)])
	if test x"$ac_cv_have_$1_decl" = x"yes"; then
	AC_DEFINE([HAVE_]translit([$1], [a-z], [A-Z])[_DECL],1,[Whether $1() is available])
	fi
	])


	# AC_CHECK_LIB_EXT(LIBRARY, [EXT_LIBS], [FUNCTION],
	# [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
	# [ADD-ACTION-IF-FOUND],[OTHER-LIBRARIES])
	# ------------------------------------------------------
	#
	# Use a cache variable name containing both the library and function name,
	# because the test really is for library $1 defining function $3, not
	# just for library $1. Separate tests with the same $1 and different $3s
	# may have different results.
	#
	# Note that using directly AS_VAR_PUSHDEF([ac_Lib], [ac_cv_lib_$1_$3])
	# is asking for trouble, since AC_CHECK_LIB($lib, fun) would give
	# ac_cv_lib_$lib_fun, which is definitely not what was meant. Hence
	# the AS_LITERAL_IF indirection.
	#
	# FIXME: This macro is extremely suspicious. It DEFINEs unconditionally,
	# whatever the FUNCTION, in addition to not being a *S macro. Note
	# that the cache does depend upon the function we are looking for.
	#
	# It is on purpose we used `ac_check_lib_ext_save_LIBS' and not just
	# `ac_save_LIBS': there are many macros which don't want to see `LIBS'
	# changed but still want to use AC_CHECK_LIB_EXT, so they save `LIBS'.
	# And ``ac_save_LIBS' is too tempting a name, so let's leave them some
	# freedom.
	AC_DEFUN([AC_CHECK_LIB_EXT],
	[
	AH_CHECK_LIB_EXT([$1])
	ac_check_lib_ext_save_LIBS=$LIBS
	LIBS="-l$1 $$2 $7 $LIBS"
	AS_LITERAL_IF([$1],
	[AS_VAR_PUSHDEF([ac_Lib_ext], [ac_cv_lib_ext_$1])],
	[AS_VAR_PUSHDEF([ac_Lib_ext], [ac_cv_lib_ext_$1''])])dnl

	m4_ifval([$3],
	[
	AH_CHECK_FUNC_EXT([$3])
	AS_LITERAL_IF([$1],
	[AS_VAR_PUSHDEF([ac_Lib_func], [ac_cv_lib_ext_$1_$3])],
	[AS_VAR_PUSHDEF([ac_Lib_func], [ac_cv_lib_ext_$1''_$3])])dnl
	AC_CACHE_CHECK([for $3 in -l$1], ac_Lib_func,
	[AC_TRY_LINK_FUNC($3,
	[AS_VAR_SET(ac_Lib_func, yes);
	AS_VAR_SET(ac_Lib_ext, yes)],
	[AS_VAR_SET(ac_Lib_func, no);
	AS_VAR_SET(ac_Lib_ext, no)])
	])
	AS_IF([test AS_VAR_GET(ac_Lib_func) = yes],
	[AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_$3))])dnl
	AS_VAR_POPDEF([ac_Lib_func])dnl
	],[
	AC_CACHE_CHECK([for -l$1], ac_Lib_ext,
	[AC_TRY_LINK_FUNC([main],
	[AS_VAR_SET(ac_Lib_ext, yes)],
	[AS_VAR_SET(ac_Lib_ext, no)])
	])
	])
	LIBS=$ac_check_lib_ext_save_LIBS

	AS_IF([test AS_VAR_GET(ac_Lib_ext) = yes],
	[m4_default([$4],
	[AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_LIB$1))
	case "$$2" in
	-l$1)
	;;
	*)
	$2="-l$1 $$2"
	;;
	esac])
	[$6]
	],
	[$5])dnl
	AS_VAR_POPDEF([ac_Lib_ext])dnl
	])# AC_CHECK_LIB_EXT

	# AH_CHECK_LIB_EXT(LIBNAME)
	# ---------------------
	m4_define([AH_CHECK_LIB_EXT],
	[AH_TEMPLATE(AS_TR_CPP(HAVE_LIB$1),
	[Define to 1 if you have the `]$1[' library (-l]$1[).])])

	dnl AC_SEARCH_LIBS_EXT(FUNCTION, SEARCH-LIBS, EXT_LIBS,
	dnl [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
	dnl [OTHER-LIBRARIES])
	dnl --------------------------------------------------------
	dnl Search for a library defining FUNC, if it's not already available.
	AC_DEFUN([AC_SEARCH_LIBS_EXT],
	[AC_CACHE_CHECK([for library containing $1], [ac_cv_search_ext_$1],
	[
	ac_func_search_ext_save_LIBS=$LIBS
	ac_cv_search_ext_$1=no
	AC_LINK_IFELSE([AC_LANG_CALL([], [$1])],
	[ac_cv_search_ext_$1="none required"])
	if test "$ac_cv_search_ext_$1" = no; then
	for ac_lib in $2; do
	LIBS="-l$ac_lib $$3 $6 $ac_func_search_save_ext_LIBS"
	AC_LINK_IFELSE([AC_LANG_CALL([], [$1])],
	[ac_cv_search_ext_$1="-l$ac_lib"
	break])
	done
	fi
	LIBS=$ac_func_search_ext_save_LIBS])
	AS_IF([test "$ac_cv_search_ext_$1" != no],
	[test "$ac_cv_search_ext_$1" = "none required" \|\| $3="$ac_cv_search_ext_$1 $$3"
	$4],
	[$5])dnl
	])

	dnl check for a function in a $LIBS and $OTHER_LIBS libraries variable.
	dnl AC_CHECK_FUNC_EXT(func,OTHER_LIBS,IF-TRUE,IF-FALSE)
	AC_DEFUN([AC_CHECK_FUNC_EXT],
	[
	AH_CHECK_FUNC_EXT($1)
	ac_check_func_ext_save_LIBS=$LIBS
	LIBS="$2 $LIBS"
	AS_VAR_PUSHDEF([ac_var], [ac_cv_func_ext_$1])dnl
	AC_CACHE_CHECK([for $1], ac_var,
	[AC_LINK_IFELSE([AC_LANG_FUNC_LINK_TRY([$1])],
	[AS_VAR_SET(ac_var, yes)],
	[AS_VAR_SET(ac_var, no)])])
	LIBS=$ac_check_func_ext_save_LIBS
	AS_IF([test AS_VAR_GET(ac_var) = yes],
	[AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_$1])) $3],
	[$4])dnl
	AS_VAR_POPDEF([ac_var])dnl
	])# AC_CHECK_FUNC

	# AH_CHECK_FUNC_EXT(FUNCNAME)
	# ---------------------
	m4_define([AH_CHECK_FUNC_EXT],
	[AH_TEMPLATE(AS_TR_CPP(HAVE_$1),
	[Define to 1 if you have the `]$1[' function.])])

	dnl Define an AC_DEFINE with ifndef guard.
	dnl AC_N_DEFINE(VARIABLE [, VALUE])
	AC_DEFUN([AC_N_DEFINE],
	[
	AH_VERBATIM([$1], [
	#ifndef $1
	# undef $1
	#endif
	])

	cat >>confdefs.h <<\EOF
	#ifndef $1
	[#define] $1 m4_if($#, 1, 1, [$2])
	#endif
	EOF
	])

	dnl Add an #include
	dnl AC_ADD_INCLUDE(VARIABLE)
	define(AC_ADD_INCLUDE,
	[cat >> confdefs.h <<\EOF
	[#include] $1
	EOF
	])

	dnl remove an #include
	dnl AC_REMOVE_INCLUDE(VARIABLE)
	define(AC_REMOVE_INCLUDE,
	[
	grep -v '[#include] $1' confdefs.h >confdefs.h.tmp
	cat confdefs.h.tmp > confdefs.h
	rm confdefs.h.tmp
	])

	dnl remove an #define
	dnl AC_REMOVE_DEFINE(VARIABLE)
	define(AC_REMOVE_DEFINE,
	[
	grep -v '[#define] $1 ' confdefs.h \|grep -v '[#define] $1[$]'>confdefs.h.tmp
	cat confdefs.h.tmp > confdefs.h
	rm confdefs.h.tmp
	])

	dnl AS_HELP_STRING is not available in autoconf 2.57, and AC_HELP_STRING is deprecated
	dnl in autoconf 2.59, so define AS_HELP_STRING to be AC_HELP_STRING unless it is already
	dnl defined.
	m4_ifdef([AS_HELP_STRING], , [m4_define([AS_HELP_STRING], m4_defn([AC_HELP_STRING]))])

	dnl check if the prototype in the header matches the given one
	dnl AC_VERIFY_C_PROTOTYPE(prototype,functionbody,[IF-TRUE].[IF-FALSE],[extraheaders])
	AC_DEFUN(AC_VERIFY_C_PROTOTYPE,
	[AC_CACHE_CHECK([for prototype $1], AS_TR_SH([ac_cv_c_prototype_$1]),
	AC_COMPILE_IFELSE([AC_LANG_SOURCE([
	AC_INCLUDES_DEFAULT
	$5
	$1
	{
	$2
	}
	])],[
	AS_TR_SH([ac_cv_c_prototype_$1])=yes
	],[
	AS_TR_SH([ac_cv_c_prototype_$1])=no
	])
	)
	AS_IF([test $AS_TR_SH([ac_cv_c_prototype_$1]) = yes],[$3],[$4])
	])

	AC_DEFUN(LIBREPLACE_PROVIDE_HEADER,
	[AC_CHECK_HEADER([$1],
	[ AC_CONFIG_COMMANDS(rm-$1, [rm -f $libreplacedir/$1], [libreplacedir=$libreplacedir]) ],
	[ AC_CONFIG_COMMANDS(mk-$1, [echo "#include \"replace.h\"" > $libreplacedir/$1], [libreplacedir=$libreplacedir]) ]
	)
	])

	dnl AC_HAVE_TYPE(TYPE,INCLUDES)
	AC_DEFUN([AC_HAVE_TYPE], [
	AC_REQUIRE([AC_HEADER_STDC])
	cv=`echo "$1" \| sed 'y%./+- %__p__%'`
	AC_MSG_CHECKING(for $1)
	AC_CACHE_VAL([ac_cv_type_$cv],
	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
	AC_INCLUDES_DEFAULT
	$2]],
	[[$1 foo;]])],
	[eval "ac_cv_type_$cv=yes"],
	[eval "ac_cv_type_$cv=no"]))dnl
	ac_foo=`eval echo \\$ac_cv_type_$cv`
	AC_MSG_RESULT($ac_foo)
	if test "$ac_foo" = yes; then
	ac_tr_hdr=HAVE_`echo $1 \| sed 'y%abcdefghijklmnopqrstuvwxyz./- %ABCDEFGHIJKLMNOPQRSTUVWXYZ____%'`
	if false; then
	AC_CHECK_TYPES($1)
	fi
	AC_DEFINE_UNQUOTED($ac_tr_hdr, 1, [Define if you have type `$1'])
	fi
	])