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