libkern/libkern/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 #ifndef _OS_OSBYTEORDER_H
  32 #define _OS_OSBYTEORDER_H
  33
  34 #include <stdint.h>
  35
  36 /* Macros for swapping constant values in the preprocessing stage. */
  37 #define OSSwapConstInt16(x) \
  38     ((uint16_t)((((uint16_t)(x) & 0xff00) >> 8) | \
  39                 (((uint16_t)(x) & 0x00ff) << 8)))
  40
  41 #define OSSwapConstInt32(x) \
  42     ((uint32_t)((((uint32_t)(x) & 0xff000000) >> 24) | \
  43                 (((uint32_t)(x) & 0x00ff0000) >>  8) | \
  44                 (((uint32_t)(x) & 0x0000ff00) <<  8) | \
  45                 (((uint32_t)(x) & 0x000000ff) << 24)))
  46
  47 #define OSSwapConstInt64(x) \
  48     ((uint64_t)((((uint64_t)(x) & 0xff00000000000000ULL) >> 56) | \
  49                 (((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
  50                 (((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
  51                 (((uint64_t)(x) & 0x000000ff00000000ULL) >>  8) | \
  52                 (((uint64_t)(x) & 0x00000000ff000000ULL) <<  8) | \
  53                 (((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
  54                 (((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
  55                 (((uint64_t)(x) & 0x00000000000000ffULL) << 56)))
  56
  57 #if defined(__GNUC__)
  58
  59 #if (defined(__ppc__) || defined(__ppc64__))
  60 #include <libkern/ppc/OSByteOrder.h>
  61 #elif (defined(__i386__) || defined(__x86_64__))
  62 #include <libkern/i386/OSByteOrder.h>
  63 #else
  64 #include <libkern/machine/OSByteOrder.h>
  65 #endif
  66
  67 #define OSSwapInt16(x) \
  68     (__builtin_constant_p(x) ? OSSwapConstInt16(x) : _OSSwapInt16(x))
  69
  70 #define OSSwapInt32(x) \
  71     (__builtin_constant_p(x) ? OSSwapConstInt32(x) : _OSSwapInt32(x))
  72
  73 #define OSSwapInt64(x) \
  74     (__builtin_constant_p(x) ? OSSwapConstInt64(x) : _OSSwapInt64(x))
  75
  76 #else /* ! __GNUC__ */
  77
  78 #include <libkern/machine/OSByteOrder.h>
  79
  80 #define OSSwapInt16(x) OSSwapConstInt16(x)
  81
  82 #define OSSwapInt32(x) OSSwapConstInt32(x)
  83
  84 #define OSSwapInt64(x) OSSwapConstInt64(x)
  85
  86 #endif /* __GNUC__ */
  87
  88 enum {
  89     OSUnknownByteOrder,
  90     OSLittleEndian,
  91     OSBigEndian
  92 };
  93
  94 OS_INLINE
  95 int32_t
  96 OSHostByteOrder(void) {
  97 #if defined(__LITTLE_ENDIAN__)
  98     return OSLittleEndian;
  99 #elif defined(__BIG_ENDIAN__)
 100     return OSBigEndian;
 101 #else
 102     return OSUnknownByteOrder;
 103 #endif
 104 }
 105
 106 #define OSReadBigInt(x, y)              OSReadBigInt32(x, y)
 107 #define OSWriteBigInt(x, y, z)          OSWriteBigInt32(x, y, z)
 108 #define OSSwapBigToHostInt(x)           OSSwapBigToHostInt32(x)
 109 #define OSSwapHostToBigInt(x)           OSSwapHostToBigInt32(x)
 110 #define OSReadLittleInt(x, y)           OSReadLittleInt32(x, y)
 111 #define OSWriteLittleInt(x, y, z)       OSWriteLittleInt32(x, y, z)
 112 #define OSSwapHostToLittleInt(x)        OSSwapHostToLittleInt32(x)
 113 #define OSSwapLittleToHostInt(x)        OSSwapLittleToHostInt32(x)
 114
 115 /* Functions for loading native endian values. */
 116
 117 OS_INLINE
 118 uint16_t
 119 _OSReadInt16(
 120     const volatile void               * base,
 121     uintptr_t                     byteOffset
 122 )
 123 {
 124     return *(volatile uint16_t *)((uintptr_t)base + byteOffset);
 125 }
 126
 127 OS_INLINE
 128 uint32_t
 129 _OSReadInt32(
 130     const volatile void               * base,
 131     uintptr_t                     byteOffset
 132 )
 133 {
 134     return *(volatile uint32_t *)((uintptr_t)base + byteOffset);
 135 }
 136
 137 OS_INLINE
 138 uint64_t
 139 _OSReadInt64(
 140     const volatile void               * base,
 141     uintptr_t                     byteOffset
 142 )
 143 {
 144     return *(volatile uint64_t *)((uintptr_t)base + byteOffset);
 145 }
 146
 147 /* Functions for storing native endian values. */
 148
 149 OS_INLINE
 150 void
 151 _OSWriteInt16(
 152     volatile void               * base,
 153     uintptr_t                     byteOffset,
 154     uint16_t                      data
 155 )
 156 {
 157     *(volatile uint16_t *)((uintptr_t)base + byteOffset) = data;
 158 }
 159
 160 OS_INLINE
 161 void
 162 _OSWriteInt32(
 163     volatile void               * base,
 164     uintptr_t                     byteOffset,
 165     uint32_t                      data
 166 )
 167 {
 168     *(volatile uint32_t *)((uintptr_t)base + byteOffset) = data;
 169 }
 170
 171 OS_INLINE
 172 void
 173 _OSWriteInt64(
 174     volatile void               * base,
 175     uintptr_t                     byteOffset,
 176     uint64_t                      data
 177 )
 178 {
 179     *(volatile uint64_t *)((uintptr_t)base + byteOffset) = data;
 180 }
 181
 182 #if             defined(__BIG_ENDIAN__)
 183
 184 /* Functions for loading big endian to host endianess. */
 185
 186 #define OSReadBigInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 187 #define OSReadBigInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 188 #define OSReadBigInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 189
 190 /* Functions for storing host endianess to big endian. */
 191
 192 #define OSWriteBigInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 193 #define OSWriteBigInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 194 #define OSWriteBigInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 195
 196 /* Functions for loading little endian to host endianess. */
 197
 198 #define OSReadLittleInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 199 #define OSReadLittleInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 200 #define OSReadLittleInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 201
 202 /* Functions for storing host endianess to little endian. */
 203
 204 #define OSWriteLittleInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 205 #define OSWriteLittleInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 206 #define OSWriteLittleInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 207
 208 /* Host endianess to big endian byte swapping macros for constants. */
 209
 210 #define OSSwapHostToBigConstInt16(x) (x)
 211 #define OSSwapHostToBigConstInt32(x) (x)
 212 #define OSSwapHostToBigConstInt64(x) (x)
 213
 214 /* Generic host endianess to big endian byte swapping functions. */
 215
 216 #define OSSwapHostToBigInt16(x) ((uint16_t)(x))
 217 #define OSSwapHostToBigInt32(x) ((uint32_t)(x))
 218 #define OSSwapHostToBigInt64(x) ((uint64_t)(x))
 219
 220 /* Host endianess to little endian byte swapping macros for constants. */
 221
 222 #define OSSwapHostToLittleConstInt16(x) OSSwapConstInt16(x)
 223 #define OSSwapHostToLittleConstInt32(x) OSSwapConstInt32(x)
 224 #define OSSwapHostToLittleConstInt64(x) OSSwapConstInt64(x)
 225
 226 /* Generic host endianess to little endian byte swapping functions. */
 227
 228 #define OSSwapHostToLittleInt16(x) OSSwapInt16(x)
 229 #define OSSwapHostToLittleInt32(x) OSSwapInt32(x)
 230 #define OSSwapHostToLittleInt64(x) OSSwapInt64(x)
 231
 232 /* Big endian to host endianess byte swapping macros for constants. */
 233
 234 #define OSSwapBigToHostConstInt16(x) (x)
 235 #define OSSwapBigToHostConstInt32(x) (x)
 236 #define OSSwapBigToHostConstInt64(x) (x)
 237
 238 /* Generic big endian to host endianess byte swapping functions. */
 239
 240 #define OSSwapBigToHostInt16(x) ((uint16_t)(x))
 241 #define OSSwapBigToHostInt32(x) ((uint32_t)(x))
 242 #define OSSwapBigToHostInt64(x) ((uint64_t)(x))
 243
 244 /* Little endian to host endianess byte swapping macros for constants. */
 245
 246 #define OSSwapLittleToHostConstInt16(x) OSSwapConstInt16(x)
 247 #define OSSwapLittleToHostConstInt32(x) OSSwapConstInt32(x)
 248 #define OSSwapLittleToHostConstInt64(x) OSSwapConstInt64(x)
 249
 250 /* Generic little endian to host endianess byte swapping functions. */
 251
 252 #define OSSwapLittleToHostInt16(x) OSSwapInt16(x)
 253 #define OSSwapLittleToHostInt32(x) OSSwapInt32(x)
 254 #define OSSwapLittleToHostInt64(x) OSSwapInt64(x)
 255
 256 #elif           defined(__LITTLE_ENDIAN__)
 257
 258 /* Functions for loading big endian to host endianess. */
 259
 260 #define OSReadBigInt16(base, byteOffset) OSReadSwapInt16(base, byteOffset)
 261 #define OSReadBigInt32(base, byteOffset) OSReadSwapInt32(base, byteOffset)
 262 #define OSReadBigInt64(base, byteOffset) OSReadSwapInt64(base, byteOffset)
 263
 264 /* Functions for storing host endianess to big endian. */
 265
 266 #define OSWriteBigInt16(base, byteOffset, data) OSWriteSwapInt16(base, byteOffset, data)
 267 #define OSWriteBigInt32(base, byteOffset, data) OSWriteSwapInt32(base, byteOffset, data)
 268 #define OSWriteBigInt64(base, byteOffset, data) OSWriteSwapInt64(base, byteOffset, data)
 269
 270 /* Functions for loading little endian to host endianess. */
 271
 272 #define OSReadLittleInt16(base, byteOffset) _OSReadInt16(base, byteOffset)
 273 #define OSReadLittleInt32(base, byteOffset) _OSReadInt32(base, byteOffset)
 274 #define OSReadLittleInt64(base, byteOffset) _OSReadInt64(base, byteOffset)
 275
 276 /* Functions for storing host endianess to little endian. */
 277
 278 #define OSWriteLittleInt16(base, byteOffset, data) _OSWriteInt16(base, byteOffset, data)
 279 #define OSWriteLittleInt32(base, byteOffset, data) _OSWriteInt32(base, byteOffset, data)
 280 #define OSWriteLittleInt64(base, byteOffset, data) _OSWriteInt64(base, byteOffset, data)
 281
 282 /* Host endianess to big endian byte swapping macros for constants. */
 283
 284 #define OSSwapHostToBigConstInt16(x) OSSwapConstInt16(x)
 285 #define OSSwapHostToBigConstInt32(x) OSSwapConstInt32(x)
 286 #define OSSwapHostToBigConstInt64(x) OSSwapConstInt64(x)
 287
 288 /* Generic host endianess to big endian byte swapping functions. */
 289
 290 #define OSSwapHostToBigInt16(x) OSSwapInt16(x)
 291 #define OSSwapHostToBigInt32(x) OSSwapInt32(x)
 292 #define OSSwapHostToBigInt64(x) OSSwapInt64(x)
 293
 294 /* Host endianess to little endian byte swapping macros for constants. */
 295
 296 #define OSSwapHostToLittleConstInt16(x) (x)
 297 #define OSSwapHostToLittleConstInt32(x) (x)
 298 #define OSSwapHostToLittleConstInt64(x) (x)
 299
 300 /* Generic host endianess to little endian byte swapping functions. */
 301
 302 #define OSSwapHostToLittleInt16(x) ((uint16_t)(x))
 303 #define OSSwapHostToLittleInt32(x) ((uint32_t)(x))
 304 #define OSSwapHostToLittleInt64(x) ((uint64_t)(x))
 305
 306 /* Big endian to host endianess byte swapping macros for constants. */
 307
 308 #define OSSwapBigToHostConstInt16(x) OSSwapConstInt16(x)
 309 #define OSSwapBigToHostConstInt32(x) OSSwapConstInt32(x)
 310 #define OSSwapBigToHostConstInt64(x) OSSwapConstInt64(x)
 311
 312 /* Generic big endian to host endianess byte swapping functions. */
 313
 314 #define OSSwapBigToHostInt16(x) OSSwapInt16(x)
 315 #define OSSwapBigToHostInt32(x) OSSwapInt32(x)
 316 #define OSSwapBigToHostInt64(x) OSSwapInt64(x)
 317
 318 /* Little endian to host endianess byte swapping macros for constants. */
 319
 320 #define OSSwapLittleToHostConstInt16(x) (x)
 321 #define OSSwapLittleToHostConstInt32(x) (x)
 322 #define OSSwapLittleToHostConstInt64(x) (x)
 323
 324 /* Generic little endian to host endianess byte swapping functions. */
 325
 326 #define OSSwapLittleToHostInt16(x) ((uint16_t)(x))
 327 #define OSSwapLittleToHostInt32(x) ((uint32_t)(x))
 328 #define OSSwapLittleToHostInt64(x) ((uint64_t)(x))
 329
 330 #else
 331 #error Unknown endianess.
 332 #endif
 333
 334 #endif /* ! _OS_OSBYTEORDER_H */
 335
 336