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