| | 1 | /* bmpbit.c |
| | 2 | * Greg Cook, 24/Feb/2016 |
| | 3 | */ |
| | 4 | |
| | 5 | /* CRC RevEng, an arbitrary-precision CRC calculator and algorithm finder |
| | 6 | * Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015, 2016 Gregory Cook |
| | 7 | * |
| | 8 | * This file is part of CRC RevEng. |
| | 9 | * |
| | 10 | * CRC RevEng is free software: you can redistribute it and/or modify |
| | 11 | * it under the terms of the GNU General Public License as published by |
| | 12 | * the Free Software Foundation, either version 3 of the License, or |
| | 13 | * (at your option) any later version. |
| | 14 | * |
| | 15 | * CRC RevEng is distributed in the hope that it will be useful, |
| | 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| | 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| | 18 | * GNU General Public License for more details. |
| | 19 | * |
| | 20 | * You should have received a copy of the GNU General Public License |
| | 21 | * along with CRC RevEng. If not, see <http://www.gnu.org/licenses/>. |
| | 22 | */ |
| | 23 | |
| | 24 | #ifdef BMPTST |
| | 25 | # include <stdio.h> |
| | 26 | # include <stdlib.h> |
| | 27 | #else |
| | 28 | # define FILE void |
| | 29 | #endif |
| | 30 | #include "reveng.h" |
| | 31 | |
| | 32 | #if (defined BMPTST) || (BMP_BIT < 32) |
| | 33 | /* Size in bits of a bmp_t. Not necessarily a power of two. */ |
| | 34 | int bmpbit; |
| | 35 | |
| | 36 | /* The highest power of two that is strictly less than BMP_BIT. |
| | 37 | * Initialises the index of a binary search for set bits in a bmp_t. |
| | 38 | * (Computed correctly for BMP_BIT >= 2) |
| | 39 | */ |
| | 40 | int bmpsub; |
| | 41 | |
| | 42 | void |
| | 43 | setbmp(void) { |
| | 44 | /* Initialise BMP_BIT and BMP_SUB for the local architecture. */ |
| | 45 | bmp_t bmpmax = ~(bmp_t) 0; |
| | 46 | |
| | 47 | bmpbit = 0; bmpsub = 1; |
| | 48 | |
| | 49 | while(bmpmax) { |
| | 50 | bmpmax <<= 1; |
| | 51 | ++bmpbit; |
| | 52 | } |
| | 53 | |
| | 54 | while((bmpsub | (bmpsub - 1)) < bmpbit - 1) |
| | 55 | bmpsub <<= 1; |
| | 56 | } |
| | 57 | #endif |
| | 58 | |
| | 59 | #ifdef BMPTST |
| | 60 | int |
| | 61 | main(int argc, char *argv[]) { |
| | 62 | /* check the compile-time bitmap width is correct, otherwise |
| | 63 | * searches run forever. */ |
| | 64 | # if BMP_BIT > 0 |
| | 65 | setbmp(); |
| | 66 | if(BMP_BIT != bmpbit || BMP_SUB != bmpsub) { |
| | 67 | fprintf(stderr,"reveng: configuration fault. Update " |
| | 68 | "config.h with these definitions and " |
| | 69 | "recompile:\n" |
| | 70 | "\t#define BMP_BIT %d\n" |
| | 71 | "\t#define BMP_SUB %d\n", |
| | 72 | bmpbit, bmpsub); |
| | 73 | exit(EXIT_FAILURE); |
| | 74 | } |
| | 75 | # endif /* BMP_BIT > 0 */ |
| | 76 | /* check the bitmap constant macro */ |
| | 77 | if(~(bmp_t) 0 != ~BMP_C(0)) { |
| | 78 | fprintf(stderr, "reveng: configuration fault. Edit " |
| | 79 | "the definition of BMP_C() in config.h to " |
| | 80 | "match BMP_T and recompile.\n"); |
| | 81 | exit(EXIT_FAILURE); |
| | 82 | } |
| | 83 | exit(EXIT_SUCCESS); |
| | 84 | } |
| | 85 | |
| | 86 | #endif /* BMPTST */ |
projects / proxmark3-svn / blame_incremental