release/src-rt-6.x.4708/linux/linux-2.6.36/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                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 354                 }
 355                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 356                         newval.tri = yes;
 357                 break;
 358         case S_STRING:
 359         case S_HEX:
 360         case S_INT:
 361                 if (sym->visible != no) {
 362                         sym->flags |= SYMBOL_WRITE;
 363                         if (sym_has_value(sym)) {
 364                                 newval.val = sym->def[S_DEF_USER].val;
 365                                 break;
 366                         }
 367                 }
 368                 prop = sym_get_default_prop(sym);
 369                 if (prop) {
 370                         struct symbol *ds = prop_get_symbol(prop);
 371                         if (ds) {
 372                                 sym->flags |= SYMBOL_WRITE;
 373                                 sym_calc_value(ds);
 374                                 newval.val = ds->curr.val;
 375                         }
 376                 }
 377                 break;
 378         default:
 379                 ;
 380         }
 381
 382         sym->curr = newval;
 383         if (sym_is_choice(sym) && newval.tri == yes)
 384                 sym->curr.val = sym_calc_choice(sym);
 385         sym_validate_range(sym);
 386
 387         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 388                 sym_set_changed(sym);
 389                 if (modules_sym == sym) {
 390                         sym_set_all_changed();
 391                         modules_val = modules_sym->curr.tri;
 392                 }
 393         }
 394
 395         if (sym_is_choice(sym)) {
 396                 struct symbol *choice_sym;
 397
 398                 prop = sym_get_choice_prop(sym);
 399                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
 400                         if ((sym->flags & SYMBOL_WRITE) &&
 401                             choice_sym->visible != no)
 402                                 choice_sym->flags |= SYMBOL_WRITE;
 403                         if (sym->flags & SYMBOL_CHANGED)
 404                                 sym_set_changed(choice_sym);
 405                 }
 406         }
 407
 408         if (sym->flags & SYMBOL_AUTO)
 409                 sym->flags &= ~SYMBOL_WRITE;
 410 }
 411
 412 void sym_clear_all_valid(void)
 413 {
 414         struct symbol *sym;
 415         int i;
 416
 417         for_all_symbols(i, sym)
 418                 sym->flags &= ~SYMBOL_VALID;
 419         sym_add_change_count(1);
 420         if (modules_sym)
 421                 sym_calc_value(modules_sym);
 422 }
 423
 424 void sym_set_changed(struct symbol *sym)
 425 {
 426         struct property *prop;
 427
 428         sym->flags |= SYMBOL_CHANGED;
 429         for (prop = sym->prop; prop; prop = prop->next) {
 430                 if (prop->menu)
 431                         prop->menu->flags |= MENU_CHANGED;
 432         }
 433 }
 434
 435 void sym_set_all_changed(void)
 436 {
 437         struct symbol *sym;
 438         int i;
 439
 440         for_all_symbols(i, sym)
 441                 sym_set_changed(sym);
 442 }
 443
 444 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 445 {
 446         int type = sym_get_type(sym);
 447
 448         if (sym->visible == no)
 449                 return false;
 450
 451         if (type != S_BOOLEAN && type != S_TRISTATE)
 452                 return false;
 453
 454         if (type == S_BOOLEAN && val == mod)
 455                 return false;
 456         if (sym->visible <= sym->rev_dep.tri)
 457                 return false;
 458         if (sym_is_choice_value(sym) && sym->visible == yes)
 459                 return val == yes;
 460         return val >= sym->rev_dep.tri && val <= sym->visible;
 461 }
 462
 463 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 464 {
 465         tristate oldval = sym_get_tristate_value(sym);
 466
 467         if (oldval != val && !sym_tristate_within_range(sym, val))
 468                 return false;
 469
 470         if (!(sym->flags & SYMBOL_DEF_USER)) {
 471                 sym->flags |= SYMBOL_DEF_USER;
 472                 sym_set_changed(sym);
 473         }
 474         /*
 475          * setting a choice value also resets the new flag of the choice
 476          * symbol and all other choice values.
 477          */
 478         if (sym_is_choice_value(sym) && val == yes) {
 479                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 480                 struct property *prop;
 481                 struct expr *e;
 482
 483                 cs->def[S_DEF_USER].val = sym;
 484                 cs->flags |= SYMBOL_DEF_USER;
 485                 prop = sym_get_choice_prop(cs);
 486                 for (e = prop->expr; e; e = e->left.expr) {
 487                         if (e->right.sym->visible != no)
 488                                 e->right.sym->flags |= SYMBOL_DEF_USER;
 489                 }
 490         }
 491
 492         sym->def[S_DEF_USER].tri = val;
 493         if (oldval != val)
 494                 sym_clear_all_valid();
 495
 496         return true;
 497 }
 498
 499 tristate sym_toggle_tristate_value(struct symbol *sym)
 500 {
 501         tristate oldval, newval;
 502
 503         oldval = newval = sym_get_tristate_value(sym);
 504         do {
 505                 switch (newval) {
 506                 case no:
 507                         newval = mod;
 508                         break;
 509                 case mod:
 510                         newval = yes;
 511                         break;
 512                 case yes:
 513                         newval = no;
 514                         break;
 515                 }
 516                 if (sym_set_tristate_value(sym, newval))
 517                         break;
 518         } while (oldval != newval);
 519         return newval;
 520 }
 521
 522 bool sym_string_valid(struct symbol *sym, const char *str)
 523 {
 524         signed char ch;
 525
 526         switch (sym->type) {
 527         case S_STRING:
 528                 return true;
 529         case S_INT:
 530                 ch = *str++;
 531                 if (ch == '-')
 532                         ch = *str++;
 533                 if (!isdigit(ch))
 534                         return false;
 535                 if (ch == '0' && *str != 0)
 536                         return false;
 537                 while ((ch = *str++)) {
 538                         if (!isdigit(ch))
 539                                 return false;
 540                 }
 541                 return true;
 542         case S_HEX:
 543                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 544                         str += 2;
 545                 ch = *str++;
 546                 do {
 547                         if (!isxdigit(ch))
 548                                 return false;
 549                 } while ((ch = *str++));
 550                 return true;
 551         case S_BOOLEAN:
 552         case S_TRISTATE:
 553                 switch (str[0]) {
 554                 case 'y': case 'Y':
 555                 case 'm': case 'M':
 556                 case 'n': case 'N':
 557                         return true;
 558                 }
 559                 return false;
 560         default:
 561                 return false;
 562         }
 563 }
 564
 565 bool sym_string_within_range(struct symbol *sym, const char *str)
 566 {
 567         struct property *prop;
 568         int val;
 569
 570         switch (sym->type) {
 571         case S_STRING:
 572                 return sym_string_valid(sym, str);
 573         case S_INT:
 574                 if (!sym_string_valid(sym, str))
 575                         return false;
 576                 prop = sym_get_range_prop(sym);
 577                 if (!prop)
 578                         return true;
 579                 val = strtol(str, NULL, 10);
 580                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 581                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 582         case S_HEX:
 583                 if (!sym_string_valid(sym, str))
 584                         return false;
 585                 prop = sym_get_range_prop(sym);
 586                 if (!prop)
 587                         return true;
 588                 val = strtol(str, NULL, 16);
 589                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 590                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 591         case S_BOOLEAN:
 592         case S_TRISTATE:
 593                 switch (str[0]) {
 594                 case 'y': case 'Y':
 595                         return sym_tristate_within_range(sym, yes);
 596                 case 'm': case 'M':
 597                         return sym_tristate_within_range(sym, mod);
 598                 case 'n': case 'N':
 599                         return sym_tristate_within_range(sym, no);
 600                 }
 601                 return false;
 602         default:
 603                 return false;
 604         }
 605 }
 606
 607 bool sym_set_string_value(struct symbol *sym, const char *newval)
 608 {
 609         const char *oldval;
 610         char *val;
 611         int size;
 612
 613         switch (sym->type) {
 614         case S_BOOLEAN:
 615         case S_TRISTATE:
 616                 switch (newval[0]) {
 617                 case 'y': case 'Y':
 618                         return sym_set_tristate_value(sym, yes);
 619                 case 'm': case 'M':
 620                         return sym_set_tristate_value(sym, mod);
 621                 case 'n': case 'N':
 622                         return sym_set_tristate_value(sym, no);
 623                 }
 624                 return false;
 625         default:
 626                 ;
 627         }
 628
 629         if (!sym_string_within_range(sym, newval))
 630                 return false;
 631
 632         if (!(sym->flags & SYMBOL_DEF_USER)) {
 633                 sym->flags |= SYMBOL_DEF_USER;
 634                 sym_set_changed(sym);
 635         }
 636
 637         oldval = sym->def[S_DEF_USER].val;
 638         size = strlen(newval) + 1;
 639         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 640                 size += 2;
 641                 sym->def[S_DEF_USER].val = val = malloc(size);
 642                 *val++ = '0';
 643                 *val++ = 'x';
 644         } else if (!oldval || strcmp(oldval, newval))
 645                 sym->def[S_DEF_USER].val = val = malloc(size);
 646         else
 647                 return true;
 648
 649         strcpy(val, newval);
 650         free((void *)oldval);
 651         sym_clear_all_valid();
 652
 653         return true;
 654 }
 655
 656 /*
 657  * Find the default value associated to a symbol.
 658  * For tristate symbol handle the modules=n case
 659  * in which case "m" becomes "y".
 660  * If the symbol does not have any default then fallback
 661  * to the fixed default values.
 662  */
 663 const char *sym_get_string_default(struct symbol *sym)
 664 {
 665         struct property *prop;
 666         struct symbol *ds;
 667         const char *str;
 668         tristate val;
 669
 670         sym_calc_visibility(sym);
 671         sym_calc_value(modules_sym);
 672         val = symbol_no.curr.tri;
 673         str = symbol_empty.curr.val;
 674
 675         /* If symbol has a default value look it up */
 676         prop = sym_get_default_prop(sym);
 677         if (prop != NULL) {
 678                 switch (sym->type) {
 679                 case S_BOOLEAN:
 680                 case S_TRISTATE:
 681                         /* The visibility imay limit the value from yes => mod */
 682                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 683                         break;
 684                 default:
 685                         /*
 686                          * The following fails to handle the situation
 687                          * where a default value is further limited by
 688                          * the valid range.
 689                          */
 690                         ds = prop_get_symbol(prop);
 691                         if (ds != NULL) {
 692                                 sym_calc_value(ds);
 693                                 str = (const char *)ds->curr.val;
 694                         }
 695                 }
 696         }
 697
 698         /* Handle select statements */
 699         val = EXPR_OR(val, sym->rev_dep.tri);
 700
 701         /* transpose mod to yes if modules are not enabled */
 702         if (val == mod)
 703                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 704                         val = yes;
 705
 706         /* transpose mod to yes if type is bool */
 707         if (sym->type == S_BOOLEAN && val == mod)
 708                 val = yes;
 709
 710         switch (sym->type) {
 711         case S_BOOLEAN:
 712         case S_TRISTATE:
 713                 switch (val) {
 714                 case no: return "n";
 715                 case mod: return "m";
 716                 case yes: return "y";
 717                 }
 718         case S_INT:
 719         case S_HEX:
 720                 return str;
 721         case S_STRING:
 722                 return str;
 723         case S_OTHER:
 724         case S_UNKNOWN:
 725                 break;
 726         }
 727         return "";
 728 }
 729
 730 const char *sym_get_string_value(struct symbol *sym)
 731 {
 732         tristate val;
 733
 734         switch (sym->type) {
 735         case S_BOOLEAN:
 736         case S_TRISTATE:
 737                 val = sym_get_tristate_value(sym);
 738                 switch (val) {
 739                 case no:
 740                         return "n";
 741                 case mod:
 742                         return "m";
 743                 case yes:
 744                         return "y";
 745                 }
 746                 break;
 747         default:
 748                 ;
 749         }
 750         return (const char *)sym->curr.val;
 751 }
 752
 753 bool sym_is_changable(struct symbol *sym)
 754 {
 755         return sym->visible > sym->rev_dep.tri;
 756 }
 757
 758 static unsigned strhash(const char *s)
 759 {
 760         /* fnv32 hash */
 761         unsigned hash = 2166136261U;
 762         for (; *s; s++)
 763                 hash = (hash ^ *s) * 0x01000193;
 764         return hash;
 765 }
 766
 767 struct symbol *sym_lookup(const char *name, int flags)
 768 {
 769         struct symbol *symbol;
 770         char *new_name;
 771         int hash;
 772
 773         if (name) {
 774                 if (name[0] && !name[1]) {
 775                         switch (name[0]) {
 776                         case 'y': return &symbol_yes;
 777                         case 'm': return &symbol_mod;
 778                         case 'n': return &symbol_no;
 779                         }
 780                 }
 781                 hash = strhash(name) % SYMBOL_HASHSIZE;
 782
 783                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 784                         if (symbol->name &&
 785                             !strcmp(symbol->name, name) &&
 786                             (flags ? symbol->flags & flags
 787                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 788                                 return symbol;
 789                 }
 790                 new_name = strdup(name);
 791         } else {
 792                 new_name = NULL;
 793                 hash = 0;
 794         }
 795
 796         symbol = malloc(sizeof(*symbol));
 797         memset(symbol, 0, sizeof(*symbol));
 798         symbol->name = new_name;
 799         symbol->type = S_UNKNOWN;
 800         symbol->flags |= flags;
 801
 802         symbol->next = symbol_hash[hash];
 803         symbol_hash[hash] = symbol;
 804
 805         return symbol;
 806 }
 807
 808 struct symbol *sym_find(const char *name)
 809 {
 810         struct symbol *symbol = NULL;
 811         int hash = 0;
 812
 813         if (!name)
 814                 return NULL;
 815
 816         if (name[0] && !name[1]) {
 817                 switch (name[0]) {
 818                 case 'y': return &symbol_yes;
 819                 case 'm': return &symbol_mod;
 820                 case 'n': return &symbol_no;
 821                 }
 822         }
 823         hash = strhash(name) % SYMBOL_HASHSIZE;
 824
 825         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 826                 if (symbol->name &&
 827                     !strcmp(symbol->name, name) &&
 828                     !(symbol->flags & SYMBOL_CONST))
 829                                 break;
 830         }
 831
 832         return symbol;
 833 }
 834
 835 struct symbol **sym_re_search(const char *pattern)
 836 {
 837         struct symbol *sym, **sym_arr = NULL;
 838         int i, cnt, size;
 839         regex_t re;
 840
 841         cnt = size = 0;
 842         /* Skip if empty */
 843         if (strlen(pattern) == 0)
 844                 return NULL;
 845         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
 846                 return NULL;
 847
 848         for_all_symbols(i, sym) {
 849                 if (sym->flags & SYMBOL_CONST || !sym->name)
 850                         continue;
 851                 if (regexec(&re, sym->name, 0, NULL, 0))
 852                         continue;
 853                 if (cnt + 1 >= size) {
 854                         void *tmp = sym_arr;
 855                         size += 16;
 856                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
 857                         if (!sym_arr) {
 858                                 free(tmp);
 859                                 return NULL;
 860                         }
 861                 }
 862                 sym_calc_value(sym);
 863                 sym_arr[cnt++] = sym;
 864         }
 865         if (sym_arr)
 866                 sym_arr[cnt] = NULL;
 867         regfree(&re);
 868
 869         return sym_arr;
 870 }
 871
 872 /*
 873  * When we check for recursive dependencies we use a stack to save
 874  * current state so we can print out relevant info to user.
 875  * The entries are located on the call stack so no need to free memory.
 876  * Note inser() remove() must always match to properly clear the stack.
 877  */
 878 static struct dep_stack {
 879         struct dep_stack *prev, *next;
 880         struct symbol *sym;
 881         struct property *prop;
 882         struct expr *expr;
 883 } *check_top;
 884
 885 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
 886 {
 887         memset(stack, 0, sizeof(*stack));
 888         if (check_top)
 889                 check_top->next = stack;
 890         stack->prev = check_top;
 891         stack->sym = sym;
 892         check_top = stack;
 893 }
 894
 895 static void dep_stack_remove(void)
 896 {
 897         check_top = check_top->prev;
 898         if (check_top)
 899                 check_top->next = NULL;
 900 }
 901
 902 /*
 903  * Called when we have detected a recursive dependency.
 904  * check_top point to the top of the stact so we use
 905  * the ->prev pointer to locate the bottom of the stack.
 906  */
 907 static void sym_check_print_recursive(struct symbol *last_sym)
 908 {
 909         struct dep_stack *stack;
 910         struct symbol *sym, *next_sym;
 911         struct menu *menu = NULL;
 912         struct property *prop;
 913         struct dep_stack cv_stack;
 914
 915         if (sym_is_choice_value(last_sym)) {
 916                 dep_stack_insert(&cv_stack, last_sym);
 917                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
 918         }
 919
 920         for (stack = check_top; stack != NULL; stack = stack->prev)
 921                 if (stack->sym == last_sym)
 922                         break;
 923         if (!stack) {
 924                 fprintf(stderr, "unexpected recursive dependency error\n");
 925                 return;
 926         }
 927
 928         for (; stack; stack = stack->next) {
 929                 sym = stack->sym;
 930                 next_sym = stack->next ? stack->next->sym : last_sym;
 931                 prop = stack->prop;
 932                 if (prop == NULL)
 933                         prop = stack->sym->prop;
 934
 935                 /* for choice values find the menu entry (used below) */
 936                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
 937                         for (prop = sym->prop; prop; prop = prop->next) {
 938                                 menu = prop->menu;
 939                                 if (prop->menu)
 940                                         break;
 941                         }
 942                 }
 943                 if (stack->sym == last_sym)
 944                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
 945                                 prop->file->name, prop->lineno);
 946                 if (stack->expr) {
 947                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
 948                                 prop->file->name, prop->lineno,
 949                                 sym->name ? sym->name : "<choice>",
 950                                 prop_get_type_name(prop->type),
 951                                 next_sym->name ? next_sym->name : "<choice>");
 952                 } else if (stack->prop) {
 953                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
 954                                 prop->file->name, prop->lineno,
 955                                 sym->name ? sym->name : "<choice>",
 956                                 next_sym->name ? next_sym->name : "<choice>");
 957                 } else if (sym_is_choice(sym)) {
 958                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
 959                                 menu->file->name, menu->lineno,
 960                                 sym->name ? sym->name : "<choice>",
 961                                 next_sym->name ? next_sym->name : "<choice>");
 962                 } else if (sym_is_choice_value(sym)) {
 963                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
 964                                 menu->file->name, menu->lineno,
 965                                 sym->name ? sym->name : "<choice>",
 966                                 next_sym->name ? next_sym->name : "<choice>");
 967                 } else {
 968                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
 969                                 prop->file->name, prop->lineno,
 970                                 sym->name ? sym->name : "<choice>",
 971                                 next_sym->name ? next_sym->name : "<choice>");
 972                 }
 973         }
 974
 975         if (check_top == &cv_stack)
 976                 dep_stack_remove();
 977 }
 978
 979 static struct symbol *sym_check_expr_deps(struct expr *e)
 980 {
 981         struct symbol *sym;
 982
 983         if (!e)
 984                 return NULL;
 985         switch (e->type) {
 986         case E_OR:
 987         case E_AND:
 988                 sym = sym_check_expr_deps(e->left.expr);
 989                 if (sym)
 990                         return sym;
 991                 return sym_check_expr_deps(e->right.expr);
 992         case E_NOT:
 993                 return sym_check_expr_deps(e->left.expr);
 994         case E_EQUAL:
 995         case E_UNEQUAL:
 996                 sym = sym_check_deps(e->left.sym);
 997                 if (sym)
 998                         return sym;
 999                 return sym_check_deps(e->right.sym);
1000         case E_SYMBOL:
1001                 return sym_check_deps(e->left.sym);
1002         default:
1003                 break;
1004         }
1005         printf("Oops! How to check %d?\n", e->type);
1006         return NULL;
1007 }
1008
1009 /* return NULL when dependencies are OK */
1010 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1011 {
1012         struct symbol *sym2;
1013         struct property *prop;
1014         struct dep_stack stack;
1015
1016         dep_stack_insert(&stack, sym);
1017
1018         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1019         if (sym2)
1020                 goto out;
1021
1022         for (prop = sym->prop; prop; prop = prop->next) {
1023                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1024                         continue;
1025                 stack.prop = prop;
1026                 sym2 = sym_check_expr_deps(prop->visible.expr);
1027                 if (sym2)
1028                         break;
1029                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1030                         continue;
1031                 stack.expr = prop->expr;
1032                 sym2 = sym_check_expr_deps(prop->expr);
1033                 if (sym2)
1034                         break;
1035                 stack.expr = NULL;
1036         }
1037
1038 out:
1039         dep_stack_remove();
1040
1041         return sym2;
1042 }
1043
1044 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1045 {
1046         struct symbol *sym, *sym2;
1047         struct property *prop;
1048         struct expr *e;
1049         struct dep_stack stack;
1050
1051         dep_stack_insert(&stack, choice);
1052
1053         prop = sym_get_choice_prop(choice);
1054         expr_list_for_each_sym(prop->expr, e, sym)
1055                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1056
1057         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1058         sym2 = sym_check_sym_deps(choice);
1059         choice->flags &= ~SYMBOL_CHECK;
1060         if (sym2)
1061                 goto out;
1062
1063         expr_list_for_each_sym(prop->expr, e, sym) {
1064                 sym2 = sym_check_sym_deps(sym);
1065                 if (sym2)
1066                         break;
1067         }
1068 out:
1069         expr_list_for_each_sym(prop->expr, e, sym)
1070                 sym->flags &= ~SYMBOL_CHECK;
1071
1072         if (sym2 && sym_is_choice_value(sym2) &&
1073             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1074                 sym2 = choice;
1075
1076         dep_stack_remove();
1077
1078         return sym2;
1079 }
1080
1081 struct symbol *sym_check_deps(struct symbol *sym)
1082 {
1083         struct symbol *sym2;
1084         struct property *prop;
1085
1086         if (sym->flags & SYMBOL_CHECK) {
1087                 sym_check_print_recursive(sym);
1088                 return sym;
1089         }
1090         if (sym->flags & SYMBOL_CHECKED)
1091                 return NULL;
1092
1093         if (sym_is_choice_value(sym)) {
1094                 struct dep_stack stack;
1095
1096                 /* for choice groups start the check with main choice symbol */
1097                 dep_stack_insert(&stack, sym);
1098                 prop = sym_get_choice_prop(sym);
1099                 sym2 = sym_check_deps(prop_get_symbol(prop));
1100                 dep_stack_remove();
1101         } else if (sym_is_choice(sym)) {
1102                 sym2 = sym_check_choice_deps(sym);
1103         } else {
1104                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1105                 sym2 = sym_check_sym_deps(sym);
1106                 sym->flags &= ~SYMBOL_CHECK;
1107         }
1108
1109         if (sym2 && sym2 == sym)
1110                 sym2 = NULL;
1111
1112         return sym2;
1113 }
1114
1115 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1116 {
1117         struct property *prop;
1118         struct property **propp;
1119
1120         prop = malloc(sizeof(*prop));
1121         memset(prop, 0, sizeof(*prop));
1122         prop->type = type;
1123         prop->sym = sym;
1124         prop->file = current_file;
1125         prop->lineno = zconf_lineno();
1126
1127         /* append property to the prop list of symbol */
1128         if (sym) {
1129                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1130                         ;
1131                 *propp = prop;
1132         }
1133
1134         return prop;
1135 }
1136
1137 struct symbol *prop_get_symbol(struct property *prop)
1138 {
1139         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1140                            prop->expr->type == E_LIST))
1141                 return prop->expr->left.sym;
1142         return NULL;
1143 }
1144
1145 const char *prop_get_type_name(enum prop_type type)
1146 {
1147         switch (type) {
1148         case P_PROMPT:
1149                 return "prompt";
1150         case P_ENV:
1151                 return "env";
1152         case P_COMMENT:
1153                 return "comment";
1154         case P_MENU:
1155                 return "menu";
1156         case P_DEFAULT:
1157                 return "default";
1158         case P_CHOICE:
1159                 return "choice";
1160         case P_SELECT:
1161                 return "select";
1162         case P_RANGE:
1163                 return "range";
1164         case P_SYMBOL:
1165                 return "symbol";
1166         case P_UNKNOWN:
1167                 break;
1168         }
1169         return "unknown";
1170 }
1171
1172 static void prop_add_env(const char *env)
1173 {
1174         struct symbol *sym, *sym2;
1175         struct property *prop;
1176         char *p;
1177
1178         sym = current_entry->sym;
1179         sym->flags |= SYMBOL_AUTO;
1180         for_all_properties(sym, prop, P_ENV) {
1181                 sym2 = prop_get_symbol(prop);
1182                 if (strcmp(sym2->name, env))
1183                         menu_warn(current_entry, "redefining environment symbol from %s",
1184                                   sym2->name);
1185                 return;
1186         }
1187
1188         prop = prop_alloc(P_ENV, sym);
1189         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1190
1191         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1192         sym_env_list->right.sym = sym;
1193
1194         p = getenv(env);
1195         if (p)
1196                 sym_add_default(sym, p);
1197         else
1198                 menu_warn(current_entry, "environment variable %s undefined", env);
1199 }