Commit | Line | Data |
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8351eafd KM |
1 | /* b.c 4.1 82/05/07 */ |
2 | ||
3 | #include "awk.def" | |
4 | #include "stdio.h" | |
5 | #include "awk.h" | |
6 | ||
7 | extern node *op2(); | |
8 | extern struct fa *cgotofn(); | |
9 | #define MAXLIN 256 | |
10 | #define NCHARS 128 | |
11 | #define NSTATES 256 | |
12 | ||
13 | #define type(v) v->nobj | |
14 | #define left(v) v->narg[0] | |
15 | #define right(v) v->narg[1] | |
16 | #define parent(v) v->nnext | |
17 | ||
18 | #define LEAF case CCL: case NCCL: case CHAR: case DOT: | |
19 | #define UNARY case FINAL: case STAR: case PLUS: case QUEST: | |
20 | ||
21 | /* encoding in tree nodes: | |
22 | leaf (CCL, NCCL, CHAR, DOT): left is index, right contains value or pointer to value | |
23 | unary (FINAL, STAR, PLUS, QUEST): left is child, right is null | |
24 | binary (CAT, OR): left and right are children | |
25 | parent contains pointer to parent | |
26 | */ | |
27 | ||
28 | struct fa { | |
29 | int cch; | |
30 | struct fa *st; | |
31 | }; | |
32 | ||
33 | int *state[NSTATES]; | |
34 | int *foll[MAXLIN]; | |
35 | char chars[MAXLIN]; | |
36 | int setvec[MAXLIN]; | |
37 | node *point[MAXLIN]; | |
38 | ||
39 | int setcnt; | |
40 | int line; | |
41 | ||
42 | ||
43 | struct fa *makedfa(p) /* returns dfa for tree pointed to by p */ | |
44 | node *p; | |
45 | { | |
46 | node *p1; | |
47 | struct fa *fap; | |
48 | p1 = op2(CAT, op2(STAR, op2(DOT, (node *) 0, (node *) 0), (node *) 0), p); | |
49 | /* put DOT STAR in front of reg. exp. */ | |
50 | p1 = op2(FINAL, p1, (node *) 0); /* install FINAL node */ | |
51 | ||
52 | line = 0; | |
53 | penter(p1); /* enter parent pointers and leaf indices */ | |
54 | point[line] = p1; /* FINAL node */ | |
55 | setvec[0] = 1; /* for initial DOT STAR */ | |
56 | cfoll(p1); /* set up follow sets */ | |
57 | fap = cgotofn(); | |
58 | freetr(p1); /* add this when alloc works */ | |
59 | return(fap); | |
60 | } | |
61 | ||
62 | penter(p) /* set up parent pointers and leaf indices */ | |
63 | node *p; | |
64 | { | |
65 | switch(type(p)) { | |
66 | LEAF | |
67 | left(p) = (node *) line; | |
68 | point[line++] = p; | |
69 | break; | |
70 | UNARY | |
71 | penter(left(p)); | |
72 | parent(left(p)) = p; | |
73 | break; | |
74 | case CAT: | |
75 | case OR: | |
76 | penter(left(p)); | |
77 | penter(right(p)); | |
78 | parent(left(p)) = p; | |
79 | parent(right(p)) = p; | |
80 | break; | |
81 | default: | |
82 | error(FATAL, "unknown type %d in penter\n", type(p)); | |
83 | break; | |
84 | } | |
85 | } | |
86 | ||
87 | freetr(p) /* free parse tree and follow sets */ | |
88 | node *p; | |
89 | { | |
90 | switch(type(p)) { | |
91 | LEAF | |
92 | xfree(foll[(int) left(p)]); | |
93 | xfree(p); | |
94 | break; | |
95 | UNARY | |
96 | freetr(left(p)); | |
97 | xfree(p); | |
98 | break; | |
99 | case CAT: | |
100 | case OR: | |
101 | freetr(left(p)); | |
102 | freetr(right(p)); | |
103 | xfree(p); | |
104 | break; | |
105 | default: | |
106 | error(FATAL, "unknown type %d in freetr", type(p)); | |
107 | break; | |
108 | } | |
109 | } | |
110 | char *cclenter(p) | |
111 | register char *p; | |
112 | { | |
113 | register i, c; | |
114 | char *op; | |
115 | ||
116 | op = p; | |
117 | i = 0; | |
118 | while ((c = *p++) != 0) { | |
119 | if (c == '-' && i > 0 && chars[i-1] != 0) { | |
120 | if (*p != 0) { | |
121 | c = chars[i-1]; | |
122 | while (c < *p) { | |
123 | if (i >= MAXLIN) | |
124 | overflo(); | |
125 | chars[i++] = ++c; | |
126 | } | |
127 | p++; | |
128 | continue; | |
129 | } | |
130 | } | |
131 | if (i >= MAXLIN) | |
132 | overflo(); | |
133 | chars[i++] = c; | |
134 | } | |
135 | chars[i++] = '\0'; | |
136 | dprintf("cclenter: in = |%s|, out = |%s|\n", op, chars, NULL); | |
137 | xfree(op); | |
138 | return(tostring(chars)); | |
139 | } | |
140 | ||
141 | overflo() | |
142 | { | |
143 | error(FATAL, "regular expression too long\n"); | |
144 | } | |
145 | ||
146 | cfoll(v) /* enter follow set of each leaf of vertex v into foll[leaf] */ | |
147 | register node *v; | |
148 | { | |
149 | register i; | |
150 | int prev; | |
151 | int *add(); | |
152 | ||
153 | switch(type(v)) { | |
154 | LEAF | |
155 | setcnt = 0; | |
156 | for (i=1; i<=line; i++) | |
157 | setvec[i] = 0; | |
158 | follow(v); | |
159 | if (notin(foll, ( (int) left(v))-1, &prev)) { | |
160 | foll[(int) left(v)] = add(setcnt); | |
161 | } | |
162 | else | |
163 | foll[ (int) left(v)] = foll[prev]; | |
164 | break; | |
165 | UNARY | |
166 | cfoll(left(v)); | |
167 | break; | |
168 | case CAT: | |
169 | case OR: | |
170 | cfoll(left(v)); | |
171 | cfoll(right(v)); | |
172 | break; | |
173 | default: | |
174 | error(FATAL, "unknown type %d in cfoll", type(v)); | |
175 | } | |
176 | } | |
177 | ||
178 | first(p) /* collects initially active leaves of p into setvec */ | |
179 | register node *p; /* returns 0 or 1 depending on whether p matches empty string */ | |
180 | { | |
181 | register b; | |
182 | ||
183 | switch(type(p)) { | |
184 | LEAF | |
185 | if (setvec[(int) left(p)] != 1) { | |
186 | setvec[(int) left(p)] = 1; | |
187 | setcnt++; | |
188 | } | |
189 | if (type(p) == CCL && (*(char *) right(p)) == '\0') | |
190 | return(0); /* empty CCL */ | |
191 | else return(1); | |
192 | case FINAL: | |
193 | case PLUS: | |
194 | if (first(left(p)) == 0) return(0); | |
195 | return(1); | |
196 | case STAR: | |
197 | case QUEST: | |
198 | first(left(p)); | |
199 | return(0); | |
200 | case CAT: | |
201 | if (first(left(p)) == 0 && first(right(p)) == 0) return(0); | |
202 | return(1); | |
203 | case OR: | |
204 | b = first(right(p)); | |
205 | if (first(left(p)) == 0 || b == 0) return(0); | |
206 | return(1); | |
207 | } | |
208 | error(FATAL, "unknown type %d in first\n", type(p)); | |
209 | return(-1); | |
210 | } | |
211 | ||
212 | follow(v) | |
213 | node *v; /* collects leaves that can follow v into setvec */ | |
214 | { | |
215 | node *p; | |
216 | ||
217 | if (type(v) == FINAL) | |
218 | return; | |
219 | p = parent(v); | |
220 | switch (type(p)) { | |
221 | case STAR: | |
222 | case PLUS: first(v); | |
223 | follow(p); | |
224 | return; | |
225 | ||
226 | case OR: | |
227 | case QUEST: follow(p); | |
228 | return; | |
229 | ||
230 | case CAT: if (v == left(p)) { /* v is left child of p */ | |
231 | if (first(right(p)) == 0) { | |
232 | follow(p); | |
233 | return; | |
234 | } | |
235 | } | |
236 | else /* v is right child */ | |
237 | follow(p); | |
238 | return; | |
239 | case FINAL: if (setvec[line] != 1) { | |
240 | setvec[line] = 1; | |
241 | setcnt++; | |
242 | } | |
243 | return; | |
244 | } | |
245 | } | |
246 | ||
247 | member(c, s) /* is c in s? */ | |
248 | register char c, *s; | |
249 | { | |
250 | while (*s) | |
251 | if (c == *s++) | |
252 | return(1); | |
253 | return(0); | |
254 | } | |
255 | ||
256 | notin(array, n, prev) /* is setvec in array[0] thru array[n]? */ | |
257 | int **array; | |
258 | int *prev; { | |
259 | register i, j; | |
260 | int *ptr; | |
261 | for (i=0; i<=n; i++) { | |
262 | ptr = array[i]; | |
263 | if (*ptr == setcnt) { | |
264 | for (j=0; j < setcnt; j++) | |
265 | if (setvec[*(++ptr)] != 1) goto nxt; | |
266 | *prev = i; | |
267 | return(0); | |
268 | } | |
269 | nxt: ; | |
270 | } | |
271 | return(1); | |
272 | } | |
273 | ||
274 | int *add(n) { /* remember setvec */ | |
275 | int *ptr, *p; | |
276 | register i; | |
277 | if ((p = ptr = (int *) malloc((n+1)*sizeof(int))) == NULL) | |
278 | overflo(); | |
279 | *ptr = n; | |
280 | dprintf("add(%d)\n", n, NULL, NULL); | |
281 | for (i=1; i <= line; i++) | |
282 | if (setvec[i] == 1) { | |
283 | *(++ptr) = i; | |
284 | dprintf(" ptr = %o, *ptr = %d, i = %d\n", ptr, *ptr, i); | |
285 | } | |
286 | dprintf("\n", NULL, NULL, NULL); | |
287 | return(p); | |
288 | } | |
289 | ||
290 | struct fa *cgotofn() | |
291 | { | |
292 | register i, k; | |
293 | register int *ptr; | |
294 | char c; | |
295 | char *p; | |
296 | node *cp; | |
297 | int j, n, s, ind, numtrans; | |
298 | int finflg; | |
299 | int curpos, num, prev; | |
300 | struct fa *where[NSTATES]; | |
301 | ||
302 | int fatab[257]; | |
303 | struct fa *pfa; | |
304 | ||
305 | char index[MAXLIN]; | |
306 | char iposns[MAXLIN]; | |
307 | int sposns[MAXLIN]; | |
308 | int spmax, spinit; | |
309 | ||
310 | char symbol[NCHARS]; | |
311 | char isyms[NCHARS]; | |
312 | char ssyms[NCHARS]; | |
313 | int ssmax, ssinit; | |
314 | ||
315 | for (i=0; i<=line; i++) index[i] = iposns[i] = setvec[i] = 0; | |
316 | for (i=0; i<NCHARS; i++) isyms[i] = symbol[i] = 0; | |
317 | setcnt = 0; | |
318 | /* compute initial positions and symbols of state 0 */ | |
319 | ssmax = 0; | |
320 | ptr = state[0] = foll[0]; | |
321 | spinit = *ptr; | |
322 | for (i=0; i<spinit; i++) { | |
323 | curpos = *(++ptr); | |
324 | sposns[i] = curpos; | |
325 | iposns[curpos] = 1; | |
326 | cp = point[curpos]; | |
327 | dprintf("i = %d, spinit = %d, curpos = %d\n", i, spinit, curpos); | |
328 | switch (type(cp)) { | |
329 | case CHAR: | |
330 | k = (int) right(cp); | |
331 | if (isyms[k] != 1) { | |
332 | isyms[k] = 1; | |
333 | ssyms[ssmax++] = k; | |
334 | } | |
335 | break; | |
336 | case DOT: | |
337 | for (k=1; k<NCHARS; k++) { | |
338 | if (k != HAT) { | |
339 | if (isyms[k] != 1) { | |
340 | isyms[k] = 1; | |
341 | ssyms[ssmax++] = k; | |
342 | } | |
343 | } | |
344 | } | |
345 | break; | |
346 | case CCL: | |
347 | for (p = (char *) right(cp); *p; p++) { | |
348 | if (*p != HAT) { | |
349 | if (isyms[*p] != 1) { | |
350 | isyms[*p] = 1; | |
351 | ssyms[ssmax++] = *p; | |
352 | } | |
353 | } | |
354 | } | |
355 | break; | |
356 | case NCCL: | |
357 | for (k=1; k<NCHARS; k++) { | |
358 | if (k != HAT && !member(k, (char *) right(cp))) { | |
359 | if (isyms[k] != 1) { | |
360 | isyms[k] = 1; | |
361 | ssyms[ssmax++] = k; | |
362 | } | |
363 | } | |
364 | } | |
365 | } | |
366 | } | |
367 | ssinit = ssmax; | |
368 | n = 0; | |
369 | for (s=0; s<=n; s++) { | |
370 | dprintf("s = %d\n", s, NULL, NULL); | |
371 | ind = 0; | |
372 | numtrans = 0; | |
373 | finflg = 0; | |
374 | if (*(state[s] + *state[s]) == line) { /* s final? */ | |
375 | finflg = 1; | |
376 | goto tenter; | |
377 | } | |
378 | spmax = spinit; | |
379 | ssmax = ssinit; | |
380 | ptr = state[s]; | |
381 | num = *ptr; | |
382 | for (i=0; i<num; i++) { | |
383 | curpos = *(++ptr); | |
384 | if (iposns[curpos] != 1 && index[curpos] != 1) { | |
385 | index[curpos] = 1; | |
386 | sposns[spmax++] = curpos; | |
387 | } | |
388 | cp = point[curpos]; | |
389 | switch (type(cp)) { | |
390 | case CHAR: | |
391 | k = (int) right(cp); | |
392 | if (isyms[k] == 0 && symbol[k] == 0) { | |
393 | symbol[k] = 1; | |
394 | ssyms[ssmax++] = k; | |
395 | } | |
396 | break; | |
397 | case DOT: | |
398 | for (k=1; k<NCHARS; k++) { | |
399 | if (k != HAT) { | |
400 | if (isyms[k] == 0 && symbol[k] == 0) { | |
401 | symbol[k] = 1; | |
402 | ssyms[ssmax++] = k; | |
403 | } | |
404 | } | |
405 | } | |
406 | break; | |
407 | case CCL: | |
408 | for (p = (char *) right(cp); *p; p++) { | |
409 | if (*p != HAT) { | |
410 | if (isyms[*p] == 0 && symbol[*p] == 0) { | |
411 | symbol[*p] = 1; | |
412 | ssyms[ssmax++] = *p; | |
413 | } | |
414 | } | |
415 | } | |
416 | break; | |
417 | case NCCL: | |
418 | for (k=1; k<NCHARS; k++) { | |
419 | if (k != HAT && !member(k, (char *) right(cp))) { | |
420 | if (isyms[k] == 0 && symbol[k] == 0) { | |
421 | symbol[k] = 1; | |
422 | ssyms[ssmax++] = k; | |
423 | } | |
424 | } | |
425 | } | |
426 | } | |
427 | } | |
428 | for (j=0; j<ssmax; j++) { /* nextstate(s, ssyms[j]) */ | |
429 | c = ssyms[j]; | |
430 | symbol[c] = 0; | |
431 | setcnt = 0; | |
432 | for (k=0; k<=line; k++) setvec[k] = 0; | |
433 | for (i=0; i<spmax; i++) { | |
434 | index[sposns[i]] = 0; | |
435 | cp = point[sposns[i]]; | |
436 | if ((k = type(cp)) != FINAL) | |
437 | if (k == CHAR && c == (int) right(cp) | |
438 | || k == DOT | |
439 | || k == CCL && member(c, (char *) right(cp)) | |
440 | || k == NCCL && !member(c, (char *) right(cp))) { | |
441 | ptr = foll[sposns[i]]; | |
442 | num = *ptr; | |
443 | for (k=0; k<num; k++) { | |
444 | if (setvec[*(++ptr)] != 1 | |
445 | && iposns[*ptr] != 1) { | |
446 | setvec[*ptr] = 1; | |
447 | setcnt++; | |
448 | } | |
449 | } | |
450 | } | |
451 | } /* end nextstate */ | |
452 | if (notin(state, n, &prev)) { | |
453 | if (n >= NSTATES) { | |
454 | dprintf("cgotofn: notin; state = %d, n = %d\n", state, n, NULL); | |
455 | overflo(); | |
456 | } | |
457 | state[++n] = add(setcnt); | |
458 | dprintf(" delta(%d,%o) = %d", s,c,n); | |
459 | dprintf(", ind = %d\n", ind+1, NULL, NULL); | |
460 | fatab[++ind] = c; | |
461 | fatab[++ind] = n; | |
462 | numtrans++; | |
463 | } | |
464 | else { | |
465 | if (prev != 0) { | |
466 | dprintf(" delta(%d,%o) = %d", s,c,prev); | |
467 | dprintf(", ind = %d\n", ind+1, NULL, NULL); | |
468 | fatab[++ind] = c; | |
469 | fatab[++ind] = prev; | |
470 | numtrans++; | |
471 | } | |
472 | } | |
473 | } | |
474 | tenter: | |
475 | if ((pfa = (struct fa *) malloc((numtrans + 1) * sizeof(struct fa))) == NULL) | |
476 | overflo(); | |
477 | where[s] = pfa; | |
478 | if (finflg) | |
479 | pfa->cch = -1; /* s is a final state */ | |
480 | else | |
481 | pfa->cch = numtrans; | |
482 | pfa->st = 0; | |
483 | for (i=1, pfa += 1; i<=numtrans; i++, pfa++) { | |
484 | pfa->cch = fatab[2*i-1]; | |
485 | pfa->st = (struct fa *) fatab[2*i]; | |
486 | } | |
487 | } | |
488 | for (i=0; i<=n; i++) { | |
489 | xfree(state[i]); /* free state[i] */ | |
490 | pfa = where[i]; | |
491 | pfa->st = where[0]; | |
492 | dprintf("state %d: (%o)\n", i, pfa, NULL); | |
493 | dprintf(" numtrans = %d, default = %o\n", pfa->cch, pfa->st, NULL); | |
494 | for (k=1; k<=pfa->cch; k++) { | |
495 | (pfa+k)->st = where[ (int) (pfa+k)->st]; | |
496 | dprintf(" char = %o, nextstate = %o\n",(pfa+k)->cch, (pfa+k)->st, NULL); | |
497 | } | |
498 | } | |
499 | pfa = where[0]; | |
500 | if ((num = pfa->cch) < 0) | |
501 | return(where[0]); | |
502 | for (pfa += num; num; num--, pfa--) | |
503 | if (pfa->cch == HAT) { | |
504 | return(pfa->st); | |
505 | } | |
506 | return(where[0]); | |
507 | } | |
508 | ||
509 | match(pfa, p) | |
510 | register struct fa *pfa; | |
511 | register char *p; | |
512 | { | |
513 | register count; | |
514 | char c; | |
515 | if (p == 0) return(0); | |
516 | if (pfa->cch == 1) { /* fast test for first character, if possible */ | |
517 | c = (++pfa)->cch; | |
518 | do | |
519 | if (c == *p) { | |
520 | p++; | |
521 | pfa = pfa->st; | |
522 | goto adv; | |
523 | } | |
524 | while (*p++ != 0); | |
525 | return(0); | |
526 | } | |
527 | adv: if ((count = pfa->cch) < 0) return(1); | |
528 | do { | |
529 | for (pfa += count; count; count--, pfa--) | |
530 | if (pfa->cch == *p) { | |
531 | break; | |
532 | } | |
533 | pfa = pfa->st; | |
534 | if ((count = pfa->cch) < 0) return(1); | |
535 | } while(*p++ != 0); | |
536 | return(0); | |
537 | } |