BNX2X: spatch ktime_ functions
[akaros.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         int flags;
266
267         /* first calculate all choice values' visibilities */
268         flags = sym->flags;
269         prop = sym_get_choice_prop(sym);
270         expr_list_for_each_sym(prop->expr, e, def_sym) {
271                 sym_calc_visibility(def_sym);
272                 if (def_sym->visible != no)
273                         flags &= def_sym->flags;
274         }
275
276         sym->flags &= flags | ~SYMBOL_DEF_USER;
277
278         /* is the user choice visible? */
279         def_sym = sym->def[S_DEF_USER].val;
280         if (def_sym && def_sym->visible != no)
281                 return def_sym;
282
283         def_sym = sym_choice_default(sym);
284
285         if (def_sym == NULL)
286                 /* no choice? reset tristate value */
287                 sym->curr.tri = no;
288
289         return def_sym;
290 }
291
292 void sym_calc_value(struct symbol *sym)
293 {
294         struct symbol_value newval, oldval;
295         struct property *prop;
296         struct expr *e;
297
298         if (!sym)
299                 return;
300
301         if (sym->flags & SYMBOL_VALID)
302                 return;
303         sym->flags |= SYMBOL_VALID;
304
305         oldval = sym->curr;
306
307         switch (sym->type) {
308         case S_INT:
309         case S_HEX:
310         case S_STRING:
311                 newval = symbol_empty.curr;
312                 break;
313         case S_BOOLEAN:
314         case S_TRISTATE:
315                 newval = symbol_no.curr;
316                 break;
317         default:
318                 sym->curr.val = sym->name;
319                 sym->curr.tri = no;
320                 return;
321         }
322         if (!sym_is_choice_value(sym))
323                 sym->flags &= ~SYMBOL_WRITE;
324
325         sym_calc_visibility(sym);
326
327         /* set default if recursively called */
328         sym->curr = newval;
329
330         switch (sym_get_type(sym)) {
331         case S_BOOLEAN:
332         case S_TRISTATE:
333                 if (sym_is_choice_value(sym) && sym->visible == yes) {
334                         prop = sym_get_choice_prop(sym);
335                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
336                 } else {
337                         if (sym->visible != no) {
338                                 /* if the symbol is visible use the user value
339                                  * if available, otherwise try the default value
340                                  */
341                                 sym->flags |= SYMBOL_WRITE;
342                                 if (sym_has_value(sym)) {
343                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
344                                                               sym->visible);
345                                         goto calc_newval;
346                                 }
347                         }
348                         if (sym->rev_dep.tri != no)
349                                 sym->flags |= SYMBOL_WRITE;
350                         if (!sym_is_choice(sym)) {
351                                 prop = sym_get_default_prop(sym);
352                                 if (prop) {
353                                         sym->flags |= SYMBOL_WRITE;
354                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
355                                                               prop->visible.tri);
356                                 }
357                         }
358                 calc_newval:
359                         if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
360                                 struct expr *e;
361                                 e = expr_simplify_unmet_dep(sym->rev_dep.expr,
362                                     sym->dir_dep.expr);
363                                 fprintf(stderr, "warning: (");
364                                 expr_fprint(e, stderr);
365                                 fprintf(stderr, ") selects %s which has unmet direct dependencies (",
366                                         sym->name);
367                                 expr_fprint(sym->dir_dep.expr, stderr);
368                                 fprintf(stderr, ")\n");
369                                 expr_free(e);
370                         }
371                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
372                 }
373                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
374                         newval.tri = yes;
375                 break;
376         case S_STRING:
377         case S_HEX:
378         case S_INT:
379                 if (sym->visible != no) {
380                         sym->flags |= SYMBOL_WRITE;
381                         if (sym_has_value(sym)) {
382                                 newval.val = sym->def[S_DEF_USER].val;
383                                 break;
384                         }
385                 }
386                 prop = sym_get_default_prop(sym);
387                 if (prop) {
388                         struct symbol *ds = prop_get_symbol(prop);
389                         if (ds) {
390                                 sym->flags |= SYMBOL_WRITE;
391                                 sym_calc_value(ds);
392                                 newval.val = ds->curr.val;
393                         }
394                 }
395                 break;
396         default:
397                 ;
398         }
399
400         sym->curr = newval;
401         if (sym_is_choice(sym) && newval.tri == yes)
402                 sym->curr.val = sym_calc_choice(sym);
403         sym_validate_range(sym);
404
405         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
406                 sym_set_changed(sym);
407                 if (modules_sym == sym) {
408                         sym_set_all_changed();
409                         modules_val = modules_sym->curr.tri;
410                 }
411         }
412
413         if (sym_is_choice(sym)) {
414                 struct symbol *choice_sym;
415
416                 prop = sym_get_choice_prop(sym);
417                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
418                         if ((sym->flags & SYMBOL_WRITE) &&
419                             choice_sym->visible != no)
420                                 choice_sym->flags |= SYMBOL_WRITE;
421                         if (sym->flags & SYMBOL_CHANGED)
422                                 sym_set_changed(choice_sym);
423                 }
424         }
425
426         if (sym->flags & SYMBOL_AUTO)
427                 sym->flags &= ~SYMBOL_WRITE;
428 }
429
430 void sym_clear_all_valid(void)
431 {
432         struct symbol *sym;
433         int i;
434
435         for_all_symbols(i, sym)
436                 sym->flags &= ~SYMBOL_VALID;
437         sym_add_change_count(1);
438         if (modules_sym)
439                 sym_calc_value(modules_sym);
440 }
441
442 void sym_set_changed(struct symbol *sym)
443 {
444         struct property *prop;
445
446         sym->flags |= SYMBOL_CHANGED;
447         for (prop = sym->prop; prop; prop = prop->next) {
448                 if (prop->menu)
449                         prop->menu->flags |= MENU_CHANGED;
450         }
451 }
452
453 void sym_set_all_changed(void)
454 {
455         struct symbol *sym;
456         int i;
457
458         for_all_symbols(i, sym)
459                 sym_set_changed(sym);
460 }
461
462 bool sym_tristate_within_range(struct symbol *sym, tristate val)
463 {
464         int type = sym_get_type(sym);
465
466         if (sym->visible == no)
467                 return false;
468
469         if (type != S_BOOLEAN && type != S_TRISTATE)
470                 return false;
471
472         if (type == S_BOOLEAN && val == mod)
473                 return false;
474         if (sym->visible <= sym->rev_dep.tri)
475                 return false;
476         if (sym_is_choice_value(sym) && sym->visible == yes)
477                 return val == yes;
478         return val >= sym->rev_dep.tri && val <= sym->visible;
479 }
480
481 bool sym_set_tristate_value(struct symbol *sym, tristate val)
482 {
483         tristate oldval = sym_get_tristate_value(sym);
484
485         if (oldval != val && !sym_tristate_within_range(sym, val))
486                 return false;
487
488         if (!(sym->flags & SYMBOL_DEF_USER)) {
489                 sym->flags |= SYMBOL_DEF_USER;
490                 sym_set_changed(sym);
491         }
492         /*
493          * setting a choice value also resets the new flag of the choice
494          * symbol and all other choice values.
495          */
496         if (sym_is_choice_value(sym) && val == yes) {
497                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
498                 struct property *prop;
499                 struct expr *e;
500
501                 cs->def[S_DEF_USER].val = sym;
502                 cs->flags |= SYMBOL_DEF_USER;
503                 prop = sym_get_choice_prop(cs);
504                 for (e = prop->expr; e; e = e->left.expr) {
505                         if (e->right.sym->visible != no)
506                                 e->right.sym->flags |= SYMBOL_DEF_USER;
507                 }
508         }
509
510         sym->def[S_DEF_USER].tri = val;
511         if (oldval != val)
512                 sym_clear_all_valid();
513
514         return true;
515 }
516
517 tristate sym_toggle_tristate_value(struct symbol *sym)
518 {
519         tristate oldval, newval;
520
521         oldval = newval = sym_get_tristate_value(sym);
522         do {
523                 switch (newval) {
524                 case no:
525                         newval = mod;
526                         break;
527                 case mod:
528                         newval = yes;
529                         break;
530                 case yes:
531                         newval = no;
532                         break;
533                 }
534                 if (sym_set_tristate_value(sym, newval))
535                         break;
536         } while (oldval != newval);
537         return newval;
538 }
539
540 bool sym_string_valid(struct symbol *sym, const char *str)
541 {
542         signed char ch;
543
544         switch (sym->type) {
545         case S_STRING:
546                 return true;
547         case S_INT:
548                 ch = *str++;
549                 if (ch == '-')
550                         ch = *str++;
551                 if (!isdigit(ch))
552                         return false;
553                 if (ch == '0' && *str != 0)
554                         return false;
555                 while ((ch = *str++)) {
556                         if (!isdigit(ch))
557                                 return false;
558                 }
559                 return true;
560         case S_HEX:
561                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
562                         str += 2;
563                 ch = *str++;
564                 do {
565                         if (!isxdigit(ch))
566                                 return false;
567                 } while ((ch = *str++));
568                 return true;
569         case S_BOOLEAN:
570         case S_TRISTATE:
571                 switch (str[0]) {
572                 case 'y': case 'Y':
573                 case 'm': case 'M':
574                 case 'n': case 'N':
575                         return true;
576                 }
577                 return false;
578         default:
579                 return false;
580         }
581 }
582
583 bool sym_string_within_range(struct symbol *sym, const char *str)
584 {
585         struct property *prop;
586         int val;
587
588         switch (sym->type) {
589         case S_STRING:
590                 return sym_string_valid(sym, str);
591         case S_INT:
592                 if (!sym_string_valid(sym, str))
593                         return false;
594                 prop = sym_get_range_prop(sym);
595                 if (!prop)
596                         return true;
597                 val = strtol(str, NULL, 10);
598                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
599                        val <= sym_get_range_val(prop->expr->right.sym, 10);
600         case S_HEX:
601                 if (!sym_string_valid(sym, str))
602                         return false;
603                 prop = sym_get_range_prop(sym);
604                 if (!prop)
605                         return true;
606                 val = strtol(str, NULL, 16);
607                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
608                        val <= sym_get_range_val(prop->expr->right.sym, 16);
609         case S_BOOLEAN:
610         case S_TRISTATE:
611                 switch (str[0]) {
612                 case 'y': case 'Y':
613                         return sym_tristate_within_range(sym, yes);
614                 case 'm': case 'M':
615                         return sym_tristate_within_range(sym, mod);
616                 case 'n': case 'N':
617                         return sym_tristate_within_range(sym, no);
618                 }
619                 return false;
620         default:
621                 return false;
622         }
623 }
624
625 bool sym_set_string_value(struct symbol *sym, const char *newval)
626 {
627         const char *oldval;
628         char *val;
629         int size;
630
631         switch (sym->type) {
632         case S_BOOLEAN:
633         case S_TRISTATE:
634                 switch (newval[0]) {
635                 case 'y': case 'Y':
636                         return sym_set_tristate_value(sym, yes);
637                 case 'm': case 'M':
638                         return sym_set_tristate_value(sym, mod);
639                 case 'n': case 'N':
640                         return sym_set_tristate_value(sym, no);
641                 }
642                 return false;
643         default:
644                 ;
645         }
646
647         if (!sym_string_within_range(sym, newval))
648                 return false;
649
650         if (!(sym->flags & SYMBOL_DEF_USER)) {
651                 sym->flags |= SYMBOL_DEF_USER;
652                 sym_set_changed(sym);
653         }
654
655         oldval = sym->def[S_DEF_USER].val;
656         size = strlen(newval) + 1;
657         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
658                 size += 2;
659                 sym->def[S_DEF_USER].val = val = malloc(size);
660                 *val++ = '0';
661                 *val++ = 'x';
662         } else if (!oldval || strcmp(oldval, newval))
663                 sym->def[S_DEF_USER].val = val = malloc(size);
664         else
665                 return true;
666
667         strcpy(val, newval);
668         free((void *)oldval);
669         sym_clear_all_valid();
670
671         return true;
672 }
673
674 /*
675  * Find the default value associated to a symbol.
676  * For tristate symbol handle the modules=n case
677  * in which case "m" becomes "y".
678  * If the symbol does not have any default then fallback
679  * to the fixed default values.
680  */
681 const char *sym_get_string_default(struct symbol *sym)
682 {
683         struct property *prop;
684         struct symbol *ds;
685         const char *str;
686         tristate val;
687
688         sym_calc_visibility(sym);
689         sym_calc_value(modules_sym);
690         val = symbol_no.curr.tri;
691         str = symbol_empty.curr.val;
692
693         /* If symbol has a default value look it up */
694         prop = sym_get_default_prop(sym);
695         if (prop != NULL) {
696                 switch (sym->type) {
697                 case S_BOOLEAN:
698                 case S_TRISTATE:
699                         /* The visibility may limit the value from yes => mod */
700                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
701                         break;
702                 default:
703                         /*
704                          * The following fails to handle the situation
705                          * where a default value is further limited by
706                          * the valid range.
707                          */
708                         ds = prop_get_symbol(prop);
709                         if (ds != NULL) {
710                                 sym_calc_value(ds);
711                                 str = (const char *)ds->curr.val;
712                         }
713                 }
714         }
715
716         /* Handle select statements */
717         val = EXPR_OR(val, sym->rev_dep.tri);
718
719         /* transpose mod to yes if modules are not enabled */
720         if (val == mod)
721                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
722                         val = yes;
723
724         /* transpose mod to yes if type is bool */
725         if (sym->type == S_BOOLEAN && val == mod)
726                 val = yes;
727
728         switch (sym->type) {
729         case S_BOOLEAN:
730         case S_TRISTATE:
731                 switch (val) {
732                 case no: return "n";
733                 case mod: return "m";
734                 case yes: return "y";
735                 }
736         case S_INT:
737         case S_HEX:
738                 return str;
739         case S_STRING:
740                 return str;
741         case S_OTHER:
742         case S_UNKNOWN:
743                 break;
744         }
745         return "";
746 }
747
748 const char *sym_get_string_value(struct symbol *sym)
749 {
750         tristate val;
751
752         switch (sym->type) {
753         case S_BOOLEAN:
754         case S_TRISTATE:
755                 val = sym_get_tristate_value(sym);
756                 switch (val) {
757                 case no:
758                         return "n";
759                 case mod:
760                         sym_calc_value(modules_sym);
761                         return (modules_sym->curr.tri == no) ? "n" : "m";
762                 case yes:
763                         return "y";
764                 }
765                 break;
766         default:
767                 ;
768         }
769         return (const char *)sym->curr.val;
770 }
771
772 bool sym_is_changable(struct symbol *sym)
773 {
774         return sym->visible > sym->rev_dep.tri;
775 }
776
777 static unsigned strhash(const char *s)
778 {
779         /* fnv32 hash */
780         unsigned hash = 2166136261U;
781         for (; *s; s++)
782                 hash = (hash ^ *s) * 0x01000193;
783         return hash;
784 }
785
786 struct symbol *sym_lookup(const char *name, int flags)
787 {
788         struct symbol *symbol;
789         char *new_name;
790         int hash;
791
792         if (name) {
793                 if (name[0] && !name[1]) {
794                         switch (name[0]) {
795                         case 'y': return &symbol_yes;
796                         case 'm': return &symbol_mod;
797                         case 'n': return &symbol_no;
798                         }
799                 }
800                 hash = strhash(name) % SYMBOL_HASHSIZE;
801
802                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
803                         if (symbol->name &&
804                             !strcmp(symbol->name, name) &&
805                             (flags ? symbol->flags & flags
806                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
807                                 return symbol;
808                 }
809                 new_name = strdup(name);
810         } else {
811                 new_name = NULL;
812                 hash = 0;
813         }
814
815         symbol = malloc(sizeof(*symbol));
816         memset(symbol, 0, sizeof(*symbol));
817         symbol->name = new_name;
818         symbol->type = S_UNKNOWN;
819         symbol->flags |= flags;
820
821         symbol->next = symbol_hash[hash];
822         symbol_hash[hash] = symbol;
823
824         return symbol;
825 }
826
827 struct symbol *sym_find(const char *name)
828 {
829         struct symbol *symbol = NULL;
830         int hash = 0;
831
832         if (!name)
833                 return NULL;
834
835         if (name[0] && !name[1]) {
836                 switch (name[0]) {
837                 case 'y': return &symbol_yes;
838                 case 'm': return &symbol_mod;
839                 case 'n': return &symbol_no;
840                 }
841         }
842         hash = strhash(name) % SYMBOL_HASHSIZE;
843
844         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
845                 if (symbol->name &&
846                     !strcmp(symbol->name, name) &&
847                     !(symbol->flags & SYMBOL_CONST))
848                                 break;
849         }
850
851         return symbol;
852 }
853
854 /*
855  * Expand symbol's names embedded in the string given in argument. Symbols'
856  * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
857  * the empty string.
858  */
859 const char *sym_expand_string_value(const char *in)
860 {
861         const char *src;
862         char *res;
863         size_t reslen;
864
865         reslen = strlen(in) + 1;
866         res = malloc(reslen);
867         res[0] = '\0';
868
869         while ((src = strchr(in, '$'))) {
870                 char *p, name[SYMBOL_MAXLENGTH];
871                 const char *symval = "";
872                 struct symbol *sym;
873                 size_t newlen;
874
875                 strncat(res, in, src - in);
876                 src++;
877
878                 p = name;
879                 while (isalnum(*src) || *src == '_')
880                         *p++ = *src++;
881                 *p = '\0';
882
883                 sym = sym_find(name);
884                 if (sym != NULL) {
885                         sym_calc_value(sym);
886                         symval = sym_get_string_value(sym);
887                 }
888
889                 newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
890                 if (newlen > reslen) {
891                         reslen = newlen;
892                         res = realloc(res, reslen);
893                 }
894
895                 strcat(res, symval);
896                 in = src;
897         }
898         strcat(res, in);
899
900         return res;
901 }
902
903 const char *sym_escape_string_value(const char *in)
904 {
905         const char *p;
906         size_t reslen;
907         char *res;
908         size_t l;
909
910         reslen = strlen(in) + strlen("\"\"") + 1;
911
912         p = in;
913         for (;;) {
914                 l = strcspn(p, "\"\\");
915                 p += l;
916
917                 if (p[0] == '\0')
918                         break;
919
920                 reslen++;
921                 p++;
922         }
923
924         res = malloc(reslen);
925         res[0] = '\0';
926
927         strcat(res, "\"");
928
929         p = in;
930         for (;;) {
931                 l = strcspn(p, "\"\\");
932                 strncat(res, p, l);
933                 p += l;
934
935                 if (p[0] == '\0')
936                         break;
937
938                 strcat(res, "\\");
939                 strncat(res, p++, 1);
940         }
941
942         strcat(res, "\"");
943         return res;
944 }
945
946 struct symbol **sym_re_search(const char *pattern)
947 {
948         struct symbol *sym, **sym_arr = NULL;
949         int i, cnt, size;
950         regex_t re;
951
952         cnt = size = 0;
953         /* Skip if empty */
954         if (strlen(pattern) == 0)
955                 return NULL;
956         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
957                 return NULL;
958
959         for_all_symbols(i, sym) {
960                 if (sym->flags & SYMBOL_CONST || !sym->name)
961                         continue;
962                 if (regexec(&re, sym->name, 0, NULL, 0))
963                         continue;
964                 if (cnt + 1 >= size) {
965                         void *tmp = sym_arr;
966                         size += 16;
967                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
968                         if (!sym_arr) {
969                                 free(tmp);
970                                 return NULL;
971                         }
972                 }
973                 sym_calc_value(sym);
974                 sym_arr[cnt++] = sym;
975         }
976         if (sym_arr)
977                 sym_arr[cnt] = NULL;
978         regfree(&re);
979
980         return sym_arr;
981 }
982
983 /*
984  * When we check for recursive dependencies we use a stack to save
985  * current state so we can print out relevant info to user.
986  * The entries are located on the call stack so no need to free memory.
987  * Note inser() remove() must always match to properly clear the stack.
988  */
989 static struct dep_stack {
990         struct dep_stack *prev, *next;
991         struct symbol *sym;
992         struct property *prop;
993         struct expr *expr;
994 } *check_top;
995
996 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
997 {
998         memset(stack, 0, sizeof(*stack));
999         if (check_top)
1000                 check_top->next = stack;
1001         stack->prev = check_top;
1002         stack->sym = sym;
1003         check_top = stack;
1004 }
1005
1006 static void dep_stack_remove(void)
1007 {
1008         check_top = check_top->prev;
1009         if (check_top)
1010                 check_top->next = NULL;
1011 }
1012
1013 /*
1014  * Called when we have detected a recursive dependency.
1015  * check_top point to the top of the stact so we use
1016  * the ->prev pointer to locate the bottom of the stack.
1017  */
1018 static void sym_check_print_recursive(struct symbol *last_sym)
1019 {
1020         struct dep_stack *stack;
1021         struct symbol *sym, *next_sym;
1022         struct menu *menu = NULL;
1023         struct property *prop;
1024         struct dep_stack cv_stack;
1025
1026         if (sym_is_choice_value(last_sym)) {
1027                 dep_stack_insert(&cv_stack, last_sym);
1028                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1029         }
1030
1031         for (stack = check_top; stack != NULL; stack = stack->prev)
1032                 if (stack->sym == last_sym)
1033                         break;
1034         if (!stack) {
1035                 fprintf(stderr, "unexpected recursive dependency error\n");
1036                 return;
1037         }
1038
1039         for (; stack; stack = stack->next) {
1040                 sym = stack->sym;
1041                 next_sym = stack->next ? stack->next->sym : last_sym;
1042                 prop = stack->prop;
1043                 if (prop == NULL)
1044                         prop = stack->sym->prop;
1045
1046                 /* for choice values find the menu entry (used below) */
1047                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1048                         for (prop = sym->prop; prop; prop = prop->next) {
1049                                 menu = prop->menu;
1050                                 if (prop->menu)
1051                                         break;
1052                         }
1053                 }
1054                 if (stack->sym == last_sym)
1055                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1056                                 prop->file->name, prop->lineno);
1057                 if (stack->expr) {
1058                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1059                                 prop->file->name, prop->lineno,
1060                                 sym->name ? sym->name : "<choice>",
1061                                 prop_get_type_name(prop->type),
1062                                 next_sym->name ? next_sym->name : "<choice>");
1063                 } else if (stack->prop) {
1064                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1065                                 prop->file->name, prop->lineno,
1066                                 sym->name ? sym->name : "<choice>",
1067                                 next_sym->name ? next_sym->name : "<choice>");
1068                 } else if (sym_is_choice(sym)) {
1069                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1070                                 menu->file->name, menu->lineno,
1071                                 sym->name ? sym->name : "<choice>",
1072                                 next_sym->name ? next_sym->name : "<choice>");
1073                 } else if (sym_is_choice_value(sym)) {
1074                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1075                                 menu->file->name, menu->lineno,
1076                                 sym->name ? sym->name : "<choice>",
1077                                 next_sym->name ? next_sym->name : "<choice>");
1078                 } else {
1079                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1080                                 prop->file->name, prop->lineno,
1081                                 sym->name ? sym->name : "<choice>",
1082                                 next_sym->name ? next_sym->name : "<choice>");
1083                 }
1084         }
1085
1086         if (check_top == &cv_stack)
1087                 dep_stack_remove();
1088 }
1089
1090 static struct symbol *sym_check_expr_deps(struct expr *e)
1091 {
1092         struct symbol *sym;
1093
1094         if (!e)
1095                 return NULL;
1096         switch (e->type) {
1097         case E_OR:
1098         case E_AND:
1099                 sym = sym_check_expr_deps(e->left.expr);
1100                 if (sym)
1101                         return sym;
1102                 return sym_check_expr_deps(e->right.expr);
1103         case E_NOT:
1104                 return sym_check_expr_deps(e->left.expr);
1105         case E_EQUAL:
1106         case E_UNEQUAL:
1107                 sym = sym_check_deps(e->left.sym);
1108                 if (sym)
1109                         return sym;
1110                 return sym_check_deps(e->right.sym);
1111         case E_SYMBOL:
1112                 return sym_check_deps(e->left.sym);
1113         default:
1114                 break;
1115         }
1116         printf("Oops! How to check %d?\n", e->type);
1117         return NULL;
1118 }
1119
1120 /* return NULL when dependencies are OK */
1121 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1122 {
1123         struct symbol *sym2;
1124         struct property *prop;
1125         struct dep_stack stack;
1126
1127         dep_stack_insert(&stack, sym);
1128
1129         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1130         if (sym2)
1131                 goto out;
1132
1133         for (prop = sym->prop; prop; prop = prop->next) {
1134                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1135                         continue;
1136                 stack.prop = prop;
1137                 sym2 = sym_check_expr_deps(prop->visible.expr);
1138                 if (sym2)
1139                         break;
1140                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1141                         continue;
1142                 stack.expr = prop->expr;
1143                 sym2 = sym_check_expr_deps(prop->expr);
1144                 if (sym2)
1145                         break;
1146                 stack.expr = NULL;
1147         }
1148
1149 out:
1150         dep_stack_remove();
1151
1152         return sym2;
1153 }
1154
1155 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1156 {
1157         struct symbol *sym, *sym2;
1158         struct property *prop;
1159         struct expr *e;
1160         struct dep_stack stack;
1161
1162         dep_stack_insert(&stack, choice);
1163
1164         prop = sym_get_choice_prop(choice);
1165         expr_list_for_each_sym(prop->expr, e, sym)
1166                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1167
1168         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1169         sym2 = sym_check_sym_deps(choice);
1170         choice->flags &= ~SYMBOL_CHECK;
1171         if (sym2)
1172                 goto out;
1173
1174         expr_list_for_each_sym(prop->expr, e, sym) {
1175                 sym2 = sym_check_sym_deps(sym);
1176                 if (sym2)
1177                         break;
1178         }
1179 out:
1180         expr_list_for_each_sym(prop->expr, e, sym)
1181                 sym->flags &= ~SYMBOL_CHECK;
1182
1183         if (sym2 && sym_is_choice_value(sym2) &&
1184             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1185                 sym2 = choice;
1186
1187         dep_stack_remove();
1188
1189         return sym2;
1190 }
1191
1192 struct symbol *sym_check_deps(struct symbol *sym)
1193 {
1194         struct symbol *sym2;
1195         struct property *prop;
1196
1197         if (sym->flags & SYMBOL_CHECK) {
1198                 sym_check_print_recursive(sym);
1199                 return sym;
1200         }
1201         if (sym->flags & SYMBOL_CHECKED)
1202                 return NULL;
1203
1204         if (sym_is_choice_value(sym)) {
1205                 struct dep_stack stack;
1206
1207                 /* for choice groups start the check with main choice symbol */
1208                 dep_stack_insert(&stack, sym);
1209                 prop = sym_get_choice_prop(sym);
1210                 sym2 = sym_check_deps(prop_get_symbol(prop));
1211                 dep_stack_remove();
1212         } else if (sym_is_choice(sym)) {
1213                 sym2 = sym_check_choice_deps(sym);
1214         } else {
1215                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1216                 sym2 = sym_check_sym_deps(sym);
1217                 sym->flags &= ~SYMBOL_CHECK;
1218         }
1219
1220         if (sym2 && sym2 == sym)
1221                 sym2 = NULL;
1222
1223         return sym2;
1224 }
1225
1226 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1227 {
1228         struct property *prop;
1229         struct property **propp;
1230
1231         prop = malloc(sizeof(*prop));
1232         memset(prop, 0, sizeof(*prop));
1233         prop->type = type;
1234         prop->sym = sym;
1235         prop->file = current_file;
1236         prop->lineno = zconf_lineno();
1237
1238         /* append property to the prop list of symbol */
1239         if (sym) {
1240                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1241                         ;
1242                 *propp = prop;
1243         }
1244
1245         return prop;
1246 }
1247
1248 struct symbol *prop_get_symbol(struct property *prop)
1249 {
1250         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1251                            prop->expr->type == E_LIST))
1252                 return prop->expr->left.sym;
1253         return NULL;
1254 }
1255
1256 const char *prop_get_type_name(enum prop_type type)
1257 {
1258         switch (type) {
1259         case P_PROMPT:
1260                 return "prompt";
1261         case P_ENV:
1262                 return "env";
1263         case P_COMMENT:
1264                 return "comment";
1265         case P_MENU:
1266                 return "menu";
1267         case P_DEFAULT:
1268                 return "default";
1269         case P_CHOICE:
1270                 return "choice";
1271         case P_SELECT:
1272                 return "select";
1273         case P_RANGE:
1274                 return "range";
1275         case P_SYMBOL:
1276                 return "symbol";
1277         case P_UNKNOWN:
1278                 break;
1279         }
1280         return "unknown";
1281 }
1282
1283 static void prop_add_env(const char *env)
1284 {
1285         struct symbol *sym, *sym2;
1286         struct property *prop;
1287         char *p;
1288
1289         sym = current_entry->sym;
1290         sym->flags |= SYMBOL_AUTO;
1291         for_all_properties(sym, prop, P_ENV) {
1292                 sym2 = prop_get_symbol(prop);
1293                 if (strcmp(sym2->name, env))
1294                         menu_warn(current_entry, "redefining environment symbol from %s",
1295                                   sym2->name);
1296                 return;
1297         }
1298
1299         prop = prop_alloc(P_ENV, sym);
1300         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1301
1302         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1303         sym_env_list->right.sym = sym;
1304
1305         p = getenv(env);
1306         if (p)
1307                 sym_add_default(sym, p);
1308         else
1309                 menu_warn(current_entry, "environment variable %s undefined", env);
1310 }