diff options
Diffstat (limited to 'm4/ax_decl_wchar_max.m4')
| -rw-r--r-- | m4/ax_decl_wchar_max.m4 | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/m4/ax_decl_wchar_max.m4 b/m4/ax_decl_wchar_max.m4 new file mode 100644 index 0000000000000..e01604da5878a --- /dev/null +++ b/m4/ax_decl_wchar_max.m4 @@ -0,0 +1,38 @@ +dnl @synopsis AX_DECL_WCHAR_MAX +dnl +dnl Checks whether the system headers define WCHAR_MAX or not. If it is +dnl already defined, does nothing. Otherwise checks the size and signedness +dnl of `wchar_t', and defines WCHAR_MAX to the maximum value that can be +dnl stored in a variable of type `wchar_t'. +dnl +dnl @version 1.1 +dnl @author Ville Laurikari <vl@iki.fi> +dnl +AC_DEFUN([AX_DECL_WCHAR_MAX], [ + AC_CACHE_CHECK([whether WCHAR_MAX is defined], ax_cv_decl_wchar_max, [ + AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([ +#ifdef HAVE_WCHAR_H +#include <wchar.h> +#endif +], [WCHAR_MAX])], + [ax_cv_decl_wchar_max="yes"], + [ax_cv_decl_wchar_max="no"])]) + if test $ax_cv_decl_wchar_max = "no"; then + AX_CHECK_SIGN([wchar_t], + [ wc_signed="yes" + AC_DEFINE(WCHAR_T_SIGNED, 1, [Define if wchar_t is signed]) ], + [ wc_signed="no" + AC_DEFINE(WCHAR_T_UNSIGNED, 1, [Define if wchar_t is unsigned])], [ +#ifdef HAVE_WCHAR_H +#include <wchar.h> +#endif +]) + if test "$wc_signed" = "yes"; then + AC_DEFINE(WCHAR_MAX, [(1L << (sizeof(wchar_t) * 8 - 1) - 1)], [ +Define to the maximum value of wchar_t if not already defined elsewhere]) + elif test "$wc_signed" = "no"; then + AC_DEFINE(WCHAR_MAX, [(1L << (sizeof(wchar_t) * 8) - 1)]) + fi + fi +])dnl |