3dc81397d0038495a4a9a11925990a42fedf46ce
[carl9170fw.git] / config / symbol.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
4  */
5
6 #include <ctype.h>
7 #include <stdlib.h>
8 #include <string.h>
9 #include <regex.h>
10 #include <sys/utsname.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 }, symbol_mod = {
19         .name = "m",
20         .curr = { "m", mod },
21         .flags = SYMBOL_CONST|SYMBOL_VALID,
22 }, symbol_no = {
23         .name = "n",
24         .curr = { "n", no },
25         .flags = SYMBOL_CONST|SYMBOL_VALID,
26 }, symbol_empty = {
27         .name = "",
28         .curr = { "", no },
29         .flags = SYMBOL_VALID,
30 };
31
32 struct symbol *sym_defconfig_list;
33 struct symbol *modules_sym;
34 tristate modules_val;
35
36 enum symbol_type sym_get_type(struct symbol *sym)
37 {
38         enum symbol_type type = sym->type;
39
40         if (type == S_TRISTATE) {
41                 if (sym_is_choice_value(sym) && sym->visible == yes)
42                         type = S_BOOLEAN;
43                 else if (modules_val == no)
44                         type = S_BOOLEAN;
45         }
46         return type;
47 }
48
49 const char *sym_type_name(enum symbol_type type)
50 {
51         switch (type) {
52         case S_BOOLEAN:
53                 return "bool";
54         case S_TRISTATE:
55                 return "tristate";
56         case S_INT:
57                 return "integer";
58         case S_HEX:
59                 return "hex";
60         case S_STRING:
61                 return "string";
62         case S_UNKNOWN:
63                 return "unknown";
64         }
65         return "???";
66 }
67
68 struct property *sym_get_choice_prop(struct symbol *sym)
69 {
70         struct property *prop;
71
72         for_all_choices(sym, prop)
73                 return prop;
74         return NULL;
75 }
76
77 static struct property *sym_get_default_prop(struct symbol *sym)
78 {
79         struct property *prop;
80
81         for_all_defaults(sym, prop) {
82                 prop->visible.tri = expr_calc_value(prop->visible.expr);
83                 if (prop->visible.tri != no)
84                         return prop;
85         }
86         return NULL;
87 }
88
89 struct property *sym_get_range_prop(struct symbol *sym)
90 {
91         struct property *prop;
92
93         for_all_properties(sym, prop, P_RANGE) {
94                 prop->visible.tri = expr_calc_value(prop->visible.expr);
95                 if (prop->visible.tri != no)
96                         return prop;
97         }
98         return NULL;
99 }
100
101 static long long sym_get_range_val(struct symbol *sym, int base)
102 {
103         sym_calc_value(sym);
104         switch (sym->type) {
105         case S_INT:
106                 base = 10;
107                 break;
108         case S_HEX:
109                 base = 16;
110                 break;
111         default:
112                 break;
113         }
114         return strtoll(sym->curr.val, NULL, base);
115 }
116
117 static void sym_validate_range(struct symbol *sym)
118 {
119         struct property *prop;
120         int base;
121         long long val, val2;
122         char str[64];
123
124         switch (sym->type) {
125         case S_INT:
126                 base = 10;
127                 break;
128         case S_HEX:
129                 base = 16;
130                 break;
131         default:
132                 return;
133         }
134         prop = sym_get_range_prop(sym);
135         if (!prop)
136                 return;
137         val = strtoll(sym->curr.val, NULL, base);
138         val2 = sym_get_range_val(prop->expr->left.sym, base);
139         if (val >= val2) {
140                 val2 = sym_get_range_val(prop->expr->right.sym, base);
141                 if (val <= val2)
142                         return;
143         }
144         if (sym->type == S_INT)
145                 sprintf(str, "%lld", val2);
146         else
147                 sprintf(str, "0x%llx", val2);
148         sym->curr.val = xstrdup(str);
149 }
150
151 static void sym_set_changed(struct symbol *sym)
152 {
153         struct property *prop;
154
155         sym->flags |= SYMBOL_CHANGED;
156         for (prop = sym->prop; prop; prop = prop->next) {
157                 if (prop->menu)
158                         prop->menu->flags |= MENU_CHANGED;
159         }
160 }
161
162 static void sym_set_all_changed(void)
163 {
164         struct symbol *sym;
165         int i;
166
167         for_all_symbols(i, sym)
168                 sym_set_changed(sym);
169 }
170
171 static void sym_calc_visibility(struct symbol *sym)
172 {
173         struct property *prop;
174         struct symbol *choice_sym = NULL;
175         tristate tri;
176
177         /* any prompt visible? */
178         tri = no;
179
180         if (sym_is_choice_value(sym))
181                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
182
183         for_all_prompts(sym, prop) {
184                 prop->visible.tri = expr_calc_value(prop->visible.expr);
185                 /*
186                  * Tristate choice_values with visibility 'mod' are
187                  * not visible if the corresponding choice's value is
188                  * 'yes'.
189                  */
190                 if (choice_sym && sym->type == S_TRISTATE &&
191                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
192                         prop->visible.tri = no;
193
194                 tri = EXPR_OR(tri, prop->visible.tri);
195         }
196         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
197                 tri = yes;
198         if (sym->visible != tri) {
199                 sym->visible = tri;
200                 sym_set_changed(sym);
201         }
202         if (sym_is_choice_value(sym))
203                 return;
204         /* defaulting to "yes" if no explicit "depends on" are given */
205         tri = yes;
206         if (sym->dir_dep.expr)
207                 tri = expr_calc_value(sym->dir_dep.expr);
208         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
209                 tri = yes;
210         if (sym->dir_dep.tri != tri) {
211                 sym->dir_dep.tri = tri;
212                 sym_set_changed(sym);
213         }
214         tri = no;
215         if (sym->rev_dep.expr)
216                 tri = expr_calc_value(sym->rev_dep.expr);
217         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
218                 tri = yes;
219         if (sym->rev_dep.tri != tri) {
220                 sym->rev_dep.tri = tri;
221                 sym_set_changed(sym);
222         }
223         tri = no;
224         if (sym->implied.expr)
225                 tri = expr_calc_value(sym->implied.expr);
226         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
227                 tri = yes;
228         if (sym->implied.tri != tri) {
229                 sym->implied.tri = tri;
230                 sym_set_changed(sym);
231         }
232 }
233
234 /*
235  * Find the default symbol for a choice.
236  * First try the default values for the choice symbol
237  * Next locate the first visible choice value
238  * Return NULL if none was found
239  */
240 struct symbol *sym_choice_default(struct symbol *sym)
241 {
242         struct symbol *def_sym;
243         struct property *prop;
244         struct expr *e;
245
246         /* any of the defaults visible? */
247         for_all_defaults(sym, prop) {
248                 prop->visible.tri = expr_calc_value(prop->visible.expr);
249                 if (prop->visible.tri == no)
250                         continue;
251                 def_sym = prop_get_symbol(prop);
252                 if (def_sym->visible != no)
253                         return def_sym;
254         }
255
256         /* just get the first visible value */
257         prop = sym_get_choice_prop(sym);
258         expr_list_for_each_sym(prop->expr, e, def_sym)
259                 if (def_sym->visible != no)
260                         return def_sym;
261
262         /* failed to locate any defaults */
263         return NULL;
264 }
265
266 static struct symbol *sym_calc_choice(struct symbol *sym)
267 {
268         struct symbol *def_sym;
269         struct property *prop;
270         struct expr *e;
271         int flags;
272
273         /* first calculate all choice values' visibilities */
274         flags = sym->flags;
275         prop = sym_get_choice_prop(sym);
276         expr_list_for_each_sym(prop->expr, e, def_sym) {
277                 sym_calc_visibility(def_sym);
278                 if (def_sym->visible != no)
279                         flags &= def_sym->flags;
280         }
281
282         sym->flags &= flags | ~SYMBOL_DEF_USER;
283
284         /* is the user choice visible? */
285         def_sym = sym->def[S_DEF_USER].val;
286         if (def_sym && def_sym->visible != no)
287                 return def_sym;
288
289         def_sym = sym_choice_default(sym);
290
291         if (def_sym == NULL)
292                 /* no choice? reset tristate value */
293                 sym->curr.tri = no;
294
295         return def_sym;
296 }
297
298 static void sym_warn_unmet_dep(struct symbol *sym)
299 {
300         struct gstr gs = str_new();
301
302         str_printf(&gs,
303                    "\nWARNING: unmet direct dependencies detected for %s\n",
304                    sym->name);
305         str_printf(&gs,
306                    "  Depends on [%c]: ",
307                    sym->dir_dep.tri == mod ? 'm' : 'n');
308         expr_gstr_print(sym->dir_dep.expr, &gs);
309         str_printf(&gs, "\n");
310
311         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
312                                "  Selected by [y]:\n");
313         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
314                                "  Selected by [m]:\n");
315
316         fputs(str_get(&gs), stderr);
317 }
318
319 void sym_calc_value(struct symbol *sym)
320 {
321         struct symbol_value newval, oldval;
322         struct property *prop;
323         struct expr *e;
324
325         if (!sym)
326                 return;
327
328         if (sym->flags & SYMBOL_VALID)
329                 return;
330
331         if (sym_is_choice_value(sym) &&
332             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
333                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
334                 prop = sym_get_choice_prop(sym);
335                 sym_calc_value(prop_get_symbol(prop));
336         }
337
338         sym->flags |= SYMBOL_VALID;
339
340         oldval = sym->curr;
341
342         switch (sym->type) {
343         case S_INT:
344         case S_HEX:
345         case S_STRING:
346                 newval = symbol_empty.curr;
347                 break;
348         case S_BOOLEAN:
349         case S_TRISTATE:
350                 newval = symbol_no.curr;
351                 break;
352         default:
353                 sym->curr.val = sym->name;
354                 sym->curr.tri = no;
355                 return;
356         }
357         sym->flags &= ~SYMBOL_WRITE;
358
359         sym_calc_visibility(sym);
360
361         if (sym->visible != no)
362                 sym->flags |= SYMBOL_WRITE;
363
364         /* set default if recursively called */
365         sym->curr = newval;
366
367         switch (sym_get_type(sym)) {
368         case S_BOOLEAN:
369         case S_TRISTATE:
370                 if (sym_is_choice_value(sym) && sym->visible == yes) {
371                         prop = sym_get_choice_prop(sym);
372                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
373                 } else {
374                         if (sym->visible != no) {
375                                 /* if the symbol is visible use the user value
376                                  * if available, otherwise try the default value
377                                  */
378                                 if (sym_has_value(sym)) {
379                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
380                                                               sym->visible);
381                                         goto calc_newval;
382                                 }
383                         }
384                         if (sym->rev_dep.tri != no)
385                                 sym->flags |= SYMBOL_WRITE;
386                         if (!sym_is_choice(sym)) {
387                                 prop = sym_get_default_prop(sym);
388                                 if (prop) {
389                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
390                                                               prop->visible.tri);
391                                         if (newval.tri != no)
392                                                 sym->flags |= SYMBOL_WRITE;
393                                 }
394                                 if (sym->implied.tri != no) {
395                                         sym->flags |= SYMBOL_WRITE;
396                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
397                                         newval.tri = EXPR_AND(newval.tri,
398                                                               sym->dir_dep.tri);
399                                 }
400                         }
401                 calc_newval:
402                         if (sym->dir_dep.tri < sym->rev_dep.tri)
403                                 sym_warn_unmet_dep(sym);
404                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
405                 }
406                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
407                         newval.tri = yes;
408                 break;
409         case S_STRING:
410         case S_HEX:
411         case S_INT:
412                 if (sym->visible != no && sym_has_value(sym)) {
413                         newval.val = sym->def[S_DEF_USER].val;
414                         break;
415                 }
416                 prop = sym_get_default_prop(sym);
417                 if (prop) {
418                         struct symbol *ds = prop_get_symbol(prop);
419                         if (ds) {
420                                 sym->flags |= SYMBOL_WRITE;
421                                 sym_calc_value(ds);
422                                 newval.val = ds->curr.val;
423                         }
424                 }
425                 break;
426         default:
427                 ;
428         }
429
430         sym->curr = newval;
431         if (sym_is_choice(sym) && newval.tri == yes)
432                 sym->curr.val = sym_calc_choice(sym);
433         sym_validate_range(sym);
434
435         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
436                 sym_set_changed(sym);
437                 if (modules_sym == sym) {
438                         sym_set_all_changed();
439                         modules_val = modules_sym->curr.tri;
440                 }
441         }
442
443         if (sym_is_choice(sym)) {
444                 struct symbol *choice_sym;
445
446                 prop = sym_get_choice_prop(sym);
447                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
448                         if ((sym->flags & SYMBOL_WRITE) &&
449                             choice_sym->visible != no)
450                                 choice_sym->flags |= SYMBOL_WRITE;
451                         if (sym->flags & SYMBOL_CHANGED)
452                                 sym_set_changed(choice_sym);
453                 }
454         }
455
456         if (sym->flags & SYMBOL_NO_WRITE)
457                 sym->flags &= ~SYMBOL_WRITE;
458
459         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
460                 set_all_choice_values(sym);
461 }
462
463 void sym_clear_all_valid(void)
464 {
465         struct symbol *sym;
466         int i;
467
468         for_all_symbols(i, sym)
469                 sym->flags &= ~SYMBOL_VALID;
470         sym_add_change_count(1);
471         sym_calc_value(modules_sym);
472 }
473
474 bool sym_tristate_within_range(struct symbol *sym, tristate val)
475 {
476         int type = sym_get_type(sym);
477
478         if (sym->visible == no)
479                 return false;
480
481         if (type != S_BOOLEAN && type != S_TRISTATE)
482                 return false;
483
484         if (type == S_BOOLEAN && val == mod)
485                 return false;
486         if (sym->visible <= sym->rev_dep.tri)
487                 return false;
488         if (sym_is_choice_value(sym) && sym->visible == yes)
489                 return val == yes;
490         return val >= sym->rev_dep.tri && val <= sym->visible;
491 }
492
493 bool sym_set_tristate_value(struct symbol *sym, tristate val)
494 {
495         tristate oldval = sym_get_tristate_value(sym);
496
497         if (oldval != val && !sym_tristate_within_range(sym, val))
498                 return false;
499
500         if (!(sym->flags & SYMBOL_DEF_USER)) {
501                 sym->flags |= SYMBOL_DEF_USER;
502                 sym_set_changed(sym);
503         }
504         /*
505          * setting a choice value also resets the new flag of the choice
506          * symbol and all other choice values.
507          */
508         if (sym_is_choice_value(sym) && val == yes) {
509                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
510                 struct property *prop;
511                 struct expr *e;
512
513                 cs->def[S_DEF_USER].val = sym;
514                 cs->flags |= SYMBOL_DEF_USER;
515                 prop = sym_get_choice_prop(cs);
516                 for (e = prop->expr; e; e = e->left.expr) {
517                         if (e->right.sym->visible != no)
518                                 e->right.sym->flags |= SYMBOL_DEF_USER;
519                 }
520         }
521
522         sym->def[S_DEF_USER].tri = val;
523         if (oldval != val)
524                 sym_clear_all_valid();
525
526         return true;
527 }
528
529 tristate sym_toggle_tristate_value(struct symbol *sym)
530 {
531         tristate oldval, newval;
532
533         oldval = newval = sym_get_tristate_value(sym);
534         do {
535                 switch (newval) {
536                 case no:
537                         newval = mod;
538                         break;
539                 case mod:
540                         newval = yes;
541                         break;
542                 case yes:
543                         newval = no;
544                         break;
545                 }
546                 if (sym_set_tristate_value(sym, newval))
547                         break;
548         } while (oldval != newval);
549         return newval;
550 }
551
552 bool sym_string_valid(struct symbol *sym, const char *str)
553 {
554         signed char ch;
555
556         switch (sym->type) {
557         case S_STRING:
558                 return true;
559         case S_INT:
560                 ch = *str++;
561                 if (ch == '-')
562                         ch = *str++;
563                 if (!isdigit(ch))
564                         return false;
565                 if (ch == '0' && *str != 0)
566                         return false;
567                 while ((ch = *str++)) {
568                         if (!isdigit(ch))
569                                 return false;
570                 }
571                 return true;
572         case S_HEX:
573                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
574                         str += 2;
575                 ch = *str++;
576                 do {
577                         if (!isxdigit(ch))
578                                 return false;
579                 } while ((ch = *str++));
580                 return true;
581         case S_BOOLEAN:
582         case S_TRISTATE:
583                 switch (str[0]) {
584                 case 'y': case 'Y':
585                 case 'm': case 'M':
586                 case 'n': case 'N':
587                         return true;
588                 }
589                 return false;
590         default:
591                 return false;
592         }
593 }
594
595 bool sym_string_within_range(struct symbol *sym, const char *str)
596 {
597         struct property *prop;
598         long long val;
599
600         switch (sym->type) {
601         case S_STRING:
602                 return sym_string_valid(sym, str);
603         case S_INT:
604                 if (!sym_string_valid(sym, str))
605                         return false;
606                 prop = sym_get_range_prop(sym);
607                 if (!prop)
608                         return true;
609                 val = strtoll(str, NULL, 10);
610                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
611                        val <= sym_get_range_val(prop->expr->right.sym, 10);
612         case S_HEX:
613                 if (!sym_string_valid(sym, str))
614                         return false;
615                 prop = sym_get_range_prop(sym);
616                 if (!prop)
617                         return true;
618                 val = strtoll(str, NULL, 16);
619                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
620                        val <= sym_get_range_val(prop->expr->right.sym, 16);
621         case S_BOOLEAN:
622         case S_TRISTATE:
623                 switch (str[0]) {
624                 case 'y': case 'Y':
625                         return sym_tristate_within_range(sym, yes);
626                 case 'm': case 'M':
627                         return sym_tristate_within_range(sym, mod);
628                 case 'n': case 'N':
629                         return sym_tristate_within_range(sym, no);
630                 }
631                 return false;
632         default:
633                 return false;
634         }
635 }
636
637 bool sym_set_string_value(struct symbol *sym, const char *newval)
638 {
639         const char *oldval;
640         char *val;
641         int size;
642
643         switch (sym->type) {
644         case S_BOOLEAN:
645         case S_TRISTATE:
646                 switch (newval[0]) {
647                 case 'y': case 'Y':
648                         return sym_set_tristate_value(sym, yes);
649                 case 'm': case 'M':
650                         return sym_set_tristate_value(sym, mod);
651                 case 'n': case 'N':
652                         return sym_set_tristate_value(sym, no);
653                 }
654                 return false;
655         default:
656                 ;
657         }
658
659         if (!sym_string_within_range(sym, newval))
660                 return false;
661
662         if (!(sym->flags & SYMBOL_DEF_USER)) {
663                 sym->flags |= SYMBOL_DEF_USER;
664                 sym_set_changed(sym);
665         }
666
667         oldval = sym->def[S_DEF_USER].val;
668         size = strlen(newval) + 1;
669         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
670                 size += 2;
671                 sym->def[S_DEF_USER].val = val = xmalloc(size);
672                 *val++ = '0';
673                 *val++ = 'x';
674         } else if (!oldval || strcmp(oldval, newval))
675                 sym->def[S_DEF_USER].val = val = xmalloc(size);
676         else
677                 return true;
678
679         strcpy(val, newval);
680         free((void *)oldval);
681         sym_clear_all_valid();
682
683         return true;
684 }
685
686 /*
687  * Find the default value associated to a symbol.
688  * For tristate symbol handle the modules=n case
689  * in which case "m" becomes "y".
690  * If the symbol does not have any default then fallback
691  * to the fixed default values.
692  */
693 const char *sym_get_string_default(struct symbol *sym)
694 {
695         struct property *prop;
696         struct symbol *ds;
697         const char *str;
698         tristate val;
699
700         sym_calc_visibility(sym);
701         sym_calc_value(modules_sym);
702         val = symbol_no.curr.tri;
703         str = symbol_empty.curr.val;
704
705         /* If symbol has a default value look it up */
706         prop = sym_get_default_prop(sym);
707         if (prop != NULL) {
708                 switch (sym->type) {
709                 case S_BOOLEAN:
710                 case S_TRISTATE:
711                         /* The visibility may limit the value from yes => mod */
712                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
713                         break;
714                 default:
715                         /*
716                          * The following fails to handle the situation
717                          * where a default value is further limited by
718                          * the valid range.
719                          */
720                         ds = prop_get_symbol(prop);
721                         if (ds != NULL) {
722                                 sym_calc_value(ds);
723                                 str = (const char *)ds->curr.val;
724                         }
725                 }
726         }
727
728         /* Handle select statements */
729         val = EXPR_OR(val, sym->rev_dep.tri);
730
731         /* transpose mod to yes if modules are not enabled */
732         if (val == mod)
733                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
734                         val = yes;
735
736         /* transpose mod to yes if type is bool */
737         if (sym->type == S_BOOLEAN && val == mod)
738                 val = yes;
739
740         /* adjust the default value if this symbol is implied by another */
741         if (val < sym->implied.tri)
742                 val = sym->implied.tri;
743
744         switch (sym->type) {
745         case S_BOOLEAN:
746         case S_TRISTATE:
747                 switch (val) {
748                 case no: return "n";
749                 case mod: return "m";
750                 case yes: return "y";
751                 }
752         case S_INT:
753         case S_HEX:
754                 return str;
755         case S_STRING:
756                 return str;
757         case S_UNKNOWN:
758                 break;
759         }
760         return "";
761 }
762
763 const char *sym_get_string_value(struct symbol *sym)
764 {
765         tristate val;
766
767         switch (sym->type) {
768         case S_BOOLEAN:
769         case S_TRISTATE:
770                 val = sym_get_tristate_value(sym);
771                 switch (val) {
772                 case no:
773                         return "n";
774                 case mod:
775                         sym_calc_value(modules_sym);
776                         return (modules_sym->curr.tri == no) ? "n" : "m";
777                 case yes:
778                         return "y";
779                 }
780                 break;
781         default:
782                 ;
783         }
784         return (const char *)sym->curr.val;
785 }
786
787 bool sym_is_changeable(struct symbol *sym)
788 {
789         return sym->visible > sym->rev_dep.tri;
790 }
791
792 static unsigned strhash(const char *s)
793 {
794         /* fnv32 hash */
795         unsigned hash = 2166136261U;
796         for (; *s; s++)
797                 hash = (hash ^ *s) * 0x01000193;
798         return hash;
799 }
800
801 struct symbol *sym_lookup(const char *name, int flags)
802 {
803         struct symbol *symbol;
804         char *new_name;
805         int hash;
806
807         if (name) {
808                 if (name[0] && !name[1]) {
809                         switch (name[0]) {
810                         case 'y': return &symbol_yes;
811                         case 'm': return &symbol_mod;
812                         case 'n': return &symbol_no;
813                         }
814                 }
815                 hash = strhash(name) % SYMBOL_HASHSIZE;
816
817                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
818                         if (symbol->name &&
819                             !strcmp(symbol->name, name) &&
820                             (flags ? symbol->flags & flags
821                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
822                                 return symbol;
823                 }
824                 new_name = xstrdup(name);
825         } else {
826                 new_name = NULL;
827                 hash = 0;
828         }
829
830         symbol = xmalloc(sizeof(*symbol));
831         memset(symbol, 0, sizeof(*symbol));
832         symbol->name = new_name;
833         symbol->type = S_UNKNOWN;
834         symbol->flags |= flags;
835
836         symbol->next = symbol_hash[hash];
837         symbol_hash[hash] = symbol;
838
839         return symbol;
840 }
841
842 struct symbol *sym_find(const char *name)
843 {
844         struct symbol *symbol = NULL;
845         int hash = 0;
846
847         if (!name)
848                 return NULL;
849
850         if (name[0] && !name[1]) {
851                 switch (name[0]) {
852                 case 'y': return &symbol_yes;
853                 case 'm': return &symbol_mod;
854                 case 'n': return &symbol_no;
855                 }
856         }
857         hash = strhash(name) % SYMBOL_HASHSIZE;
858
859         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
860                 if (symbol->name &&
861                     !strcmp(symbol->name, name) &&
862                     !(symbol->flags & SYMBOL_CONST))
863                                 break;
864         }
865
866         return symbol;
867 }
868
869 const char *sym_escape_string_value(const char *in)
870 {
871         const char *p;
872         size_t reslen;
873         char *res;
874         size_t l;
875
876         reslen = strlen(in) + strlen("\"\"") + 1;
877
878         p = in;
879         for (;;) {
880                 l = strcspn(p, "\"\\");
881                 p += l;
882
883                 if (p[0] == '\0')
884                         break;
885
886                 reslen++;
887                 p++;
888         }
889
890         res = xmalloc(reslen);
891         res[0] = '\0';
892
893         strcat(res, "\"");
894
895         p = in;
896         for (;;) {
897                 l = strcspn(p, "\"\\");
898                 strncat(res, p, l);
899                 p += l;
900
901                 if (p[0] == '\0')
902                         break;
903
904                 strcat(res, "\\");
905                 strncat(res, p++, 1);
906         }
907
908         strcat(res, "\"");
909         return res;
910 }
911
912 struct sym_match {
913         struct symbol   *sym;
914         off_t           so, eo;
915 };
916
917 /* Compare matched symbols as thus:
918  * - first, symbols that match exactly
919  * - then, alphabetical sort
920  */
921 static int sym_rel_comp(const void *sym1, const void *sym2)
922 {
923         const struct sym_match *s1 = sym1;
924         const struct sym_match *s2 = sym2;
925         int exact1, exact2;
926
927         /* Exact match:
928          * - if matched length on symbol s1 is the length of that symbol,
929          *   then this symbol should come first;
930          * - if matched length on symbol s2 is the length of that symbol,
931          *   then this symbol should come first.
932          * Note: since the search can be a regexp, both symbols may match
933          * exactly; if this is the case, we can't decide which comes first,
934          * and we fallback to sorting alphabetically.
935          */
936         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
937         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
938         if (exact1 && !exact2)
939                 return -1;
940         if (!exact1 && exact2)
941                 return 1;
942
943         /* As a fallback, sort symbols alphabetically */
944         return strcmp(s1->sym->name, s2->sym->name);
945 }
946
947 struct symbol **sym_re_search(const char *pattern)
948 {
949         struct symbol *sym, **sym_arr = NULL;
950         struct sym_match *sym_match_arr = NULL;
951         int i, cnt, size;
952         regex_t re;
953         regmatch_t match[1];
954
955         cnt = size = 0;
956         /* Skip if empty */
957         if (strlen(pattern) == 0)
958                 return NULL;
959         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
960                 return NULL;
961
962         for_all_symbols(i, sym) {
963                 if (sym->flags & SYMBOL_CONST || !sym->name)
964                         continue;
965                 if (regexec(&re, sym->name, 1, match, 0))
966                         continue;
967                 if (cnt >= size) {
968                         void *tmp;
969                         size += 16;
970                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
971                         if (!tmp)
972                                 goto sym_re_search_free;
973                         sym_match_arr = tmp;
974                 }
975                 sym_calc_value(sym);
976                 /* As regexec returned 0, we know we have a match, so
977                  * we can use match[0].rm_[se]o without further checks
978                  */
979                 sym_match_arr[cnt].so = match[0].rm_so;
980                 sym_match_arr[cnt].eo = match[0].rm_eo;
981                 sym_match_arr[cnt++].sym = sym;
982         }
983         if (sym_match_arr) {
984                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
985                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
986                 if (!sym_arr)
987                         goto sym_re_search_free;
988                 for (i = 0; i < cnt; i++)
989                         sym_arr[i] = sym_match_arr[i].sym;
990                 sym_arr[cnt] = NULL;
991         }
992 sym_re_search_free:
993         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
994         free(sym_match_arr);
995         regfree(&re);
996
997         return sym_arr;
998 }
999
1000 /*
1001  * When we check for recursive dependencies we use a stack to save
1002  * current state so we can print out relevant info to user.
1003  * The entries are located on the call stack so no need to free memory.
1004  * Note insert() remove() must always match to properly clear the stack.
1005  */
1006 static struct dep_stack {
1007         struct dep_stack *prev, *next;
1008         struct symbol *sym;
1009         struct property *prop;
1010         struct expr **expr;
1011 } *check_top;
1012
1013 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1014 {
1015         memset(stack, 0, sizeof(*stack));
1016         if (check_top)
1017                 check_top->next = stack;
1018         stack->prev = check_top;
1019         stack->sym = sym;
1020         check_top = stack;
1021 }
1022
1023 static void dep_stack_remove(void)
1024 {
1025         check_top = check_top->prev;
1026         if (check_top)
1027                 check_top->next = NULL;
1028 }
1029
1030 /*
1031  * Called when we have detected a recursive dependency.
1032  * check_top point to the top of the stact so we use
1033  * the ->prev pointer to locate the bottom of the stack.
1034  */
1035 static void sym_check_print_recursive(struct symbol *last_sym)
1036 {
1037         struct dep_stack *stack;
1038         struct symbol *sym, *next_sym;
1039         struct menu *menu = NULL;
1040         struct property *prop;
1041         struct dep_stack cv_stack;
1042
1043         if (sym_is_choice_value(last_sym)) {
1044                 dep_stack_insert(&cv_stack, last_sym);
1045                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1046         }
1047
1048         for (stack = check_top; stack != NULL; stack = stack->prev)
1049                 if (stack->sym == last_sym)
1050                         break;
1051         if (!stack) {
1052                 fprintf(stderr, "unexpected recursive dependency error\n");
1053                 return;
1054         }
1055
1056         for (; stack; stack = stack->next) {
1057                 sym = stack->sym;
1058                 next_sym = stack->next ? stack->next->sym : last_sym;
1059                 prop = stack->prop;
1060                 if (prop == NULL)
1061                         prop = stack->sym->prop;
1062
1063                 /* for choice values find the menu entry (used below) */
1064                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1065                         for (prop = sym->prop; prop; prop = prop->next) {
1066                                 menu = prop->menu;
1067                                 if (prop->menu)
1068                                         break;
1069                         }
1070                 }
1071                 if (stack->sym == last_sym)
1072                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1073                                 prop->file->name, prop->lineno);
1074
1075                 if (sym_is_choice(sym)) {
1076                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1077                                 menu->file->name, menu->lineno,
1078                                 sym->name ? sym->name : "<choice>",
1079                                 next_sym->name ? next_sym->name : "<choice>");
1080                 } else if (sym_is_choice_value(sym)) {
1081                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1082                                 menu->file->name, menu->lineno,
1083                                 sym->name ? sym->name : "<choice>",
1084                                 next_sym->name ? next_sym->name : "<choice>");
1085                 } else if (stack->expr == &sym->dir_dep.expr) {
1086                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1087                                 prop->file->name, prop->lineno,
1088                                 sym->name ? sym->name : "<choice>",
1089                                 next_sym->name ? next_sym->name : "<choice>");
1090                 } else if (stack->expr == &sym->rev_dep.expr) {
1091                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1092                                 prop->file->name, prop->lineno,
1093                                 sym->name ? sym->name : "<choice>",
1094                                 next_sym->name ? next_sym->name : "<choice>");
1095                 } else if (stack->expr == &sym->implied.expr) {
1096                         fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1097                                 prop->file->name, prop->lineno,
1098                                 sym->name ? sym->name : "<choice>",
1099                                 next_sym->name ? next_sym->name : "<choice>");
1100                 } else if (stack->expr) {
1101                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1102                                 prop->file->name, prop->lineno,
1103                                 sym->name ? sym->name : "<choice>",
1104                                 prop_get_type_name(prop->type),
1105                                 next_sym->name ? next_sym->name : "<choice>");
1106                 } else {
1107                         fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1108                                 prop->file->name, prop->lineno,
1109                                 sym->name ? sym->name : "<choice>",
1110                                 prop_get_type_name(prop->type),
1111                                 next_sym->name ? next_sym->name : "<choice>");
1112                 }
1113         }
1114
1115         fprintf(stderr,
1116                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1117                 "subsection \"Kconfig recursive dependency limitations\"\n"
1118                 "\n");
1119
1120         if (check_top == &cv_stack)
1121                 dep_stack_remove();
1122 }
1123
1124 static struct symbol *sym_check_expr_deps(struct expr *e)
1125 {
1126         struct symbol *sym;
1127
1128         if (!e)
1129                 return NULL;
1130         switch (e->type) {
1131         case E_OR:
1132         case E_AND:
1133                 sym = sym_check_expr_deps(e->left.expr);
1134                 if (sym)
1135                         return sym;
1136                 return sym_check_expr_deps(e->right.expr);
1137         case E_NOT:
1138                 return sym_check_expr_deps(e->left.expr);
1139         case E_EQUAL:
1140         case E_GEQ:
1141         case E_GTH:
1142         case E_LEQ:
1143         case E_LTH:
1144         case E_UNEQUAL:
1145                 sym = sym_check_deps(e->left.sym);
1146                 if (sym)
1147                         return sym;
1148                 return sym_check_deps(e->right.sym);
1149         case E_SYMBOL:
1150                 return sym_check_deps(e->left.sym);
1151         default:
1152                 break;
1153         }
1154         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1155         return NULL;
1156 }
1157
1158 /* return NULL when dependencies are OK */
1159 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1160 {
1161         struct symbol *sym2;
1162         struct property *prop;
1163         struct dep_stack stack;
1164
1165         dep_stack_insert(&stack, sym);
1166
1167         stack.expr = &sym->dir_dep.expr;
1168         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1169         if (sym2)
1170                 goto out;
1171
1172         stack.expr = &sym->rev_dep.expr;
1173         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1174         if (sym2)
1175                 goto out;
1176
1177         stack.expr = &sym->implied.expr;
1178         sym2 = sym_check_expr_deps(sym->implied.expr);
1179         if (sym2)
1180                 goto out;
1181
1182         stack.expr = NULL;
1183
1184         for (prop = sym->prop; prop; prop = prop->next) {
1185                 if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1186                     prop->type == P_IMPLY)
1187                         continue;
1188                 stack.prop = prop;
1189                 sym2 = sym_check_expr_deps(prop->visible.expr);
1190                 if (sym2)
1191                         break;
1192                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1193                         continue;
1194                 stack.expr = &prop->expr;
1195                 sym2 = sym_check_expr_deps(prop->expr);
1196                 if (sym2)
1197                         break;
1198                 stack.expr = NULL;
1199         }
1200
1201 out:
1202         dep_stack_remove();
1203
1204         return sym2;
1205 }
1206
1207 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1208 {
1209         struct symbol *sym, *sym2;
1210         struct property *prop;
1211         struct expr *e;
1212         struct dep_stack stack;
1213
1214         dep_stack_insert(&stack, choice);
1215
1216         prop = sym_get_choice_prop(choice);
1217         expr_list_for_each_sym(prop->expr, e, sym)
1218                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1219
1220         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1221         sym2 = sym_check_sym_deps(choice);
1222         choice->flags &= ~SYMBOL_CHECK;
1223         if (sym2)
1224                 goto out;
1225
1226         expr_list_for_each_sym(prop->expr, e, sym) {
1227                 sym2 = sym_check_sym_deps(sym);
1228                 if (sym2)
1229                         break;
1230         }
1231 out:
1232         expr_list_for_each_sym(prop->expr, e, sym)
1233                 sym->flags &= ~SYMBOL_CHECK;
1234
1235         if (sym2 && sym_is_choice_value(sym2) &&
1236             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1237                 sym2 = choice;
1238
1239         dep_stack_remove();
1240
1241         return sym2;
1242 }
1243
1244 struct symbol *sym_check_deps(struct symbol *sym)
1245 {
1246         struct symbol *sym2;
1247         struct property *prop;
1248
1249         if (sym->flags & SYMBOL_CHECK) {
1250                 sym_check_print_recursive(sym);
1251                 return sym;
1252         }
1253         if (sym->flags & SYMBOL_CHECKED)
1254                 return NULL;
1255
1256         if (sym_is_choice_value(sym)) {
1257                 struct dep_stack stack;
1258
1259                 /* for choice groups start the check with main choice symbol */
1260                 dep_stack_insert(&stack, sym);
1261                 prop = sym_get_choice_prop(sym);
1262                 sym2 = sym_check_deps(prop_get_symbol(prop));
1263                 dep_stack_remove();
1264         } else if (sym_is_choice(sym)) {
1265                 sym2 = sym_check_choice_deps(sym);
1266         } else {
1267                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1268                 sym2 = sym_check_sym_deps(sym);
1269                 sym->flags &= ~SYMBOL_CHECK;
1270         }
1271
1272         return sym2;
1273 }
1274
1275 struct symbol *prop_get_symbol(struct property *prop)
1276 {
1277         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1278                            prop->expr->type == E_LIST))
1279                 return prop->expr->left.sym;
1280         return NULL;
1281 }
1282
1283 const char *prop_get_type_name(enum prop_type type)
1284 {
1285         switch (type) {
1286         case P_PROMPT:
1287                 return "prompt";
1288         case P_COMMENT:
1289                 return "comment";
1290         case P_MENU:
1291                 return "menu";
1292         case P_DEFAULT:
1293                 return "default";
1294         case P_CHOICE:
1295                 return "choice";
1296         case P_SELECT:
1297                 return "select";
1298         case P_IMPLY:
1299                 return "imply";
1300         case P_RANGE:
1301                 return "range";
1302         case P_SYMBOL:
1303                 return "symbol";
1304         case P_UNKNOWN:
1305                 break;
1306         }
1307         return "unknown";
1308 }