kconfig: fix trivial typos and update mconf documentation
[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 struct expr *sym_env_list;
37
38 static void sym_add_default(struct symbol *sym, const char *def)
39 {
40         struct property *prop = prop_alloc(P_DEFAULT, sym);
41
42         prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST));
43 }
44
45 void sym_init(void)
46 {
47         struct symbol *sym;
48         struct utsname uts;
49         static bool inited = false;
50
51         if (inited)
52                 return;
53         inited = true;
54
55         uname(&uts);
56
57         sym = sym_lookup("UNAME_RELEASE", 0);
58         sym->type = S_STRING;
59         sym->flags |= SYMBOL_AUTO;
60         sym_add_default(sym, uts.release);
61 }
62
63 enum symbol_type sym_get_type(struct symbol *sym)
64 {
65         enum symbol_type type = sym->type;
66
67         if (type == S_TRISTATE) {
68                 if (sym_is_choice_value(sym) && sym->visible == yes)
69                         type = S_BOOLEAN;
70                 else if (modules_val == no)
71                         type = S_BOOLEAN;
72         }
73         return type;
74 }
75
76 const char *sym_type_name(enum symbol_type type)
77 {
78         switch (type) {
79         case S_BOOLEAN:
80                 return "boolean";
81         case S_TRISTATE:
82                 return "tristate";
83         case S_INT:
84                 return "integer";
85         case S_HEX:
86                 return "hex";
87         case S_STRING:
88                 return "string";
89         case S_UNKNOWN:
90                 return "unknown";
91         case S_OTHER:
92                 break;
93         }
94         return "???";
95 }
96
97 struct property *sym_get_choice_prop(struct symbol *sym)
98 {
99         struct property *prop;
100
101         for_all_choices(sym, prop)
102                 return prop;
103         return NULL;
104 }
105
106 struct property *sym_get_env_prop(struct symbol *sym)
107 {
108         struct property *prop;
109
110         for_all_properties(sym, prop, P_ENV)
111                 return prop;
112         return NULL;
113 }
114
115 struct property *sym_get_default_prop(struct symbol *sym)
116 {
117         struct property *prop;
118
119         for_all_defaults(sym, prop) {
120                 prop->visible.tri = expr_calc_value(prop->visible.expr);
121                 if (prop->visible.tri != no)
122                         return prop;
123         }
124         return NULL;
125 }
126
127 static struct property *sym_get_range_prop(struct symbol *sym)
128 {
129         struct property *prop;
130
131         for_all_properties(sym, prop, P_RANGE) {
132                 prop->visible.tri = expr_calc_value(prop->visible.expr);
133                 if (prop->visible.tri != no)
134                         return prop;
135         }
136         return NULL;
137 }
138
139 static long long sym_get_range_val(struct symbol *sym, int base)
140 {
141         sym_calc_value(sym);
142         switch (sym->type) {
143         case S_INT:
144                 base = 10;
145                 break;
146         case S_HEX:
147                 base = 16;
148                 break;
149         default:
150                 break;
151         }
152         return strtoll(sym->curr.val, NULL, base);
153 }
154
155 static void sym_validate_range(struct symbol *sym)
156 {
157         struct property *prop;
158         int base;
159         long long val, val2;
160         char str[64];
161
162         switch (sym->type) {
163         case S_INT:
164                 base = 10;
165                 break;
166         case S_HEX:
167                 base = 16;
168                 break;
169         default:
170                 return;
171         }
172         prop = sym_get_range_prop(sym);
173         if (!prop)
174                 return;
175         val = strtoll(sym->curr.val, NULL, base);
176         val2 = sym_get_range_val(prop->expr->left.sym, base);
177         if (val >= val2) {
178                 val2 = sym_get_range_val(prop->expr->right.sym, base);
179                 if (val <= val2)
180                         return;
181         }
182         if (sym->type == S_INT)
183                 sprintf(str, "%lld", val2);
184         else
185                 sprintf(str, "0x%llx", val2);
186         sym->curr.val = strdup(str);
187 }
188
189 static void sym_calc_visibility(struct symbol *sym)
190 {
191         struct property *prop;
192         tristate tri;
193
194         /* any prompt visible? */
195         tri = no;
196         for_all_prompts(sym, prop) {
197                 prop->visible.tri = expr_calc_value(prop->visible.expr);
198                 tri = EXPR_OR(tri, prop->visible.tri);
199         }
200         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
201                 tri = yes;
202         if (sym->visible != tri) {
203                 sym->visible = tri;
204                 sym_set_changed(sym);
205         }
206         if (sym_is_choice_value(sym))
207                 return;
208         /* defaulting to "yes" if no explicit "depends on" are given */
209         tri = yes;
210         if (sym->dir_dep.expr)
211                 tri = expr_calc_value(sym->dir_dep.expr);
212         if (tri == mod)
213                 tri = yes;
214         if (sym->dir_dep.tri != tri) {
215                 sym->dir_dep.tri = tri;
216                 sym_set_changed(sym);
217         }
218         tri = no;
219         if (sym->rev_dep.expr)
220                 tri = expr_calc_value(sym->rev_dep.expr);
221         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
222                 tri = yes;
223         if (sym->rev_dep.tri != tri) {
224                 sym->rev_dep.tri = tri;
225                 sym_set_changed(sym);
226         }
227 }
228
229 /*
230  * Find the default symbol for a choice.
231  * First try the default values for the choice symbol
232  * Next locate the first visible choice value
233  * Return NULL if none was found
234  */
235 struct symbol *sym_choice_default(struct symbol *sym)
236 {
237         struct symbol *def_sym;
238         struct property *prop;
239         struct expr *e;
240
241         /* any of the defaults visible? */
242         for_all_defaults(sym, prop) {
243                 prop->visible.tri = expr_calc_value(prop->visible.expr);
244                 if (prop->visible.tri == no)
245                         continue;
246                 def_sym = prop_get_symbol(prop);
247                 if (def_sym->visible != no)
248                         return def_sym;
249         }
250
251         /* just get the first visible value */
252         prop = sym_get_choice_prop(sym);
253         expr_list_for_each_sym(prop->expr, e, def_sym)
254                 if (def_sym->visible != no)
255                         return def_sym;
256
257         /* failed to locate any defaults */
258         return NULL;
259 }
260
261 static struct symbol *sym_calc_choice(struct symbol *sym)
262 {
263         struct symbol *def_sym;
264         struct property *prop;
265         struct expr *e;
266         int flags;
267
268         /* first calculate all choice values' visibilities */
269         flags = sym->flags;
270         prop = sym_get_choice_prop(sym);
271         expr_list_for_each_sym(prop->expr, e, def_sym) {
272                 sym_calc_visibility(def_sym);
273                 if (def_sym->visible != no)
274                         flags &= def_sym->flags;
275         }
276
277         sym->flags &= flags | ~SYMBOL_DEF_USER;
278
279         /* is the user choice visible? */
280         def_sym = sym->def[S_DEF_USER].val;
281         if (def_sym && def_sym->visible != no)
282                 return def_sym;
283
284         def_sym = sym_choice_default(sym);
285
286         if (def_sym == NULL)
287                 /* no choice? reset tristate value */
288                 sym->curr.tri = no;
289
290         return def_sym;
291 }
292
293 void sym_calc_value(struct symbol *sym)
294 {
295         struct symbol_value newval, oldval;
296         struct property *prop;
297         struct expr *e;
298
299         if (!sym)
300                 return;
301
302         if (sym->flags & SYMBOL_VALID)
303                 return;
304
305         if (sym_is_choice_value(sym) &&
306             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
307                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
308                 prop = sym_get_choice_prop(sym);
309                 sym_calc_value(prop_get_symbol(prop));
310         }
311
312         sym->flags |= SYMBOL_VALID;
313
314         oldval = sym->curr;
315
316         switch (sym->type) {
317         case S_INT:
318         case S_HEX:
319         case S_STRING:
320                 newval = symbol_empty.curr;
321                 break;
322         case S_BOOLEAN:
323         case S_TRISTATE:
324                 newval = symbol_no.curr;
325                 break;
326         default:
327                 sym->curr.val = sym->name;
328                 sym->curr.tri = no;
329                 return;
330         }
331         if (!sym_is_choice_value(sym))
332                 sym->flags &= ~SYMBOL_WRITE;
333
334         sym_calc_visibility(sym);
335
336         /* set default if recursively called */
337         sym->curr = newval;
338
339         switch (sym_get_type(sym)) {
340         case S_BOOLEAN:
341         case S_TRISTATE:
342                 if (sym_is_choice_value(sym) && sym->visible == yes) {
343                         prop = sym_get_choice_prop(sym);
344                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
345                 } else {
346                         if (sym->visible != no) {
347                                 /* if the symbol is visible use the user value
348                                  * if available, otherwise try the default value
349                                  */
350                                 sym->flags |= SYMBOL_WRITE;
351                                 if (sym_has_value(sym)) {
352                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
353                                                               sym->visible);
354                                         goto calc_newval;
355                                 }
356                         }
357                         if (sym->rev_dep.tri != no)
358                                 sym->flags |= SYMBOL_WRITE;
359                         if (!sym_is_choice(sym)) {
360                                 prop = sym_get_default_prop(sym);
361                                 if (prop) {
362                                         sym->flags |= SYMBOL_WRITE;
363                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
364                                                               prop->visible.tri);
365                                 }
366                         }
367                 calc_newval:
368                         if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
369                                 struct expr *e;
370                                 e = expr_simplify_unmet_dep(sym->rev_dep.expr,
371                                     sym->dir_dep.expr);
372                                 fprintf(stderr, "warning: (");
373                                 expr_fprint(e, stderr);
374                                 fprintf(stderr, ") selects %s which has unmet direct dependencies (",
375                                         sym->name);
376                                 expr_fprint(sym->dir_dep.expr, stderr);
377                                 fprintf(stderr, ")\n");
378                                 expr_free(e);
379                         }
380                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
381                 }
382                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
383                         newval.tri = yes;
384                 break;
385         case S_STRING:
386         case S_HEX:
387         case S_INT:
388                 if (sym->visible != no) {
389                         sym->flags |= SYMBOL_WRITE;
390                         if (sym_has_value(sym)) {
391                                 newval.val = sym->def[S_DEF_USER].val;
392                                 break;
393                         }
394                 }
395                 prop = sym_get_default_prop(sym);
396                 if (prop) {
397                         struct symbol *ds = prop_get_symbol(prop);
398                         if (ds) {
399                                 sym->flags |= SYMBOL_WRITE;
400                                 sym_calc_value(ds);
401                                 newval.val = ds->curr.val;
402                         }
403                 }
404                 break;
405         default:
406                 ;
407         }
408
409         sym->curr = newval;
410         if (sym_is_choice(sym) && newval.tri == yes)
411                 sym->curr.val = sym_calc_choice(sym);
412         sym_validate_range(sym);
413
414         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
415                 sym_set_changed(sym);
416                 if (modules_sym == sym) {
417                         sym_set_all_changed();
418                         modules_val = modules_sym->curr.tri;
419                 }
420         }
421
422         if (sym_is_choice(sym)) {
423                 struct symbol *choice_sym;
424
425                 prop = sym_get_choice_prop(sym);
426                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
427                         if ((sym->flags & SYMBOL_WRITE) &&
428                             choice_sym->visible != no)
429                                 choice_sym->flags |= SYMBOL_WRITE;
430                         if (sym->flags & SYMBOL_CHANGED)
431                                 sym_set_changed(choice_sym);
432                 }
433         }
434
435         if (sym->flags & SYMBOL_AUTO)
436                 sym->flags &= ~SYMBOL_WRITE;
437
438         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
439                 set_all_choice_values(sym);
440 }
441
442 void sym_clear_all_valid(void)
443 {
444         struct symbol *sym;
445         int i;
446
447         for_all_symbols(i, sym)
448                 sym->flags &= ~SYMBOL_VALID;
449         sym_add_change_count(1);
450         if (modules_sym)
451                 sym_calc_value(modules_sym);
452 }
453
454 void sym_set_changed(struct symbol *sym)
455 {
456         struct property *prop;
457
458         sym->flags |= SYMBOL_CHANGED;
459         for (prop = sym->prop; prop; prop = prop->next) {
460                 if (prop->menu)
461                         prop->menu->flags |= MENU_CHANGED;
462         }
463 }
464
465 void sym_set_all_changed(void)
466 {
467         struct symbol *sym;
468         int i;
469
470         for_all_symbols(i, sym)
471                 sym_set_changed(sym);
472 }
473
474 bool sym_tristate_within_range(struct symbol *sym, tristate val)
475 {
476         int type = sym_get_type(sym);
477
478         if (sym->visible == no)
479                 return false;
480
481         if (type != S_BOOLEAN && type != S_TRISTATE)
482                 return false;
483
484         if (type == S_BOOLEAN && val == mod)
485                 return false;
486         if (sym->visible <= sym->rev_dep.tri)
487                 return false;
488         if (sym_is_choice_value(sym) && sym->visible == yes)
489                 return val == yes;
490         return val >= sym->rev_dep.tri && val <= sym->visible;
491 }
492
493 bool sym_set_tristate_value(struct symbol *sym, tristate val)
494 {
495         tristate oldval = sym_get_tristate_value(sym);
496
497         if (oldval != val && !sym_tristate_within_range(sym, val))
498                 return false;
499
500         if (!(sym->flags & SYMBOL_DEF_USER)) {
501                 sym->flags |= SYMBOL_DEF_USER;
502                 sym_set_changed(sym);
503         }
504         /*
505          * setting a choice value also resets the new flag of the choice
506          * symbol and all other choice values.
507          */
508         if (sym_is_choice_value(sym) && val == yes) {
509                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
510                 struct property *prop;
511                 struct expr *e;
512
513                 cs->def[S_DEF_USER].val = sym;
514                 cs->flags |= SYMBOL_DEF_USER;
515                 prop = sym_get_choice_prop(cs);
516                 for (e = prop->expr; e; e = e->left.expr) {
517                         if (e->right.sym->visible != no)
518                                 e->right.sym->flags |= SYMBOL_DEF_USER;
519                 }
520         }
521
522         sym->def[S_DEF_USER].tri = val;
523         if (oldval != val)
524                 sym_clear_all_valid();
525
526         return true;
527 }
528
529 tristate sym_toggle_tristate_value(struct symbol *sym)
530 {
531         tristate oldval, newval;
532
533         oldval = newval = sym_get_tristate_value(sym);
534         do {
535                 switch (newval) {
536                 case no:
537                         newval = mod;
538                         break;
539                 case mod:
540                         newval = yes;
541                         break;
542                 case yes:
543                         newval = no;
544                         break;
545                 }
546                 if (sym_set_tristate_value(sym, newval))
547                         break;
548         } while (oldval != newval);
549         return newval;
550 }
551
552 bool sym_string_valid(struct symbol *sym, const char *str)
553 {
554         signed char ch;
555
556         switch (sym->type) {
557         case S_STRING:
558                 return true;
559         case S_INT:
560                 ch = *str++;
561                 if (ch == '-')
562                         ch = *str++;
563                 if (!isdigit(ch))
564                         return false;
565                 if (ch == '0' && *str != 0)
566                         return false;
567                 while ((ch = *str++)) {
568                         if (!isdigit(ch))
569                                 return false;
570                 }
571                 return true;
572         case S_HEX:
573                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
574                         str += 2;
575                 ch = *str++;
576                 do {
577                         if (!isxdigit(ch))
578                                 return false;
579                 } while ((ch = *str++));
580                 return true;
581         case S_BOOLEAN:
582         case S_TRISTATE:
583                 switch (str[0]) {
584                 case 'y': case 'Y':
585                 case 'm': case 'M':
586                 case 'n': case 'N':
587                         return true;
588                 }
589                 return false;
590         default:
591                 return false;
592         }
593 }
594
595 bool sym_string_within_range(struct symbol *sym, const char *str)
596 {
597         struct property *prop;
598         long long val;
599
600         switch (sym->type) {
601         case S_STRING:
602                 return sym_string_valid(sym, str);
603         case S_INT:
604                 if (!sym_string_valid(sym, str))
605                         return false;
606                 prop = sym_get_range_prop(sym);
607                 if (!prop)
608                         return true;
609                 val = strtoll(str, NULL, 10);
610                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
611                        val <= sym_get_range_val(prop->expr->right.sym, 10);
612         case S_HEX:
613                 if (!sym_string_valid(sym, str))
614                         return false;
615                 prop = sym_get_range_prop(sym);
616                 if (!prop)
617                         return true;
618                 val = strtoll(str, NULL, 16);
619                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
620                        val <= sym_get_range_val(prop->expr->right.sym, 16);
621         case S_BOOLEAN:
622         case S_TRISTATE:
623                 switch (str[0]) {
624                 case 'y': case 'Y':
625                         return sym_tristate_within_range(sym, yes);
626                 case 'm': case 'M':
627                         return sym_tristate_within_range(sym, mod);
628                 case 'n': case 'N':
629                         return sym_tristate_within_range(sym, no);
630                 }
631                 return false;
632         default:
633                 return false;
634         }
635 }
636
637 bool sym_set_string_value(struct symbol *sym, const char *newval)
638 {
639         const char *oldval;
640         char *val;
641         int size;
642
643         switch (sym->type) {
644         case S_BOOLEAN:
645         case S_TRISTATE:
646                 switch (newval[0]) {
647                 case 'y': case 'Y':
648                         return sym_set_tristate_value(sym, yes);
649                 case 'm': case 'M':
650                         return sym_set_tristate_value(sym, mod);
651                 case 'n': case 'N':
652                         return sym_set_tristate_value(sym, no);
653                 }
654                 return false;
655         default:
656                 ;
657         }
658
659         if (!sym_string_within_range(sym, newval))
660                 return false;
661
662         if (!(sym->flags & SYMBOL_DEF_USER)) {
663                 sym->flags |= SYMBOL_DEF_USER;
664                 sym_set_changed(sym);
665         }
666
667         oldval = sym->def[S_DEF_USER].val;
668         size = strlen(newval) + 1;
669         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
670                 size += 2;
671                 sym->def[S_DEF_USER].val = val = xmalloc(size);
672                 *val++ = '0';
673                 *val++ = 'x';
674         } else if (!oldval || strcmp(oldval, newval))
675                 sym->def[S_DEF_USER].val = val = xmalloc(size);
676         else
677                 return true;
678
679         strcpy(val, newval);
680         free((void *)oldval);
681         sym_clear_all_valid();
682
683         return true;
684 }
685
686 /*
687  * Find the default value associated to a symbol.
688  * For tristate symbol handle the modules=n case
689  * in which case "m" becomes "y".
690  * If the symbol does not have any default then fallback
691  * to the fixed default values.
692  */
693 const char *sym_get_string_default(struct symbol *sym)
694 {
695         struct property *prop;
696         struct symbol *ds;
697         const char *str;
698         tristate val;
699
700         sym_calc_visibility(sym);
701         sym_calc_value(modules_sym);
702         val = symbol_no.curr.tri;
703         str = symbol_empty.curr.val;
704
705         /* If symbol has a default value look it up */
706         prop = sym_get_default_prop(sym);
707         if (prop != NULL) {
708                 switch (sym->type) {
709                 case S_BOOLEAN:
710                 case S_TRISTATE:
711                         /* The visibility may limit the value from yes => mod */
712                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
713                         break;
714                 default:
715                         /*
716                          * The following fails to handle the situation
717                          * where a default value is further limited by
718                          * the valid range.
719                          */
720                         ds = prop_get_symbol(prop);
721                         if (ds != NULL) {
722                                 sym_calc_value(ds);
723                                 str = (const char *)ds->curr.val;
724                         }
725                 }
726         }
727
728         /* Handle select statements */
729         val = EXPR_OR(val, sym->rev_dep.tri);
730
731         /* transpose mod to yes if modules are not enabled */
732         if (val == mod)
733                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
734                         val = yes;
735
736         /* transpose mod to yes if type is bool */
737         if (sym->type == S_BOOLEAN && val == mod)
738                 val = yes;
739
740         switch (sym->type) {
741         case S_BOOLEAN:
742         case S_TRISTATE:
743                 switch (val) {
744                 case no: return "n";
745                 case mod: return "m";
746                 case yes: return "y";
747                 }
748         case S_INT:
749         case S_HEX:
750                 return str;
751         case S_STRING:
752                 return str;
753         case S_OTHER:
754         case S_UNKNOWN:
755                 break;
756         }
757         return "";
758 }
759
760 const char *sym_get_string_value(struct symbol *sym)
761 {
762         tristate val;
763
764         switch (sym->type) {
765         case S_BOOLEAN:
766         case S_TRISTATE:
767                 val = sym_get_tristate_value(sym);
768                 switch (val) {
769                 case no:
770                         return "n";
771                 case mod:
772                         sym_calc_value(modules_sym);
773                         return (modules_sym->curr.tri == no) ? "n" : "m";
774                 case yes:
775                         return "y";
776                 }
777                 break;
778         default:
779                 ;
780         }
781         return (const char *)sym->curr.val;
782 }
783
784 bool sym_is_changable(struct symbol *sym)
785 {
786         return sym->visible > sym->rev_dep.tri;
787 }
788
789 static unsigned strhash(const char *s)
790 {
791         /* fnv32 hash */
792         unsigned hash = 2166136261U;
793         for (; *s; s++)
794                 hash = (hash ^ *s) * 0x01000193;
795         return hash;
796 }
797
798 struct symbol *sym_lookup(const char *name, int flags)
799 {
800         struct symbol *symbol;
801         char *new_name;
802         int hash;
803
804         if (name) {
805                 if (name[0] && !name[1]) {
806                         switch (name[0]) {
807                         case 'y': return &symbol_yes;
808                         case 'm': return &symbol_mod;
809                         case 'n': return &symbol_no;
810                         }
811                 }
812                 hash = strhash(name) % SYMBOL_HASHSIZE;
813
814                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
815                         if (symbol->name &&
816                             !strcmp(symbol->name, name) &&
817                             (flags ? symbol->flags & flags
818                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
819                                 return symbol;
820                 }
821                 new_name = strdup(name);
822         } else {
823                 new_name = NULL;
824                 hash = 0;
825         }
826
827         symbol = xmalloc(sizeof(*symbol));
828         memset(symbol, 0, sizeof(*symbol));
829         symbol->name = new_name;
830         symbol->type = S_UNKNOWN;
831         symbol->flags |= flags;
832
833         symbol->next = symbol_hash[hash];
834         symbol_hash[hash] = symbol;
835
836         return symbol;
837 }
838
839 struct symbol *sym_find(const char *name)
840 {
841         struct symbol *symbol = NULL;
842         int hash = 0;
843
844         if (!name)
845                 return NULL;
846
847         if (name[0] && !name[1]) {
848                 switch (name[0]) {
849                 case 'y': return &symbol_yes;
850                 case 'm': return &symbol_mod;
851                 case 'n': return &symbol_no;
852                 }
853         }
854         hash = strhash(name) % SYMBOL_HASHSIZE;
855
856         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
857                 if (symbol->name &&
858                     !strcmp(symbol->name, name) &&
859                     !(symbol->flags & SYMBOL_CONST))
860                                 break;
861         }
862
863         return symbol;
864 }
865
866 /*
867  * Expand symbol's names embedded in the string given in argument. Symbols'
868  * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
869  * the empty string.
870  */
871 const char *sym_expand_string_value(const char *in)
872 {
873         const char *src;
874         char *res;
875         size_t reslen;
876
877         reslen = strlen(in) + 1;
878         res = xmalloc(reslen);
879         res[0] = '\0';
880
881         while ((src = strchr(in, '$'))) {
882                 char *p, name[SYMBOL_MAXLENGTH];
883                 const char *symval = "";
884                 struct symbol *sym;
885                 size_t newlen;
886
887                 strncat(res, in, src - in);
888                 src++;
889
890                 p = name;
891                 while (isalnum(*src) || *src == '_')
892                         *p++ = *src++;
893                 *p = '\0';
894
895                 sym = sym_find(name);
896                 if (sym != NULL) {
897                         sym_calc_value(sym);
898                         symval = sym_get_string_value(sym);
899                 }
900
901                 newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
902                 if (newlen > reslen) {
903                         reslen = newlen;
904                         res = realloc(res, reslen);
905                 }
906
907                 strcat(res, symval);
908                 in = src;
909         }
910         strcat(res, in);
911
912         return res;
913 }
914
915 const char *sym_escape_string_value(const char *in)
916 {
917         const char *p;
918         size_t reslen;
919         char *res;
920         size_t l;
921
922         reslen = strlen(in) + strlen("\"\"") + 1;
923
924         p = in;
925         for (;;) {
926                 l = strcspn(p, "\"\\");
927                 p += l;
928
929                 if (p[0] == '\0')
930                         break;
931
932                 reslen++;
933                 p++;
934         }
935
936         res = xmalloc(reslen);
937         res[0] = '\0';
938
939         strcat(res, "\"");
940
941         p = in;
942         for (;;) {
943                 l = strcspn(p, "\"\\");
944                 strncat(res, p, l);
945                 p += l;
946
947                 if (p[0] == '\0')
948                         break;
949
950                 strcat(res, "\\");
951                 strncat(res, p++, 1);
952         }
953
954         strcat(res, "\"");
955         return res;
956 }
957
958 struct sym_match {
959         struct symbol   *sym;
960         off_t           so, eo;
961 };
962
963 /* Compare matched symbols as thus:
964  * - first, symbols that match exactly
965  * - then, alphabetical sort
966  */
967 static int sym_rel_comp(const void *sym1, const void *sym2)
968 {
969         const struct sym_match *s1 = sym1;
970         const struct sym_match *s2 = sym2;
971         int exact1, exact2;
972
973         /* Exact match:
974          * - if matched length on symbol s1 is the length of that symbol,
975          *   then this symbol should come first;
976          * - if matched length on symbol s2 is the length of that symbol,
977          *   then this symbol should come first.
978          * Note: since the search can be a regexp, both symbols may match
979          * exactly; if this is the case, we can't decide which comes first,
980          * and we fallback to sorting alphabetically.
981          */
982         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
983         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
984         if (exact1 && !exact2)
985                 return -1;
986         if (!exact1 && exact2)
987                 return 1;
988
989         /* As a fallback, sort symbols alphabetically */
990         return strcmp(s1->sym->name, s2->sym->name);
991 }
992
993 struct symbol **sym_re_search(const char *pattern)
994 {
995         struct symbol *sym, **sym_arr = NULL;
996         struct sym_match *sym_match_arr = NULL;
997         int i, cnt, size;
998         regex_t re;
999         regmatch_t match[1];
1000
1001         cnt = size = 0;
1002         /* Skip if empty */
1003         if (strlen(pattern) == 0)
1004                 return NULL;
1005         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
1006                 return NULL;
1007
1008         for_all_symbols(i, sym) {
1009                 if (sym->flags & SYMBOL_CONST || !sym->name)
1010                         continue;
1011                 if (regexec(&re, sym->name, 1, match, 0))
1012                         continue;
1013                 if (cnt >= size) {
1014                         void *tmp;
1015                         size += 16;
1016                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
1017                         if (!tmp)
1018                                 goto sym_re_search_free;
1019                         sym_match_arr = tmp;
1020                 }
1021                 sym_calc_value(sym);
1022                 /* As regexec returned 0, we know we have a match, so
1023                  * we can use match[0].rm_[se]o without further checks
1024                  */
1025                 sym_match_arr[cnt].so = match[0].rm_so;
1026                 sym_match_arr[cnt].eo = match[0].rm_eo;
1027                 sym_match_arr[cnt++].sym = sym;
1028         }
1029         if (sym_match_arr) {
1030                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
1031                 sym_arr = malloc((cnt+1) * sizeof(struct symbol));
1032                 if (!sym_arr)
1033                         goto sym_re_search_free;
1034                 for (i = 0; i < cnt; i++)
1035                         sym_arr[i] = sym_match_arr[i].sym;
1036                 sym_arr[cnt] = NULL;
1037         }
1038 sym_re_search_free:
1039         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1040         free(sym_match_arr);
1041         regfree(&re);
1042
1043         return sym_arr;
1044 }
1045
1046 /*
1047  * When we check for recursive dependencies we use a stack to save
1048  * current state so we can print out relevant info to user.
1049  * The entries are located on the call stack so no need to free memory.
1050  * Note insert() remove() must always match to properly clear the stack.
1051  */
1052 static struct dep_stack {
1053         struct dep_stack *prev, *next;
1054         struct symbol *sym;
1055         struct property *prop;
1056         struct expr *expr;
1057 } *check_top;
1058
1059 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1060 {
1061         memset(stack, 0, sizeof(*stack));
1062         if (check_top)
1063                 check_top->next = stack;
1064         stack->prev = check_top;
1065         stack->sym = sym;
1066         check_top = stack;
1067 }
1068
1069 static void dep_stack_remove(void)
1070 {
1071         check_top = check_top->prev;
1072         if (check_top)
1073                 check_top->next = NULL;
1074 }
1075
1076 /*
1077  * Called when we have detected a recursive dependency.
1078  * check_top point to the top of the stact so we use
1079  * the ->prev pointer to locate the bottom of the stack.
1080  */
1081 static void sym_check_print_recursive(struct symbol *last_sym)
1082 {
1083         struct dep_stack *stack;
1084         struct symbol *sym, *next_sym;
1085         struct menu *menu = NULL;
1086         struct property *prop;
1087         struct dep_stack cv_stack;
1088
1089         if (sym_is_choice_value(last_sym)) {
1090                 dep_stack_insert(&cv_stack, last_sym);
1091                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1092         }
1093
1094         for (stack = check_top; stack != NULL; stack = stack->prev)
1095                 if (stack->sym == last_sym)
1096                         break;
1097         if (!stack) {
1098                 fprintf(stderr, "unexpected recursive dependency error\n");
1099                 return;
1100         }
1101
1102         for (; stack; stack = stack->next) {
1103                 sym = stack->sym;
1104                 next_sym = stack->next ? stack->next->sym : last_sym;
1105                 prop = stack->prop;
1106                 if (prop == NULL)
1107                         prop = stack->sym->prop;
1108
1109                 /* for choice values find the menu entry (used below) */
1110                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1111                         for (prop = sym->prop; prop; prop = prop->next) {
1112                                 menu = prop->menu;
1113                                 if (prop->menu)
1114                                         break;
1115                         }
1116                 }
1117                 if (stack->sym == last_sym)
1118                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1119                                 prop->file->name, prop->lineno);
1120                 if (stack->expr) {
1121                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1122                                 prop->file->name, prop->lineno,
1123                                 sym->name ? sym->name : "<choice>",
1124                                 prop_get_type_name(prop->type),
1125                                 next_sym->name ? next_sym->name : "<choice>");
1126                 } else if (stack->prop) {
1127                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1128                                 prop->file->name, prop->lineno,
1129                                 sym->name ? sym->name : "<choice>",
1130                                 next_sym->name ? next_sym->name : "<choice>");
1131                 } else if (sym_is_choice(sym)) {
1132                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1133                                 menu->file->name, menu->lineno,
1134                                 sym->name ? sym->name : "<choice>",
1135                                 next_sym->name ? next_sym->name : "<choice>");
1136                 } else if (sym_is_choice_value(sym)) {
1137                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1138                                 menu->file->name, menu->lineno,
1139                                 sym->name ? sym->name : "<choice>",
1140                                 next_sym->name ? next_sym->name : "<choice>");
1141                 } else {
1142                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1143                                 prop->file->name, prop->lineno,
1144                                 sym->name ? sym->name : "<choice>",
1145                                 next_sym->name ? next_sym->name : "<choice>");
1146                 }
1147         }
1148
1149         if (check_top == &cv_stack)
1150                 dep_stack_remove();
1151 }
1152
1153 static struct symbol *sym_check_expr_deps(struct expr *e)
1154 {
1155         struct symbol *sym;
1156
1157         if (!e)
1158                 return NULL;
1159         switch (e->type) {
1160         case E_OR:
1161         case E_AND:
1162                 sym = sym_check_expr_deps(e->left.expr);
1163                 if (sym)
1164                         return sym;
1165                 return sym_check_expr_deps(e->right.expr);
1166         case E_NOT:
1167                 return sym_check_expr_deps(e->left.expr);
1168         case E_EQUAL:
1169         case E_UNEQUAL:
1170                 sym = sym_check_deps(e->left.sym);
1171                 if (sym)
1172                         return sym;
1173                 return sym_check_deps(e->right.sym);
1174         case E_SYMBOL:
1175                 return sym_check_deps(e->left.sym);
1176         default:
1177                 break;
1178         }
1179         printf("Oops! How to check %d?\n", e->type);
1180         return NULL;
1181 }
1182
1183 /* return NULL when dependencies are OK */
1184 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1185 {
1186         struct symbol *sym2;
1187         struct property *prop;
1188         struct dep_stack stack;
1189
1190         dep_stack_insert(&stack, sym);
1191
1192         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1193         if (sym2)
1194                 goto out;
1195
1196         for (prop = sym->prop; prop; prop = prop->next) {
1197                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1198                         continue;
1199                 stack.prop = prop;
1200                 sym2 = sym_check_expr_deps(prop->visible.expr);
1201                 if (sym2)
1202                         break;
1203                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1204                         continue;
1205                 stack.expr = prop->expr;
1206                 sym2 = sym_check_expr_deps(prop->expr);
1207                 if (sym2)
1208                         break;
1209                 stack.expr = NULL;
1210         }
1211
1212 out:
1213         dep_stack_remove();
1214
1215         return sym2;
1216 }
1217
1218 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1219 {
1220         struct symbol *sym, *sym2;
1221         struct property *prop;
1222         struct expr *e;
1223         struct dep_stack stack;
1224
1225         dep_stack_insert(&stack, choice);
1226
1227         prop = sym_get_choice_prop(choice);
1228         expr_list_for_each_sym(prop->expr, e, sym)
1229                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1230
1231         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1232         sym2 = sym_check_sym_deps(choice);
1233         choice->flags &= ~SYMBOL_CHECK;
1234         if (sym2)
1235                 goto out;
1236
1237         expr_list_for_each_sym(prop->expr, e, sym) {
1238                 sym2 = sym_check_sym_deps(sym);
1239                 if (sym2)
1240                         break;
1241         }
1242 out:
1243         expr_list_for_each_sym(prop->expr, e, sym)
1244                 sym->flags &= ~SYMBOL_CHECK;
1245
1246         if (sym2 && sym_is_choice_value(sym2) &&
1247             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1248                 sym2 = choice;
1249
1250         dep_stack_remove();
1251
1252         return sym2;
1253 }
1254
1255 struct symbol *sym_check_deps(struct symbol *sym)
1256 {
1257         struct symbol *sym2;
1258         struct property *prop;
1259
1260         if (sym->flags & SYMBOL_CHECK) {
1261                 sym_check_print_recursive(sym);
1262                 return sym;
1263         }
1264         if (sym->flags & SYMBOL_CHECKED)
1265                 return NULL;
1266
1267         if (sym_is_choice_value(sym)) {
1268                 struct dep_stack stack;
1269
1270                 /* for choice groups start the check with main choice symbol */
1271                 dep_stack_insert(&stack, sym);
1272                 prop = sym_get_choice_prop(sym);
1273                 sym2 = sym_check_deps(prop_get_symbol(prop));
1274                 dep_stack_remove();
1275         } else if (sym_is_choice(sym)) {
1276                 sym2 = sym_check_choice_deps(sym);
1277         } else {
1278                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1279                 sym2 = sym_check_sym_deps(sym);
1280                 sym->flags &= ~SYMBOL_CHECK;
1281         }
1282
1283         if (sym2 && sym2 == sym)
1284                 sym2 = NULL;
1285
1286         return sym2;
1287 }
1288
1289 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1290 {
1291         struct property *prop;
1292         struct property **propp;
1293
1294         prop = xmalloc(sizeof(*prop));
1295         memset(prop, 0, sizeof(*prop));
1296         prop->type = type;
1297         prop->sym = sym;
1298         prop->file = current_file;
1299         prop->lineno = zconf_lineno();
1300
1301         /* append property to the prop list of symbol */
1302         if (sym) {
1303                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1304                         ;
1305                 *propp = prop;
1306         }
1307
1308         return prop;
1309 }
1310
1311 struct symbol *prop_get_symbol(struct property *prop)
1312 {
1313         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1314                            prop->expr->type == E_LIST))
1315                 return prop->expr->left.sym;
1316         return NULL;
1317 }
1318
1319 const char *prop_get_type_name(enum prop_type type)
1320 {
1321         switch (type) {
1322         case P_PROMPT:
1323                 return "prompt";
1324         case P_ENV:
1325                 return "env";
1326         case P_COMMENT:
1327                 return "comment";
1328         case P_MENU:
1329                 return "menu";
1330         case P_DEFAULT:
1331                 return "default";
1332         case P_CHOICE:
1333                 return "choice";
1334         case P_SELECT:
1335                 return "select";
1336         case P_RANGE:
1337                 return "range";
1338         case P_SYMBOL:
1339                 return "symbol";
1340         case P_UNKNOWN:
1341                 break;
1342         }
1343         return "unknown";
1344 }
1345
1346 static void prop_add_env(const char *env)
1347 {
1348         struct symbol *sym, *sym2;
1349         struct property *prop;
1350         char *p;
1351
1352         sym = current_entry->sym;
1353         sym->flags |= SYMBOL_AUTO;
1354         for_all_properties(sym, prop, P_ENV) {
1355                 sym2 = prop_get_symbol(prop);
1356                 if (strcmp(sym2->name, env))
1357                         menu_warn(current_entry, "redefining environment symbol from %s",
1358                                   sym2->name);
1359                 return;
1360         }
1361
1362         prop = prop_alloc(P_ENV, sym);
1363         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1364
1365         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1366         sym_env_list->right.sym = sym;
1367
1368         p = getenv(env);
1369         if (p)
1370                 sym_add_default(sym, p);
1371         else
1372                 menu_warn(current_entry, "environment variable %s undefined", env);
1373 }