funcdecl.m4

mutt-1.5.12 源代码。linux 下邮件接受的工具。

dnl ---------------------------------------------------------------------------
dnl Check if a function is declared by including a set of include files.
dnl Invoke the corresponding actions according to whether it is found or not.
dnl
dnl Gcc (unlike other compilers) will only warn about the miscast assignment
dnl in the first test, but most compilers will oblige with an error in the
dnl second test.
dnl
dnl CF_CHECK_FUNCDECL(INCLUDES, FUNCTION, [ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]])
AC_DEFUN([CF_CHECK_FUNCDECL],
[
AC_MSG_CHECKING([for $2 declaration])
AC_CACHE_VAL(ac_cv_func_decl_$2,
[AC_TRY_COMPILE([$1],
[#ifndef ${ac_func}
extern	int	${ac_func}();
#endif],[
AC_TRY_COMPILE([$1],
[#ifndef ${ac_func}
int	(*p)() = ${ac_func};
#endif],[
eval "ac_cv_func_decl_$2=yes"],[
eval "ac_cv_func_decl_$2=no"])],[
eval "ac_cv_func_decl_$2=yes"])])
if eval "test \"`echo '$ac_cv_func_'decl_$2`\" = yes"; then
  AC_MSG_RESULT(yes)
  ifelse([$3], , :, [$3])
else
  AC_MSG_RESULT(no)
ifelse([$4], , , [$4
])dnl
fi
])dnl
dnl ---------------------------------------------------------------------------
dnl Check if functions are declared by including a set of include files.
dnl and define DECL_XXX if not.
dnl
dnl CF_CHECK_FUNCDECLS(INCLUDES, FUNCTION... [, ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]])
AC_DEFUN([CF_CHECK_FUNCDECLS],
[for ac_func in $2
do
CF_CHECK_FUNCDECL([$1], $ac_func,
[
  CF_UPPER(ac_tr_func,HAVE_$ac_func)
  AC_DEFINE_UNQUOTED($ac_tr_func) $3],
[$4])dnl
dnl [$3],
dnl [
dnl   CF_UPPER(ac_tr_func,DECL_$ac_func)
dnl   AC_DEFINE_UNQUOTED($ac_tr_func) $4])dnl
done
])dnl
dnl ---------------------------------------------------------------------------
dnl Make an uppercase version of a variable
dnl $1=uppercase($2)
AC_DEFUN([CF_UPPER],
[
changequote(,)dnl
$1=`echo $2 | tr '[a-z]' '[A-Z]'`
changequote([,])dnl
])dnl
dnl ---------------------------------------------------------------------------