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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 -------------------------------------------------*/ |