V4L/DVB (7219): zoran: Fix namespace conflicts with Zoran 'GPIO_MAX' enum
[sfrench/cifs-2.6.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 #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, 1));
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 if (EXPR_OR(sym->visible, sym->rev_dep.tri) != no) {
302                         sym->flags |= SYMBOL_WRITE;
303                         if (sym_has_value(sym))
304                                 newval.tri = sym->def[S_DEF_USER].tri;
305                         else if (!sym_is_choice(sym)) {
306                                 prop = sym_get_default_prop(sym);
307                                 if (prop)
308                                         newval.tri = expr_calc_value(prop->expr);
309                         }
310                         newval.tri = EXPR_OR(EXPR_AND(newval.tri, sym->visible), sym->rev_dep.tri);
311                 } else if (!sym_is_choice(sym)) {
312                         prop = sym_get_default_prop(sym);
313                         if (prop) {
314                                 sym->flags |= SYMBOL_WRITE;
315                                 newval.tri = expr_calc_value(prop->expr);
316                         }
317                 }
318                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
319                         newval.tri = yes;
320                 break;
321         case S_STRING:
322         case S_HEX:
323         case S_INT:
324                 if (sym->visible != no) {
325                         sym->flags |= SYMBOL_WRITE;
326                         if (sym_has_value(sym)) {
327                                 newval.val = sym->def[S_DEF_USER].val;
328                                 break;
329                         }
330                 }
331                 prop = sym_get_default_prop(sym);
332                 if (prop) {
333                         struct symbol *ds = prop_get_symbol(prop);
334                         if (ds) {
335                                 sym->flags |= SYMBOL_WRITE;
336                                 sym_calc_value(ds);
337                                 newval.val = ds->curr.val;
338                         }
339                 }
340                 break;
341         default:
342                 ;
343         }
344
345         if (sym->flags & SYMBOL_AUTO)
346                 sym->flags &= ~SYMBOL_WRITE;
347
348         sym->curr = newval;
349         if (sym_is_choice(sym) && newval.tri == yes)
350                 sym->curr.val = sym_calc_choice(sym);
351         sym_validate_range(sym);
352
353         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
354                 sym_set_changed(sym);
355                 if (modules_sym == sym) {
356                         sym_set_all_changed();
357                         modules_val = modules_sym->curr.tri;
358                 }
359         }
360
361         if (sym_is_choice(sym)) {
362                 struct symbol *choice_sym;
363                 int flags = sym->flags & (SYMBOL_CHANGED | SYMBOL_WRITE);
364
365                 prop = sym_get_choice_prop(sym);
366                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
367                         choice_sym->flags |= flags;
368                         if (flags & SYMBOL_CHANGED)
369                                 sym_set_changed(choice_sym);
370                 }
371         }
372 }
373
374 void sym_clear_all_valid(void)
375 {
376         struct symbol *sym;
377         int i;
378
379         for_all_symbols(i, sym)
380                 sym->flags &= ~SYMBOL_VALID;
381         sym_add_change_count(1);
382         if (modules_sym)
383                 sym_calc_value(modules_sym);
384 }
385
386 void sym_set_changed(struct symbol *sym)
387 {
388         struct property *prop;
389
390         sym->flags |= SYMBOL_CHANGED;
391         for (prop = sym->prop; prop; prop = prop->next) {
392                 if (prop->menu)
393                         prop->menu->flags |= MENU_CHANGED;
394         }
395 }
396
397 void sym_set_all_changed(void)
398 {
399         struct symbol *sym;
400         int i;
401
402         for_all_symbols(i, sym)
403                 sym_set_changed(sym);
404 }
405
406 bool sym_tristate_within_range(struct symbol *sym, tristate val)
407 {
408         int type = sym_get_type(sym);
409
410         if (sym->visible == no)
411                 return false;
412
413         if (type != S_BOOLEAN && type != S_TRISTATE)
414                 return false;
415
416         if (type == S_BOOLEAN && val == mod)
417                 return false;
418         if (sym->visible <= sym->rev_dep.tri)
419                 return false;
420         if (sym_is_choice_value(sym) && sym->visible == yes)
421                 return val == yes;
422         return val >= sym->rev_dep.tri && val <= sym->visible;
423 }
424
425 bool sym_set_tristate_value(struct symbol *sym, tristate val)
426 {
427         tristate oldval = sym_get_tristate_value(sym);
428
429         if (oldval != val && !sym_tristate_within_range(sym, val))
430                 return false;
431
432         if (!(sym->flags & SYMBOL_DEF_USER)) {
433                 sym->flags |= SYMBOL_DEF_USER;
434                 sym_set_changed(sym);
435         }
436         /*
437          * setting a choice value also resets the new flag of the choice
438          * symbol and all other choice values.
439          */
440         if (sym_is_choice_value(sym) && val == yes) {
441                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
442                 struct property *prop;
443                 struct expr *e;
444
445                 cs->def[S_DEF_USER].val = sym;
446                 cs->flags |= SYMBOL_DEF_USER;
447                 prop = sym_get_choice_prop(cs);
448                 for (e = prop->expr; e; e = e->left.expr) {
449                         if (e->right.sym->visible != no)
450                                 e->right.sym->flags |= SYMBOL_DEF_USER;
451                 }
452         }
453
454         sym->def[S_DEF_USER].tri = val;
455         if (oldval != val)
456                 sym_clear_all_valid();
457
458         return true;
459 }
460
461 tristate sym_toggle_tristate_value(struct symbol *sym)
462 {
463         tristate oldval, newval;
464
465         oldval = newval = sym_get_tristate_value(sym);
466         do {
467                 switch (newval) {
468                 case no:
469                         newval = mod;
470                         break;
471                 case mod:
472                         newval = yes;
473                         break;
474                 case yes:
475                         newval = no;
476                         break;
477                 }
478                 if (sym_set_tristate_value(sym, newval))
479                         break;
480         } while (oldval != newval);
481         return newval;
482 }
483
484 bool sym_string_valid(struct symbol *sym, const char *str)
485 {
486         signed char ch;
487
488         switch (sym->type) {
489         case S_STRING:
490                 return true;
491         case S_INT:
492                 ch = *str++;
493                 if (ch == '-')
494                         ch = *str++;
495                 if (!isdigit(ch))
496                         return false;
497                 if (ch == '0' && *str != 0)
498                         return false;
499                 while ((ch = *str++)) {
500                         if (!isdigit(ch))
501                                 return false;
502                 }
503                 return true;
504         case S_HEX:
505                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
506                         str += 2;
507                 ch = *str++;
508                 do {
509                         if (!isxdigit(ch))
510                                 return false;
511                 } while ((ch = *str++));
512                 return true;
513         case S_BOOLEAN:
514         case S_TRISTATE:
515                 switch (str[0]) {
516                 case 'y': case 'Y':
517                 case 'm': case 'M':
518                 case 'n': case 'N':
519                         return true;
520                 }
521                 return false;
522         default:
523                 return false;
524         }
525 }
526
527 bool sym_string_within_range(struct symbol *sym, const char *str)
528 {
529         struct property *prop;
530         int val;
531
532         switch (sym->type) {
533         case S_STRING:
534                 return sym_string_valid(sym, str);
535         case S_INT:
536                 if (!sym_string_valid(sym, str))
537                         return false;
538                 prop = sym_get_range_prop(sym);
539                 if (!prop)
540                         return true;
541                 val = strtol(str, NULL, 10);
542                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
543                        val <= sym_get_range_val(prop->expr->right.sym, 10);
544         case S_HEX:
545                 if (!sym_string_valid(sym, str))
546                         return false;
547                 prop = sym_get_range_prop(sym);
548                 if (!prop)
549                         return true;
550                 val = strtol(str, NULL, 16);
551                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
552                        val <= sym_get_range_val(prop->expr->right.sym, 16);
553         case S_BOOLEAN:
554         case S_TRISTATE:
555                 switch (str[0]) {
556                 case 'y': case 'Y':
557                         return sym_tristate_within_range(sym, yes);
558                 case 'm': case 'M':
559                         return sym_tristate_within_range(sym, mod);
560                 case 'n': case 'N':
561                         return sym_tristate_within_range(sym, no);
562                 }
563                 return false;
564         default:
565                 return false;
566         }
567 }
568
569 bool sym_set_string_value(struct symbol *sym, const char *newval)
570 {
571         const char *oldval;
572         char *val;
573         int size;
574
575         switch (sym->type) {
576         case S_BOOLEAN:
577         case S_TRISTATE:
578                 switch (newval[0]) {
579                 case 'y': case 'Y':
580                         return sym_set_tristate_value(sym, yes);
581                 case 'm': case 'M':
582                         return sym_set_tristate_value(sym, mod);
583                 case 'n': case 'N':
584                         return sym_set_tristate_value(sym, no);
585                 }
586                 return false;
587         default:
588                 ;
589         }
590
591         if (!sym_string_within_range(sym, newval))
592                 return false;
593
594         if (!(sym->flags & SYMBOL_DEF_USER)) {
595                 sym->flags |= SYMBOL_DEF_USER;
596                 sym_set_changed(sym);
597         }
598
599         oldval = sym->def[S_DEF_USER].val;
600         size = strlen(newval) + 1;
601         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
602                 size += 2;
603                 sym->def[S_DEF_USER].val = val = malloc(size);
604                 *val++ = '0';
605                 *val++ = 'x';
606         } else if (!oldval || strcmp(oldval, newval))
607                 sym->def[S_DEF_USER].val = val = malloc(size);
608         else
609                 return true;
610
611         strcpy(val, newval);
612         free((void *)oldval);
613         sym_clear_all_valid();
614
615         return true;
616 }
617
618 const char *sym_get_string_value(struct symbol *sym)
619 {
620         tristate val;
621
622         switch (sym->type) {
623         case S_BOOLEAN:
624         case S_TRISTATE:
625                 val = sym_get_tristate_value(sym);
626                 switch (val) {
627                 case no:
628                         return "n";
629                 case mod:
630                         return "m";
631                 case yes:
632                         return "y";
633                 }
634                 break;
635         default:
636                 ;
637         }
638         return (const char *)sym->curr.val;
639 }
640
641 bool sym_is_changable(struct symbol *sym)
642 {
643         return sym->visible > sym->rev_dep.tri;
644 }
645
646 struct symbol *sym_lookup(const char *name, int isconst)
647 {
648         struct symbol *symbol;
649         const char *ptr;
650         char *new_name;
651         int hash = 0;
652
653         if (name) {
654                 if (name[0] && !name[1]) {
655                         switch (name[0]) {
656                         case 'y': return &symbol_yes;
657                         case 'm': return &symbol_mod;
658                         case 'n': return &symbol_no;
659                         }
660                 }
661                 for (ptr = name; *ptr; ptr++)
662                         hash += *ptr;
663                 hash &= 0xff;
664
665                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
666                         if (!strcmp(symbol->name, name)) {
667                                 if ((isconst && symbol->flags & SYMBOL_CONST) ||
668                                     (!isconst && !(symbol->flags & SYMBOL_CONST)))
669                                         return symbol;
670                         }
671                 }
672                 new_name = strdup(name);
673         } else {
674                 new_name = NULL;
675                 hash = 256;
676         }
677
678         symbol = malloc(sizeof(*symbol));
679         memset(symbol, 0, sizeof(*symbol));
680         symbol->name = new_name;
681         symbol->type = S_UNKNOWN;
682         if (isconst)
683                 symbol->flags |= SYMBOL_CONST;
684
685         symbol->next = symbol_hash[hash];
686         symbol_hash[hash] = symbol;
687
688         return symbol;
689 }
690
691 struct symbol *sym_find(const char *name)
692 {
693         struct symbol *symbol = NULL;
694         const char *ptr;
695         int hash = 0;
696
697         if (!name)
698                 return NULL;
699
700         if (name[0] && !name[1]) {
701                 switch (name[0]) {
702                 case 'y': return &symbol_yes;
703                 case 'm': return &symbol_mod;
704                 case 'n': return &symbol_no;
705                 }
706         }
707         for (ptr = name; *ptr; ptr++)
708                 hash += *ptr;
709         hash &= 0xff;
710
711         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
712                 if (!strcmp(symbol->name, name) &&
713                     !(symbol->flags & SYMBOL_CONST))
714                                 break;
715         }
716
717         return symbol;
718 }
719
720 struct symbol **sym_re_search(const char *pattern)
721 {
722         struct symbol *sym, **sym_arr = NULL;
723         int i, cnt, size;
724         regex_t re;
725
726         cnt = size = 0;
727         /* Skip if empty */
728         if (strlen(pattern) == 0)
729                 return NULL;
730         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
731                 return NULL;
732
733         for_all_symbols(i, sym) {
734                 if (sym->flags & SYMBOL_CONST || !sym->name)
735                         continue;
736                 if (regexec(&re, sym->name, 0, NULL, 0))
737                         continue;
738                 if (cnt + 1 >= size) {
739                         void *tmp = sym_arr;
740                         size += 16;
741                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
742                         if (!sym_arr) {
743                                 free(tmp);
744                                 return NULL;
745                         }
746                 }
747                 sym_arr[cnt++] = sym;
748         }
749         if (sym_arr)
750                 sym_arr[cnt] = NULL;
751         regfree(&re);
752
753         return sym_arr;
754 }
755
756
757 struct symbol *sym_check_deps(struct symbol *sym);
758
759 static struct symbol *sym_check_expr_deps(struct expr *e)
760 {
761         struct symbol *sym;
762
763         if (!e)
764                 return NULL;
765         switch (e->type) {
766         case E_OR:
767         case E_AND:
768                 sym = sym_check_expr_deps(e->left.expr);
769                 if (sym)
770                         return sym;
771                 return sym_check_expr_deps(e->right.expr);
772         case E_NOT:
773                 return sym_check_expr_deps(e->left.expr);
774         case E_EQUAL:
775         case E_UNEQUAL:
776                 sym = sym_check_deps(e->left.sym);
777                 if (sym)
778                         return sym;
779                 return sym_check_deps(e->right.sym);
780         case E_SYMBOL:
781                 return sym_check_deps(e->left.sym);
782         default:
783                 break;
784         }
785         printf("Oops! How to check %d?\n", e->type);
786         return NULL;
787 }
788
789 /* return NULL when dependencies are OK */
790 struct symbol *sym_check_deps(struct symbol *sym)
791 {
792         struct symbol *sym2;
793         struct property *prop;
794
795         if (sym->flags & SYMBOL_CHECK) {
796                 fprintf(stderr, "%s:%d:error: found recursive dependency: %s",
797                         sym->prop->file->name, sym->prop->lineno, sym->name);
798                 return sym;
799         }
800         if (sym->flags & SYMBOL_CHECKED)
801                 return NULL;
802
803         sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
804         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
805         if (sym2)
806                 goto out;
807
808         for (prop = sym->prop; prop; prop = prop->next) {
809                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
810                         continue;
811                 sym2 = sym_check_expr_deps(prop->visible.expr);
812                 if (sym2)
813                         goto out;
814                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
815                         continue;
816                 sym2 = sym_check_expr_deps(prop->expr);
817                 if (sym2)
818                         goto out;
819         }
820 out:
821         if (sym2)
822                 fprintf(stderr, " -> %s%s", sym->name, sym2 == sym? "\n": "");
823         sym->flags &= ~SYMBOL_CHECK;
824         return sym2;
825 }
826
827 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
828 {
829         struct property *prop;
830         struct property **propp;
831
832         prop = malloc(sizeof(*prop));
833         memset(prop, 0, sizeof(*prop));
834         prop->type = type;
835         prop->sym = sym;
836         prop->file = current_file;
837         prop->lineno = zconf_lineno();
838
839         /* append property to the prop list of symbol */
840         if (sym) {
841                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
842                         ;
843                 *propp = prop;
844         }
845
846         return prop;
847 }
848
849 struct symbol *prop_get_symbol(struct property *prop)
850 {
851         if (prop->expr && (prop->expr->type == E_SYMBOL ||
852                            prop->expr->type == E_LIST))
853                 return prop->expr->left.sym;
854         return NULL;
855 }
856
857 const char *prop_get_type_name(enum prop_type type)
858 {
859         switch (type) {
860         case P_PROMPT:
861                 return "prompt";
862         case P_ENV:
863                 return "env";
864         case P_COMMENT:
865                 return "comment";
866         case P_MENU:
867                 return "menu";
868         case P_DEFAULT:
869                 return "default";
870         case P_CHOICE:
871                 return "choice";
872         case P_SELECT:
873                 return "select";
874         case P_RANGE:
875                 return "range";
876         case P_UNKNOWN:
877                 break;
878         }
879         return "unknown";
880 }
881
882 void prop_add_env(const char *env)
883 {
884         struct symbol *sym, *sym2;
885         struct property *prop;
886         char *p;
887
888         sym = current_entry->sym;
889         sym->flags |= SYMBOL_AUTO;
890         for_all_properties(sym, prop, P_ENV) {
891                 sym2 = prop_get_symbol(prop);
892                 if (strcmp(sym2->name, env))
893                         menu_warn(current_entry, "redefining environment symbol from %s",
894                                   sym2->name);
895                 return;
896         }
897
898         prop = prop_alloc(P_ENV, sym);
899         prop->expr = expr_alloc_symbol(sym_lookup(env, 1));
900
901         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
902         sym_env_list->right.sym = sym;
903
904         p = getenv(env);
905         if (p)
906                 sym_add_default(sym, p);
907         else
908                 menu_warn(current_entry, "environment variable %s undefined", env);
909 }