xref: /illumos-gate/usr/src/uts/intel/asm/byteorder.h (revision 581cede61ac9c14d8d4ea452562a567189eead78)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef _ASM_BYTEORDER_H
27 #define	_ASM_BYTEORDER_H
28 
29 #include <sys/types.h>
30 
31 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 #if !defined(__lint) && defined(__GNUC__)
36 
37 /*
38  * htonll(), ntohll(), htonl(), ntohl(), htons(), ntohs()
39  * These functions reverse the byte order of the input parameter and returns
40  * the result.  This is to convert the byte order from host byte order
41  * (little endian) to network byte order (big endian), or vice versa.
42  */
43 
44 
45 #if defined(__i386) || defined(__amd64)
46 
47 extern __inline__ uint16_t htons(uint16_t value)
48 {
49 #if defined(__amd64)
50 	__asm__("xchgb %h0, %b0" : "+Q" (value));
51 #elif defined(__i386)
52 	__asm__("xchgb %h0, %b0" : "+q" (value));
53 #endif
54 	return (value);
55 }
56 
57 extern __inline__ uint16_t ntohs(uint16_t value)
58 {
59 #if defined(__amd64)
60 	__asm__("xchgb %h0, %b0" : "+Q" (value));
61 #elif defined(__i386)
62 	__asm__("xchgb %h0, %b0" : "+q" (value));
63 #endif
64 	return (value);
65 }
66 
67 extern __inline__ uint32_t htonl(uint32_t value)
68 {
69 	__asm__("bswap %0" : "+r" (value));
70 	return (value);
71 }
72 
73 extern __inline__ uint32_t ntohl(uint32_t value)
74 {
75 	__asm__("bswap %0" : "+r" (value));
76 	return (value);
77 }
78 
79 #if defined(__amd64)
80 extern __inline__ uint64_t htonll(uint64_t value)
81 {
82 	__asm__("bswapq %0" : "+r" (value));
83 	return (value);
84 }
85 
86 extern __inline__ uint64_t ntohll(uint64_t value)
87 {
88 	__asm__("bswapq %0" : "+r" (value));
89 	return (value);
90 }
91 
92 #elif defined(__i386)
93 /* Use the htonl() and ntohl() inline functions defined above */
94 extern __inline__ uint64_t htonll(uint64_t value)
95 {
96 	return (htonl(value >> 32) | ((uint64_t)htonl(value) << 32));
97 }
98 
99 extern __inline__ uint64_t ntohll(uint64_t value)
100 {
101 	return (ntohl(value >> 32) | (uint64_t)ntohl(value) << 32);
102 }
103 #endif	/* __amd64 */
104 
105 #endif	/* __i386 || __amd64 */
106 
107 #endif	/* !__lint && __GNUC__ */
108 
109 #ifdef	__cplusplus
110 }
111 #endif
112 
113 #endif	/* _ASM_BYTEORDER_H */
114