00001 /******************************************************************************* 00002 00003 @file ByteSwap.d 00004 00005 Copyright (c) 2004 Kris Bell 00006 00007 This software is provided 'as-is', without any express or implied 00008 warranty. In no event will the authors be held liable for damages 00009 of any kind arising from the use of this software. 00010 00011 Permission is hereby granted to anyone to use this software for any 00012 purpose, including commercial applications, and to alter it and/or 00013 redistribute it freely, subject to the following restrictions: 00014 00015 1. The origin of this software must not be misrepresented; you must 00016 not claim that you wrote the original software. If you use this 00017 software in a product, an acknowledgment within documentation of 00018 said product would be appreciated but is not required. 00019 00020 2. Altered source versions must be plainly marked as such, and must 00021 not be misrepresented as being the original software. 00022 00023 3. This notice may not be removed or altered from any distribution 00024 of the source. 00025 00026 4. Derivative works are permitted, but they must carry this notice 00027 in full and credit the original source. 00028 00029 00030 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 00031 00032 00033 @version Initial version; October 2004 00034 00035 Feb 20th 2005 - Asm version thrown away by Aleksey Bobnev :)) 00036 non-asm version now makes use of bswap intrinsic 00037 00038 @author Kris 00039 Aleksey Bobnev 00040 00041 *******************************************************************************/ 00042 00043 module mango.sys.ByteSwap; 00044 00045 import std.intrinsic; 00046 00047 /******************************************************************************* 00048 00049 Reverse byte order for specific datum sizes. Note that the 00050 byte-swap approach avoids alignment issues, so is probably 00051 faster overall than a traditional 'shift' implementation. 00052 00053 *******************************************************************************/ 00054 00055 struct ByteSwap 00056 { 00057 /*********************************************************************** 00058 00059 ***********************************************************************/ 00060 00061 final static void swap16 (void *dst, uint count) 00062 { 00063 ubyte* p = cast(ubyte*) dst; 00064 while (count) 00065 { 00066 ubyte b = p[0]; 00067 p[0] = p[1]; 00068 p[1] = b; 00069 00070 p += short.sizeof; 00071 count -= short.sizeof; 00072 } 00073 } 00074 00075 /*********************************************************************** 00076 00077 ***********************************************************************/ 00078 00079 final static void swap32 (void *dst, uint count) 00080 { 00081 uint* p = cast(uint*) dst; 00082 while (count) 00083 { 00084 *p = bswap(*p); 00085 p ++; 00086 count -= int.sizeof; 00087 } 00088 } 00089 00090 /*********************************************************************** 00091 00092 ***********************************************************************/ 00093 00094 final static void swap64 (void *dst, uint count) 00095 { 00096 uint* p = cast(uint*) dst; 00097 while (count) 00098 { 00099 uint i = p[0]; 00100 p[0] = bswap(p[1]); 00101 p[1] = bswap(i); 00102 00103 p += (long.sizeof / int.sizeof); 00104 count -= long.sizeof; 00105 } 00106 } 00107 00108 /*********************************************************************** 00109 00110 ***********************************************************************/ 00111 00112 final static void swap80 (void *dst, uint count) 00113 { 00114 ubyte* p = cast(ubyte*) dst; 00115 while (count) 00116 { 00117 ubyte b = p[0]; 00118 p[0] = p[9]; 00119 p[9] = b; 00120 00121 b = p[1]; 00122 p[1] = p[8]; 00123 p[8] = b; 00124 00125 b = p[2]; 00126 p[2] = p[7]; 00127 p[7] = b; 00128 00129 b = p[3]; 00130 p[3] = p[6]; 00131 p[6] = b; 00132 00133 b = p[4]; 00134 p[4] = p[5]; 00135 p[5] = b; 00136 00137 p += real.sizeof; 00138 count -= real.sizeof; 00139 } 00140 } 00141 }