| 1 | /* |
| 2 | * Glide64 - Glide video plugin for Nintendo 64 emulators. |
| 3 | * Copyright (c) 2002 Dave2001 |
| 4 | * Copyright (c) 2003-2009 Sergey 'Gonetz' Lipski |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | |
| 21 | //**************************************************************** |
| 22 | // |
| 23 | // Glide64 - Glide Plugin for Nintendo 64 emulators |
| 24 | // Project started on December 29th, 2001 |
| 25 | // |
| 26 | // Authors: |
| 27 | // Dave2001, original author, founded the project in 2001, left it in 2002 |
| 28 | // Gugaman, joined the project in 2002, left it in 2002 |
| 29 | // Sergey 'Gonetz' Lipski, joined the project in 2002, main author since fall of 2002 |
| 30 | // Hiroshi 'KoolSmoky' Morii, joined the project in 2007 |
| 31 | // |
| 32 | //**************************************************************** |
| 33 | // |
| 34 | // To modify Glide64: |
| 35 | // * Write your name and (optional)email, commented by your work, so I know who did it, and so that you can find which parts you modified when it comes time to send it to me. |
| 36 | // * Do NOT send me the whole project or file that you modified. Take out your modified code sections, and tell me where to put them. If people sent the whole thing, I would have many different versions, but no idea how to combine them all. |
| 37 | // |
| 38 | //**************************************************************** |
| 39 | // |
| 40 | // CRC32 calculation functions |
| 41 | // |
| 42 | // Created by Gonetz, 2004 |
| 43 | // |
| 44 | //**************************************************************** |
| 45 | //* |
| 46 | |
| 47 | #define CRC32_POLYNOMIAL 0x04C11DB7 |
| 48 | |
| 49 | unsigned int CRCTable[ 256 ]; |
| 50 | |
| 51 | unsigned int Reflect( unsigned int ref, char ch ) |
| 52 | { |
| 53 | unsigned int value = 0; |
| 54 | |
| 55 | // Swap bit 0 for bit 7 |
| 56 | // bit 1 for bit 6, etc. |
| 57 | for (char i = 1; i < (ch + 1); i++) |
| 58 | { |
| 59 | if(ref & 1) |
| 60 | value |= 1 << (ch - i); |
| 61 | ref >>= 1; |
| 62 | } |
| 63 | return value; |
| 64 | } |
| 65 | |
| 66 | void CRC_BuildTable() |
| 67 | { |
| 68 | unsigned int crc; |
| 69 | |
| 70 | for (unsigned i = 0; i <= 255; i++) |
| 71 | { |
| 72 | crc = Reflect( i, 8 ) << 24; |
| 73 | for (unsigned j = 0; j < 8; j++) |
| 74 | crc = (crc << 1) ^ (crc & (1 << 31) ? CRC32_POLYNOMIAL : 0); |
| 75 | |
| 76 | CRCTable[i] = Reflect( crc, 32 ); |
| 77 | } |
| 78 | } |
| 79 | //*/ |
| 80 | //* |
| 81 | unsigned int CRC32( unsigned int crc, void *buffer, unsigned int count ) |
| 82 | { |
| 83 | unsigned int orig = crc; |
| 84 | unsigned char * p = reinterpret_cast<unsigned char*>(buffer); |
| 85 | while (count--) |
| 86 | crc = (crc >> 8) ^ CRCTable[(crc & 0xFF) ^ *p++]; |
| 87 | return crc ^ orig; |
| 88 | } |
| 89 | //*/ |
| 90 | |
| 91 | /* |
| 92 | wxUint32 CRC_Calculate( wxUint32 crc, void *buffer, wxUint32 count ) |
| 93 | { |
| 94 | wxUint32 Crc32=crc; |
| 95 | __asm { |
| 96 | mov esi, buffer |
| 97 | mov ecx, count |
| 98 | mov edx, crc |
| 99 | xor eax, eax |
| 100 | |
| 101 | loop1: |
| 102 | inc esi |
| 103 | mov al, dl |
| 104 | xor al, byte ptr [esi] |
| 105 | shr edx, 8 |
| 106 | mov ebx, [CRCTable+eax*4] |
| 107 | xor edx, ebx |
| 108 | |
| 109 | loop loop1 |
| 110 | |
| 111 | xor Crc32, edx |
| 112 | } |
| 113 | return Crc32; |
| 114 | } |
| 115 | */ |
| 116 | |
| 117 | /* |
| 118 | unsigned int CRC_Calculate( unsigned int crc, void *buffer, unsigned int count ) |
| 119 | { |
| 120 | unsigned int Crc32=crc; |
| 121 | __asm { |
| 122 | mov esi, buffer |
| 123 | mov edx, count |
| 124 | add edx, esi |
| 125 | mov ecx, crc |
| 126 | |
| 127 | loop1: |
| 128 | mov bl, byte ptr [esi] |
| 129 | movzx eax, cl |
| 130 | inc esi |
| 131 | xor al, bl |
| 132 | shr ecx, 8 |
| 133 | mov ebx, [CRCTable+eax*4] |
| 134 | xor ecx, ebx |
| 135 | |
| 136 | cmp edx, esi |
| 137 | jne loop1 |
| 138 | |
| 139 | xor Crc32, ecx |
| 140 | } |
| 141 | return Crc32; |
| 142 | } |
| 143 | //*/ |
| 144 | |