Merge tag 'icc-6.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc...
[linux-2.6-microblaze.git] / scripts / kconfig / symbol.c
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
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
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
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
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
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
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
122 static void sym_validate_range(struct symbol *sym)
123 {
124         struct property *prop;
125         struct symbol *range_sym;
126         int base;
127         long long val, val2;
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         range_sym = prop->expr->left.sym;
144         val2 = sym_get_range_val(range_sym, base);
145         if (val >= val2) {
146                 range_sym = prop->expr->right.sym;
147                 val2 = sym_get_range_val(range_sym, base);
148                 if (val <= val2)
149                         return;
150         }
151         sym->curr.val = range_sym->curr.val;
152 }
153
154 static void sym_set_changed(struct symbol *sym)
155 {
156         struct property *prop;
157
158         sym->flags |= SYMBOL_CHANGED;
159         for (prop = sym->prop; prop; prop = prop->next) {
160                 if (prop->menu)
161                         prop->menu->flags |= MENU_CHANGED;
162         }
163 }
164
165 static void sym_set_all_changed(void)
166 {
167         struct symbol *sym;
168         int i;
169
170         for_all_symbols(i, sym)
171                 sym_set_changed(sym);
172 }
173
174 static void sym_calc_visibility(struct symbol *sym)
175 {
176         struct property *prop;
177         struct symbol *choice_sym = NULL;
178         tristate tri;
179
180         /* any prompt visible? */
181         tri = no;
182
183         if (sym_is_choice_value(sym))
184                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
185
186         for_all_prompts(sym, prop) {
187                 prop->visible.tri = expr_calc_value(prop->visible.expr);
188                 /*
189                  * Tristate choice_values with visibility 'mod' are
190                  * not visible if the corresponding choice's value is
191                  * 'yes'.
192                  */
193                 if (choice_sym && sym->type == S_TRISTATE &&
194                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
195                         prop->visible.tri = no;
196
197                 tri = EXPR_OR(tri, prop->visible.tri);
198         }
199         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
200                 tri = yes;
201         if (sym->visible != tri) {
202                 sym->visible = tri;
203                 sym_set_changed(sym);
204         }
205         if (sym_is_choice_value(sym))
206                 return;
207         /* defaulting to "yes" if no explicit "depends on" are given */
208         tri = yes;
209         if (sym->dir_dep.expr)
210                 tri = expr_calc_value(sym->dir_dep.expr);
211         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
212                 tri = yes;
213         if (sym->dir_dep.tri != tri) {
214                 sym->dir_dep.tri = tri;
215                 sym_set_changed(sym);
216         }
217         tri = no;
218         if (sym->rev_dep.expr)
219                 tri = expr_calc_value(sym->rev_dep.expr);
220         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
221                 tri = yes;
222         if (sym->rev_dep.tri != tri) {
223                 sym->rev_dep.tri = tri;
224                 sym_set_changed(sym);
225         }
226         tri = no;
227         if (sym->implied.expr)
228                 tri = expr_calc_value(sym->implied.expr);
229         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
230                 tri = yes;
231         if (sym->implied.tri != tri) {
232                 sym->implied.tri = tri;
233                 sym_set_changed(sym);
234         }
235 }
236
237 /*
238  * Find the default symbol for a choice.
239  * First try the default values for the choice symbol
240  * Next locate the first visible choice value
241  * Return NULL if none was found
242  */
243 struct symbol *sym_choice_default(struct symbol *sym)
244 {
245         struct symbol *def_sym;
246         struct property *prop;
247         struct expr *e;
248
249         /* any of the defaults visible? */
250         for_all_defaults(sym, prop) {
251                 prop->visible.tri = expr_calc_value(prop->visible.expr);
252                 if (prop->visible.tri == no)
253                         continue;
254                 def_sym = prop_get_symbol(prop);
255                 if (def_sym->visible != no)
256                         return def_sym;
257         }
258
259         /* just get the first visible value */
260         prop = sym_get_choice_prop(sym);
261         expr_list_for_each_sym(prop->expr, e, def_sym)
262                 if (def_sym->visible != no)
263                         return def_sym;
264
265         /* failed to locate any defaults */
266         return NULL;
267 }
268
269 static struct symbol *sym_calc_choice(struct symbol *sym)
270 {
271         struct symbol *def_sym;
272         struct property *prop;
273         struct expr *e;
274         int flags;
275
276         /* first calculate all choice values' visibilities */
277         flags = sym->flags;
278         prop = sym_get_choice_prop(sym);
279         expr_list_for_each_sym(prop->expr, e, def_sym) {
280                 sym_calc_visibility(def_sym);
281                 if (def_sym->visible != no)
282                         flags &= def_sym->flags;
283         }
284
285         sym->flags &= flags | ~SYMBOL_DEF_USER;
286
287         /* is the user choice visible? */
288         def_sym = sym->def[S_DEF_USER].val;
289         if (def_sym && def_sym->visible != no)
290                 return def_sym;
291
292         def_sym = sym_choice_default(sym);
293
294         if (def_sym == NULL)
295                 /* no choice? reset tristate value */
296                 sym->curr.tri = no;
297
298         return def_sym;
299 }
300
301 static void sym_warn_unmet_dep(struct symbol *sym)
302 {
303         struct gstr gs = str_new();
304
305         str_printf(&gs,
306                    "\nWARNING: unmet direct dependencies detected for %s\n",
307                    sym->name);
308         str_printf(&gs,
309                    "  Depends on [%c]: ",
310                    sym->dir_dep.tri == mod ? 'm' : 'n');
311         expr_gstr_print(sym->dir_dep.expr, &gs);
312         str_printf(&gs, "\n");
313
314         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
315                                "  Selected by [y]:\n");
316         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
317                                "  Selected by [m]:\n");
318
319         fputs(str_get(&gs), stderr);
320 }
321
322 void sym_calc_value(struct symbol *sym)
323 {
324         struct symbol_value newval, oldval;
325         struct property *prop;
326         struct expr *e;
327
328         if (!sym)
329                 return;
330
331         if (sym->flags & SYMBOL_VALID)
332                 return;
333
334         if (sym_is_choice_value(sym) &&
335             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
336                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
337                 prop = sym_get_choice_prop(sym);
338                 sym_calc_value(prop_get_symbol(prop));
339         }
340
341         sym->flags |= SYMBOL_VALID;
342
343         oldval = sym->curr;
344
345         switch (sym->type) {
346         case S_INT:
347         case S_HEX:
348         case S_STRING:
349                 newval = symbol_empty.curr;
350                 break;
351         case S_BOOLEAN:
352         case S_TRISTATE:
353                 newval = symbol_no.curr;
354                 break;
355         default:
356                 sym->curr.val = sym->name;
357                 sym->curr.tri = no;
358                 return;
359         }
360         sym->flags &= ~SYMBOL_WRITE;
361
362         sym_calc_visibility(sym);
363
364         if (sym->visible != no)
365                 sym->flags |= SYMBOL_WRITE;
366
367         /* set default if recursively called */
368         sym->curr = newval;
369
370         switch (sym_get_type(sym)) {
371         case S_BOOLEAN:
372         case S_TRISTATE:
373                 if (sym_is_choice_value(sym) && sym->visible == yes) {
374                         prop = sym_get_choice_prop(sym);
375                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
376                 } else {
377                         if (sym->visible != no) {
378                                 /* if the symbol is visible use the user value
379                                  * if available, otherwise try the default value
380                                  */
381                                 if (sym_has_value(sym)) {
382                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
383                                                               sym->visible);
384                                         goto calc_newval;
385                                 }
386                         }
387                         if (sym->rev_dep.tri != no)
388                                 sym->flags |= SYMBOL_WRITE;
389                         if (!sym_is_choice(sym)) {
390                                 prop = sym_get_default_prop(sym);
391                                 if (prop) {
392                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
393                                                               prop->visible.tri);
394                                         if (newval.tri != no)
395                                                 sym->flags |= SYMBOL_WRITE;
396                                 }
397                                 if (sym->implied.tri != no) {
398                                         sym->flags |= SYMBOL_WRITE;
399                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
400                                         newval.tri = EXPR_AND(newval.tri,
401                                                               sym->dir_dep.tri);
402                                 }
403                         }
404                 calc_newval:
405                         if (sym->dir_dep.tri < sym->rev_dep.tri)
406                                 sym_warn_unmet_dep(sym);
407                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
408                 }
409                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
410                         newval.tri = yes;
411                 break;
412         case S_STRING:
413         case S_HEX:
414         case S_INT:
415                 if (sym->visible != no && sym_has_value(sym)) {
416                         newval.val = sym->def[S_DEF_USER].val;
417                         break;
418                 }
419                 prop = sym_get_default_prop(sym);
420                 if (prop) {
421                         struct symbol *ds = prop_get_symbol(prop);
422                         if (ds) {
423                                 sym->flags |= SYMBOL_WRITE;
424                                 sym_calc_value(ds);
425                                 newval.val = ds->curr.val;
426                         }
427                 }
428                 break;
429         default:
430                 ;
431         }
432
433         sym->curr = newval;
434         if (sym_is_choice(sym) && newval.tri == yes)
435                 sym->curr.val = sym_calc_choice(sym);
436         sym_validate_range(sym);
437
438         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
439                 sym_set_changed(sym);
440                 if (modules_sym == sym) {
441                         sym_set_all_changed();
442                         modules_val = modules_sym->curr.tri;
443                 }
444         }
445
446         if (sym_is_choice(sym)) {
447                 struct symbol *choice_sym;
448
449                 prop = sym_get_choice_prop(sym);
450                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
451                         if ((sym->flags & SYMBOL_WRITE) &&
452                             choice_sym->visible != no)
453                                 choice_sym->flags |= SYMBOL_WRITE;
454                         if (sym->flags & SYMBOL_CHANGED)
455                                 sym_set_changed(choice_sym);
456                 }
457         }
458
459         if (sym->flags & SYMBOL_NO_WRITE)
460                 sym->flags &= ~SYMBOL_WRITE;
461
462         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
463                 set_all_choice_values(sym);
464 }
465
466 void sym_clear_all_valid(void)
467 {
468         struct symbol *sym;
469         int i;
470
471         for_all_symbols(i, sym)
472                 sym->flags &= ~SYMBOL_VALID;
473         conf_set_changed(true);
474         sym_calc_value(modules_sym);
475 }
476
477 bool sym_tristate_within_range(struct symbol *sym, tristate val)
478 {
479         int type = sym_get_type(sym);
480
481         if (sym->visible == no)
482                 return false;
483
484         if (type != S_BOOLEAN && type != S_TRISTATE)
485                 return false;
486
487         if (type == S_BOOLEAN && val == mod)
488                 return false;
489         if (sym->visible <= sym->rev_dep.tri)
490                 return false;
491         if (sym_is_choice_value(sym) && sym->visible == yes)
492                 return val == yes;
493         return val >= sym->rev_dep.tri && val <= sym->visible;
494 }
495
496 bool sym_set_tristate_value(struct symbol *sym, tristate val)
497 {
498         tristate oldval = sym_get_tristate_value(sym);
499
500         if (oldval != val && !sym_tristate_within_range(sym, val))
501                 return false;
502
503         if (!(sym->flags & SYMBOL_DEF_USER)) {
504                 sym->flags |= SYMBOL_DEF_USER;
505                 sym_set_changed(sym);
506         }
507         /*
508          * setting a choice value also resets the new flag of the choice
509          * symbol and all other choice values.
510          */
511         if (sym_is_choice_value(sym) && val == yes) {
512                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
513                 struct property *prop;
514                 struct expr *e;
515
516                 cs->def[S_DEF_USER].val = sym;
517                 cs->flags |= SYMBOL_DEF_USER;
518                 prop = sym_get_choice_prop(cs);
519                 for (e = prop->expr; e; e = e->left.expr) {
520                         if (e->right.sym->visible != no)
521                                 e->right.sym->flags |= SYMBOL_DEF_USER;
522                 }
523         }
524
525         sym->def[S_DEF_USER].tri = val;
526         if (oldval != val)
527                 sym_clear_all_valid();
528
529         return true;
530 }
531
532 tristate sym_toggle_tristate_value(struct symbol *sym)
533 {
534         tristate oldval, newval;
535
536         oldval = newval = sym_get_tristate_value(sym);
537         do {
538                 switch (newval) {
539                 case no:
540                         newval = mod;
541                         break;
542                 case mod:
543                         newval = yes;
544                         break;
545                 case yes:
546                         newval = no;
547                         break;
548                 }
549                 if (sym_set_tristate_value(sym, newval))
550                         break;
551         } while (oldval != newval);
552         return newval;
553 }
554
555 bool sym_string_valid(struct symbol *sym, const char *str)
556 {
557         signed char ch;
558
559         switch (sym->type) {
560         case S_STRING:
561                 return true;
562         case S_INT:
563                 ch = *str++;
564                 if (ch == '-')
565                         ch = *str++;
566                 if (!isdigit(ch))
567                         return false;
568                 if (ch == '0' && *str != 0)
569                         return false;
570                 while ((ch = *str++)) {
571                         if (!isdigit(ch))
572                                 return false;
573                 }
574                 return true;
575         case S_HEX:
576                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
577                         str += 2;
578                 ch = *str++;
579                 do {
580                         if (!isxdigit(ch))
581                                 return false;
582                 } while ((ch = *str++));
583                 return true;
584         case S_BOOLEAN:
585         case S_TRISTATE:
586                 switch (str[0]) {
587                 case 'y': case 'Y':
588                 case 'm': case 'M':
589                 case 'n': case 'N':
590                         return true;
591                 }
592                 return false;
593         default:
594                 return false;
595         }
596 }
597
598 bool sym_string_within_range(struct symbol *sym, const char *str)
599 {
600         struct property *prop;
601         long long val;
602
603         switch (sym->type) {
604         case S_STRING:
605                 return sym_string_valid(sym, str);
606         case S_INT:
607                 if (!sym_string_valid(sym, str))
608                         return false;
609                 prop = sym_get_range_prop(sym);
610                 if (!prop)
611                         return true;
612                 val = strtoll(str, NULL, 10);
613                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
614                        val <= sym_get_range_val(prop->expr->right.sym, 10);
615         case S_HEX:
616                 if (!sym_string_valid(sym, str))
617                         return false;
618                 prop = sym_get_range_prop(sym);
619                 if (!prop)
620                         return true;
621                 val = strtoll(str, NULL, 16);
622                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
623                        val <= sym_get_range_val(prop->expr->right.sym, 16);
624         case S_BOOLEAN:
625         case S_TRISTATE:
626                 switch (str[0]) {
627                 case 'y': case 'Y':
628                         return sym_tristate_within_range(sym, yes);
629                 case 'm': case 'M':
630                         return sym_tristate_within_range(sym, mod);
631                 case 'n': case 'N':
632                         return sym_tristate_within_range(sym, no);
633                 }
634                 return false;
635         default:
636                 return false;
637         }
638 }
639
640 bool sym_set_string_value(struct symbol *sym, const char *newval)
641 {
642         const char *oldval;
643         char *val;
644         int size;
645
646         switch (sym->type) {
647         case S_BOOLEAN:
648         case S_TRISTATE:
649                 switch (newval[0]) {
650                 case 'y': case 'Y':
651                         return sym_set_tristate_value(sym, yes);
652                 case 'm': case 'M':
653                         return sym_set_tristate_value(sym, mod);
654                 case 'n': case 'N':
655                         return sym_set_tristate_value(sym, no);
656                 }
657                 return false;
658         default:
659                 ;
660         }
661
662         if (!sym_string_within_range(sym, newval))
663                 return false;
664
665         if (!(sym->flags & SYMBOL_DEF_USER)) {
666                 sym->flags |= SYMBOL_DEF_USER;
667                 sym_set_changed(sym);
668         }
669
670         oldval = sym->def[S_DEF_USER].val;
671         size = strlen(newval) + 1;
672         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
673                 size += 2;
674                 sym->def[S_DEF_USER].val = val = xmalloc(size);
675                 *val++ = '0';
676                 *val++ = 'x';
677         } else if (!oldval || strcmp(oldval, newval))
678                 sym->def[S_DEF_USER].val = val = xmalloc(size);
679         else
680                 return true;
681
682         strcpy(val, newval);
683         free((void *)oldval);
684         sym_clear_all_valid();
685
686         return true;
687 }
688
689 /*
690  * Find the default value associated to a symbol.
691  * For tristate symbol handle the modules=n case
692  * in which case "m" becomes "y".
693  * If the symbol does not have any default then fallback
694  * to the fixed default values.
695  */
696 const char *sym_get_string_default(struct symbol *sym)
697 {
698         struct property *prop;
699         struct symbol *ds;
700         const char *str;
701         tristate val;
702
703         sym_calc_visibility(sym);
704         sym_calc_value(modules_sym);
705         val = symbol_no.curr.tri;
706         str = symbol_empty.curr.val;
707
708         /* If symbol has a default value look it up */
709         prop = sym_get_default_prop(sym);
710         if (prop != NULL) {
711                 switch (sym->type) {
712                 case S_BOOLEAN:
713                 case S_TRISTATE:
714                         /* The visibility may limit the value from yes => mod */
715                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
716                         break;
717                 default:
718                         /*
719                          * The following fails to handle the situation
720                          * where a default value is further limited by
721                          * the valid range.
722                          */
723                         ds = prop_get_symbol(prop);
724                         if (ds != NULL) {
725                                 sym_calc_value(ds);
726                                 str = (const char *)ds->curr.val;
727                         }
728                 }
729         }
730
731         /* Handle select statements */
732         val = EXPR_OR(val, sym->rev_dep.tri);
733
734         /* transpose mod to yes if modules are not enabled */
735         if (val == mod)
736                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
737                         val = yes;
738
739         /* transpose mod to yes if type is bool */
740         if (sym->type == S_BOOLEAN && val == mod)
741                 val = yes;
742
743         /* adjust the default value if this symbol is implied by another */
744         if (val < sym->implied.tri)
745                 val = sym->implied.tri;
746
747         switch (sym->type) {
748         case S_BOOLEAN:
749         case S_TRISTATE:
750                 switch (val) {
751                 case no: return "n";
752                 case mod: return "m";
753                 case yes: return "y";
754                 }
755         case S_INT:
756         case S_HEX:
757                 return str;
758         case S_STRING:
759                 return str;
760         case S_UNKNOWN:
761                 break;
762         }
763         return "";
764 }
765
766 const char *sym_get_string_value(struct symbol *sym)
767 {
768         tristate val;
769
770         switch (sym->type) {
771         case S_BOOLEAN:
772         case S_TRISTATE:
773                 val = sym_get_tristate_value(sym);
774                 switch (val) {
775                 case no:
776                         return "n";
777                 case mod:
778                         sym_calc_value(modules_sym);
779                         return (modules_sym->curr.tri == no) ? "n" : "m";
780                 case yes:
781                         return "y";
782                 }
783                 break;
784         default:
785                 ;
786         }
787         return (const char *)sym->curr.val;
788 }
789
790 bool sym_is_changeable(struct symbol *sym)
791 {
792         return sym->visible > sym->rev_dep.tri;
793 }
794
795 static unsigned strhash(const char *s)
796 {
797         /* fnv32 hash */
798         unsigned hash = 2166136261U;
799         for (; *s; s++)
800                 hash = (hash ^ *s) * 0x01000193;
801         return hash;
802 }
803
804 struct symbol *sym_lookup(const char *name, int flags)
805 {
806         struct symbol *symbol;
807         char *new_name;
808         int hash;
809
810         if (name) {
811                 if (name[0] && !name[1]) {
812                         switch (name[0]) {
813                         case 'y': return &symbol_yes;
814                         case 'm': return &symbol_mod;
815                         case 'n': return &symbol_no;
816                         }
817                 }
818                 hash = strhash(name) % SYMBOL_HASHSIZE;
819
820                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
821                         if (symbol->name &&
822                             !strcmp(symbol->name, name) &&
823                             (flags ? symbol->flags & flags
824                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
825                                 return symbol;
826                 }
827                 new_name = xstrdup(name);
828         } else {
829                 new_name = NULL;
830                 hash = 0;
831         }
832
833         symbol = xmalloc(sizeof(*symbol));
834         memset(symbol, 0, sizeof(*symbol));
835         symbol->name = new_name;
836         symbol->type = S_UNKNOWN;
837         symbol->flags = flags;
838
839         symbol->next = symbol_hash[hash];
840         symbol_hash[hash] = symbol;
841
842         return symbol;
843 }
844
845 struct symbol *sym_find(const char *name)
846 {
847         struct symbol *symbol = NULL;
848         int hash = 0;
849
850         if (!name)
851                 return NULL;
852
853         if (name[0] && !name[1]) {
854                 switch (name[0]) {
855                 case 'y': return &symbol_yes;
856                 case 'm': return &symbol_mod;
857                 case 'n': return &symbol_no;
858                 }
859         }
860         hash = strhash(name) % SYMBOL_HASHSIZE;
861
862         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
863                 if (symbol->name &&
864                     !strcmp(symbol->name, name) &&
865                     !(symbol->flags & SYMBOL_CONST))
866                                 break;
867         }
868
869         return symbol;
870 }
871
872 struct sym_match {
873         struct symbol   *sym;
874         off_t           so, eo;
875 };
876
877 /* Compare matched symbols as thus:
878  * - first, symbols that match exactly
879  * - then, alphabetical sort
880  */
881 static int sym_rel_comp(const void *sym1, const void *sym2)
882 {
883         const struct sym_match *s1 = sym1;
884         const struct sym_match *s2 = sym2;
885         int exact1, exact2;
886
887         /* Exact match:
888          * - if matched length on symbol s1 is the length of that symbol,
889          *   then this symbol should come first;
890          * - if matched length on symbol s2 is the length of that symbol,
891          *   then this symbol should come first.
892          * Note: since the search can be a regexp, both symbols may match
893          * exactly; if this is the case, we can't decide which comes first,
894          * and we fallback to sorting alphabetically.
895          */
896         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
897         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
898         if (exact1 && !exact2)
899                 return -1;
900         if (!exact1 && exact2)
901                 return 1;
902
903         /* As a fallback, sort symbols alphabetically */
904         return strcmp(s1->sym->name, s2->sym->name);
905 }
906
907 struct symbol **sym_re_search(const char *pattern)
908 {
909         struct symbol *sym, **sym_arr = NULL;
910         struct sym_match *sym_match_arr = NULL;
911         int i, cnt, size;
912         regex_t re;
913         regmatch_t match[1];
914
915         cnt = size = 0;
916         /* Skip if empty */
917         if (strlen(pattern) == 0)
918                 return NULL;
919         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
920                 return NULL;
921
922         for_all_symbols(i, sym) {
923                 if (sym->flags & SYMBOL_CONST || !sym->name)
924                         continue;
925                 if (regexec(&re, sym->name, 1, match, 0))
926                         continue;
927                 if (cnt >= size) {
928                         void *tmp;
929                         size += 16;
930                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
931                         if (!tmp)
932                                 goto sym_re_search_free;
933                         sym_match_arr = tmp;
934                 }
935                 sym_calc_value(sym);
936                 /* As regexec returned 0, we know we have a match, so
937                  * we can use match[0].rm_[se]o without further checks
938                  */
939                 sym_match_arr[cnt].so = match[0].rm_so;
940                 sym_match_arr[cnt].eo = match[0].rm_eo;
941                 sym_match_arr[cnt++].sym = sym;
942         }
943         if (sym_match_arr) {
944                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
945                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
946                 if (!sym_arr)
947                         goto sym_re_search_free;
948                 for (i = 0; i < cnt; i++)
949                         sym_arr[i] = sym_match_arr[i].sym;
950                 sym_arr[cnt] = NULL;
951         }
952 sym_re_search_free:
953         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
954         free(sym_match_arr);
955         regfree(&re);
956
957         return sym_arr;
958 }
959
960 /*
961  * When we check for recursive dependencies we use a stack to save
962  * current state so we can print out relevant info to user.
963  * The entries are located on the call stack so no need to free memory.
964  * Note insert() remove() must always match to properly clear the stack.
965  */
966 static struct dep_stack {
967         struct dep_stack *prev, *next;
968         struct symbol *sym;
969         struct property *prop;
970         struct expr **expr;
971 } *check_top;
972
973 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
974 {
975         memset(stack, 0, sizeof(*stack));
976         if (check_top)
977                 check_top->next = stack;
978         stack->prev = check_top;
979         stack->sym = sym;
980         check_top = stack;
981 }
982
983 static void dep_stack_remove(void)
984 {
985         check_top = check_top->prev;
986         if (check_top)
987                 check_top->next = NULL;
988 }
989
990 /*
991  * Called when we have detected a recursive dependency.
992  * check_top point to the top of the stact so we use
993  * the ->prev pointer to locate the bottom of the stack.
994  */
995 static void sym_check_print_recursive(struct symbol *last_sym)
996 {
997         struct dep_stack *stack;
998         struct symbol *sym, *next_sym;
999         struct menu *menu = NULL;
1000         struct property *prop;
1001         struct dep_stack cv_stack;
1002
1003         if (sym_is_choice_value(last_sym)) {
1004                 dep_stack_insert(&cv_stack, last_sym);
1005                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1006         }
1007
1008         for (stack = check_top; stack != NULL; stack = stack->prev)
1009                 if (stack->sym == last_sym)
1010                         break;
1011         if (!stack) {
1012                 fprintf(stderr, "unexpected recursive dependency error\n");
1013                 return;
1014         }
1015
1016         for (; stack; stack = stack->next) {
1017                 sym = stack->sym;
1018                 next_sym = stack->next ? stack->next->sym : last_sym;
1019                 prop = stack->prop;
1020                 if (prop == NULL)
1021                         prop = stack->sym->prop;
1022
1023                 /* for choice values find the menu entry (used below) */
1024                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1025                         for (prop = sym->prop; prop; prop = prop->next) {
1026                                 menu = prop->menu;
1027                                 if (prop->menu)
1028                                         break;
1029                         }
1030                 }
1031                 if (stack->sym == last_sym)
1032                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1033                                 prop->file->name, prop->lineno);
1034
1035                 if (sym_is_choice(sym)) {
1036                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1037                                 menu->file->name, menu->lineno,
1038                                 sym->name ? sym->name : "<choice>",
1039                                 next_sym->name ? next_sym->name : "<choice>");
1040                 } else if (sym_is_choice_value(sym)) {
1041                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1042                                 menu->file->name, menu->lineno,
1043                                 sym->name ? sym->name : "<choice>",
1044                                 next_sym->name ? next_sym->name : "<choice>");
1045                 } else if (stack->expr == &sym->dir_dep.expr) {
1046                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1047                                 prop->file->name, prop->lineno,
1048                                 sym->name ? sym->name : "<choice>",
1049                                 next_sym->name ? next_sym->name : "<choice>");
1050                 } else if (stack->expr == &sym->rev_dep.expr) {
1051                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1052                                 prop->file->name, prop->lineno,
1053                                 sym->name ? sym->name : "<choice>",
1054                                 next_sym->name ? next_sym->name : "<choice>");
1055                 } else if (stack->expr == &sym->implied.expr) {
1056                         fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1057                                 prop->file->name, prop->lineno,
1058                                 sym->name ? sym->name : "<choice>",
1059                                 next_sym->name ? next_sym->name : "<choice>");
1060                 } else if (stack->expr) {
1061                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1062                                 prop->file->name, prop->lineno,
1063                                 sym->name ? sym->name : "<choice>",
1064                                 prop_get_type_name(prop->type),
1065                                 next_sym->name ? next_sym->name : "<choice>");
1066                 } else {
1067                         fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1068                                 prop->file->name, prop->lineno,
1069                                 sym->name ? sym->name : "<choice>",
1070                                 prop_get_type_name(prop->type),
1071                                 next_sym->name ? next_sym->name : "<choice>");
1072                 }
1073         }
1074
1075         fprintf(stderr,
1076                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1077                 "subsection \"Kconfig recursive dependency limitations\"\n"
1078                 "\n");
1079
1080         if (check_top == &cv_stack)
1081                 dep_stack_remove();
1082 }
1083
1084 static struct symbol *sym_check_expr_deps(struct expr *e)
1085 {
1086         struct symbol *sym;
1087
1088         if (!e)
1089                 return NULL;
1090         switch (e->type) {
1091         case E_OR:
1092         case E_AND:
1093                 sym = sym_check_expr_deps(e->left.expr);
1094                 if (sym)
1095                         return sym;
1096                 return sym_check_expr_deps(e->right.expr);
1097         case E_NOT:
1098                 return sym_check_expr_deps(e->left.expr);
1099         case E_EQUAL:
1100         case E_GEQ:
1101         case E_GTH:
1102         case E_LEQ:
1103         case E_LTH:
1104         case E_UNEQUAL:
1105                 sym = sym_check_deps(e->left.sym);
1106                 if (sym)
1107                         return sym;
1108                 return sym_check_deps(e->right.sym);
1109         case E_SYMBOL:
1110                 return sym_check_deps(e->left.sym);
1111         default:
1112                 break;
1113         }
1114         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1115         return NULL;
1116 }
1117
1118 /* return NULL when dependencies are OK */
1119 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1120 {
1121         struct symbol *sym2;
1122         struct property *prop;
1123         struct dep_stack stack;
1124
1125         dep_stack_insert(&stack, sym);
1126
1127         stack.expr = &sym->dir_dep.expr;
1128         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1129         if (sym2)
1130                 goto out;
1131
1132         stack.expr = &sym->rev_dep.expr;
1133         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1134         if (sym2)
1135                 goto out;
1136
1137         stack.expr = &sym->implied.expr;
1138         sym2 = sym_check_expr_deps(sym->implied.expr);
1139         if (sym2)
1140                 goto out;
1141
1142         stack.expr = NULL;
1143
1144         for (prop = sym->prop; prop; prop = prop->next) {
1145                 if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1146                     prop->type == P_IMPLY)
1147                         continue;
1148                 stack.prop = prop;
1149                 sym2 = sym_check_expr_deps(prop->visible.expr);
1150                 if (sym2)
1151                         break;
1152                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1153                         continue;
1154                 stack.expr = &prop->expr;
1155                 sym2 = sym_check_expr_deps(prop->expr);
1156                 if (sym2)
1157                         break;
1158                 stack.expr = NULL;
1159         }
1160
1161 out:
1162         dep_stack_remove();
1163
1164         return sym2;
1165 }
1166
1167 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1168 {
1169         struct symbol *sym, *sym2;
1170         struct property *prop;
1171         struct expr *e;
1172         struct dep_stack stack;
1173
1174         dep_stack_insert(&stack, choice);
1175
1176         prop = sym_get_choice_prop(choice);
1177         expr_list_for_each_sym(prop->expr, e, sym)
1178                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1179
1180         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1181         sym2 = sym_check_sym_deps(choice);
1182         choice->flags &= ~SYMBOL_CHECK;
1183         if (sym2)
1184                 goto out;
1185
1186         expr_list_for_each_sym(prop->expr, e, sym) {
1187                 sym2 = sym_check_sym_deps(sym);
1188                 if (sym2)
1189                         break;
1190         }
1191 out:
1192         expr_list_for_each_sym(prop->expr, e, sym)
1193                 sym->flags &= ~SYMBOL_CHECK;
1194
1195         if (sym2 && sym_is_choice_value(sym2) &&
1196             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1197                 sym2 = choice;
1198
1199         dep_stack_remove();
1200
1201         return sym2;
1202 }
1203
1204 struct symbol *sym_check_deps(struct symbol *sym)
1205 {
1206         struct symbol *sym2;
1207         struct property *prop;
1208
1209         if (sym->flags & SYMBOL_CHECK) {
1210                 sym_check_print_recursive(sym);
1211                 return sym;
1212         }
1213         if (sym->flags & SYMBOL_CHECKED)
1214                 return NULL;
1215
1216         if (sym_is_choice_value(sym)) {
1217                 struct dep_stack stack;
1218
1219                 /* for choice groups start the check with main choice symbol */
1220                 dep_stack_insert(&stack, sym);
1221                 prop = sym_get_choice_prop(sym);
1222                 sym2 = sym_check_deps(prop_get_symbol(prop));
1223                 dep_stack_remove();
1224         } else if (sym_is_choice(sym)) {
1225                 sym2 = sym_check_choice_deps(sym);
1226         } else {
1227                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1228                 sym2 = sym_check_sym_deps(sym);
1229                 sym->flags &= ~SYMBOL_CHECK;
1230         }
1231
1232         return sym2;
1233 }
1234
1235 struct symbol *prop_get_symbol(struct property *prop)
1236 {
1237         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1238                            prop->expr->type == E_LIST))
1239                 return prop->expr->left.sym;
1240         return NULL;
1241 }
1242
1243 const char *prop_get_type_name(enum prop_type type)
1244 {
1245         switch (type) {
1246         case P_PROMPT:
1247                 return "prompt";
1248         case P_COMMENT:
1249                 return "comment";
1250         case P_MENU:
1251                 return "menu";
1252         case P_DEFAULT:
1253                 return "default";
1254         case P_CHOICE:
1255                 return "choice";
1256         case P_SELECT:
1257                 return "select";
1258         case P_IMPLY:
1259                 return "imply";
1260         case P_RANGE:
1261                 return "range";
1262         case P_SYMBOL:
1263                 return "symbol";
1264         case P_UNKNOWN:
1265                 break;
1266         }
1267         return "unknown";
1268 }