1 files changed, 34 insertions, 0 deletions
diff --git a/m4/xstrtoumax.m4 b/m4/xstrtoumax.m4
new file mode 100644
index 00000000..f6e31996
--- /dev/null
+++ b/m4/xstrtoumax.m4
@@ -0,0 +1,34 @@
+#serial 2
+
+# autoconf tests required for use of xstrtoumax.c
+
+AC_DEFUN(jm_AC_PREREQ_XSTRTOUMAX,
+[
+  AC_REQUIRE([jm_AC_HEADER_INTTYPES_H])
+  AC_REQUIRE([jm_AC_TYPE_UNSIGNED_LONG_LONG])
+  AC_CHECK_HEADERS(stdlib.h)
+
+  AC_CACHE_CHECK([whether <inttypes.h> defines strtoumax as a macro],
+    jm_cv_func_strtoumax_macro,
+    AC_EGREP_CPP([inttypes_h_defines_strtoumax], [#include <inttypes.h>
+#ifdef strtoumax
+ inttypes_h_defines_strtoumax
+#endif],
+      jm_cv_func_strtoumax_macro=yes,
+      jm_cv_func_strtoumax_macro=no))
+
+  if test "$jm_cv_func_strtoumax_macro" != yes; then
+    AC_REPLACE_FUNCS(strtoumax)
+  fi
+
+  dnl We don't need (and can't compile) the replacement strtoull
+  dnl unless the type `unsigned long long' exists.
+  dnl Also, only the replacement strtoumax invokes strtoull,
+  dnl so we need the replacement strtoull only if strtoumax does not exist.
+  case "$ac_cv_type_unsigned_long_long,$jm_cv_func_strtoumax_macro,$ac_cv_func_strtoumax" in
+    yes,no,no)
+      AC_REPLACE_FUNCS(strtoull)
+      ;;
+  esac
+
+])