| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Loading and storing of multiprecision integers |
| 4 | * |
| 5 | * (c) 1999 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | /*----- Header files ------------------------------------------------------*/ |
| 29 | |
| 30 | #include "mp.h" |
| 31 | |
| 32 | /*----- Main code ---------------------------------------------------------*/ |
| 33 | |
| 34 | /* --- @mp_octets@ --- * |
| 35 | * |
| 36 | * Arguments: @const mp *m@ = a multiprecision integer |
| 37 | * |
| 38 | * Returns: The number of octets required to represent @m@. |
| 39 | * |
| 40 | * Use: Calculates the external storage required for a multiprecision |
| 41 | * integer. |
| 42 | */ |
| 43 | |
| 44 | size_t mp_octets(const mp *m) |
| 45 | { |
| 46 | size_t sz; |
| 47 | MPX_OCTETS(sz, m->v, m->vl); |
| 48 | return (sz); |
| 49 | } |
| 50 | |
| 51 | /* --- @mp_octets2c@ --- * |
| 52 | * |
| 53 | * Arguments: @const mp *m@ = a multiprecision integer |
| 54 | * |
| 55 | * Returns: The number of octets required to represent @m@. |
| 56 | * |
| 57 | * Use: Calculates the external storage required for a multiprecision |
| 58 | * integer represented as two's complement. |
| 59 | */ |
| 60 | |
| 61 | size_t mp_octets2c(const mp *m) |
| 62 | { |
| 63 | size_t sz; |
| 64 | MPX_OCTETS2C(sz, m->v, m->vl); |
| 65 | return (sz); |
| 66 | } |
| 67 | |
| 68 | /* --- @mp_bits@ --- * |
| 69 | * |
| 70 | * Arguments: @const mp *m@ = a multiprecision integer |
| 71 | * |
| 72 | * Returns: The number of bits required to represent @m@. |
| 73 | * |
| 74 | * Use: Calculates the external storage required for a multiprecision |
| 75 | * integer. |
| 76 | */ |
| 77 | |
| 78 | unsigned long mp_bits(const mp *m) |
| 79 | { |
| 80 | unsigned long bits; |
| 81 | MPX_BITS(bits, m->v, m->vl); |
| 82 | return (bits); |
| 83 | } |
| 84 | |
| 85 | /* --- @mp_loadl@ --- * |
| 86 | * |
| 87 | * Arguments: @mp *d@ = destination |
| 88 | * @const void *pv@ = pointer to source data |
| 89 | * @size_t sz@ = size of the source data |
| 90 | * |
| 91 | * Returns: Resulting multiprecision number. |
| 92 | * |
| 93 | * Use: Loads a multiprecision number from an array of octets. The |
| 94 | * first byte in the array is the least significant. More |
| 95 | * formally, if the bytes are %$b_0, b_1, \ldots, b_{n-1}$% |
| 96 | * then the result is %$N = \sum_{0 \le i < n} b_i 2^{8i}$%. |
| 97 | */ |
| 98 | |
| 99 | mp *mp_loadl(mp *d, const void *pv, size_t sz) |
| 100 | { |
| 101 | MP_DEST(d, MPW_RQ(sz), MP_UNDEF); |
| 102 | mpx_loadl(d->v, d->vl, pv, sz); |
| 103 | d->f &= ~(MP_UNDEF | MP_NEG); |
| 104 | mp_shrink(d); |
| 105 | return (d); |
| 106 | } |
| 107 | |
| 108 | /* --- @mp_storel@ --- * |
| 109 | * |
| 110 | * Arguments: @const mp *m@ = source |
| 111 | * @void *pv@ = pointer to output array |
| 112 | * @size_t sz@ = size of the output array |
| 113 | * |
| 114 | * Returns: --- |
| 115 | * |
| 116 | * Use: Stores a multiprecision number in an array of octets. The |
| 117 | * first byte in the array is the least significant. If the |
| 118 | * array is too small to represent the number, high-order bits |
| 119 | * are truncated; if the array is too large, high order bytes |
| 120 | * are filled with zeros. More formally, if the number is |
| 121 | * %$N = \sum{0 \le i} b_i 2^{8i}$% where %$0 \le b_i < 256$%, |
| 122 | * then the array is %$b_0, b_1, \ldots, b_{n-1}$%. |
| 123 | */ |
| 124 | |
| 125 | void mp_storel(const mp *m, void *pv, size_t sz) |
| 126 | { |
| 127 | mpx_storel(m->v, m->vl, pv, sz); |
| 128 | } |
| 129 | |
| 130 | /* --- @mp_loadb@ --- * |
| 131 | * |
| 132 | * Arguments: @mp *d@ = destination |
| 133 | * @const void *pv@ = pointer to source data |
| 134 | * @size_t sz@ = size of the source data |
| 135 | * |
| 136 | * Returns: Resulting multiprecision number. |
| 137 | * |
| 138 | * Use: Loads a multiprecision number from an array of octets. The |
| 139 | * last byte in the array is the least significant. More |
| 140 | * formally, if the bytes are %$b_{n-1}, b_{n-2}, \ldots, b_0$% |
| 141 | * then the result is %$N = \sum_{0 \le i < n} b_i 2^{8i}$%. |
| 142 | */ |
| 143 | |
| 144 | mp *mp_loadb(mp *d, const void *pv, size_t sz) |
| 145 | { |
| 146 | MP_DEST(d, MPW_RQ(sz), MP_UNDEF); |
| 147 | mpx_loadb(d->v, d->vl, pv, sz); |
| 148 | d->f &= ~(MP_UNDEF | MP_NEG); |
| 149 | mp_shrink(d); |
| 150 | return (d); |
| 151 | } |
| 152 | |
| 153 | /* --- @mp_storeb@ --- * |
| 154 | * |
| 155 | * Arguments: @const mp *m@ = source |
| 156 | * @void *pv@ = pointer to output array |
| 157 | * @size_t sz@ = size of the output array |
| 158 | * |
| 159 | * Returns: --- |
| 160 | * |
| 161 | * Use: Stores a multiprecision number in an array of octets. The |
| 162 | * last byte in the array is the least significant. If the |
| 163 | * array is too small to represent the number, high-order bits |
| 164 | * are truncated; if the array is too large, high order bytes |
| 165 | * are filled with zeros. More formally, if the number is |
| 166 | * %$N = \sum{0 \le i} b_i 2^{8i}$% where %$0 \le b_i < 256$%, |
| 167 | * then the array is %$b_{n-1}, b_{n-2}, \ldots, b_0$%. |
| 168 | */ |
| 169 | |
| 170 | void mp_storeb(const mp *m, void *pv, size_t sz) |
| 171 | { |
| 172 | mpx_storeb(m->v, m->vl, pv, sz); |
| 173 | } |
| 174 | |
| 175 | /* --- @mp_loadl2c@ --- * |
| 176 | * |
| 177 | * Arguments: @mp *d@ = destination |
| 178 | * @const void *pv@ = pointer to source data |
| 179 | * @size_t sz@ = size of the source data |
| 180 | * |
| 181 | * Returns: Resulting multiprecision number. |
| 182 | * |
| 183 | * Use: Loads a multiprecision number from an array of octets as |
| 184 | * two's complement. The first byte in the array is the least |
| 185 | * significant. |
| 186 | */ |
| 187 | |
| 188 | mp *mp_loadl2c(mp *d, const void *pv, size_t sz) |
| 189 | { |
| 190 | const octet *ov = pv; |
| 191 | MP_DEST(d, MPW_RQ(sz), MP_UNDEF); |
| 192 | if (!sz || !(ov[sz - 1] & 0x80)) { |
| 193 | mpx_loadl(d->v, d->vl, pv, sz); |
| 194 | d->f &= ~MP_NEG; |
| 195 | } else { |
| 196 | mpx_loadl2cn(d->v, d->vl, pv, sz); |
| 197 | d->f |= MP_NEG; |
| 198 | } |
| 199 | d->f &= ~MP_UNDEF; |
| 200 | mp_shrink(d); |
| 201 | return (d); |
| 202 | } |
| 203 | |
| 204 | /* --- @mp_storel2c@ --- * |
| 205 | * |
| 206 | * Arguments: @const mp *m@ = source |
| 207 | * @void *pv@ = pointer to output array |
| 208 | * @size_t sz@ = size of the output array |
| 209 | * |
| 210 | * Returns: --- |
| 211 | * |
| 212 | * Use: Stores a multiprecision number in an array of octets as two's |
| 213 | * complement. The first byte in the array is the least |
| 214 | * significant. If the array is too small to represent the |
| 215 | * number, high-order bits are truncated; if the array is too |
| 216 | * large, high order bytes are sign-extended. |
| 217 | */ |
| 218 | |
| 219 | void mp_storel2c(const mp *m, void *pv, size_t sz) |
| 220 | { |
| 221 | if (MP_NEGP(m)) |
| 222 | mpx_storel2cn(m->v, m->vl, pv, sz); |
| 223 | else |
| 224 | mpx_storel(m->v, m->vl, pv, sz); |
| 225 | } |
| 226 | |
| 227 | /* --- @mp_loadb2c@ --- * |
| 228 | * |
| 229 | * Arguments: @mp *d@ = destination |
| 230 | * @const void *pv@ = pointer to source data |
| 231 | * @size_t sz@ = size of the source data |
| 232 | * |
| 233 | * Returns: Resulting multiprecision number. |
| 234 | * |
| 235 | * Use: Loads a multiprecision number from an array of octets as |
| 236 | * two's complement. The last byte in the array is the least |
| 237 | * significant. |
| 238 | */ |
| 239 | |
| 240 | mp *mp_loadb2c(mp *d, const void *pv, size_t sz) |
| 241 | { |
| 242 | const octet *ov = pv; |
| 243 | MP_DEST(d, MPW_RQ(sz), MP_UNDEF); |
| 244 | if (!sz || !(ov[0] & 0x80)) { |
| 245 | mpx_loadb(d->v, d->vl, pv, sz); |
| 246 | d->f &= ~MP_NEG; |
| 247 | } else { |
| 248 | mpx_loadb2cn(d->v, d->vl, pv, sz); |
| 249 | d->f |= MP_NEG; |
| 250 | } |
| 251 | d->f &= ~MP_UNDEF; |
| 252 | mp_shrink(d); |
| 253 | return (d); |
| 254 | } |
| 255 | |
| 256 | /* --- @mp_storeb2c@ --- * |
| 257 | * |
| 258 | * Arguments: @const mp *m@ = source |
| 259 | * @void *pv@ = pointer to output array |
| 260 | * @size_t sz@ = size of the output array |
| 261 | * |
| 262 | * Returns: --- |
| 263 | * |
| 264 | * Use: Stores a multiprecision number in an array of octets, as |
| 265 | * two's complement. The last byte in the array is the least |
| 266 | * significant. If the array is too small to represent the |
| 267 | * number, high-order bits are truncated; if the array is too |
| 268 | * large, high order bytes are sign-extended. |
| 269 | */ |
| 270 | |
| 271 | void mp_storeb2c(const mp *m, void *pv, size_t sz) |
| 272 | { |
| 273 | if (MP_NEGP(m)) |
| 274 | mpx_storeb2cn(m->v, m->vl, pv, sz); |
| 275 | else |
| 276 | mpx_storeb(m->v, m->vl, pv, sz); |
| 277 | } |
| 278 | |
| 279 | /*----- That's all, folks -------------------------------------------------*/ |