From 72fcf757553965ab7f9fca108768b7c4b843baff Mon Sep 17 00:00:00 2001
From: David Polverari <david.polverari@gmail.com>
Date: Sat, 15 Oct 2022 16:23:06 -0300
Subject: [PATCH] Add support for runtime endianness check

dcfldd SHA1 implementation can perform endianness runtime checks if
RUNTIME_ENDIAN is defined.

This commit adds suport for enabling runtime endianness check by using
the '--enable-runtime-endian-check' option during configure. The option
is disabled by default.
---
 configure.ac | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/configure.ac b/configure.ac
index 9fc7f70..34821b8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -41,6 +41,15 @@ AC_C_BIGENDIAN
 AC_TYPE_OFF_T
 AC_TYPE_SIZE_T
 
+AC_ARG_ENABLE([runtime-endian-check],
+    AC_HELP_STRING([--enable-runtime-endian-check], [Enable runtime tests for big- or little-endian byte order (default is NO)])
+)
+
+AS_IF([test "x$enable_runtime_endian_check" = "xyes"], [
+    dnl Do the stuff needed for enabling the feature
+    AC_DEFINE([RUNTIME_ENDIAN], 1, [Should a function (run-time) be used to determine the byte order?])
+])
+
 AC_CHECK_DECLS([strtol, strtoul, strtoumax, strndup])
 
 AC_CONFIG_FILES([Makefile src/Makefile])