grammar.c revision c64d04dedd1800cfc02a72e0109f0b806f644535 
1/***********************************************************
2Copyright 1991 by Stichting Mathematisch Centrum, Amsterdam, The
3Netherlands.
4
5                        All Rights Reserved
6
7Permission to use, copy, modify, and distribute this software and its
8documentation for any purpose and without fee is hereby granted,
9provided that the above copyright notice appear in all copies and that
10both that copyright notice and this permission notice appear in
11supporting documentation, and that the names of Stichting Mathematisch
12Centrum or CWI not be used in advertising or publicity pertaining to
13distribution of the software without specific, written prior permission.
14
15STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
16THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
17FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
18FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
21OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22
23******************************************************************/
24
25/* Grammar implementation */
26
27#include "pgenheaders.h"
28
29#include <ctype.h>
30
31#include "assert.h"
32#include "token.h"
33#include "grammar.h"
34
35extern int debugging;
36
37grammar *
38newgrammar(start)
39	int start;
40{
41	grammar *g;
42
43	g = NEW(grammar, 1);
44	if (g == NULL)
45		fatal("no mem for new grammar");
46	g->g_ndfas = 0;
47	g->g_dfa = NULL;
48	g->g_start = start;
49	g->g_ll.ll_nlabels = 0;
50	g->g_ll.ll_label = NULL;
51	return g;
52}
53
54dfa *
55adddfa(g, type, name)
56	grammar *g;
57	int type;
58	char *name;
59{
60	dfa *d;
61
62	RESIZE(g->g_dfa, dfa, g->g_ndfas + 1);
63	if (g->g_dfa == NULL)
64		fatal("no mem to resize dfa in adddfa");
65	d = &g->g_dfa[g->g_ndfas++];
66	d->d_type = type;
67	d->d_name = name;
68	d->d_nstates = 0;
69	d->d_state = NULL;
70	d->d_initial = -1;
71	d->d_first = NULL;
72	return d; /* Only use while fresh! */
73}
74
75int
76addstate(d)
77	dfa *d;
78{
79	state *s;
80
81	RESIZE(d->d_state, state, d->d_nstates + 1);
82	if (d->d_state == NULL)
83		fatal("no mem to resize state in addstate");
84	s = &d->d_state[d->d_nstates++];
85	s->s_narcs = 0;
86	s->s_arc = NULL;
87	return s - d->d_state;
88}
89
90void
91addarc(d, from, to, lbl)
92	dfa *d;
93	int lbl;
94{
95	state *s;
96	arc *a;
97
98	assert(0 <= from && from < d->d_nstates);
99	assert(0 <= to && to < d->d_nstates);
100
101	s = &d->d_state[from];
102	RESIZE(s->s_arc, arc, s->s_narcs + 1);
103	if (s->s_arc == NULL)
104		fatal("no mem to resize arc list in addarc");
105	a = &s->s_arc[s->s_narcs++];
106	a->a_lbl = lbl;
107	a->a_arrow = to;
108}
109
110int
111addlabel(ll, type, str)
112	labellist *ll;
113	int type;
114	char *str;
115{
116	int i;
117	label *lb;
118
119	for (i = 0; i < ll->ll_nlabels; i++) {
120		if (ll->ll_label[i].lb_type == type &&
121			strcmp(ll->ll_label[i].lb_str, str) == 0)
122			return i;
123	}
124	RESIZE(ll->ll_label, label, ll->ll_nlabels + 1);
125	if (ll->ll_label == NULL)
126		fatal("no mem to resize labellist in addlabel");
127	lb = &ll->ll_label[ll->ll_nlabels++];
128	lb->lb_type = type;
129	lb->lb_str = str; /* XXX strdup(str) ??? */
130	return lb - ll->ll_label;
131}
132
133/* Same, but rather dies than adds */
134
135int
136findlabel(ll, type, str)
137	labellist *ll;
138	int type;
139	char *str;
140{
141	int i;
142	label *lb;
143
144	for (i = 0; i < ll->ll_nlabels; i++) {
145		if (ll->ll_label[i].lb_type == type /*&&
146			strcmp(ll->ll_label[i].lb_str, str) == 0*/)
147			return i;
148	}
149	fprintf(stderr, "Label %d/'%s' not found\n", type, str);
150	abort();
151}
152
153/* Forward */
154static void translabel PROTO((grammar *, label *));
155
156void
157translatelabels(g)
158	grammar *g;
159{
160	int i;
161
162	printf("Translating labels ...\n");
163	/* Don't translate EMPTY */
164	for (i = EMPTY+1; i < g->g_ll.ll_nlabels; i++)
165		translabel(g, &g->g_ll.ll_label[i]);
166}
167
168static void
169translabel(g, lb)
170	grammar *g;
171	label *lb;
172{
173	int i;
174
175	if (debugging)
176		printf("Translating label %s ...\n", labelrepr(lb));
177
178	if (lb->lb_type == NAME) {
179		for (i = 0; i < g->g_ndfas; i++) {
180			if (strcmp(lb->lb_str, g->g_dfa[i].d_name) == 0) {
181				if (debugging)
182					printf("Label %s is non-terminal %d.\n",
183						lb->lb_str,
184						g->g_dfa[i].d_type);
185				lb->lb_type = g->g_dfa[i].d_type;
186				lb->lb_str = NULL;
187				return;
188			}
189		}
190		for (i = 0; i < (int)N_TOKENS; i++) {
191			if (strcmp(lb->lb_str, tok_name[i]) == 0) {
192				if (debugging)
193					printf("Label %s is terminal %d.\n",
194						lb->lb_str, i);
195				lb->lb_type = i;
196				lb->lb_str = NULL;
197				return;
198			}
199		}
200		printf("Can't translate NAME label '%s'\n", lb->lb_str);
201		return;
202	}
203
204	if (lb->lb_type == STRING) {
205		if (isalpha(lb->lb_str[1])) {
206			char *p, *strchr();
207			if (debugging)
208				printf("Label %s is a keyword\n", lb->lb_str);
209			lb->lb_type = NAME;
210			lb->lb_str++;
211			p = strchr(lb->lb_str, '\'');
212			if (p)
213				*p = '\0';
214		}
215		else if (lb->lb_str[2] == lb->lb_str[0]) {
216			int type = (int) tok_1char(lb->lb_str[1]);
217			if (type != OP) {
218				lb->lb_type = type;
219				lb->lb_str = NULL;
220			}
221			else
222				printf("Unknown OP label %s\n",
223					lb->lb_str);
224		}
225		else if (lb->lb_str[2] && lb->lb_str[3] == lb->lb_str[0]) {
226			int type = (int) tok_2char(lb->lb_str[1],
227						   lb->lb_str[2]);
228			if (type != OP) {
229				lb->lb_type = type;
230				lb->lb_str = NULL;
231			}
232			else
233				printf("Unknown OP label %s\n",
234					lb->lb_str);
235		}
236		else
237			printf("Can't translate STRING label %s\n",
238				lb->lb_str);
239	}
240	else
241		printf("Can't translate label '%s'\n", labelrepr(lb));
242}
243