Merge branch 'kvm-updates-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / 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 #define LKC_DIRECT_LINK
13 #include "lkc.h"
14
15 struct symbol symbol_yes = {
16         .name = "y",
17         .curr = { "y", yes },
18         .flags = SYMBOL_CONST|SYMBOL_VALID,
19 }, symbol_mod = {
20         .name = "m",
21         .curr = { "m", mod },
22         .flags = SYMBOL_CONST|SYMBOL_VALID,
23 }, symbol_no = {
24         .name = "n",
25         .curr = { "n", no },
26         .flags = SYMBOL_CONST|SYMBOL_VALID,
27 }, symbol_empty = {
28         .name = "",
29         .curr = { "", no },
30         .flags = SYMBOL_VALID,
31 };
32
33 struct symbol *sym_defconfig_list;
34 struct symbol *modules_sym;
35 tristate modules_val;
36
37 struct expr *sym_env_list;
38
39 void sym_add_default(struct symbol *sym, const char *def)
40 {
41         struct property *prop = prop_alloc(P_DEFAULT, sym);
42
43         prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST));
44 }
45
46 void sym_init(void)
47 {
48         struct symbol *sym;
49         struct utsname uts;
50         static bool inited = false;
51
52         if (inited)
53                 return;
54         inited = true;
55
56         uname(&uts);
57
58         sym = sym_lookup("UNAME_RELEASE", 0);
59         sym->type = S_STRING;
60         sym->flags |= SYMBOL_AUTO;
61         sym_add_default(sym, uts.release);
62 }
63
64 enum symbol_type sym_get_type(struct symbol *sym)
65 {
66         enum symbol_type type = sym->type;
67
68         if (type == S_TRISTATE) {
69                 if (sym_is_choice_value(sym) && sym->visible == yes)
70                         type = S_BOOLEAN;
71                 else if (modules_val == no)
72                         type = S_BOOLEAN;
73         }
74         return type;
75 }
76
77 const char *sym_type_name(enum symbol_type type)
78 {
79         switch (type) {
80         case S_BOOLEAN:
81                 return "boolean";
82         case S_TRISTATE:
83                 return "tristate";
84         case S_INT:
85                 return "integer";
86         case S_HEX:
87                 return "hex";
88         case S_STRING:
89                 return "string";
90         case S_UNKNOWN:
91                 return "unknown";
92         case S_OTHER:
93                 break;
94         }
95         return "???";
96 }
97
98 struct property *sym_get_choice_prop(struct symbol *sym)
99 {
100         struct property *prop;
101
102         for_all_choices(sym, prop)
103                 return prop;
104         return NULL;
105 }
106
107 struct property *sym_get_env_prop(struct symbol *sym)
108 {
109         struct property *prop;
110
111         for_all_properties(sym, prop, P_ENV)
112                 return prop;
113         return NULL;
114 }
115
116 struct property *sym_get_default_prop(struct symbol *sym)
117 {
118         struct property *prop;
119
120         for_all_defaults(sym, prop) {
121                 prop->visible.tri = expr_calc_value(prop->visible.expr);
122                 if (prop->visible.tri != no)
123                         return prop;
124         }
125         return NULL;
126 }
127
128 struct property *sym_get_range_prop(struct symbol *sym)
129 {
130         struct property *prop;
131
132         for_all_properties(sym, prop, P_RANGE) {
133                 prop->visible.tri = expr_calc_value(prop->visible.expr);
134                 if (prop->visible.tri != no)
135                         return prop;
136         }
137         return NULL;
138 }
139
140 static int sym_get_range_val(struct symbol *sym, int base)
141 {
142         sym_calc_value(sym);
143         switch (sym->type) {
144         case S_INT:
145                 base = 10;
146                 break;
147         case S_HEX:
148                 base = 16;
149                 break;
150         default:
151                 break;
152         }
153         return strtol(sym->curr.val, NULL, base);
154 }
155
156 static void sym_validate_range(struct symbol *sym)
157 {
158         struct property *prop;
159         int base, 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 = strtol(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, "%d", val2);
184         else
185                 sprintf(str, "0x%x", 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         tri = no;
209         if (sym->rev_dep.expr)
210                 tri = expr_calc_value(sym->rev_dep.expr);
211         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
212                 tri = yes;
213         if (sym->rev_dep.tri != tri) {
214                 sym->rev_dep.tri = tri;
215                 sym_set_changed(sym);
216         }
217 }
218
219 static struct symbol *sym_calc_choice(struct symbol *sym)
220 {
221         struct symbol *def_sym;
222         struct property *prop;
223         struct expr *e;
224
225         /* is the user choice visible? */
226         def_sym = sym->def[S_DEF_USER].val;
227         if (def_sym) {
228                 sym_calc_visibility(def_sym);
229                 if (def_sym->visible != no)
230                         return def_sym;
231         }
232
233         /* any of the defaults visible? */
234         for_all_defaults(sym, prop) {
235                 prop->visible.tri = expr_calc_value(prop->visible.expr);
236                 if (prop->visible.tri == no)
237                         continue;
238                 def_sym = prop_get_symbol(prop);
239                 sym_calc_visibility(def_sym);
240                 if (def_sym->visible != no)
241                         return def_sym;
242         }
243
244         /* just get the first visible value */
245         prop = sym_get_choice_prop(sym);
246         expr_list_for_each_sym(prop->expr, e, def_sym) {
247                 sym_calc_visibility(def_sym);
248                 if (def_sym->visible != no)
249                         return def_sym;
250         }
251
252         /* no choice? reset tristate value */
253         sym->curr.tri = no;
254         return NULL;
255 }
256
257 void sym_calc_value(struct symbol *sym)
258 {
259         struct symbol_value newval, oldval;
260         struct property *prop;
261         struct expr *e;
262
263         if (!sym)
264                 return;
265
266         if (sym->flags & SYMBOL_VALID)
267                 return;
268         sym->flags |= SYMBOL_VALID;
269
270         oldval = sym->curr;
271
272         switch (sym->type) {
273         case S_INT:
274         case S_HEX:
275         case S_STRING:
276                 newval = symbol_empty.curr;
277                 break;
278         case S_BOOLEAN:
279         case S_TRISTATE:
280                 newval = symbol_no.curr;
281                 break;
282         default:
283                 sym->curr.val = sym->name;
284                 sym->curr.tri = no;
285                 return;
286         }
287         if (!sym_is_choice_value(sym))
288                 sym->flags &= ~SYMBOL_WRITE;
289
290         sym_calc_visibility(sym);
291
292         /* set default if recursively called */
293         sym->curr = newval;
294
295         switch (sym_get_type(sym)) {
296         case S_BOOLEAN:
297         case S_TRISTATE:
298                 if (sym_is_choice_value(sym) && sym->visible == yes) {
299                         prop = sym_get_choice_prop(sym);
300                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
301                 } else {
302                         if (sym->visible != no) {
303                                 /* if the symbol is visible use the user value
304                                  * if available, otherwise try the default value
305                                  */
306                                 sym->flags |= SYMBOL_WRITE;
307                                 if (sym_has_value(sym)) {
308                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
309                                                               sym->visible);
310                                         goto calc_newval;
311                                 }
312                         }
313                         if (sym->rev_dep.tri != no)
314                                 sym->flags |= SYMBOL_WRITE;
315                         if (!sym_is_choice(sym)) {
316                                 prop = sym_get_default_prop(sym);
317                                 if (prop) {
318                                         sym->flags |= SYMBOL_WRITE;
319                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
320                                                               prop->visible.tri);
321                                 }
322                         }
323                 calc_newval:
324                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
325                 }
326                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
327                         newval.tri = yes;
328                 break;
329         case S_STRING:
330         case S_HEX:
331         case S_INT:
332                 if (sym->visible != no) {
333                         sym->flags |= SYMBOL_WRITE;
334                         if (sym_has_value(sym)) {
335                                 newval.val = sym->def[S_DEF_USER].val;
336                                 break;
337                         }
338                 }
339                 prop = sym_get_default_prop(sym);
340                 if (prop) {
341                         struct symbol *ds = prop_get_symbol(prop);
342                         if (ds) {
343                                 sym->flags |= SYMBOL_WRITE;
344                                 sym_calc_value(ds);
345                                 newval.val = ds->curr.val;
346                         }
347                 }
348                 break;
349         default:
350                 ;
351         }
352
353         sym->curr = newval;
354         if (sym_is_choice(sym) && newval.tri == yes)
355                 sym->curr.val = sym_calc_choice(sym);
356         sym_validate_range(sym);
357
358         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
359                 sym_set_changed(sym);
360                 if (modules_sym == sym) {
361                         sym_set_all_changed();
362                         modules_val = modules_sym->curr.tri;
363                 }
364         }
365
366         if (sym_is_choice(sym)) {
367                 struct symbol *choice_sym;
368                 int flags = sym->flags & (SYMBOL_CHANGED | SYMBOL_WRITE);
369
370                 prop = sym_get_choice_prop(sym);
371                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
372                         choice_sym->flags |= flags;
373                         if (flags & SYMBOL_CHANGED)
374                                 sym_set_changed(choice_sym);
375                 }
376         }
377
378         if (sym->flags & SYMBOL_AUTO)
379                 sym->flags &= ~SYMBOL_WRITE;
380 }
381
382 void sym_clear_all_valid(void)
383 {
384         struct symbol *sym;
385         int i;
386
387         for_all_symbols(i, sym)
388                 sym->flags &= ~SYMBOL_VALID;
389         sym_add_change_count(1);
390         if (modules_sym)
391                 sym_calc_value(modules_sym);
392 }
393
394 void sym_set_changed(struct symbol *sym)
395 {
396         struct property *prop;
397
398         sym->flags |= SYMBOL_CHANGED;
399         for (prop = sym->prop; prop; prop = prop->next) {
400                 if (prop->menu)
401                         prop->menu->flags |= MENU_CHANGED;
402         }
403 }
404
405 void sym_set_all_changed(void)
406 {
407         struct symbol *sym;
408         int i;
409
410         for_all_symbols(i, sym)
411                 sym_set_changed(sym);
412 }
413
414 bool sym_tristate_within_range(struct symbol *sym, tristate val)
415 {
416         int type = sym_get_type(sym);
417
418         if (sym->visible == no)
419                 return false;
420
421         if (type != S_BOOLEAN && type != S_TRISTATE)
422                 return false;
423
424         if (type == S_BOOLEAN && val == mod)
425                 return false;
426         if (sym->visible <= sym->rev_dep.tri)
427                 return false;
428         if (sym_is_choice_value(sym) && sym->visible == yes)
429                 return val == yes;
430         return val >= sym->rev_dep.tri && val <= sym->visible;
431 }
432
433 bool sym_set_tristate_value(struct symbol *sym, tristate val)
434 {
435         tristate oldval = sym_get_tristate_value(sym);
436
437         if (oldval != val && !sym_tristate_within_range(sym, val))
438                 return false;
439
440         if (!(sym->flags & SYMBOL_DEF_USER)) {
441                 sym->flags |= SYMBOL_DEF_USER;
442                 sym_set_changed(sym);
443         }
444         /*
445          * setting a choice value also resets the new flag of the choice
446          * symbol and all other choice values.
447          */
448         if (sym_is_choice_value(sym) && val == yes) {
449                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
450                 struct property *prop;
451                 struct expr *e;
452
453                 cs->def[S_DEF_USER].val = sym;
454                 cs->flags |= SYMBOL_DEF_USER;
455                 prop = sym_get_choice_prop(cs);
456                 for (e = prop->expr; e; e = e->left.expr) {
457                         if (e->right.sym->visible != no)
458                                 e->right.sym->flags |= SYMBOL_DEF_USER;
459                 }
460         }
461
462         sym->def[S_DEF_USER].tri = val;
463         if (oldval != val)
464                 sym_clear_all_valid();
465
466         return true;
467 }
468
469 tristate sym_toggle_tristate_value(struct symbol *sym)
470 {
471         tristate oldval, newval;
472
473         oldval = newval = sym_get_tristate_value(sym);
474         do {
475                 switch (newval) {
476                 case no:
477                         newval = mod;
478                         break;
479                 case mod:
480                         newval = yes;
481                         break;
482                 case yes:
483                         newval = no;
484                         break;
485                 }
486                 if (sym_set_tristate_value(sym, newval))
487                         break;
488         } while (oldval != newval);
489         return newval;
490 }
491
492 bool sym_string_valid(struct symbol *sym, const char *str)
493 {
494         signed char ch;
495
496         switch (sym->type) {
497         case S_STRING:
498                 return true;
499         case S_INT:
500                 ch = *str++;
501                 if (ch == '-')
502                         ch = *str++;
503                 if (!isdigit(ch))
504                         return false;
505                 if (ch == '0' && *str != 0)
506                         return false;
507                 while ((ch = *str++)) {
508                         if (!isdigit(ch))
509                                 return false;
510                 }
511                 return true;
512         case S_HEX:
513                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
514                         str += 2;
515                 ch = *str++;
516                 do {
517                         if (!isxdigit(ch))
518                                 return false;
519                 } while ((ch = *str++));
520                 return true;
521         case S_BOOLEAN:
522         case S_TRISTATE:
523                 switch (str[0]) {
524                 case 'y': case 'Y':
525                 case 'm': case 'M':
526                 case 'n': case 'N':
527                         return true;
528                 }
529                 return false;
530         default:
531                 return false;
532         }
533 }
534
535 bool sym_string_within_range(struct symbol *sym, const char *str)
536 {
537         struct property *prop;
538         int val;
539
540         switch (sym->type) {
541         case S_STRING:
542                 return sym_string_valid(sym, str);
543         case S_INT:
544                 if (!sym_string_valid(sym, str))
545                         return false;
546                 prop = sym_get_range_prop(sym);
547                 if (!prop)
548                         return true;
549                 val = strtol(str, NULL, 10);
550                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
551                        val <= sym_get_range_val(prop->expr->right.sym, 10);
552         case S_HEX:
553                 if (!sym_string_valid(sym, str))
554                         return false;
555                 prop = sym_get_range_prop(sym);
556                 if (!prop)
557                         return true;
558                 val = strtol(str, NULL, 16);
559                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
560                        val <= sym_get_range_val(prop->expr->right.sym, 16);
561         case S_BOOLEAN:
562         case S_TRISTATE:
563                 switch (str[0]) {
564                 case 'y': case 'Y':
565                         return sym_tristate_within_range(sym, yes);
566                 case 'm': case 'M':
567                         return sym_tristate_within_range(sym, mod);
568                 case 'n': case 'N':
569                         return sym_tristate_within_range(sym, no);
570                 }
571                 return false;
572         default:
573                 return false;
574         }
575 }
576
577 bool sym_set_string_value(struct symbol *sym, const char *newval)
578 {
579         const char *oldval;
580         char *val;
581         int size;
582
583         switch (sym->type) {
584         case S_BOOLEAN:
585         case S_TRISTATE:
586                 switch (newval[0]) {
587                 case 'y': case 'Y':
588                         return sym_set_tristate_value(sym, yes);
589                 case 'm': case 'M':
590                         return sym_set_tristate_value(sym, mod);
591                 case 'n': case 'N':
592                         return sym_set_tristate_value(sym, no);
593                 }
594                 return false;
595         default:
596                 ;
597         }
598
599         if (!sym_string_within_range(sym, newval))
600                 return false;
601
602         if (!(sym->flags & SYMBOL_DEF_USER)) {
603                 sym->flags |= SYMBOL_DEF_USER;
604                 sym_set_changed(sym);
605         }
606
607         oldval = sym->def[S_DEF_USER].val;
608         size = strlen(newval) + 1;
609         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
610                 size += 2;
611                 sym->def[S_DEF_USER].val = val = malloc(size);
612                 *val++ = '0';
613                 *val++ = 'x';
614         } else if (!oldval || strcmp(oldval, newval))
615                 sym->def[S_DEF_USER].val = val = malloc(size);
616         else
617                 return true;
618
619         strcpy(val, newval);
620         free((void *)oldval);
621         sym_clear_all_valid();
622
623         return true;
624 }
625
626 const char *sym_get_string_value(struct symbol *sym)
627 {
628         tristate val;
629
630         switch (sym->type) {
631         case S_BOOLEAN:
632         case S_TRISTATE:
633                 val = sym_get_tristate_value(sym);
634                 switch (val) {
635                 case no:
636                         return "n";
637                 case mod:
638                         return "m";
639                 case yes:
640                         return "y";
641                 }
642                 break;
643         default:
644                 ;
645         }
646         return (const char *)sym->curr.val;
647 }
648
649 bool sym_is_changable(struct symbol *sym)
650 {
651         return sym->visible > sym->rev_dep.tri;
652 }
653
654 struct symbol *sym_lookup(const char *name, int flags)
655 {
656         struct symbol *symbol;
657         const char *ptr;
658         char *new_name;
659         int hash = 0;
660
661         if (name) {
662                 if (name[0] && !name[1]) {
663                         switch (name[0]) {
664                         case 'y': return &symbol_yes;
665                         case 'm': return &symbol_mod;
666                         case 'n': return &symbol_no;
667                         }
668                 }
669                 for (ptr = name; *ptr; ptr++)
670                         hash += *ptr;
671                 hash &= 0xff;
672
673                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
674                         if (!strcmp(symbol->name, name) &&
675                             (flags ? symbol->flags & flags
676                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
677                                 return symbol;
678                 }
679                 new_name = strdup(name);
680         } else {
681                 new_name = NULL;
682                 hash = 256;
683         }
684
685         symbol = malloc(sizeof(*symbol));
686         memset(symbol, 0, sizeof(*symbol));
687         symbol->name = new_name;
688         symbol->type = S_UNKNOWN;
689         symbol->flags |= flags;
690
691         symbol->next = symbol_hash[hash];
692         symbol_hash[hash] = symbol;
693
694         return symbol;
695 }
696
697 struct symbol *sym_find(const char *name)
698 {
699         struct symbol *symbol = NULL;
700         const char *ptr;
701         int hash = 0;
702
703         if (!name)
704                 return NULL;
705
706         if (name[0] && !name[1]) {
707                 switch (name[0]) {
708                 case 'y': return &symbol_yes;
709                 case 'm': return &symbol_mod;
710                 case 'n': return &symbol_no;
711                 }
712         }
713         for (ptr = name; *ptr; ptr++)
714                 hash += *ptr;
715         hash &= 0xff;
716
717         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
718                 if (!strcmp(symbol->name, name) &&
719                     !(symbol->flags & SYMBOL_CONST))
720                                 break;
721         }
722
723         return symbol;
724 }
725
726 struct symbol **sym_re_search(const char *pattern)
727 {
728         struct symbol *sym, **sym_arr = NULL;
729         int i, cnt, size;
730         regex_t re;
731
732         cnt = size = 0;
733         /* Skip if empty */
734         if (strlen(pattern) == 0)
735                 return NULL;
736         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
737                 return NULL;
738
739         for_all_symbols(i, sym) {
740                 if (sym->flags & SYMBOL_CONST || !sym->name)
741                         continue;
742                 if (regexec(&re, sym->name, 0, NULL, 0))
743                         continue;
744                 if (cnt + 1 >= size) {
745                         void *tmp = sym_arr;
746                         size += 16;
747                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
748                         if (!sym_arr) {
749                                 free(tmp);
750                                 return NULL;
751                         }
752                 }
753                 sym_arr[cnt++] = sym;
754         }
755         if (sym_arr)
756                 sym_arr[cnt] = NULL;
757         regfree(&re);
758
759         return sym_arr;
760 }
761
762
763 static struct symbol *sym_check_expr_deps(struct expr *e)
764 {
765         struct symbol *sym;
766
767         if (!e)
768                 return NULL;
769         switch (e->type) {
770         case E_OR:
771         case E_AND:
772                 sym = sym_check_expr_deps(e->left.expr);
773                 if (sym)
774                         return sym;
775                 return sym_check_expr_deps(e->right.expr);
776         case E_NOT:
777                 return sym_check_expr_deps(e->left.expr);
778         case E_EQUAL:
779         case E_UNEQUAL:
780                 sym = sym_check_deps(e->left.sym);
781                 if (sym)
782                         return sym;
783                 return sym_check_deps(e->right.sym);
784         case E_SYMBOL:
785                 return sym_check_deps(e->left.sym);
786         default:
787                 break;
788         }
789         printf("Oops! How to check %d?\n", e->type);
790         return NULL;
791 }
792
793 /* return NULL when dependencies are OK */
794 static struct symbol *sym_check_sym_deps(struct symbol *sym)
795 {
796         struct symbol *sym2;
797         struct property *prop;
798
799         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
800         if (sym2)
801                 return sym2;
802
803         for (prop = sym->prop; prop; prop = prop->next) {
804                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
805                         continue;
806                 sym2 = sym_check_expr_deps(prop->visible.expr);
807                 if (sym2)
808                         break;
809                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
810                         continue;
811                 sym2 = sym_check_expr_deps(prop->expr);
812                 if (sym2)
813                         break;
814         }
815
816         return sym2;
817 }
818
819 static struct symbol *sym_check_choice_deps(struct symbol *choice)
820 {
821         struct symbol *sym, *sym2;
822         struct property *prop;
823         struct expr *e;
824
825         prop = sym_get_choice_prop(choice);
826         expr_list_for_each_sym(prop->expr, e, sym)
827                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
828
829         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
830         sym2 = sym_check_sym_deps(choice);
831         choice->flags &= ~SYMBOL_CHECK;
832         if (sym2)
833                 goto out;
834
835         expr_list_for_each_sym(prop->expr, e, sym) {
836                 sym2 = sym_check_sym_deps(sym);
837                 if (sym2) {
838                         fprintf(stderr, " -> %s", sym->name);
839                         break;
840                 }
841         }
842 out:
843         expr_list_for_each_sym(prop->expr, e, sym)
844                 sym->flags &= ~SYMBOL_CHECK;
845
846         if (sym2 && sym_is_choice_value(sym2) &&
847             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
848                 sym2 = choice;
849
850         return sym2;
851 }
852
853 struct symbol *sym_check_deps(struct symbol *sym)
854 {
855         struct symbol *sym2;
856         struct property *prop;
857
858         if (sym->flags & SYMBOL_CHECK) {
859                 fprintf(stderr, "%s:%d:error: found recursive dependency: %s",
860                         sym->prop->file->name, sym->prop->lineno,
861                         sym->name ? sym->name : "<choice>");
862                 return sym;
863         }
864         if (sym->flags & SYMBOL_CHECKED)
865                 return NULL;
866
867         if (sym_is_choice_value(sym)) {
868                 /* for choice groups start the check with main choice symbol */
869                 prop = sym_get_choice_prop(sym);
870                 sym2 = sym_check_deps(prop_get_symbol(prop));
871         } else if (sym_is_choice(sym)) {
872                 sym2 = sym_check_choice_deps(sym);
873         } else {
874                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
875                 sym2 = sym_check_sym_deps(sym);
876                 sym->flags &= ~SYMBOL_CHECK;
877         }
878
879         if (sym2) {
880                 fprintf(stderr, " -> %s", sym->name ? sym->name : "<choice>");
881                 if (sym2 == sym) {
882                         fprintf(stderr, "\n");
883                         zconfnerrs++;
884                         sym2 = NULL;
885                 }
886         }
887
888         return sym2;
889 }
890
891 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
892 {
893         struct property *prop;
894         struct property **propp;
895
896         prop = malloc(sizeof(*prop));
897         memset(prop, 0, sizeof(*prop));
898         prop->type = type;
899         prop->sym = sym;
900         prop->file = current_file;
901         prop->lineno = zconf_lineno();
902
903         /* append property to the prop list of symbol */
904         if (sym) {
905                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
906                         ;
907                 *propp = prop;
908         }
909
910         return prop;
911 }
912
913 struct symbol *prop_get_symbol(struct property *prop)
914 {
915         if (prop->expr && (prop->expr->type == E_SYMBOL ||
916                            prop->expr->type == E_LIST))
917                 return prop->expr->left.sym;
918         return NULL;
919 }
920
921 const char *prop_get_type_name(enum prop_type type)
922 {
923         switch (type) {
924         case P_PROMPT:
925                 return "prompt";
926         case P_ENV:
927                 return "env";
928         case P_COMMENT:
929                 return "comment";
930         case P_MENU:
931                 return "menu";
932         case P_DEFAULT:
933                 return "default";
934         case P_CHOICE:
935                 return "choice";
936         case P_SELECT:
937                 return "select";
938         case P_RANGE:
939                 return "range";
940         case P_UNKNOWN:
941                 break;
942         }
943         return "unknown";
944 }
945
946 void prop_add_env(const char *env)
947 {
948         struct symbol *sym, *sym2;
949         struct property *prop;
950         char *p;
951
952         sym = current_entry->sym;
953         sym->flags |= SYMBOL_AUTO;
954         for_all_properties(sym, prop, P_ENV) {
955                 sym2 = prop_get_symbol(prop);
956                 if (strcmp(sym2->name, env))
957                         menu_warn(current_entry, "redefining environment symbol from %s",
958                                   sym2->name);
959                 return;
960         }
961
962         prop = prop_alloc(P_ENV, sym);
963         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
964
965         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
966         sym_env_list->right.sym = sym;
967
968         p = getenv(env);
969         if (p)
970                 sym_add_default(sym, p);
971         else
972                 menu_warn(current_entry, "environment variable %s undefined", env);
973 }