| | 1 | /* |
| | 2 | * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. |
| | 3 | * |
| | 4 | * @APPLE_LICENSE_HEADER_START@ |
| | 5 | * |
| | 6 | * The contents of this file constitute Original Code as defined in and |
| | 7 | * are subject to the Apple Public Source License Version 1.1 (the |
| | 8 | * "License"). You may not use this file except in compliance with the |
| | 9 | * License. Please obtain a copy of the License at |
| | 10 | * http://www.apple.com/publicsource and read it before using this file. |
| | 11 | * |
| | 12 | * This Original Code and all software distributed under the License are |
| | 13 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| | 14 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| | 15 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
| | 16 | * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the |
| | 17 | * License for the specific language governing rights and limitations |
| | 18 | * under the License. |
| | 19 | * |
| | 20 | * @APPLE_LICENSE_HEADER_END@ |
| | 21 | */ |
| | 22 | /* |
| | 23 | * @OSF_COPYRIGHT@ |
| | 24 | * |
| | 25 | */ |
| | 26 | |
| | 27 | #ifndef _MACHINE_ENDIAN_H_ |
| | 28 | #define _MACHINE_ENDIAN_H_ |
| | 29 | |
| | 30 | /* |
| | 31 | * Definitions for byte order, |
| | 32 | * according to byte significance from low address to high. |
| | 33 | */ |
| | 34 | #define LITTLE_ENDIAN 1234 /* least-significant byte first (vax) */ |
| | 35 | #define BIG_ENDIAN 4321 /* most-significant byte first (IBM, net) */ |
| | 36 | #define PDP_ENDIAN 3412 /* LSB first in word, MSW first in long (pdp) */ |
| | 37 | |
| | 38 | #if _BIG_ENDIAN /* Predefined by compiler */ |
| | 39 | #define BYTE_ORDER BIG_ENDIAN /* byte order we use on ppc */ |
| | 40 | #define ENDIAN BIG |
| | 41 | #else |
| | 42 | #error code has not been ported to little endian targets yet |
| | 43 | #endif |
| | 44 | |
| | 45 | /* |
| | 46 | * Macros for network/external number representation conversion. |
| | 47 | */ |
| | 48 | #if BYTE_ORDER == BIG_ENDIAN && !defined(lint) |
| | 49 | #define ntohl(x) (x) |
| | 50 | #define ntohs(x) (x) |
| | 51 | #define htonl(x) (x) |
| | 52 | #define htons(x) (x) |
| | 53 | |
| | 54 | static __inline__ unsigned int byte_reverse_word(unsigned int word); |
| | 55 | static __inline__ unsigned int byte_reverse_word(unsigned int word) { |
| | 56 | unsigned int result; |
| | 57 | __asm__ volatile("lwbrx %0, 0, %1" : "=r" (result) : "r" (&word)); |
| | 58 | return result; |
| | 59 | } |
| | 60 | |
| | 61 | /* The above function is commutative, so we can use it for |
| | 62 | * translations in both directions (to/from little endianness) |
| | 63 | * Note that htolx and ltohx are probably identical, they are |
| | 64 | * included for completeness. |
| | 65 | */ |
| | 66 | #define htoll(x) byte_reverse_word(x) |
| | 67 | #define htols(x) (byte_reverse_word(x) >> 16) |
| | 68 | #define ltohl(x) htoll(x) |
| | 69 | #define ltohs(x) htols(x) |
| | 70 | |
| | 71 | #define htobl(x) (x) |
| | 72 | #define htobs(x) (x) |
| | 73 | #define btohl(x) (x) |
| | 74 | #define btohs(x) (x) |
| | 75 | |
| | 76 | #else |
| | 77 | unsigned short ntohs(), htons(); |
| | 78 | unsigned long ntohl(), htonl(); |
| | 79 | #endif |
| | 80 | |
| | 81 | /* This defines the order of elements in a bitfield, |
| | 82 | * it is principally used by the SCSI subsystem in |
| | 83 | * the definitions of mapped registers |
| | 84 | */ |
| | 85 | #define BYTE_MSF 1 |
| | 86 | |
| | 87 | #endif /* _MACHINE_ENDIAN_H_ */ |
projects / apple / xnu.git / blame_incremental