parse.c revision 1.12 
1/*	$NetBSD: parse.c,v 1.12 2001/06/19 13:42:09 wiz Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38#if 0
39static char sccsid[] = "@(#)parse.c	8.2 (Berkeley) 4/28/95";
40#else
41__RCSID("$NetBSD: parse.c,v 1.12 2001/06/19 13:42:09 wiz Exp $");
42#endif
43#endif				/* not lint */
44
45#include "extern.h"
46
47#define HASHSIZE	256
48#define HASHMUL		81
49#define HASHMASK	(HASHSIZE - 1)
50
51static int hash __P((const char *));
52static void install __P((struct wlist *));
53static struct wlist *lookup __P((const char *));
54
55static struct wlist *hashtab[HASHSIZE];
56
57void
58wordinit()
59{
60	struct wlist *w;
61
62	for (w = wlist; w->string; w++)
63		install(w);
64}
65
66static int
67hash(s)
68	const char   *s;
69{
70	int     hashval = 0;
71
72	while (*s) {
73		hashval += *s++;
74		hashval *= HASHMUL;
75		hashval &= HASHMASK;
76	}
77	return hashval;
78}
79
80static struct wlist *
81lookup(s)
82	const char   *s;
83{
84	struct wlist *wp;
85
86	for (wp = hashtab[hash(s)]; wp != NULL; wp = wp->next)
87		if (*s == *wp->string && strcmp(s, wp->string) == 0)
88			return wp;
89	return NULL;
90}
91
92static void
93install(wp)
94	struct wlist *wp;
95{
96	int     hashval;
97
98	if (lookup(wp->string) == NULL) {
99		hashval = hash(wp->string);
100		wp->next = hashtab[hashval];
101		hashtab[hashval] = wp;
102	} else
103		printf("Multiply defined %s.\n", wp->string);
104}
105
106void
107parse()
108{
109	struct wlist *wp;
110	int     n;
111	int     flag;
112
113	wordnumber = 0;		/* for cypher */
114	for (n = 0; n <= wordcount; n++) {
115		if ((wp = lookup(words[n])) == NULL) {
116			wordvalue[n] = -1;
117			wordtype[n] = -1;
118		} else {
119			wordvalue[n] = wp->value;
120			wordtype[n] = wp->article;
121		}
122	}
123	/* We never use adjectives for anything, so yank them all. */
124	for (n = 1; n < wordcount; n++)
125		if (wordtype[n] == ADJS) {
126			int i;
127			for (i = n + 1; i < wordcount; i++) {
128				wordtype[i - 1] = wordtype[i];
129				wordvalue[i - 1] = wordvalue[i];
130				strcpy(words[i - 1], words[i]);
131			}
132			wordcount--;
133		}
134	/* Don't let a comma mean AND if followed by a verb. */
135	for (n = 0; n < wordcount; n++)
136		if (wordvalue[n] == AND && words[n][0] == ','
137		    && wordtype[n + 1] == VERB) {
138			wordvalue[n] = -1;
139			wordtype[n] = -1;
140		}
141	/* Trim "AND AND" which can happen naturally at the end of a
142	 * comma-delimited list.
143	 */
144	for (n = 1; n < wordcount; n++)
145		if (wordvalue[n - 1] == AND && wordvalue[n] == AND) {
146			int i;
147			for (i = n + 1; i < wordcount; i++) {
148				wordtype[i - 1] = wordtype[i];
149				wordvalue[i - 1] = wordvalue[i];
150				strcpy(words[i - 1], words[i]);
151			}
152			wordcount--;
153		}
154
155	/* If there is a sequence (NOUN | OBJECT) AND EVERYTHING
156	 * then move all the EVERYTHINGs to the beginning, since that's where
157	 * they're expected.  We can't get rid of the NOUNs and OBJECTs in
158	 * case they aren't in EVERYTHING (i.e. not here or nonexistent).
159	 */
160	flag = 1;
161	while (flag) {
162		flag = 0;
163		for (n = 1; n < wordcount; n++)
164			if ((wordtype[n - 1] == NOUNS || wordtype[n - 1] == OBJECT) &&
165			    wordvalue[n] == AND && wordvalue[n + 1] == EVERYTHING) {
166				char tmpword[WORDLEN];
167				wordvalue[n + 1] = wordvalue[n - 1];
168				wordvalue[n - 1] = EVERYTHING;
169				wordtype[n + 1] = wordtype[n - 1];
170				wordtype[n - 1] = OBJECT;
171				strcpy(tmpword, words[n - 1]);
172				strcpy(words[n - 1], words[n + 1]);
173				strcpy(words[n + 1], tmpword);
174				flag = 1;
175		}
176		/* And trim EVERYTHING AND EVERYTHING. */
177		for (n = 1; n < wordcount; n++)
178			if (wordvalue[n - 1] == EVERYTHING &&
179			    wordvalue[n] == AND && wordvalue[n + 1] == EVERYTHING) {
180				int i;
181				for (i = n + 1; i < wordcount; i++) {
182					wordtype[i - 1] = wordtype[i + 1];
183					wordvalue[i - 1] = wordvalue[i + 1];
184					strcpy(words[i - 1], words[i + 1]);
185				}
186				wordcount--;
187				wordcount--;
188				flag = 1;
189			}
190	}
191}
192