| 94ed9b30 |
1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id$ |
| 4 | * |
| 5 | * Remember the longest word seen so far |
| 6 | * |
| 7 | * (c) 2005 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Anag: a simple wordgame helper. |
| 13 | * |
| 14 | * Anag is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * Anag 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 General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with Anag; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Header files ------------------------------------------------------*/ |
| 30 | |
| 31 | #include "anag.h" |
| 32 | |
| 33 | /*----- Data structures ---------------------------------------------------*/ |
| 34 | |
| 35 | typedef struct link { |
| 36 | struct link *next; |
| 37 | char *p; |
| 38 | } link; |
| 39 | |
| 40 | typedef struct node_longest { |
| 41 | node n; |
| 42 | size_t len; |
| 43 | link *l, **lt; |
| 44 | } node_longest; |
| 45 | |
| 46 | /*----- Main code ---------------------------------------------------------*/ |
| 47 | |
| 48 | static void empty(node_longest *n) |
| 49 | { |
| 50 | link *l, *ll; |
| 51 | |
| 52 | for (l = n->l; l; l = ll) { |
| 53 | ll = l->next; |
| 54 | free(l->p); |
| 55 | free(l); |
| 56 | } |
| 57 | n->l = 0; |
| 58 | n->lt = &n->l; |
| 59 | } |
| 60 | |
| 61 | static void insert(node_longest *n, const char *p, size_t sz) |
| 62 | { |
| 63 | link *l; |
| 64 | |
| 65 | n->len = sz; |
| 66 | l = xmalloc(sizeof(*l)); |
| 67 | l->p = xmalloc(sz + 1); |
| 68 | memcpy(l->p, p, sz + 1); |
| 69 | l->next = 0; |
| 70 | *n->lt = l; |
| 71 | n->lt = &l->next; |
| 72 | } |
| 73 | |
| 74 | static int aa_output(void *p) |
| 75 | { |
| 76 | node_longest *n = p; |
| 77 | link *l; |
| 78 | |
| 79 | if (!n->l) return (0); |
| 80 | for (l = n->l; l; l = l->next) |
| 81 | puts(l->p); |
| 82 | return (1); |
| 83 | } |
| 84 | |
| 85 | static int n_longest(node *nn, const char *p, size_t sz) |
| 86 | { |
| 87 | node_longest *n = (node_longest *)nn; |
| 88 | if (sz < n->len) |
| 89 | return (0); |
| 90 | if (sz > n->len) |
| 91 | empty(n); |
| 92 | insert(n, p, sz); |
| 93 | return (0); |
| 94 | } |
| 95 | |
| 96 | static int n_shortest(node *nn, const char *p, size_t sz) |
| 97 | { |
| 98 | node_longest *n = (node_longest *)nn; |
| 99 | if (n->len && sz > n->len) |
| 100 | return (0); |
| 101 | if (!n->len || sz < n->len) |
| 102 | empty(n); |
| 103 | insert(n, p, sz); |
| 104 | return (0); |
| 105 | } |
| 106 | |
| 107 | static node *mklongest(int (*nf)(node *, const char *, size_t), |
| 108 | int (*aa)(void *)) |
| 109 | { |
| 110 | node_longest *n = xmalloc(sizeof(*n)); |
| 111 | n->n.func = nf; |
| 112 | n->len = 0; |
| 113 | n->l = 0; |
| 114 | n->lt = &n->l; |
| 115 | atend_register(aa, n); |
| 116 | return (&n->n); |
| 117 | } |
| 118 | |
| 119 | node *longest(const char *const *av) |
| 120 | { return mklongest(n_longest, aa_output); } |
| 121 | node *shortest(const char *const *av) |
| 122 | { return mklongest(n_shortest, aa_output); } |
| 123 | |
| 124 | /*----- That's all, folks -------------------------------------------------*/ |
~mdw / anag / blame