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