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