kconfig: split out useful helpers in confdata.c
[carl9170fw.git] / config / symbol.c
1 /*
2  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
3  * Released under the terms of the GNU GPL v2.0.
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         case S_OTHER:
65                 break;
66         }
67         return "???";
68 }
69
70 struct property *sym_get_choice_prop(struct symbol *sym)
71 {
72         struct property *prop;
73
74         for_all_choices(sym, prop)
75                 return prop;
76         return NULL;
77 }
78
79 struct property *sym_get_env_prop(struct symbol *sym)
80 {
81         struct property *prop;
82
83         for_all_properties(sym, prop, P_ENV)
84                 return prop;
85         return NULL;
86 }
87
88 static struct property *sym_get_default_prop(struct symbol *sym)
89 {
90         struct property *prop;
91
92         for_all_defaults(sym, prop) {
93                 prop->visible.tri = expr_calc_value(prop->visible.expr);
94                 if (prop->visible.tri != no)
95                         return prop;
96         }
97         return NULL;
98 }
99
100 static struct property *sym_get_range_prop(struct symbol *sym)
101 {
102         struct property *prop;
103
104         for_all_properties(sym, prop, P_RANGE) {
105                 prop->visible.tri = expr_calc_value(prop->visible.expr);
106                 if (prop->visible.tri != no)
107                         return prop;
108         }
109         return NULL;
110 }
111
112 static long long sym_get_range_val(struct symbol *sym, int base)
113 {
114         sym_calc_value(sym);
115         switch (sym->type) {
116         case S_INT:
117                 base = 10;
118                 break;
119         case S_HEX:
120                 base = 16;
121                 break;
122         default:
123                 break;
124         }
125         return strtoll(sym->curr.val, NULL, base);
126 }
127
128 static void sym_validate_range(struct symbol *sym)
129 {
130         struct property *prop;
131         int base;
132         long long val, val2;
133         char str[64];
134
135         switch (sym->type) {
136         case S_INT:
137                 base = 10;
138                 break;
139         case S_HEX:
140                 base = 16;
141                 break;
142         default:
143                 return;
144         }
145         prop = sym_get_range_prop(sym);
146         if (!prop)
147                 return;
148         val = strtoll(sym->curr.val, NULL, base);
149         val2 = sym_get_range_val(prop->expr->left.sym, base);
150         if (val >= val2) {
151                 val2 = sym_get_range_val(prop->expr->right.sym, base);
152                 if (val <= val2)
153                         return;
154         }
155         if (sym->type == S_INT)
156                 sprintf(str, "%lld", val2);
157         else
158                 sprintf(str, "0x%llx", val2);
159         sym->curr.val = xstrdup(str);
160 }
161
162 static void sym_set_changed(struct symbol *sym)
163 {
164         struct property *prop;
165
166         sym->flags |= SYMBOL_CHANGED;
167         for (prop = sym->prop; prop; prop = prop->next) {
168                 if (prop->menu)
169                         prop->menu->flags |= MENU_CHANGED;
170         }
171 }
172
173 static void sym_set_all_changed(void)
174 {
175         struct symbol *sym;
176         int i;
177
178         for_all_symbols(i, sym)
179                 sym_set_changed(sym);
180 }
181
182 static void sym_calc_visibility(struct symbol *sym)
183 {
184         struct property *prop;
185         struct symbol *choice_sym = NULL;
186         tristate tri;
187
188         /* any prompt visible? */
189         tri = no;
190
191         if (sym_is_choice_value(sym))
192                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
193
194         for_all_prompts(sym, prop) {
195                 prop->visible.tri = expr_calc_value(prop->visible.expr);
196                 /*
197                  * Tristate choice_values with visibility 'mod' are
198                  * not visible if the corresponding choice's value is
199                  * 'yes'.
200                  */
201                 if (choice_sym && sym->type == S_TRISTATE &&
202                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
203                         prop->visible.tri = no;
204
205                 tri = EXPR_OR(tri, prop->visible.tri);
206         }
207         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
208                 tri = yes;
209         if (sym->visible != tri) {
210                 sym->visible = tri;
211                 sym_set_changed(sym);
212         }
213         if (sym_is_choice_value(sym))
214                 return;
215         /* defaulting to "yes" if no explicit "depends on" are given */
216         tri = yes;
217         if (sym->dir_dep.expr)
218                 tri = expr_calc_value(sym->dir_dep.expr);
219         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
220                 tri = yes;
221         if (sym->dir_dep.tri != tri) {
222                 sym->dir_dep.tri = tri;
223                 sym_set_changed(sym);
224         }
225         tri = no;
226         if (sym->rev_dep.expr)
227                 tri = expr_calc_value(sym->rev_dep.expr);
228         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
229                 tri = yes;
230         if (sym->rev_dep.tri != tri) {
231                 sym->rev_dep.tri = tri;
232                 sym_set_changed(sym);
233         }
234         tri = no;
235         if (sym->implied.expr && sym->dir_dep.tri != no)
236                 tri = expr_calc_value(sym->implied.expr);
237         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
238                 tri = yes;
239         if (sym->implied.tri != tri) {
240                 sym->implied.tri = tri;
241                 sym_set_changed(sym);
242         }
243 }
244
245 /*
246  * Find the default symbol for a choice.
247  * First try the default values for the choice symbol
248  * Next locate the first visible choice value
249  * Return NULL if none was found
250  */
251 struct symbol *sym_choice_default(struct symbol *sym)
252 {
253         struct symbol *def_sym;
254         struct property *prop;
255         struct expr *e;
256
257         /* any of the defaults visible? */
258         for_all_defaults(sym, prop) {
259                 prop->visible.tri = expr_calc_value(prop->visible.expr);
260                 if (prop->visible.tri == no)
261                         continue;
262                 def_sym = prop_get_symbol(prop);
263                 if (def_sym->visible != no)
264                         return def_sym;
265         }
266
267         /* just get the first visible value */
268         prop = sym_get_choice_prop(sym);
269         expr_list_for_each_sym(prop->expr, e, def_sym)
270                 if (def_sym->visible != no)
271                         return def_sym;
272
273         /* failed to locate any defaults */
274         return NULL;
275 }
276
277 static struct symbol *sym_calc_choice(struct symbol *sym)
278 {
279         struct symbol *def_sym;
280         struct property *prop;
281         struct expr *e;
282         int flags;
283
284         /* first calculate all choice values' visibilities */
285         flags = sym->flags;
286         prop = sym_get_choice_prop(sym);
287         expr_list_for_each_sym(prop->expr, e, def_sym) {
288                 sym_calc_visibility(def_sym);
289                 if (def_sym->visible != no)
290                         flags &= def_sym->flags;
291         }
292
293         sym->flags &= flags | ~SYMBOL_DEF_USER;
294
295         /* is the user choice visible? */
296         def_sym = sym->def[S_DEF_USER].val;
297         if (def_sym && def_sym->visible != no)
298                 return def_sym;
299
300         def_sym = sym_choice_default(sym);
301
302         if (def_sym == NULL)
303                 /* no choice? reset tristate value */
304                 sym->curr.tri = no;
305
306         return def_sym;
307 }
308
309 static void sym_warn_unmet_dep(struct symbol *sym)
310 {
311         struct gstr gs = str_new();
312
313         str_printf(&gs,
314                    "\nWARNING: unmet direct dependencies detected for %s\n",
315                    sym->name);
316         str_printf(&gs,
317                    "  Depends on [%c]: ",
318                    sym->dir_dep.tri == mod ? 'm' : 'n');
319         expr_gstr_print(sym->dir_dep.expr, &gs);
320         str_printf(&gs, "\n");
321
322         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
323                                "  Selected by [y]:\n");
324         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
325                                "  Selected by [m]:\n");
326
327         fputs(str_get(&gs), stderr);
328 }
329
330 void sym_calc_value(struct symbol *sym)
331 {
332         struct symbol_value newval, oldval;
333         struct property *prop;
334         struct expr *e;
335
336         if (!sym)
337                 return;
338
339         if (sym->flags & SYMBOL_VALID)
340                 return;
341
342         if (sym_is_choice_value(sym) &&
343             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
344                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
345                 prop = sym_get_choice_prop(sym);
346                 sym_calc_value(prop_get_symbol(prop));
347         }
348
349         sym->flags |= SYMBOL_VALID;
350
351         oldval = sym->curr;
352
353         switch (sym->type) {
354         case S_INT:
355         case S_HEX:
356         case S_STRING:
357                 newval = symbol_empty.curr;
358                 break;
359         case S_BOOLEAN:
360         case S_TRISTATE:
361                 newval = symbol_no.curr;
362                 break;
363         default:
364                 sym->curr.val = sym->name;
365                 sym->curr.tri = no;
366                 return;
367         }
368         sym->flags &= ~SYMBOL_WRITE;
369
370         sym_calc_visibility(sym);
371
372         if (sym->visible != no)
373                 sym->flags |= SYMBOL_WRITE;
374
375         /* set default if recursively called */
376         sym->curr = newval;
377
378         switch (sym_get_type(sym)) {
379         case S_BOOLEAN:
380         case S_TRISTATE:
381                 if (sym_is_choice_value(sym) && sym->visible == yes) {
382                         prop = sym_get_choice_prop(sym);
383                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
384                 } else {
385                         if (sym->visible != no) {
386                                 /* if the symbol is visible use the user value
387                                  * if available, otherwise try the default value
388                                  */
389                                 if (sym_has_value(sym)) {
390                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
391                                                               sym->visible);
392                                         goto calc_newval;
393                                 }
394                         }
395                         if (sym->rev_dep.tri != no)
396                                 sym->flags |= SYMBOL_WRITE;
397                         if (!sym_is_choice(sym)) {
398                                 prop = sym_get_default_prop(sym);
399                                 if (prop) {
400                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
401                                                               prop->visible.tri);
402                                         if (newval.tri != no)
403                                                 sym->flags |= SYMBOL_WRITE;
404                                 }
405                                 if (sym->implied.tri != no) {
406                                         sym->flags |= SYMBOL_WRITE;
407                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
408                                 }
409                         }
410                 calc_newval:
411                         if (sym->dir_dep.tri < sym->rev_dep.tri)
412                                 sym_warn_unmet_dep(sym);
413                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
414                 }
415                 if (newval.tri == mod &&
416                     (sym_get_type(sym) == S_BOOLEAN || sym->implied.tri == yes))
417                         newval.tri = yes;
418                 break;
419         case S_STRING:
420         case S_HEX:
421         case S_INT:
422                 if (sym->visible != no && sym_has_value(sym)) {
423                         newval.val = sym->def[S_DEF_USER].val;
424                         break;
425                 }
426                 prop = sym_get_default_prop(sym);
427                 if (prop) {
428                         struct symbol *ds = prop_get_symbol(prop);
429                         if (ds) {
430                                 sym->flags |= SYMBOL_WRITE;
431                                 sym_calc_value(ds);
432                                 newval.val = ds->curr.val;
433                         }
434                 }
435                 break;
436         default:
437                 ;
438         }
439
440         sym->curr = newval;
441         if (sym_is_choice(sym) && newval.tri == yes)
442                 sym->curr.val = sym_calc_choice(sym);
443         sym_validate_range(sym);
444
445         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
446                 sym_set_changed(sym);
447                 if (modules_sym == sym) {
448                         sym_set_all_changed();
449                         modules_val = modules_sym->curr.tri;
450                 }
451         }
452
453         if (sym_is_choice(sym)) {
454                 struct symbol *choice_sym;
455
456                 prop = sym_get_choice_prop(sym);
457                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
458                         if ((sym->flags & SYMBOL_WRITE) &&
459                             choice_sym->visible != no)
460                                 choice_sym->flags |= SYMBOL_WRITE;
461                         if (sym->flags & SYMBOL_CHANGED)
462                                 sym_set_changed(choice_sym);
463                 }
464         }
465
466         if (sym->flags & SYMBOL_NO_WRITE)
467                 sym->flags &= ~SYMBOL_WRITE;
468
469         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
470                 set_all_choice_values(sym);
471 }
472
473 void sym_clear_all_valid(void)
474 {
475         struct symbol *sym;
476         int i;
477
478         for_all_symbols(i, sym)
479                 sym->flags &= ~SYMBOL_VALID;
480         sym_add_change_count(1);
481         sym_calc_value(modules_sym);
482 }
483
484 bool sym_tristate_within_range(struct symbol *sym, tristate val)
485 {
486         int type = sym_get_type(sym);
487
488         if (sym->visible == no)
489                 return false;
490
491         if (type != S_BOOLEAN && type != S_TRISTATE)
492                 return false;
493
494         if (type == S_BOOLEAN && val == mod)
495                 return false;
496         if (sym->visible <= sym->rev_dep.tri)
497                 return false;
498         if (sym->implied.tri == yes && val == mod)
499                 return false;
500         if (sym_is_choice_value(sym) && sym->visible == yes)
501                 return val == yes;
502         return val >= sym->rev_dep.tri && val <= sym->visible;
503 }
504
505 bool sym_set_tristate_value(struct symbol *sym, tristate val)
506 {
507         tristate oldval = sym_get_tristate_value(sym);
508
509         if (oldval != val && !sym_tristate_within_range(sym, val))
510                 return false;
511
512         if (!(sym->flags & SYMBOL_DEF_USER)) {
513                 sym->flags |= SYMBOL_DEF_USER;
514                 sym_set_changed(sym);
515         }
516         /*
517          * setting a choice value also resets the new flag of the choice
518          * symbol and all other choice values.
519          */
520         if (sym_is_choice_value(sym) && val == yes) {
521                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
522                 struct property *prop;
523                 struct expr *e;
524
525                 cs->def[S_DEF_USER].val = sym;
526                 cs->flags |= SYMBOL_DEF_USER;
527                 prop = sym_get_choice_prop(cs);
528                 for (e = prop->expr; e; e = e->left.expr) {
529                         if (e->right.sym->visible != no)
530                                 e->right.sym->flags |= SYMBOL_DEF_USER;
531                 }
532         }
533
534         sym->def[S_DEF_USER].tri = val;
535         if (oldval != val)
536                 sym_clear_all_valid();
537
538         return true;
539 }
540
541 tristate sym_toggle_tristate_value(struct symbol *sym)
542 {
543         tristate oldval, newval;
544
545         oldval = newval = sym_get_tristate_value(sym);
546         do {
547                 switch (newval) {
548                 case no:
549                         newval = mod;
550                         break;
551                 case mod:
552                         newval = yes;
553                         break;
554                 case yes:
555                         newval = no;
556                         break;
557                 }
558                 if (sym_set_tristate_value(sym, newval))
559                         break;
560         } while (oldval != newval);
561         return newval;
562 }
563
564 bool sym_string_valid(struct symbol *sym, const char *str)
565 {
566         signed char ch;
567
568         switch (sym->type) {
569         case S_STRING:
570                 return true;
571         case S_INT:
572                 ch = *str++;
573                 if (ch == '-')
574                         ch = *str++;
575                 if (!isdigit(ch))
576                         return false;
577                 if (ch == '0' && *str != 0)
578                         return false;
579                 while ((ch = *str++)) {
580                         if (!isdigit(ch))
581                                 return false;
582                 }
583                 return true;
584         case S_HEX:
585                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
586                         str += 2;
587                 ch = *str++;
588                 do {
589                         if (!isxdigit(ch))
590                                 return false;
591                 } while ((ch = *str++));
592                 return true;
593         case S_BOOLEAN:
594         case S_TRISTATE:
595                 switch (str[0]) {
596                 case 'y': case 'Y':
597                 case 'm': case 'M':
598                 case 'n': case 'N':
599                         return true;
600                 }
601                 return false;
602         default:
603                 return false;
604         }
605 }
606
607 bool sym_string_within_range(struct symbol *sym, const char *str)
608 {
609         struct property *prop;
610         long long val;
611
612         switch (sym->type) {
613         case S_STRING:
614                 return sym_string_valid(sym, str);
615         case S_INT:
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, 10);
622                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
623                        val <= sym_get_range_val(prop->expr->right.sym, 10);
624         case S_HEX:
625                 if (!sym_string_valid(sym, str))
626                         return false;
627                 prop = sym_get_range_prop(sym);
628                 if (!prop)
629                         return true;
630                 val = strtoll(str, NULL, 16);
631                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
632                        val <= sym_get_range_val(prop->expr->right.sym, 16);
633         case S_BOOLEAN:
634         case S_TRISTATE:
635                 switch (str[0]) {
636                 case 'y': case 'Y':
637                         return sym_tristate_within_range(sym, yes);
638                 case 'm': case 'M':
639                         return sym_tristate_within_range(sym, mod);
640                 case 'n': case 'N':
641                         return sym_tristate_within_range(sym, no);
642                 }
643                 return false;
644         default:
645                 return false;
646         }
647 }
648
649 bool sym_set_string_value(struct symbol *sym, const char *newval)
650 {
651         const char *oldval;
652         char *val;
653         int size;
654
655         switch (sym->type) {
656         case S_BOOLEAN:
657         case S_TRISTATE:
658                 switch (newval[0]) {
659                 case 'y': case 'Y':
660                         return sym_set_tristate_value(sym, yes);
661                 case 'm': case 'M':
662                         return sym_set_tristate_value(sym, mod);
663                 case 'n': case 'N':
664                         return sym_set_tristate_value(sym, no);
665                 }
666                 return false;
667         default:
668                 ;
669         }
670
671         if (!sym_string_within_range(sym, newval))
672                 return false;
673
674         if (!(sym->flags & SYMBOL_DEF_USER)) {
675                 sym->flags |= SYMBOL_DEF_USER;
676                 sym_set_changed(sym);
677         }
678
679         oldval = sym->def[S_DEF_USER].val;
680         size = strlen(newval) + 1;
681         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
682                 size += 2;
683                 sym->def[S_DEF_USER].val = val = xmalloc(size);
684                 *val++ = '0';
685                 *val++ = 'x';
686         } else if (!oldval || strcmp(oldval, newval))
687                 sym->def[S_DEF_USER].val = val = xmalloc(size);
688         else
689                 return true;
690
691         strcpy(val, newval);
692         free((void *)oldval);
693         sym_clear_all_valid();
694
695         return true;
696 }
697
698 /*
699  * Find the default value associated to a symbol.
700  * For tristate symbol handle the modules=n case
701  * in which case "m" becomes "y".
702  * If the symbol does not have any default then fallback
703  * to the fixed default values.
704  */
705 const char *sym_get_string_default(struct symbol *sym)
706 {
707         struct property *prop;
708         struct symbol *ds;
709         const char *str;
710         tristate val;
711
712         sym_calc_visibility(sym);
713         sym_calc_value(modules_sym);
714         val = symbol_no.curr.tri;
715         str = symbol_empty.curr.val;
716
717         /* If symbol has a default value look it up */
718         prop = sym_get_default_prop(sym);
719         if (prop != NULL) {
720                 switch (sym->type) {
721                 case S_BOOLEAN:
722                 case S_TRISTATE:
723                         /* The visibility may limit the value from yes => mod */
724                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
725                         break;
726                 default:
727                         /*
728                          * The following fails to handle the situation
729                          * where a default value is further limited by
730                          * the valid range.
731                          */
732                         ds = prop_get_symbol(prop);
733                         if (ds != NULL) {
734                                 sym_calc_value(ds);
735                                 str = (const char *)ds->curr.val;
736                         }
737                 }
738         }
739
740         /* Handle select statements */
741         val = EXPR_OR(val, sym->rev_dep.tri);
742
743         /* transpose mod to yes if modules are not enabled */
744         if (val == mod)
745                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
746                         val = yes;
747
748         /* transpose mod to yes if type is bool */
749         if (sym->type == S_BOOLEAN && val == mod)
750                 val = yes;
751
752         /* adjust the default value if this symbol is implied by another */
753         if (val < sym->implied.tri)
754                 val = sym->implied.tri;
755
756         switch (sym->type) {
757         case S_BOOLEAN:
758         case S_TRISTATE:
759                 switch (val) {
760                 case no: return "n";
761                 case mod: return "m";
762                 case yes: return "y";
763                 }
764         case S_INT:
765         case S_HEX:
766                 return str;
767         case S_STRING:
768                 return str;
769         case S_OTHER:
770         case S_UNKNOWN:
771                 break;
772         }
773         return "";
774 }
775
776 const char *sym_get_string_value(struct symbol *sym)
777 {
778         tristate val;
779
780         switch (sym->type) {
781         case S_BOOLEAN:
782         case S_TRISTATE:
783                 val = sym_get_tristate_value(sym);
784                 switch (val) {
785                 case no:
786                         return "n";
787                 case mod:
788                         sym_calc_value(modules_sym);
789                         return (modules_sym->curr.tri == no) ? "n" : "m";
790                 case yes:
791                         return "y";
792                 }
793                 break;
794         default:
795                 ;
796         }
797         return (const char *)sym->curr.val;
798 }
799
800 bool sym_is_changable(struct symbol *sym)
801 {
802         return sym->visible > sym->rev_dep.tri;
803 }
804
805 static unsigned strhash(const char *s)
806 {
807         /* fnv32 hash */
808         unsigned hash = 2166136261U;
809         for (; *s; s++)
810                 hash = (hash ^ *s) * 0x01000193;
811         return hash;
812 }
813
814 struct symbol *sym_lookup(const char *name, int flags)
815 {
816         struct symbol *symbol;
817         char *new_name;
818         int hash;
819
820         if (name) {
821                 if (name[0] && !name[1]) {
822                         switch (name[0]) {
823                         case 'y': return &symbol_yes;
824                         case 'm': return &symbol_mod;
825                         case 'n': return &symbol_no;
826                         }
827                 }
828                 hash = strhash(name) % SYMBOL_HASHSIZE;
829
830                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
831                         if (symbol->name &&
832                             !strcmp(symbol->name, name) &&
833                             (flags ? symbol->flags & flags
834                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
835                                 return symbol;
836                 }
837                 new_name = xstrdup(name);
838         } else {
839                 new_name = NULL;
840                 hash = 0;
841         }
842
843         symbol = xmalloc(sizeof(*symbol));
844         memset(symbol, 0, sizeof(*symbol));
845         symbol->name = new_name;
846         symbol->type = S_UNKNOWN;
847         symbol->flags |= flags;
848
849         symbol->next = symbol_hash[hash];
850         symbol_hash[hash] = symbol;
851
852         return symbol;
853 }
854
855 struct symbol *sym_find(const char *name)
856 {
857         struct symbol *symbol = NULL;
858         int hash = 0;
859
860         if (!name)
861                 return NULL;
862
863         if (name[0] && !name[1]) {
864                 switch (name[0]) {
865                 case 'y': return &symbol_yes;
866                 case 'm': return &symbol_mod;
867                 case 'n': return &symbol_no;
868                 }
869         }
870         hash = strhash(name) % SYMBOL_HASHSIZE;
871
872         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
873                 if (symbol->name &&
874                     !strcmp(symbol->name, name) &&
875                     !(symbol->flags & SYMBOL_CONST))
876                                 break;
877         }
878
879         return symbol;
880 }
881
882 const char *sym_escape_string_value(const char *in)
883 {
884         const char *p;
885         size_t reslen;
886         char *res;
887         size_t l;
888
889         reslen = strlen(in) + strlen("\"\"") + 1;
890
891         p = in;
892         for (;;) {
893                 l = strcspn(p, "\"\\");
894                 p += l;
895
896                 if (p[0] == '\0')
897                         break;
898
899                 reslen++;
900                 p++;
901         }
902
903         res = xmalloc(reslen);
904         res[0] = '\0';
905
906         strcat(res, "\"");
907
908         p = in;
909         for (;;) {
910                 l = strcspn(p, "\"\\");
911                 strncat(res, p, l);
912                 p += l;
913
914                 if (p[0] == '\0')
915                         break;
916
917                 strcat(res, "\\");
918                 strncat(res, p++, 1);
919         }
920
921         strcat(res, "\"");
922         return res;
923 }
924
925 struct sym_match {
926         struct symbol   *sym;
927         off_t           so, eo;
928 };
929
930 /* Compare matched symbols as thus:
931  * - first, symbols that match exactly
932  * - then, alphabetical sort
933  */
934 static int sym_rel_comp(const void *sym1, const void *sym2)
935 {
936         const struct sym_match *s1 = sym1;
937         const struct sym_match *s2 = sym2;
938         int exact1, exact2;
939
940         /* Exact match:
941          * - if matched length on symbol s1 is the length of that symbol,
942          *   then this symbol should come first;
943          * - if matched length on symbol s2 is the length of that symbol,
944          *   then this symbol should come first.
945          * Note: since the search can be a regexp, both symbols may match
946          * exactly; if this is the case, we can't decide which comes first,
947          * and we fallback to sorting alphabetically.
948          */
949         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
950         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
951         if (exact1 && !exact2)
952                 return -1;
953         if (!exact1 && exact2)
954                 return 1;
955
956         /* As a fallback, sort symbols alphabetically */
957         return strcmp(s1->sym->name, s2->sym->name);
958 }
959
960 struct symbol **sym_re_search(const char *pattern)
961 {
962         struct symbol *sym, **sym_arr = NULL;
963         struct sym_match *sym_match_arr = NULL;
964         int i, cnt, size;
965         regex_t re;
966         regmatch_t match[1];
967
968         cnt = size = 0;
969         /* Skip if empty */
970         if (strlen(pattern) == 0)
971                 return NULL;
972         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
973                 return NULL;
974
975         for_all_symbols(i, sym) {
976                 if (sym->flags & SYMBOL_CONST || !sym->name)
977                         continue;
978                 if (regexec(&re, sym->name, 1, match, 0))
979                         continue;
980                 if (cnt >= size) {
981                         void *tmp;
982                         size += 16;
983                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
984                         if (!tmp)
985                                 goto sym_re_search_free;
986                         sym_match_arr = tmp;
987                 }
988                 sym_calc_value(sym);
989                 /* As regexec returned 0, we know we have a match, so
990                  * we can use match[0].rm_[se]o without further checks
991                  */
992                 sym_match_arr[cnt].so = match[0].rm_so;
993                 sym_match_arr[cnt].eo = match[0].rm_eo;
994                 sym_match_arr[cnt++].sym = sym;
995         }
996         if (sym_match_arr) {
997                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
998                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
999                 if (!sym_arr)
1000                         goto sym_re_search_free;
1001                 for (i = 0; i < cnt; i++)
1002                         sym_arr[i] = sym_match_arr[i].sym;
1003                 sym_arr[cnt] = NULL;
1004         }
1005 sym_re_search_free:
1006         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1007         free(sym_match_arr);
1008         regfree(&re);
1009
1010         return sym_arr;
1011 }
1012
1013 /*
1014  * When we check for recursive dependencies we use a stack to save
1015  * current state so we can print out relevant info to user.
1016  * The entries are located on the call stack so no need to free memory.
1017  * Note insert() remove() must always match to properly clear the stack.
1018  */
1019 static struct dep_stack {
1020         struct dep_stack *prev, *next;
1021         struct symbol *sym;
1022         struct property *prop;
1023         struct expr *expr;
1024 } *check_top;
1025
1026 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1027 {
1028         memset(stack, 0, sizeof(*stack));
1029         if (check_top)
1030                 check_top->next = stack;
1031         stack->prev = check_top;
1032         stack->sym = sym;
1033         check_top = stack;
1034 }
1035
1036 static void dep_stack_remove(void)
1037 {
1038         check_top = check_top->prev;
1039         if (check_top)
1040                 check_top->next = NULL;
1041 }
1042
1043 /*
1044  * Called when we have detected a recursive dependency.
1045  * check_top point to the top of the stact so we use
1046  * the ->prev pointer to locate the bottom of the stack.
1047  */
1048 static void sym_check_print_recursive(struct symbol *last_sym)
1049 {
1050         struct dep_stack *stack;
1051         struct symbol *sym, *next_sym;
1052         struct menu *menu = NULL;
1053         struct property *prop;
1054         struct dep_stack cv_stack;
1055
1056         if (sym_is_choice_value(last_sym)) {
1057                 dep_stack_insert(&cv_stack, last_sym);
1058                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1059         }
1060
1061         for (stack = check_top; stack != NULL; stack = stack->prev)
1062                 if (stack->sym == last_sym)
1063                         break;
1064         if (!stack) {
1065                 fprintf(stderr, "unexpected recursive dependency error\n");
1066                 return;
1067         }
1068
1069         for (; stack; stack = stack->next) {
1070                 sym = stack->sym;
1071                 next_sym = stack->next ? stack->next->sym : last_sym;
1072                 prop = stack->prop;
1073                 if (prop == NULL)
1074                         prop = stack->sym->prop;
1075
1076                 /* for choice values find the menu entry (used below) */
1077                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1078                         for (prop = sym->prop; prop; prop = prop->next) {
1079                                 menu = prop->menu;
1080                                 if (prop->menu)
1081                                         break;
1082                         }
1083                 }
1084                 if (stack->sym == last_sym)
1085                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1086                                 prop->file->name, prop->lineno);
1087
1088                 if (stack->expr) {
1089                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1090                                 prop->file->name, prop->lineno,
1091                                 sym->name ? sym->name : "<choice>",
1092                                 prop_get_type_name(prop->type),
1093                                 next_sym->name ? next_sym->name : "<choice>");
1094                 } else if (stack->prop) {
1095                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1096                                 prop->file->name, prop->lineno,
1097                                 sym->name ? sym->name : "<choice>",
1098                                 next_sym->name ? next_sym->name : "<choice>");
1099                 } else if (sym_is_choice(sym)) {
1100                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1101                                 menu->file->name, menu->lineno,
1102                                 sym->name ? sym->name : "<choice>",
1103                                 next_sym->name ? next_sym->name : "<choice>");
1104                 } else if (sym_is_choice_value(sym)) {
1105                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1106                                 menu->file->name, menu->lineno,
1107                                 sym->name ? sym->name : "<choice>",
1108                                 next_sym->name ? next_sym->name : "<choice>");
1109                 } else {
1110                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1111                                 prop->file->name, prop->lineno,
1112                                 sym->name ? sym->name : "<choice>",
1113                                 next_sym->name ? next_sym->name : "<choice>");
1114                 }
1115         }
1116
1117         fprintf(stderr,
1118                 "For a resolution refer to Documentation/kbuild/kconfig-language.txt\n"
1119                 "subsection \"Kconfig recursive dependency limitations\"\n"
1120                 "\n");
1121
1122         if (check_top == &cv_stack)
1123                 dep_stack_remove();
1124 }
1125
1126 static struct symbol *sym_check_expr_deps(struct expr *e)
1127 {
1128         struct symbol *sym;
1129
1130         if (!e)
1131                 return NULL;
1132         switch (e->type) {
1133         case E_OR:
1134         case E_AND:
1135                 sym = sym_check_expr_deps(e->left.expr);
1136                 if (sym)
1137                         return sym;
1138                 return sym_check_expr_deps(e->right.expr);
1139         case E_NOT:
1140                 return sym_check_expr_deps(e->left.expr);
1141         case E_EQUAL:
1142         case E_GEQ:
1143         case E_GTH:
1144         case E_LEQ:
1145         case E_LTH:
1146         case E_UNEQUAL:
1147                 sym = sym_check_deps(e->left.sym);
1148                 if (sym)
1149                         return sym;
1150                 return sym_check_deps(e->right.sym);
1151         case E_SYMBOL:
1152                 return sym_check_deps(e->left.sym);
1153         default:
1154                 break;
1155         }
1156         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1157         return NULL;
1158 }
1159
1160 /* return NULL when dependencies are OK */
1161 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1162 {
1163         struct symbol *sym2;
1164         struct property *prop;
1165         struct dep_stack stack;
1166
1167         dep_stack_insert(&stack, sym);
1168
1169         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1170         if (sym2)
1171                 goto out;
1172
1173         for (prop = sym->prop; prop; prop = prop->next) {
1174                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1175                         continue;
1176                 stack.prop = prop;
1177                 sym2 = sym_check_expr_deps(prop->visible.expr);
1178                 if (sym2)
1179                         break;
1180                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1181                         continue;
1182                 stack.expr = prop->expr;
1183                 sym2 = sym_check_expr_deps(prop->expr);
1184                 if (sym2)
1185                         break;
1186                 stack.expr = NULL;
1187         }
1188
1189 out:
1190         dep_stack_remove();
1191
1192         return sym2;
1193 }
1194
1195 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1196 {
1197         struct symbol *sym, *sym2;
1198         struct property *prop;
1199         struct expr *e;
1200         struct dep_stack stack;
1201
1202         dep_stack_insert(&stack, choice);
1203
1204         prop = sym_get_choice_prop(choice);
1205         expr_list_for_each_sym(prop->expr, e, sym)
1206                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1207
1208         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1209         sym2 = sym_check_sym_deps(choice);
1210         choice->flags &= ~SYMBOL_CHECK;
1211         if (sym2)
1212                 goto out;
1213
1214         expr_list_for_each_sym(prop->expr, e, sym) {
1215                 sym2 = sym_check_sym_deps(sym);
1216                 if (sym2)
1217                         break;
1218         }
1219 out:
1220         expr_list_for_each_sym(prop->expr, e, sym)
1221                 sym->flags &= ~SYMBOL_CHECK;
1222
1223         if (sym2 && sym_is_choice_value(sym2) &&
1224             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1225                 sym2 = choice;
1226
1227         dep_stack_remove();
1228
1229         return sym2;
1230 }
1231
1232 struct symbol *sym_check_deps(struct symbol *sym)
1233 {
1234         struct symbol *sym2;
1235         struct property *prop;
1236
1237         if (sym->flags & SYMBOL_CHECK) {
1238                 sym_check_print_recursive(sym);
1239                 return sym;
1240         }
1241         if (sym->flags & SYMBOL_CHECKED)
1242                 return NULL;
1243
1244         if (sym_is_choice_value(sym)) {
1245                 struct dep_stack stack;
1246
1247                 /* for choice groups start the check with main choice symbol */
1248                 dep_stack_insert(&stack, sym);
1249                 prop = sym_get_choice_prop(sym);
1250                 sym2 = sym_check_deps(prop_get_symbol(prop));
1251                 dep_stack_remove();
1252         } else if (sym_is_choice(sym)) {
1253                 sym2 = sym_check_choice_deps(sym);
1254         } else {
1255                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1256                 sym2 = sym_check_sym_deps(sym);
1257                 sym->flags &= ~SYMBOL_CHECK;
1258         }
1259
1260         if (sym2 && sym2 == sym)
1261                 sym2 = NULL;
1262
1263         return sym2;
1264 }
1265
1266 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1267 {
1268         struct property *prop;
1269         struct property **propp;
1270
1271         prop = xmalloc(sizeof(*prop));
1272         memset(prop, 0, sizeof(*prop));
1273         prop->type = type;
1274         prop->sym = sym;
1275         prop->file = current_file;
1276         prop->lineno = zconf_lineno();
1277
1278         /* append property to the prop list of symbol */
1279         if (sym) {
1280                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1281                         ;
1282                 *propp = prop;
1283         }
1284
1285         return prop;
1286 }
1287
1288 struct symbol *prop_get_symbol(struct property *prop)
1289 {
1290         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1291                            prop->expr->type == E_LIST))
1292                 return prop->expr->left.sym;
1293         return NULL;
1294 }
1295
1296 const char *prop_get_type_name(enum prop_type type)
1297 {
1298         switch (type) {
1299         case P_PROMPT:
1300                 return "prompt";
1301         case P_ENV:
1302                 return "env";
1303         case P_COMMENT:
1304                 return "comment";
1305         case P_MENU:
1306                 return "menu";
1307         case P_DEFAULT:
1308                 return "default";
1309         case P_CHOICE:
1310                 return "choice";
1311         case P_SELECT:
1312                 return "select";
1313         case P_IMPLY:
1314                 return "imply";
1315         case P_RANGE:
1316                 return "range";
1317         case P_SYMBOL:
1318                 return "symbol";
1319         case P_UNKNOWN:
1320                 break;
1321         }
1322         return "unknown";
1323 }