From: Michael Brown <mcb30@ipxe.org>
Date: Thu, 15 Jul 2021 12:46:34 +0000 (+0100)
Subject: [libc] Allow for externally-defined LITTLE_ENDIAN and BIG_ENDIAN constants
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8d08300ad945988e0ce2fc24a34c19613154bae5;p=thirdparty%2Fipxe.git

[libc] Allow for externally-defined LITTLE_ENDIAN and BIG_ENDIAN constants

When building the Linux userspace binaries, the external system
headers may have already defined values for the __LITTLE_ENDIAN and
__BIG_ENDIAN constants.

Fix by retaining the existing values if already defined, since the
actual values of these constants do not matter.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/include/endian.h b/src/include/endian.h
index 79c3163ee..bdae9de45 100644
--- a/src/include/endian.h
+++ b/src/include/endian.h
@@ -8,14 +8,18 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  * Little-endian systems should define BYTE_ORDER as LITTLE_ENDIAN.
  * This constant is intended to be used only at compile time.
  */
+#ifndef __LITTLE_ENDIAN
 #define __LITTLE_ENDIAN 0x44332211UL
+#endif
 
 /** Constant representing big-endian byte order
  *
  * Big-endian systems should define BYTE_ORDER as BIG_ENDIAN.
  * This constant is intended to be used only at compile time.
  */
+#ifndef __BIG_ENDIAN
 #define __BIG_ENDIAN 0x11223344UL
+#endif
 
 #include "bits/endian.h"