libkern/libkern/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #ifndef _OS_OSBYTEORDER_H
  30 #define _OS_OSBYTEORDER_H
  31
  32 #include <stdint.h>
  33
  34 /* Macros for swapping constant values in the preprocessing stage. */
  35 #define OSSwapConstInt16(x) \
  36     ((uint16_t)((((uint16_t)(x) & 0xff00) >> 8) | \
  37                 (((uint16_t)(x) & 0x00ff) << 8)))
  38
  39 #define OSSwapConstInt32(x) \
  40     ((uint32_t)((((uint32_t)(x) & 0xff000000) >> 24) | \
  41                 (((uint32_t)(x) & 0x00ff0000) >>  8) | \
  42                 (((uint32_t)(x) & 0x0000ff00) <<  8) | \
  43                 (((uint32_t)(x) & 0x000000ff) << 24)))
  44
  45 #define OSSwapConstInt64(x) \
  46     ((uint64_t)((((uint64_t)(x) & 0xff00000000000000ULL) >> 56) | \
  47                 (((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
  48                 (((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
  49                 (((uint64_t)(x) & 0x000000ff00000000ULL) >>  8) | \
  50                 (((uint64_t)(x) & 0x00000000ff000000ULL) <<  8) | \
  51                 (((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
  52                 (((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
  53                 (((uint64_t)(x) & 0x00000000000000ffULL) << 56)))
  54
  55 #if defined(__GNUC__)
  56
  57 #if (defined(__ppc__) || defined(__ppc64__))
  58 #include <libkern/ppc/OSByteOrder.h>
  59 #elif (defined(__i386__) || defined(__x86_64__))
  60 #include <libkern/i386/OSByteOrder.h>
  61 #else
  62 #include <libkern/machine/OSByteOrder.h>
  63 #endif
  64
  65 #define OSSwapInt16(x) \
  66     (__builtin_constant_p(x) ? OSSwapConstInt16(x) : _OSSwapInt16(x))
  67
  68 #define OSSwapInt32(x) \
  69     (__builtin_constant_p(x) ? OSSwapConstInt32(x) : _OSSwapInt32(x))
  70
  71 #define OSSwapInt64(x) \
  72     (__builtin_constant_p(x) ? OSSwapConstInt64(x) : _OSSwapInt64(x))
  73
  74 #else /* ! __GNUC__ */
  75
  76 #include <libkern/machine/OSByteOrder.h>
  77
  78 #define OSSwapInt16(x) OSSwapConstInt16(x)
  79
  80 #define OSSwapInt32(x) OSSwapConstInt32(x)
  81
  82 #define OSSwapInt64(x) OSSwapConstInt64(x)
  83
  84 #endif /* __GNUC__ */
  85
  86 enum {
  87     OSUnknownByteOrder,
  88     OSLittleEndian,
  89     OSBigEndian
  90 };
  91
  92 OS_INLINE
  93 int32_t
  94 OSHostByteOrder(void) {
  95 #if defined(__LITTLE_ENDIAN__)
  96     return OSLittleEndian;
  97 #elif defined(__BIG_ENDIAN__)
  98     return OSBigEndian;
  99 #else
 100     return OSUnknownByteOrder;
 101 #endif
 102 }
 103
 104 #define OSReadBigInt(x, y)              OSReadBigInt32(x, y)
 105 #define OSWriteBigInt(x, y, z)          OSWriteBigInt32(x, y, z)
 106 #define OSSwapBigToHostInt(x)           OSSwapBigToHostInt32(x)
 107 #define OSSwapHostToBigInt(x)           OSSwapHostToBigInt32(x)
 108 #define OSReadLittleInt(x, y)           OSReadLittleInt32(x, y)
 109 #define OSWriteLittleInt(x, y, z)       OSWriteLittleInt32(x, y, z)
 110 #define OSSwapHostToLittleInt(x)        OSSwapHostToLittleInt32(x)
 111 #define OSSwapLittleToHostInt(x)        OSSwapLittleToHostInt32(x)
 112
 113 /* Functions for loading native endian values. */
 114
 115 OS_INLINE
 116 uint16_t
 117 _OSReadInt16(
 118     const volatile void               * base,
 119     uintptr_t                     byteOffset
 120 )
 121 {
 122     return *(volatile uint16_t *)((uintptr_t)base + byteOffset);
 123 }
 124
 125 OS_INLINE
 126 uint32_t
 127 _OSReadInt32(
 128     const volatile void               * base,
 129     uintptr_t                     byteOffset
 130 )
 131 {
 132     return *(volatile uint32_t *)((uintptr_t)base + byteOffset);
 133 }
 134
 135 OS_INLINE
 136 uint64_t
 137 _OSReadInt64(
 138     const volatile void               * base,
 139     uintptr_t                     byteOffset
 140 )
 141 {
 142     return *(volatile uint64_t *)((uintptr_t)base + byteOffset);
 143 }
 144
 145 /* Functions for storing native endian values. */
 146
 147 OS_INLINE
 148 void
 149 _OSWriteInt16(
 150     volatile void               * base,
 151     uintptr_t                     byteOffset,
 152     uint16_t                      data
 153 )
 154 {
 155     *(volatile uint16_t *)((uintptr_t)base + byteOffset) = data;
 156 }
 157
 158 OS_INLINE
 159 void
 160 _OSWriteInt32(
 161     volatile void               * base,
 162     uintptr_t                     byteOffset,
 163     uint32_t                      data
 164 )
 165 {
 166     *(volatile uint32_t *)((uintptr_t)base + byteOffset) = data;
 167 }
 168
 169 OS_INLINE
 170 void
 171 _OSWriteInt64(
 172     volatile void               * base,
 173     uintptr_t                     byteOffset,
 174     uint64_t                      data
 175 )
 176 {
 177     *(volatile uint64_t *)((uintptr_t)base + byteOffset) = data;
 178 }
 179
 180 #if             defined(__BIG_ENDIAN__)
 181
 182 /* Functions for loading big endian to host endianess. */
 183
 184 #define OSReadBigInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 185 #define OSReadBigInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 186 #define OSReadBigInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 187
 188 /* Functions for storing host endianess to big endian. */
 189
 190 #define OSWriteBigInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 191 #define OSWriteBigInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 192 #define OSWriteBigInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 193
 194 /* Functions for loading little endian to host endianess. */
 195
 196 #define OSReadLittleInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 197 #define OSReadLittleInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 198 #define OSReadLittleInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 199
 200 /* Functions for storing host endianess to little endian. */
 201
 202 #define OSWriteLittleInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 203 #define OSWriteLittleInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 204 #define OSWriteLittleInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 205
 206 /* Host endianess to big endian byte swapping macros for constants. */
 207
 208 #define OSSwapHostToBigConstInt16(x) (x)
 209 #define OSSwapHostToBigConstInt32(x) (x)
 210 #define OSSwapHostToBigConstInt64(x) (x)
 211
 212 /* Generic host endianess to big endian byte swapping functions. */
 213
 214 #define OSSwapHostToBigInt16(x) ((uint16_t)(x))
 215 #define OSSwapHostToBigInt32(x) ((uint32_t)(x))
 216 #define OSSwapHostToBigInt64(x) ((uint64_t)(x))
 217
 218 /* Host endianess to little endian byte swapping macros for constants. */
 219
 220 #define OSSwapHostToLittleConstInt16(x) OSSwapConstInt16(x)
 221 #define OSSwapHostToLittleConstInt32(x) OSSwapConstInt32(x)
 222 #define OSSwapHostToLittleConstInt64(x) OSSwapConstInt64(x)
 223
 224 /* Generic host endianess to little endian byte swapping functions. */
 225
 226 #define OSSwapHostToLittleInt16(x) OSSwapInt16(x)
 227 #define OSSwapHostToLittleInt32(x) OSSwapInt32(x)
 228 #define OSSwapHostToLittleInt64(x) OSSwapInt64(x)
 229
 230 /* Big endian to host endianess byte swapping macros for constants. */
 231
 232 #define OSSwapBigToHostConstInt16(x) (x)
 233 #define OSSwapBigToHostConstInt32(x) (x)
 234 #define OSSwapBigToHostConstInt64(x) (x)
 235
 236 /* Generic big endian to host endianess byte swapping functions. */
 237
 238 #define OSSwapBigToHostInt16(x) ((uint16_t)(x))
 239 #define OSSwapBigToHostInt32(x) ((uint32_t)(x))
 240 #define OSSwapBigToHostInt64(x) ((uint64_t)(x))
 241
 242 /* Little endian to host endianess byte swapping macros for constants. */
 243
 244 #define OSSwapLittleToHostConstInt16(x) OSSwapConstInt16(x)
 245 #define OSSwapLittleToHostConstInt32(x) OSSwapConstInt32(x)
 246 #define OSSwapLittleToHostConstInt64(x) OSSwapConstInt64(x)
 247
 248 /* Generic little endian to host endianess byte swapping functions. */
 249
 250 #define OSSwapLittleToHostInt16(x) OSSwapInt16(x)
 251 #define OSSwapLittleToHostInt32(x) OSSwapInt32(x)
 252 #define OSSwapLittleToHostInt64(x) OSSwapInt64(x)
 253
 254 #elif           defined(__LITTLE_ENDIAN__)
 255
 256 /* Functions for loading big endian to host endianess. */
 257
 258 #define OSReadBigInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 259 #define OSReadBigInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 260 #define OSReadBigInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 261
 262 /* Functions for storing host endianess to big endian. */
 263
 264 #define OSWriteBigInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 265 #define OSWriteBigInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 266 #define OSWriteBigInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 267
 268 /* Functions for loading little endian to host endianess. */
 269
 270 #define OSReadLittleInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 271 #define OSReadLittleInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 272 #define OSReadLittleInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 273
 274 /* Functions for storing host endianess to little endian. */
 275
 276 #define OSWriteLittleInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 277 #define OSWriteLittleInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 278 #define OSWriteLittleInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 279
 280 /* Host endianess to big endian byte swapping macros for constants. */
 281
 282 #define OSSwapHostToBigConstInt16(x) OSSwapConstInt16(x)
 283 #define OSSwapHostToBigConstInt32(x) OSSwapConstInt32(x)
 284 #define OSSwapHostToBigConstInt64(x) OSSwapConstInt64(x)
 285
 286 /* Generic host endianess to big endian byte swapping functions. */
 287
 288 #define OSSwapHostToBigInt16(x) OSSwapInt16(x)
 289 #define OSSwapHostToBigInt32(x) OSSwapInt32(x)
 290 #define OSSwapHostToBigInt64(x) OSSwapInt64(x)
 291
 292 /* Host endianess to little endian byte swapping macros for constants. */
 293
 294 #define OSSwapHostToLittleConstInt16(x) (x)
 295 #define OSSwapHostToLittleConstInt32(x) (x)
 296 #define OSSwapHostToLittleConstInt64(x) (x)
 297
 298 /* Generic host endianess to little endian byte swapping functions. */
 299
 300 #define OSSwapHostToLittleInt16(x) ((uint16_t)(x))
 301 #define OSSwapHostToLittleInt32(x) ((uint32_t)(x))
 302 #define OSSwapHostToLittleInt64(x) ((uint64_t)(x))
 303
 304 /* Big endian to host endianess byte swapping macros for constants. */
 305
 306 #define OSSwapBigToHostConstInt16(x) OSSwapConstInt16(x)
 307 #define OSSwapBigToHostConstInt32(x) OSSwapConstInt32(x)
 308 #define OSSwapBigToHostConstInt64(x) OSSwapConstInt64(x)
 309
 310 /* Generic big endian to host endianess byte swapping functions. */
 311
 312 #define OSSwapBigToHostInt16(x) OSSwapInt16(x)
 313 #define OSSwapBigToHostInt32(x) OSSwapInt32(x)
 314 #define OSSwapBigToHostInt64(x) OSSwapInt64(x)
 315
 316 /* Little endian to host endianess byte swapping macros for constants. */
 317
 318 #define OSSwapLittleToHostConstInt16(x) (x)
 319 #define OSSwapLittleToHostConstInt32(x) (x)
 320 #define OSSwapLittleToHostConstInt64(x) (x)
 321
 322 /* Generic little endian to host endianess byte swapping functions. */
 323
 324 #define OSSwapLittleToHostInt16(x) ((uint16_t)(x))
 325 #define OSSwapLittleToHostInt32(x) ((uint32_t)(x))
 326 #define OSSwapLittleToHostInt64(x) ((uint64_t)(x))
 327
 328 #else
 329 #error Unknown endianess.
 330 #endif
 331
 332 #endif /* ! _OS_OSBYTEORDER_H */
 333
 334