OSX/libsecurity_utilities/lib/endian.h

   1 /*
   2  * Copyright (c) 2002-2004,2011-2012,2014 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24
  25 /*
  26  * cssm utilities
  27  */
  28 #ifndef _H_ENDIAN
  29 #define _H_ENDIAN
  30
  31 #include <machine/endian.h>
  32 #include <libkern/OSByteOrder.h>
  33 #include <security_utilities/utilities.h>
  34 #include <security_utilities/memutils.h>
  35 #include <security_utilities/debugging.h>
  36
  37 namespace Security {
  38
  39
  40 //
  41 // Encode/decode operations by type, overloaded.
  42 // You can use these functions directly, but consider using
  43 // the higher-level constructs below instead.
  44 //
  45 #ifdef __LP64__
  46 static inline unsigned long h2n(unsigned long v) { return OSSwapHostToBigInt64(v); }
  47 static inline unsigned long n2h(unsigned long v) { return OSSwapBigToHostInt64(v); }
  48 static inline unsigned long flip(unsigned long v) { return OSSwapInt64(v); }
  49 static inline signed long h2n(signed long v) { return OSSwapHostToBigInt64(v); }
  50 static inline signed long n2h(signed long v) { return OSSwapBigToHostInt64(v); }
  51 static inline signed long flip(signed long v) { return OSSwapInt64(v); }
  52 #else
  53 static inline unsigned long h2n(unsigned long v)        { return htonl(v); }
  54 static inline unsigned long n2h(unsigned long v)        { return ntohl(v); }
  55 static inline unsigned long flip(unsigned long v)       { return OSSwapInt32(v); }
  56 static inline signed long h2n(signed long v)            { return htonl(v); }
  57 static inline signed long n2h(signed long v)            { return ntohl(v); }
  58 static inline signed long flip(signed long v)           { return OSSwapInt32(v); }
  59 #endif
  60
  61 static inline unsigned long long h2n(unsigned long long v) { return OSSwapHostToBigInt64(v); }
  62 static inline unsigned long long n2h(unsigned long long v) { return OSSwapBigToHostInt64(v); }
  63 static inline unsigned long long flip(unsigned long long v) { return OSSwapInt64(v); }
  64 static inline long long h2n(long long v)                        { return OSSwapHostToBigInt64(v); }
  65 static inline long long n2h(long long v)                        { return OSSwapBigToHostInt64(v); }
  66 static inline long long flip(long long v)                       { return OSSwapInt64(v); }
  67
  68 static inline unsigned int h2n(unsigned int v)          { return htonl(v); }
  69 static inline unsigned int n2h(unsigned int v)          { return ntohl(v); }
  70 static inline unsigned int flip(unsigned int v)         { return OSSwapInt32(v); }
  71 static inline signed int h2n(int v)                                     { return htonl(v); }
  72 static inline signed int n2h(int v)                                     { return ntohl(v); }
  73 static inline signed int flip(int v)                            { return OSSwapInt32(v); }
  74
  75 static inline unsigned short h2n(unsigned short v)      { return htons(v); }
  76 static inline unsigned short n2h(unsigned short v)      { return ntohs(v); }
  77 static inline unsigned short flip(unsigned short v)     { return OSSwapInt16(v); }
  78 static inline signed short h2n(signed short v)          { return htons(v); }
  79 static inline signed short n2h(signed short v)          { return ntohs(v); }
  80 static inline signed short flip(signed short v)         { return OSSwapInt16(v); }
  81
  82 static inline unsigned char h2n(unsigned char v)        { return v; }
  83 static inline unsigned char n2h(unsigned char v)        { return v; }
  84 static inline unsigned char flip(unsigned char v)       { return v; }
  85 static inline signed char h2n(signed char v)            { return v; }
  86 static inline signed char n2h(signed char v)            { return v; }
  87 static inline signed char flip(signed char v)           { return v; }
  88
  89
  90 //
  91 // Flip pointers
  92 //
  93 template <class Base>
  94 static inline Base *h2n(Base *p)        { return (Base *)h2n(uintptr_t(p)); }
  95
  96 template <class Base>
  97 static inline Base *n2h(Base *p)        { return (Base *)n2h(uintptr_t(p)); }
  98
  99
 100 //
 101 // In-place fix operations
 102 //
 103 template <class Type>
 104 static inline void h2ni(Type &v)        { v = h2n(v); }
 105
 106 template <class Type>
 107 static inline void n2hi(Type &v)        { v = n2h(v); }
 108
 109 //
 110 // Endian<SomeType> keeps NBO values in memory and converts
 111 // during loads and stores. This presumes that you are using
 112 // memory blocks thare are read/written/mapped as amorphous byte
 113 // streams, but want to be byte-order clean using them.
 114 //
 115 // The generic definition uses h2n/n2h to flip bytes. Feel free
 116 // to declare specializations of Endian<T> as appropriate.
 117 //
 118 // Note well that the address of an Endian<T> is not an address-of-T,
 119 // and there is no conversion available.
 120 //
 121 template <class Type>
 122 class Endian {
 123 public:
 124     typedef Type Value;
 125     Endian() : mValue(Type(0)) { }
 126     Endian(Value v) : mValue(h2n(v)) { }
 127
 128     Type get () const                   { return n2h(mValue); }
 129     operator Value () const             { return this->get(); }
 130     Endian &operator = (Value v)        { mValue = h2n(v); return *this; }
 131
 132
 133 private:
 134     Value mValue;
 135 };
 136
 137
 138 }       // end namespace Security
 139
 140
 141 #endif //_H_ENDIAN