xref: /openbmc/linux/scripts/kconfig/symbol.c (revision 060f35a317ef09101b128f399dce7ed13d019461)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
4  */
5 
6 #include <sys/types.h>
7 #include <ctype.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <regex.h>
11 
12 #include "lkc.h"
13 
14 struct symbol symbol_yes = {
15 	.name = "y",
16 	.type = S_TRISTATE,
17 	.curr = { "y", yes },
18 	.flags = SYMBOL_CONST|SYMBOL_VALID,
19 };
20 
21 struct symbol symbol_mod = {
22 	.name = "m",
23 	.type = S_TRISTATE,
24 	.curr = { "m", mod },
25 	.flags = SYMBOL_CONST|SYMBOL_VALID,
26 };
27 
28 struct symbol symbol_no = {
29 	.name = "n",
30 	.type = S_TRISTATE,
31 	.curr = { "n", no },
32 	.flags = SYMBOL_CONST|SYMBOL_VALID,
33 };
34 
35 static struct symbol symbol_empty = {
36 	.name = "",
37 	.curr = { "", no },
38 	.flags = SYMBOL_VALID,
39 };
40 
41 struct symbol *modules_sym;
42 static tristate modules_val;
43 static int sym_warnings;
44 
sym_get_type(struct symbol * sym)45 enum symbol_type sym_get_type(struct symbol *sym)
46 {
47 	enum symbol_type type = sym->type;
48 
49 	if (type == S_TRISTATE) {
50 		if (sym_is_choice_value(sym) && sym->visible == yes)
51 			type = S_BOOLEAN;
52 		else if (modules_val == no)
53 			type = S_BOOLEAN;
54 	}
55 	return type;
56 }
57 
sym_type_name(enum symbol_type type)58 const char *sym_type_name(enum symbol_type type)
59 {
60 	switch (type) {
61 	case S_BOOLEAN:
62 		return "bool";
63 	case S_TRISTATE:
64 		return "tristate";
65 	case S_INT:
66 		return "integer";
67 	case S_HEX:
68 		return "hex";
69 	case S_STRING:
70 		return "string";
71 	case S_UNKNOWN:
72 		return "unknown";
73 	}
74 	return "???";
75 }
76 
sym_get_choice_prop(struct symbol * sym)77 struct property *sym_get_choice_prop(struct symbol *sym)
78 {
79 	struct property *prop;
80 
81 	for_all_choices(sym, prop)
82 		return prop;
83 	return NULL;
84 }
85 
sym_get_default_prop(struct symbol * sym)86 static struct property *sym_get_default_prop(struct symbol *sym)
87 {
88 	struct property *prop;
89 
90 	for_all_defaults(sym, prop) {
91 		prop->visible.tri = expr_calc_value(prop->visible.expr);
92 		if (prop->visible.tri != no)
93 			return prop;
94 	}
95 	return NULL;
96 }
97 
sym_get_range_prop(struct symbol * sym)98 struct property *sym_get_range_prop(struct symbol *sym)
99 {
100 	struct property *prop;
101 
102 	for_all_properties(sym, prop, P_RANGE) {
103 		prop->visible.tri = expr_calc_value(prop->visible.expr);
104 		if (prop->visible.tri != no)
105 			return prop;
106 	}
107 	return NULL;
108 }
109 
sym_get_range_val(struct symbol * sym,int base)110 static long long sym_get_range_val(struct symbol *sym, int base)
111 {
112 	sym_calc_value(sym);
113 	switch (sym->type) {
114 	case S_INT:
115 		base = 10;
116 		break;
117 	case S_HEX:
118 		base = 16;
119 		break;
120 	default:
121 		break;
122 	}
123 	return strtoll(sym->curr.val, NULL, base);
124 }
125 
sym_validate_range(struct symbol * sym)126 static void sym_validate_range(struct symbol *sym)
127 {
128 	struct property *prop;
129 	struct symbol *range_sym;
130 	int base;
131 	long long val, val2;
132 
133 	switch (sym->type) {
134 	case S_INT:
135 		base = 10;
136 		break;
137 	case S_HEX:
138 		base = 16;
139 		break;
140 	default:
141 		return;
142 	}
143 	prop = sym_get_range_prop(sym);
144 	if (!prop)
145 		return;
146 	val = strtoll(sym->curr.val, NULL, base);
147 	range_sym = prop->expr->left.sym;
148 	val2 = sym_get_range_val(range_sym, base);
149 	if (val >= val2) {
150 		range_sym = prop->expr->right.sym;
151 		val2 = sym_get_range_val(range_sym, base);
152 		if (val <= val2)
153 			return;
154 	}
155 	sym->curr.val = range_sym->curr.val;
156 }
157 
sym_set_changed(struct symbol * sym)158 static void sym_set_changed(struct symbol *sym)
159 {
160 	struct property *prop;
161 
162 	sym->flags |= SYMBOL_CHANGED;
163 	for (prop = sym->prop; prop; prop = prop->next) {
164 		if (prop->menu)
165 			prop->menu->flags |= MENU_CHANGED;
166 	}
167 }
168 
sym_set_all_changed(void)169 static void sym_set_all_changed(void)
170 {
171 	struct symbol *sym;
172 	int i;
173 
174 	for_all_symbols(i, sym)
175 		sym_set_changed(sym);
176 }
177 
sym_calc_visibility(struct symbol * sym)178 static void sym_calc_visibility(struct symbol *sym)
179 {
180 	struct property *prop;
181 	struct symbol *choice_sym = NULL;
182 	tristate tri;
183 
184 	/* any prompt visible? */
185 	tri = no;
186 
187 	if (sym_is_choice_value(sym))
188 		choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
189 
190 	for_all_prompts(sym, prop) {
191 		prop->visible.tri = expr_calc_value(prop->visible.expr);
192 		/*
193 		 * Tristate choice_values with visibility 'mod' are
194 		 * not visible if the corresponding choice's value is
195 		 * 'yes'.
196 		 */
197 		if (choice_sym && sym->type == S_TRISTATE &&
198 		    prop->visible.tri == mod && choice_sym->curr.tri == yes)
199 			prop->visible.tri = no;
200 
201 		tri = EXPR_OR(tri, prop->visible.tri);
202 	}
203 	if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
204 		tri = yes;
205 	if (sym->visible != tri) {
206 		sym->visible = tri;
207 		sym_set_changed(sym);
208 	}
209 	if (sym_is_choice_value(sym))
210 		return;
211 	/* defaulting to "yes" if no explicit "depends on" are given */
212 	tri = yes;
213 	if (sym->dir_dep.expr)
214 		tri = expr_calc_value(sym->dir_dep.expr);
215 	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
216 		tri = yes;
217 	if (sym->dir_dep.tri != tri) {
218 		sym->dir_dep.tri = tri;
219 		sym_set_changed(sym);
220 	}
221 	tri = no;
222 	if (sym->rev_dep.expr)
223 		tri = expr_calc_value(sym->rev_dep.expr);
224 	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
225 		tri = yes;
226 	if (sym->rev_dep.tri != tri) {
227 		sym->rev_dep.tri = tri;
228 		sym_set_changed(sym);
229 	}
230 	tri = no;
231 	if (sym->implied.expr)
232 		tri = expr_calc_value(sym->implied.expr);
233 	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
234 		tri = yes;
235 	if (sym->implied.tri != tri) {
236 		sym->implied.tri = tri;
237 		sym_set_changed(sym);
238 	}
239 }
240 
241 /*
242  * Find the default symbol for a choice.
243  * First try the default values for the choice symbol
244  * Next locate the first visible choice value
245  * Return NULL if none was found
246  */
sym_choice_default(struct symbol * sym)247 struct symbol *sym_choice_default(struct symbol *sym)
248 {
249 	struct symbol *def_sym;
250 	struct property *prop;
251 	struct expr *e;
252 
253 	/* any of the defaults visible? */
254 	for_all_defaults(sym, prop) {
255 		prop->visible.tri = expr_calc_value(prop->visible.expr);
256 		if (prop->visible.tri == no)
257 			continue;
258 		def_sym = prop_get_symbol(prop);
259 		if (def_sym->visible != no)
260 			return def_sym;
261 	}
262 
263 	/* just get the first visible value */
264 	prop = sym_get_choice_prop(sym);
265 	expr_list_for_each_sym(prop->expr, e, def_sym)
266 		if (def_sym->visible != no)
267 			return def_sym;
268 
269 	/* failed to locate any defaults */
270 	return NULL;
271 }
272 
sym_calc_choice(struct symbol * sym)273 static struct symbol *sym_calc_choice(struct symbol *sym)
274 {
275 	struct symbol *def_sym;
276 	struct property *prop;
277 	struct expr *e;
278 	int flags;
279 
280 	/* first calculate all choice values' visibilities */
281 	flags = sym->flags;
282 	prop = sym_get_choice_prop(sym);
283 	expr_list_for_each_sym(prop->expr, e, def_sym) {
284 		sym_calc_visibility(def_sym);
285 		if (def_sym->visible != no)
286 			flags &= def_sym->flags;
287 	}
288 
289 	sym->flags &= flags | ~SYMBOL_DEF_USER;
290 
291 	/* is the user choice visible? */
292 	def_sym = sym->def[S_DEF_USER].val;
293 	if (def_sym && def_sym->visible != no)
294 		return def_sym;
295 
296 	def_sym = sym_choice_default(sym);
297 
298 	if (def_sym == NULL)
299 		/* no choice? reset tristate value */
300 		sym->curr.tri = no;
301 
302 	return def_sym;
303 }
304 
sym_warn_unmet_dep(struct symbol * sym)305 static void sym_warn_unmet_dep(struct symbol *sym)
306 {
307 	struct gstr gs = str_new();
308 
309 	str_printf(&gs,
310 		   "\nWARNING: unmet direct dependencies detected for %s\n",
311 		   sym->name);
312 	str_printf(&gs,
313 		   "  Depends on [%c]: ",
314 		   sym->dir_dep.tri == mod ? 'm' : 'n');
315 	expr_gstr_print(sym->dir_dep.expr, &gs);
316 	str_printf(&gs, "\n");
317 
318 	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
319 			       "  Selected by [y]:\n");
320 	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
321 			       "  Selected by [m]:\n");
322 
323 	fputs(str_get(&gs), stderr);
324 	str_free(&gs);
325 	sym_warnings++;
326 }
327 
sym_dep_errors(void)328 bool sym_dep_errors(void)
329 {
330 	if (sym_warnings)
331 		return getenv("KCONFIG_WERROR");
332 	return false;
333 }
334 
sym_calc_value(struct symbol * sym)335 void sym_calc_value(struct symbol *sym)
336 {
337 	struct symbol_value newval, oldval;
338 	struct property *prop;
339 	struct expr *e;
340 
341 	if (!sym)
342 		return;
343 
344 	if (sym->flags & SYMBOL_VALID)
345 		return;
346 
347 	if (sym_is_choice_value(sym) &&
348 	    sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
349 		sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
350 		prop = sym_get_choice_prop(sym);
351 		sym_calc_value(prop_get_symbol(prop));
352 	}
353 
354 	sym->flags |= SYMBOL_VALID;
355 
356 	oldval = sym->curr;
357 
358 	switch (sym->type) {
359 	case S_INT:
360 	case S_HEX:
361 	case S_STRING:
362 		newval = symbol_empty.curr;
363 		break;
364 	case S_BOOLEAN:
365 	case S_TRISTATE:
366 		newval = symbol_no.curr;
367 		break;
368 	default:
369 		sym->curr.val = sym->name;
370 		sym->curr.tri = no;
371 		return;
372 	}
373 	sym->flags &= ~SYMBOL_WRITE;
374 
375 	sym_calc_visibility(sym);
376 
377 	if (sym->visible != no)
378 		sym->flags |= SYMBOL_WRITE;
379 
380 	/* set default if recursively called */
381 	sym->curr = newval;
382 
383 	switch (sym_get_type(sym)) {
384 	case S_BOOLEAN:
385 	case S_TRISTATE:
386 		if (sym_is_choice_value(sym) && sym->visible == yes) {
387 			prop = sym_get_choice_prop(sym);
388 			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
389 		} else {
390 			if (sym->visible != no) {
391 				/* if the symbol is visible use the user value
392 				 * if available, otherwise try the default value
393 				 */
394 				if (sym_has_value(sym)) {
395 					newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
396 							      sym->visible);
397 					goto calc_newval;
398 				}
399 			}
400 			if (sym->rev_dep.tri != no)
401 				sym->flags |= SYMBOL_WRITE;
402 			if (!sym_is_choice(sym)) {
403 				prop = sym_get_default_prop(sym);
404 				if (prop) {
405 					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
406 							      prop->visible.tri);
407 					if (newval.tri != no)
408 						sym->flags |= SYMBOL_WRITE;
409 				}
410 				if (sym->implied.tri != no) {
411 					sym->flags |= SYMBOL_WRITE;
412 					newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
413 					newval.tri = EXPR_AND(newval.tri,
414 							      sym->dir_dep.tri);
415 				}
416 			}
417 		calc_newval:
418 			if (sym->dir_dep.tri < sym->rev_dep.tri)
419 				sym_warn_unmet_dep(sym);
420 			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
421 		}
422 		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
423 			newval.tri = yes;
424 		break;
425 	case S_STRING:
426 	case S_HEX:
427 	case S_INT:
428 		if (sym->visible != no && sym_has_value(sym)) {
429 			newval.val = sym->def[S_DEF_USER].val;
430 			break;
431 		}
432 		prop = sym_get_default_prop(sym);
433 		if (prop) {
434 			struct symbol *ds = prop_get_symbol(prop);
435 			if (ds) {
436 				sym->flags |= SYMBOL_WRITE;
437 				sym_calc_value(ds);
438 				newval.val = ds->curr.val;
439 			}
440 		}
441 		break;
442 	default:
443 		;
444 	}
445 
446 	sym->curr = newval;
447 	if (sym_is_choice(sym) && newval.tri == yes)
448 		sym->curr.val = sym_calc_choice(sym);
449 	sym_validate_range(sym);
450 
451 	if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
452 		sym_set_changed(sym);
453 		if (modules_sym == sym) {
454 			sym_set_all_changed();
455 			modules_val = modules_sym->curr.tri;
456 		}
457 	}
458 
459 	if (sym_is_choice(sym)) {
460 		struct symbol *choice_sym;
461 
462 		prop = sym_get_choice_prop(sym);
463 		expr_list_for_each_sym(prop->expr, e, choice_sym) {
464 			if ((sym->flags & SYMBOL_WRITE) &&
465 			    choice_sym->visible != no)
466 				choice_sym->flags |= SYMBOL_WRITE;
467 			if (sym->flags & SYMBOL_CHANGED)
468 				sym_set_changed(choice_sym);
469 		}
470 	}
471 
472 	if (sym->flags & SYMBOL_NO_WRITE)
473 		sym->flags &= ~SYMBOL_WRITE;
474 
475 	if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
476 		set_all_choice_values(sym);
477 }
478 
sym_clear_all_valid(void)479 void sym_clear_all_valid(void)
480 {
481 	struct symbol *sym;
482 	int i;
483 
484 	for_all_symbols(i, sym)
485 		sym->flags &= ~SYMBOL_VALID;
486 	conf_set_changed(true);
487 	sym_calc_value(modules_sym);
488 }
489 
sym_tristate_within_range(struct symbol * sym,tristate val)490 bool sym_tristate_within_range(struct symbol *sym, tristate val)
491 {
492 	int type = sym_get_type(sym);
493 
494 	if (sym->visible == no)
495 		return false;
496 
497 	if (type != S_BOOLEAN && type != S_TRISTATE)
498 		return false;
499 
500 	if (type == S_BOOLEAN && val == mod)
501 		return false;
502 	if (sym->visible <= sym->rev_dep.tri)
503 		return false;
504 	if (sym_is_choice_value(sym) && sym->visible == yes)
505 		return val == yes;
506 	return val >= sym->rev_dep.tri && val <= sym->visible;
507 }
508 
sym_set_tristate_value(struct symbol * sym,tristate val)509 bool sym_set_tristate_value(struct symbol *sym, tristate val)
510 {
511 	tristate oldval = sym_get_tristate_value(sym);
512 
513 	if (oldval != val && !sym_tristate_within_range(sym, val))
514 		return false;
515 
516 	if (!(sym->flags & SYMBOL_DEF_USER)) {
517 		sym->flags |= SYMBOL_DEF_USER;
518 		sym_set_changed(sym);
519 	}
520 	/*
521 	 * setting a choice value also resets the new flag of the choice
522 	 * symbol and all other choice values.
523 	 */
524 	if (sym_is_choice_value(sym) && val == yes) {
525 		struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
526 		struct property *prop;
527 		struct expr *e;
528 
529 		cs->def[S_DEF_USER].val = sym;
530 		cs->flags |= SYMBOL_DEF_USER;
531 		prop = sym_get_choice_prop(cs);
532 		for (e = prop->expr; e; e = e->left.expr) {
533 			if (e->right.sym->visible != no)
534 				e->right.sym->flags |= SYMBOL_DEF_USER;
535 		}
536 	}
537 
538 	sym->def[S_DEF_USER].tri = val;
539 	if (oldval != val)
540 		sym_clear_all_valid();
541 
542 	return true;
543 }
544 
sym_toggle_tristate_value(struct symbol * sym)545 tristate sym_toggle_tristate_value(struct symbol *sym)
546 {
547 	tristate oldval, newval;
548 
549 	oldval = newval = sym_get_tristate_value(sym);
550 	do {
551 		switch (newval) {
552 		case no:
553 			newval = mod;
554 			break;
555 		case mod:
556 			newval = yes;
557 			break;
558 		case yes:
559 			newval = no;
560 			break;
561 		}
562 		if (sym_set_tristate_value(sym, newval))
563 			break;
564 	} while (oldval != newval);
565 	return newval;
566 }
567 
sym_string_valid(struct symbol * sym,const char * str)568 bool sym_string_valid(struct symbol *sym, const char *str)
569 {
570 	signed char ch;
571 
572 	switch (sym->type) {
573 	case S_STRING:
574 		return true;
575 	case S_INT:
576 		ch = *str++;
577 		if (ch == '-')
578 			ch = *str++;
579 		if (!isdigit(ch))
580 			return false;
581 		if (ch == '0' && *str != 0)
582 			return false;
583 		while ((ch = *str++)) {
584 			if (!isdigit(ch))
585 				return false;
586 		}
587 		return true;
588 	case S_HEX:
589 		if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
590 			str += 2;
591 		ch = *str++;
592 		do {
593 			if (!isxdigit(ch))
594 				return false;
595 		} while ((ch = *str++));
596 		return true;
597 	case S_BOOLEAN:
598 	case S_TRISTATE:
599 		switch (str[0]) {
600 		case 'y': case 'Y':
601 		case 'm': case 'M':
602 		case 'n': case 'N':
603 			return true;
604 		}
605 		return false;
606 	default:
607 		return false;
608 	}
609 }
610 
sym_string_within_range(struct symbol * sym,const char * str)611 bool sym_string_within_range(struct symbol *sym, const char *str)
612 {
613 	struct property *prop;
614 	long long val;
615 
616 	switch (sym->type) {
617 	case S_STRING:
618 		return sym_string_valid(sym, str);
619 	case S_INT:
620 		if (!sym_string_valid(sym, str))
621 			return false;
622 		prop = sym_get_range_prop(sym);
623 		if (!prop)
624 			return true;
625 		val = strtoll(str, NULL, 10);
626 		return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
627 		       val <= sym_get_range_val(prop->expr->right.sym, 10);
628 	case S_HEX:
629 		if (!sym_string_valid(sym, str))
630 			return false;
631 		prop = sym_get_range_prop(sym);
632 		if (!prop)
633 			return true;
634 		val = strtoll(str, NULL, 16);
635 		return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
636 		       val <= sym_get_range_val(prop->expr->right.sym, 16);
637 	case S_BOOLEAN:
638 	case S_TRISTATE:
639 		switch (str[0]) {
640 		case 'y': case 'Y':
641 			return sym_tristate_within_range(sym, yes);
642 		case 'm': case 'M':
643 			return sym_tristate_within_range(sym, mod);
644 		case 'n': case 'N':
645 			return sym_tristate_within_range(sym, no);
646 		}
647 		return false;
648 	default:
649 		return false;
650 	}
651 }
652 
sym_set_string_value(struct symbol * sym,const char * newval)653 bool sym_set_string_value(struct symbol *sym, const char *newval)
654 {
655 	const char *oldval;
656 	char *val;
657 	int size;
658 
659 	switch (sym->type) {
660 	case S_BOOLEAN:
661 	case S_TRISTATE:
662 		switch (newval[0]) {
663 		case 'y': case 'Y':
664 			return sym_set_tristate_value(sym, yes);
665 		case 'm': case 'M':
666 			return sym_set_tristate_value(sym, mod);
667 		case 'n': case 'N':
668 			return sym_set_tristate_value(sym, no);
669 		}
670 		return false;
671 	default:
672 		;
673 	}
674 
675 	if (!sym_string_within_range(sym, newval))
676 		return false;
677 
678 	if (!(sym->flags & SYMBOL_DEF_USER)) {
679 		sym->flags |= SYMBOL_DEF_USER;
680 		sym_set_changed(sym);
681 	}
682 
683 	oldval = sym->def[S_DEF_USER].val;
684 	size = strlen(newval) + 1;
685 	if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
686 		size += 2;
687 		sym->def[S_DEF_USER].val = val = xmalloc(size);
688 		*val++ = '0';
689 		*val++ = 'x';
690 	} else if (!oldval || strcmp(oldval, newval))
691 		sym->def[S_DEF_USER].val = val = xmalloc(size);
692 	else
693 		return true;
694 
695 	strcpy(val, newval);
696 	free((void *)oldval);
697 	sym_clear_all_valid();
698 
699 	return true;
700 }
701 
702 /*
703  * Find the default value associated to a symbol.
704  * For tristate symbol handle the modules=n case
705  * in which case "m" becomes "y".
706  * If the symbol does not have any default then fallback
707  * to the fixed default values.
708  */
sym_get_string_default(struct symbol * sym)709 const char *sym_get_string_default(struct symbol *sym)
710 {
711 	struct property *prop;
712 	struct symbol *ds;
713 	const char *str;
714 	tristate val;
715 
716 	sym_calc_visibility(sym);
717 	sym_calc_value(modules_sym);
718 	val = symbol_no.curr.tri;
719 	str = symbol_empty.curr.val;
720 
721 	/* If symbol has a default value look it up */
722 	prop = sym_get_default_prop(sym);
723 	if (prop != NULL) {
724 		switch (sym->type) {
725 		case S_BOOLEAN:
726 		case S_TRISTATE:
727 			/* The visibility may limit the value from yes => mod */
728 			val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
729 			break;
730 		default:
731 			/*
732 			 * The following fails to handle the situation
733 			 * where a default value is further limited by
734 			 * the valid range.
735 			 */
736 			ds = prop_get_symbol(prop);
737 			if (ds != NULL) {
738 				sym_calc_value(ds);
739 				str = (const char *)ds->curr.val;
740 			}
741 		}
742 	}
743 
744 	/* Handle select statements */
745 	val = EXPR_OR(val, sym->rev_dep.tri);
746 
747 	/* transpose mod to yes if modules are not enabled */
748 	if (val == mod)
749 		if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
750 			val = yes;
751 
752 	/* transpose mod to yes if type is bool */
753 	if (sym->type == S_BOOLEAN && val == mod)
754 		val = yes;
755 
756 	/* adjust the default value if this symbol is implied by another */
757 	if (val < sym->implied.tri)
758 		val = sym->implied.tri;
759 
760 	switch (sym->type) {
761 	case S_BOOLEAN:
762 	case S_TRISTATE:
763 		switch (val) {
764 		case no: return "n";
765 		case mod: return "m";
766 		case yes: return "y";
767 		}
768 	case S_INT:
769 	case S_HEX:
770 		return str;
771 	case S_STRING:
772 		return str;
773 	case S_UNKNOWN:
774 		break;
775 	}
776 	return "";
777 }
778 
sym_get_string_value(struct symbol * sym)779 const char *sym_get_string_value(struct symbol *sym)
780 {
781 	tristate val;
782 
783 	switch (sym->type) {
784 	case S_BOOLEAN:
785 	case S_TRISTATE:
786 		val = sym_get_tristate_value(sym);
787 		switch (val) {
788 		case no:
789 			return "n";
790 		case mod:
791 			return "m";
792 		case yes:
793 			return "y";
794 		}
795 		break;
796 	default:
797 		;
798 	}
799 	return (const char *)sym->curr.val;
800 }
801 
sym_is_changeable(struct symbol * sym)802 bool sym_is_changeable(struct symbol *sym)
803 {
804 	return sym->visible > sym->rev_dep.tri;
805 }
806 
strhash(const char * s)807 static unsigned strhash(const char *s)
808 {
809 	/* fnv32 hash */
810 	unsigned hash = 2166136261U;
811 	for (; *s; s++)
812 		hash = (hash ^ *s) * 0x01000193;
813 	return hash;
814 }
815 
sym_lookup(const char * name,int flags)816 struct symbol *sym_lookup(const char *name, int flags)
817 {
818 	struct symbol *symbol;
819 	char *new_name;
820 	int hash;
821 
822 	if (name) {
823 		if (name[0] && !name[1]) {
824 			switch (name[0]) {
825 			case 'y': return &symbol_yes;
826 			case 'm': return &symbol_mod;
827 			case 'n': return &symbol_no;
828 			}
829 		}
830 		hash = strhash(name) % SYMBOL_HASHSIZE;
831 
832 		for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
833 			if (symbol->name &&
834 			    !strcmp(symbol->name, name) &&
835 			    (flags ? symbol->flags & flags
836 				   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
837 				return symbol;
838 		}
839 		new_name = xstrdup(name);
840 	} else {
841 		new_name = NULL;
842 		hash = 0;
843 	}
844 
845 	symbol = xmalloc(sizeof(*symbol));
846 	memset(symbol, 0, sizeof(*symbol));
847 	symbol->name = new_name;
848 	symbol->type = S_UNKNOWN;
849 	symbol->flags = flags;
850 
851 	symbol->next = symbol_hash[hash];
852 	symbol_hash[hash] = symbol;
853 
854 	return symbol;
855 }
856 
sym_find(const char * name)857 struct symbol *sym_find(const char *name)
858 {
859 	struct symbol *symbol = NULL;
860 	int hash = 0;
861 
862 	if (!name)
863 		return NULL;
864 
865 	if (name[0] && !name[1]) {
866 		switch (name[0]) {
867 		case 'y': return &symbol_yes;
868 		case 'm': return &symbol_mod;
869 		case 'n': return &symbol_no;
870 		}
871 	}
872 	hash = strhash(name) % SYMBOL_HASHSIZE;
873 
874 	for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
875 		if (symbol->name &&
876 		    !strcmp(symbol->name, name) &&
877 		    !(symbol->flags & SYMBOL_CONST))
878 				break;
879 	}
880 
881 	return symbol;
882 }
883 
884 struct sym_match {
885 	struct symbol	*sym;
886 	off_t		so, eo;
887 };
888 
889 /* Compare matched symbols as thus:
890  * - first, symbols that match exactly
891  * - then, alphabetical sort
892  */
sym_rel_comp(const void * sym1,const void * sym2)893 static int sym_rel_comp(const void *sym1, const void *sym2)
894 {
895 	const struct sym_match *s1 = sym1;
896 	const struct sym_match *s2 = sym2;
897 	int exact1, exact2;
898 
899 	/* Exact match:
900 	 * - if matched length on symbol s1 is the length of that symbol,
901 	 *   then this symbol should come first;
902 	 * - if matched length on symbol s2 is the length of that symbol,
903 	 *   then this symbol should come first.
904 	 * Note: since the search can be a regexp, both symbols may match
905 	 * exactly; if this is the case, we can't decide which comes first,
906 	 * and we fallback to sorting alphabetically.
907 	 */
908 	exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
909 	exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
910 	if (exact1 && !exact2)
911 		return -1;
912 	if (!exact1 && exact2)
913 		return 1;
914 
915 	/* As a fallback, sort symbols alphabetically */
916 	return strcmp(s1->sym->name, s2->sym->name);
917 }
918 
sym_re_search(const char * pattern)919 struct symbol **sym_re_search(const char *pattern)
920 {
921 	struct symbol *sym, **sym_arr = NULL;
922 	struct sym_match *sym_match_arr = NULL;
923 	int i, cnt, size;
924 	regex_t re;
925 	regmatch_t match[1];
926 
927 	cnt = size = 0;
928 	/* Skip if empty */
929 	if (strlen(pattern) == 0)
930 		return NULL;
931 	if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
932 		return NULL;
933 
934 	for_all_symbols(i, sym) {
935 		if (sym->flags & SYMBOL_CONST || !sym->name)
936 			continue;
937 		if (regexec(&re, sym->name, 1, match, 0))
938 			continue;
939 		if (cnt >= size) {
940 			void *tmp;
941 			size += 16;
942 			tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
943 			if (!tmp)
944 				goto sym_re_search_free;
945 			sym_match_arr = tmp;
946 		}
947 		sym_calc_value(sym);
948 		/* As regexec returned 0, we know we have a match, so
949 		 * we can use match[0].rm_[se]o without further checks
950 		 */
951 		sym_match_arr[cnt].so = match[0].rm_so;
952 		sym_match_arr[cnt].eo = match[0].rm_eo;
953 		sym_match_arr[cnt++].sym = sym;
954 	}
955 	if (sym_match_arr) {
956 		qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
957 		sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
958 		if (!sym_arr)
959 			goto sym_re_search_free;
960 		for (i = 0; i < cnt; i++)
961 			sym_arr[i] = sym_match_arr[i].sym;
962 		sym_arr[cnt] = NULL;
963 	}
964 sym_re_search_free:
965 	/* sym_match_arr can be NULL if no match, but free(NULL) is OK */
966 	free(sym_match_arr);
967 	regfree(&re);
968 
969 	return sym_arr;
970 }
971 
972 /*
973  * When we check for recursive dependencies we use a stack to save
974  * current state so we can print out relevant info to user.
975  * The entries are located on the call stack so no need to free memory.
976  * Note insert() remove() must always match to properly clear the stack.
977  */
978 static struct dep_stack {
979 	struct dep_stack *prev, *next;
980 	struct symbol *sym;
981 	struct property *prop;
982 	struct expr **expr;
983 } *check_top;
984 
dep_stack_insert(struct dep_stack * stack,struct symbol * sym)985 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
986 {
987 	memset(stack, 0, sizeof(*stack));
988 	if (check_top)
989 		check_top->next = stack;
990 	stack->prev = check_top;
991 	stack->sym = sym;
992 	check_top = stack;
993 }
994 
dep_stack_remove(void)995 static void dep_stack_remove(void)
996 {
997 	check_top = check_top->prev;
998 	if (check_top)
999 		check_top->next = NULL;
1000 }
1001 
1002 /*
1003  * Called when we have detected a recursive dependency.
1004  * check_top point to the top of the stact so we use
1005  * the ->prev pointer to locate the bottom of the stack.
1006  */
sym_check_print_recursive(struct symbol * last_sym)1007 static void sym_check_print_recursive(struct symbol *last_sym)
1008 {
1009 	struct dep_stack *stack;
1010 	struct symbol *sym, *next_sym;
1011 	struct menu *menu = NULL;
1012 	struct property *prop;
1013 	struct dep_stack cv_stack;
1014 
1015 	if (sym_is_choice_value(last_sym)) {
1016 		dep_stack_insert(&cv_stack, last_sym);
1017 		last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1018 	}
1019 
1020 	for (stack = check_top; stack != NULL; stack = stack->prev)
1021 		if (stack->sym == last_sym)
1022 			break;
1023 	if (!stack) {
1024 		fprintf(stderr, "unexpected recursive dependency error\n");
1025 		return;
1026 	}
1027 
1028 	for (; stack; stack = stack->next) {
1029 		sym = stack->sym;
1030 		next_sym = stack->next ? stack->next->sym : last_sym;
1031 		prop = stack->prop;
1032 		if (prop == NULL)
1033 			prop = stack->sym->prop;
1034 
1035 		/* for choice values find the menu entry (used below) */
1036 		if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1037 			for (prop = sym->prop; prop; prop = prop->next) {
1038 				menu = prop->menu;
1039 				if (prop->menu)
1040 					break;
1041 			}
1042 		}
1043 		if (stack->sym == last_sym)
1044 			fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1045 				prop->file->name, prop->lineno);
1046 
1047 		if (sym_is_choice(sym)) {
1048 			fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1049 				menu->file->name, menu->lineno,
1050 				sym->name ? sym->name : "<choice>",
1051 				next_sym->name ? next_sym->name : "<choice>");
1052 		} else if (sym_is_choice_value(sym)) {
1053 			fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1054 				menu->file->name, menu->lineno,
1055 				sym->name ? sym->name : "<choice>",
1056 				next_sym->name ? next_sym->name : "<choice>");
1057 		} else if (stack->expr == &sym->dir_dep.expr) {
1058 			fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1059 				prop->file->name, prop->lineno,
1060 				sym->name ? sym->name : "<choice>",
1061 				next_sym->name ? next_sym->name : "<choice>");
1062 		} else if (stack->expr == &sym->rev_dep.expr) {
1063 			fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1064 				prop->file->name, prop->lineno,
1065 				sym->name ? sym->name : "<choice>",
1066 				next_sym->name ? next_sym->name : "<choice>");
1067 		} else if (stack->expr == &sym->implied.expr) {
1068 			fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1069 				prop->file->name, prop->lineno,
1070 				sym->name ? sym->name : "<choice>",
1071 				next_sym->name ? next_sym->name : "<choice>");
1072 		} else if (stack->expr) {
1073 			fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1074 				prop->file->name, prop->lineno,
1075 				sym->name ? sym->name : "<choice>",
1076 				prop_get_type_name(prop->type),
1077 				next_sym->name ? next_sym->name : "<choice>");
1078 		} else {
1079 			fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1080 				prop->file->name, prop->lineno,
1081 				sym->name ? sym->name : "<choice>",
1082 				prop_get_type_name(prop->type),
1083 				next_sym->name ? next_sym->name : "<choice>");
1084 		}
1085 	}
1086 
1087 	fprintf(stderr,
1088 		"For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1089 		"subsection \"Kconfig recursive dependency limitations\"\n"
1090 		"\n");
1091 
1092 	if (check_top == &cv_stack)
1093 		dep_stack_remove();
1094 }
1095 
sym_check_expr_deps(struct expr * e)1096 static struct symbol *sym_check_expr_deps(struct expr *e)
1097 {
1098 	struct symbol *sym;
1099 
1100 	if (!e)
1101 		return NULL;
1102 	switch (e->type) {
1103 	case E_OR:
1104 	case E_AND:
1105 		sym = sym_check_expr_deps(e->left.expr);
1106 		if (sym)
1107 			return sym;
1108 		return sym_check_expr_deps(e->right.expr);
1109 	case E_NOT:
1110 		return sym_check_expr_deps(e->left.expr);
1111 	case E_EQUAL:
1112 	case E_GEQ:
1113 	case E_GTH:
1114 	case E_LEQ:
1115 	case E_LTH:
1116 	case E_UNEQUAL:
1117 		sym = sym_check_deps(e->left.sym);
1118 		if (sym)
1119 			return sym;
1120 		return sym_check_deps(e->right.sym);
1121 	case E_SYMBOL:
1122 		return sym_check_deps(e->left.sym);
1123 	default:
1124 		break;
1125 	}
1126 	fprintf(stderr, "Oops! How to check %d?\n", e->type);
1127 	return NULL;
1128 }
1129 
1130 /* return NULL when dependencies are OK */
sym_check_sym_deps(struct symbol * sym)1131 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1132 {
1133 	struct symbol *sym2;
1134 	struct property *prop;
1135 	struct dep_stack stack;
1136 
1137 	dep_stack_insert(&stack, sym);
1138 
1139 	stack.expr = &sym->dir_dep.expr;
1140 	sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1141 	if (sym2)
1142 		goto out;
1143 
1144 	stack.expr = &sym->rev_dep.expr;
1145 	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1146 	if (sym2)
1147 		goto out;
1148 
1149 	stack.expr = &sym->implied.expr;
1150 	sym2 = sym_check_expr_deps(sym->implied.expr);
1151 	if (sym2)
1152 		goto out;
1153 
1154 	stack.expr = NULL;
1155 
1156 	for (prop = sym->prop; prop; prop = prop->next) {
1157 		if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1158 		    prop->type == P_IMPLY)
1159 			continue;
1160 		stack.prop = prop;
1161 		sym2 = sym_check_expr_deps(prop->visible.expr);
1162 		if (sym2)
1163 			break;
1164 		if (prop->type != P_DEFAULT || sym_is_choice(sym))
1165 			continue;
1166 		stack.expr = &prop->expr;
1167 		sym2 = sym_check_expr_deps(prop->expr);
1168 		if (sym2)
1169 			break;
1170 		stack.expr = NULL;
1171 	}
1172 
1173 out:
1174 	dep_stack_remove();
1175 
1176 	return sym2;
1177 }
1178 
sym_check_choice_deps(struct symbol * choice)1179 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1180 {
1181 	struct symbol *sym, *sym2;
1182 	struct property *prop;
1183 	struct expr *e;
1184 	struct dep_stack stack;
1185 
1186 	dep_stack_insert(&stack, choice);
1187 
1188 	prop = sym_get_choice_prop(choice);
1189 	expr_list_for_each_sym(prop->expr, e, sym)
1190 		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1191 
1192 	choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1193 	sym2 = sym_check_sym_deps(choice);
1194 	choice->flags &= ~SYMBOL_CHECK;
1195 	if (sym2)
1196 		goto out;
1197 
1198 	expr_list_for_each_sym(prop->expr, e, sym) {
1199 		sym2 = sym_check_sym_deps(sym);
1200 		if (sym2)
1201 			break;
1202 	}
1203 out:
1204 	expr_list_for_each_sym(prop->expr, e, sym)
1205 		sym->flags &= ~SYMBOL_CHECK;
1206 
1207 	if (sym2 && sym_is_choice_value(sym2) &&
1208 	    prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1209 		sym2 = choice;
1210 
1211 	dep_stack_remove();
1212 
1213 	return sym2;
1214 }
1215 
sym_check_deps(struct symbol * sym)1216 struct symbol *sym_check_deps(struct symbol *sym)
1217 {
1218 	struct symbol *sym2;
1219 	struct property *prop;
1220 
1221 	if (sym->flags & SYMBOL_CHECK) {
1222 		sym_check_print_recursive(sym);
1223 		return sym;
1224 	}
1225 	if (sym->flags & SYMBOL_CHECKED)
1226 		return NULL;
1227 
1228 	if (sym_is_choice_value(sym)) {
1229 		struct dep_stack stack;
1230 
1231 		/* for choice groups start the check with main choice symbol */
1232 		dep_stack_insert(&stack, sym);
1233 		prop = sym_get_choice_prop(sym);
1234 		sym2 = sym_check_deps(prop_get_symbol(prop));
1235 		dep_stack_remove();
1236 	} else if (sym_is_choice(sym)) {
1237 		sym2 = sym_check_choice_deps(sym);
1238 	} else {
1239 		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1240 		sym2 = sym_check_sym_deps(sym);
1241 		sym->flags &= ~SYMBOL_CHECK;
1242 	}
1243 
1244 	return sym2;
1245 }
1246 
prop_get_symbol(struct property * prop)1247 struct symbol *prop_get_symbol(struct property *prop)
1248 {
1249 	if (prop->expr && (prop->expr->type == E_SYMBOL ||
1250 			   prop->expr->type == E_LIST))
1251 		return prop->expr->left.sym;
1252 	return NULL;
1253 }
1254 
prop_get_type_name(enum prop_type type)1255 const char *prop_get_type_name(enum prop_type type)
1256 {
1257 	switch (type) {
1258 	case P_PROMPT:
1259 		return "prompt";
1260 	case P_COMMENT:
1261 		return "comment";
1262 	case P_MENU:
1263 		return "menu";
1264 	case P_DEFAULT:
1265 		return "default";
1266 	case P_CHOICE:
1267 		return "choice";
1268 	case P_SELECT:
1269 		return "select";
1270 	case P_IMPLY:
1271 		return "imply";
1272 	case P_RANGE:
1273 		return "range";
1274 	case P_SYMBOL:
1275 		return "symbol";
1276 	case P_UNKNOWN:
1277 		break;
1278 	}
1279 	return "unknown";
1280 }
1281