scripts/config/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_YES|SYMBOL_VALID,
  19 }, symbol_mod = {
  20         .name = "m",
  21         .curr = { "m", mod },
  22         .flags = SYMBOL_MOD|SYMBOL_VALID,
  23 }, symbol_no = {
  24         .name = "n",
  25         .curr = { "n", no },
  26         .flags = SYMBOL_NO|SYMBOL_VALID,
  27 }, symbol_empty = {
  28         .name = "",
  29         .curr = { "", no },
  30         .flags = SYMBOL_VALID,
  31 };
  32
  33 int sym_change_count;
  34 struct symbol *modules_sym;
  35 tristate modules_val;
  36
  37 void sym_add_default(struct symbol *sym, const char *def)
  38 {
  39         struct property *prop = prop_alloc(P_DEFAULT, sym);
  40
  41         prop->expr = expr_alloc_symbol(sym_lookup(def, 1));
  42 }
  43
  44 void sym_init(void)
  45 {
  46         struct symbol *sym;
  47         struct utsname uts;
  48         char *p;
  49         static bool inited = false;
  50
  51         if (inited)
  52                 return;
  53         inited = true;
  54
  55         uname(&uts);
  56
  57         sym = sym_lookup("ARCH", 0);
  58         sym->type = S_STRING;
  59         sym->flags |= SYMBOL_AUTO;
  60         p = getenv("ARCH");
  61         if (p)
  62                 sym_add_default(sym, p);
  63
  64         sym = sym_lookup("OPENWRTVERSION", 0);
  65         sym->type = S_STRING;
  66         sym->flags |= SYMBOL_AUTO;
  67         p = getenv("OPENWRTVERSION");
  68         if (p)
  69                 sym_add_default(sym, p);
  70
  71         sym = sym_lookup("UNAME_RELEASE", 0);
  72         sym->type = S_STRING;
  73         sym->flags |= SYMBOL_AUTO;
  74         sym_add_default(sym, uts.release);
  75 }
  76
  77 enum symbol_type sym_get_type(struct symbol *sym)
  78 {
  79         enum symbol_type type = sym->type;
  80
  81         if (type == S_TRISTATE) {
  82                 if (sym_is_choice_value(sym) && sym->visible == yes)
  83                         type = S_BOOLEAN;
  84 /* tristate always enabled */
  85 #if 0
  86                 else if (modules_val == no)
  87                         type = S_BOOLEAN;
  88 #endif
  89         }
  90         return type;
  91 }
  92
  93 const char *sym_type_name(enum symbol_type type)
  94 {
  95         switch (type) {
  96         case S_BOOLEAN:
  97                 return "boolean";
  98         case S_TRISTATE:
  99                 return "tristate";
 100         case S_INT:
 101                 return "integer";
 102         case S_HEX:
 103                 return "hex";
 104         case S_STRING:
 105                 return "string";
 106         case S_UNKNOWN:
 107                 return "unknown";
 108         case S_OTHER:
 109                 break;
 110         }
 111         return "???";
 112 }
 113
 114 struct property *sym_get_choice_prop(struct symbol *sym)
 115 {
 116         struct property *prop;
 117
 118         for_all_choices(sym, prop)
 119                 return prop;
 120         return NULL;
 121 }
 122
 123 struct property *sym_get_default_prop(struct symbol *sym)
 124 {
 125         struct property *prop;
 126
 127         for_all_defaults(sym, prop) {
 128                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 129                 if (prop->visible.tri != no)
 130                         return prop;
 131         }
 132         return NULL;
 133 }
 134
 135 struct property *sym_get_range_prop(struct symbol *sym)
 136 {
 137         struct property *prop;
 138
 139         for_all_properties(sym, prop, P_RANGE) {
 140                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 141                 if (prop->visible.tri != no)
 142                         return prop;
 143         }
 144         return NULL;
 145 }
 146
 147 static int sym_get_range_val(struct symbol *sym, int base)
 148 {
 149         sym_calc_value(sym);
 150         switch (sym->type) {
 151         case S_INT:
 152                 base = 10;
 153                 break;
 154         case S_HEX:
 155                 base = 16;
 156                 break;
 157         default:
 158                 break;
 159         }
 160         return strtol(sym->curr.val, NULL, base);
 161 }
 162
 163 static void sym_validate_range(struct symbol *sym)
 164 {
 165         struct property *prop;
 166         int base, val, val2;
 167         char str[64];
 168
 169         switch (sym->type) {
 170         case S_INT:
 171                 base = 10;
 172                 break;
 173         case S_HEX:
 174                 base = 16;
 175                 break;
 176         default:
 177                 return;
 178         }
 179         prop = sym_get_range_prop(sym);
 180         if (!prop)
 181                 return;
 182         val = strtol(sym->curr.val, NULL, base);
 183         val2 = sym_get_range_val(prop->expr->left.sym, base);
 184         if (val >= val2) {
 185                 val2 = sym_get_range_val(prop->expr->right.sym, base);
 186                 if (val <= val2)
 187                         return;
 188         }
 189         if (sym->type == S_INT)
 190                 sprintf(str, "%d", val2);
 191         else
 192                 sprintf(str, "0x%x", val2);
 193         sym->curr.val = strdup(str);
 194 }
 195
 196 static void sym_calc_visibility(struct symbol *sym)
 197 {
 198         struct property *prop;
 199         tristate tri;
 200
 201         /* any prompt visible? */
 202         tri = no;
 203         for_all_prompts(sym, prop) {
 204                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 205                 tri = E_OR(tri, prop->visible.tri);
 206         }
 207 /* tristate always enabled */
 208 #if 0
 209         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 210 #else
 211         if (tri == mod && (sym->type != S_TRISTATE))
 212 #endif
 213                 tri = yes;
 214         if (sym->visible != tri) {
 215                 sym->visible = tri;
 216                 sym_set_changed(sym);
 217         }
 218         if (sym_is_choice_value(sym))
 219                 return;
 220         tri = no;
 221         if (sym->rev_dep.expr)
 222                 tri = expr_calc_value(sym->rev_dep.expr);
 223         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 224                 tri = yes;
 225         if (sym->rev_dep.tri != tri) {
 226                 sym->rev_dep.tri = tri;
 227                 sym_set_changed(sym);
 228         }
 229 }
 230
 231 static struct symbol *sym_calc_choice(struct symbol *sym)
 232 {
 233         struct symbol *def_sym;
 234         struct property *prop;
 235         struct expr *e;
 236
 237         /* is the user choice visible? */
 238         def_sym = sym->user.val;
 239         if (def_sym) {
 240                 sym_calc_visibility(def_sym);
 241                 if (def_sym->visible != no)
 242                         return def_sym;
 243         }
 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                 sym_calc_visibility(def_sym);
 252                 if (def_sym->visible != no)
 253                         return def_sym;
 254         }
 255
 256         /* just get the first visible value */
 257         prop = sym_get_choice_prop(sym);
 258         for (e = prop->expr; e; e = e->left.expr) {
 259                 def_sym = e->right.sym;
 260                 sym_calc_visibility(def_sym);
 261                 if (def_sym->visible != no)
 262                         return def_sym;
 263         }
 264
 265         /* no choice? reset tristate value */
 266         sym->curr.tri = no;
 267         return NULL;
 268 }
 269
 270 void sym_calc_value(struct symbol *sym)
 271 {
 272         struct symbol_value newval, oldval;
 273         struct property *prop;
 274         struct expr *e;
 275
 276         if (!sym)
 277                 return;
 278
 279         if (sym->flags & SYMBOL_VALID)
 280                 return;
 281         sym->flags |= SYMBOL_VALID;
 282
 283         oldval = sym->curr;
 284
 285         switch (sym->type) {
 286         case S_INT:
 287         case S_HEX:
 288         case S_STRING:
 289                 newval = symbol_empty.curr;
 290                 break;
 291         case S_BOOLEAN:
 292         case S_TRISTATE:
 293                 newval = symbol_no.curr;
 294                 break;
 295         default:
 296                 sym->curr.val = sym->name;
 297                 sym->curr.tri = no;
 298                 return;
 299         }
 300         if (!sym_is_choice_value(sym))
 301                 sym->flags &= ~SYMBOL_WRITE;
 302
 303         sym_calc_visibility(sym);
 304
 305         /* set default if recursively called */
 306         sym->curr = newval;
 307
 308         switch (sym_get_type(sym)) {
 309         case S_BOOLEAN:
 310         case S_TRISTATE:
 311                 if (sym_is_choice_value(sym) && sym->visible == yes) {
 312                         prop = sym_get_choice_prop(sym);
 313                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 314                 } else if (E_OR(sym->visible, sym->rev_dep.tri) != no) {
 315                         sym->flags |= SYMBOL_WRITE;
 316                         if (sym_has_value(sym))
 317                                 newval.tri = sym->user.tri;
 318                         else if (!sym_is_choice(sym)) {
 319                                 prop = sym_get_default_prop(sym);
 320                                 if (prop)
 321                                         newval.tri = expr_calc_value(prop->expr);
 322                         }
 323                         newval.tri = E_OR(E_AND(newval.tri, sym->visible), sym->rev_dep.tri);
 324                 } else if (!sym_is_choice(sym)) {
 325                         prop = sym_get_default_prop(sym);
 326                         if (prop) {
 327                                 sym->flags |= SYMBOL_WRITE;
 328                                 newval.tri = expr_calc_value(prop->expr);
 329                         }
 330                 }
 331                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 332                         newval.tri = yes;
 333                 break;
 334         case S_STRING:
 335         case S_HEX:
 336         case S_INT:
 337                 if (sym->visible != no) {
 338                         sym->flags |= SYMBOL_WRITE;
 339                         if (sym_has_value(sym)) {
 340                                 newval.val = sym->user.val;
 341                                 break;
 342                         }
 343                 }
 344                 prop = sym_get_default_prop(sym);
 345                 if (prop) {
 346                         struct symbol *ds = prop_get_symbol(prop);
 347                         if (ds) {
 348                                 sym->flags |= SYMBOL_WRITE;
 349                                 sym_calc_value(ds);
 350                                 newval.val = ds->curr.val;
 351                         }
 352                 }
 353                 break;
 354         default:
 355                 ;
 356         }
 357
 358         sym->curr = newval;
 359         if (sym_is_choice(sym) && newval.tri == yes)
 360                 sym->curr.val = sym_calc_choice(sym);
 361         sym_validate_range(sym);
 362
 363         if (memcmp(&oldval, &sym->curr, sizeof(oldval)))
 364                 sym_set_changed(sym);
 365
 366         if (modules_sym == sym)
 367                 modules_val = modules_sym->curr.tri;
 368
 369         if (sym_is_choice(sym)) {
 370                 int flags = sym->flags & (SYMBOL_CHANGED | SYMBOL_WRITE);
 371                 prop = sym_get_choice_prop(sym);
 372                 for (e = prop->expr; e; e = e->left.expr) {
 373                         e->right.sym->flags |= flags;
 374                         if (flags & SYMBOL_CHANGED)
 375                                 sym_set_changed(e->right.sym);
 376                 }
 377         }
 378 }
 379
 380 void sym_clear_all_valid(void)
 381 {
 382         struct symbol *sym;
 383         int i;
 384
 385         for_all_symbols(i, sym)
 386                 sym->flags &= ~SYMBOL_VALID;
 387         sym_change_count++;
 388         if (modules_sym)
 389                 sym_calc_value(modules_sym);
 390 }
 391
 392 void sym_set_changed(struct symbol *sym)
 393 {
 394         struct property *prop;
 395
 396         sym->flags |= SYMBOL_CHANGED;
 397         for (prop = sym->prop; prop; prop = prop->next) {
 398                 if (prop->menu)
 399                         prop->menu->flags |= MENU_CHANGED;
 400         }
 401 }
 402
 403 void sym_set_all_changed(void)
 404 {
 405         struct symbol *sym;
 406         int i;
 407
 408         for_all_symbols(i, sym)
 409                 sym_set_changed(sym);
 410 }
 411
 412 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 413 {
 414         int type = sym_get_type(sym);
 415
 416         if (sym->visible == no)
 417                 return false;
 418
 419         if (type != S_BOOLEAN && type != S_TRISTATE)
 420                 return false;
 421
 422         if (type == S_BOOLEAN && val == mod)
 423                 return false;
 424         if (sym->visible <= sym->rev_dep.tri)
 425                 return false;
 426         if (sym_is_choice_value(sym) && sym->visible == yes)
 427                 return val == yes;
 428         return val >= sym->rev_dep.tri && val <= sym->visible;
 429 }
 430
 431 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 432 {
 433         tristate oldval = sym_get_tristate_value(sym);
 434
 435         if (oldval != val && !sym_tristate_within_range(sym, val))
 436                 return false;
 437
 438         if (sym->flags & SYMBOL_NEW) {
 439                 sym->flags &= ~SYMBOL_NEW;
 440                 sym_set_changed(sym);
 441         }
 442         /*
 443          * setting a choice value also resets the new flag of the choice
 444          * symbol and all other choice values.
 445          */
 446         if (sym_is_choice_value(sym) && val == yes) {
 447                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 448                 struct property *prop;
 449                 struct expr *e;
 450
 451                 cs->user.val = sym;
 452                 cs->flags &= ~SYMBOL_NEW;
 453                 prop = sym_get_choice_prop(cs);
 454                 for (e = prop->expr; e; e = e->left.expr) {
 455                         if (e->right.sym->visible != no)
 456                                 e->right.sym->flags &= ~SYMBOL_NEW;
 457                 }
 458         }
 459
 460         sym->user.tri = val;
 461         if (oldval != val) {
 462                 sym_clear_all_valid();
 463                 if (sym == modules_sym)
 464                         sym_set_all_changed();
 465         }
 466
 467         return true;
 468 }
 469
 470 tristate sym_toggle_tristate_value(struct symbol *sym)
 471 {
 472         tristate oldval, newval;
 473
 474         oldval = newval = sym_get_tristate_value(sym);
 475         do {
 476                 switch (newval) {
 477                 case no:
 478                         newval = mod;
 479                         break;
 480                 case mod:
 481                         newval = yes;
 482                         break;
 483                 case yes:
 484                         newval = no;
 485                         break;
 486                 }
 487                 if (sym_set_tristate_value(sym, newval))
 488                         break;
 489         } while (oldval != newval);
 490         return newval;
 491 }
 492
 493 bool sym_string_valid(struct symbol *sym, const char *str)
 494 {
 495         signed char ch;
 496
 497         switch (sym->type) {
 498         case S_STRING:
 499                 return true;
 500         case S_INT:
 501                 ch = *str++;
 502                 if (ch == '-')
 503                         ch = *str++;
 504                 if (!isdigit(ch))
 505                         return false;
 506                 if (ch == '0' && *str != 0)
 507                         return false;
 508                 while ((ch = *str++)) {
 509                         if (!isdigit(ch))
 510                                 return false;
 511                 }
 512                 return true;
 513         case S_HEX:
 514                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 515                         str += 2;
 516                 ch = *str++;
 517                 do {
 518                         if (!isxdigit(ch))
 519                                 return false;
 520                 } while ((ch = *str++));
 521                 return true;
 522         case S_BOOLEAN:
 523         case S_TRISTATE:
 524                 switch (str[0]) {
 525                 case 'y': case 'Y':
 526                 case 'm': case 'M':
 527                 case 'n': case 'N':
 528                         return true;
 529                 }
 530                 return false;
 531         default:
 532                 return false;
 533         }
 534 }
 535
 536 bool sym_string_within_range(struct symbol *sym, const char *str)
 537 {
 538         struct property *prop;
 539         int val;
 540
 541         switch (sym->type) {
 542         case S_STRING:
 543                 return sym_string_valid(sym, str);
 544         case S_INT:
 545                 if (!sym_string_valid(sym, str))
 546                         return false;
 547                 prop = sym_get_range_prop(sym);
 548                 if (!prop)
 549                         return true;
 550                 val = strtol(str, NULL, 10);
 551                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 552                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 553         case S_HEX:
 554                 if (!sym_string_valid(sym, str))
 555                         return false;
 556                 prop = sym_get_range_prop(sym);
 557                 if (!prop)
 558                         return true;
 559                 val = strtol(str, NULL, 16);
 560                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 561                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 562         case S_BOOLEAN:
 563         case S_TRISTATE:
 564                 switch (str[0]) {
 565                 case 'y': case 'Y':
 566                         return sym_tristate_within_range(sym, yes);
 567                 case 'm': case 'M':
 568                         return sym_tristate_within_range(sym, mod);
 569                 case 'n': case 'N':
 570                         return sym_tristate_within_range(sym, no);
 571                 }
 572                 return false;
 573         default:
 574                 return false;
 575         }
 576 }
 577
 578 bool sym_set_string_value(struct symbol *sym, const char *newval)
 579 {
 580         const char *oldval;
 581         char *val;
 582         int size;
 583
 584         switch (sym->type) {
 585         case S_BOOLEAN:
 586         case S_TRISTATE:
 587                 switch (newval[0]) {
 588                 case 'y': case 'Y':
 589                         return sym_set_tristate_value(sym, yes);
 590                 case 'm': case 'M':
 591                         return sym_set_tristate_value(sym, mod);
 592                 case 'n': case 'N':
 593                         return sym_set_tristate_value(sym, no);
 594                 }
 595                 return false;
 596         default:
 597                 ;
 598         }
 599
 600         if (!sym_string_within_range(sym, newval))
 601                 return false;
 602
 603         if (sym->flags & SYMBOL_NEW) {
 604                 sym->flags &= ~SYMBOL_NEW;
 605                 sym_set_changed(sym);
 606         }
 607
 608         oldval = sym->user.val;
 609         size = strlen(newval) + 1;
 610         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 611                 size += 2;
 612                 sym->user.val = val = malloc(size);
 613                 *val++ = '0';
 614                 *val++ = 'x';
 615         } else if (!oldval || strcmp(oldval, newval))
 616                 sym->user.val = val = malloc(size);
 617         else
 618                 return true;
 619
 620         strcpy(val, newval);
 621         free((void *)oldval);
 622         sym_clear_all_valid();
 623
 624         return true;
 625 }
 626
 627 const char *sym_get_string_value(struct symbol *sym)
 628 {
 629         tristate val;
 630
 631         switch (sym->type) {
 632         case S_BOOLEAN:
 633         case S_TRISTATE:
 634                 val = sym_get_tristate_value(sym);
 635                 switch (val) {
 636                 case no:
 637                         return "n";
 638                 case mod:
 639                         return "m";
 640                 case yes:
 641                         return "y";
 642                 }
 643                 break;
 644         default:
 645                 ;
 646         }
 647         return (const char *)sym->curr.val;
 648 }
 649
 650 bool sym_is_changable(struct symbol *sym)
 651 {
 652         return sym->visible > sym->rev_dep.tri;
 653 }
 654
 655 struct symbol *sym_lookup(const char *name, int isconst)
 656 {
 657         struct symbol *symbol;
 658         const char *ptr;
 659         char *new_name;
 660         int hash = 0;
 661
 662         if (name) {
 663                 if (name[0] && !name[1]) {
 664                         switch (name[0]) {
 665                         case 'y': return &symbol_yes;
 666                         case 'm': return &symbol_mod;
 667                         case 'n': return &symbol_no;
 668                         }
 669                 }
 670                 for (ptr = name; *ptr; ptr++)
 671                         hash += *ptr;
 672                 hash &= 0xff;
 673
 674                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 675                         if (!strcmp(symbol->name, name)) {
 676                                 if ((isconst && symbol->flags & SYMBOL_CONST) ||
 677                                     (!isconst && !(symbol->flags & SYMBOL_CONST)))
 678                                         return symbol;
 679                         }
 680                 }
 681                 new_name = strdup(name);
 682         } else {
 683                 new_name = NULL;
 684                 hash = 256;
 685         }
 686
 687         symbol = malloc(sizeof(*symbol));
 688         memset(symbol, 0, sizeof(*symbol));
 689         symbol->name = new_name;
 690         symbol->type = S_UNKNOWN;
 691         symbol->flags = SYMBOL_NEW;
 692         if (isconst)
 693                 symbol->flags |= SYMBOL_CONST;
 694
 695         symbol->next = symbol_hash[hash];
 696         symbol_hash[hash] = symbol;
 697
 698         return symbol;
 699 }
 700
 701 struct symbol *sym_find(const char *name)
 702 {
 703         struct symbol *symbol = NULL;
 704         const char *ptr;
 705         int hash = 0;
 706
 707         if (!name)
 708                 return NULL;
 709
 710         if (name[0] && !name[1]) {
 711                 switch (name[0]) {
 712                 case 'y': return &symbol_yes;
 713                 case 'm': return &symbol_mod;
 714                 case 'n': return &symbol_no;
 715                 }
 716         }
 717         for (ptr = name; *ptr; ptr++)
 718                 hash += *ptr;
 719         hash &= 0xff;
 720
 721         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 722                 if (!strcmp(symbol->name, name) &&
 723                     !(symbol->flags & SYMBOL_CONST))
 724                                 break;
 725         }
 726
 727         return symbol;
 728 }
 729
 730 struct symbol **sym_re_search(const char *pattern)
 731 {
 732         struct symbol *sym, **sym_arr = NULL;
 733         int i, cnt, size;
 734         regex_t re;
 735
 736         cnt = size = 0;
 737         /* Skip if empty */
 738         if (strlen(pattern) == 0)
 739                 return NULL;
 740         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
 741                 return NULL;
 742
 743         for_all_symbols(i, sym) {
 744                 if (sym->flags & SYMBOL_CONST || !sym->name)
 745                         continue;
 746                 if (regexec(&re, sym->name, 0, NULL, 0))
 747                         continue;
 748                 if (cnt + 1 >= size) {
 749                         void *tmp = sym_arr;
 750                         size += 16;
 751                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
 752                         if (!sym_arr) {
 753                                 free(tmp);
 754                                 return NULL;
 755                         }
 756                 }
 757                 sym_arr[cnt++] = sym;
 758         }
 759         if (sym_arr)
 760                 sym_arr[cnt] = NULL;
 761         regfree(&re);
 762
 763         return sym_arr;
 764 }
 765
 766
 767 struct symbol *sym_check_deps(struct symbol *sym);
 768
 769 static struct symbol *sym_check_expr_deps(struct expr *e)
 770 {
 771         struct symbol *sym;
 772
 773         if (!e)
 774                 return NULL;
 775         switch (e->type) {
 776         case E_OR:
 777         case E_AND:
 778                 sym = sym_check_expr_deps(e->left.expr);
 779                 if (sym)
 780                         return sym;
 781                 return sym_check_expr_deps(e->right.expr);
 782         case E_NOT:
 783                 return sym_check_expr_deps(e->left.expr);
 784         case E_EQUAL:
 785         case E_UNEQUAL:
 786                 sym = sym_check_deps(e->left.sym);
 787                 if (sym)
 788                         return sym;
 789                 return sym_check_deps(e->right.sym);
 790         case E_SYMBOL:
 791                 return sym_check_deps(e->left.sym);
 792         default:
 793                 break;
 794         }
 795         printf("Oops! How to check %d?\n", e->type);
 796         return NULL;
 797 }
 798
 799 struct symbol *sym_check_deps(struct symbol *sym)
 800 {
 801         struct symbol *sym2;
 802         struct property *prop;
 803
 804         if (sym->flags & SYMBOL_CHECK) {
 805                 printf("Warning! Found recursive dependency: %s", sym->name);
 806                 return sym;
 807         }
 808         if (sym->flags & SYMBOL_CHECKED)
 809                 return NULL;
 810
 811         sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
 812         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
 813         if (sym2)
 814                 goto out;
 815
 816         for (prop = sym->prop; prop; prop = prop->next) {
 817                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
 818                         continue;
 819                 sym2 = sym_check_expr_deps(prop->visible.expr);
 820                 if (sym2)
 821                         goto out;
 822                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
 823                         continue;
 824                 sym2 = sym_check_expr_deps(prop->expr);
 825                 if (sym2)
 826                         goto out;
 827         }
 828 out:
 829         if (sym2) {
 830                 printf(" %s", sym->name);
 831                 if (sym2 == sym) {
 832                         printf("\n");
 833                         sym2 = NULL;
 834                 }
 835         }
 836         sym->flags &= ~SYMBOL_CHECK;
 837         return sym2;
 838 }
 839
 840 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
 841 {
 842         struct property *prop;
 843         struct property **propp;
 844
 845         prop = malloc(sizeof(*prop));
 846         memset(prop, 0, sizeof(*prop));
 847         prop->type = type;
 848         prop->sym = sym;
 849         prop->file = current_file;
 850         prop->lineno = zconf_lineno();
 851
 852         /* append property to the prop list of symbol */
 853         if (sym) {
 854                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
 855                         ;
 856                 *propp = prop;
 857         }
 858
 859         return prop;
 860 }
 861
 862 struct symbol *prop_get_symbol(struct property *prop)
 863 {
 864         if (prop->expr && (prop->expr->type == E_SYMBOL ||
 865                            prop->expr->type == E_CHOICE))
 866                 return prop->expr->left.sym;
 867         return NULL;
 868 }
 869
 870 const char *prop_get_type_name(enum prop_type type)
 871 {
 872         switch (type) {
 873         case P_PROMPT:
 874                 return "prompt";
 875         case P_COMMENT:
 876                 return "comment";
 877         case P_MENU:
 878                 return "menu";
 879         case P_DEFAULT:
 880                 return "default";
 881         case P_CHOICE:
 882                 return "choice";
 883         case P_SELECT:
 884                 return "select";
 885         case P_RANGE:
 886                 return "range";
 887         case P_UNKNOWN:
 888                 break;
 889         }
 890         return "unknown";
 891 }