cf8edf4fc429a70eb8e3d9e876a2e3d0b98b7f86
[pandora-kernel.git] / scripts / kconfig / 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 int 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 strtol(sym->curr.val, NULL, base);
153 }
154
155 static void sym_validate_range(struct symbol *sym)
156 {
157         struct property *prop;
158         int base, val, val2;
159         char str[64];
160
161         switch (sym->type) {
162         case S_INT:
163                 base = 10;
164                 break;
165         case S_HEX:
166                 base = 16;
167                 break;
168         default:
169                 return;
170         }
171         prop = sym_get_range_prop(sym);
172         if (!prop)
173                 return;
174         val = strtol(sym->curr.val, NULL, base);
175         val2 = sym_get_range_val(prop->expr->left.sym, base);
176         if (val >= val2) {
177                 val2 = sym_get_range_val(prop->expr->right.sym, base);
178                 if (val <= val2)
179                         return;
180         }
181         if (sym->type == S_INT)
182                 sprintf(str, "%d", val2);
183         else
184                 sprintf(str, "0x%x", val2);
185         sym->curr.val = strdup(str);
186 }
187
188 static void sym_calc_visibility(struct symbol *sym)
189 {
190         struct property *prop;
191         tristate tri;
192
193         /* any prompt visible? */
194         tri = no;
195         for_all_prompts(sym, prop) {
196                 prop->visible.tri = expr_calc_value(prop->visible.expr);
197                 tri = EXPR_OR(tri, prop->visible.tri);
198         }
199         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
200                 tri = yes;
201         if (sym->visible != tri) {
202                 sym->visible = tri;
203                 sym_set_changed(sym);
204         }
205         if (sym_is_choice_value(sym))
206                 return;
207         /* defaulting to "yes" if no explicit "depends on" are given */
208         tri = yes;
209         if (sym->dir_dep.expr)
210                 tri = expr_calc_value(sym->dir_dep.expr);
211         if (tri == mod)
212                 tri = yes;
213         if (sym->dir_dep.tri != tri) {
214                 sym->dir_dep.tri = tri;
215                 sym_set_changed(sym);
216         }
217         tri = no;
218         if (sym->rev_dep.expr)
219                 tri = expr_calc_value(sym->rev_dep.expr);
220         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
221                 tri = yes;
222         if (sym->rev_dep.tri != tri) {
223                 sym->rev_dep.tri = tri;
224                 sym_set_changed(sym);
225         }
226 }
227
228 /*
229  * Find the default symbol for a choice.
230  * First try the default values for the choice symbol
231  * Next locate the first visible choice value
232  * Return NULL if none was found
233  */
234 struct symbol *sym_choice_default(struct symbol *sym)
235 {
236         struct symbol *def_sym;
237         struct property *prop;
238         struct expr *e;
239
240         /* any of the defaults visible? */
241         for_all_defaults(sym, prop) {
242                 prop->visible.tri = expr_calc_value(prop->visible.expr);
243                 if (prop->visible.tri == no)
244                         continue;
245                 def_sym = prop_get_symbol(prop);
246                 if (def_sym->visible != no)
247                         return def_sym;
248         }
249
250         /* just get the first visible value */
251         prop = sym_get_choice_prop(sym);
252         expr_list_for_each_sym(prop->expr, e, def_sym)
253                 if (def_sym->visible != no)
254                         return def_sym;
255
256         /* failed to locate any defaults */
257         return NULL;
258 }
259
260 static struct symbol *sym_calc_choice(struct symbol *sym)
261 {
262         struct symbol *def_sym;
263         struct property *prop;
264         struct expr *e;
265
266         /* first calculate all choice values' visibilities */
267         prop = sym_get_choice_prop(sym);
268         expr_list_for_each_sym(prop->expr, e, def_sym)
269                 sym_calc_visibility(def_sym);
270
271         /* is the user choice visible? */
272         def_sym = sym->def[S_DEF_USER].val;
273         if (def_sym && def_sym->visible != no)
274                 return def_sym;
275
276         def_sym = sym_choice_default(sym);
277
278         if (def_sym == NULL)
279                 /* no choice? reset tristate value */
280                 sym->curr.tri = no;
281
282         return def_sym;
283 }
284
285 void sym_calc_value(struct symbol *sym)
286 {
287         struct symbol_value newval, oldval;
288         struct property *prop;
289         struct expr *e;
290
291         if (!sym)
292                 return;
293
294         if (sym->flags & SYMBOL_VALID)
295                 return;
296         sym->flags |= SYMBOL_VALID;
297
298         oldval = sym->curr;
299
300         switch (sym->type) {
301         case S_INT:
302         case S_HEX:
303         case S_STRING:
304                 newval = symbol_empty.curr;
305                 break;
306         case S_BOOLEAN:
307         case S_TRISTATE:
308                 newval = symbol_no.curr;
309                 break;
310         default:
311                 sym->curr.val = sym->name;
312                 sym->curr.tri = no;
313                 return;
314         }
315         if (!sym_is_choice_value(sym))
316                 sym->flags &= ~SYMBOL_WRITE;
317
318         sym_calc_visibility(sym);
319
320         /* set default if recursively called */
321         sym->curr = newval;
322
323         switch (sym_get_type(sym)) {
324         case S_BOOLEAN:
325         case S_TRISTATE:
326                 if (sym_is_choice_value(sym) && sym->visible == yes) {
327                         prop = sym_get_choice_prop(sym);
328                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
329                 } else {
330                         if (sym->visible != no) {
331                                 /* if the symbol is visible use the user value
332                                  * if available, otherwise try the default value
333                                  */
334                                 sym->flags |= SYMBOL_WRITE;
335                                 if (sym_has_value(sym)) {
336                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
337                                                               sym->visible);
338                                         goto calc_newval;
339                                 }
340                         }
341                         if (sym->rev_dep.tri != no)
342                                 sym->flags |= SYMBOL_WRITE;
343                         if (!sym_is_choice(sym)) {
344                                 prop = sym_get_default_prop(sym);
345                                 if (prop) {
346                                         sym->flags |= SYMBOL_WRITE;
347                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
348                                                               prop->visible.tri);
349                                 }
350                         }
351                 calc_newval:
352                         if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
353                                 struct expr *e;
354                                 e = expr_simplify_unmet_dep(sym->rev_dep.expr,
355                                     sym->dir_dep.expr);
356                                 fprintf(stderr, "warning: (");
357                                 expr_fprint(e, stderr);
358                                 fprintf(stderr, ") selects %s which has unmet direct dependencies (",
359                                         sym->name);
360                                 expr_fprint(sym->dir_dep.expr, stderr);
361                                 fprintf(stderr, ")\n");
362                                 expr_free(e);
363                         }
364                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
365                 }
366                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
367                         newval.tri = yes;
368                 break;
369         case S_STRING:
370         case S_HEX:
371         case S_INT:
372                 if (sym->visible != no) {
373                         sym->flags |= SYMBOL_WRITE;
374                         if (sym_has_value(sym)) {
375                                 newval.val = sym->def[S_DEF_USER].val;
376                                 break;
377                         }
378                 }
379                 prop = sym_get_default_prop(sym);
380                 if (prop) {
381                         struct symbol *ds = prop_get_symbol(prop);
382                         if (ds) {
383                                 sym->flags |= SYMBOL_WRITE;
384                                 sym_calc_value(ds);
385                                 newval.val = ds->curr.val;
386                         }
387                 }
388                 break;
389         default:
390                 ;
391         }
392
393         sym->curr = newval;
394         if (sym_is_choice(sym) && newval.tri == yes)
395                 sym->curr.val = sym_calc_choice(sym);
396         sym_validate_range(sym);
397
398         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
399                 sym_set_changed(sym);
400                 if (modules_sym == sym) {
401                         sym_set_all_changed();
402                         modules_val = modules_sym->curr.tri;
403                 }
404         }
405
406         if (sym_is_choice(sym)) {
407                 struct symbol *choice_sym;
408
409                 prop = sym_get_choice_prop(sym);
410                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
411                         if ((sym->flags & SYMBOL_WRITE) &&
412                             choice_sym->visible != no)
413                                 choice_sym->flags |= SYMBOL_WRITE;
414                         if (sym->flags & SYMBOL_CHANGED)
415                                 sym_set_changed(choice_sym);
416                 }
417         }
418
419         if (sym->flags & SYMBOL_AUTO)
420                 sym->flags &= ~SYMBOL_WRITE;
421 }
422
423 void sym_clear_all_valid(void)
424 {
425         struct symbol *sym;
426         int i;
427
428         for_all_symbols(i, sym)
429                 sym->flags &= ~SYMBOL_VALID;
430         sym_add_change_count(1);
431         if (modules_sym)
432                 sym_calc_value(modules_sym);
433 }
434
435 void sym_set_changed(struct symbol *sym)
436 {
437         struct property *prop;
438
439         sym->flags |= SYMBOL_CHANGED;
440         for (prop = sym->prop; prop; prop = prop->next) {
441                 if (prop->menu)
442                         prop->menu->flags |= MENU_CHANGED;
443         }
444 }
445
446 void sym_set_all_changed(void)
447 {
448         struct symbol *sym;
449         int i;
450
451         for_all_symbols(i, sym)
452                 sym_set_changed(sym);
453 }
454
455 bool sym_tristate_within_range(struct symbol *sym, tristate val)
456 {
457         int type = sym_get_type(sym);
458
459         if (sym->visible == no)
460                 return false;
461
462         if (type != S_BOOLEAN && type != S_TRISTATE)
463                 return false;
464
465         if (type == S_BOOLEAN && val == mod)
466                 return false;
467         if (sym->visible <= sym->rev_dep.tri)
468                 return false;
469         if (sym_is_choice_value(sym) && sym->visible == yes)
470                 return val == yes;
471         return val >= sym->rev_dep.tri && val <= sym->visible;
472 }
473
474 bool sym_set_tristate_value(struct symbol *sym, tristate val)
475 {
476         tristate oldval = sym_get_tristate_value(sym);
477
478         if (oldval != val && !sym_tristate_within_range(sym, val))
479                 return false;
480
481         if (!(sym->flags & SYMBOL_DEF_USER)) {
482                 sym->flags |= SYMBOL_DEF_USER;
483                 sym_set_changed(sym);
484         }
485         /*
486          * setting a choice value also resets the new flag of the choice
487          * symbol and all other choice values.
488          */
489         if (sym_is_choice_value(sym) && val == yes) {
490                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
491                 struct property *prop;
492                 struct expr *e;
493
494                 cs->def[S_DEF_USER].val = sym;
495                 cs->flags |= SYMBOL_DEF_USER;
496                 prop = sym_get_choice_prop(cs);
497                 for (e = prop->expr; e; e = e->left.expr) {
498                         if (e->right.sym->visible != no)
499                                 e->right.sym->flags |= SYMBOL_DEF_USER;
500                 }
501         }
502
503         sym->def[S_DEF_USER].tri = val;
504         if (oldval != val)
505                 sym_clear_all_valid();
506
507         return true;
508 }
509
510 tristate sym_toggle_tristate_value(struct symbol *sym)
511 {
512         tristate oldval, newval;
513
514         oldval = newval = sym_get_tristate_value(sym);
515         do {
516                 switch (newval) {
517                 case no:
518                         newval = mod;
519                         break;
520                 case mod:
521                         newval = yes;
522                         break;
523                 case yes:
524                         newval = no;
525                         break;
526                 }
527                 if (sym_set_tristate_value(sym, newval))
528                         break;
529         } while (oldval != newval);
530         return newval;
531 }
532
533 bool sym_string_valid(struct symbol *sym, const char *str)
534 {
535         signed char ch;
536
537         switch (sym->type) {
538         case S_STRING:
539                 return true;
540         case S_INT:
541                 ch = *str++;
542                 if (ch == '-')
543                         ch = *str++;
544                 if (!isdigit(ch))
545                         return false;
546                 if (ch == '0' && *str != 0)
547                         return false;
548                 while ((ch = *str++)) {
549                         if (!isdigit(ch))
550                                 return false;
551                 }
552                 return true;
553         case S_HEX:
554                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
555                         str += 2;
556                 ch = *str++;
557                 do {
558                         if (!isxdigit(ch))
559                                 return false;
560                 } while ((ch = *str++));
561                 return true;
562         case S_BOOLEAN:
563         case S_TRISTATE:
564                 switch (str[0]) {
565                 case 'y': case 'Y':
566                 case 'm': case 'M':
567                 case 'n': case 'N':
568                         return true;
569                 }
570                 return false;
571         default:
572                 return false;
573         }
574 }
575
576 bool sym_string_within_range(struct symbol *sym, const char *str)
577 {
578         struct property *prop;
579         int val;
580
581         switch (sym->type) {
582         case S_STRING:
583                 return sym_string_valid(sym, str);
584         case S_INT:
585                 if (!sym_string_valid(sym, str))
586                         return false;
587                 prop = sym_get_range_prop(sym);
588                 if (!prop)
589                         return true;
590                 val = strtol(str, NULL, 10);
591                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
592                        val <= sym_get_range_val(prop->expr->right.sym, 10);
593         case S_HEX:
594                 if (!sym_string_valid(sym, str))
595                         return false;
596                 prop = sym_get_range_prop(sym);
597                 if (!prop)
598                         return true;
599                 val = strtol(str, NULL, 16);
600                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
601                        val <= sym_get_range_val(prop->expr->right.sym, 16);
602         case S_BOOLEAN:
603         case S_TRISTATE:
604                 switch (str[0]) {
605                 case 'y': case 'Y':
606                         return sym_tristate_within_range(sym, yes);
607                 case 'm': case 'M':
608                         return sym_tristate_within_range(sym, mod);
609                 case 'n': case 'N':
610                         return sym_tristate_within_range(sym, no);
611                 }
612                 return false;
613         default:
614                 return false;
615         }
616 }
617
618 bool sym_set_string_value(struct symbol *sym, const char *newval)
619 {
620         const char *oldval;
621         char *val;
622         int size;
623
624         switch (sym->type) {
625         case S_BOOLEAN:
626         case S_TRISTATE:
627                 switch (newval[0]) {
628                 case 'y': case 'Y':
629                         return sym_set_tristate_value(sym, yes);
630                 case 'm': case 'M':
631                         return sym_set_tristate_value(sym, mod);
632                 case 'n': case 'N':
633                         return sym_set_tristate_value(sym, no);
634                 }
635                 return false;
636         default:
637                 ;
638         }
639
640         if (!sym_string_within_range(sym, newval))
641                 return false;
642
643         if (!(sym->flags & SYMBOL_DEF_USER)) {
644                 sym->flags |= SYMBOL_DEF_USER;
645                 sym_set_changed(sym);
646         }
647
648         oldval = sym->def[S_DEF_USER].val;
649         size = strlen(newval) + 1;
650         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
651                 size += 2;
652                 sym->def[S_DEF_USER].val = val = malloc(size);
653                 *val++ = '0';
654                 *val++ = 'x';
655         } else if (!oldval || strcmp(oldval, newval))
656                 sym->def[S_DEF_USER].val = val = malloc(size);
657         else
658                 return true;
659
660         strcpy(val, newval);
661         free((void *)oldval);
662         sym_clear_all_valid();
663
664         return true;
665 }
666
667 /*
668  * Find the default value associated to a symbol.
669  * For tristate symbol handle the modules=n case
670  * in which case "m" becomes "y".
671  * If the symbol does not have any default then fallback
672  * to the fixed default values.
673  */
674 const char *sym_get_string_default(struct symbol *sym)
675 {
676         struct property *prop;
677         struct symbol *ds;
678         const char *str;
679         tristate val;
680
681         sym_calc_visibility(sym);
682         sym_calc_value(modules_sym);
683         val = symbol_no.curr.tri;
684         str = symbol_empty.curr.val;
685
686         /* If symbol has a default value look it up */
687         prop = sym_get_default_prop(sym);
688         if (prop != NULL) {
689                 switch (sym->type) {
690                 case S_BOOLEAN:
691                 case S_TRISTATE:
692                         /* The visibility may limit the value from yes => mod */
693                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
694                         break;
695                 default:
696                         /*
697                          * The following fails to handle the situation
698                          * where a default value is further limited by
699                          * the valid range.
700                          */
701                         ds = prop_get_symbol(prop);
702                         if (ds != NULL) {
703                                 sym_calc_value(ds);
704                                 str = (const char *)ds->curr.val;
705                         }
706                 }
707         }
708
709         /* Handle select statements */
710         val = EXPR_OR(val, sym->rev_dep.tri);
711
712         /* transpose mod to yes if modules are not enabled */
713         if (val == mod)
714                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
715                         val = yes;
716
717         /* transpose mod to yes if type is bool */
718         if (sym->type == S_BOOLEAN && val == mod)
719                 val = yes;
720
721         switch (sym->type) {
722         case S_BOOLEAN:
723         case S_TRISTATE:
724                 switch (val) {
725                 case no: return "n";
726                 case mod: return "m";
727                 case yes: return "y";
728                 }
729         case S_INT:
730         case S_HEX:
731                 return str;
732         case S_STRING:
733                 return str;
734         case S_OTHER:
735         case S_UNKNOWN:
736                 break;
737         }
738         return "";
739 }
740
741 const char *sym_get_string_value(struct symbol *sym)
742 {
743         tristate val;
744
745         switch (sym->type) {
746         case S_BOOLEAN:
747         case S_TRISTATE:
748                 val = sym_get_tristate_value(sym);
749                 switch (val) {
750                 case no:
751                         return "n";
752                 case mod:
753                         return "m";
754                 case yes:
755                         return "y";
756                 }
757                 break;
758         default:
759                 ;
760         }
761         return (const char *)sym->curr.val;
762 }
763
764 bool sym_is_changable(struct symbol *sym)
765 {
766         return sym->visible > sym->rev_dep.tri;
767 }
768
769 static unsigned strhash(const char *s)
770 {
771         /* fnv32 hash */
772         unsigned hash = 2166136261U;
773         for (; *s; s++)
774                 hash = (hash ^ *s) * 0x01000193;
775         return hash;
776 }
777
778 struct symbol *sym_lookup(const char *name, int flags)
779 {
780         struct symbol *symbol;
781         char *new_name;
782         int hash;
783
784         if (name) {
785                 if (name[0] && !name[1]) {
786                         switch (name[0]) {
787                         case 'y': return &symbol_yes;
788                         case 'm': return &symbol_mod;
789                         case 'n': return &symbol_no;
790                         }
791                 }
792                 hash = strhash(name) % SYMBOL_HASHSIZE;
793
794                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
795                         if (symbol->name &&
796                             !strcmp(symbol->name, name) &&
797                             (flags ? symbol->flags & flags
798                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
799                                 return symbol;
800                 }
801                 new_name = strdup(name);
802         } else {
803                 new_name = NULL;
804                 hash = 0;
805         }
806
807         symbol = malloc(sizeof(*symbol));
808         memset(symbol, 0, sizeof(*symbol));
809         symbol->name = new_name;
810         symbol->type = S_UNKNOWN;
811         symbol->flags |= flags;
812
813         symbol->next = symbol_hash[hash];
814         symbol_hash[hash] = symbol;
815
816         return symbol;
817 }
818
819 struct symbol *sym_find(const char *name)
820 {
821         struct symbol *symbol = NULL;
822         int hash = 0;
823
824         if (!name)
825                 return NULL;
826
827         if (name[0] && !name[1]) {
828                 switch (name[0]) {
829                 case 'y': return &symbol_yes;
830                 case 'm': return &symbol_mod;
831                 case 'n': return &symbol_no;
832                 }
833         }
834         hash = strhash(name) % SYMBOL_HASHSIZE;
835
836         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
837                 if (symbol->name &&
838                     !strcmp(symbol->name, name) &&
839                     !(symbol->flags & SYMBOL_CONST))
840                                 break;
841         }
842
843         return symbol;
844 }
845
846 /*
847  * Expand symbol's names embedded in the string given in argument. Symbols'
848  * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
849  * the empty string.
850  */
851 const char *sym_expand_string_value(const char *in)
852 {
853         const char *src;
854         char *res;
855         size_t reslen;
856
857         reslen = strlen(in) + 1;
858         res = malloc(reslen);
859         res[0] = '\0';
860
861         while ((src = strchr(in, '$'))) {
862                 char *p, name[SYMBOL_MAXLENGTH];
863                 const char *symval = "";
864                 struct symbol *sym;
865                 size_t newlen;
866
867                 strncat(res, in, src - in);
868                 src++;
869
870                 p = name;
871                 while (isalnum(*src) || *src == '_')
872                         *p++ = *src++;
873                 *p = '\0';
874
875                 sym = sym_find(name);
876                 if (sym != NULL) {
877                         sym_calc_value(sym);
878                         symval = sym_get_string_value(sym);
879                 }
880
881                 newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
882                 if (newlen > reslen) {
883                         reslen = newlen;
884                         res = realloc(res, reslen);
885                 }
886
887                 strcat(res, symval);
888                 in = src;
889         }
890         strcat(res, in);
891
892         return res;
893 }
894
895 struct symbol **sym_re_search(const char *pattern)
896 {
897         struct symbol *sym, **sym_arr = NULL;
898         int i, cnt, size;
899         regex_t re;
900
901         cnt = size = 0;
902         /* Skip if empty */
903         if (strlen(pattern) == 0)
904                 return NULL;
905         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
906                 return NULL;
907
908         for_all_symbols(i, sym) {
909                 if (sym->flags & SYMBOL_CONST || !sym->name)
910                         continue;
911                 if (regexec(&re, sym->name, 0, NULL, 0))
912                         continue;
913                 if (cnt + 1 >= size) {
914                         void *tmp = sym_arr;
915                         size += 16;
916                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
917                         if (!sym_arr) {
918                                 free(tmp);
919                                 return NULL;
920                         }
921                 }
922                 sym_calc_value(sym);
923                 sym_arr[cnt++] = sym;
924         }
925         if (sym_arr)
926                 sym_arr[cnt] = NULL;
927         regfree(&re);
928
929         return sym_arr;
930 }
931
932 /*
933  * When we check for recursive dependencies we use a stack to save
934  * current state so we can print out relevant info to user.
935  * The entries are located on the call stack so no need to free memory.
936  * Note inser() remove() must always match to properly clear the stack.
937  */
938 static struct dep_stack {
939         struct dep_stack *prev, *next;
940         struct symbol *sym;
941         struct property *prop;
942         struct expr *expr;
943 } *check_top;
944
945 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
946 {
947         memset(stack, 0, sizeof(*stack));
948         if (check_top)
949                 check_top->next = stack;
950         stack->prev = check_top;
951         stack->sym = sym;
952         check_top = stack;
953 }
954
955 static void dep_stack_remove(void)
956 {
957         check_top = check_top->prev;
958         if (check_top)
959                 check_top->next = NULL;
960 }
961
962 /*
963  * Called when we have detected a recursive dependency.
964  * check_top point to the top of the stact so we use
965  * the ->prev pointer to locate the bottom of the stack.
966  */
967 static void sym_check_print_recursive(struct symbol *last_sym)
968 {
969         struct dep_stack *stack;
970         struct symbol *sym, *next_sym;
971         struct menu *menu = NULL;
972         struct property *prop;
973         struct dep_stack cv_stack;
974
975         if (sym_is_choice_value(last_sym)) {
976                 dep_stack_insert(&cv_stack, last_sym);
977                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
978         }
979
980         for (stack = check_top; stack != NULL; stack = stack->prev)
981                 if (stack->sym == last_sym)
982                         break;
983         if (!stack) {
984                 fprintf(stderr, "unexpected recursive dependency error\n");
985                 return;
986         }
987
988         for (; stack; stack = stack->next) {
989                 sym = stack->sym;
990                 next_sym = stack->next ? stack->next->sym : last_sym;
991                 prop = stack->prop;
992                 if (prop == NULL)
993                         prop = stack->sym->prop;
994
995                 /* for choice values find the menu entry (used below) */
996                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
997                         for (prop = sym->prop; prop; prop = prop->next) {
998                                 menu = prop->menu;
999                                 if (prop->menu)
1000                                         break;
1001                         }
1002                 }
1003                 if (stack->sym == last_sym)
1004                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1005                                 prop->file->name, prop->lineno);
1006                 if (stack->expr) {
1007                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1008                                 prop->file->name, prop->lineno,
1009                                 sym->name ? sym->name : "<choice>",
1010                                 prop_get_type_name(prop->type),
1011                                 next_sym->name ? next_sym->name : "<choice>");
1012                 } else if (stack->prop) {
1013                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1014                                 prop->file->name, prop->lineno,
1015                                 sym->name ? sym->name : "<choice>",
1016                                 next_sym->name ? next_sym->name : "<choice>");
1017                 } else if (sym_is_choice(sym)) {
1018                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1019                                 menu->file->name, menu->lineno,
1020                                 sym->name ? sym->name : "<choice>",
1021                                 next_sym->name ? next_sym->name : "<choice>");
1022                 } else if (sym_is_choice_value(sym)) {
1023                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1024                                 menu->file->name, menu->lineno,
1025                                 sym->name ? sym->name : "<choice>",
1026                                 next_sym->name ? next_sym->name : "<choice>");
1027                 } else {
1028                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1029                                 prop->file->name, prop->lineno,
1030                                 sym->name ? sym->name : "<choice>",
1031                                 next_sym->name ? next_sym->name : "<choice>");
1032                 }
1033         }
1034
1035         if (check_top == &cv_stack)
1036                 dep_stack_remove();
1037 }
1038
1039 static struct symbol *sym_check_expr_deps(struct expr *e)
1040 {
1041         struct symbol *sym;
1042
1043         if (!e)
1044                 return NULL;
1045         switch (e->type) {
1046         case E_OR:
1047         case E_AND:
1048                 sym = sym_check_expr_deps(e->left.expr);
1049                 if (sym)
1050                         return sym;
1051                 return sym_check_expr_deps(e->right.expr);
1052         case E_NOT:
1053                 return sym_check_expr_deps(e->left.expr);
1054         case E_EQUAL:
1055         case E_UNEQUAL:
1056                 sym = sym_check_deps(e->left.sym);
1057                 if (sym)
1058                         return sym;
1059                 return sym_check_deps(e->right.sym);
1060         case E_SYMBOL:
1061                 return sym_check_deps(e->left.sym);
1062         default:
1063                 break;
1064         }
1065         printf("Oops! How to check %d?\n", e->type);
1066         return NULL;
1067 }
1068
1069 /* return NULL when dependencies are OK */
1070 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1071 {
1072         struct symbol *sym2;
1073         struct property *prop;
1074         struct dep_stack stack;
1075
1076         dep_stack_insert(&stack, sym);
1077
1078         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1079         if (sym2)
1080                 goto out;
1081
1082         for (prop = sym->prop; prop; prop = prop->next) {
1083                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1084                         continue;
1085                 stack.prop = prop;
1086                 sym2 = sym_check_expr_deps(prop->visible.expr);
1087                 if (sym2)
1088                         break;
1089                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1090                         continue;
1091                 stack.expr = prop->expr;
1092                 sym2 = sym_check_expr_deps(prop->expr);
1093                 if (sym2)
1094                         break;
1095                 stack.expr = NULL;
1096         }
1097
1098 out:
1099         dep_stack_remove();
1100
1101         return sym2;
1102 }
1103
1104 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1105 {
1106         struct symbol *sym, *sym2;
1107         struct property *prop;
1108         struct expr *e;
1109         struct dep_stack stack;
1110
1111         dep_stack_insert(&stack, choice);
1112
1113         prop = sym_get_choice_prop(choice);
1114         expr_list_for_each_sym(prop->expr, e, sym)
1115                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1116
1117         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1118         sym2 = sym_check_sym_deps(choice);
1119         choice->flags &= ~SYMBOL_CHECK;
1120         if (sym2)
1121                 goto out;
1122
1123         expr_list_for_each_sym(prop->expr, e, sym) {
1124                 sym2 = sym_check_sym_deps(sym);
1125                 if (sym2)
1126                         break;
1127         }
1128 out:
1129         expr_list_for_each_sym(prop->expr, e, sym)
1130                 sym->flags &= ~SYMBOL_CHECK;
1131
1132         if (sym2 && sym_is_choice_value(sym2) &&
1133             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1134                 sym2 = choice;
1135
1136         dep_stack_remove();
1137
1138         return sym2;
1139 }
1140
1141 struct symbol *sym_check_deps(struct symbol *sym)
1142 {
1143         struct symbol *sym2;
1144         struct property *prop;
1145
1146         if (sym->flags & SYMBOL_CHECK) {
1147                 sym_check_print_recursive(sym);
1148                 return sym;
1149         }
1150         if (sym->flags & SYMBOL_CHECKED)
1151                 return NULL;
1152
1153         if (sym_is_choice_value(sym)) {
1154                 struct dep_stack stack;
1155
1156                 /* for choice groups start the check with main choice symbol */
1157                 dep_stack_insert(&stack, sym);
1158                 prop = sym_get_choice_prop(sym);
1159                 sym2 = sym_check_deps(prop_get_symbol(prop));
1160                 dep_stack_remove();
1161         } else if (sym_is_choice(sym)) {
1162                 sym2 = sym_check_choice_deps(sym);
1163         } else {
1164                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1165                 sym2 = sym_check_sym_deps(sym);
1166                 sym->flags &= ~SYMBOL_CHECK;
1167         }
1168
1169         if (sym2 && sym2 == sym)
1170                 sym2 = NULL;
1171
1172         return sym2;
1173 }
1174
1175 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1176 {
1177         struct property *prop;
1178         struct property **propp;
1179
1180         prop = malloc(sizeof(*prop));
1181         memset(prop, 0, sizeof(*prop));
1182         prop->type = type;
1183         prop->sym = sym;
1184         prop->file = current_file;
1185         prop->lineno = zconf_lineno();
1186
1187         /* append property to the prop list of symbol */
1188         if (sym) {
1189                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1190                         ;
1191                 *propp = prop;
1192         }
1193
1194         return prop;
1195 }
1196
1197 struct symbol *prop_get_symbol(struct property *prop)
1198 {
1199         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1200                            prop->expr->type == E_LIST))
1201                 return prop->expr->left.sym;
1202         return NULL;
1203 }
1204
1205 const char *prop_get_type_name(enum prop_type type)
1206 {
1207         switch (type) {
1208         case P_PROMPT:
1209                 return "prompt";
1210         case P_ENV:
1211                 return "env";
1212         case P_COMMENT:
1213                 return "comment";
1214         case P_MENU:
1215                 return "menu";
1216         case P_DEFAULT:
1217                 return "default";
1218         case P_CHOICE:
1219                 return "choice";
1220         case P_SELECT:
1221                 return "select";
1222         case P_RANGE:
1223                 return "range";
1224         case P_SYMBOL:
1225                 return "symbol";
1226         case P_UNKNOWN:
1227                 break;
1228         }
1229         return "unknown";
1230 }
1231
1232 static void prop_add_env(const char *env)
1233 {
1234         struct symbol *sym, *sym2;
1235         struct property *prop;
1236         char *p;
1237
1238         sym = current_entry->sym;
1239         sym->flags |= SYMBOL_AUTO;
1240         for_all_properties(sym, prop, P_ENV) {
1241                 sym2 = prop_get_symbol(prop);
1242                 if (strcmp(sym2->name, env))
1243                         menu_warn(current_entry, "redefining environment symbol from %s",
1244                                   sym2->name);
1245                 return;
1246         }
1247
1248         prop = prop_alloc(P_ENV, sym);
1249         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1250
1251         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1252         sym_env_list->right.sym = sym;
1253
1254         p = getenv(env);
1255         if (p)
1256                 sym_add_default(sym, p);
1257         else
1258                 menu_warn(current_entry, "environment variable %s undefined", env);
1259 }