libkern/libkern/c++/OSEndianTypes.h

   1 /*
   2  * Copyright (c) 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  * HISTORY
  23  *   gvdl    20050620    Created
  24  */
  25
  26 /*!
  27 @header OSEndianTypes
  28 @abstract C++ inline types for byte swapping
  29 @discussion
  30 The OSEndianTypes consist of a number of types that are used very similarly to the traditional MacOS C scalar integers types, eg. UInt32 and SInt32.
  31 @copyright 2005 Apple Computer, Inc. All rights reserved.
  32 @updated 2005-07-25
  33 */
  34
  35 // Header doc magic trick for simple documentation
  36 #if 0
  37 /*!  @typedef BigUInt16
  38 @abstract A Big-endian unsigned integer scalar size 16 - UInt16 */
  39 typedef class BigUInt16 BigUInt16;
  40 #endif
  41
  42 #if 0
  43 /*! @typedef BigSInt16
  44 @abstract A Big-endian signed integer scalar size 16 - SInt16 */
  45 typedef class BigSInt16 BigSInt16;
  46
  47 /*! @typedef BigUInt32
  48 @abstract A Big-endian unsigned integer scalar size 32 - UInt32 */
  49 typedef class BigUInt32 BigUInt32;
  50
  51 /*! @typedef BigSInt32
  52 @abstract A Big-endian signed integer scalar size 32 - SInt32 */
  53 typedef class BigSInt32 BigSInt32;
  54
  55 /*! @typedef BigUInt64
  56 @abstract A Big-endian unsigned integer scalar size 64 - UInt64 */
  57 typedef class BigUInt64 BigUInt64;
  58
  59 /*! @typedef BigSInt64
  60 @abstract A Big-endian signed integer scalar size 64 - SInt64 */
  61 typedef class BigSInt64 BigSInt64;
  62
  63 /*! @typedef LittleUInt16
  64 @abstract A Little-endian unsigned integer scalar size 16 - UInt16 */
  65 typedef class LittleUInt16 LittleUInt16;
  66
  67 /*! @typedef LittleSInt16
  68 @abstract A Little-endian signed integer scalar size 16 - SInt16 */
  69 typedef class LittleSInt16 LittleSInt16;
  70
  71 /*! @typedef LittleUInt32
  72 @abstract A Little-endian unsigned integer scalar size 32 - UInt32 */
  73 typedef class LittleUInt32 LittleUInt32;
  74
  75 /*! @typedef LittleSInt32
  76 @abstract A Little-endian signed integer scalar size 32 - SInt32 */
  77 typedef class LittleSInt32 LittleSInt32;
  78
  79 /*! @typedef LittleUInt64
  80 @abstract A Little-endian unsigned integer scalar size 64 - UInt64 */
  81 typedef class LittleUInt64 LittleUInt64;
  82
  83 /*! @typedef LittleSInt64
  84 @abstract A Little-endian signed integer scalar size 64 - SInt64 */
  85 typedef class LittleSInt64 LittleSInt64;
  86
  87 */
  88 #endif
  89
  90 #ifndef _OS_OSENDIANHELPER_H
  91 #define _OS_OSENDIANHELPER_H
  92
  93 #if __cplusplus
  94
  95 #include <libkern/OSTypes.h>
  96 #include <libkern/OSByteOrder.h>
  97
  98 // Probably should really be using templates, this is one of the few cases
  99 // where they do make sense.  But as the kernel is not allowed to export
 100 // template based C++ APIs we have to use sophisticated macros instead
 101 #define __OSEndianSignIntSizeDEF(argname, argend, argtype, argsize) {   \
 102 public:                                                                 \
 103     typedef argtype ## argsize          Value;                          \
 104                                                                         \
 105 private:                                                                \
 106     typedef UInt ## argsize             UValue;                         \
 107     UValue mValue;                                                      \
 108                                                                         \
 109     void writeValue(Value v) {                                          \
 110         if (__builtin_constant_p(v))                                    \
 111             mValue = OSSwapHostTo ## argend ## ConstInt ## argsize(v);  \
 112         else                                                            \
 113             OSWrite ## argend ## Int ## argsize(&mValue, 0, (UValue) v);\
 114     };                                                                  \
 115                                                                         \
 116     Value readValue() const {                                           \
 117         return (Value) OSRead ## argend ## Int ## argsize(&mValue, 0);  \
 118     };                                                                  \
 119                                                                         \
 120 public:                                                                 \
 121     argname() { };                                                      \
 122                                                                         \
 123     argname (Value v) { writeValue(v); };                               \
 124     argname  &operator = (Value v) { writeValue(v); return *this; }     \
 125                                                                         \
 126     Value get() const { return readValue(); };                          \
 127     operator Value () const { return readValue(); };                    \
 128 }
 129
 130 class BigUInt16    __OSEndianSignIntSizeDEF(BigUInt16,    Big,    UInt, 16);
 131 class BigSInt16    __OSEndianSignIntSizeDEF(BigSInt16,    Big,    SInt, 16);
 132 class BigUInt32    __OSEndianSignIntSizeDEF(BigUInt32,    Big,    UInt, 32);
 133 class BigSInt32    __OSEndianSignIntSizeDEF(BigSInt32,    Big,    SInt, 32);
 134 class BigUInt64    __OSEndianSignIntSizeDEF(BigUInt64,    Big,    UInt, 64);
 135 class BigSInt64    __OSEndianSignIntSizeDEF(BigSInt64,    Big,    SInt, 64);
 136 class LittleUInt16 __OSEndianSignIntSizeDEF(LittleUInt16, Little, UInt, 16);
 137 class LittleSInt16 __OSEndianSignIntSizeDEF(LittleSInt16, Little, SInt, 16);
 138 class LittleUInt32 __OSEndianSignIntSizeDEF(LittleUInt32, Little, UInt, 32);
 139 class LittleSInt32 __OSEndianSignIntSizeDEF(LittleSInt32, Little, SInt, 32);
 140 class LittleUInt64 __OSEndianSignIntSizeDEF(LittleUInt64, Little, UInt, 64);
 141 class LittleSInt64 __OSEndianSignIntSizeDEF(LittleSInt64, Little, SInt, 64);
 142
 143 #undef __OSEndianSignIntSizeDEF
 144
 145 #endif /* __cplusplus */
 146
 147 #endif /* ! _OS_OSENDIANHELPER_H */
 148
 149