| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: mp-io.c,v 1.3 1999/11/21 22:13:02 mdw Exp $ |
| 4 | * |
| 5 | * Loading and storing of multiprecision integers |
| 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-io.c,v $ |
| 33 | * Revision 1.3 1999/11/21 22:13:02 mdw |
| 34 | * Add mp version of MPX_BITS. |
| 35 | * |
| 36 | * Revision 1.2 1999/11/19 13:19:06 mdw |
| 37 | * Set flags on results correctly. |
| 38 | * |
| 39 | * Revision 1.1 1999/11/17 18:02:16 mdw |
| 40 | * New multiprecision integer arithmetic suite. |
| 41 | * |
| 42 | */ |
| 43 | |
| 44 | /*----- Header files ------------------------------------------------------*/ |
| 45 | |
| 46 | #include "mp.h" |
| 47 | |
| 48 | /*----- Main code ---------------------------------------------------------*/ |
| 49 | |
| 50 | /* --- @mp_octets@ --- * |
| 51 | * |
| 52 | * Arguments: @const mp *m@ = a multiprecision integer |
| 53 | * |
| 54 | * Returns: The number of octets required to represent @m@. |
| 55 | * |
| 56 | * Use: Calculates the external storage required for a multiprecision |
| 57 | * integer. |
| 58 | */ |
| 59 | |
| 60 | size_t mp_octets(const mp *m) |
| 61 | { |
| 62 | size_t sz; |
| 63 | MPX_OCTETS(sz, m->v, m->vl); |
| 64 | return (sz); |
| 65 | } |
| 66 | |
| 67 | /* --- @mp_bits@ --- * |
| 68 | * |
| 69 | * Arguments: @const mp *m@ = a multiprecision integer |
| 70 | * |
| 71 | * Returns: The number of bits required to represent @m@. |
| 72 | * |
| 73 | * Use: Calculates the external storage required for a multiprecision |
| 74 | * integer. |
| 75 | */ |
| 76 | |
| 77 | unsigned long mp_bits(const mp *m) |
| 78 | { |
| 79 | unsigned long bits; |
| 80 | MPX_BITS(bits, m->v, m->vl); |
| 81 | return (bits); |
| 82 | } |
| 83 | |
| 84 | /* --- @mp_loadl@ --- * |
| 85 | * |
| 86 | * Arguments: @mp *d@ = destination |
| 87 | * @const void *pv@ = pointer to source data |
| 88 | * @size_t sz@ = size of the source data |
| 89 | * |
| 90 | * Returns: Resulting multiprecision number. |
| 91 | * |
| 92 | * Use: Loads a multiprecision number from an array of octets. The |
| 93 | * first byte in the array is the least significant. More |
| 94 | * formally, if the bytes are %$b_0, b_1, \ldots, b_{n-1}$% |
| 95 | * then the result is %$N = \sum_{0 \le i < n} b_i 2^{8i}$%. |
| 96 | */ |
| 97 | |
| 98 | mp *mp_loadl(mp *d, const void *pv, size_t sz) |
| 99 | { |
| 100 | MP_MODIFY(d, MPW_RQ(sz)); |
| 101 | mpx_loadl(d->v, d->vl, pv, sz); |
| 102 | d->f &= ~(MP_UNDEF | MP_NEG); |
| 103 | mp_shrink(d); |
| 104 | return (d); |
| 105 | } |
| 106 | |
| 107 | /* --- @mp_storel@ --- * |
| 108 | * |
| 109 | * Arguments: @const mp *m@ = source |
| 110 | * @void *pv@ = pointer to output array |
| 111 | * @size_t sz@ = size of the output array |
| 112 | * |
| 113 | * Returns: --- |
| 114 | * |
| 115 | * Use: Stores a multiprecision number in an array of octets. The |
| 116 | * first byte in the array is the least significant. If the |
| 117 | * array is too small to represent the number, high-order bits |
| 118 | * are truncated; if the array is too large, high order bytes |
| 119 | * are filled with zeros. More formally, if the number is |
| 120 | * %$N = \sum{0 \le i} b_i 2^{8i}$% where %$0 \le b_i < 256$%, |
| 121 | * then the array is %$b_0, b_1, \ldots, b_{n-1}$%. |
| 122 | */ |
| 123 | |
| 124 | void mp_storel(const mp *m, void *pv, size_t sz) |
| 125 | { |
| 126 | mpx_storel(m->v, m->vl, pv, sz); |
| 127 | } |
| 128 | |
| 129 | /* --- @mp_loadb@ --- * |
| 130 | * |
| 131 | * Arguments: @mp *d@ = destination |
| 132 | * @const void *pv@ = pointer to source data |
| 133 | * @size_t sz@ = size of the source data |
| 134 | * |
| 135 | * Returns: Resulting multiprecision number. |
| 136 | * |
| 137 | * Use: Loads a multiprecision number from an array of octets. The |
| 138 | * last byte in the array is the least significant. More |
| 139 | * formally, if the bytes are %$b_{n-1}, b_{n-2}, \ldots, b_0$% |
| 140 | * then the result is %$N = \sum_{0 \le i < n} b_i 2^{8i}$%. |
| 141 | */ |
| 142 | |
| 143 | mp *mp_loadb(mp *d, const void *pv, size_t sz) |
| 144 | { |
| 145 | MP_MODIFY(d, MPW_RQ(sz)); |
| 146 | mpx_loadb(d->v, d->vl, pv, sz); |
| 147 | d->f &= ~(MP_UNDEF | MP_NEG); |
| 148 | mp_shrink(d); |
| 149 | return (d); |
| 150 | } |
| 151 | |
| 152 | /* --- @mp_storeb@ --- * |
| 153 | * |
| 154 | * Arguments: @const mp *m@ = source |
| 155 | * @void *pv@ = pointer to output array |
| 156 | * @size_t sz@ = size of the output array |
| 157 | * |
| 158 | * Returns: --- |
| 159 | * |
| 160 | * Use: Stores a multiprecision number in an array of octets. The |
| 161 | * last byte in the array is the least significant. If the |
| 162 | * array is too small to represent the number, high-order bits |
| 163 | * are truncated; if the array is too large, high order bytes |
| 164 | * are filled with zeros. More formally, if the number is |
| 165 | * %$N = \sum{0 \le i} b_i 2^{8i}$% where %$0 \le b_i < 256$%, |
| 166 | * then the array is %$b_{n-1}, b_{n-2}, \ldots, b_0$%. |
| 167 | */ |
| 168 | |
| 169 | void mp_storeb(const mp *m, void *pv, size_t sz) |
| 170 | { |
| 171 | mpx_storeb(m->v, m->vl, pv, sz); |
| 172 | } |
| 173 | |
| 174 | /*----- That's all, folks -------------------------------------------------*/ |