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 <hash.h>
  13 #include <xalloc.h>
  14 #include "internal.h"
  15 #include "lkc.h"
  16
  17 struct symbol symbol_yes = {
  18         .name = "y",
  19         .type = S_TRISTATE,
  20         .curr = { "y", yes },
  21         .menus = LIST_HEAD_INIT(symbol_yes.menus),
  22         .flags = SYMBOL_CONST|SYMBOL_VALID,
  23 };
  24
  25 struct symbol symbol_mod = {
  26         .name = "m",
  27         .type = S_TRISTATE,
  28         .curr = { "m", mod },
  29         .menus = LIST_HEAD_INIT(symbol_mod.menus),
  30         .flags = SYMBOL_CONST|SYMBOL_VALID,
  31 };
  32
  33 struct symbol symbol_no = {
  34         .name = "n",
  35         .type = S_TRISTATE,
  36         .curr = { "n", no },
  37         .menus = LIST_HEAD_INIT(symbol_no.menus),
  38         .flags = SYMBOL_CONST|SYMBOL_VALID,
  39 };
  40
  41 struct symbol *modules_sym;
  42 static tristate modules_val;
  43 static int sym_warnings;
  44
  45 enum symbol_type sym_get_type(const struct symbol *sym)
  46 {
  47         enum symbol_type type = sym->type;
  48
  49         if (type == S_TRISTATE && modules_val == no)
  50                 type = S_BOOLEAN;
  51         return type;
  52 }
  53
  54 const char *sym_type_name(enum symbol_type type)
  55 {
  56         switch (type) {
  57         case S_BOOLEAN:
  58                 return "bool";
  59         case S_TRISTATE:
  60                 return "tristate";
  61         case S_INT:
  62                 return "integer";
  63         case S_HEX:
  64                 return "hex";
  65         case S_STRING:
  66                 return "string";
  67         case S_UNKNOWN:
  68                 return "unknown";
  69         }
  70         return "???";
  71 }
  72
  73 /**
  74  * sym_get_prompt_menu - get the menu entry with a prompt
  75  *
  76  * @sym: a symbol pointer
  77  *
  78  * Return: the menu entry with a prompt.
  79  */
  80 struct menu *sym_get_prompt_menu(const struct symbol *sym)
  81 {
  82         struct menu *m;
  83
  84         list_for_each_entry(m, &sym->menus, link)
  85                 if (m->prompt)
  86                         return m;
  87
  88         return NULL;
  89 }
  90
  91 /**
  92  * sym_get_choice_menu - get the parent choice menu if present
  93  *
  94  * @sym: a symbol pointer
  95  *
  96  * Return: a choice menu if this function is called against a choice member.
  97  */
  98 struct menu *sym_get_choice_menu(const struct symbol *sym)
  99 {
 100         struct menu *menu = NULL;
 101
 102         /*
 103          * Choice members must have a prompt. Find a menu entry with a prompt,
 104          * and assume it resides inside a choice block.
 105          */
 106         menu = sym_get_prompt_menu(sym);
 107         if (!menu)
 108                 return NULL;
 109
 110         do {
 111                 menu = menu->parent;
 112         } while (menu && !menu->sym);
 113
 114         if (menu && menu->sym && sym_is_choice(menu->sym))
 115                 return menu;
 116
 117         return NULL;
 118 }
 119
 120 static struct property *sym_get_default_prop(struct symbol *sym)
 121 {
 122         struct property *prop;
 123
 124         for_all_defaults(sym, prop) {
 125                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 126                 if (prop->visible.tri != no)
 127                         return prop;
 128         }
 129         return NULL;
 130 }
 131
 132 struct property *sym_get_range_prop(struct symbol *sym)
 133 {
 134         struct property *prop;
 135
 136         for_all_properties(sym, prop, P_RANGE) {
 137                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 138                 if (prop->visible.tri != no)
 139                         return prop;
 140         }
 141         return NULL;
 142 }
 143
 144 static long long sym_get_range_val(struct symbol *sym, int base)
 145 {
 146         sym_calc_value(sym);
 147         switch (sym->type) {
 148         case S_INT:
 149                 base = 10;
 150                 break;
 151         case S_HEX:
 152                 base = 16;
 153                 break;
 154         default:
 155                 break;
 156         }
 157         return strtoll(sym->curr.val, NULL, base);
 158 }
 159
 160 static void sym_validate_range(struct symbol *sym)
 161 {
 162         struct property *prop;
 163         struct symbol *range_sym;
 164         int base;
 165         long long val, val2;
 166
 167         switch (sym->type) {
 168         case S_INT:
 169                 base = 10;
 170                 break;
 171         case S_HEX:
 172                 base = 16;
 173                 break;
 174         default:
 175                 return;
 176         }
 177         prop = sym_get_range_prop(sym);
 178         if (!prop)
 179                 return;
 180         val = strtoll(sym->curr.val, NULL, base);
 181         range_sym = prop->expr->left.sym;
 182         val2 = sym_get_range_val(range_sym, base);
 183         if (val >= val2) {
 184                 range_sym = prop->expr->right.sym;
 185                 val2 = sym_get_range_val(range_sym, base);
 186                 if (val <= val2)
 187                         return;
 188         }
 189         sym->curr.val = range_sym->curr.val;
 190 }
 191
 192 static void sym_set_changed(struct symbol *sym)
 193 {
 194         struct menu *menu;
 195
 196         list_for_each_entry(menu, &sym->menus, link)
 197                 menu->flags |= MENU_CHANGED;
 198 }
 199
 200 static void sym_set_all_changed(void)
 201 {
 202         struct symbol *sym;
 203
 204         for_all_symbols(sym)
 205                 sym_set_changed(sym);
 206 }
 207
 208 static void sym_calc_visibility(struct symbol *sym)
 209 {
 210         struct property *prop;
 211         tristate tri;
 212
 213         /* any prompt visible? */
 214         tri = no;
 215         for_all_prompts(sym, prop) {
 216                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 217                 tri = EXPR_OR(tri, prop->visible.tri);
 218         }
 219         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 220                 tri = yes;
 221         if (sym->visible != tri) {
 222                 sym->visible = tri;
 223                 sym_set_changed(sym);
 224         }
 225         if (sym_is_choice_value(sym))
 226                 return;
 227         /* defaulting to "yes" if no explicit "depends on" are given */
 228         tri = yes;
 229         if (sym->dir_dep.expr)
 230                 tri = expr_calc_value(sym->dir_dep.expr);
 231         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 232                 tri = yes;
 233         if (sym->dir_dep.tri != tri) {
 234                 sym->dir_dep.tri = tri;
 235                 sym_set_changed(sym);
 236         }
 237         tri = no;
 238         if (sym->rev_dep.expr)
 239                 tri = expr_calc_value(sym->rev_dep.expr);
 240         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 241                 tri = yes;
 242         if (sym->rev_dep.tri != tri) {
 243                 sym->rev_dep.tri = tri;
 244                 sym_set_changed(sym);
 245         }
 246         tri = no;
 247         if (sym->implied.expr)
 248                 tri = expr_calc_value(sym->implied.expr);
 249         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 250                 tri = yes;
 251         if (sym->implied.tri != tri) {
 252                 sym->implied.tri = tri;
 253                 sym_set_changed(sym);
 254         }
 255 }
 256
 257 /*
 258  * Find the default symbol for a choice.
 259  * First try the default values for the choice symbol
 260  * Next locate the first visible choice value
 261  * Return NULL if none was found
 262  */
 263 struct symbol *sym_choice_default(struct menu *choice)
 264 {
 265         struct menu *menu;
 266         struct symbol *def_sym;
 267         struct property *prop;
 268
 269         /* any of the defaults visible? */
 270         for_all_defaults(choice->sym, prop) {
 271                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 272                 if (prop->visible.tri == no)
 273                         continue;
 274                 def_sym = prop_get_symbol(prop);
 275                 if (def_sym->visible != no)
 276                         return def_sym;
 277         }
 278
 279         /* just get the first visible value */
 280         menu_for_each_sub_entry(menu, choice)
 281                 if (menu->sym && menu->sym->visible != no)
 282                         return menu->sym;
 283
 284         /* failed to locate any defaults */
 285         return NULL;
 286 }
 287
 288 /*
 289  * sym_calc_choice - calculate symbol values in a choice
 290  *
 291  * @choice: a menu of the choice
 292  *
 293  * Return: a chosen symbol
 294  */
 295 struct symbol *sym_calc_choice(struct menu *choice)
 296 {
 297         struct symbol *res = NULL;
 298         struct symbol *sym;
 299         struct menu *menu;
 300
 301         /* Traverse the list of choice members in the priority order. */
 302         list_for_each_entry(sym, &choice->choice_members, choice_link) {
 303                 sym_calc_visibility(sym);
 304                 if (sym->visible == no)
 305                         continue;
 306
 307                 /* The first visible symble with the user value 'y'. */
 308                 if (sym_has_value(sym) && sym->def[S_DEF_USER].tri == yes) {
 309                         res = sym;
 310                         break;
 311                 }
 312         }
 313
 314         /*
 315          * If 'y' is not found in the user input, use the default, unless it is
 316          * explicitly set to 'n'.
 317          */
 318         if (!res) {
 319                 res = sym_choice_default(choice);
 320                 if (res && sym_has_value(res) && res->def[S_DEF_USER].tri == no)
 321                         res = NULL;
 322         }
 323
 324         /* Still not found. Pick up the first visible, user-unspecified symbol. */
 325         if (!res) {
 326                 menu_for_each_sub_entry(menu, choice) {
 327                         sym = menu->sym;
 328
 329                         if (!sym || sym->visible == no || sym_has_value(sym))
 330                                 continue;
 331
 332                         res = sym;
 333                         break;
 334                 }
 335         }
 336
 337         /*
 338          * Still not found. Traverse the linked list in the _reverse_ order to
 339          * pick up the least prioritized 'n'.
 340          */
 341         if (!res) {
 342                 list_for_each_entry_reverse(sym, &choice->choice_members,
 343                                             choice_link) {
 344                         if (sym->visible == no)
 345                                 continue;
 346
 347                         res = sym;
 348                         break;
 349                 }
 350         }
 351
 352         menu_for_each_sub_entry(menu, choice) {
 353                 tristate val;
 354
 355                 sym = menu->sym;
 356
 357                 if (!sym || sym->visible == no)
 358                         continue;
 359
 360                 val = sym == res ? yes : no;
 361
 362                 if (sym->curr.tri != val)
 363                         sym_set_changed(sym);
 364
 365                 sym->curr.tri = val;
 366                 sym->flags |= SYMBOL_VALID | SYMBOL_WRITE;
 367         }
 368
 369         return res;
 370 }
 371
 372 static void sym_warn_unmet_dep(const struct symbol *sym)
 373 {
 374         struct gstr gs = str_new();
 375
 376         str_printf(&gs,
 377                    "\nWARNING: unmet direct dependencies detected for %s\n",
 378                    sym->name);
 379         str_printf(&gs,
 380                    "  Depends on [%c]: ",
 381                    sym->dir_dep.tri == mod ? 'm' : 'n');
 382         expr_gstr_print(sym->dir_dep.expr, &gs);
 383         str_printf(&gs, "\n");
 384
 385         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 386                                "  Selected by [y]:\n");
 387         expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 388                                "  Selected by [m]:\n");
 389
 390         fputs(str_get(&gs), stderr);
 391         sym_warnings++;
 392 }
 393
 394 bool sym_dep_errors(void)
 395 {
 396         if (sym_warnings)
 397                 return getenv("KCONFIG_WERROR");
 398         return false;
 399 }
 400
 401 void sym_calc_value(struct symbol *sym)
 402 {
 403         struct symbol_value newval, oldval;
 404         struct property *prop;
 405         struct menu *choice_menu;
 406
 407         if (!sym)
 408                 return;
 409
 410         if (sym->flags & SYMBOL_VALID)
 411                 return;
 412
 413         sym->flags |= SYMBOL_VALID;
 414
 415         oldval = sym->curr;
 416
 417         newval.tri = no;
 418
 419         switch (sym->type) {
 420         case S_INT:
 421                 newval.val = "0";
 422                 break;
 423         case S_HEX:
 424                 newval.val = "0x0";
 425                 break;
 426         case S_STRING:
 427                 newval.val = "";
 428                 break;
 429         case S_BOOLEAN:
 430         case S_TRISTATE:
 431                 newval.val = "n";
 432                 break;
 433         default:
 434                 sym->curr.val = sym->name;
 435                 sym->curr.tri = no;
 436                 return;
 437         }
 438         sym->flags &= ~SYMBOL_WRITE;
 439
 440         sym_calc_visibility(sym);
 441
 442         if (sym->visible != no)
 443                 sym->flags |= SYMBOL_WRITE;
 444
 445         /* set default if recursively called */
 446         sym->curr = newval;
 447
 448         switch (sym_get_type(sym)) {
 449         case S_BOOLEAN:
 450         case S_TRISTATE:
 451                 choice_menu = sym_get_choice_menu(sym);
 452
 453                 if (choice_menu) {
 454                         sym_calc_choice(choice_menu);
 455                         newval.tri = sym->curr.tri;
 456                 } else {
 457                         if (sym->visible != no) {
 458                                 /* if the symbol is visible use the user value
 459                                  * if available, otherwise try the default value
 460                                  */
 461                                 if (sym_has_value(sym)) {
 462                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 463                                                               sym->visible);
 464                                         goto calc_newval;
 465                                 }
 466                         }
 467                         if (sym->rev_dep.tri != no)
 468                                 sym->flags |= SYMBOL_WRITE;
 469                         if (!sym_is_choice(sym)) {
 470                                 prop = sym_get_default_prop(sym);
 471                                 if (prop) {
 472                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 473                                                               prop->visible.tri);
 474                                         if (newval.tri != no)
 475                                                 sym->flags |= SYMBOL_WRITE;
 476                                 }
 477                                 if (sym->implied.tri != no) {
 478                                         sym->flags |= SYMBOL_WRITE;
 479                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 480                                         newval.tri = EXPR_AND(newval.tri,
 481                                                               sym->dir_dep.tri);
 482                                 }
 483                         }
 484                 calc_newval:
 485                         if (sym->dir_dep.tri < sym->rev_dep.tri)
 486                                 sym_warn_unmet_dep(sym);
 487                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 488                 }
 489                 if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 490                         newval.tri = yes;
 491                 break;
 492         case S_STRING:
 493         case S_HEX:
 494         case S_INT:
 495                 if (sym->visible != no && sym_has_value(sym)) {
 496                         newval.val = sym->def[S_DEF_USER].val;
 497                         break;
 498                 }
 499                 prop = sym_get_default_prop(sym);
 500                 if (prop) {
 501                         struct symbol *ds = prop_get_symbol(prop);
 502                         if (ds) {
 503                                 sym->flags |= SYMBOL_WRITE;
 504                                 sym_calc_value(ds);
 505                                 newval.val = ds->curr.val;
 506                         }
 507                 }
 508                 break;
 509         default:
 510                 ;
 511         }
 512
 513         sym->curr = newval;
 514         sym_validate_range(sym);
 515
 516         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 517                 sym_set_changed(sym);
 518                 if (modules_sym == sym) {
 519                         sym_set_all_changed();
 520                         modules_val = modules_sym->curr.tri;
 521                 }
 522         }
 523
 524         if (sym_is_choice(sym))
 525                 sym->flags &= ~SYMBOL_WRITE;
 526 }
 527
 528 void sym_clear_all_valid(void)
 529 {
 530         struct symbol *sym;
 531
 532         for_all_symbols(sym)
 533                 sym->flags &= ~SYMBOL_VALID;
 534         expr_invalidate_all();
 535         conf_set_changed(true);
 536         sym_calc_value(modules_sym);
 537 }
 538
 539 bool sym_tristate_within_range(const struct symbol *sym, tristate val)
 540 {
 541         int type = sym_get_type(sym);
 542
 543         if (sym->visible == no)
 544                 return false;
 545
 546         if (type != S_BOOLEAN && type != S_TRISTATE)
 547                 return false;
 548
 549         if (type == S_BOOLEAN && val == mod)
 550                 return false;
 551         if (sym->visible <= sym->rev_dep.tri)
 552                 return false;
 553         return val >= sym->rev_dep.tri && val <= sym->visible;
 554 }
 555
 556 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 557 {
 558         tristate oldval = sym_get_tristate_value(sym);
 559
 560         if (!sym_tristate_within_range(sym, val))
 561                 return false;
 562
 563         if (!(sym->flags & SYMBOL_DEF_USER) || sym->def[S_DEF_USER].tri != val) {
 564                 sym->def[S_DEF_USER].tri = val;
 565                 sym->flags |= SYMBOL_DEF_USER;
 566                 sym_set_changed(sym);
 567         }
 568
 569         if (oldval != val)
 570                 sym_clear_all_valid();
 571
 572         return true;
 573 }
 574
 575 /**
 576  * choice_set_value - set the user input to a choice
 577  *
 578  * @choice: menu entry for the choice
 579  * @sym: selected symbol
 580  */
 581 void choice_set_value(struct menu *choice, struct symbol *sym)
 582 {
 583         struct menu *menu;
 584         bool changed = false;
 585
 586         menu_for_each_sub_entry(menu, choice) {
 587                 tristate val;
 588
 589                 if (!menu->sym)
 590                         continue;
 591
 592                 if (menu->sym->visible == no)
 593                         continue;
 594
 595                 val = menu->sym == sym ? yes : no;
 596
 597                 if (menu->sym->curr.tri != val)
 598                         changed = true;
 599
 600                 menu->sym->def[S_DEF_USER].tri = val;
 601                 menu->sym->flags |= SYMBOL_DEF_USER;
 602
 603                 /*
 604                  * Now, the user has explicitly enabled or disabled this symbol,
 605                  * it should be given the highest priority. We are possibly
 606                  * setting multiple symbols to 'n', where the first symbol is
 607                  * given the least prioritized 'n'. This works well when the
 608                  * choice block ends up with selecting 'n' symbol.
 609                  * (see sym_calc_choice())
 610                  */
 611                 list_move(&menu->sym->choice_link, &choice->choice_members);
 612         }
 613
 614         if (changed)
 615                 sym_clear_all_valid();
 616 }
 617
 618 tristate sym_toggle_tristate_value(struct symbol *sym)
 619 {
 620         struct menu *choice;
 621         tristate oldval, newval;
 622
 623         choice = sym_get_choice_menu(sym);
 624         if (choice) {
 625                 choice_set_value(choice, sym);
 626                 return yes;
 627         }
 628
 629         oldval = newval = sym_get_tristate_value(sym);
 630         do {
 631                 switch (newval) {
 632                 case no:
 633                         newval = mod;
 634                         break;
 635                 case mod:
 636                         newval = yes;
 637                         break;
 638                 case yes:
 639                         newval = no;
 640                         break;
 641                 }
 642                 if (sym_set_tristate_value(sym, newval))
 643                         break;
 644         } while (oldval != newval);
 645         return newval;
 646 }
 647
 648 bool sym_string_valid(struct symbol *sym, const char *str)
 649 {
 650         signed char ch;
 651
 652         switch (sym->type) {
 653         case S_STRING:
 654                 return true;
 655         case S_INT:
 656                 ch = *str++;
 657                 if (ch == '-')
 658                         ch = *str++;
 659                 if (!isdigit(ch))
 660                         return false;
 661                 if (ch == '0' && *str != 0)
 662                         return false;
 663                 while ((ch = *str++)) {
 664                         if (!isdigit(ch))
 665                                 return false;
 666                 }
 667                 return true;
 668         case S_HEX:
 669                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 670                         str += 2;
 671                 ch = *str++;
 672                 do {
 673                         if (!isxdigit(ch))
 674                                 return false;
 675                 } while ((ch = *str++));
 676                 return true;
 677         case S_BOOLEAN:
 678         case S_TRISTATE:
 679                 switch (str[0]) {
 680                 case 'y': case 'Y':
 681                 case 'm': case 'M':
 682                 case 'n': case 'N':
 683                         return true;
 684                 }
 685                 return false;
 686         default:
 687                 return false;
 688         }
 689 }
 690
 691 bool sym_string_within_range(struct symbol *sym, const char *str)
 692 {
 693         struct property *prop;
 694         long long val;
 695
 696         switch (sym->type) {
 697         case S_STRING:
 698                 return sym_string_valid(sym, str);
 699         case S_INT:
 700                 if (!sym_string_valid(sym, str))
 701                         return false;
 702                 prop = sym_get_range_prop(sym);
 703                 if (!prop)
 704                         return true;
 705                 val = strtoll(str, NULL, 10);
 706                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 707                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 708         case S_HEX:
 709                 if (!sym_string_valid(sym, str))
 710                         return false;
 711                 prop = sym_get_range_prop(sym);
 712                 if (!prop)
 713                         return true;
 714                 val = strtoll(str, NULL, 16);
 715                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 716                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 717         case S_BOOLEAN:
 718         case S_TRISTATE:
 719                 switch (str[0]) {
 720                 case 'y': case 'Y':
 721                         return sym_tristate_within_range(sym, yes);
 722                 case 'm': case 'M':
 723                         return sym_tristate_within_range(sym, mod);
 724                 case 'n': case 'N':
 725                         return sym_tristate_within_range(sym, no);
 726                 }
 727                 return false;
 728         default:
 729                 return false;
 730         }
 731 }
 732
 733 bool sym_set_string_value(struct symbol *sym, const char *newval)
 734 {
 735         const char *oldval;
 736         char *val;
 737         int size;
 738
 739         switch (sym->type) {
 740         case S_BOOLEAN:
 741         case S_TRISTATE:
 742                 switch (newval[0]) {
 743                 case 'y': case 'Y':
 744                         return sym_set_tristate_value(sym, yes);
 745                 case 'm': case 'M':
 746                         return sym_set_tristate_value(sym, mod);
 747                 case 'n': case 'N':
 748                         return sym_set_tristate_value(sym, no);
 749                 }
 750                 return false;
 751         default:
 752                 ;
 753         }
 754
 755         if (!sym_string_within_range(sym, newval))
 756                 return false;
 757
 758         if (!(sym->flags & SYMBOL_DEF_USER)) {
 759                 sym->flags |= SYMBOL_DEF_USER;
 760                 sym_set_changed(sym);
 761         }
 762
 763         oldval = sym->def[S_DEF_USER].val;
 764         size = strlen(newval) + 1;
 765         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 766                 size += 2;
 767                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 768                 *val++ = '0';
 769                 *val++ = 'x';
 770         } else if (!oldval || strcmp(oldval, newval))
 771                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 772         else
 773                 return true;
 774
 775         strcpy(val, newval);
 776         free((void *)oldval);
 777         sym_clear_all_valid();
 778
 779         return true;
 780 }
 781
 782 /*
 783  * Find the default value associated to a symbol.
 784  * For tristate symbol handle the modules=n case
 785  * in which case "m" becomes "y".
 786  * If the symbol does not have any default then fallback
 787  * to the fixed default values.
 788  */
 789 const char *sym_get_string_default(struct symbol *sym)
 790 {
 791         struct property *prop;
 792         struct symbol *ds;
 793         const char *str = "";
 794         tristate val;
 795
 796         sym_calc_visibility(sym);
 797         sym_calc_value(modules_sym);
 798         val = symbol_no.curr.tri;
 799
 800         /* If symbol has a default value look it up */
 801         prop = sym_get_default_prop(sym);
 802         if (prop != NULL) {
 803                 switch (sym->type) {
 804                 case S_BOOLEAN:
 805                 case S_TRISTATE:
 806                         /* The visibility may limit the value from yes => mod */
 807                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 808                         break;
 809                 default:
 810                         /*
 811                          * The following fails to handle the situation
 812                          * where a default value is further limited by
 813                          * the valid range.
 814                          */
 815                         ds = prop_get_symbol(prop);
 816                         if (ds != NULL) {
 817                                 sym_calc_value(ds);
 818                                 str = (const char *)ds->curr.val;
 819                         }
 820                 }
 821         }
 822
 823         /* Handle select statements */
 824         val = EXPR_OR(val, sym->rev_dep.tri);
 825
 826         /* transpose mod to yes if modules are not enabled */
 827         if (val == mod)
 828                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 829                         val = yes;
 830
 831         /* transpose mod to yes if type is bool */
 832         if (sym->type == S_BOOLEAN && val == mod)
 833                 val = yes;
 834
 835         /* adjust the default value if this symbol is implied by another */
 836         if (val < sym->implied.tri)
 837                 val = sym->implied.tri;
 838
 839         switch (sym->type) {
 840         case S_BOOLEAN:
 841         case S_TRISTATE:
 842                 switch (val) {
 843                 case no: return "n";
 844                 case mod: return "m";
 845                 case yes: return "y";
 846                 }
 847         case S_INT:
 848                 if (!str[0])
 849                         str = "0";
 850                 break;
 851         case S_HEX:
 852                 if (!str[0])
 853                         str = "0x0";
 854                 break;
 855         default:
 856                 break;
 857         }
 858         return str;
 859 }
 860
 861 const char *sym_get_string_value(struct symbol *sym)
 862 {
 863         tristate val;
 864
 865         switch (sym->type) {
 866         case S_BOOLEAN:
 867         case S_TRISTATE:
 868                 val = sym_get_tristate_value(sym);
 869                 switch (val) {
 870                 case no:
 871                         return "n";
 872                 case mod:
 873                         return "m";
 874                 case yes:
 875                         return "y";
 876                 }
 877                 break;
 878         default:
 879                 ;
 880         }
 881         return (const char *)sym->curr.val;
 882 }
 883
 884 bool sym_is_changeable(const struct symbol *sym)
 885 {
 886         return !sym_is_choice(sym) && sym->visible > sym->rev_dep.tri;
 887 }
 888
 889 bool sym_is_choice_value(const struct symbol *sym)
 890 {
 891         return !list_empty(&sym->choice_link);
 892 }
 893
 894 HASHTABLE_DEFINE(sym_hashtable, SYMBOL_HASHSIZE);
 895
 896 struct symbol *sym_lookup(const char *name, int flags)
 897 {
 898         struct symbol *symbol;
 899         char *new_name;
 900         int hash;
 901
 902         if (name) {
 903                 if (name[0] && !name[1]) {
 904                         switch (name[0]) {
 905                         case 'y': return &symbol_yes;
 906                         case 'm': return &symbol_mod;
 907                         case 'n': return &symbol_no;
 908                         }
 909                 }
 910                 hash = hash_str(name);
 911
 912                 hash_for_each_possible(sym_hashtable, symbol, node, hash) {
 913                         if (symbol->name &&
 914                             !strcmp(symbol->name, name) &&
 915                             (flags ? symbol->flags & flags
 916                                    : !(symbol->flags & SYMBOL_CONST)))
 917                                 return symbol;
 918                 }
 919                 new_name = xstrdup(name);
 920         } else {
 921                 new_name = NULL;
 922                 hash = 0;
 923         }
 924
 925         symbol = xmalloc(sizeof(*symbol));
 926         memset(symbol, 0, sizeof(*symbol));
 927         symbol->name = new_name;
 928         symbol->type = S_UNKNOWN;
 929         symbol->flags = flags;
 930         INIT_LIST_HEAD(&symbol->menus);
 931         INIT_LIST_HEAD(&symbol->choice_link);
 932
 933         hash_add(sym_hashtable, &symbol->node, hash);
 934
 935         return symbol;
 936 }
 937
 938 struct symbol *sym_find(const char *name)
 939 {
 940         struct symbol *symbol = NULL;
 941         int hash = 0;
 942
 943         if (!name)
 944                 return NULL;
 945
 946         if (name[0] && !name[1]) {
 947                 switch (name[0]) {
 948                 case 'y': return &symbol_yes;
 949                 case 'm': return &symbol_mod;
 950                 case 'n': return &symbol_no;
 951                 }
 952         }
 953         hash = hash_str(name);
 954
 955         hash_for_each_possible(sym_hashtable, symbol, node, hash) {
 956                 if (symbol->name &&
 957                     !strcmp(symbol->name, name) &&
 958                     !(symbol->flags & SYMBOL_CONST))
 959                                 break;
 960         }
 961
 962         return symbol;
 963 }
 964
 965 struct sym_match {
 966         struct symbol   *sym;
 967         off_t           so, eo;
 968 };
 969
 970 /* Compare matched symbols as thus:
 971  * - first, symbols that match exactly
 972  * - then, alphabetical sort
 973  */
 974 static int sym_rel_comp(const void *sym1, const void *sym2)
 975 {
 976         const struct sym_match *s1 = sym1;
 977         const struct sym_match *s2 = sym2;
 978         int exact1, exact2;
 979
 980         /* Exact match:
 981          * - if matched length on symbol s1 is the length of that symbol,
 982          *   then this symbol should come first;
 983          * - if matched length on symbol s2 is the length of that symbol,
 984          *   then this symbol should come first.
 985          * Note: since the search can be a regexp, both symbols may match
 986          * exactly; if this is the case, we can't decide which comes first,
 987          * and we fallback to sorting alphabetically.
 988          */
 989         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 990         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 991         if (exact1 && !exact2)
 992                 return -1;
 993         if (!exact1 && exact2)
 994                 return 1;
 995
 996         /* As a fallback, sort symbols alphabetically */
 997         return strcmp(s1->sym->name, s2->sym->name);
 998 }
 999
1000 struct symbol **sym_re_search(const char *pattern)
1001 {
1002         struct symbol *sym, **sym_arr = NULL;
1003         struct sym_match *sym_match_arr = NULL;
1004         int i, cnt, size;
1005         regex_t re;
1006         regmatch_t match[1];
1007
1008         cnt = size = 0;
1009         /* Skip if empty */
1010         if (strlen(pattern) == 0)
1011                 return NULL;
1012         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
1013                 return NULL;
1014
1015         for_all_symbols(sym) {
1016                 if (sym->flags & SYMBOL_CONST || !sym->name)
1017                         continue;
1018                 if (regexec(&re, sym->name, 1, match, 0))
1019                         continue;
1020                 if (cnt >= size) {
1021                         void *tmp;
1022                         size += 16;
1023                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
1024                         if (!tmp)
1025                                 goto sym_re_search_free;
1026                         sym_match_arr = tmp;
1027                 }
1028                 sym_calc_value(sym);
1029                 /* As regexec returned 0, we know we have a match, so
1030                  * we can use match[0].rm_[se]o without further checks
1031                  */
1032                 sym_match_arr[cnt].so = match[0].rm_so;
1033                 sym_match_arr[cnt].eo = match[0].rm_eo;
1034                 sym_match_arr[cnt++].sym = sym;
1035         }
1036         if (sym_match_arr) {
1037                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
1038                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
1039                 if (!sym_arr)
1040                         goto sym_re_search_free;
1041                 for (i = 0; i < cnt; i++)
1042                         sym_arr[i] = sym_match_arr[i].sym;
1043                 sym_arr[cnt] = NULL;
1044         }
1045 sym_re_search_free:
1046         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1047         free(sym_match_arr);
1048         regfree(&re);
1049
1050         return sym_arr;
1051 }
1052
1053 /*
1054  * When we check for recursive dependencies we use a stack to save
1055  * current state so we can print out relevant info to user.
1056  * The entries are located on the call stack so no need to free memory.
1057  * Note insert() remove() must always match to properly clear the stack.
1058  */
1059 static struct dep_stack {
1060         struct dep_stack *prev, *next;
1061         struct symbol *sym;
1062         struct property *prop;
1063         struct expr **expr;
1064 } *check_top;
1065
1066 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1067 {
1068         memset(stack, 0, sizeof(*stack));
1069         if (check_top)
1070                 check_top->next = stack;
1071         stack->prev = check_top;
1072         stack->sym = sym;
1073         check_top = stack;
1074 }
1075
1076 static void dep_stack_remove(void)
1077 {
1078         check_top = check_top->prev;
1079         if (check_top)
1080                 check_top->next = NULL;
1081 }
1082
1083 /*
1084  * Called when we have detected a recursive dependency.
1085  * check_top point to the top of the stact so we use
1086  * the ->prev pointer to locate the bottom of the stack.
1087  */
1088 static void sym_check_print_recursive(struct symbol *last_sym)
1089 {
1090         struct dep_stack *stack;
1091         struct symbol *sym, *next_sym;
1092         struct menu *choice;
1093         struct dep_stack cv_stack;
1094         enum prop_type type;
1095
1096         choice = sym_get_choice_menu(last_sym);
1097         if (choice) {
1098                 dep_stack_insert(&cv_stack, last_sym);
1099                 last_sym = choice->sym;
1100         }
1101
1102         for (stack = check_top; stack != NULL; stack = stack->prev)
1103                 if (stack->sym == last_sym)
1104                         break;
1105         if (!stack) {
1106                 fprintf(stderr, "unexpected recursive dependency error\n");
1107                 return;
1108         }
1109
1110         for (; stack; stack = stack->next) {
1111                 sym = stack->sym;
1112                 next_sym = stack->next ? stack->next->sym : last_sym;
1113                 type = stack->prop ? stack->prop->type : P_UNKNOWN;
1114
1115                 if (stack->sym == last_sym)
1116                         fprintf(stderr, "error: recursive dependency detected!\n");
1117
1118                 if (sym_is_choice(next_sym)) {
1119                         choice = list_first_entry(&next_sym->menus, struct menu, link);
1120
1121                         fprintf(stderr, "\tsymbol %s is part of choice block at %s:%d\n",
1122                                 sym->name ? sym->name : "<choice>",
1123                                 choice->filename, choice->lineno);
1124                 } else if (stack->expr == &sym->dir_dep.expr) {
1125                         fprintf(stderr, "\tsymbol %s depends on %s\n",
1126                                 sym->name ? sym->name : "<choice>",
1127                                 next_sym->name);
1128                 } else if (stack->expr == &sym->rev_dep.expr) {
1129                         fprintf(stderr, "\tsymbol %s is selected by %s\n",
1130                                 sym->name, next_sym->name);
1131                 } else if (stack->expr == &sym->implied.expr) {
1132                         fprintf(stderr, "\tsymbol %s is implied by %s\n",
1133                                 sym->name, next_sym->name);
1134                 } else if (stack->expr) {
1135                         fprintf(stderr, "\tsymbol %s %s value contains %s\n",
1136                                 sym->name ? sym->name : "<choice>",
1137                                 prop_get_type_name(type),
1138                                 next_sym->name);
1139                 } else {
1140                         fprintf(stderr, "\tsymbol %s %s is visible depending on %s\n",
1141                                 sym->name ? sym->name : "<choice>",
1142                                 prop_get_type_name(type),
1143                                 next_sym->name);
1144                 }
1145         }
1146
1147         fprintf(stderr,
1148                 "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1149                 "subsection \"Kconfig recursive dependency limitations\"\n"
1150                 "\n");
1151
1152         if (check_top == &cv_stack)
1153                 dep_stack_remove();
1154 }
1155
1156 static struct symbol *sym_check_expr_deps(const struct expr *e)
1157 {
1158         struct symbol *sym;
1159
1160         if (!e)
1161                 return NULL;
1162         switch (e->type) {
1163         case E_OR:
1164         case E_AND:
1165                 sym = sym_check_expr_deps(e->left.expr);
1166                 if (sym)
1167                         return sym;
1168                 return sym_check_expr_deps(e->right.expr);
1169         case E_NOT:
1170                 return sym_check_expr_deps(e->left.expr);
1171         case E_EQUAL:
1172         case E_GEQ:
1173         case E_GTH:
1174         case E_LEQ:
1175         case E_LTH:
1176         case E_UNEQUAL:
1177                 sym = sym_check_deps(e->left.sym);
1178                 if (sym)
1179                         return sym;
1180                 return sym_check_deps(e->right.sym);
1181         case E_SYMBOL:
1182                 return sym_check_deps(e->left.sym);
1183         default:
1184                 break;
1185         }
1186         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1187         return NULL;
1188 }
1189
1190 /* return NULL when dependencies are OK */
1191 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1192 {
1193         struct symbol *sym2;
1194         struct property *prop;
1195         struct dep_stack stack;
1196
1197         dep_stack_insert(&stack, sym);
1198
1199         stack.expr = &sym->dir_dep.expr;
1200         sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1201         if (sym2)
1202                 goto out;
1203
1204         stack.expr = &sym->rev_dep.expr;
1205         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1206         if (sym2)
1207                 goto out;
1208
1209         stack.expr = &sym->implied.expr;
1210         sym2 = sym_check_expr_deps(sym->implied.expr);
1211         if (sym2)
1212                 goto out;
1213
1214         stack.expr = NULL;
1215
1216         for (prop = sym->prop; prop; prop = prop->next) {
1217                 if (prop->type == P_SELECT || prop->type == P_IMPLY)
1218                         continue;
1219                 stack.prop = prop;
1220                 sym2 = sym_check_expr_deps(prop->visible.expr);
1221                 if (sym2)
1222                         break;
1223                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1224                         continue;
1225                 stack.expr = &prop->expr;
1226                 sym2 = sym_check_expr_deps(prop->expr);
1227                 if (sym2)
1228                         break;
1229                 stack.expr = NULL;
1230         }
1231
1232 out:
1233         dep_stack_remove();
1234
1235         return sym2;
1236 }
1237
1238 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1239 {
1240         struct menu *choice_menu, *menu;
1241         struct symbol *sym2;
1242         struct dep_stack stack;
1243
1244         dep_stack_insert(&stack, choice);
1245
1246         choice_menu = list_first_entry(&choice->menus, struct menu, link);
1247
1248         menu_for_each_sub_entry(menu, choice_menu) {
1249                 if (menu->sym)
1250                         menu->sym->flags |= SYMBOL_CHECK | SYMBOL_CHECKED;
1251         }
1252
1253         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1254         sym2 = sym_check_sym_deps(choice);
1255         choice->flags &= ~SYMBOL_CHECK;
1256         if (sym2)
1257                 goto out;
1258
1259         menu_for_each_sub_entry(menu, choice_menu) {
1260                 if (!menu->sym)
1261                         continue;
1262                 sym2 = sym_check_sym_deps(menu->sym);
1263                 if (sym2)
1264                         break;
1265         }
1266 out:
1267         menu_for_each_sub_entry(menu, choice_menu)
1268                 if (menu->sym)
1269                         menu->sym->flags &= ~SYMBOL_CHECK;
1270
1271         if (sym2) {
1272                 struct menu *choice_menu2;
1273
1274                 choice_menu2 = sym_get_choice_menu(sym2);
1275                 if (choice_menu2 == choice_menu)
1276                         sym2 = choice;
1277         }
1278
1279         dep_stack_remove();
1280
1281         return sym2;
1282 }
1283
1284 struct symbol *sym_check_deps(struct symbol *sym)
1285 {
1286         struct menu *choice;
1287         struct symbol *sym2;
1288
1289         if (sym->flags & SYMBOL_CHECK) {
1290                 sym_check_print_recursive(sym);
1291                 return sym;
1292         }
1293         if (sym->flags & SYMBOL_CHECKED)
1294                 return NULL;
1295
1296         choice = sym_get_choice_menu(sym);
1297         if (choice) {
1298                 struct dep_stack stack;
1299
1300                 /* for choice groups start the check with main choice symbol */
1301                 dep_stack_insert(&stack, sym);
1302                 sym2 = sym_check_deps(choice->sym);
1303                 dep_stack_remove();
1304         } else if (sym_is_choice(sym)) {
1305                 sym2 = sym_check_choice_deps(sym);
1306         } else {
1307                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1308                 sym2 = sym_check_sym_deps(sym);
1309                 sym->flags &= ~SYMBOL_CHECK;
1310         }
1311
1312         return sym2;
1313 }
1314
1315 struct symbol *prop_get_symbol(const struct property *prop)
1316 {
1317         if (prop->expr && prop->expr->type == E_SYMBOL)
1318                 return prop->expr->left.sym;
1319         return NULL;
1320 }
1321
1322 const char *prop_get_type_name(enum prop_type type)
1323 {
1324         switch (type) {
1325         case P_PROMPT:
1326                 return "prompt";
1327         case P_COMMENT:
1328                 return "comment";
1329         case P_MENU:
1330                 return "menu";
1331         case P_DEFAULT:
1332                 return "default";
1333         case P_SELECT:
1334                 return "select";
1335         case P_IMPLY:
1336                 return "imply";
1337         case P_RANGE:
1338                 return "range";
1339         case P_UNKNOWN:
1340                 break;
1341         }
1342         return "unknown";
1343 }