scripts/kconfig/symbol.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   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 #include "lkc.h"
  13
  14 struct symbol symbol_yes = {
  15         .name = "y",
  16         .curr = { "y", yes },
  17         .flags = SYMBOL_CONST|SYMBOL_VALID,
  18 }, symbol_mod = {
  19         .name = "m",
  20         .curr = { "m", mod },
  21         .flags = SYMBOL_CONST|SYMBOL_VALID,
  22 }, symbol_no = {
  23         .name = "n",
  24         .curr = { "n", no },
  25         .flags = SYMBOL_CONST|SYMBOL_VALID,
  26 }, symbol_empty = {
  27         .name = "",
  28         .curr = { "", no },
  29         .flags = SYMBOL_VALID,
  30 };
  31
  32 struct symbol *sym_defconfig_list;
  33 struct symbol *modules_sym;
  34 tristate modules_val;
  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         int base;
 121         long long val, val2;
 122         char str[64];
 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         val2 = sym_get_range_val(prop->expr->left.sym, base);
 139         if (val >= val2) {
 140                 val2 = sym_get_range_val(prop->expr->right.sym, base);
 141                 if (val <= val2)
 142                         return;
 143         }
 144         if (sym->type == S_INT)
 145                 sprintf(str, "%lld", val2);
 146         else
 147                 sprintf(str, "0x%llx", val2);
 148         sym->curr.val = xstrdup(str);
 149 }
 150
 151 static void sym_set_changed(struct symbol *sym)
 152 {
 153         struct property *prop;
 154
 155         sym->flags |= SYMBOL_CHANGED;
 156         for (prop = sym->prop; prop; prop = prop->next) {
 157                 if (prop->menu)
 158                         prop->menu->flags |= MENU_CHANGED;
 159         }
 160 }
 161
 162 static void sym_set_all_changed(void)
 163 {
 164         struct symbol *sym;
 165         int i;
 166
 167         for_all_symbols(i, sym)
 168                 sym_set_changed(sym);
 169 }
 170
 171 static void sym_calc_visibility(struct symbol *sym)
 172 {
 173         struct property *prop;
 174         struct symbol *choice_sym = NULL;
 175         tristate tri;
 176
 177         /* any prompt visible? */
 178         tri = no;
 179
 180         if (sym_is_choice_value(sym))
 181                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 182
 183         for_all_prompts(sym, prop) {
 184                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 185                 /*
 186                  * Tristate choice_values with visibility 'mod' are
 187                  * not visible if the corresponding choice's value is
 188                  * 'yes'.
 189                  */
 190                 if (choice_sym && sym->type == S_TRISTATE &&
 191                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
 192                         prop->visible.tri = no;
 193
 194                 tri = EXPR_OR(tri, prop->visible.tri);
 195         }
 196         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 197                 tri = yes;
 198         if (sym->visible != tri) {
 199                 sym->visible = tri;
 200                 sym_set_changed(sym);
 201         }
 202         if (sym_is_choice_value(sym))
 203                 return;
 204         /* defaulting to "yes" if no explicit "depends on" are given */
 205         tri = yes;
 206         if (sym->dir_dep.expr)
 207                 tri = expr_calc_value(sym->dir_dep.expr);
 208         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 209                 tri = yes;
 210         if (sym->dir_dep.tri != tri) {
 211                 sym->dir_dep.tri = tri;
 212                 sym_set_changed(sym);
 213         }
 214         tri = no;
 215         if (sym->rev_dep.expr)
 216                 tri = expr_calc_value(sym->rev_dep.expr);
 217         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 218                 tri = yes;
 219         if (sym->rev_dep.tri != tri) {
 220                 sym->rev_dep.tri = tri;
 221                 sym_set_changed(sym);
 222         }
 223         tri = no;
 224         if (sym->implied.expr)
 225                 tri = expr_calc_value(sym->implied.expr);
 226         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 227                 tri = yes;
 228         if (sym->implied.tri != tri) {
 229                 sym->implied.tri = tri;
 230                 sym_set_changed(sym);
 231         }
 232 }
 233
 234 /*
 235  * Find the default symbol for a choice.
 236  * First try the default values for the choice symbol
 237  * Next locate the first visible choice value
 238  * Return NULL if none was found
 239  */
 240 struct symbol *sym_choice_default(struct symbol *sym)
 241 {
 242         struct symbol *def_sym;
 243         struct property *prop;
 244         struct expr *e;
 245
 246         /* any of the defaults visible? */
 247         for_all_defaults(sym, prop) {
 248                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 249                 if (prop->visible.tri == no)
 250                         continue;
 251                 def_sym = prop_get_symbol(prop);
 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         expr_list_for_each_sym(prop->expr, e, def_sym)
 259                 if (def_sym->visible != no)
 260                         return def_sym;
 261
 262         /* failed to locate any defaults */
 263         return NULL;
 264 }
 265
 266 static struct symbol *sym_calc_choice(struct symbol *sym)
 267 {
 268         struct symbol *def_sym;
 269         struct property *prop;
 270         struct expr *e;
 271         int flags;
 272
 273         /* first calculate all choice values' visibilities */
 274         flags = sym->flags;
 275         prop = sym_get_choice_prop(sym);
 276         expr_list_for_each_sym(prop->expr, e, def_sym) {
 277                 sym_calc_visibility(def_sym);
 278                 if (def_sym->visible != no)
 279                         flags &= def_sym->flags;
 280         }
 281
 282         sym->flags &= flags | ~SYMBOL_DEF_USER;
 283
 284         /* is the user choice visible? */
 285         def_sym = sym->def[S_DEF_USER].val;
 286         if (def_sym && def_sym->visible != no)
 287                 return def_sym;
 288
 289         def_sym = sym_choice_default(sym);
 290
 291         if (def_sym == NULL)
 292                 /* no choice? reset tristate value */
 293                 sym->curr.tri = no;
 294
 295         return def_sym;
 296 }
 297
 298 static void sym_warn_unmet_dep(struct symbol *sym)
 299 {
 300         struct gstr gs = str_new();
 301
 302         str_printf(&gs,
 303                    "\nWARNING: unmet direct dependencies detected for %s\n",
 304                    sym->name);
 305         str_printf(&gs,
 306                    "  Depends on [%c]: ",
 307                    sym->dir_dep.tri == mod ? 'm' : 'n');
 308         expr_gstr_print(sym->dir_dep.expr, &gs);
 309         str_printf(&gs, "\n");
 310
 311         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 312                                "  Selected by [y]:\n");
 313         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 314                                "  Selected by [m]:\n");
 315
 316         fputs(str_get(&gs), stderr);
 317 }
 318
 319 void sym_calc_value(struct symbol *sym)
 320 {
 321         struct symbol_value newval, oldval;
 322         struct property *prop;
 323         struct expr *e;
 324
 325         if (!sym)
 326                 return;
 327
 328         if (sym->flags & SYMBOL_VALID)
 329                 return;
 330
 331         if (sym_is_choice_value(sym) &&
 332             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 333                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 334                 prop = sym_get_choice_prop(sym);
 335                 sym_calc_value(prop_get_symbol(prop));
 336         }
 337
 338         sym->flags |= SYMBOL_VALID;
 339
 340         oldval = sym->curr;
 341
 342         switch (sym->type) {
 343         case S_INT:
 344         case S_HEX:
 345         case S_STRING:
 346                 newval = symbol_empty.curr;
 347                 break;
 348         case S_BOOLEAN:
 349         case S_TRISTATE:
 350                 newval = symbol_no.curr;
 351                 break;
 352         default:
 353                 sym->curr.val = sym->name;
 354                 sym->curr.tri = no;
 355                 return;
 356         }
 357         sym->flags &= ~SYMBOL_WRITE;
 358
 359         sym_calc_visibility(sym);
 360
 361         if (sym->visible != no)
 362                 sym->flags |= SYMBOL_WRITE;
 363
 364         /* set default if recursively called */
 365         sym->curr = newval;
 366
 367         switch (sym_get_type(sym)) {
 368         case S_BOOLEAN:
 369         case S_TRISTATE:
 370                 if (sym_is_choice_value(sym) && sym->visible == yes) {
 371                         prop = sym_get_choice_prop(sym);
 372                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 373                 } else {
 374                         if (sym->visible != no) {
 375                                 /* if the symbol is visible use the user value
 376                                  * if available, otherwise try the default value
 377                                  */
 378                                 if (sym_has_value(sym)) {
 379                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 380                                                               sym->visible);
 381                                         goto calc_newval;
 382                                 }
 383                         }
 384                         if (sym->rev_dep.tri != no)
 385                                 sym->flags |= SYMBOL_WRITE;
 386                         if (!sym_is_choice(sym)) {
 387                                 prop = sym_get_default_prop(sym);
 388                                 if (prop) {
 389                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 390                                                               prop->visible.tri);
 391                                         if (newval.tri != no)
 392                                                 sym->flags |= SYMBOL_WRITE;
 393                                 }
 394                                 if (sym->implied.tri != no) {
 395                                         sym->flags |= SYMBOL_WRITE;
 396                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 397                                         newval.tri = EXPR_AND(newval.tri,
 398                                                               sym->dir_dep.tri);
 399                                 }
 400                         }
 401                 calc_newval:
 402                         if (sym->dir_dep.tri < sym->rev_dep.tri)
 403                                 sym_warn_unmet_dep(sym);
 404                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 405                 }
 406                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 407                         newval.tri = yes;
 408                 break;
 409         case S_STRING:
 410         case S_HEX:
 411         case S_INT:
 412                 if (sym->visible != no && sym_has_value(sym)) {
 413                         newval.val = sym->def[S_DEF_USER].val;
 414                         break;
 415                 }
 416                 prop = sym_get_default_prop(sym);
 417                 if (prop) {
 418                         struct symbol *ds = prop_get_symbol(prop);
 419                         if (ds) {
 420                                 sym->flags |= SYMBOL_WRITE;
 421                                 sym_calc_value(ds);
 422                                 newval.val = ds->curr.val;
 423                         }
 424                 }
 425                 break;
 426         default:
 427                 ;
 428         }
 429
 430         sym->curr = newval;
 431         if (sym_is_choice(sym) && newval.tri == yes)
 432                 sym->curr.val = sym_calc_choice(sym);
 433         sym_validate_range(sym);
 434
 435         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 436                 sym_set_changed(sym);
 437                 if (modules_sym == sym) {
 438                         sym_set_all_changed();
 439                         modules_val = modules_sym->curr.tri;
 440                 }
 441         }
 442
 443         if (sym_is_choice(sym)) {
 444                 struct symbol *choice_sym;
 445
 446                 prop = sym_get_choice_prop(sym);
 447                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
 448                         if ((sym->flags & SYMBOL_WRITE) &&
 449                             choice_sym->visible != no)
 450                                 choice_sym->flags |= SYMBOL_WRITE;
 451                         if (sym->flags & SYMBOL_CHANGED)
 452                                 sym_set_changed(choice_sym);
 453                 }
 454         }
 455
 456         if (sym->flags & SYMBOL_NO_WRITE)
 457                 sym->flags &= ~SYMBOL_WRITE;
 458
 459         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 460                 set_all_choice_values(sym);
 461 }
 462
 463 void sym_clear_all_valid(void)
 464 {
 465         struct symbol *sym;
 466         int i;
 467
 468         for_all_symbols(i, sym)
 469                 sym->flags &= ~SYMBOL_VALID;
 470         sym_add_change_count(1);
 471         sym_calc_value(modules_sym);
 472 }
 473
 474 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 475 {
 476         int type = sym_get_type(sym);
 477
 478         if (sym->visible == no)
 479                 return false;
 480
 481         if (type != S_BOOLEAN && type != S_TRISTATE)
 482                 return false;
 483
 484         if (type == S_BOOLEAN && val == mod)
 485                 return false;
 486         if (sym->visible <= sym->rev_dep.tri)
 487                 return false;
 488         if (sym_is_choice_value(sym) && sym->visible == yes)
 489                 return val == yes;
 490         return val >= sym->rev_dep.tri && val <= sym->visible;
 491 }
 492
 493 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 494 {
 495         tristate oldval = sym_get_tristate_value(sym);
 496
 497         if (oldval != val && !sym_tristate_within_range(sym, val))
 498                 return false;
 499
 500         if (!(sym->flags & SYMBOL_DEF_USER)) {
 501                 sym->flags |= SYMBOL_DEF_USER;
 502                 sym_set_changed(sym);
 503         }
 504         /*
 505          * setting a choice value also resets the new flag of the choice
 506          * symbol and all other choice values.
 507          */
 508         if (sym_is_choice_value(sym) && val == yes) {
 509                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 510                 struct property *prop;
 511                 struct expr *e;
 512
 513                 cs->def[S_DEF_USER].val = sym;
 514                 cs->flags |= SYMBOL_DEF_USER;
 515                 prop = sym_get_choice_prop(cs);
 516                 for (e = prop->expr; e; e = e->left.expr) {
 517                         if (e->right.sym->visible != no)
 518                                 e->right.sym->flags |= SYMBOL_DEF_USER;
 519                 }
 520         }
 521
 522         sym->def[S_DEF_USER].tri = val;
 523         if (oldval != val)
 524                 sym_clear_all_valid();
 525
 526         return true;
 527 }
 528
 529 tristate sym_toggle_tristate_value(struct symbol *sym)
 530 {
 531         tristate oldval, newval;
 532
 533         oldval = newval = sym_get_tristate_value(sym);
 534         do {
 535                 switch (newval) {
 536                 case no:
 537                         newval = mod;
 538                         break;
 539                 case mod:
 540                         newval = yes;
 541                         break;
 542                 case yes:
 543                         newval = no;
 544                         break;
 545                 }
 546                 if (sym_set_tristate_value(sym, newval))
 547                         break;
 548         } while (oldval != newval);
 549         return newval;
 550 }
 551
 552 bool sym_string_valid(struct symbol *sym, const char *str)
 553 {
 554         signed char ch;
 555
 556         switch (sym->type) {
 557         case S_STRING:
 558                 return true;
 559         case S_INT:
 560                 ch = *str++;
 561                 if (ch == '-')
 562                         ch = *str++;
 563                 if (!isdigit(ch))
 564                         return false;
 565                 if (ch == '0' && *str != 0)
 566                         return false;
 567                 while ((ch = *str++)) {
 568                         if (!isdigit(ch))
 569                                 return false;
 570                 }
 571                 return true;
 572         case S_HEX:
 573                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 574                         str += 2;
 575                 ch = *str++;
 576                 do {
 577                         if (!isxdigit(ch))
 578                                 return false;
 579                 } while ((ch = *str++));
 580                 return true;
 581         case S_BOOLEAN:
 582         case S_TRISTATE:
 583                 switch (str[0]) {
 584                 case 'y': case 'Y':
 585                 case 'm': case 'M':
 586                 case 'n': case 'N':
 587                         return true;
 588                 }
 589                 return false;
 590         default:
 591                 return false;
 592         }
 593 }
 594
 595 bool sym_string_within_range(struct symbol *sym, const char *str)
 596 {
 597         struct property *prop;
 598         long long val;
 599
 600         switch (sym->type) {
 601         case S_STRING:
 602                 return sym_string_valid(sym, str);
 603         case S_INT:
 604                 if (!sym_string_valid(sym, str))
 605                         return false;
 606                 prop = sym_get_range_prop(sym);
 607                 if (!prop)
 608                         return true;
 609                 val = strtoll(str, NULL, 10);
 610                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 611                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 612         case S_HEX:
 613                 if (!sym_string_valid(sym, str))
 614                         return false;
 615                 prop = sym_get_range_prop(sym);
 616                 if (!prop)
 617                         return true;
 618                 val = strtoll(str, NULL, 16);
 619                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 620                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 621         case S_BOOLEAN:
 622         case S_TRISTATE:
 623                 switch (str[0]) {
 624                 case 'y': case 'Y':
 625                         return sym_tristate_within_range(sym, yes);
 626                 case 'm': case 'M':
 627                         return sym_tristate_within_range(sym, mod);
 628                 case 'n': case 'N':
 629                         return sym_tristate_within_range(sym, no);
 630                 }
 631                 return false;
 632         default:
 633                 return false;
 634         }
 635 }
 636
 637 bool sym_set_string_value(struct symbol *sym, const char *newval)
 638 {
 639         const char *oldval;
 640         char *val;
 641         int size;
 642
 643         switch (sym->type) {
 644         case S_BOOLEAN:
 645         case S_TRISTATE:
 646                 switch (newval[0]) {
 647                 case 'y': case 'Y':
 648                         return sym_set_tristate_value(sym, yes);
 649                 case 'm': case 'M':
 650                         return sym_set_tristate_value(sym, mod);
 651                 case 'n': case 'N':
 652                         return sym_set_tristate_value(sym, no);
 653                 }
 654                 return false;
 655         default:
 656                 ;
 657         }
 658
 659         if (!sym_string_within_range(sym, newval))
 660                 return false;
 661
 662         if (!(sym->flags & SYMBOL_DEF_USER)) {
 663                 sym->flags |= SYMBOL_DEF_USER;
 664                 sym_set_changed(sym);
 665         }
 666
 667         oldval = sym->def[S_DEF_USER].val;
 668         size = strlen(newval) + 1;
 669         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 670                 size += 2;
 671                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 672                 *val++ = '0';
 673                 *val++ = 'x';
 674         } else if (!oldval || strcmp(oldval, newval))
 675                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 676         else
 677                 return true;
 678
 679         strcpy(val, newval);
 680         free((void *)oldval);
 681         sym_clear_all_valid();
 682
 683         return true;
 684 }
 685
 686 /*
 687  * Find the default value associated to a symbol.
 688  * For tristate symbol handle the modules=n case
 689  * in which case "m" becomes "y".
 690  * If the symbol does not have any default then fallback
 691  * to the fixed default values.
 692  */
 693 const char *sym_get_string_default(struct symbol *sym)
 694 {
 695         struct property *prop;
 696         struct symbol *ds;
 697         const char *str;
 698         tristate val;
 699
 700         sym_calc_visibility(sym);
 701         sym_calc_value(modules_sym);
 702         val = symbol_no.curr.tri;
 703         str = symbol_empty.curr.val;
 704
 705         /* If symbol has a default value look it up */
 706         prop = sym_get_default_prop(sym);
 707         if (prop != NULL) {
 708                 switch (sym->type) {
 709                 case S_BOOLEAN:
 710                 case S_TRISTATE:
 711                         /* The visibility may limit the value from yes => mod */
 712                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 713                         break;
 714                 default:
 715                         /*
 716                          * The following fails to handle the situation
 717                          * where a default value is further limited by
 718                          * the valid range.
 719                          */
 720                         ds = prop_get_symbol(prop);
 721                         if (ds != NULL) {
 722                                 sym_calc_value(ds);
 723                                 str = (const char *)ds->curr.val;
 724                         }
 725                 }
 726         }
 727
 728         /* Handle select statements */
 729         val = EXPR_OR(val, sym->rev_dep.tri);
 730
 731         /* transpose mod to yes if modules are not enabled */
 732         if (val == mod)
 733                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 734                         val = yes;
 735
 736         /* transpose mod to yes if type is bool */
 737         if (sym->type == S_BOOLEAN && val == mod)
 738                 val = yes;
 739
 740         /* adjust the default value if this symbol is implied by another */
 741         if (val < sym->implied.tri)
 742                 val = sym->implied.tri;
 743
 744         switch (sym->type) {
 745         case S_BOOLEAN:
 746         case S_TRISTATE:
 747                 switch (val) {
 748                 case no: return "n";
 749                 case mod: return "m";
 750                 case yes: return "y";
 751                 }
 752         case S_INT:
 753         case S_HEX:
 754                 return str;
 755         case S_STRING:
 756                 return str;
 757         case S_UNKNOWN:
 758                 break;
 759         }
 760         return "";
 761 }
 762
 763 const char *sym_get_string_value(struct symbol *sym)
 764 {
 765         tristate val;
 766
 767         switch (sym->type) {
 768         case S_BOOLEAN:
 769         case S_TRISTATE:
 770                 val = sym_get_tristate_value(sym);
 771                 switch (val) {
 772                 case no:
 773                         return "n";
 774                 case mod:
 775                         sym_calc_value(modules_sym);
 776                         return (modules_sym->curr.tri == no) ? "n" : "m";
 777                 case yes:
 778                         return "y";
 779                 }
 780                 break;
 781         default:
 782                 ;
 783         }
 784         return (const char *)sym->curr.val;
 785 }
 786
 787 bool sym_is_changeable(struct symbol *sym)
 788 {
 789         return sym->visible > sym->rev_dep.tri;
 790 }
 791
 792 static unsigned strhash(const char *s)
 793 {
 794         /* fnv32 hash */
 795         unsigned hash = 2166136261U;
 796         for (; *s; s++)
 797                 hash = (hash ^ *s) * 0x01000193;
 798         return hash;
 799 }
 800
 801 struct symbol *sym_lookup(const char *name, int flags)
 802 {
 803         struct symbol *symbol;
 804         char *new_name;
 805         int hash;
 806
 807         if (name) {
 808                 if (name[0] && !name[1]) {
 809                         switch (name[0]) {
 810                         case 'y': return &symbol_yes;
 811                         case 'm': return &symbol_mod;
 812                         case 'n': return &symbol_no;
 813                         }
 814                 }
 815                 hash = strhash(name) % SYMBOL_HASHSIZE;
 816
 817                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 818                         if (symbol->name &&
 819                             !strcmp(symbol->name, name) &&
 820                             (flags ? symbol->flags & flags
 821                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 822                                 return symbol;
 823                 }
 824                 new_name = xstrdup(name);
 825         } else {
 826                 new_name = NULL;
 827                 hash = 0;
 828         }
 829
 830         symbol = xmalloc(sizeof(*symbol));
 831         memset(symbol, 0, sizeof(*symbol));
 832         symbol->name = new_name;
 833         symbol->type = S_UNKNOWN;
 834         symbol->flags |= flags;
 835
 836         symbol->next = symbol_hash[hash];
 837         symbol_hash[hash] = symbol;
 838
 839         return symbol;
 840 }
 841
 842 struct symbol *sym_find(const char *name)
 843 {
 844         struct symbol *symbol = NULL;
 845         int hash = 0;
 846
 847         if (!name)
 848                 return NULL;
 849
 850         if (name[0] && !name[1]) {
 851                 switch (name[0]) {
 852                 case 'y': return &symbol_yes;
 853                 case 'm': return &symbol_mod;
 854                 case 'n': return &symbol_no;
 855                 }
 856         }
 857         hash = strhash(name) % SYMBOL_HASHSIZE;
 858
 859         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 860                 if (symbol->name &&
 861                     !strcmp(symbol->name, name) &&
 862                     !(symbol->flags & SYMBOL_CONST))
 863                                 break;
 864         }
 865
 866         return symbol;
 867 }
 868
 869 const char *sym_escape_string_value(const char *in)
 870 {
 871         const char *p;
 872         size_t reslen;
 873         char *res;
 874         size_t l;
 875
 876         reslen = strlen(in) + strlen("\"\"") + 1;
 877
 878         p = in;
 879         for (;;) {
 880                 l = strcspn(p, "\"\\");
 881                 p += l;
 882
 883                 if (p[0] == '\0')
 884                         break;
 885
 886                 reslen++;
 887                 p++;
 888         }
 889
 890         res = xmalloc(reslen);
 891         res[0] = '\0';
 892
 893         strcat(res, "\"");
 894
 895         p = in;
 896         for (;;) {
 897                 l = strcspn(p, "\"\\");
 898                 strncat(res, p, l);
 899                 p += l;
 900
 901                 if (p[0] == '\0')
 902                         break;
 903
 904                 strcat(res, "\\");
 905                 strncat(res, p++, 1);
 906         }
 907
 908         strcat(res, "\"");
 909         return res;
 910 }
 911
 912 struct sym_match {
 913         struct symbol   *sym;
 914         off_t           so, eo;
 915 };
 916
 917 /* Compare matched symbols as thus:
 918  * - first, symbols that match exactly
 919  * - then, alphabetical sort
 920  */
 921 static int sym_rel_comp(const void *sym1, const void *sym2)
 922 {
 923         const struct sym_match *s1 = sym1;
 924         const struct sym_match *s2 = sym2;
 925         int exact1, exact2;
 926
 927         /* Exact match:
 928          * - if matched length on symbol s1 is the length of that symbol,
 929          *   then this symbol should come first;
 930          * - if matched length on symbol s2 is the length of that symbol,
 931          *   then this symbol should come first.
 932          * Note: since the search can be a regexp, both symbols may match
 933          * exactly; if this is the case, we can't decide which comes first,
 934          * and we fallback to sorting alphabetically.
 935          */
 936         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 937         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 938         if (exact1 && !exact2)
 939                 return -1;
 940         if (!exact1 && exact2)
 941                 return 1;
 942
 943         /* As a fallback, sort symbols alphabetically */
 944         return strcmp(s1->sym->name, s2->sym->name);
 945 }
 946
 947 struct symbol **sym_re_search(const char *pattern)
 948 {
 949         struct symbol *sym, **sym_arr = NULL;
 950         struct sym_match *sym_match_arr = NULL;
 951         int i, cnt, size;
 952         regex_t re;
 953         regmatch_t match[1];
 954
 955         cnt = size = 0;
 956         /* Skip if empty */
 957         if (strlen(pattern) == 0)
 958                 return NULL;
 959         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 960                 return NULL;
 961
 962         for_all_symbols(i, sym) {
 963                 if (sym->flags & SYMBOL_CONST || !sym->name)
 964                         continue;
 965                 if (regexec(&re, sym->name, 1, match, 0))
 966                         continue;
 967                 if (cnt >= size) {
 968                         void *tmp;
 969                         size += 16;
 970                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 971                         if (!tmp)
 972                                 goto sym_re_search_free;
 973                         sym_match_arr = tmp;
 974                 }
 975                 sym_calc_value(sym);
 976                 /* As regexec returned 0, we know we have a match, so
 977                  * we can use match[0].rm_[se]o without further checks
 978                  */
 979                 sym_match_arr[cnt].so = match[0].rm_so;
 980                 sym_match_arr[cnt].eo = match[0].rm_eo;
 981                 sym_match_arr[cnt++].sym = sym;
 982         }
 983         if (sym_match_arr) {
 984                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 985                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 986                 if (!sym_arr)
 987                         goto sym_re_search_free;
 988                 for (i = 0; i < cnt; i++)
 989                         sym_arr[i] = sym_match_arr[i].sym;
 990                 sym_arr[cnt] = NULL;
 991         }
 992 sym_re_search_free:
 993         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
 994         free(sym_match_arr);
 995         regfree(&re);
 996
 997         return sym_arr;
 998 }
 999
1000 /*
1001  * When we check for recursive dependencies we use a stack to save
1002  * current state so we can print out relevant info to user.
1003  * The entries are located on the call stack so no need to free memory.
1004  * Note insert() remove() must always match to properly clear the stack.
1005  */
1006 static struct dep_stack {
1007         struct dep_stack *prev, *next;
1008         struct symbol *sym;
1009         struct property *prop;
1010         struct expr **expr;
1011 } *check_top;
1012
1013 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1014 {
1015         memset(stack, 0, sizeof(*stack));
1016         if (check_top)
1017                 check_top->next = stack;
1018         stack->prev = check_top;
1019         stack->sym = sym;
1020         check_top = stack;
1021 }
1022
1023 static void dep_stack_remove(void)
1024 {
1025         check_top = check_top->prev;
1026         if (check_top)
1027                 check_top->next = NULL;
1028 }
1029
1030 /*
1031  * Called when we have detected a recursive dependency.
1032  * check_top point to the top of the stact so we use
1033  * the ->prev pointer to locate the bottom of the stack.
1034  */
1035 static void sym_check_print_recursive(struct symbol *last_sym)
1036 {
1037         struct dep_stack *stack;
1038         struct symbol *sym, *next_sym;
1039         struct menu *menu = NULL;
1040         struct property *prop;
1041         struct dep_stack cv_stack;
1042
1043         if (sym_is_choice_value(last_sym)) {
1044                 dep_stack_insert(&cv_stack, last_sym);
1045                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1046         }
1047
1048         for (stack = check_top; stack != NULL; stack = stack->prev)
1049                 if (stack->sym == last_sym)
1050                         break;
1051         if (!stack) {
1052                 fprintf(stderr, "unexpected recursive dependency error\n");
1053                 return;
1054         }
1055
1056         for (; stack; stack = stack->next) {
1057                 sym = stack->sym;
1058                 next_sym = stack->next ? stack->next->sym : last_sym;
1059                 prop = stack->prop;
1060                 if (prop == NULL)
1061                         prop = stack->sym->prop;
1062
1063                 /* for choice values find the menu entry (used below) */
1064                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1065                         for (prop = sym->prop; prop; prop = prop->next) {
1066                                 menu = prop->menu;
1067                                 if (prop->menu)
1068                                         break;
1069                         }
1070                 }
1071                 if (stack->sym == last_sym)
1072                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1073                                 prop->file->name, prop->lineno);
1074
1075                 if (sym_is_choice(sym)) {
1076                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1077                                 menu->file->name, menu->lineno,
1078                                 sym->name ? sym->name : "<choice>",
1079                                 next_sym->name ? next_sym->name : "<choice>");
1080                 } else if (sym_is_choice_value(sym)) {
1081                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1082                                 menu->file->name, menu->lineno,
1083                                 sym->name ? sym->name : "<choice>",
1084                                 next_sym->name ? next_sym->name : "<choice>");
1085                 } else if (stack->expr == &sym->dir_dep.expr) {
1086                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1087                                 prop->file->name, prop->lineno,
1088                                 sym->name ? sym->name : "<choice>",
1089                                 next_sym->name ? next_sym->name : "<choice>");
1090                 } else if (stack->expr == &sym->rev_dep.expr) {
1091                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1092                                 prop->file->name, prop->lineno,
1093                                 sym->name ? sym->name : "<choice>",
1094                                 next_sym->name ? next_sym->name : "<choice>");
1095                 } else if (stack->expr == &sym->implied.expr) {
1096                         fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1097                                 prop->file->name, prop->lineno,
1098                                 sym->name ? sym->name : "<choice>",
1099                                 next_sym->name ? next_sym->name : "<choice>");
1100                 } else if (stack->expr) {
1101                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1102                                 prop->file->name, prop->lineno,
1103                                 sym->name ? sym->name : "<choice>",
1104                                 prop_get_type_name(prop->type),
1105                                 next_sym->name ? next_sym->name : "<choice>");
1106                 } else {
1107                         fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1108                                 prop->file->name, prop->lineno,
1109                                 sym->name ? sym->name : "<choice>",
1110                                 prop_get_type_name(prop->type),
1111                                 next_sym->name ? next_sym->name : "<choice>");
1112                 }
1113         }
1114
1115         fprintf(stderr,
1116                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1117                 "subsection \"Kconfig recursive dependency limitations\"\n"
1118                 "\n");
1119
1120         if (check_top == &cv_stack)
1121                 dep_stack_remove();
1122 }
1123
1124 static struct symbol *sym_check_expr_deps(struct expr *e)
1125 {
1126         struct symbol *sym;
1127
1128         if (!e)
1129                 return NULL;
1130         switch (e->type) {
1131         case E_OR:
1132         case E_AND:
1133                 sym = sym_check_expr_deps(e->left.expr);
1134                 if (sym)
1135                         return sym;
1136                 return sym_check_expr_deps(e->right.expr);
1137         case E_NOT:
1138                 return sym_check_expr_deps(e->left.expr);
1139         case E_EQUAL:
1140         case E_GEQ:
1141         case E_GTH:
1142         case E_LEQ:
1143         case E_LTH:
1144         case E_UNEQUAL:
1145                 sym = sym_check_deps(e->left.sym);
1146                 if (sym)
1147                         return sym;
1148                 return sym_check_deps(e->right.sym);
1149         case E_SYMBOL:
1150                 return sym_check_deps(e->left.sym);
1151         default:
1152                 break;
1153         }
1154         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1155         return NULL;
1156 }
1157
1158 /* return NULL when dependencies are OK */
1159 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1160 {
1161         struct symbol *sym2;
1162         struct property *prop;
1163         struct dep_stack stack;
1164
1165         dep_stack_insert(&stack, sym);
1166
1167         stack.expr = &sym->dir_dep.expr;
1168         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1169         if (sym2)
1170                 goto out;
1171
1172         stack.expr = &sym->rev_dep.expr;
1173         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1174         if (sym2)
1175                 goto out;
1176
1177         stack.expr = &sym->implied.expr;
1178         sym2 = sym_check_expr_deps(sym->implied.expr);
1179         if (sym2)
1180                 goto out;
1181
1182         stack.expr = NULL;
1183
1184         for (prop = sym->prop; prop; prop = prop->next) {
1185                 if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1186                     prop->type == P_IMPLY)
1187                         continue;
1188                 stack.prop = prop;
1189                 sym2 = sym_check_expr_deps(prop->visible.expr);
1190                 if (sym2)
1191                         break;
1192                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1193                         continue;
1194                 stack.expr = &prop->expr;
1195                 sym2 = sym_check_expr_deps(prop->expr);
1196                 if (sym2)
1197                         break;
1198                 stack.expr = NULL;
1199         }
1200
1201 out:
1202         dep_stack_remove();
1203
1204         return sym2;
1205 }
1206
1207 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1208 {
1209         struct symbol *sym, *sym2;
1210         struct property *prop;
1211         struct expr *e;
1212         struct dep_stack stack;
1213
1214         dep_stack_insert(&stack, choice);
1215
1216         prop = sym_get_choice_prop(choice);
1217         expr_list_for_each_sym(prop->expr, e, sym)
1218                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1219
1220         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1221         sym2 = sym_check_sym_deps(choice);
1222         choice->flags &= ~SYMBOL_CHECK;
1223         if (sym2)
1224                 goto out;
1225
1226         expr_list_for_each_sym(prop->expr, e, sym) {
1227                 sym2 = sym_check_sym_deps(sym);
1228                 if (sym2)
1229                         break;
1230         }
1231 out:
1232         expr_list_for_each_sym(prop->expr, e, sym)
1233                 sym->flags &= ~SYMBOL_CHECK;
1234
1235         if (sym2 && sym_is_choice_value(sym2) &&
1236             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1237                 sym2 = choice;
1238
1239         dep_stack_remove();
1240
1241         return sym2;
1242 }
1243
1244 struct symbol *sym_check_deps(struct symbol *sym)
1245 {
1246         struct symbol *sym2;
1247         struct property *prop;
1248
1249         if (sym->flags & SYMBOL_CHECK) {
1250                 sym_check_print_recursive(sym);
1251                 return sym;
1252         }
1253         if (sym->flags & SYMBOL_CHECKED)
1254                 return NULL;
1255
1256         if (sym_is_choice_value(sym)) {
1257                 struct dep_stack stack;
1258
1259                 /* for choice groups start the check with main choice symbol */
1260                 dep_stack_insert(&stack, sym);
1261                 prop = sym_get_choice_prop(sym);
1262                 sym2 = sym_check_deps(prop_get_symbol(prop));
1263                 dep_stack_remove();
1264         } else if (sym_is_choice(sym)) {
1265                 sym2 = sym_check_choice_deps(sym);
1266         } else {
1267                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1268                 sym2 = sym_check_sym_deps(sym);
1269                 sym->flags &= ~SYMBOL_CHECK;
1270         }
1271
1272         return sym2;
1273 }
1274
1275 struct symbol *prop_get_symbol(struct property *prop)
1276 {
1277         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1278                            prop->expr->type == E_LIST))
1279                 return prop->expr->left.sym;
1280         return NULL;
1281 }
1282
1283 const char *prop_get_type_name(enum prop_type type)
1284 {
1285         switch (type) {
1286         case P_PROMPT:
1287                 return "prompt";
1288         case P_COMMENT:
1289                 return "comment";
1290         case P_MENU:
1291                 return "menu";
1292         case P_DEFAULT:
1293                 return "default";
1294         case P_CHOICE:
1295                 return "choice";
1296         case P_SELECT:
1297                 return "select";
1298         case P_IMPLY:
1299                 return "imply";
1300         case P_RANGE:
1301                 return "range";
1302         case P_SYMBOL:
1303                 return "symbol";
1304         case P_UNKNOWN:
1305                 break;
1306         }
1307         return "unknown";
1308 }