| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Reading and writing large integers on strings |
| 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 <string.h> |
| 31 | |
| 32 | #include "mptext.h" |
| 33 | |
| 34 | /*----- Main code ---------------------------------------------------------*/ |
| 35 | |
| 36 | /* --- Operations table --- */ |
| 37 | |
| 38 | static int get(void *p) |
| 39 | { |
| 40 | mptext_stringctx *c = p; |
| 41 | if (c->buf >= c->lim) |
| 42 | return (EOF); |
| 43 | return ((unsigned char)*c->buf++); |
| 44 | } |
| 45 | |
| 46 | static void unget(int ch, void *p) |
| 47 | { |
| 48 | mptext_stringctx *c = p; |
| 49 | if (ch != EOF) |
| 50 | c->buf--; |
| 51 | } |
| 52 | |
| 53 | static int put(const char *s, size_t sz, void *p) |
| 54 | { |
| 55 | mptext_stringctx *c = p; |
| 56 | int rc = 0; |
| 57 | if (sz > c->lim - c->buf) { |
| 58 | sz = c->lim - c->buf; |
| 59 | rc = EOF; |
| 60 | } |
| 61 | if (sz) { |
| 62 | memcpy(c->buf, s, sz); |
| 63 | c->buf += sz; |
| 64 | } |
| 65 | return (rc); |
| 66 | } |
| 67 | |
| 68 | const mptext_ops mptext_stringops = { get, unget, put }; |
| 69 | |
| 70 | /* --- Convenience functions --- */ |
| 71 | |
| 72 | mp *mp_readstring(mp *m, const char *p, char **end, int radix) |
| 73 | { |
| 74 | mptext_stringctx c; |
| 75 | c.buf = (/*unconst */ char *)p; |
| 76 | c.lim = c.buf + strlen(p); |
| 77 | m = mp_read(m, radix, &mptext_stringops, &c); |
| 78 | if (end) |
| 79 | *end = c.buf; |
| 80 | return (m); |
| 81 | } |
| 82 | |
| 83 | int mp_writestring(mp *m, char *p, size_t sz, int radix) |
| 84 | { |
| 85 | mptext_stringctx c; |
| 86 | int rc; |
| 87 | if (!sz) |
| 88 | return (0); |
| 89 | c.buf = p; |
| 90 | c.lim = p + sz - 1; |
| 91 | rc = mp_write(m, radix, &mptext_stringops, &c); |
| 92 | *c.buf = 0; |
| 93 | return (rc); |
| 94 | } |
| 95 | |
| 96 | /*----- That's all, folks -------------------------------------------------*/ |