| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: mp-misc.c,v 1.3 2000/07/29 17:03:31 mdw Exp $ |
| 4 | * |
| 5 | * Miscellaneous multiprecision support functions |
| 6 | * |
| 7 | * (c) 1999 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Catacomb. |
| 13 | * |
| 14 | * Catacomb is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU Library General Public License as |
| 16 | * published by the Free Software Foundation; either version 2 of the |
| 17 | * License, or (at your option) any later version. |
| 18 | * |
| 19 | * Catacomb is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU Library General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU Library General Public |
| 25 | * License along with Catacomb; if not, write to the Free |
| 26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Revision history --------------------------------------------------* |
| 31 | * |
| 32 | * $Log: mp-misc.c,v $ |
| 33 | * Revision 1.3 2000/07/29 17:03:31 mdw |
| 34 | * Add support for left-to-right bitscanning, for use in modular |
| 35 | * exponentiation. |
| 36 | * |
| 37 | * Revision 1.2 2000/06/17 11:45:09 mdw |
| 38 | * Major memory management overhaul. Added arena support. Use the secure |
| 39 | * arena for secret integers. Replace and improve the MP management macros |
| 40 | * (e.g., replace MP_MODIFY by MP_DEST). |
| 41 | * |
| 42 | * Revision 1.1 1999/11/17 18:02:16 mdw |
| 43 | * New multiprecision integer arithmetic suite. |
| 44 | * |
| 45 | */ |
| 46 | |
| 47 | /*----- Header files ------------------------------------------------------*/ |
| 48 | |
| 49 | #include "mp.h" |
| 50 | |
| 51 | /*----- Basic manipulation ------------------------------------------------*/ |
| 52 | |
| 53 | /* --- @mp_shrink@ --- * |
| 54 | * |
| 55 | * Arguments: @mp *m@ = pointer to a multiprecision integer |
| 56 | * |
| 57 | * Returns: --- |
| 58 | * |
| 59 | * Use: Reduces the recorded length of an integer. This doesn't |
| 60 | * reduce the amount of memory used, although it can improve |
| 61 | * performance a bit. To reduce memory, use @mp_minimize@ |
| 62 | * instead. This can't change the value of an integer, and is |
| 63 | * therefore safe to use even when there are multiple |
| 64 | * references. |
| 65 | */ |
| 66 | |
| 67 | void mp_shrink(mp *m) { MP_SHRINK(m); } |
| 68 | |
| 69 | /* --- @mp_minimize@ --- * |
| 70 | * |
| 71 | * Arguments: @mp *m@ = pointer to a multiprecision integer |
| 72 | * |
| 73 | * Returns: --- |
| 74 | * |
| 75 | * Use: Reduces the amount of memory an integer uses. It's best to |
| 76 | * do this to numbers which aren't going to change in the |
| 77 | * future. |
| 78 | */ |
| 79 | |
| 80 | void mp_minimize(mp *m) |
| 81 | { |
| 82 | MP_SHRINK(m); |
| 83 | MP_RESIZE(m, MP_LEN(m)); |
| 84 | } |
| 85 | |
| 86 | /*----- Bit scanning ------------------------------------------------------*/ |
| 87 | |
| 88 | /* --- @mp_scan@ --- * |
| 89 | * |
| 90 | * Arguments: @mpscan *sc@ = pointer to bitscanner block |
| 91 | * @const mp *m@ = pointer to a multiprecision integer |
| 92 | * |
| 93 | * Returns: --- |
| 94 | * |
| 95 | * Use: Initializes a bitscanner on a multiprecision integer. |
| 96 | */ |
| 97 | |
| 98 | void mp_scan(mpscan *sc, const mp *m) { MP_SCAN(sc, m); } |
| 99 | |
| 100 | /* --- @mp_scan@ --- * |
| 101 | * |
| 102 | * Arguments: @mpscan *sc@ = pointer to bitscanner block |
| 103 | * @const mp *m@ = pointer to a multiprecision integer |
| 104 | * |
| 105 | * Returns: --- |
| 106 | * |
| 107 | * Use: Initializes a reverse bitscanner on a multiprecision |
| 108 | * integer. |
| 109 | */ |
| 110 | |
| 111 | void mp_rscan(mpscan *sc, const mp *m) { MP_RSCAN(sc, m); } |
| 112 | |
| 113 | /*----- That's all, folks -------------------------------------------------*/ |