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         if (tri == mod && (sym->type != S_TRISTATE))
 208                 tri = yes;
 209         if (sym->rev_dep_inv.expr) {
 210                 if (expr_calc_value(sym->rev_dep_inv.expr) == yes)
 211                         tri = no;
 212         }
 213         if (sym->visible != tri) {
 214                 sym->visible = tri;
 215                 sym_set_changed(sym);
 216         }
 217         if (sym_is_choice_value(sym))
 218                 return;
 219         tri = no;
 220         if (sym->rev_dep.expr)
 221                 tri = expr_calc_value(sym->rev_dep.expr);
 222         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 223                 tri = yes;
 224         if (sym->rev_dep.tri != tri) {
 225                 sym->rev_dep.tri = tri;
 226                 sym_set_changed(sym);
 227         }
 228 }
 229
 230 static struct symbol *sym_calc_choice(struct symbol *sym)
 231 {
 232         struct symbol *def_sym;
 233         struct property *prop;
 234         struct expr *e;
 235
 236         /* is the user choice visible? */
 237         def_sym = sym->user.val;
 238         if (def_sym) {
 239                 sym_calc_visibility(def_sym);
 240                 if (def_sym->visible != no)
 241                         return def_sym;
 242         }
 243
 244         /* any of the defaults visible? */
 245         for_all_defaults(sym, prop) {
 246                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 247                 if (prop->visible.tri == no)
 248                         continue;
 249                 def_sym = prop_get_symbol(prop);
 250                 sym_calc_visibility(def_sym);
 251                 if (def_sym->visible != no)
 252                         return def_sym;
 253         }
 254
 255         /* just get the first visible value */
 256         prop = sym_get_choice_prop(sym);
 257         for (e = prop->expr; e; e = e->left.expr) {
 258                 def_sym = e->right.sym;
 259                 sym_calc_visibility(def_sym);
 260                 if (def_sym->visible != no)
 261                         return def_sym;
 262         }
 263
 264         /* no choice? reset tristate value */
 265         sym->curr.tri = no;
 266         return NULL;
 267 }
 268
 269 void sym_calc_value(struct symbol *sym)
 270 {
 271         struct symbol_value newval, oldval;
 272         struct property *prop;
 273         struct expr *e;
 274
 275         if (!sym)
 276                 return;
 277
 278         if (sym->flags & SYMBOL_VALID)
 279                 return;
 280         sym->flags |= SYMBOL_VALID;
 281
 282         oldval = sym->curr;
 283
 284         switch (sym->type) {
 285         case S_INT:
 286         case S_HEX:
 287         case S_STRING:
 288                 newval = symbol_empty.curr;
 289                 break;
 290         case S_BOOLEAN:
 291         case S_TRISTATE:
 292                 newval = symbol_no.curr;
 293                 break;
 294         default:
 295                 sym->curr.val = sym->name;
 296                 sym->curr.tri = no;
 297                 return;
 298         }
 299         if (!sym_is_choice_value(sym))
 300                 sym->flags &= ~SYMBOL_WRITE;
 301
 302         sym_calc_visibility(sym);
 303
 304         /* set default if recursively called */
 305         sym->curr = newval;
 306
 307         switch (sym_get_type(sym)) {
 308         case S_BOOLEAN:
 309         case S_TRISTATE:
 310                 if (sym_is_choice_value(sym) && sym->visible == yes) {
 311                         prop = sym_get_choice_prop(sym);
 312                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 313                 } else if (E_OR(sym->visible, sym->rev_dep.tri) != no) {
 314                         sym->flags |= SYMBOL_WRITE;
 315                         if (sym_has_value(sym))
 316                                 newval.tri = sym->user.tri;
 317                         else if (!sym_is_choice(sym)) {
 318                                 prop = sym_get_default_prop(sym);
 319                                 if (prop)
 320                                         newval.tri = expr_calc_value(prop->expr);
 321                         }
 322                         newval.tri = E_OR(E_AND(newval.tri, sym->visible), sym->rev_dep.tri);
 323                 } else if (!sym_is_choice(sym)) {
 324                         prop = sym_get_default_prop(sym);
 325                         if (prop) {
 326                                 sym->flags |= SYMBOL_WRITE;
 327                                 newval.tri = expr_calc_value(prop->expr);
 328                         }
 329                 }
 330                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 331                         newval.tri = yes;
 332                 break;
 333         case S_STRING:
 334         case S_HEX:
 335         case S_INT:
 336                 if (sym->visible != no) {
 337                         sym->flags |= SYMBOL_WRITE;
 338                         if (sym_has_value(sym)) {
 339                                 newval.val = sym->user.val;
 340                                 break;
 341                         }
 342                 }
 343                 prop = sym_get_default_prop(sym);
 344                 if (prop) {
 345                         struct symbol *ds = prop_get_symbol(prop);
 346                         if (ds) {
 347                                 sym->flags |= SYMBOL_WRITE;
 348                                 sym_calc_value(ds);
 349                                 newval.val = ds->curr.val;
 350                         }
 351                 }
 352                 break;
 353         default:
 354                 ;
 355         }
 356
 357         sym->curr = newval;
 358         if (sym_is_choice(sym) && newval.tri == yes)
 359                 sym->curr.val = sym_calc_choice(sym);
 360         sym_validate_range(sym);
 361
 362         if (memcmp(&oldval, &sym->curr, sizeof(oldval)))
 363                 sym_set_changed(sym);
 364
 365         if (modules_sym == sym)
 366                 modules_val = modules_sym->curr.tri;
 367
 368         if (sym_is_choice(sym)) {
 369                 int flags = sym->flags & (SYMBOL_CHANGED | SYMBOL_WRITE);
 370                 prop = sym_get_choice_prop(sym);
 371                 for (e = prop->expr; e; e = e->left.expr) {
 372                         e->right.sym->flags |= flags;
 373                         if (flags & SYMBOL_CHANGED)
 374                                 sym_set_changed(e->right.sym);
 375                 }
 376         }
 377 }
 378
 379 void sym_clear_all_valid(void)
 380 {
 381         struct symbol *sym;
 382         int i;
 383
 384         for_all_symbols(i, sym)
 385                 sym->flags &= ~SYMBOL_VALID;
 386         sym_change_count++;
 387         if (modules_sym)
 388                 sym_calc_value(modules_sym);
 389 }
 390
 391 void sym_set_changed(struct symbol *sym)
 392 {
 393         struct property *prop;
 394
 395         sym->flags |= SYMBOL_CHANGED;
 396         for (prop = sym->prop; prop; prop = prop->next) {
 397                 if (prop->menu)
 398                         prop->menu->flags |= MENU_CHANGED;
 399         }
 400 }
 401
 402 void sym_set_all_changed(void)
 403 {
 404         struct symbol *sym;
 405         int i;
 406
 407         for_all_symbols(i, sym)
 408                 sym_set_changed(sym);
 409 }
 410
 411 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 412 {
 413         int type = sym_get_type(sym);
 414
 415         if (sym->visible == no)
 416                 return false;
 417
 418         if (type != S_BOOLEAN && type != S_TRISTATE)
 419                 return false;
 420
 421         if (type == S_BOOLEAN && val == mod)
 422                 return false;
 423         if (sym->visible <= sym->rev_dep.tri)
 424                 return false;
 425         if (sym_is_choice_value(sym) && sym->visible == yes)
 426                 return val == yes;
 427         return val >= sym->rev_dep.tri && val <= sym->visible;
 428 }
 429
 430 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 431 {
 432         tristate oldval = sym_get_tristate_value(sym);
 433
 434         if (oldval != val && !sym_tristate_within_range(sym, val))
 435                 return false;
 436
 437         if (sym->flags & SYMBOL_NEW) {
 438                 sym->flags &= ~SYMBOL_NEW;
 439                 sym_set_changed(sym);
 440         }
 441         /*
 442          * setting a choice value also resets the new flag of the choice
 443          * symbol and all other choice values.
 444          */
 445         if (sym_is_choice_value(sym) && val == yes) {
 446                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 447                 struct property *prop;
 448                 struct expr *e;
 449
 450                 cs->user.val = sym;
 451                 cs->flags &= ~SYMBOL_NEW;
 452                 prop = sym_get_choice_prop(cs);
 453                 for (e = prop->expr; e; e = e->left.expr) {
 454                         if (e->right.sym->visible != no)
 455                                 e->right.sym->flags &= ~SYMBOL_NEW;
 456                 }
 457         }
 458
 459         sym->user.tri = val;
 460         if (oldval != val) {
 461                 sym_clear_all_valid();
 462                 if (sym == modules_sym)
 463                         sym_set_all_changed();
 464         }
 465
 466         return true;
 467 }
 468
 469 tristate sym_toggle_tristate_value(struct symbol *sym)
 470 {
 471         tristate oldval, newval;
 472
 473         oldval = newval = sym_get_tristate_value(sym);
 474         do {
 475                 switch (newval) {
 476                 case no:
 477                         newval = mod;
 478                         break;
 479                 case mod:
 480                         newval = yes;
 481                         break;
 482                 case yes:
 483                         newval = no;
 484                         break;
 485                 }
 486                 if (sym_set_tristate_value(sym, newval))
 487                         break;
 488         } while (oldval != newval);
 489         return newval;
 490 }
 491
 492 bool sym_string_valid(struct symbol *sym, const char *str)
 493 {
 494         signed char ch;
 495
 496         switch (sym->type) {
 497         case S_STRING:
 498                 return true;
 499         case S_INT:
 500                 ch = *str++;
 501                 if (ch == '-')
 502                         ch = *str++;
 503                 if (!isdigit(ch))
 504                         return false;
 505                 if (ch == '0' && *str != 0)
 506                         return false;
 507                 while ((ch = *str++)) {
 508                         if (!isdigit(ch))
 509                                 return false;
 510                 }
 511                 return true;
 512         case S_HEX:
 513                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 514                         str += 2;
 515                 ch = *str++;
 516                 do {
 517                         if (!isxdigit(ch))
 518                                 return false;
 519                 } while ((ch = *str++));
 520                 return true;
 521         case S_BOOLEAN:
 522         case S_TRISTATE:
 523                 switch (str[0]) {
 524                 case 'y': case 'Y':
 525                 case 'm': case 'M':
 526                 case 'n': case 'N':
 527                         return true;
 528                 }
 529                 return false;
 530         default:
 531                 return false;
 532         }
 533 }
 534
 535 bool sym_string_within_range(struct symbol *sym, const char *str)
 536 {
 537         struct property *prop;
 538         int val;
 539
 540         switch (sym->type) {
 541         case S_STRING:
 542                 return sym_string_valid(sym, str);
 543         case S_INT:
 544                 if (!sym_string_valid(sym, str))
 545                         return false;
 546                 prop = sym_get_range_prop(sym);
 547                 if (!prop)
 548                         return true;
 549                 val = strtol(str, NULL, 10);
 550                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 551                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 552         case S_HEX:
 553                 if (!sym_string_valid(sym, str))
 554                         return false;
 555                 prop = sym_get_range_prop(sym);
 556                 if (!prop)
 557                         return true;
 558                 val = strtol(str, NULL, 16);
 559                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 560                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 561         case S_BOOLEAN:
 562         case S_TRISTATE:
 563                 switch (str[0]) {
 564                 case 'y': case 'Y':
 565                         return sym_tristate_within_range(sym, yes);
 566                 case 'm': case 'M':
 567                         return sym_tristate_within_range(sym, mod);
 568                 case 'n': case 'N':
 569                         return sym_tristate_within_range(sym, no);
 570                 }
 571                 return false;
 572         default:
 573                 return false;
 574         }
 575 }
 576
 577 bool sym_set_string_value(struct symbol *sym, const char *newval)
 578 {
 579         const char *oldval;
 580         char *val;
 581         int size;
 582
 583         switch (sym->type) {
 584         case S_BOOLEAN:
 585         case S_TRISTATE:
 586                 switch (newval[0]) {
 587                 case 'y': case 'Y':
 588                         return sym_set_tristate_value(sym, yes);
 589                 case 'm': case 'M':
 590                         return sym_set_tristate_value(sym, mod);
 591                 case 'n': case 'N':
 592                         return sym_set_tristate_value(sym, no);
 593                 }
 594                 return false;
 595         default:
 596                 ;
 597         }
 598
 599         if (!sym_string_within_range(sym, newval))
 600                 return false;
 601
 602         if (sym->flags & SYMBOL_NEW) {
 603                 sym->flags &= ~SYMBOL_NEW;
 604                 sym_set_changed(sym);
 605         }
 606
 607         oldval = sym->user.val;
 608         size = strlen(newval) + 1;
 609         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 610                 size += 2;
 611                 sym->user.val = val = malloc(size);
 612                 *val++ = '0';
 613                 *val++ = 'x';
 614         } else if (!oldval || strcmp(oldval, newval))
 615                 sym->user.val = val = malloc(size);
 616         else
 617                 return true;
 618
 619         strcpy(val, newval);
 620         free((void *)oldval);
 621         sym_clear_all_valid();
 622
 623         return true;
 624 }
 625
 626 const char *sym_get_string_value(struct symbol *sym)
 627 {
 628         tristate val;
 629
 630         switch (sym->type) {
 631         case S_BOOLEAN:
 632         case S_TRISTATE:
 633                 val = sym_get_tristate_value(sym);
 634                 switch (val) {
 635                 case no:
 636                         return "n";
 637                 case mod:
 638                         return "m";
 639                 case yes:
 640                         return "y";
 641                 }
 642                 break;
 643         default:
 644                 ;
 645         }
 646         return (const char *)sym->curr.val;
 647 }
 648
 649 bool sym_is_changable(struct symbol *sym)
 650 {
 651         return sym->visible > sym->rev_dep.tri;
 652 }
 653
 654 struct symbol *sym_lookup(const char *name, int isconst)
 655 {
 656         struct symbol *symbol;
 657         const char *ptr;
 658         char *new_name;
 659         int hash = 0;
 660
 661         if (name) {
 662                 if (name[0] && !name[1]) {
 663                         switch (name[0]) {
 664                         case 'y': return &symbol_yes;
 665                         case 'm': return &symbol_mod;
 666                         case 'n': return &symbol_no;
 667                         }
 668                 }
 669                 for (ptr = name; *ptr; ptr++)
 670                         hash += *ptr;
 671                 hash &= 0xff;
 672
 673                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 674                         if (!strcmp(symbol->name, name)) {
 675                                 if ((isconst && symbol->flags & SYMBOL_CONST) ||
 676                                     (!isconst && !(symbol->flags & SYMBOL_CONST)))
 677                                         return symbol;
 678                         }
 679                 }
 680                 new_name = strdup(name);
 681         } else {
 682                 new_name = NULL;
 683                 hash = 256;
 684         }
 685
 686         symbol = malloc(sizeof(*symbol));
 687         memset(symbol, 0, sizeof(*symbol));
 688         symbol->name = new_name;
 689         symbol->type = S_UNKNOWN;
 690         symbol->flags = SYMBOL_NEW;
 691         if (isconst)
 692                 symbol->flags |= SYMBOL_CONST;
 693
 694         symbol->next = symbol_hash[hash];
 695         symbol_hash[hash] = symbol;
 696
 697         return symbol;
 698 }
 699
 700 struct symbol *sym_find(const char *name)
 701 {
 702         struct symbol *symbol = NULL;
 703         const char *ptr;
 704         int hash = 0;
 705
 706         if (!name)
 707                 return NULL;
 708
 709         if (name[0] && !name[1]) {
 710                 switch (name[0]) {
 711                 case 'y': return &symbol_yes;
 712                 case 'm': return &symbol_mod;
 713                 case 'n': return &symbol_no;
 714                 }
 715         }
 716         for (ptr = name; *ptr; ptr++)
 717                 hash += *ptr;
 718         hash &= 0xff;
 719
 720         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 721                 if (!strcmp(symbol->name, name) &&
 722                     !(symbol->flags & SYMBOL_CONST))
 723                                 break;
 724         }
 725
 726         return symbol;
 727 }
 728
 729 struct symbol **sym_re_search(const char *pattern)
 730 {
 731         struct symbol *sym, **sym_arr = NULL;
 732         int i, cnt, size;
 733         regex_t re;
 734
 735         cnt = size = 0;
 736         /* Skip if empty */
 737         if (strlen(pattern) == 0)
 738                 return NULL;
 739         if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
 740                 return NULL;
 741
 742         for_all_symbols(i, sym) {
 743                 if (sym->flags & SYMBOL_CONST || !sym->name)
 744                         continue;
 745                 if (regexec(&re, sym->name, 0, NULL, 0))
 746                         continue;
 747                 if (cnt + 1 >= size) {
 748                         void *tmp = sym_arr;
 749                         size += 16;
 750                         sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
 751                         if (!sym_arr) {
 752                                 free(tmp);
 753                                 return NULL;
 754                         }
 755                 }
 756                 sym_arr[cnt++] = sym;
 757         }
 758         if (sym_arr)
 759                 sym_arr[cnt] = NULL;
 760         regfree(&re);
 761
 762         return sym_arr;
 763 }
 764
 765
 766 struct symbol *sym_check_deps(struct symbol *sym);
 767
 768 static struct symbol *sym_check_expr_deps(struct expr *e)
 769 {
 770         struct symbol *sym;
 771
 772         if (!e)
 773                 return NULL;
 774         switch (e->type) {
 775         case E_OR:
 776         case E_AND:
 777                 sym = sym_check_expr_deps(e->left.expr);
 778                 if (sym)
 779                         return sym;
 780                 return sym_check_expr_deps(e->right.expr);
 781         case E_NOT:
 782                 return sym_check_expr_deps(e->left.expr);
 783         case E_EQUAL:
 784         case E_UNEQUAL:
 785                 sym = sym_check_deps(e->left.sym);
 786                 if (sym)
 787                         return sym;
 788                 return sym_check_deps(e->right.sym);
 789         case E_SYMBOL:
 790                 return sym_check_deps(e->left.sym);
 791         default:
 792                 break;
 793         }
 794         printf("Oops! How to check %d?\n", e->type);
 795         return NULL;
 796 }
 797
 798 struct symbol *sym_check_deps(struct symbol *sym)
 799 {
 800         struct symbol *sym2;
 801         struct property *prop;
 802
 803         if (sym->flags & SYMBOL_CHECK) {
 804                 printf("Warning! Found recursive dependency: %s", sym->name);
 805                 return sym;
 806         }
 807         if (sym->flags & SYMBOL_CHECKED)
 808                 return NULL;
 809
 810         sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
 811         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
 812         if (sym2)
 813                 goto out;
 814
 815         for (prop = sym->prop; prop; prop = prop->next) {
 816                 if (prop->type == P_CHOICE || prop->type == P_SELECT || prop->type == P_DESELECT)
 817                         continue;
 818                 sym2 = sym_check_expr_deps(prop->visible.expr);
 819                 if (sym2)
 820                         goto out;
 821                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
 822                         continue;
 823                 sym2 = sym_check_expr_deps(prop->expr);
 824                 if (sym2)
 825                         goto out;
 826         }
 827 out:
 828         if (sym2) {
 829                 printf(" %s", sym->name);
 830                 if (sym2 == sym) {
 831                         printf("\n");
 832                         sym2 = NULL;
 833                 }
 834         }
 835         sym->flags &= ~SYMBOL_CHECK;
 836         return sym2;
 837 }
 838
 839 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
 840 {
 841         struct property *prop;
 842         struct property **propp;
 843
 844         prop = malloc(sizeof(*prop));
 845         memset(prop, 0, sizeof(*prop));
 846         prop->type = type;
 847         prop->sym = sym;
 848         prop->file = current_file;
 849         prop->lineno = zconf_lineno();
 850
 851         /* append property to the prop list of symbol */
 852         if (sym) {
 853                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
 854                         ;
 855                 *propp = prop;
 856         }
 857
 858         return prop;
 859 }
 860
 861 struct symbol *prop_get_symbol(struct property *prop)
 862 {
 863         if (prop->expr && (prop->expr->type == E_SYMBOL ||
 864                            prop->expr->type == E_CHOICE))
 865                 return prop->expr->left.sym;
 866         return NULL;
 867 }
 868
 869 const char *prop_get_type_name(enum prop_type type)
 870 {
 871         switch (type) {
 872         case P_PROMPT:
 873                 return "prompt";
 874         case P_COMMENT:
 875                 return "comment";
 876         case P_MENU:
 877                 return "menu";
 878         case P_DEFAULT:
 879                 return "default";
 880         case P_CHOICE:
 881                 return "choice";
 882         case P_SELECT:
 883                 return "select";
 884         case P_DESELECT:
 885                 return "deselect";
 886         case P_RANGE:
 887                 return "range";
 888         case P_UNKNOWN:
 889                 break;
 890         }
 891         return "unknown";
 892 }