util/kconfig/symbol.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   4  */
   5
   6 #include <sys/types.h>
   7 #include <ctype.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <regex.h>
  11
  12 #include "lkc.h"
  13
  14 struct symbol symbol_yes = {
  15         .name = "y",
  16         .curr = { "y", yes },
  17         .flags = SYMBOL_CONST|SYMBOL_VALID,
  18 };
  19
  20 struct symbol symbol_mod = {
  21         .name = "m",
  22         .curr = { "m", mod },
  23         .flags = SYMBOL_CONST|SYMBOL_VALID,
  24 };
  25
  26 struct symbol symbol_no = {
  27         .name = "n",
  28         .curr = { "n", no },
  29         .flags = SYMBOL_CONST|SYMBOL_VALID,
  30 };
  31
  32 struct symbol *modules_sym;
  33 static tristate modules_val;
  34 static int sym_warnings;
  35
  36 enum symbol_type sym_get_type(struct symbol *sym)
  37 {
  38         enum symbol_type type = sym->type;
  39
  40         if (type == S_TRISTATE) {
  41                 if (sym_is_choice_value(sym) && sym->visible == yes)
  42                         type = S_BOOLEAN;
  43                 else if (modules_val == no)
  44                         type = S_BOOLEAN;
  45         }
  46         return type;
  47 }
  48
  49 const char *sym_type_name(enum symbol_type type)
  50 {
  51         switch (type) {
  52         case S_BOOLEAN:
  53                 return "bool";
  54         case S_TRISTATE:
  55                 return "tristate";
  56         case S_INT:
  57                 return "integer";
  58         case S_HEX:
  59                 return "hex";
  60         case S_STRING:
  61                 return "string";
  62         case S_UNKNOWN:
  63                 return "unknown";
  64         }
  65         return "???";
  66 }
  67
  68 struct property *sym_get_choice_prop(struct symbol *sym)
  69 {
  70         struct property *prop;
  71
  72         for_all_choices(sym, prop)
  73                 return prop;
  74         return NULL;
  75 }
  76
  77 static struct property *sym_get_default_prop(struct symbol *sym)
  78 {
  79         struct property *prop;
  80
  81         for_all_defaults(sym, prop) {
  82                 prop->visible.tri = expr_calc_value(prop->visible.expr);
  83                 if (prop->visible.tri != no)
  84                         return prop;
  85         }
  86         return NULL;
  87 }
  88
  89 struct property *sym_get_range_prop(struct symbol *sym)
  90 {
  91         struct property *prop;
  92
  93         for_all_properties(sym, prop, P_RANGE) {
  94                 prop->visible.tri = expr_calc_value(prop->visible.expr);
  95                 if (prop->visible.tri != no)
  96                         return prop;
  97         }
  98         return NULL;
  99 }
 100
 101 static long long sym_get_range_val(struct symbol *sym, int base)
 102 {
 103         sym_calc_value(sym);
 104         switch (sym->type) {
 105         case S_INT:
 106                 base = 10;
 107                 break;
 108         case S_HEX:
 109                 base = 16;
 110                 break;
 111         default:
 112                 break;
 113         }
 114         return strtoll(sym->curr.val, NULL, base);
 115 }
 116
 117 static void sym_validate_range(struct symbol *sym)
 118 {
 119         struct property *prop;
 120         struct symbol *range_sym;
 121         int base;
 122         long long val, val2;
 123
 124         switch (sym->type) {
 125         case S_INT:
 126                 base = 10;
 127                 break;
 128         case S_HEX:
 129                 base = 16;
 130                 break;
 131         default:
 132                 return;
 133         }
 134         prop = sym_get_range_prop(sym);
 135         if (!prop)
 136                 return;
 137         val = strtoll(sym->curr.val, NULL, base);
 138         range_sym = prop->expr->left.sym;
 139         val2 = sym_get_range_val(range_sym, base);
 140         if (val >= val2) {
 141                 range_sym = prop->expr->right.sym;
 142                 val2 = sym_get_range_val(range_sym, base);
 143                 if (val <= val2)
 144                         return;
 145         }
 146         sym->curr.val = range_sym->curr.val;
 147 }
 148
 149 static void sym_set_changed(struct symbol *sym)
 150 {
 151         struct property *prop;
 152
 153         sym->flags |= SYMBOL_CHANGED;
 154         for (prop = sym->prop; prop; prop = prop->next) {
 155                 if (prop->menu)
 156                         prop->menu->flags |= MENU_CHANGED;
 157         }
 158 }
 159
 160 static void sym_set_all_changed(void)
 161 {
 162         struct symbol *sym;
 163         int i;
 164
 165         for_all_symbols(i, sym)
 166                 sym_set_changed(sym);
 167 }
 168
 169 static void sym_calc_visibility(struct symbol *sym)
 170 {
 171         struct property *prop;
 172         struct symbol *choice_sym = NULL;
 173         tristate tri;
 174
 175         /* any prompt visible? */
 176         tri = no;
 177
 178         if (sym_is_choice_value(sym))
 179                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 180
 181         for_all_prompts(sym, prop) {
 182                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 183                 /*
 184                  * Tristate choice_values with visibility 'mod' are
 185                  * not visible if the corresponding choice's value is
 186                  * 'yes'.
 187                  */
 188                 if (choice_sym && sym->type == S_TRISTATE &&
 189                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
 190                         prop->visible.tri = no;
 191
 192                 tri = EXPR_OR(tri, prop->visible.tri);
 193         }
 194         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 195                 tri = yes;
 196         if (sym->visible != tri) {
 197                 sym->visible = tri;
 198                 sym_set_changed(sym);
 199         }
 200         if (sym_is_choice_value(sym))
 201                 return;
 202         /* defaulting to "yes" if no explicit "depends on" are given */
 203         tri = yes;
 204         if (sym->dir_dep.expr)
 205                 tri = expr_calc_value(sym->dir_dep.expr);
 206         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 207                 tri = yes;
 208         if (sym->dir_dep.tri != tri) {
 209                 sym->dir_dep.tri = tri;
 210                 sym_set_changed(sym);
 211         }
 212         tri = no;
 213         if (sym->rev_dep.expr)
 214                 tri = expr_calc_value(sym->rev_dep.expr);
 215         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 216                 tri = yes;
 217         if (sym->rev_dep.tri != tri) {
 218                 sym->rev_dep.tri = tri;
 219                 sym_set_changed(sym);
 220         }
 221         tri = no;
 222         if (sym->implied.expr)
 223                 tri = expr_calc_value(sym->implied.expr);
 224         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 225                 tri = yes;
 226         if (sym->implied.tri != tri) {
 227                 sym->implied.tri = tri;
 228                 sym_set_changed(sym);
 229         }
 230 }
 231
 232 /*
 233  * Find the default symbol for a choice.
 234  * First try the default values for the choice symbol
 235  * Next locate the first visible choice value
 236  * Return NULL if none was found
 237  */
 238 struct symbol *sym_choice_default(struct symbol *sym)
 239 {
 240         struct symbol *def_sym;
 241         struct property *prop;
 242         struct expr *e;
 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                 if (def_sym->visible != no)
 251                         return def_sym;
 252         }
 253
 254         /* just get the first visible value */
 255         prop = sym_get_choice_prop(sym);
 256         expr_list_for_each_sym(prop->expr, e, def_sym)
 257                 if (def_sym->visible != no)
 258                         return def_sym;
 259
 260         /* failed to locate any defaults */
 261         return NULL;
 262 }
 263
 264 static struct symbol *sym_calc_choice(struct symbol *sym)
 265 {
 266         struct symbol *def_sym;
 267         struct property *prop;
 268         struct expr *e;
 269         int flags;
 270
 271         /* first calculate all choice values' visibilities */
 272         flags = sym->flags;
 273         prop = sym_get_choice_prop(sym);
 274         expr_list_for_each_sym(prop->expr, e, def_sym) {
 275                 sym_calc_visibility(def_sym);
 276                 if (def_sym->visible != no)
 277                         flags &= def_sym->flags;
 278         }
 279
 280         sym->flags &= flags | ~SYMBOL_DEF_USER;
 281
 282         /* is the user choice visible? */
 283         def_sym = sym->def[S_DEF_USER].val;
 284         if (def_sym && def_sym->visible != no)
 285                 return def_sym;
 286
 287         def_sym = sym_choice_default(sym);
 288
 289         if (def_sym == NULL)
 290                 /* no choice? reset tristate value */
 291                 sym->curr.tri = no;
 292
 293         return def_sym;
 294 }
 295
 296 static void sym_warn_unmet_dep(struct symbol *sym)
 297 {
 298         struct gstr gs = str_new();
 299
 300         str_printf(&gs,
 301                    "\nWARNING: unmet direct dependencies detected for %s\n",
 302                    sym->name);
 303         str_printf(&gs,
 304                    "  Depends on [%c]: ",
 305                    sym->dir_dep.tri == mod ? 'm' : 'n');
 306         expr_gstr_print(sym->dir_dep.expr, &gs);
 307         str_printf(&gs, "\n");
 308
 309         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 310                                "  Selected by [y]:\n");
 311         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 312                                "  Selected by [m]:\n");
 313
 314         fputs(str_get(&gs), stderr);
 315         sym_warnings++;
 316 }
 317
 318 bool sym_dep_errors(void)
 319 {
 320         if (sym_warnings)
 321                 return getenv("KCONFIG_WERROR");
 322         return false;
 323 }
 324
 325 void sym_calc_value(struct symbol *sym)
 326 {
 327         struct symbol_value newval, oldval;
 328         struct property *prop;
 329         struct expr *e;
 330
 331         if (!sym)
 332                 return;
 333
 334         if (sym->flags & SYMBOL_VALID)
 335                 return;
 336
 337         if (sym_is_choice_value(sym) &&
 338             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 339                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 340                 prop = sym_get_choice_prop(sym);
 341                 sym_calc_value(prop_get_symbol(prop));
 342         }
 343
 344         sym->flags |= SYMBOL_VALID;
 345
 346         oldval = sym->curr;
 347
 348         newval.tri = no;
 349
 350         switch (sym->type) {
 351         case S_INT:
 352                 newval.val = "0";
 353                 break;
 354         case S_HEX:
 355                 newval.val = "0x0";
 356                 break;
 357         case S_STRING:
 358                 newval.val = "";
 359                 break;
 360         case S_BOOLEAN:
 361         case S_TRISTATE:
 362                 newval.val = "n";
 363                 break;
 364         default:
 365                 sym->curr.val = sym->name;
 366                 sym->curr.tri = no;
 367                 return;
 368         }
 369         sym->flags &= ~SYMBOL_WRITE;
 370
 371         sym_calc_visibility(sym);
 372
 373         if (sym->visible != no)
 374                 sym->flags |= SYMBOL_WRITE;
 375
 376         /* set default if recursively called */
 377         sym->curr = newval;
 378
 379         switch (sym_get_type(sym)) {
 380         case S_BOOLEAN:
 381         case S_TRISTATE:
 382                 if (sym_is_choice_value(sym) && sym->visible == yes) {
 383                         prop = sym_get_choice_prop(sym);
 384                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 385                 } else {
 386                         if (sym->visible != no) {
 387                                 /* if the symbol is visible use the user value
 388                                  * if available, otherwise try the default value
 389                                  */
 390                                 if (sym_has_value(sym)) {
 391                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 392                                                               sym->visible);
 393                                         goto calc_newval;
 394                                 }
 395                         }
 396                         if (sym->rev_dep.tri != no)
 397                                 sym->flags |= SYMBOL_WRITE;
 398                         if (!sym_is_choice(sym)) {
 399                                 prop = sym_get_default_prop(sym);
 400                                 if (prop) {
 401                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 402                                                               prop->visible.tri);
 403                                         if (newval.tri != no)
 404                                                 sym->flags |= SYMBOL_WRITE;
 405                                 }
 406                                 if (sym->implied.tri != no) {
 407                                         sym->flags |= SYMBOL_WRITE;
 408                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 409                                         newval.tri = EXPR_AND(newval.tri,
 410                                                               sym->dir_dep.tri);
 411                                 }
 412                         }
 413                 calc_newval:
 414                         if (sym->dir_dep.tri < sym->rev_dep.tri)
 415                                 sym_warn_unmet_dep(sym);
 416                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 417                 }
 418                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 419                         newval.tri = yes;
 420                 break;
 421         case S_STRING:
 422         case S_HEX:
 423         case S_INT:
 424                 if (sym->visible != no && sym_has_value(sym)) {
 425                         newval.val = sym->def[S_DEF_USER].val;
 426                         break;
 427                 }
 428                 prop = sym_get_default_prop(sym);
 429                 if (prop) {
 430                         struct symbol *ds = prop_get_symbol(prop);
 431                         if (ds) {
 432                                 sym->flags |= SYMBOL_WRITE;
 433                                 sym_calc_value(ds);
 434                                 newval.val = ds->curr.val;
 435                         }
 436                 }
 437                 break;
 438         default:
 439                 ;
 440         }
 441
 442         sym->curr = newval;
 443         if (sym_is_choice(sym) && newval.tri == yes)
 444                 sym->curr.val = sym_calc_choice(sym);
 445         sym_validate_range(sym);
 446
 447         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 448                 sym_set_changed(sym);
 449                 if (modules_sym == sym) {
 450                         sym_set_all_changed();
 451                         modules_val = modules_sym->curr.tri;
 452                 }
 453         }
 454
 455         if (sym_is_choice(sym)) {
 456                 struct symbol *choice_sym;
 457
 458                 prop = sym_get_choice_prop(sym);
 459                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
 460                         if ((sym->flags & SYMBOL_WRITE) &&
 461                             choice_sym->visible != no)
 462                                 choice_sym->flags |= SYMBOL_WRITE;
 463                         if (sym->flags & SYMBOL_CHANGED)
 464                                 sym_set_changed(choice_sym);
 465                 }
 466         }
 467
 468         if (sym->flags & SYMBOL_NO_WRITE)
 469                 sym->flags &= ~SYMBOL_WRITE;
 470
 471         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 472                 set_all_choice_values(sym);
 473 }
 474
 475 void sym_clear_all_valid(void)
 476 {
 477         struct symbol *sym;
 478         int i;
 479
 480         for_all_symbols(i, sym)
 481                 sym->flags &= ~SYMBOL_VALID;
 482         conf_set_changed(true);
 483         sym_calc_value(modules_sym);
 484 }
 485
 486 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 487 {
 488         int type = sym_get_type(sym);
 489
 490         if (sym->visible == no)
 491                 return false;
 492
 493         if (type != S_BOOLEAN && type != S_TRISTATE)
 494                 return false;
 495
 496         if (type == S_BOOLEAN && val == mod)
 497                 return false;
 498         if (sym->visible <= sym->rev_dep.tri)
 499                 return false;
 500         if (sym_is_choice_value(sym) && sym->visible == yes)
 501                 return val == yes;
 502         return val >= sym->rev_dep.tri && val <= sym->visible;
 503 }
 504
 505 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 506 {
 507         tristate oldval = sym_get_tristate_value(sym);
 508
 509         if (oldval != val && !sym_tristate_within_range(sym, val))
 510                 return false;
 511
 512         if (!(sym->flags & SYMBOL_DEF_USER)) {
 513                 sym->flags |= SYMBOL_DEF_USER;
 514                 sym_set_changed(sym);
 515         }
 516         /*
 517          * setting a choice value also resets the new flag of the choice
 518          * symbol and all other choice values.
 519          */
 520         if (sym_is_choice_value(sym) && val == yes) {
 521                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 522                 struct property *prop;
 523                 struct expr *e;
 524
 525                 cs->def[S_DEF_USER].val = sym;
 526                 cs->flags |= SYMBOL_DEF_USER;
 527                 prop = sym_get_choice_prop(cs);
 528                 for (e = prop->expr; e; e = e->left.expr) {
 529                         if (e->right.sym->visible != no)
 530                                 e->right.sym->flags |= SYMBOL_DEF_USER;
 531                 }
 532         }
 533
 534         sym->def[S_DEF_USER].tri = val;
 535         if (oldval != val)
 536                 sym_clear_all_valid();
 537
 538         return true;
 539 }
 540
 541 tristate sym_toggle_tristate_value(struct symbol *sym)
 542 {
 543         tristate oldval, newval;
 544
 545         oldval = newval = sym_get_tristate_value(sym);
 546         do {
 547                 switch (newval) {
 548                 case no:
 549                         newval = mod;
 550                         break;
 551                 case mod:
 552                         newval = yes;
 553                         break;
 554                 case yes:
 555                         newval = no;
 556                         break;
 557                 }
 558                 if (sym_set_tristate_value(sym, newval))
 559                         break;
 560         } while (oldval != newval);
 561         return newval;
 562 }
 563
 564 bool sym_string_valid(struct symbol *sym, const char *str)
 565 {
 566         signed char ch;
 567
 568         switch (sym->type) {
 569         case S_STRING:
 570                 return true;
 571         case S_INT:
 572                 ch = *str++;
 573                 if (ch == '-')
 574                         ch = *str++;
 575                 if (!isdigit(ch))
 576                         return false;
 577                 if (ch == '0' && *str != 0)
 578                         return false;
 579                 while ((ch = *str++)) {
 580                         if (!isdigit(ch))
 581                                 return false;
 582                 }
 583                 return true;
 584         case S_HEX:
 585                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 586                         str += 2;
 587                 ch = *str++;
 588                 do {
 589                         if (!isxdigit(ch))
 590                                 return false;
 591                 } while ((ch = *str++));
 592                 return true;
 593         case S_BOOLEAN:
 594         case S_TRISTATE:
 595                 switch (str[0]) {
 596                 case 'y': case 'Y':
 597                 case 'm': case 'M':
 598                 case 'n': case 'N':
 599                         return true;
 600                 }
 601                 return false;
 602         default:
 603                 return false;
 604         }
 605 }
 606
 607 bool sym_string_within_range(struct symbol *sym, const char *str)
 608 {
 609         struct property *prop;
 610         long long val;
 611
 612         switch (sym->type) {
 613         case S_STRING:
 614                 return sym_string_valid(sym, str);
 615         case S_INT:
 616                 if (!sym_string_valid(sym, str))
 617                         return false;
 618                 prop = sym_get_range_prop(sym);
 619                 if (!prop)
 620                         return true;
 621                 val = strtoll(str, NULL, 10);
 622                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 623                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 624         case S_HEX:
 625                 if (!sym_string_valid(sym, str))
 626                         return false;
 627                 prop = sym_get_range_prop(sym);
 628                 if (!prop)
 629                         return true;
 630                 val = strtoll(str, NULL, 16);
 631                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 632                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 633         case S_BOOLEAN:
 634         case S_TRISTATE:
 635                 switch (str[0]) {
 636                 case 'y': case 'Y':
 637                         return sym_tristate_within_range(sym, yes);
 638                 case 'm': case 'M':
 639                         return sym_tristate_within_range(sym, mod);
 640                 case 'n': case 'N':
 641                         return sym_tristate_within_range(sym, no);
 642                 }
 643                 return false;
 644         default:
 645                 return false;
 646         }
 647 }
 648
 649 bool sym_set_string_value(struct symbol *sym, const char *newval)
 650 {
 651         const char *oldval;
 652         char *val;
 653         int size;
 654
 655         switch (sym->type) {
 656         case S_BOOLEAN:
 657         case S_TRISTATE:
 658                 switch (newval[0]) {
 659                 case 'y': case 'Y':
 660                         return sym_set_tristate_value(sym, yes);
 661                 case 'm': case 'M':
 662                         return sym_set_tristate_value(sym, mod);
 663                 case 'n': case 'N':
 664                         return sym_set_tristate_value(sym, no);
 665                 }
 666                 return false;
 667         default:
 668                 ;
 669         }
 670
 671         if (!sym_string_within_range(sym, newval))
 672                 return false;
 673
 674         if (!(sym->flags & SYMBOL_DEF_USER)) {
 675                 sym->flags |= SYMBOL_DEF_USER;
 676                 sym_set_changed(sym);
 677         }
 678
 679         oldval = sym->def[S_DEF_USER].val;
 680         size = strlen(newval) + 1;
 681         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 682                 size += 2;
 683                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 684                 *val++ = '0';
 685                 *val++ = 'x';
 686         } else if (!oldval || strcmp(oldval, newval))
 687                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 688         else
 689                 return true;
 690
 691         strcpy(val, newval);
 692         free((void *)oldval);
 693         sym_clear_all_valid();
 694
 695         return true;
 696 }
 697
 698 /*
 699  * Find the default value associated to a symbol.
 700  * For tristate symbol handle the modules=n case
 701  * in which case "m" becomes "y".
 702  * If the symbol does not have any default then fallback
 703  * to the fixed default values.
 704  */
 705 const char *sym_get_string_default(struct symbol *sym)
 706 {
 707         struct property *prop;
 708         struct symbol *ds;
 709         const char *str = "";
 710         tristate val;
 711
 712         sym_calc_visibility(sym);
 713         sym_calc_value(modules_sym);
 714         val = symbol_no.curr.tri;
 715
 716         /* If symbol has a default value look it up */
 717         prop = sym_get_default_prop(sym);
 718         if (prop != NULL) {
 719                 switch (sym->type) {
 720                 case S_BOOLEAN:
 721                 case S_TRISTATE:
 722                         /* The visibility may limit the value from yes => mod */
 723                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 724                         break;
 725                 default:
 726                         /*
 727                          * The following fails to handle the situation
 728                          * where a default value is further limited by
 729                          * the valid range.
 730                          */
 731                         ds = prop_get_symbol(prop);
 732                         if (ds != NULL) {
 733                                 sym_calc_value(ds);
 734                                 str = (const char *)ds->curr.val;
 735                         }
 736                 }
 737         }
 738
 739         /* Handle select statements */
 740         val = EXPR_OR(val, sym->rev_dep.tri);
 741
 742         /* transpose mod to yes if modules are not enabled */
 743         if (val == mod)
 744                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 745                         val = yes;
 746
 747         /* transpose mod to yes if type is bool */
 748         if (sym->type == S_BOOLEAN && val == mod)
 749                 val = yes;
 750
 751         /* adjust the default value if this symbol is implied by another */
 752         if (val < sym->implied.tri)
 753                 val = sym->implied.tri;
 754
 755         switch (sym->type) {
 756         case S_BOOLEAN:
 757         case S_TRISTATE:
 758                 switch (val) {
 759                 case no: return "n";
 760                 case mod: return "m";
 761                 case yes: return "y";
 762                 }
 763         case S_INT:
 764                 if (!str[0])
 765                         str = "0";
 766                 break;
 767         case S_HEX:
 768                 if (!str[0])
 769                         str = "0x0";
 770                 break;
 771         default:
 772                 break;
 773         }
 774         return str;
 775 }
 776
 777 const char *sym_get_string_value(struct symbol *sym)
 778 {
 779         tristate val;
 780
 781         switch (sym->type) {
 782         case S_BOOLEAN:
 783         case S_TRISTATE:
 784                 val = sym_get_tristate_value(sym);
 785                 switch (val) {
 786                 case no:
 787                         return "n";
 788                 case mod:
 789                         sym_calc_value(modules_sym);
 790                         return (modules_sym->curr.tri == no) ? "n" : "m";
 791                 case yes:
 792                         return "y";
 793                 }
 794                 break;
 795         default:
 796                 ;
 797         }
 798         return (const char *)sym->curr.val;
 799 }
 800
 801 bool sym_is_changeable(struct symbol *sym)
 802 {
 803         return sym->visible > sym->rev_dep.tri;
 804 }
 805
 806 static unsigned strhash(const char *s)
 807 {
 808         /* fnv32 hash */
 809         unsigned hash = 2166136261U;
 810         for (; *s; s++)
 811                 hash = (hash ^ *s) * 0x01000193;
 812         return hash;
 813 }
 814
 815 struct symbol *sym_lookup(const char *name, int flags)
 816 {
 817         struct symbol *symbol;
 818         char *new_name;
 819         int hash;
 820
 821         if (name) {
 822                 if (name[0] && !name[1]) {
 823                         switch (name[0]) {
 824                         case 'y': return &symbol_yes;
 825                         case 'm': return &symbol_mod;
 826                         case 'n': return &symbol_no;
 827                         }
 828                 }
 829                 hash = strhash(name) % SYMBOL_HASHSIZE;
 830
 831                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 832                         if (symbol->name &&
 833                             !strcmp(symbol->name, name) &&
 834                             (flags ? symbol->flags & flags
 835                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 836                                 return symbol;
 837                 }
 838                 new_name = xstrdup(name);
 839         } else {
 840                 new_name = NULL;
 841                 hash = 0;
 842         }
 843
 844         symbol = xmalloc(sizeof(*symbol));
 845         memset(symbol, 0, sizeof(*symbol));
 846         symbol->name = new_name;
 847         symbol->type = S_UNKNOWN;
 848         symbol->flags = flags;
 849
 850         symbol->next = symbol_hash[hash];
 851         symbol_hash[hash] = symbol;
 852
 853         return symbol;
 854 }
 855
 856 struct symbol *sym_find(const char *name)
 857 {
 858         struct symbol *symbol = NULL;
 859         int hash = 0;
 860
 861         if (!name)
 862                 return NULL;
 863
 864         if (name[0] && !name[1]) {
 865                 switch (name[0]) {
 866                 case 'y': return &symbol_yes;
 867                 case 'm': return &symbol_mod;
 868                 case 'n': return &symbol_no;
 869                 }
 870         }
 871         hash = strhash(name) % SYMBOL_HASHSIZE;
 872
 873         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 874                 if (symbol->name &&
 875                     !strcmp(symbol->name, name) &&
 876                     !(symbol->flags & SYMBOL_CONST))
 877                                 break;
 878         }
 879
 880         return symbol;
 881 }
 882
 883 struct sym_match {
 884         struct symbol   *sym;
 885         off_t           so, eo;
 886 };
 887
 888 /* Compare matched symbols as thus:
 889  * - first, symbols that match exactly
 890  * - then, alphabetical sort
 891  */
 892 static int sym_rel_comp(const void *sym1, const void *sym2)
 893 {
 894         const struct sym_match *s1 = sym1;
 895         const struct sym_match *s2 = sym2;
 896         int exact1, exact2;
 897
 898         /* Exact match:
 899          * - if matched length on symbol s1 is the length of that symbol,
 900          *   then this symbol should come first;
 901          * - if matched length on symbol s2 is the length of that symbol,
 902          *   then this symbol should come first.
 903          * Note: since the search can be a regexp, both symbols may match
 904          * exactly; if this is the case, we can't decide which comes first,
 905          * and we fallback to sorting alphabetically.
 906          */
 907         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 908         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 909         if (exact1 && !exact2)
 910                 return -1;
 911         if (!exact1 && exact2)
 912                 return 1;
 913
 914         /* As a fallback, sort symbols alphabetically */
 915         return strcmp(s1->sym->name, s2->sym->name);
 916 }
 917
 918 struct symbol **sym_re_search(const char *pattern)
 919 {
 920         struct symbol *sym, **sym_arr = NULL;
 921         struct sym_match *sym_match_arr = NULL;
 922         int i, cnt, size;
 923         regex_t re;
 924         regmatch_t match[1];
 925
 926         cnt = size = 0;
 927         /* Skip if empty */
 928         if (strlen(pattern) == 0)
 929                 return NULL;
 930         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 931                 return NULL;
 932
 933         for_all_symbols(i, sym) {
 934                 if (sym->flags & SYMBOL_CONST || !sym->name)
 935                         continue;
 936                 if (regexec(&re, sym->name, 1, match, 0))
 937                         continue;
 938                 if (cnt >= size) {
 939                         void *tmp;
 940                         size += 16;
 941                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 942                         if (!tmp)
 943                                 goto sym_re_search_free;
 944                         sym_match_arr = tmp;
 945                 }
 946                 sym_calc_value(sym);
 947                 /* As regexec returned 0, we know we have a match, so
 948                  * we can use match[0].rm_[se]o without further checks
 949                  */
 950                 sym_match_arr[cnt].so = match[0].rm_so;
 951                 sym_match_arr[cnt].eo = match[0].rm_eo;
 952                 sym_match_arr[cnt++].sym = sym;
 953         }
 954         if (sym_match_arr) {
 955                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 956                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 957                 if (!sym_arr)
 958                         goto sym_re_search_free;
 959                 for (i = 0; i < cnt; i++)
 960                         sym_arr[i] = sym_match_arr[i].sym;
 961                 sym_arr[cnt] = NULL;
 962         }
 963 sym_re_search_free:
 964         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
 965         free(sym_match_arr);
 966         regfree(&re);
 967
 968         return sym_arr;
 969 }
 970
 971 /*
 972  * When we check for recursive dependencies we use a stack to save
 973  * current state so we can print out relevant info to user.
 974  * The entries are located on the call stack so no need to free memory.
 975  * Note insert() remove() must always match to properly clear the stack.
 976  */
 977 static struct dep_stack {
 978         struct dep_stack *prev, *next;
 979         struct symbol *sym;
 980         struct property *prop;
 981         struct expr **expr;
 982 } *check_top;
 983
 984 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
 985 {
 986         memset(stack, 0, sizeof(*stack));
 987         if (check_top)
 988                 check_top->next = stack;
 989         stack->prev = check_top;
 990         stack->sym = sym;
 991         check_top = stack;
 992 }
 993
 994 static void dep_stack_remove(void)
 995 {
 996         check_top = check_top->prev;
 997         if (check_top)
 998                 check_top->next = NULL;
 999 }
1000
1001 /*
1002  * Called when we have detected a recursive dependency.
1003  * check_top point to the top of the stact so we use
1004  * the ->prev pointer to locate the bottom of the stack.
1005  */
1006 static void sym_check_print_recursive(struct symbol *last_sym)
1007 {
1008         struct dep_stack *stack;
1009         struct symbol *sym, *next_sym;
1010         struct menu *menu = NULL;
1011         struct property *prop;
1012         struct dep_stack cv_stack;
1013
1014         if (sym_is_choice_value(last_sym)) {
1015                 dep_stack_insert(&cv_stack, last_sym);
1016                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1017         }
1018
1019         for (stack = check_top; stack != NULL; stack = stack->prev)
1020                 if (stack->sym == last_sym)
1021                         break;
1022         if (!stack) {
1023                 fprintf(stderr, "unexpected recursive dependency error\n");
1024                 return;
1025         }
1026
1027         for (; stack; stack = stack->next) {
1028                 sym = stack->sym;
1029                 next_sym = stack->next ? stack->next->sym : last_sym;
1030                 prop = stack->prop;
1031                 if (prop == NULL)
1032                         prop = stack->sym->prop;
1033
1034                 /* for choice values find the menu entry (used below) */
1035                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1036                         for (prop = sym->prop; prop; prop = prop->next) {
1037                                 menu = prop->menu;
1038                                 if (prop->menu)
1039                                         break;
1040                         }
1041                 }
1042                 if (stack->sym == last_sym)
1043                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1044                                 prop->file->name, prop->lineno);
1045
1046                 if (sym_is_choice(sym)) {
1047                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1048                                 menu->file->name, menu->lineno,
1049                                 sym->name ? sym->name : "<choice>",
1050                                 next_sym->name ? next_sym->name : "<choice>");
1051                 } else if (sym_is_choice_value(sym)) {
1052                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1053                                 menu->file->name, menu->lineno,
1054                                 sym->name ? sym->name : "<choice>",
1055                                 next_sym->name ? next_sym->name : "<choice>");
1056                 } else if (stack->expr == &sym->dir_dep.expr) {
1057                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1058                                 prop->file->name, prop->lineno,
1059                                 sym->name ? sym->name : "<choice>",
1060                                 next_sym->name ? next_sym->name : "<choice>");
1061                 } else if (stack->expr == &sym->rev_dep.expr) {
1062                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1063                                 prop->file->name, prop->lineno,
1064                                 sym->name ? sym->name : "<choice>",
1065                                 next_sym->name ? next_sym->name : "<choice>");
1066                 } else if (stack->expr == &sym->implied.expr) {
1067                         fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1068                                 prop->file->name, prop->lineno,
1069                                 sym->name ? sym->name : "<choice>",
1070                                 next_sym->name ? next_sym->name : "<choice>");
1071                 } else if (stack->expr) {
1072                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1073                                 prop->file->name, prop->lineno,
1074                                 sym->name ? sym->name : "<choice>",
1075                                 prop_get_type_name(prop->type),
1076                                 next_sym->name ? next_sym->name : "<choice>");
1077                 } else {
1078                         fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1079                                 prop->file->name, prop->lineno,
1080                                 sym->name ? sym->name : "<choice>",
1081                                 prop_get_type_name(prop->type),
1082                                 next_sym->name ? next_sym->name : "<choice>");
1083                 }
1084         }
1085
1086         fprintf(stderr,
1087                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1088                 "subsection \"Kconfig recursive dependency limitations\"\n"
1089                 "\n");
1090
1091         if (check_top == &cv_stack)
1092                 dep_stack_remove();
1093 }
1094
1095 static struct symbol *sym_check_expr_deps(struct expr *e)
1096 {
1097         struct symbol *sym;
1098
1099         if (!e)
1100                 return NULL;
1101         switch (e->type) {
1102         case E_OR:
1103         case E_AND:
1104                 sym = sym_check_expr_deps(e->left.expr);
1105                 if (sym)
1106                         return sym;
1107                 return sym_check_expr_deps(e->right.expr);
1108         case E_NOT:
1109                 return sym_check_expr_deps(e->left.expr);
1110         case E_EQUAL:
1111         case E_GEQ:
1112         case E_GTH:
1113         case E_LEQ:
1114         case E_LTH:
1115         case E_UNEQUAL:
1116                 sym = sym_check_deps(e->left.sym);
1117                 if (sym)
1118                         return sym;
1119                 return sym_check_deps(e->right.sym);
1120         case E_SYMBOL:
1121                 return sym_check_deps(e->left.sym);
1122         default:
1123                 break;
1124         }
1125         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1126         return NULL;
1127 }
1128
1129 /* return NULL when dependencies are OK */
1130 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1131 {
1132         struct symbol *sym2;
1133         struct property *prop;
1134         struct dep_stack stack;
1135
1136         dep_stack_insert(&stack, sym);
1137
1138         stack.expr = &sym->dir_dep.expr;
1139         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1140         if (sym2)
1141                 goto out;
1142
1143         stack.expr = &sym->rev_dep.expr;
1144         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1145         if (sym2)
1146                 goto out;
1147
1148         stack.expr = &sym->implied.expr;
1149         sym2 = sym_check_expr_deps(sym->implied.expr);
1150         if (sym2)
1151                 goto out;
1152
1153         stack.expr = NULL;
1154
1155         for (prop = sym->prop; prop; prop = prop->next) {
1156                 if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1157                     prop->type == P_IMPLY)
1158                         continue;
1159                 stack.prop = prop;
1160                 sym2 = sym_check_expr_deps(prop->visible.expr);
1161                 if (sym2)
1162                         break;
1163                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1164                         continue;
1165                 stack.expr = &prop->expr;
1166                 sym2 = sym_check_expr_deps(prop->expr);
1167                 if (sym2)
1168                         break;
1169                 stack.expr = NULL;
1170         }
1171
1172 out:
1173         dep_stack_remove();
1174
1175         return sym2;
1176 }
1177
1178 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1179 {
1180         struct symbol *sym, *sym2;
1181         struct property *prop;
1182         struct expr *e;
1183         struct dep_stack stack;
1184
1185         dep_stack_insert(&stack, choice);
1186
1187         prop = sym_get_choice_prop(choice);
1188         expr_list_for_each_sym(prop->expr, e, sym)
1189                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1190
1191         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1192         sym2 = sym_check_sym_deps(choice);
1193         choice->flags &= ~SYMBOL_CHECK;
1194         if (sym2)
1195                 goto out;
1196
1197         expr_list_for_each_sym(prop->expr, e, sym) {
1198                 sym2 = sym_check_sym_deps(sym);
1199                 if (sym2)
1200                         break;
1201         }
1202 out:
1203         expr_list_for_each_sym(prop->expr, e, sym)
1204                 sym->flags &= ~SYMBOL_CHECK;
1205
1206         if (sym2 && sym_is_choice_value(sym2) &&
1207             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1208                 sym2 = choice;
1209
1210         dep_stack_remove();
1211
1212         return sym2;
1213 }
1214
1215 struct symbol *sym_check_deps(struct symbol *sym)
1216 {
1217         struct symbol *sym2;
1218         struct property *prop;
1219
1220         if (sym->flags & SYMBOL_CHECK) {
1221                 sym_check_print_recursive(sym);
1222                 return sym;
1223         }
1224         if (sym->flags & SYMBOL_CHECKED)
1225                 return NULL;
1226
1227         if (sym_is_choice_value(sym)) {
1228                 struct dep_stack stack;
1229
1230                 /* for choice groups start the check with main choice symbol */
1231                 dep_stack_insert(&stack, sym);
1232                 prop = sym_get_choice_prop(sym);
1233                 sym2 = sym_check_deps(prop_get_symbol(prop));
1234                 dep_stack_remove();
1235         } else if (sym_is_choice(sym)) {
1236                 sym2 = sym_check_choice_deps(sym);
1237         } else {
1238                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1239                 sym2 = sym_check_sym_deps(sym);
1240                 sym->flags &= ~SYMBOL_CHECK;
1241         }
1242
1243         return sym2;
1244 }
1245
1246 struct symbol *prop_get_symbol(struct property *prop)
1247 {
1248         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1249                            prop->expr->type == E_LIST))
1250                 return prop->expr->left.sym;
1251         return NULL;
1252 }
1253
1254 const char *prop_get_type_name(enum prop_type type)
1255 {
1256         switch (type) {
1257         case P_PROMPT:
1258                 return "prompt";
1259         case P_COMMENT:
1260                 return "comment";
1261         case P_MENU:
1262                 return "menu";
1263         case P_DEFAULT:
1264                 return "default";
1265         case P_CHOICE:
1266                 return "choice";
1267         case P_SELECT:
1268                 return "select";
1269         case P_IMPLY:
1270                 return "imply";
1271         case P_RANGE:
1272                 return "range";
1273         case P_SYMBOL:
1274                 return "symbol";
1275         case P_UNKNOWN:
1276                 break;
1277         }
1278         return "unknown";
1279 }