xref: /netbsd-src/usr.bin/xlint/lint1/init.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: init.c,v 1.27 2015/07/28 17:55:13 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1994, 1995 Jochen Pohl
5  * 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 Jochen Pohl for
18  *	The NetBSD Project.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #if HAVE_NBTOOL_CONFIG_H
35 #include "nbtool_config.h"
36 #endif
37 
38 #include <sys/cdefs.h>
39 #if defined(__RCSID) && !defined(lint)
40 __RCSID("$NetBSD: init.c,v 1.27 2015/07/28 17:55:13 christos Exp $");
41 #endif
42 
43 #include <stdlib.h>
44 #include <string.h>
45 #include <ctype.h>
46 
47 #include "lint1.h"
48 
49 /*
50  * initerr is set as soon as a fatal error occurred in an initialisation.
51  * The effect is that the rest of the initialisation is ignored (parsed
52  * by yacc, expression trees built, but no initialisation takes place).
53  */
54 int	initerr;
55 
56 /* Pointer to the symbol which is to be initialized. */
57 sym_t	*initsym;
58 
59 /* Points to the top element of the initialisation stack. */
60 istk_t	*initstk;
61 
62 typedef struct namlist {
63 	const char *n_name;
64 	struct namlist *n_prev;
65 	struct namlist *n_next;
66 } namlist_t;
67 
68 /* Points to a c9x named member; */
69 namlist_t	*namedmem = NULL;
70 
71 
72 static	void	popi2(void);
73 static	void	popinit(int);
74 static	void	pushinit(void);
75 static	void	testinit(void);
76 static	void	nextinit(int);
77 static	int	strginit(tnode_t *);
78 static	void	memberpop(void);
79 
80 #ifndef DEBUG
81 #define DPRINTF(a)
82 #else
83 #define DPRINTF(a) printf a
84 #endif
85 
86 void
87 memberpush(sb)
88 	sbuf_t *sb;
89 {
90 	namlist_t *nam = xcalloc(1, sizeof (namlist_t));
91 	nam->n_name = sb->sb_name;
92 	DPRINTF(("%s: %s %p\n", __func__, nam->n_name, nam));
93 	if (namedmem == NULL) {
94 		nam->n_prev = nam->n_next = nam;
95 		namedmem = nam;
96 	} else {
97 		namedmem->n_prev->n_next = nam;
98 		nam->n_prev = namedmem->n_prev;
99 		nam->n_next = namedmem;
100 		namedmem->n_prev = nam;
101 	}
102 }
103 
104 static void
105 memberpop(void)
106 {
107 	DPRINTF(("%s: %s %p\n", __func__, namedmem->n_name, namedmem));
108 	if (namedmem->n_next == namedmem) {
109 		free(namedmem);
110 		namedmem = NULL;
111 	} else {
112 		namlist_t *nam = namedmem;
113 		namedmem = namedmem->n_next;
114 		namedmem->n_next = nam->n_next;
115 		namedmem->n_prev = nam->n_prev;
116 		free(nam);
117 	}
118 }
119 
120 
121 /*
122  * Initialize the initialisation stack by putting an entry for the variable
123  * which is to be initialized on it.
124  */
125 void
126 prepinit(void)
127 {
128 	istk_t	*istk;
129 
130 	if (initerr)
131 		return;
132 
133 	/* free memory used in last initialisation */
134 	while ((istk = initstk) != NULL) {
135 		initstk = istk->i_nxt;
136 		free(istk);
137 	}
138 
139 	/*
140 	 * If the type which is to be initialized is an incomplete type,
141 	 * it must be duplicated.
142 	 */
143 	if (initsym->s_type->t_tspec == ARRAY && incompl(initsym->s_type))
144 		initsym->s_type = duptyp(initsym->s_type);
145 
146 	istk = initstk = xcalloc(1, sizeof (istk_t));
147 	istk->i_subt = initsym->s_type;
148 	istk->i_cnt = 1;
149 
150 }
151 
152 static void
153 popi2(void)
154 {
155 #ifdef DEBUG
156 	char	buf[64];
157 #endif
158 	istk_t	*istk;
159 	sym_t	*m;
160 
161 	DPRINTF(("%s+(%s): brace=%d count=%d namedmem %d\n", __func__,
162 	    tyname(buf, sizeof(buf),
163 	    initstk->i_type ? initstk->i_type : initstk->i_subt),
164 	    initstk->i_brace, initstk->i_cnt, initstk->i_namedmem));
165 	initstk = (istk = initstk)->i_nxt;
166 	free(istk);
167 
168 	istk = initstk;
169 	if (istk == NULL)
170 		LERROR("popi2()");
171 
172 	DPRINTF(("%s-(%s): brace=%d count=%d namedmem %d\n", __func__,
173 	    tyname(buf, sizeof(buf),
174 	    initstk->i_type ? initstk->i_type : initstk->i_subt),
175 	    initstk->i_brace, initstk->i_cnt, initstk->i_namedmem));
176 
177 	istk->i_cnt--;
178 	if (istk->i_cnt < 0)
179 		LERROR("popi2()");
180 
181 	DPRINTF(("%s(): %d %s\n", __func__, istk->i_cnt,
182 	    namedmem ? namedmem->n_name : "*null*"));
183 	if (istk->i_cnt >= 0 && namedmem != NULL) {
184 		DPRINTF(("%s(): %d %s %s\n", __func__, istk->i_cnt,
185 		    tyname(buf, sizeof(buf), istk->i_type), namedmem->n_name));
186 		for (m = istk->i_type->t_str->memb; m != NULL; m = m->s_nxt) {
187 			DPRINTF(("%s(): pop [%s %s]\n", __func__,
188 			    namedmem->n_name, m->s_name));
189 			if (m->s_field && m->s_name == unnamed)
190 				continue;
191 			if (strcmp(m->s_name, namedmem->n_name) == 0) {
192 				istk->i_subt = m->s_type;
193 				istk->i_cnt++;
194 				memberpop();
195 				return;
196 			}
197 		}
198 		error(101, namedmem->n_name);
199 		DPRINTF(("%s(): namedmem %s\n", __func__, namedmem->n_name));
200 		memberpop();
201 		istk->i_namedmem = 1;
202 		return;
203 	}
204 	/*
205 	 * If the removed element was a structure member, we must go
206 	 * to the next structure member.
207 	 */
208 	if (istk->i_cnt > 0 && istk->i_type->t_tspec == STRUCT &&
209 	    !istk->i_namedmem) {
210 		do {
211 			m = istk->i_mem = istk->i_mem->s_nxt;
212 			if (m == NULL)
213 				LERROR("popi2()");
214 			DPRINTF(("%s(): pop %s\n", __func__, m->s_name));
215 		} while (m->s_field && m->s_name == unnamed);
216 		istk->i_subt = m->s_type;
217 	}
218 }
219 
220 static void
221 popinit(int brace)
222 {
223 	DPRINTF(("%s(%d)\n", __func__, brace));
224 
225 	if (brace) {
226 		/*
227 		 * Take all entries, including the first which requires
228 		 * a closing brace, from the stack.
229 		 */
230 		DPRINTF(("%s: brace\n", __func__));
231 		do {
232 			brace = initstk->i_brace;
233 			DPRINTF(("%s: loop brace %d\n", __func__, brace));
234 			popi2();
235 		} while (!brace);
236 		DPRINTF(("%s: brace done\n", __func__));
237 	} else {
238 		/*
239 		 * Take all entries which cannot be used for further
240 		 * initializers from the stack, but do this only if
241 		 * they do not require a closing brace.
242 		 */
243 		DPRINTF(("%s: no brace\n", __func__));
244 		while (!initstk->i_brace &&
245 		       initstk->i_cnt == 0 && !initstk->i_nolimit) {
246 			popi2();
247 		}
248 		DPRINTF(("%s: no brace done\n", __func__));
249 	}
250 }
251 
252 static void
253 pushinit(void)
254 {
255 #ifdef DEBUG
256 	char	buf[64];
257 #endif
258 	istk_t	*istk, *inxt;
259 	int	cnt;
260 	sym_t	*m;
261 
262 	istk = initstk;
263 
264 	/* Extend an incomplete array type by one element */
265 	if (istk->i_cnt == 0) {
266 		DPRINTF(("%s(extend) %s\n", __func__, tyname(buf, sizeof(buf),
267 		    istk->i_type)));
268 		/*
269 		 * Inside of other aggregate types must not be an incomplete
270 		 * type.
271 		 */
272 		if (istk->i_nxt->i_nxt != NULL)
273 			LERROR("pushinit()");
274 		istk->i_cnt = 1;
275 		if (istk->i_type->t_tspec != ARRAY)
276 			LERROR("pushinit()");
277 		istk->i_type->t_dim++;
278 		/* from now its an complete type */
279 		setcompl(istk->i_type, 0);
280 	}
281 
282 	if (istk->i_cnt <= 0)
283 		LERROR("pushinit()");
284 	if (istk->i_type != NULL && issclt(istk->i_type->t_tspec))
285 		LERROR("pushinit()");
286 
287 	initstk = xcalloc(1, sizeof (istk_t));
288 	initstk->i_nxt = istk;
289 	initstk->i_type = istk->i_subt;
290 	if (initstk->i_type->t_tspec == FUNC)
291 		LERROR("pushinit()");
292 
293 again:
294 	istk = initstk;
295 
296 	DPRINTF(("%s(%s)\n", __func__, tyname(buf, sizeof(buf), istk->i_type)));
297 	switch (istk->i_type->t_tspec) {
298 	case ARRAY:
299 		if (namedmem) {
300 			DPRINTF(("%s: ARRAY %s brace=%d\n", __func__,
301 			    namedmem->n_name, istk->i_brace));
302 			goto pop;
303 		} else if (istk->i_nxt->i_namedmem) {
304 			istk->i_brace = 1;
305 			DPRINTF(("%s ARRAY brace=%d, namedmem=%d\n", __func__,
306 			    istk->i_brace, istk->i_nxt->i_namedmem));
307 		}
308 
309 		if (incompl(istk->i_type) && istk->i_nxt->i_nxt != NULL) {
310 			/* initialisation of an incomplete type */
311 			error(175);
312 			initerr = 1;
313 			return;
314 		}
315 		istk->i_subt = istk->i_type->t_subt;
316 		istk->i_nolimit = incompl(istk->i_type);
317 		istk->i_cnt = istk->i_type->t_dim;
318 		DPRINTF(("%s: elements array %s[%d] %s\n", __func__,
319 		    tyname(buf, sizeof(buf), istk->i_subt), istk->i_cnt,
320 		    namedmem ? namedmem->n_name : "*none*"));
321 		break;
322 	case UNION:
323 		if (tflag)
324 			/* initialisation of union is illegal in trad. C */
325 			warning(238);
326 		/* FALLTHROUGH */
327 	case STRUCT:
328 		if (incompl(istk->i_type)) {
329 			/* initialisation of an incomplete type */
330 			error(175);
331 			initerr = 1;
332 			return;
333 		}
334 		cnt = 0;
335 		DPRINTF(("%s: 2. member lookup %s %s i_namedmem=%d\n", __func__,
336 		    tyname(buf, sizeof(buf), istk->i_type),
337 		    namedmem ? namedmem->n_name : "*none*", istk->i_namedmem));
338 		for (m = istk->i_type->t_str->memb; m != NULL; m = m->s_nxt) {
339 			if (m->s_field && m->s_name == unnamed)
340 				continue;
341 			if (namedmem != NULL) {
342 				DPRINTF(("%s():[member:%s, looking:%s]\n",
343 				    __func__, m->s_name, namedmem->n_name));
344 				if (strcmp(m->s_name, namedmem->n_name) == 0) {
345 					cnt++;
346 					break;
347 				} else
348 					continue;
349 			}
350 			if (++cnt == 1) {
351 				istk->i_mem = m;
352 				istk->i_subt = m->s_type;
353 			}
354 		}
355 		if (namedmem != NULL) {
356 			if (m == NULL) {
357 				DPRINTF(("%s(): struct pop\n", __func__));
358 				goto pop;
359 			}
360 			istk->i_mem = m;
361 			istk->i_subt = m->s_type;
362 			istk->i_namedmem = 1;
363 			DPRINTF(("%s(): namedmem %s\n", __func__,
364 			    namedmem->n_name));
365 			memberpop();
366 			cnt = istk->i_type->t_tspec == STRUCT ? 2 : 1;
367 		}
368 		istk->i_brace = 1;
369 		DPRINTF(("%s(): %s brace=%d\n", __func__,
370 		    tyname(buf, sizeof(buf),
371 		    istk->i_type ? istk->i_type : istk->i_subt),
372 		    istk->i_brace));
373 		if (cnt == 0) {
374 			/* cannot init. struct/union with no named member */
375 			error(179);
376 			initerr = 1;
377 			return;
378 		}
379 		istk->i_cnt = istk->i_type->t_tspec == STRUCT ? cnt : 1;
380 		break;
381 	default:
382 		if (namedmem) {
383 			DPRINTF(("%s(): pop\n", __func__));
384 	pop:
385 			inxt = initstk->i_nxt;
386 			free(istk);
387 			initstk = inxt;
388 			goto again;
389 		}
390 		istk->i_cnt = 1;
391 		break;
392 	}
393 }
394 
395 static void
396 testinit(void)
397 {
398 	istk_t	*istk;
399 
400 	istk = initstk;
401 
402 	/*
403 	 * If a closing brace is expected we have at least one initializer
404 	 * too much.
405 	 */
406 	if (istk->i_cnt == 0 && !istk->i_nolimit && !istk->i_namedmem) {
407 		switch (istk->i_type->t_tspec) {
408 		case ARRAY:
409 			/* too many array initializers */
410 			error(173, istk->i_type->t_dim);
411 			break;
412 		case STRUCT:
413 		case UNION:
414 			/* too many struct/union initializers */
415 			error(172);
416 			break;
417 		default:
418 			/* too many initializers */
419 			error(174);
420 			break;
421 		}
422 		initerr = 1;
423 	}
424 }
425 
426 static void
427 nextinit(int brace)
428 {
429 	char buf[64];
430 
431 	DPRINTF(("%s(%d)\n", __func__, brace));
432 	if (!brace) {
433 		if (initstk->i_type == NULL &&
434 		    !issclt(initstk->i_subt->t_tspec)) {
435 			/* {}-enclosed initializer required */
436 			error(181);
437 		}
438 		/*
439 		 * Make sure an entry with a scalar type is at the top
440 		 * of the stack.
441 		 */
442 		if (!initerr)
443 			testinit();
444 		while (!initerr && (initstk->i_type == NULL ||
445 				    !issclt(initstk->i_type->t_tspec))) {
446 			if (!initerr)
447 				pushinit();
448 		}
449 	} else {
450 		if (initstk->i_type != NULL &&
451 		    issclt(initstk->i_type->t_tspec)) {
452 			/* invalid initializer */
453 			error(176, tyname(buf, sizeof(buf), initstk->i_type));
454 			initerr = 1;
455 		}
456 		if (!initerr)
457 			testinit();
458 		if (!initerr)
459 			pushinit();
460 		if (!initerr) {
461 			initstk->i_brace = 1;
462 			DPRINTF(("%s(): %p %s brace=%d\n", __func__,
463 			    namedmem, tyname(buf, sizeof(buf),
464 			    initstk->i_type ? initstk->i_type :
465 			    initstk->i_subt), initstk->i_brace));
466 		}
467 	}
468 }
469 
470 void
471 initlbr(void)
472 {
473 	DPRINTF(("%s\n", __func__));
474 
475 	if (initerr)
476 		return;
477 
478 	if ((initsym->s_scl == AUTO || initsym->s_scl == REG) &&
479 	    initstk->i_nxt == NULL) {
480 		if (tflag && !issclt(initstk->i_subt->t_tspec))
481 			/* no automatic aggregate initialization in trad. C*/
482 			warning(188);
483 	}
484 
485 	/*
486 	 * Remove all entries which cannot be used for further initializers
487 	 * and do not expect a closing brace.
488 	 */
489 	popinit(0);
490 
491 	nextinit(1);
492 }
493 
494 void
495 initrbr(void)
496 {
497 	DPRINTF(("%s\n", __func__));
498 
499 	if (initerr)
500 		return;
501 
502 	popinit(1);
503 }
504 
505 void
506 mkinit(tnode_t *tn)
507 {
508 	ptrdiff_t offs;
509 	sym_t	*sym;
510 	tspec_t	lt, rt;
511 	tnode_t	*ln;
512 	struct	mbl *tmem;
513 	scl_t	sc;
514 #ifdef DEBUG
515 	char	buf[64], sbuf[64];
516 #endif
517 
518 	DPRINTF(("%s(%s %s)\n", __func__, tyname(buf, sizeof(buf), tn->tn_type),
519 	    prtnode(sbuf, sizeof(sbuf), tn)));
520 	if (initerr || tn == NULL)
521 		return;
522 
523 	sc = initsym->s_scl;
524 
525 	/*
526 	 * Do not test for automatic aggregate initialisation. If the
527 	 * initializer starts with a brace we have the warning already.
528 	 * If not, an error will be printed that the initializer must
529 	 * be enclosed by braces.
530 	 */
531 
532 	/*
533 	 * Local initialisation of non-array-types with only one expression
534 	 * without braces is done by ASSIGN
535 	 */
536 	if ((sc == AUTO || sc == REG) &&
537 	    initsym->s_type->t_tspec != ARRAY && initstk->i_nxt == NULL) {
538 		ln = getnnode(initsym, 0);
539 		ln->tn_type = tduptyp(ln->tn_type);
540 		ln->tn_type->t_const = 0;
541 		tn = build(ASSIGN, ln, tn);
542 		expr(tn, 0, 0, 0);
543 		return;
544 	}
545 
546 	/*
547 	 * Remove all entries which cannot be used for further initializers
548 	 * and do not require a closing brace.
549 	 */
550 	popinit(0);
551 
552 	/* Initialisations by strings are done in strginit(). */
553 	if (strginit(tn))
554 		return;
555 
556 	nextinit(0);
557 	if (initerr || tn == NULL)
558 		return;
559 
560 	initstk->i_cnt--;
561 	DPRINTF(("%s() cnt=%d tn=%p\n", __func__, initstk->i_cnt, tn));
562 	/* Create a temporary node for the left side. */
563 	ln = tgetblk(sizeof (tnode_t));
564 	ln->tn_op = NAME;
565 	ln->tn_type = tduptyp(initstk->i_type);
566 	ln->tn_type->t_const = 0;
567 	ln->tn_lvalue = 1;
568 	ln->tn_sym = initsym;		/* better than nothing */
569 
570 	tn = cconv(tn);
571 
572 	lt = ln->tn_type->t_tspec;
573 	rt = tn->tn_type->t_tspec;
574 
575 	if (!issclt(lt))
576 		LERROR("mkinit()");
577 
578 	if (!typeok(INIT, 0, ln, tn))
579 		return;
580 
581 	/*
582 	 * Store the tree memory. This is nessesary because otherwise
583 	 * expr() would free it.
584 	 */
585 	tmem = tsave();
586 	expr(tn, 1, 0, 1);
587 	trestor(tmem);
588 
589 	if (isityp(lt) && ln->tn_type->t_isfield && !isityp(rt)) {
590 		/*
591 		 * Bit-fields can be initialized in trad. C only by integer
592 		 * constants.
593 		 */
594 		if (tflag)
595 			/* bit-field initialisation is illegal in trad. C */
596 			warning(186);
597 	}
598 
599 	if (lt != rt || (initstk->i_type->t_isfield && tn->tn_op == CON))
600 		tn = convert(INIT, 0, initstk->i_type, tn);
601 
602 	if (tn != NULL && tn->tn_op != CON) {
603 		sym = NULL;
604 		offs = 0;
605 		if (conaddr(tn, &sym, &offs) == -1) {
606 			if (sc == AUTO || sc == REG) {
607 				/* non-constant initializer */
608 				(void)c99ism(177);
609 			} else {
610 				/* non-constant initializer */
611 				error(177);
612 			}
613 		}
614 	}
615 }
616 
617 
618 static int
619 strginit(tnode_t *tn)
620 {
621 	tspec_t	t;
622 	istk_t	*istk;
623 	int	len;
624 	strg_t	*strg;
625 
626 	if (tn->tn_op != STRING)
627 		return (0);
628 
629 	istk = initstk;
630 	strg = tn->tn_strg;
631 
632 	/*
633 	 * Check if we have an array type which can be initialized by
634 	 * the string.
635 	 */
636 	if (istk->i_subt != NULL && istk->i_subt->t_tspec == ARRAY) {
637 		DPRINTF(("%s: subt array\n", __func__));
638 		t = istk->i_subt->t_subt->t_tspec;
639 		if (!((strg->st_tspec == CHAR &&
640 		       (t == CHAR || t == UCHAR || t == SCHAR)) ||
641 		      (strg->st_tspec == WCHAR && t == WCHAR))) {
642 			return (0);
643 		}
644 		/* Put the array at top of stack */
645 		pushinit();
646 		istk = initstk;
647 	} else if (istk->i_type != NULL && istk->i_type->t_tspec == ARRAY) {
648 		DPRINTF(("%s: type array\n", __func__));
649 		t = istk->i_type->t_subt->t_tspec;
650 		if (!((strg->st_tspec == CHAR &&
651 		       (t == CHAR || t == UCHAR || t == SCHAR)) ||
652 		      (strg->st_tspec == WCHAR && t == WCHAR))) {
653 			return (0);
654 		}
655 		/*
656 		 * If the array is already partly initialized, we are
657 		 * wrong here.
658 		 */
659 		if (istk->i_cnt != istk->i_type->t_dim)
660 			return (0);
661 	} else {
662 		return (0);
663 	}
664 
665 	/* Get length without trailing NUL character. */
666 	len = strg->st_len;
667 
668 	if (istk->i_nolimit) {
669 		istk->i_nolimit = 0;
670 		istk->i_type->t_dim = len + 1;
671 		/* from now complete type */
672 		setcompl(istk->i_type, 0);
673 	} else {
674 		if (istk->i_type->t_dim < len) {
675 			/* non-null byte ignored in string initializer */
676 			warning(187);
677 		}
678 	}
679 
680 	/* In every case the array is initialized completely. */
681 	istk->i_cnt = 0;
682 
683 	return (1);
684 }
685