libkern/libkern/machine/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1999 Apple Computer, Inc.  All rights reserved.
  27  *
  28  * HISTORY
  29  *
  30  */
  31
  32
  33 #ifndef _OS_OSBYTEORDERMACHINE_H
  34 #define _OS_OSBYTEORDERMACHINE_H
  35
  36 #include <libkern/OSTypes.h>
  37
  38 /* Functions for byte reversed loads. */
  39
  40 OS_INLINE
  41 UInt16
  42 OSReadSwapInt16(
  43     volatile void               * base,
  44     UInt                          offset
  45 )
  46 {
  47     union sconv {
  48         UInt16 us;
  49         UInt8  uc[2];
  50     } *inp, outv;
  51     inp = (union sconv *)((UInt8 *)base + offset);
  52     outv.uc[0] = inp->uc[1];
  53     outv.uc[1] = inp->uc[0];
  54     return (outv.us);
  55 }
  56
  57 OS_INLINE
  58 UInt32
  59 OSReadSwapInt32(
  60     volatile void               * base,
  61     UInt                          offset
  62 )
  63 {
  64     union lconv {
  65         UInt32 ul;
  66         UInt8  uc[4];
  67     } *inp, outv;
  68     inp = (union lconv *)((UInt8 *)base + offset);
  69     outv.uc[0] = inp->uc[3];
  70     outv.uc[1] = inp->uc[2];
  71     outv.uc[2] = inp->uc[1];
  72     outv.uc[3] = inp->uc[0];
  73     return (outv.ul);
  74 }
  75
  76 OS_INLINE
  77 UInt64
  78 OSReadSwapInt64(
  79     volatile void               * base,
  80     UInt                          offset
  81 )
  82 {
  83     union llconv {
  84         UInt64 ull;
  85         UInt8  uc[8];
  86     } *inp, outv;
  87     inp = (union llconv *)((UInt8 *)base + offset);
  88     outv.uc[0] = inp->uc[7];
  89     outv.uc[1] = inp->uc[6];
  90     outv.uc[2] = inp->uc[5];
  91     outv.uc[3] = inp->uc[4];
  92     outv.uc[4] = inp->uc[3];
  93     outv.uc[5] = inp->uc[2];
  94     outv.uc[6] = inp->uc[1];
  95     outv.uc[7] = inp->uc[0];
  96     return (outv.ull);
  97 }
  98
  99 OS_INLINE
 100 UInt
 101 OSReadSwapInt(
 102     volatile void               * base,
 103     UInt                          offset
 104 )
 105 {
 106     return (UInt)OSReadSwapInt32(base, offset);
 107 }
 108
 109 /* Functions for byte reversed stores. */
 110
 111 OS_INLINE
 112 void
 113 OSWriteSwapInt16(
 114     volatile void               * base,
 115     UInt                          offset,
 116     UInt16                        data
 117 )
 118 {
 119     union sconv {
 120         UInt16 us;
 121         UInt8  uc[2];
 122     } *inp, *outp;
 123     inp  = (union sconv *)((UInt8 *)base + offset);
 124     outp = (union sconv *)&data;
 125     outp->uc[0] = inp->uc[1];
 126     outp->uc[1] = inp->uc[0];
 127 }
 128
 129 OS_INLINE
 130 void
 131 OSWriteSwapInt32(
 132     volatile void               * base,
 133     UInt                          offset,
 134     UInt32                        data
 135 )
 136 {
 137     union lconv {
 138         UInt32 ul;
 139         UInt8  uc[4];
 140     } *inp, *outp;
 141     inp  = (union lconv *)((UInt8 *)base + offset);
 142     outp = (union lconv *)&data;
 143     outp->uc[0] = inp->uc[3];
 144     outp->uc[1] = inp->uc[2];
 145     outp->uc[2] = inp->uc[1];
 146     outp->uc[3] = inp->uc[0];
 147 }
 148
 149 OS_INLINE
 150 void
 151 OSWriteSwapInt64(
 152     volatile void               * base,
 153     UInt                          offset,
 154     UInt64                        data
 155 )
 156 {
 157     union llconv {
 158         UInt64 ull;
 159         UInt8  uc[8];
 160     } *inp, *outp;
 161     inp = (union llconv *)((UInt8 *)base + offset);
 162     outp = (union llconv *)&data;
 163     outp->uc[0] = inp->uc[7];
 164     outp->uc[1] = inp->uc[6];
 165     outp->uc[2] = inp->uc[5];
 166     outp->uc[3] = inp->uc[4];
 167     outp->uc[4] = inp->uc[3];
 168     outp->uc[5] = inp->uc[2];
 169     outp->uc[6] = inp->uc[1];
 170     outp->uc[7] = inp->uc[0];
 171 }
 172
 173 OS_INLINE
 174 void
 175 OSWriteSwapInt(
 176     volatile void               * base,
 177     UInt                          offset,
 178     UInt                          data
 179 )
 180 {
 181     OSWriteSwapInt32(base, offset, (UInt32)data);
 182 }
 183
 184 /* Generic byte swapping functions. */
 185
 186 OS_INLINE
 187 UInt16
 188 OSSwapInt16(
 189     UInt16                        data
 190 )
 191 {
 192     UInt16 temp = data;
 193     return OSReadSwapInt16(&temp, 0);
 194 }
 195
 196 OS_INLINE
 197 UInt32
 198 OSSwapInt32(
 199     UInt32                        data
 200 )
 201 {
 202     UInt32 temp = data;
 203     return OSReadSwapInt32(&temp, 0);
 204 }
 205
 206 OS_INLINE
 207 UInt64
 208 OSSwapInt64(
 209     UInt64                        data
 210 )
 211 {
 212     UInt64 temp = data;
 213     return OSReadSwapInt64(&temp, 0);
 214 }
 215
 216 OS_INLINE
 217 UInt
 218 OSSwapInt(
 219     UInt                          data
 220 )
 221 {
 222     UInt temp = data;
 223     return OSReadSwapInt(&temp, 0);
 224 }
 225
 226 #endif /* ! _OS_OSBYTEORDERMACHINE_H */