xnu-3247.1.106.tar.gz

[apple/xnu.git] / osfmk / i386 / endian.h

diff --git a/osfmk/i386/endian.h b/osfmk/i386/endian.h
index 0f802c36ad3a88c7edd017aad888a1bf3894f984..24851958871eafbb0d7eefd9f61ce57c2cc1c1d9 100644 (file)
--- a/osfmk/i386/endian.h
+++ b/osfmk/i386/endian.h
@@ -1,16 +1,19 @@
 /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
@@ -20,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
@@ -43,36 +46,44 @@
 
 /*
  * Macros for network/external number representation conversion.
- */
-
-unsigned short ntohs(unsigned short), htons(unsigned short);
-unsigned long  ntohl(unsigned long), htonl(unsigned long);
-
-/*
  * Use GNUC support to inline the byteswappers.
  */
 
-extern __inline__
+#if !defined(ntohs)
+static __inline__ unsigned short       ntohs(unsigned short);
+static __inline__
 unsigned short
 ntohs(unsigned short w_int)
 {
-       register unsigned short w = w_int;
-       __asm__ volatile("xchgb %h1,%b1" : "=q" (w) : "0" (w));
-       return (w);     /* zero-extend for compat */
+       return ((w_int << 8) | (w_int >> 8));
 }
+#endif
 
+#if !defined(htons)
+unsigned short htons(unsigned short);
 #define        htons   ntohs
+#endif
 
-extern __inline__
+#if !defined(ntohl)
+static __inline__ unsigned long        ntohl(unsigned long);
+static __inline__
 unsigned long
 ntohl(register unsigned long value)
 {
+#if defined(__clang__)
+       return (unsigned long)__builtin_bswap32((unsigned int)value);
+#else
        register unsigned long l = value;
        __asm__ volatile("bswap %0" : "=r" (l) : "0" (l));
        return l;
+#endif
 }
+#endif
 
+#if !defined(htonl)
+unsigned long  htonl(unsigned long);
 #define htonl  ntohl
+#endif
 
 #define NTOHL(x)       (x) = ntohl((unsigned long)x)
 #define NTOHS(x)       (x) = ntohs((unsigned short)x)