BSD compatibility for <machine/endian.h>

Introduce <machine/_endian.h> to let target based customization of
<machine/endian.h> via

 * _LITTLE_ENDIAN,
 * _BIG_ENDIAN,
 * _PDP_ENDIAN, and
 * _BYTE_ORDER.

defines.  Add definitions expected by FreeBSD to
<machine/endian.h> like

 * _QUAD_HIGHWORD,
 * _QUAD_LOWWORD,
 * __bswap16(),
 * __bswap32(),
 * __bswap64(),
 * __htonl(),
 * __htons(),
 * __ntohl(), and
 * __ntohs().

Also, if __BSD_VISIBLE

 * LITTLE_ENDIAN,
 * BIG_ENDIAN,
 * PDP_ENDIAN, and
 * BYTE_ORDER.

Targets that define __machine_host_to_from_network_defined in
<machine/_endian.h> must provide their own implementation of

 * __htonl(),
 * __htons(),
 * __ntohl(), and
 * __ntohs(),

otherwise a default implementation is provided by <machine/endian.h>.
In case of GCC defines to builtins are used.

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>

3 files changed, 59 insertions, 29 deletions

diff --git a/winsup/cygwin/include/asm/byteorder.h b/winsup/cygwin/include/asm/byteorder.h
index 4f5d7cb59..14529bfa2 100644
--- a/winsup/cygwin/include/asm/byteorder.h
+++ b/winsup/cygwin/include/asm/byteorder.h
@@ -11,9 +11,8 @@ details. */
 #ifndef _I386_BYTEORDER_H
 #define _I386_BYTEORDER_H
 
-#include <_ansi.h>
 #include <stdint.h>
-#include <bits/endian.h>
+#include <machine/endian.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -28,37 +27,16 @@ extern uint16_t	ntohs(uint16_t);
 extern uint32_t	htonl(uint32_t);
 extern uint16_t	htons(uint16_t);
 
-_ELIDABLE_INLINE uint32_t __ntohl(uint32_t);
-_ELIDABLE_INLINE uint16_t __ntohs(uint16_t);
-
-_ELIDABLE_INLINE uint32_t
-__ntohl(uint32_t x)
-{
-	__asm__("bswap %0" : "=r" (x) : "0" (x));
-	return x;
-}
-
 #define __constant_ntohl(x) \
 	((uint32_t)((((uint32_t)(x) & 0x000000ffU) << 24) | \
 		   (((uint32_t)(x) & 0x0000ff00U) <<  8) | \
 		   (((uint32_t)(x) & 0x00ff0000U) >>  8) | \
 		   (((uint32_t)(x) & 0xff000000U) >> 24)))
 
-_ELIDABLE_INLINE uint16_t
-__ntohs(uint16_t x)
-{
-	__asm__("xchgb %b0,%h0"		/* swap bytes		*/
-		: "=Q" (x)
-		:  "0" (x));
-	return x;
-}
-
 #define __constant_ntohs(x) \
 	((uint16_t)((((uint16_t)(x) & 0x00ff) << 8) | \
 		   (((uint16_t)(x) & 0xff00) >> 8))) \
 
-#define __htonl(x) __ntohl(x)
-#define __htons(x) __ntohs(x)
 #define __constant_htonl(x) __constant_ntohl(x)
 #define __constant_htons(x) __constant_ntohs(x)
 
diff --git a/winsup/cygwin/include/endian.h b/winsup/cygwin/include/endian.h
index 960e61c3d..7ddf0994d 100644
--- a/winsup/cygwin/include/endian.h
+++ b/winsup/cygwin/include/endian.h
@@ -12,14 +12,21 @@ details. */
 #define _ENDIAN_H_
 
 #include <sys/config.h>
-#include <sys/cdefs.h>
-#include <bits/endian.h>
+#include <machine/endian.h>
 
 /*#ifdef  __USE_BSD*/
-# define LITTLE_ENDIAN  __LITTLE_ENDIAN
-# define BIG_ENDIAN     __BIG_ENDIAN
-# define PDP_ENDIAN     __PDP_ENDIAN
-# define BYTE_ORDER     __BYTE_ORDER
+# ifndef LITTLE_ENDIAN
+#  define LITTLE_ENDIAN __LITTLE_ENDIAN
+# endif
+# ifndef BIG_ENDIAN
+#  define BIG_ENDIAN    __BIG_ENDIAN
+# endif
+# ifndef PDP_ENDIAN
+#  define PDP_ENDIAN    __PDP_ENDIAN
+# endif
+# ifndef BYTE_ORDER
+#  define BYTE_ORDER    __BYTE_ORDER
+# endif
 /*#endif*/
 
 #if __BYTE_ORDER == __LITTLE_ENDIAN
diff --git a/winsup/cygwin/include/machine/_endian.h b/winsup/cygwin/include/machine/_endian.h
new file mode 100644
index 000000000..d878cc180
--- /dev/null
+++ b/winsup/cygwin/include/machine/_endian.h
@@ -0,0 +1,45 @@
+/* machine/_endian.h
+
+   Copyright 2005, 2010, 2011 Red Hat, Inc.
+
+This file is part of Cygwin.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#ifndef __MACHINE_ENDIAN_H__
+#error "must be included via <machine/endian.h>"
+#endif /* !__MACHINE_ENDIAN_H__ */
+
+#include <_ansi.h>
+#include <bits/endian.h>
+
+#define _LITTLE_ENDIAN __LITTLE_ENDIAN
+#define _BIG_ENDIAN    __BIG_ENDIAN
+#define _PDP_ENDIAN    __PDP_ENDIAN
+#define _BYTE_ORDER    __BYTE_ORDER
+
+#define __machine_host_to_from_network_defined
+
+_ELIDABLE_INLINE __uint32_t __ntohl(__uint32_t);
+_ELIDABLE_INLINE __uint16_t __ntohs(__uint16_t);
+
+_ELIDABLE_INLINE __uint32_t
+__ntohl(__uint32_t _x)
+{
+	__asm__("bswap %0" : "=r" (_x) : "0" (_x));
+	return _x;
+}
+
+_ELIDABLE_INLINE __uint16_t
+__ntohs(__uint16_t _x)
+{
+	__asm__("xchgb %b0,%h0"		/* swap bytes		*/
+		: "=Q" (_x)
+		:  "0" (_x));
+	return _x;
+}
+
+#define __htonl(_x) __ntohl(_x)
+#define __htons(_x) __ntohs(_x)