xref: /freebsd-11-stable/usr.bin/xlint/lint1/init.c (revision 11d38a5764295585a2472d5e861fa8abe1a11eb2)
1 /*	$NetBSD: init.c,v 1.10 2002/01/31 19:36:54 tv 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 #include <sys/cdefs.h>
35 #if defined(__RCSID) && !defined(lint)
36 __RCSID("$NetBSD: init.c,v 1.10 2002/01/31 19:36:54 tv Exp $");
37 #endif
38 __FBSDID("$FreeBSD$");
39 
40 #include <ctype.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 #include "lint1.h"
45 
46 /*
47  * initerr is set as soon as a fatal error occurred in an initialisation.
48  * The effect is that the rest of the initialisation is ignored (parsed
49  * by yacc, expression trees built, but no initialisation takes place).
50  */
51 int	initerr;
52 
53 /* Pointer to the symbol which is to be initialized. */
54 sym_t	*initsym;
55 
56 /* Points to the top element of the initialisation stack. */
57 istk_t	*initstk;
58 
59 typedef struct namlist {
60 	const char *n_name;
61 	struct namlist *n_prev;
62 	struct namlist *n_next;
63 } namlist_t;
64 
65 /* Points to a c9x named member; */
66 namlist_t	*namedmem = NULL;
67 
68 
69 static	void	popi2(void);
70 static	void	popinit(int);
71 static	void	pushinit(void);
72 static	void	testinit(void);
73 static	void	nextinit(int);
74 static	int	strginit(tnode_t *);
75 static	void	memberpop(void);
76 
77 #ifndef DEBUG
78 #define DPRINTF(a)
79 #else
80 #define DPRINTF(a) printf a
81 #endif
82 
83 void
memberpush(sb)84 memberpush(sb)
85 	sbuf_t *sb;
86 {
87 	namlist_t *nam = xcalloc(1, sizeof (namlist_t));
88 	nam->n_name = sb->sb_name;
89 	DPRINTF(("memberpush = %s\n", nam->n_name));
90 	if (namedmem == NULL) {
91 		nam->n_prev = nam->n_next = nam;
92 		namedmem = nam;
93 	} else {
94 		namedmem->n_prev->n_next = nam;
95 		nam->n_prev = namedmem->n_prev;
96 		nam->n_next = namedmem;
97 		namedmem->n_prev = nam;
98 	}
99 #if 0
100 	nam->n_next = namedmem;
101 	namedmem = nam;
102 #endif
103 }
104 
105 static void
memberpop()106 memberpop()
107 {
108 	DPRINTF(("memberpop = %s\n", namedmem->n_name));
109 	if (namedmem->n_next == namedmem) {
110 		free(namedmem);
111 		namedmem = NULL;
112 	} else {
113 		namlist_t *nam = namedmem;
114 		namedmem = namedmem->n_next;
115 		free(nam);
116 	}
117 #if 0
118 	namedmem = namedmem->n_next;
119 	free(nam);
120 #endif
121 }
122 
123 
124 /*
125  * Initialize the initialisation stack by putting an entry for the variable
126  * which is to be initialized on it.
127  */
128 void
prepinit(void)129 prepinit(void)
130 {
131 	istk_t	*istk;
132 
133 	if (initerr)
134 		return;
135 
136 	/* free memory used in last initialisation */
137 	while ((istk = initstk) != NULL) {
138 		initstk = istk->i_nxt;
139 		free(istk);
140 	}
141 
142 	/*
143 	 * If the type which is to be initialized is an incomplete type,
144 	 * it must be duplicated.
145 	 */
146 	if (initsym->s_type->t_tspec == ARRAY && incompl(initsym->s_type))
147 		initsym->s_type = duptyp(initsym->s_type);
148 
149 	istk = initstk = xcalloc(1, sizeof (istk_t));
150 	istk->i_subt = initsym->s_type;
151 	istk->i_cnt = 1;
152 
153 }
154 
155 static void
popi2(void)156 popi2(void)
157 {
158 #ifdef DEBUG
159 	char	buf[64];
160 #endif
161 	istk_t	*istk;
162 	sym_t	*m;
163 
164 	initstk = (istk = initstk)->i_nxt;
165 	if (initstk == NULL)
166 		LERROR("popi2()");
167 	free(istk);
168 
169 	istk = initstk;
170 
171 	istk->i_cnt--;
172 	if (istk->i_cnt < 0)
173 		LERROR("popi2()");
174 
175 	DPRINTF(("popi2(): %d %s\n", istk->i_cnt,
176 	    namedmem ? namedmem->n_name : "*null*"));
177 	if (istk->i_cnt >= 0 && namedmem != NULL) {
178 		DPRINTF(("popi2(): %d %s %s\n", istk->i_cnt,
179 		    tyname(buf, sizeof(buf), istk->i_type), namedmem->n_name));
180 		for (m = istk->i_type->t_str->memb; m != NULL; m = m->s_nxt) {
181 			if (m->s_field && m->s_name == unnamed)
182 				continue;
183 			if (strcmp(m->s_name, namedmem->n_name) == 0) {
184 				istk->i_subt = m->s_type;
185 				istk->i_cnt++;
186 				memberpop();
187 				return;
188 			}
189 		}
190 		error(101, namedmem->n_name);
191 		memberpop();
192 		istk->i_namedmem = 1;
193 		return;
194 	}
195 	/*
196 	 * If the removed element was a structure member, we must go
197 	 * to the next structure member.
198 	 */
199 	if (istk->i_cnt > 0 && istk->i_type->t_tspec == STRUCT &&
200 	    !istk->i_namedmem) {
201 		do {
202 			m = istk->i_mem = istk->i_mem->s_nxt;
203 			if (m == NULL)
204 				LERROR("popi2()");
205 		} while (m->s_field && m->s_name == unnamed);
206 		istk->i_subt = m->s_type;
207 	}
208 }
209 
210 static void
popinit(int brace)211 popinit(int brace)
212 {
213 	DPRINTF(("popinit(%d)\n", brace));
214 
215 	if (brace) {
216 		/*
217 		 * Take all entries, including the first which requires
218 		 * a closing brace, from the stack.
219 		 */
220 		do {
221 			brace = initstk->i_brace;
222 			popi2();
223 		} while (!brace);
224 	} else {
225 		/*
226 		 * Take all entries which cannot be used for further
227 		 * initializers from the stack, but do this only if
228 		 * they do not require a closing brace.
229 		 */
230 		while (!initstk->i_brace &&
231 		       initstk->i_cnt == 0 && !initstk->i_nolimit) {
232 			popi2();
233 		}
234 	}
235 }
236 
237 static void
pushinit(void)238 pushinit(void)
239 {
240 #ifdef DEBUG
241 	char	buf[64];
242 #endif
243 	istk_t	*istk;
244 	int	cnt;
245 	sym_t	*m;
246 
247 	istk = initstk;
248 
249 	/* Extend an incomplete array type by one element */
250 	if (istk->i_cnt == 0) {
251 		DPRINTF(("pushinit(extend) %s\n", tyname(buf, sizeof(buf),
252 		    istk->i_type)));
253 		/*
254 		 * Inside of other aggregate types must not be an incomplete
255 		 * type.
256 		 */
257 		if (istk->i_nxt->i_nxt != NULL)
258 			LERROR("pushinit()");
259 		istk->i_cnt = 1;
260 		if (istk->i_type->t_tspec != ARRAY)
261 			LERROR("pushinit()");
262 		istk->i_type->t_dim++;
263 		/* from now its a complete type */
264 		setcompl(istk->i_type, 0);
265 	}
266 
267 	if (istk->i_cnt <= 0)
268 		LERROR("pushinit()");
269 	if (istk->i_type != NULL && issclt(istk->i_type->t_tspec))
270 		LERROR("pushinit() 4");
271 
272 	initstk = xcalloc(1, sizeof (istk_t));
273 	initstk->i_nxt = istk;
274 	initstk->i_type = istk->i_subt;
275 	if (initstk->i_type->t_tspec == FUNC)
276 		LERROR("pushinit()");
277 
278 again:
279 	istk = initstk;
280 
281 	DPRINTF(("pushinit(%s)\n", tyname(buf, sizeof(buf), istk->i_type)));
282 	switch (istk->i_type->t_tspec) {
283 	case ARRAY:
284 		if (namedmem) {
285 			DPRINTF(("pushinit ARRAY %s\n", namedmem->n_name));
286 			free(istk);
287 			initstk = initstk->i_nxt;
288 			goto again;
289 		}
290 		if (incompl(istk->i_type) && istk->i_nxt->i_nxt != NULL) {
291 			/* initialisation of an incomplete type */
292 			error(175);
293 			initerr = 1;
294 			return;
295 		}
296 		istk->i_subt = istk->i_type->t_subt;
297 		istk->i_nolimit = incompl(istk->i_type);
298 		istk->i_cnt = istk->i_type->t_dim;
299 		DPRINTF(("elements array %s[%d] %s\n",
300 		    tyname(buf, sizeof(buf), istk->i_subt), istk->i_cnt,
301 		    namedmem ? namedmem->n_name : "*none*"));
302 		break;
303 	case UNION:
304 		if (tflag)
305 			/* initialisation of union is illegal in trad. C */
306 			warning(238);
307 		/* FALLTHROUGH */
308 	case STRUCT:
309 		if (incompl(istk->i_type)) {
310 			/* initialisation of an incomplete type */
311 			error(175);
312 			initerr = 1;
313 			return;
314 		}
315 		cnt = 0;
316 		DPRINTF(("2. member lookup %s %s\n",
317 		    tyname(buf, sizeof(buf), istk->i_type),
318 		    namedmem ? namedmem->n_name : "*none*"));
319 		for (m = istk->i_type->t_str->memb; m != NULL; m = m->s_nxt) {
320 			if (m->s_field && m->s_name == unnamed)
321 				continue;
322 			if (namedmem != NULL) {
323 				DPRINTF(("pushinit():[member:%s, looking:%s]\n",
324 				    m->s_name, namedmem->n_name));
325 				if (strcmp(m->s_name, namedmem->n_name) == 0) {
326 					cnt++;
327 					break;
328 				} else
329 					continue;
330 			}
331 			if (++cnt == 1) {
332 				istk->i_mem = m;
333 				istk->i_subt = m->s_type;
334 			}
335 		}
336 		if (namedmem != NULL) {
337 			istk->i_namedmem = 1;
338 			if (m == NULL) {
339 				error(101, namedmem->n_name);
340 				initerr = 1;
341 			} else {
342 				istk->i_mem = m;
343 				istk->i_subt = m->s_type;
344 			}
345 			memberpop();
346 			cnt = istk->i_type->t_tspec == STRUCT ? 2 : 1;
347 		}
348 		if (cnt == 0) {
349 			/* cannot init. struct/union with no named member */
350 			error(179);
351 			initerr = 1;
352 			return;
353 		}
354 		istk->i_cnt = istk->i_type->t_tspec == STRUCT ? cnt : 1;
355 		break;
356 	default:
357 		if (namedmem) {
358 			DPRINTF(("pushinit(): pop\n"));
359 			free(istk);
360 			initstk = initstk->i_nxt;
361 			goto again;
362 		}
363 		istk->i_cnt = 1;
364 		break;
365 	}
366 }
367 
368 static void
testinit(void)369 testinit(void)
370 {
371 	istk_t	*istk;
372 
373 	istk = initstk;
374 
375 	/*
376 	 * If a closing brace is expected we have at least one initializer
377 	 * too much.
378 	 */
379 	if (istk->i_cnt == 0 && !istk->i_nolimit && !istk->i_namedmem) {
380 		switch (istk->i_type->t_tspec) {
381 		case ARRAY:
382 			/* too many array initializers */
383 			error(173);
384 			break;
385 		case STRUCT:
386 		case UNION:
387 			/* too many struct/union initializers */
388 			error(172);
389 			break;
390 		default:
391 			/* too many initializers */
392 			error(174);
393 			break;
394 		}
395 		initerr = 1;
396 	}
397 }
398 
399 static void
nextinit(int brace)400 nextinit(int brace)
401 {
402 	char buf[64];
403 
404 	DPRINTF(("nextinit(%d)\n", brace));
405 	if (!brace) {
406 		if (initstk->i_type == NULL &&
407 		    !issclt(initstk->i_subt->t_tspec)) {
408 			/* {}-enclosed initializer required */
409 			error(181);
410 		}
411 		/*
412 		 * Make sure an entry with a scalar type is at the top
413 		 * of the stack.
414 		 */
415 		if (!initerr)
416 			testinit();
417 		while (!initerr && (initstk->i_type == NULL ||
418 				    !issclt(initstk->i_type->t_tspec))) {
419 			if (!initerr)
420 				pushinit();
421 		}
422 	} else {
423 		if (initstk->i_type != NULL &&
424 		    issclt(initstk->i_type->t_tspec)) {
425 			/* invalid initializer */
426 			error(176);
427 			initerr = 1;
428 		}
429 		if (!initerr)
430 			testinit();
431 		if (!initerr)
432 			pushinit();
433 		if (!initerr)
434 			initstk->i_brace = 1;
435 	}
436 }
437 
438 void
initlbr(void)439 initlbr(void)
440 {
441 
442 	if (initerr)
443 		return;
444 
445 	if ((initsym->s_scl == AUTO || initsym->s_scl == REG) &&
446 	    initstk->i_nxt == NULL) {
447 		if (tflag && !issclt(initstk->i_subt->t_tspec))
448 			/* no automatic aggregate initialization in trad. C*/
449 			warning(188);
450 	}
451 
452 	/*
453 	 * Remove all entries which cannot be used for further initializers
454 	 * and do not expect a closing brace.
455 	 */
456 	popinit(0);
457 
458 	nextinit(1);
459 }
460 
461 void
initrbr(void)462 initrbr(void)
463 {
464 
465 	if (initerr)
466 		return;
467 
468 	popinit(1);
469 }
470 
471 void
mkinit(tnode_t * tn)472 mkinit(tnode_t *tn)
473 {
474 	ptrdiff_t offs;
475 	sym_t	*sym;
476 	tspec_t	lt, rt;
477 	tnode_t	*ln;
478 	struct	mbl *tmem;
479 	scl_t	sc;
480 #ifdef DEBUG
481 	char	buf[64];
482 #endif
483 
484 	DPRINTF(("mkinit(%s)\n", tyname(buf, sizeof(buf), tn->tn_type)));
485 	if (initerr || tn == NULL)
486 		goto end;
487 
488 	sc = initsym->s_scl;
489 
490 	/*
491 	 * Do not test for automatic aggregate initialisation. If the
492 	 * initializer starts with a brace we have the warning already.
493 	 * If not, an error will be printed that the initializer must
494 	 * be enclosed by braces.
495 	 */
496 
497 	/*
498 	 * Local initialisation of non-array-types with only one expression
499 	 * without braces is done by ASSIGN
500 	 */
501 	if ((sc == AUTO || sc == REG) &&
502 	    initsym->s_type->t_tspec != ARRAY && initstk->i_nxt == NULL) {
503 		ln = getnnode(initsym, 0);
504 		ln->tn_type = tduptyp(ln->tn_type);
505 		ln->tn_type->t_const = 0;
506 		tn = build(ASSIGN, ln, tn);
507 		expr(tn, 0, 0, 1);
508 		goto end;
509 	}
510 
511 	/*
512 	 * Remove all entries which cannot be used for further initializers
513 	 * and do not require a closing brace.
514 	 */
515 	popinit(0);
516 
517 	/* Initialisations by strings are done in strginit(). */
518 	if (strginit(tn))
519 		goto end;
520 
521 	nextinit(0);
522 	if (initerr || tn == NULL)
523 		goto end;
524 
525 	initstk->i_cnt--;
526 	DPRINTF(("mkinit() cnt=%d tn=%p\n", initstk->i_cnt, tn));
527 	/* Create a temporary node for the left side. */
528 	ln = tgetblk(sizeof (tnode_t));
529 	ln->tn_op = NAME;
530 	ln->tn_type = tduptyp(initstk->i_type);
531 	ln->tn_type->t_const = 0;
532 	ln->tn_lvalue = 1;
533 	ln->tn_sym = initsym;		/* better than nothing */
534 
535 	tn = cconv(tn);
536 
537 	lt = ln->tn_type->t_tspec;
538 	rt = tn->tn_type->t_tspec;
539 
540 	if (!issclt(lt))
541 		LERROR("mkinit()");
542 
543 	if (!typeok(INIT, 0, ln, tn))
544 		goto end;
545 
546 	/*
547 	 * Store the tree memory. This is necessary because otherwise
548 	 * expr() would free it.
549 	 */
550 	tmem = tsave();
551 	expr(tn, 1, 0, 1);
552 	trestor(tmem);
553 
554 	if (isityp(lt) && ln->tn_type->t_isfield && !isityp(rt)) {
555 		/*
556 		 * Bit-fields can be initialized in trad. C only by integer
557 		 * constants.
558 		 */
559 		if (tflag)
560 			/* bit-field initialisation is illegal in trad. C */
561 			warning(186);
562 	}
563 
564 	if (lt != rt || (initstk->i_type->t_isfield && tn->tn_op == CON))
565 		tn = convert(INIT, 0, initstk->i_type, tn);
566 
567 	if (tn != NULL && tn->tn_op != CON) {
568 		sym = NULL;
569 		offs = 0;
570 		if (conaddr(tn, &sym, &offs) == -1) {
571 			if (sc == AUTO || sc == REG) {
572 				/* non-constant initializer */
573 				(void)gnuism(177);
574 			} else {
575 				/* non-constant initializer */
576 				error(177);
577 			}
578 		}
579 	}
580 
581  end:
582 	/*
583 	 * We only free the block, if we are not a compound declaration
584 	 * We know that the only symbols that start with a digit are the
585 	 * ones we allocate with mktempsym() for compound declarations
586 	 */
587 	if (!isdigit((unsigned char)initsym->s_name[0]))
588 		tfreeblk();
589 }
590 
591 
592 static int
strginit(tnode_t * tn)593 strginit(tnode_t *tn)
594 {
595 	tspec_t	t;
596 	istk_t	*istk;
597 	int	len;
598 	strg_t	*strg;
599 
600 	if (tn->tn_op != STRING)
601 		return (0);
602 
603 	istk = initstk;
604 	strg = tn->tn_strg;
605 
606 	/*
607 	 * Check if we have an array type which can be initialized by
608 	 * the string.
609 	 */
610 	if (istk->i_subt != NULL && istk->i_subt->t_tspec == ARRAY) {
611 		t = istk->i_subt->t_subt->t_tspec;
612 		if (!((strg->st_tspec == CHAR &&
613 		       (t == CHAR || t == UCHAR || t == SCHAR)) ||
614 		      (strg->st_tspec == WCHAR && t == WCHAR))) {
615 			return (0);
616 		}
617 		/* Put the array at top of stack */
618 		pushinit();
619 		istk = initstk;
620 	} else if (istk->i_type != NULL && istk->i_type->t_tspec == ARRAY) {
621 		t = istk->i_type->t_subt->t_tspec;
622 		if (!((strg->st_tspec == CHAR &&
623 		       (t == CHAR || t == UCHAR || t == SCHAR)) ||
624 		      (strg->st_tspec == WCHAR && t == WCHAR))) {
625 			return (0);
626 		}
627 		/*
628 		 * If the array is already partly initialized, we are
629 		 * wrong here.
630 		 */
631 		if (istk->i_cnt != istk->i_type->t_dim)
632 			return (0);
633 	} else {
634 		return (0);
635 	}
636 
637 	/* Get length without trailing NUL character. */
638 	len = strg->st_len;
639 
640 	if (istk->i_nolimit) {
641 		istk->i_nolimit = 0;
642 		istk->i_type->t_dim = len + 1;
643 		/* from now complete type */
644 		setcompl(istk->i_type, 0);
645 	} else {
646 		if (istk->i_type->t_dim < len) {
647 			/* non-null byte ignored in string initializer */
648 			warning(187);
649 		}
650 	}
651 
652 	/* In every case the array is initialized completely. */
653 	istk->i_cnt = 0;
654 
655 	return (1);
656 }
657