libkern/libkern/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000-2005 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 #ifndef _OS_OSBYTEORDER_H
  24 #define _OS_OSBYTEORDER_H
  25
  26 #include <stdint.h>
  27
  28 /* Macros for swapping constant values in the preprocessing stage. */
  29 #define OSSwapConstInt16(x) \
  30     ((uint16_t)((((uint16_t)(x) & 0xff00) >> 8) | \
  31                 (((uint16_t)(x) & 0x00ff) << 8)))
  32
  33 #define OSSwapConstInt32(x) \
  34     ((uint32_t)((((uint32_t)(x) & 0xff000000) >> 24) | \
  35                 (((uint32_t)(x) & 0x00ff0000) >>  8) | \
  36                 (((uint32_t)(x) & 0x0000ff00) <<  8) | \
  37                 (((uint32_t)(x) & 0x000000ff) << 24)))
  38
  39 #define OSSwapConstInt64(x) \
  40     ((uint64_t)((((uint64_t)(x) & 0xff00000000000000ULL) >> 56) | \
  41                 (((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
  42                 (((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
  43                 (((uint64_t)(x) & 0x000000ff00000000ULL) >>  8) | \
  44                 (((uint64_t)(x) & 0x00000000ff000000ULL) <<  8) | \
  45                 (((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
  46                 (((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
  47                 (((uint64_t)(x) & 0x00000000000000ffULL) << 56)))
  48
  49 #if defined(__GNUC__)
  50
  51 #if (defined(__ppc__) || defined(__ppc64__))
  52 #include <libkern/ppc/OSByteOrder.h>
  53 #elif (defined(__i386__) || defined(__x86_64__))
  54 #include <libkern/i386/OSByteOrder.h>
  55 #else
  56 #include <libkern/machine/OSByteOrder.h>
  57 #endif
  58
  59 #define OSSwapInt16(x) \
  60     (__builtin_constant_p(x) ? OSSwapConstInt16(x) : _OSSwapInt16(x))
  61
  62 #define OSSwapInt32(x) \
  63     (__builtin_constant_p(x) ? OSSwapConstInt32(x) : _OSSwapInt32(x))
  64
  65 #define OSSwapInt64(x) \
  66     (__builtin_constant_p(x) ? OSSwapConstInt64(x) : _OSSwapInt64(x))
  67
  68 #else /* ! __GNUC__ */
  69
  70 #include <libkern/machine/OSByteOrder.h>
  71
  72 #define OSSwapInt16(x) OSSwapConstInt16(x)
  73
  74 #define OSSwapInt32(x) OSSwapConstInt32(x)
  75
  76 #define OSSwapInt64(x) OSSwapConstInt64(x)
  77
  78 #endif /* __GNUC__ */
  79
  80 enum {
  81     OSUnknownByteOrder,
  82     OSLittleEndian,
  83     OSBigEndian
  84 };
  85
  86 OS_INLINE
  87 int32_t
  88 OSHostByteOrder(void) {
  89 #if defined(__LITTLE_ENDIAN__)
  90     return OSLittleEndian;
  91 #elif defined(__BIG_ENDIAN__)
  92     return OSBigEndian;
  93 #else
  94     return OSUnknownByteOrder;
  95 #endif
  96 }
  97
  98 #define OSReadBigInt(x, y)              OSReadBigInt32(x, y)
  99 #define OSWriteBigInt(x, y, z)          OSWriteBigInt32(x, y, z)
 100 #define OSSwapBigToHostInt(x)           OSSwapBigToHostInt32(x)
 101 #define OSSwapHostToBigInt(x)           OSSwapHostToBigInt32(x)
 102 #define OSReadLittleInt(x, y)           OSReadLittleInt32(x, y)
 103 #define OSWriteLittleInt(x, y, z)       OSWriteLittleInt32(x, y, z)
 104 #define OSSwapHostToLittleInt(x)        OSSwapHostToLittleInt32(x)
 105 #define OSSwapLittleToHostInt(x)        OSSwapLittleToHostInt32(x)
 106
 107 /* Functions for loading native endian values. */
 108
 109 OS_INLINE
 110 uint16_t
 111 _OSReadInt16(
 112     const volatile void               * base,
 113     uintptr_t                     byteOffset
 114 )
 115 {
 116     return *(volatile uint16_t *)((uintptr_t)base + byteOffset);
 117 }
 118
 119 OS_INLINE
 120 uint32_t
 121 _OSReadInt32(
 122     const volatile void               * base,
 123     uintptr_t                     byteOffset
 124 )
 125 {
 126     return *(volatile uint32_t *)((uintptr_t)base + byteOffset);
 127 }
 128
 129 OS_INLINE
 130 uint64_t
 131 _OSReadInt64(
 132     const volatile void               * base,
 133     uintptr_t                     byteOffset
 134 )
 135 {
 136     return *(volatile uint64_t *)((uintptr_t)base + byteOffset);
 137 }
 138
 139 /* Functions for storing native endian values. */
 140
 141 OS_INLINE
 142 void
 143 _OSWriteInt16(
 144     volatile void               * base,
 145     uintptr_t                     byteOffset,
 146     uint16_t                      data
 147 )
 148 {
 149     *(volatile uint16_t *)((uintptr_t)base + byteOffset) = data;
 150 }
 151
 152 OS_INLINE
 153 void
 154 _OSWriteInt32(
 155     volatile void               * base,
 156     uintptr_t                     byteOffset,
 157     uint32_t                      data
 158 )
 159 {
 160     *(volatile uint32_t *)((uintptr_t)base + byteOffset) = data;
 161 }
 162
 163 OS_INLINE
 164 void
 165 _OSWriteInt64(
 166     volatile void               * base,
 167     uintptr_t                     byteOffset,
 168     uint64_t                      data
 169 )
 170 {
 171     *(volatile uint64_t *)((uintptr_t)base + byteOffset) = data;
 172 }
 173
 174 #if             defined(__BIG_ENDIAN__)
 175
 176 /* Functions for loading big endian to host endianess. */
 177
 178 #define OSReadBigInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 179 #define OSReadBigInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 180 #define OSReadBigInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 181
 182 /* Functions for storing host endianess to big endian. */
 183
 184 #define OSWriteBigInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 185 #define OSWriteBigInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 186 #define OSWriteBigInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 187
 188 /* Functions for loading little endian to host endianess. */
 189
 190 #define OSReadLittleInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 191 #define OSReadLittleInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 192 #define OSReadLittleInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 193
 194 /* Functions for storing host endianess to little endian. */
 195
 196 #define OSWriteLittleInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 197 #define OSWriteLittleInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 198 #define OSWriteLittleInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 199
 200 /* Host endianess to big endian byte swapping macros for constants. */
 201
 202 #define OSSwapHostToBigConstInt16(x) (x)
 203 #define OSSwapHostToBigConstInt32(x) (x)
 204 #define OSSwapHostToBigConstInt64(x) (x)
 205
 206 /* Generic host endianess to big endian byte swapping functions. */
 207
 208 #define OSSwapHostToBigInt16(x) ((uint16_t)(x))
 209 #define OSSwapHostToBigInt32(x) ((uint32_t)(x))
 210 #define OSSwapHostToBigInt64(x) ((uint64_t)(x))
 211
 212 /* Host endianess to little endian byte swapping macros for constants. */
 213
 214 #define OSSwapHostToLittleConstInt16(x) OSSwapConstInt16(x)
 215 #define OSSwapHostToLittleConstInt32(x) OSSwapConstInt32(x)
 216 #define OSSwapHostToLittleConstInt64(x) OSSwapConstInt64(x)
 217
 218 /* Generic host endianess to little endian byte swapping functions. */
 219
 220 #define OSSwapHostToLittleInt16(x) OSSwapInt16(x)
 221 #define OSSwapHostToLittleInt32(x) OSSwapInt32(x)
 222 #define OSSwapHostToLittleInt64(x) OSSwapInt64(x)
 223
 224 /* Big endian to host endianess byte swapping macros for constants. */
 225
 226 #define OSSwapBigToHostConstInt16(x) (x)
 227 #define OSSwapBigToHostConstInt32(x) (x)
 228 #define OSSwapBigToHostConstInt64(x) (x)
 229
 230 /* Generic big endian to host endianess byte swapping functions. */
 231
 232 #define OSSwapBigToHostInt16(x) ((uint16_t)(x))
 233 #define OSSwapBigToHostInt32(x) ((uint32_t)(x))
 234 #define OSSwapBigToHostInt64(x) ((uint64_t)(x))
 235
 236 /* Little endian to host endianess byte swapping macros for constants. */
 237
 238 #define OSSwapLittleToHostConstInt16(x) OSSwapConstInt16(x)
 239 #define OSSwapLittleToHostConstInt32(x) OSSwapConstInt32(x)
 240 #define OSSwapLittleToHostConstInt64(x) OSSwapConstInt64(x)
 241
 242 /* Generic little endian to host endianess byte swapping functions. */
 243
 244 #define OSSwapLittleToHostInt16(x) OSSwapInt16(x)
 245 #define OSSwapLittleToHostInt32(x) OSSwapInt32(x)
 246 #define OSSwapLittleToHostInt64(x) OSSwapInt64(x)
 247
 248 #elif           defined(__LITTLE_ENDIAN__)
 249
 250 /* Functions for loading big endian to host endianess. */
 251
 252 #define OSReadBigInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 253 #define OSReadBigInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 254 #define OSReadBigInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 255
 256 /* Functions for storing host endianess to big endian. */
 257
 258 #define OSWriteBigInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 259 #define OSWriteBigInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 260 #define OSWriteBigInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 261
 262 /* Functions for loading little endian to host endianess. */
 263
 264 #define OSReadLittleInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 265 #define OSReadLittleInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 266 #define OSReadLittleInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 267
 268 /* Functions for storing host endianess to little endian. */
 269
 270 #define OSWriteLittleInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 271 #define OSWriteLittleInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 272 #define OSWriteLittleInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 273
 274 /* Host endianess to big endian byte swapping macros for constants. */
 275
 276 #define OSSwapHostToBigConstInt16(x) OSSwapConstInt16(x)
 277 #define OSSwapHostToBigConstInt32(x) OSSwapConstInt32(x)
 278 #define OSSwapHostToBigConstInt64(x) OSSwapConstInt64(x)
 279
 280 /* Generic host endianess to big endian byte swapping functions. */
 281
 282 #define OSSwapHostToBigInt16(x) OSSwapInt16(x)
 283 #define OSSwapHostToBigInt32(x) OSSwapInt32(x)
 284 #define OSSwapHostToBigInt64(x) OSSwapInt64(x)
 285
 286 /* Host endianess to little endian byte swapping macros for constants. */
 287
 288 #define OSSwapHostToLittleConstInt16(x) (x)
 289 #define OSSwapHostToLittleConstInt32(x) (x)
 290 #define OSSwapHostToLittleConstInt64(x) (x)
 291
 292 /* Generic host endianess to little endian byte swapping functions. */
 293
 294 #define OSSwapHostToLittleInt16(x) ((uint16_t)(x))
 295 #define OSSwapHostToLittleInt32(x) ((uint32_t)(x))
 296 #define OSSwapHostToLittleInt64(x) ((uint64_t)(x))
 297
 298 /* Big endian to host endianess byte swapping macros for constants. */
 299
 300 #define OSSwapBigToHostConstInt16(x) OSSwapConstInt16(x)
 301 #define OSSwapBigToHostConstInt32(x) OSSwapConstInt32(x)
 302 #define OSSwapBigToHostConstInt64(x) OSSwapConstInt64(x)
 303
 304 /* Generic big endian to host endianess byte swapping functions. */
 305
 306 #define OSSwapBigToHostInt16(x) OSSwapInt16(x)
 307 #define OSSwapBigToHostInt32(x) OSSwapInt32(x)
 308 #define OSSwapBigToHostInt64(x) OSSwapInt64(x)
 309
 310 /* Little endian to host endianess byte swapping macros for constants. */
 311
 312 #define OSSwapLittleToHostConstInt16(x) (x)
 313 #define OSSwapLittleToHostConstInt32(x) (x)
 314 #define OSSwapLittleToHostConstInt64(x) (x)
 315
 316 /* Generic little endian to host endianess byte swapping functions. */
 317
 318 #define OSSwapLittleToHostInt16(x) ((uint16_t)(x))
 319 #define OSSwapLittleToHostInt32(x) ((uint32_t)(x))
 320 #define OSSwapLittleToHostInt64(x) ((uint64_t)(x))
 321
 322 #else
 323 #error Unknown endianess.
 324 #endif
 325
 326 #endif /* ! _OS_OSBYTEORDER_H */
 327
 328