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