config/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 && sym->dir_dep.tri != no)
 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                                 }
 398                         }
 399                 calc_newval:
 400                         if (sym->dir_dep.tri < sym->rev_dep.tri)
 401                                 sym_warn_unmet_dep(sym);
 402                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 403                 }
 404                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 405                         newval.tri = yes;
 406                 break;
 407         case S_STRING:
 408         case S_HEX:
 409         case S_INT:
 410                 if (sym->visible != no && sym_has_value(sym)) {
 411                         newval.val = sym->def[S_DEF_USER].val;
 412                         break;
 413                 }
 414                 prop = sym_get_default_prop(sym);
 415                 if (prop) {
 416                         struct symbol *ds = prop_get_symbol(prop);
 417                         if (ds) {
 418                                 sym->flags |= SYMBOL_WRITE;
 419                                 sym_calc_value(ds);
 420                                 newval.val = ds->curr.val;
 421                         }
 422                 }
 423                 break;
 424         default:
 425                 ;
 426         }
 427
 428         sym->curr = newval;
 429         if (sym_is_choice(sym) && newval.tri == yes)
 430                 sym->curr.val = sym_calc_choice(sym);
 431         sym_validate_range(sym);
 432
 433         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 434                 sym_set_changed(sym);
 435                 if (modules_sym == sym) {
 436                         sym_set_all_changed();
 437                         modules_val = modules_sym->curr.tri;
 438                 }
 439         }
 440
 441         if (sym_is_choice(sym)) {
 442                 struct symbol *choice_sym;
 443
 444                 prop = sym_get_choice_prop(sym);
 445                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
 446                         if ((sym->flags & SYMBOL_WRITE) &&
 447                             choice_sym->visible != no)
 448                                 choice_sym->flags |= SYMBOL_WRITE;
 449                         if (sym->flags & SYMBOL_CHANGED)
 450                                 sym_set_changed(choice_sym);
 451                 }
 452         }
 453
 454         if (sym->flags & SYMBOL_NO_WRITE)
 455                 sym->flags &= ~SYMBOL_WRITE;
 456
 457         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 458                 set_all_choice_values(sym);
 459 }
 460
 461 void sym_clear_all_valid(void)
 462 {
 463         struct symbol *sym;
 464         int i;
 465
 466         for_all_symbols(i, sym)
 467                 sym->flags &= ~SYMBOL_VALID;
 468         sym_add_change_count(1);
 469         sym_calc_value(modules_sym);
 470 }
 471
 472 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 473 {
 474         int type = sym_get_type(sym);
 475
 476         if (sym->visible == no)
 477                 return false;
 478
 479         if (type != S_BOOLEAN && type != S_TRISTATE)
 480                 return false;
 481
 482         if (type == S_BOOLEAN && val == mod)
 483                 return false;
 484         if (sym->visible <= sym->rev_dep.tri)
 485                 return false;
 486         if (sym_is_choice_value(sym) && sym->visible == yes)
 487                 return val == yes;
 488         return val >= sym->rev_dep.tri && val <= sym->visible;
 489 }
 490
 491 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 492 {
 493         tristate oldval = sym_get_tristate_value(sym);
 494
 495         if (oldval != val && !sym_tristate_within_range(sym, val))
 496                 return false;
 497
 498         if (!(sym->flags & SYMBOL_DEF_USER)) {
 499                 sym->flags |= SYMBOL_DEF_USER;
 500                 sym_set_changed(sym);
 501         }
 502         /*
 503          * setting a choice value also resets the new flag of the choice
 504          * symbol and all other choice values.
 505          */
 506         if (sym_is_choice_value(sym) && val == yes) {
 507                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 508                 struct property *prop;
 509                 struct expr *e;
 510
 511                 cs->def[S_DEF_USER].val = sym;
 512                 cs->flags |= SYMBOL_DEF_USER;
 513                 prop = sym_get_choice_prop(cs);
 514                 for (e = prop->expr; e; e = e->left.expr) {
 515                         if (e->right.sym->visible != no)
 516                                 e->right.sym->flags |= SYMBOL_DEF_USER;
 517                 }
 518         }
 519
 520         sym->def[S_DEF_USER].tri = val;
 521         if (oldval != val)
 522                 sym_clear_all_valid();
 523
 524         return true;
 525 }
 526
 527 tristate sym_toggle_tristate_value(struct symbol *sym)
 528 {
 529         tristate oldval, newval;
 530
 531         oldval = newval = sym_get_tristate_value(sym);
 532         do {
 533                 switch (newval) {
 534                 case no:
 535                         newval = mod;
 536                         break;
 537                 case mod:
 538                         newval = yes;
 539                         break;
 540                 case yes:
 541                         newval = no;
 542                         break;
 543                 }
 544                 if (sym_set_tristate_value(sym, newval))
 545                         break;
 546         } while (oldval != newval);
 547         return newval;
 548 }
 549
 550 bool sym_string_valid(struct symbol *sym, const char *str)
 551 {
 552         signed char ch;
 553
 554         switch (sym->type) {
 555         case S_STRING:
 556                 return true;
 557         case S_INT:
 558                 ch = *str++;
 559                 if (ch == '-')
 560                         ch = *str++;
 561                 if (!isdigit(ch))
 562                         return false;
 563                 if (ch == '0' && *str != 0)
 564                         return false;
 565                 while ((ch = *str++)) {
 566                         if (!isdigit(ch))
 567                                 return false;
 568                 }
 569                 return true;
 570         case S_HEX:
 571                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 572                         str += 2;
 573                 ch = *str++;
 574                 do {
 575                         if (!isxdigit(ch))
 576                                 return false;
 577                 } while ((ch = *str++));
 578                 return true;
 579         case S_BOOLEAN:
 580         case S_TRISTATE:
 581                 switch (str[0]) {
 582                 case 'y': case 'Y':
 583                 case 'm': case 'M':
 584                 case 'n': case 'N':
 585                         return true;
 586                 }
 587                 return false;
 588         default:
 589                 return false;
 590         }
 591 }
 592
 593 bool sym_string_within_range(struct symbol *sym, const char *str)
 594 {
 595         struct property *prop;
 596         long long val;
 597
 598         switch (sym->type) {
 599         case S_STRING:
 600                 return sym_string_valid(sym, str);
 601         case S_INT:
 602                 if (!sym_string_valid(sym, str))
 603                         return false;
 604                 prop = sym_get_range_prop(sym);
 605                 if (!prop)
 606                         return true;
 607                 val = strtoll(str, NULL, 10);
 608                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 609                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 610         case S_HEX:
 611                 if (!sym_string_valid(sym, str))
 612                         return false;
 613                 prop = sym_get_range_prop(sym);
 614                 if (!prop)
 615                         return true;
 616                 val = strtoll(str, NULL, 16);
 617                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 618                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 619         case S_BOOLEAN:
 620         case S_TRISTATE:
 621                 switch (str[0]) {
 622                 case 'y': case 'Y':
 623                         return sym_tristate_within_range(sym, yes);
 624                 case 'm': case 'M':
 625                         return sym_tristate_within_range(sym, mod);
 626                 case 'n': case 'N':
 627                         return sym_tristate_within_range(sym, no);
 628                 }
 629                 return false;
 630         default:
 631                 return false;
 632         }
 633 }
 634
 635 bool sym_set_string_value(struct symbol *sym, const char *newval)
 636 {
 637         const char *oldval;
 638         char *val;
 639         int size;
 640
 641         switch (sym->type) {
 642         case S_BOOLEAN:
 643         case S_TRISTATE:
 644                 switch (newval[0]) {
 645                 case 'y': case 'Y':
 646                         return sym_set_tristate_value(sym, yes);
 647                 case 'm': case 'M':
 648                         return sym_set_tristate_value(sym, mod);
 649                 case 'n': case 'N':
 650                         return sym_set_tristate_value(sym, no);
 651                 }
 652                 return false;
 653         default:
 654                 ;
 655         }
 656
 657         if (!sym_string_within_range(sym, newval))
 658                 return false;
 659
 660         if (!(sym->flags & SYMBOL_DEF_USER)) {
 661                 sym->flags |= SYMBOL_DEF_USER;
 662                 sym_set_changed(sym);
 663         }
 664
 665         oldval = sym->def[S_DEF_USER].val;
 666         size = strlen(newval) + 1;
 667         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 668                 size += 2;
 669                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 670                 *val++ = '0';
 671                 *val++ = 'x';
 672         } else if (!oldval || strcmp(oldval, newval))
 673                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 674         else
 675                 return true;
 676
 677         strcpy(val, newval);
 678         free((void *)oldval);
 679         sym_clear_all_valid();
 680
 681         return true;
 682 }
 683
 684 /*
 685  * Find the default value associated to a symbol.
 686  * For tristate symbol handle the modules=n case
 687  * in which case "m" becomes "y".
 688  * If the symbol does not have any default then fallback
 689  * to the fixed default values.
 690  */
 691 const char *sym_get_string_default(struct symbol *sym)
 692 {
 693         struct property *prop;
 694         struct symbol *ds;
 695         const char *str;
 696         tristate val;
 697
 698         sym_calc_visibility(sym);
 699         sym_calc_value(modules_sym);
 700         val = symbol_no.curr.tri;
 701         str = symbol_empty.curr.val;
 702
 703         /* If symbol has a default value look it up */
 704         prop = sym_get_default_prop(sym);
 705         if (prop != NULL) {
 706                 switch (sym->type) {
 707                 case S_BOOLEAN:
 708                 case S_TRISTATE:
 709                         /* The visibility may limit the value from yes => mod */
 710                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 711                         break;
 712                 default:
 713                         /*
 714                          * The following fails to handle the situation
 715                          * where a default value is further limited by
 716                          * the valid range.
 717                          */
 718                         ds = prop_get_symbol(prop);
 719                         if (ds != NULL) {
 720                                 sym_calc_value(ds);
 721                                 str = (const char *)ds->curr.val;
 722                         }
 723                 }
 724         }
 725
 726         /* Handle select statements */
 727         val = EXPR_OR(val, sym->rev_dep.tri);
 728
 729         /* transpose mod to yes if modules are not enabled */
 730         if (val == mod)
 731                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 732                         val = yes;
 733
 734         /* transpose mod to yes if type is bool */
 735         if (sym->type == S_BOOLEAN && val == mod)
 736                 val = yes;
 737
 738         /* adjust the default value if this symbol is implied by another */
 739         if (val < sym->implied.tri)
 740                 val = sym->implied.tri;
 741
 742         switch (sym->type) {
 743         case S_BOOLEAN:
 744         case S_TRISTATE:
 745                 switch (val) {
 746                 case no: return "n";
 747                 case mod: return "m";
 748                 case yes: return "y";
 749                 }
 750         case S_INT:
 751         case S_HEX:
 752                 return str;
 753         case S_STRING:
 754                 return str;
 755         case S_UNKNOWN:
 756                 break;
 757         }
 758         return "";
 759 }
 760
 761 const char *sym_get_string_value(struct symbol *sym)
 762 {
 763         tristate val;
 764
 765         switch (sym->type) {
 766         case S_BOOLEAN:
 767         case S_TRISTATE:
 768                 val = sym_get_tristate_value(sym);
 769                 switch (val) {
 770                 case no:
 771                         return "n";
 772                 case mod:
 773                         sym_calc_value(modules_sym);
 774                         return (modules_sym->curr.tri == no) ? "n" : "m";
 775                 case yes:
 776                         return "y";
 777                 }
 778                 break;
 779         default:
 780                 ;
 781         }
 782         return (const char *)sym->curr.val;
 783 }
 784
 785 bool sym_is_changeable(struct symbol *sym)
 786 {
 787         return sym->visible > sym->rev_dep.tri;
 788 }
 789
 790 static unsigned strhash(const char *s)
 791 {
 792         /* fnv32 hash */
 793         unsigned hash = 2166136261U;
 794         for (; *s; s++)
 795                 hash = (hash ^ *s) * 0x01000193;
 796         return hash;
 797 }
 798
 799 struct symbol *sym_lookup(const char *name, int flags)
 800 {
 801         struct symbol *symbol;
 802         char *new_name;
 803         int hash;
 804
 805         if (name) {
 806                 if (name[0] && !name[1]) {
 807                         switch (name[0]) {
 808                         case 'y': return &symbol_yes;
 809                         case 'm': return &symbol_mod;
 810                         case 'n': return &symbol_no;
 811                         }
 812                 }
 813                 hash = strhash(name) % SYMBOL_HASHSIZE;
 814
 815                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 816                         if (symbol->name &&
 817                             !strcmp(symbol->name, name) &&
 818                             (flags ? symbol->flags & flags
 819                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 820                                 return symbol;
 821                 }
 822                 new_name = xstrdup(name);
 823         } else {
 824                 new_name = NULL;
 825                 hash = 0;
 826         }
 827
 828         symbol = xmalloc(sizeof(*symbol));
 829         memset(symbol, 0, sizeof(*symbol));
 830         symbol->name = new_name;
 831         symbol->type = S_UNKNOWN;
 832         symbol->flags |= flags;
 833
 834         symbol->next = symbol_hash[hash];
 835         symbol_hash[hash] = symbol;
 836
 837         return symbol;
 838 }
 839
 840 struct symbol *sym_find(const char *name)
 841 {
 842         struct symbol *symbol = NULL;
 843         int hash = 0;
 844
 845         if (!name)
 846                 return NULL;
 847
 848         if (name[0] && !name[1]) {
 849                 switch (name[0]) {
 850                 case 'y': return &symbol_yes;
 851                 case 'm': return &symbol_mod;
 852                 case 'n': return &symbol_no;
 853                 }
 854         }
 855         hash = strhash(name) % SYMBOL_HASHSIZE;
 856
 857         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 858                 if (symbol->name &&
 859                     !strcmp(symbol->name, name) &&
 860                     !(symbol->flags & SYMBOL_CONST))
 861                                 break;
 862         }
 863
 864         return symbol;
 865 }
 866
 867 const char *sym_escape_string_value(const char *in)
 868 {
 869         const char *p;
 870         size_t reslen;
 871         char *res;
 872         size_t l;
 873
 874         reslen = strlen(in) + strlen("\"\"") + 1;
 875
 876         p = in;
 877         for (;;) {
 878                 l = strcspn(p, "\"\\");
 879                 p += l;
 880
 881                 if (p[0] == '\0')
 882                         break;
 883
 884                 reslen++;
 885                 p++;
 886         }
 887
 888         res = xmalloc(reslen);
 889         res[0] = '\0';
 890
 891         strcat(res, "\"");
 892
 893         p = in;
 894         for (;;) {
 895                 l = strcspn(p, "\"\\");
 896                 strncat(res, p, l);
 897                 p += l;
 898
 899                 if (p[0] == '\0')
 900                         break;
 901
 902                 strcat(res, "\\");
 903                 strncat(res, p++, 1);
 904         }
 905
 906         strcat(res, "\"");
 907         return res;
 908 }
 909
 910 struct sym_match {
 911         struct symbol   *sym;
 912         off_t           so, eo;
 913 };
 914
 915 /* Compare matched symbols as thus:
 916  * - first, symbols that match exactly
 917  * - then, alphabetical sort
 918  */
 919 static int sym_rel_comp(const void *sym1, const void *sym2)
 920 {
 921         const struct sym_match *s1 = sym1;
 922         const struct sym_match *s2 = sym2;
 923         int exact1, exact2;
 924
 925         /* Exact match:
 926          * - if matched length on symbol s1 is the length of that symbol,
 927          *   then this symbol should come first;
 928          * - if matched length on symbol s2 is the length of that symbol,
 929          *   then this symbol should come first.
 930          * Note: since the search can be a regexp, both symbols may match
 931          * exactly; if this is the case, we can't decide which comes first,
 932          * and we fallback to sorting alphabetically.
 933          */
 934         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 935         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 936         if (exact1 && !exact2)
 937                 return -1;
 938         if (!exact1 && exact2)
 939                 return 1;
 940
 941         /* As a fallback, sort symbols alphabetically */
 942         return strcmp(s1->sym->name, s2->sym->name);
 943 }
 944
 945 struct symbol **sym_re_search(const char *pattern)
 946 {
 947         struct symbol *sym, **sym_arr = NULL;
 948         struct sym_match *sym_match_arr = NULL;
 949         int i, cnt, size;
 950         regex_t re;
 951         regmatch_t match[1];
 952
 953         cnt = size = 0;
 954         /* Skip if empty */
 955         if (strlen(pattern) == 0)
 956                 return NULL;
 957         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 958                 return NULL;
 959
 960         for_all_symbols(i, sym) {
 961                 if (sym->flags & SYMBOL_CONST || !sym->name)
 962                         continue;
 963                 if (regexec(&re, sym->name, 1, match, 0))
 964                         continue;
 965                 if (cnt >= size) {
 966                         void *tmp;
 967                         size += 16;
 968                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 969                         if (!tmp)
 970                                 goto sym_re_search_free;
 971                         sym_match_arr = tmp;
 972                 }
 973                 sym_calc_value(sym);
 974                 /* As regexec returned 0, we know we have a match, so
 975                  * we can use match[0].rm_[se]o without further checks
 976                  */
 977                 sym_match_arr[cnt].so = match[0].rm_so;
 978                 sym_match_arr[cnt].eo = match[0].rm_eo;
 979                 sym_match_arr[cnt++].sym = sym;
 980         }
 981         if (sym_match_arr) {
 982                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 983                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 984                 if (!sym_arr)
 985                         goto sym_re_search_free;
 986                 for (i = 0; i < cnt; i++)
 987                         sym_arr[i] = sym_match_arr[i].sym;
 988                 sym_arr[cnt] = NULL;
 989         }
 990 sym_re_search_free:
 991         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
 992         free(sym_match_arr);
 993         regfree(&re);
 994
 995         return sym_arr;
 996 }
 997
 998 /*
 999  * When we check for recursive dependencies we use a stack to save
1000  * current state so we can print out relevant info to user.
1001  * The entries are located on the call stack so no need to free memory.
1002  * Note insert() remove() must always match to properly clear the stack.
1003  */
1004 static struct dep_stack {
1005         struct dep_stack *prev, *next;
1006         struct symbol *sym;
1007         struct property *prop;
1008         struct expr **expr;
1009 } *check_top;
1010
1011 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1012 {
1013         memset(stack, 0, sizeof(*stack));
1014         if (check_top)
1015                 check_top->next = stack;
1016         stack->prev = check_top;
1017         stack->sym = sym;
1018         check_top = stack;
1019 }
1020
1021 static void dep_stack_remove(void)
1022 {
1023         check_top = check_top->prev;
1024         if (check_top)
1025                 check_top->next = NULL;
1026 }
1027
1028 /*
1029  * Called when we have detected a recursive dependency.
1030  * check_top point to the top of the stact so we use
1031  * the ->prev pointer to locate the bottom of the stack.
1032  */
1033 static void sym_check_print_recursive(struct symbol *last_sym)
1034 {
1035         struct dep_stack *stack;
1036         struct symbol *sym, *next_sym;
1037         struct menu *menu = NULL;
1038         struct property *prop;
1039         struct dep_stack cv_stack;
1040
1041         if (sym_is_choice_value(last_sym)) {
1042                 dep_stack_insert(&cv_stack, last_sym);
1043                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1044         }
1045
1046         for (stack = check_top; stack != NULL; stack = stack->prev)
1047                 if (stack->sym == last_sym)
1048                         break;
1049         if (!stack) {
1050                 fprintf(stderr, "unexpected recursive dependency error\n");
1051                 return;
1052         }
1053
1054         for (; stack; stack = stack->next) {
1055                 sym = stack->sym;
1056                 next_sym = stack->next ? stack->next->sym : last_sym;
1057                 prop = stack->prop;
1058                 if (prop == NULL)
1059                         prop = stack->sym->prop;
1060
1061                 /* for choice values find the menu entry (used below) */
1062                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1063                         for (prop = sym->prop; prop; prop = prop->next) {
1064                                 menu = prop->menu;
1065                                 if (prop->menu)
1066                                         break;
1067                         }
1068                 }
1069                 if (stack->sym == last_sym)
1070                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1071                                 prop->file->name, prop->lineno);
1072
1073                 if (sym_is_choice(sym)) {
1074                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1075                                 menu->file->name, menu->lineno,
1076                                 sym->name ? sym->name : "<choice>",
1077                                 next_sym->name ? next_sym->name : "<choice>");
1078                 } else if (sym_is_choice_value(sym)) {
1079                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1080                                 menu->file->name, menu->lineno,
1081                                 sym->name ? sym->name : "<choice>",
1082                                 next_sym->name ? next_sym->name : "<choice>");
1083                 } else if (stack->expr == &sym->dir_dep.expr) {
1084                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1085                                 prop->file->name, prop->lineno,
1086                                 sym->name ? sym->name : "<choice>",
1087                                 next_sym->name ? next_sym->name : "<choice>");
1088                 } else if (stack->expr == &sym->rev_dep.expr) {
1089                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1090                                 prop->file->name, prop->lineno,
1091                                 sym->name ? sym->name : "<choice>",
1092                                 next_sym->name ? next_sym->name : "<choice>");
1093                 } else if (stack->expr == &sym->implied.expr) {
1094                         fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1095                                 prop->file->name, prop->lineno,
1096                                 sym->name ? sym->name : "<choice>",
1097                                 next_sym->name ? next_sym->name : "<choice>");
1098                 } else if (stack->expr) {
1099                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1100                                 prop->file->name, prop->lineno,
1101                                 sym->name ? sym->name : "<choice>",
1102                                 prop_get_type_name(prop->type),
1103                                 next_sym->name ? next_sym->name : "<choice>");
1104                 } else {
1105                         fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1106                                 prop->file->name, prop->lineno,
1107                                 sym->name ? sym->name : "<choice>",
1108                                 prop_get_type_name(prop->type),
1109                                 next_sym->name ? next_sym->name : "<choice>");
1110                 }
1111         }
1112
1113         fprintf(stderr,
1114                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1115                 "subsection \"Kconfig recursive dependency limitations\"\n"
1116                 "\n");
1117
1118         if (check_top == &cv_stack)
1119                 dep_stack_remove();
1120 }
1121
1122 static struct symbol *sym_check_expr_deps(struct expr *e)
1123 {
1124         struct symbol *sym;
1125
1126         if (!e)
1127                 return NULL;
1128         switch (e->type) {
1129         case E_OR:
1130         case E_AND:
1131                 sym = sym_check_expr_deps(e->left.expr);
1132                 if (sym)
1133                         return sym;
1134                 return sym_check_expr_deps(e->right.expr);
1135         case E_NOT:
1136                 return sym_check_expr_deps(e->left.expr);
1137         case E_EQUAL:
1138         case E_GEQ:
1139         case E_GTH:
1140         case E_LEQ:
1141         case E_LTH:
1142         case E_UNEQUAL:
1143                 sym = sym_check_deps(e->left.sym);
1144                 if (sym)
1145                         return sym;
1146                 return sym_check_deps(e->right.sym);
1147         case E_SYMBOL:
1148                 return sym_check_deps(e->left.sym);
1149         default:
1150                 break;
1151         }
1152         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1153         return NULL;
1154 }
1155
1156 /* return NULL when dependencies are OK */
1157 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1158 {
1159         struct symbol *sym2;
1160         struct property *prop;
1161         struct dep_stack stack;
1162
1163         dep_stack_insert(&stack, sym);
1164
1165         stack.expr = &sym->dir_dep.expr;
1166         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1167         if (sym2)
1168                 goto out;
1169
1170         stack.expr = &sym->rev_dep.expr;
1171         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1172         if (sym2)
1173                 goto out;
1174
1175         stack.expr = &sym->implied.expr;
1176         sym2 = sym_check_expr_deps(sym->implied.expr);
1177         if (sym2)
1178                 goto out;
1179
1180         stack.expr = NULL;
1181
1182         for (prop = sym->prop; prop; prop = prop->next) {
1183                 if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1184                     prop->type == P_IMPLY)
1185                         continue;
1186                 stack.prop = prop;
1187                 sym2 = sym_check_expr_deps(prop->visible.expr);
1188                 if (sym2)
1189                         break;
1190                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1191                         continue;
1192                 stack.expr = &prop->expr;
1193                 sym2 = sym_check_expr_deps(prop->expr);
1194                 if (sym2)
1195                         break;
1196                 stack.expr = NULL;
1197         }
1198
1199 out:
1200         dep_stack_remove();
1201
1202         return sym2;
1203 }
1204
1205 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1206 {
1207         struct symbol *sym, *sym2;
1208         struct property *prop;
1209         struct expr *e;
1210         struct dep_stack stack;
1211
1212         dep_stack_insert(&stack, choice);
1213
1214         prop = sym_get_choice_prop(choice);
1215         expr_list_for_each_sym(prop->expr, e, sym)
1216                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1217
1218         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1219         sym2 = sym_check_sym_deps(choice);
1220         choice->flags &= ~SYMBOL_CHECK;
1221         if (sym2)
1222                 goto out;
1223
1224         expr_list_for_each_sym(prop->expr, e, sym) {
1225                 sym2 = sym_check_sym_deps(sym);
1226                 if (sym2)
1227                         break;
1228         }
1229 out:
1230         expr_list_for_each_sym(prop->expr, e, sym)
1231                 sym->flags &= ~SYMBOL_CHECK;
1232
1233         if (sym2 && sym_is_choice_value(sym2) &&
1234             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1235                 sym2 = choice;
1236
1237         dep_stack_remove();
1238
1239         return sym2;
1240 }
1241
1242 struct symbol *sym_check_deps(struct symbol *sym)
1243 {
1244         struct symbol *sym2;
1245         struct property *prop;
1246
1247         if (sym->flags & SYMBOL_CHECK) {
1248                 sym_check_print_recursive(sym);
1249                 return sym;
1250         }
1251         if (sym->flags & SYMBOL_CHECKED)
1252                 return NULL;
1253
1254         if (sym_is_choice_value(sym)) {
1255                 struct dep_stack stack;
1256
1257                 /* for choice groups start the check with main choice symbol */
1258                 dep_stack_insert(&stack, sym);
1259                 prop = sym_get_choice_prop(sym);
1260                 sym2 = sym_check_deps(prop_get_symbol(prop));
1261                 dep_stack_remove();
1262         } else if (sym_is_choice(sym)) {
1263                 sym2 = sym_check_choice_deps(sym);
1264         } else {
1265                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1266                 sym2 = sym_check_sym_deps(sym);
1267                 sym->flags &= ~SYMBOL_CHECK;
1268         }
1269
1270         return sym2;
1271 }
1272
1273 struct symbol *prop_get_symbol(struct property *prop)
1274 {
1275         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1276                            prop->expr->type == E_LIST))
1277                 return prop->expr->left.sym;
1278         return NULL;
1279 }
1280
1281 const char *prop_get_type_name(enum prop_type type)
1282 {
1283         switch (type) {
1284         case P_PROMPT:
1285                 return "prompt";
1286         case P_COMMENT:
1287                 return "comment";
1288         case P_MENU:
1289                 return "menu";
1290         case P_DEFAULT:
1291                 return "default";
1292         case P_CHOICE:
1293                 return "choice";
1294         case P_SELECT:
1295                 return "select";
1296         case P_IMPLY:
1297                 return "imply";
1298         case P_RANGE:
1299                 return "range";
1300         case P_SYMBOL:
1301                 return "symbol";
1302         case P_UNKNOWN:
1303                 break;
1304         }
1305         return "unknown";
1306 }