From eebab307ea36888ccac39a970c56ffbf87d05163 Mon Sep 17 00:00:00 2001
From: Marko Kreen <markokr@gmail.com>
Date: Wed, 26 Jan 2011 14:31:47 +0200
Subject: [PATCH] endian: autoconf detection for enc/dec functions

---
 m4/usual.m4    | 21 +++++++++++++++++++++
 usual/endian.h |  4 ++++
 2 files changed, 25 insertions(+)

diff --git a/m4/usual.m4 b/m4/usual.m4
index 7fb894c..5f1f4fc 100644
--- a/m4/usual.m4
+++ b/m4/usual.m4
@@ -152,6 +152,27 @@ AC_CHECK_FUNCS(syslog mmap recvmsg sendmsg getpeerucred)
 ### win32: link with ws2_32
 AC_SEARCH_LIBS(WSAGetLastError, ws2_32)
 AC_FUNC_STRERROR_R
+###
+AC_MSG_CHECKING([for integer enc/dec functions])
+AC_LINK_IFELSE([
+  #include <sys/types.h>
+  #ifdef HAVE_SYS_ENDIAN_H
+  #include <sys/endian.h>
+  #endif
+  #ifdef HAVE_ENDIAN_H
+  #include <endian.h>
+  #endif
+  char p[[]] = "01234567";
+  int main(void) {
+    be16enc(p, 0); be32enc(p, 1); be64enc(p, 2);
+    le16enc(p, 2); le32enc(p, 3); le64enc(p, 4);
+    return (int)(be16dec(p) + be32dec(p) + be64dec(p)) +
+           (int)(le16dec(p) + le32dec(p) + le64dec(p));
+  } ],
+[ AC_MSG_RESULT([found])
+  AC_DEFINE([HAVE_ENCDEC_FUNCS], [1], [Define if *enc & *dec functions are available]) ],
+[AC_MSG_RESULT([not found])])
+
 ])
 
 dnl
diff --git a/usual/endian.h b/usual/endian.h
index 2c4d70b..1da1c09 100644
--- a/usual/endian.h
+++ b/usual/endian.h
@@ -158,6 +158,8 @@ static inline uint64_t _gen_bswap64(uint64_t x)
  * Read LE/BE values from memory.
  */
 
+#ifndef HAVE_ENCDEC_FUNCS
+
 #define _DEC(name, typ, decode) \
 static inline typ name(const void *p) { \
 	typ tmp; \
@@ -190,4 +192,6 @@ _ENC(le32enc, uint32_t, htole32)
 _ENC(le64enc, uint64_t, htole64)
 #undef _ENC
 
+#endif /* !HAVE_ENCDEC_FUNCS */
+
 #endif	/* _USUAL_ENDIAN_H_ */
-- 
2.39.5