linux/scripts/kconfig/symbol.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   4 */
   5
   6#include <sys/types.h>
   7#include <ctype.h>
   8#include <stdlib.h>
   9#include <string.h>
  10#include <regex.h>
  11
  12#include "lkc.h"
  13
  14struct symbol symbol_yes = {
  15        .name = "y",
  16        .curr = { "y", yes },
  17        .flags = SYMBOL_CONST|SYMBOL_VALID,
  18};
  19
  20struct symbol symbol_mod = {
  21        .name = "m",
  22        .curr = { "m", mod },
  23        .flags = SYMBOL_CONST|SYMBOL_VALID,
  24};
  25
  26struct symbol symbol_no = {
  27        .name = "n",
  28        .curr = { "n", no },
  29        .flags = SYMBOL_CONST|SYMBOL_VALID,
  30};
  31
  32static struct symbol symbol_empty = {
  33        .name = "",
  34        .curr = { "", no },
  35        .flags = SYMBOL_VALID,
  36};
  37
  38struct symbol *modules_sym;
  39static tristate modules_val;
  40
  41enum symbol_type sym_get_type(struct symbol *sym)
  42{
  43        enum symbol_type type = sym->type;
  44
  45        if (type == S_TRISTATE) {
  46                if (sym_is_choice_value(sym) && sym->visible == yes)
  47                        type = S_BOOLEAN;
  48                else if (modules_val == no)
  49                        type = S_BOOLEAN;
  50        }
  51        return type;
  52}
  53
  54const 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
  73struct property *sym_get_choice_prop(struct symbol *sym)
  74{
  75        struct property *prop;
  76
  77        for_all_choices(sym, prop)
  78                return prop;
  79        return NULL;
  80}
  81
  82static struct property *sym_get_default_prop(struct symbol *sym)
  83{
  84        struct property *prop;
  85
  86        for_all_defaults(sym, prop) {
  87                prop->visible.tri = expr_calc_value(prop->visible.expr);
  88                if (prop->visible.tri != no)
  89                        return prop;
  90        }
  91        return NULL;
  92}
  93
  94struct property *sym_get_range_prop(struct symbol *sym)
  95{
  96        struct property *prop;
  97
  98        for_all_properties(sym, prop, P_RANGE) {
  99                prop->visible.tri = expr_calc_value(prop->visible.expr);
 100                if (prop->visible.tri != no)
 101                        return prop;
 102        }
 103        return NULL;
 104}
 105
 106static long long sym_get_range_val(struct symbol *sym, int base)
 107{
 108        sym_calc_value(sym);
 109        switch (sym->type) {
 110        case S_INT:
 111                base = 10;
 112                break;
 113        case S_HEX:
 114                base = 16;
 115                break;
 116        default:
 117                break;
 118        }
 119        return strtoll(sym->curr.val, NULL, base);
 120}
 121
 122static void sym_validate_range(struct symbol *sym)
 123{
 124        struct property *prop;
 125        int base;
 126        long long val, val2;
 127        char str[64];
 128
 129        switch (sym->type) {
 130        case S_INT:
 131                base = 10;
 132                break;
 133        case S_HEX:
 134                base = 16;
 135                break;
 136        default:
 137                return;
 138        }
 139        prop = sym_get_range_prop(sym);
 140        if (!prop)
 141                return;
 142        val = strtoll(sym->curr.val, NULL, base);
 143        val2 = sym_get_range_val(prop->expr->left.sym, base);
 144        if (val >= val2) {
 145                val2 = sym_get_range_val(prop->expr->right.sym, base);
 146                if (val <= val2)
 147                        return;
 148        }
 149        if (sym->type == S_INT)
 150                sprintf(str, "%lld", val2);
 151        else
 152                sprintf(str, "0x%llx", val2);
 153        sym->curr.val = xstrdup(str);
 154}
 155
 156static void sym_set_changed(struct symbol *sym)
 157{
 158        struct property *prop;
 159
 160        sym->flags |= SYMBOL_CHANGED;
 161        for (prop = sym->prop; prop; prop = prop->next) {
 162                if (prop->menu)
 163                        prop->menu->flags |= MENU_CHANGED;
 164        }
 165}
 166
 167static void sym_set_all_changed(void)
 168{
 169        struct symbol *sym;
 170        int i;
 171
 172        for_all_symbols(i, sym)
 173                sym_set_changed(sym);
 174}
 175
 176static void sym_calc_visibility(struct symbol *sym)
 177{
 178        struct property *prop;
 179        struct symbol *choice_sym = NULL;
 180        tristate tri;
 181
 182        /* any prompt visible? */
 183        tri = no;
 184
 185        if (sym_is_choice_value(sym))
 186                choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 187
 188        for_all_prompts(sym, prop) {
 189                prop->visible.tri = expr_calc_value(prop->visible.expr);
 190                /*
 191                 * Tristate choice_values with visibility 'mod' are
 192                 * not visible if the corresponding choice's value is
 193                 * 'yes'.
 194                 */
 195                if (choice_sym && sym->type == S_TRISTATE &&
 196                    prop->visible.tri == mod && choice_sym->curr.tri == yes)
 197                        prop->visible.tri = no;
 198
 199                tri = EXPR_OR(tri, prop->visible.tri);
 200        }
 201        if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 202                tri = yes;
 203        if (sym->visible != tri) {
 204                sym->visible = tri;
 205                sym_set_changed(sym);
 206        }
 207        if (sym_is_choice_value(sym))
 208                return;
 209        /* defaulting to "yes" if no explicit "depends on" are given */
 210        tri = yes;
 211        if (sym->dir_dep.expr)
 212                tri = expr_calc_value(sym->dir_dep.expr);
 213        if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 214                tri = yes;
 215        if (sym->dir_dep.tri != tri) {
 216                sym->dir_dep.tri = tri;
 217                sym_set_changed(sym);
 218        }
 219        tri = no;
 220        if (sym->rev_dep.expr)
 221                tri = expr_calc_value(sym->rev_dep.expr);
 222        if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 223                tri = yes;
 224        if (sym->rev_dep.tri != tri) {
 225                sym->rev_dep.tri = tri;
 226                sym_set_changed(sym);
 227        }
 228        tri = no;
 229        if (sym->implied.expr)
 230                tri = expr_calc_value(sym->implied.expr);
 231        if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 232                tri = yes;
 233        if (sym->implied.tri != tri) {
 234                sym->implied.tri = tri;
 235                sym_set_changed(sym);
 236        }
 237}
 238
 239/*
 240 * Find the default symbol for a choice.
 241 * First try the default values for the choice symbol
 242 * Next locate the first visible choice value
 243 * Return NULL if none was found
 244 */
 245struct symbol *sym_choice_default(struct symbol *sym)
 246{
 247        struct symbol *def_sym;
 248        struct property *prop;
 249        struct expr *e;
 250
 251        /* any of the defaults visible? */
 252        for_all_defaults(sym, prop) {
 253                prop->visible.tri = expr_calc_value(prop->visible.expr);
 254                if (prop->visible.tri == no)
 255                        continue;
 256                def_sym = prop_get_symbol(prop);
 257                if (def_sym->visible != no)
 258                        return def_sym;
 259        }
 260
 261        /* just get the first visible value */
 262        prop = sym_get_choice_prop(sym);
 263        expr_list_for_each_sym(prop->expr, e, def_sym)
 264                if (def_sym->visible != no)
 265                        return def_sym;
 266
 267        /* failed to locate any defaults */
 268        return NULL;
 269}
 270
 271static struct symbol *sym_calc_choice(struct symbol *sym)
 272{
 273        struct symbol *def_sym;
 274        struct property *prop;
 275        struct expr *e;
 276        int flags;
 277
 278        /* first calculate all choice values' visibilities */
 279        flags = sym->flags;
 280        prop = sym_get_choice_prop(sym);
 281        expr_list_for_each_sym(prop->expr, e, def_sym) {
 282                sym_calc_visibility(def_sym);
 283                if (def_sym->visible != no)
 284                        flags &= def_sym->flags;
 285        }
 286
 287        sym->flags &= flags | ~SYMBOL_DEF_USER;
 288
 289        /* is the user choice visible? */
 290        def_sym = sym->def[S_DEF_USER].val;
 291        if (def_sym && def_sym->visible != no)
 292                return def_sym;
 293
 294        def_sym = sym_choice_default(sym);
 295
 296        if (def_sym == NULL)
 297                /* no choice? reset tristate value */
 298                sym->curr.tri = no;
 299
 300        return def_sym;
 301}
 302
 303static void sym_warn_unmet_dep(struct symbol *sym)
 304{
 305        struct gstr gs = str_new();
 306
 307        str_printf(&gs,
 308                   "\nWARNING: unmet direct dependencies detected for %s\n",
 309                   sym->name);
 310        str_printf(&gs,
 311                   "  Depends on [%c]: ",
 312                   sym->dir_dep.tri == mod ? 'm' : 'n');
 313        expr_gstr_print(sym->dir_dep.expr, &gs);
 314        str_printf(&gs, "\n");
 315
 316        expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 317                               "  Selected by [y]:\n");
 318        expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 319                               "  Selected by [m]:\n");
 320
 321        fputs(str_get(&gs), stderr);
 322}
 323
 324void sym_calc_value(struct symbol *sym)
 325{
 326        struct symbol_value newval, oldval;
 327        struct property *prop;
 328        struct expr *e;
 329
 330        if (!sym)
 331                return;
 332
 333        if (sym->flags & SYMBOL_VALID)
 334                return;
 335
 336        if (sym_is_choice_value(sym) &&
 337            sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 338                sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 339                prop = sym_get_choice_prop(sym);
 340                sym_calc_value(prop_get_symbol(prop));
 341        }
 342
 343        sym->flags |= SYMBOL_VALID;
 344
 345        oldval = sym->curr;
 346
 347        switch (sym->type) {
 348        case S_INT:
 349        case S_HEX:
 350        case S_STRING:
 351                newval = symbol_empty.curr;
 352                break;
 353        case S_BOOLEAN:
 354        case S_TRISTATE:
 355                newval = symbol_no.curr;
 356                break;
 357        default:
 358                sym->curr.val = sym->name;
 359                sym->curr.tri = no;
 360                return;
 361        }
 362        sym->flags &= ~SYMBOL_WRITE;
 363
 364        sym_calc_visibility(sym);
 365
 366        if (sym->visible != no)
 367                sym->flags |= SYMBOL_WRITE;
 368
 369        /* set default if recursively called */
 370        sym->curr = newval;
 371
 372        switch (sym_get_type(sym)) {
 373        case S_BOOLEAN:
 374        case S_TRISTATE:
 375                if (sym_is_choice_value(sym) && sym->visible == yes) {
 376                        prop = sym_get_choice_prop(sym);
 377                        newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 378                } else {
 379                        if (sym->visible != no) {
 380                                /* if the symbol is visible use the user value
 381                                 * if available, otherwise try the default value
 382                                 */
 383                                if (sym_has_value(sym)) {
 384                                        newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 385                                                              sym->visible);
 386                                        goto calc_newval;
 387                                }
 388                        }
 389                        if (sym->rev_dep.tri != no)
 390                                sym->flags |= SYMBOL_WRITE;
 391                        if (!sym_is_choice(sym)) {
 392                                prop = sym_get_default_prop(sym);
 393                                if (prop) {
 394                                        newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 395                                                              prop->visible.tri);
 396                                        if (newval.tri != no)
 397                                                sym->flags |= SYMBOL_WRITE;
 398                                }
 399                                if (sym->implied.tri != no) {
 400                                        sym->flags |= SYMBOL_WRITE;
 401                                        newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 402                                        newval.tri = EXPR_AND(newval.tri,
 403                                                              sym->dir_dep.tri);
 404                                }
 405                        }
 406                calc_newval:
 407                        if (sym->dir_dep.tri < sym->rev_dep.tri)
 408                                sym_warn_unmet_dep(sym);
 409                        newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 410                }
 411                if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 412                        newval.tri = yes;
 413                break;
 414        case S_STRING:
 415        case S_HEX:
 416        case S_INT:
 417                if (sym->visible != no && sym_has_value(sym)) {
 418                        newval.val = sym->def[S_DEF_USER].val;
 419                        break;
 420                }
 421                prop = sym_get_default_prop(sym);
 422                if (prop) {
 423                        struct symbol *ds = prop_get_symbol(prop);
 424                        if (ds) {
 425                                sym->flags |= SYMBOL_WRITE;
 426                                sym_calc_value(ds);
 427                                newval.val = ds->curr.val;
 428                        }
 429                }
 430                break;
 431        default:
 432                ;
 433        }
 434
 435        sym->curr = newval;
 436        if (sym_is_choice(sym) && newval.tri == yes)
 437                sym->curr.val = sym_calc_choice(sym);
 438        sym_validate_range(sym);
 439
 440        if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 441                sym_set_changed(sym);
 442                if (modules_sym == sym) {
 443                        sym_set_all_changed();
 444                        modules_val = modules_sym->curr.tri;
 445                }
 446        }
 447
 448        if (sym_is_choice(sym)) {
 449                struct symbol *choice_sym;
 450
 451                prop = sym_get_choice_prop(sym);
 452                expr_list_for_each_sym(prop->expr, e, choice_sym) {
 453                        if ((sym->flags & SYMBOL_WRITE) &&
 454                            choice_sym->visible != no)
 455                                choice_sym->flags |= SYMBOL_WRITE;
 456                        if (sym->flags & SYMBOL_CHANGED)
 457                                sym_set_changed(choice_sym);
 458                }
 459        }
 460
 461        if (sym->flags & SYMBOL_NO_WRITE)
 462                sym->flags &= ~SYMBOL_WRITE;
 463
 464        if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 465                set_all_choice_values(sym);
 466}
 467
 468void sym_clear_all_valid(void)
 469{
 470        struct symbol *sym;
 471        int i;
 472
 473        for_all_symbols(i, sym)
 474                sym->flags &= ~SYMBOL_VALID;
 475        conf_set_changed(true);
 476        sym_calc_value(modules_sym);
 477}
 478
 479bool sym_tristate_within_range(struct symbol *sym, tristate val)
 480{
 481        int type = sym_get_type(sym);
 482
 483        if (sym->visible == no)
 484                return false;
 485
 486        if (type != S_BOOLEAN && type != S_TRISTATE)
 487                return false;
 488
 489        if (type == S_BOOLEAN && val == mod)
 490                return false;
 491        if (sym->visible <= sym->rev_dep.tri)
 492                return false;
 493        if (sym_is_choice_value(sym) && sym->visible == yes)
 494                return val == yes;
 495        return val >= sym->rev_dep.tri && val <= sym->visible;
 496}
 497
 498bool sym_set_tristate_value(struct symbol *sym, tristate val)
 499{
 500        tristate oldval = sym_get_tristate_value(sym);
 501
 502        if (oldval != val && !sym_tristate_within_range(sym, val))
 503                return false;
 504
 505        if (!(sym->flags & SYMBOL_DEF_USER)) {
 506                sym->flags |= SYMBOL_DEF_USER;
 507                sym_set_changed(sym);
 508        }
 509        /*
 510         * setting a choice value also resets the new flag of the choice
 511         * symbol and all other choice values.
 512         */
 513        if (sym_is_choice_value(sym) && val == yes) {
 514                struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 515                struct property *prop;
 516                struct expr *e;
 517
 518                cs->def[S_DEF_USER].val = sym;
 519                cs->flags |= SYMBOL_DEF_USER;
 520                prop = sym_get_choice_prop(cs);
 521                for (e = prop->expr; e; e = e->left.expr) {
 522                        if (e->right.sym->visible != no)
 523                                e->right.sym->flags |= SYMBOL_DEF_USER;
 524                }
 525        }
 526
 527        sym->def[S_DEF_USER].tri = val;
 528        if (oldval != val)
 529                sym_clear_all_valid();
 530
 531        return true;
 532}
 533
 534tristate sym_toggle_tristate_value(struct symbol *sym)
 535{
 536        tristate oldval, newval;
 537
 538        oldval = newval = sym_get_tristate_value(sym);
 539        do {
 540                switch (newval) {
 541                case no:
 542                        newval = mod;
 543                        break;
 544                case mod:
 545                        newval = yes;
 546                        break;
 547                case yes:
 548                        newval = no;
 549                        break;
 550                }
 551                if (sym_set_tristate_value(sym, newval))
 552                        break;
 553        } while (oldval != newval);
 554        return newval;
 555}
 556
 557bool sym_string_valid(struct symbol *sym, const char *str)
 558{
 559        signed char ch;
 560
 561        switch (sym->type) {
 562        case S_STRING:
 563                return true;
 564        case S_INT:
 565                ch = *str++;
 566                if (ch == '-')
 567                        ch = *str++;
 568                if (!isdigit(ch))
 569                        return false;
 570                if (ch == '0' && *str != 0)
 571                        return false;
 572                while ((ch = *str++)) {
 573                        if (!isdigit(ch))
 574                                return false;
 575                }
 576                return true;
 577        case S_HEX:
 578                if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 579                        str += 2;
 580                ch = *str++;
 581                do {
 582                        if (!isxdigit(ch))
 583                                return false;
 584                } while ((ch = *str++));
 585                return true;
 586        case S_BOOLEAN:
 587        case S_TRISTATE:
 588                switch (str[0]) {
 589                case 'y': case 'Y':
 590                case 'm': case 'M':
 591                case 'n': case 'N':
 592                        return true;
 593                }
 594                return false;
 595        default:
 596                return false;
 597        }
 598}
 599
 600bool sym_string_within_range(struct symbol *sym, const char *str)
 601{
 602        struct property *prop;
 603        long long val;
 604
 605        switch (sym->type) {
 606        case S_STRING:
 607                return sym_string_valid(sym, str);
 608        case S_INT:
 609                if (!sym_string_valid(sym, str))
 610                        return false;
 611                prop = sym_get_range_prop(sym);
 612                if (!prop)
 613                        return true;
 614                val = strtoll(str, NULL, 10);
 615                return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 616                       val <= sym_get_range_val(prop->expr->right.sym, 10);
 617        case S_HEX:
 618                if (!sym_string_valid(sym, str))
 619                        return false;
 620                prop = sym_get_range_prop(sym);
 621                if (!prop)
 622                        return true;
 623                val = strtoll(str, NULL, 16);
 624                return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 625                       val <= sym_get_range_val(prop->expr->right.sym, 16);
 626        case S_BOOLEAN:
 627        case S_TRISTATE:
 628                switch (str[0]) {
 629                case 'y': case 'Y':
 630                        return sym_tristate_within_range(sym, yes);
 631                case 'm': case 'M':
 632                        return sym_tristate_within_range(sym, mod);
 633                case 'n': case 'N':
 634                        return sym_tristate_within_range(sym, no);
 635                }
 636                return false;
 637        default:
 638                return false;
 639        }
 640}
 641
 642bool sym_set_string_value(struct symbol *sym, const char *newval)
 643{
 644        const char *oldval;
 645        char *val;
 646        int size;
 647
 648        switch (sym->type) {
 649        case S_BOOLEAN:
 650        case S_TRISTATE:
 651                switch (newval[0]) {
 652                case 'y': case 'Y':
 653                        return sym_set_tristate_value(sym, yes);
 654                case 'm': case 'M':
 655                        return sym_set_tristate_value(sym, mod);
 656                case 'n': case 'N':
 657                        return sym_set_tristate_value(sym, no);
 658                }
 659                return false;
 660        default:
 661                ;
 662        }
 663
 664        if (!sym_string_within_range(sym, newval))
 665                return false;
 666
 667        if (!(sym->flags & SYMBOL_DEF_USER)) {
 668                sym->flags |= SYMBOL_DEF_USER;
 669                sym_set_changed(sym);
 670        }
 671
 672        oldval = sym->def[S_DEF_USER].val;
 673        size = strlen(newval) + 1;
 674        if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 675                size += 2;
 676                sym->def[S_DEF_USER].val = val = xmalloc(size);
 677                *val++ = '0';
 678                *val++ = 'x';
 679        } else if (!oldval || strcmp(oldval, newval))
 680                sym->def[S_DEF_USER].val = val = xmalloc(size);
 681        else
 682                return true;
 683
 684        strcpy(val, newval);
 685        free((void *)oldval);
 686        sym_clear_all_valid();
 687
 688        return true;
 689}
 690
 691/*
 692 * Find the default value associated to a symbol.
 693 * For tristate symbol handle the modules=n case
 694 * in which case "m" becomes "y".
 695 * If the symbol does not have any default then fallback
 696 * to the fixed default values.
 697 */
 698const char *sym_get_string_default(struct symbol *sym)
 699{
 700        struct property *prop;
 701        struct symbol *ds;
 702        const char *str;
 703        tristate val;
 704
 705        sym_calc_visibility(sym);
 706        sym_calc_value(modules_sym);
 707        val = symbol_no.curr.tri;
 708        str = symbol_empty.curr.val;
 709
 710        /* If symbol has a default value look it up */
 711        prop = sym_get_default_prop(sym);
 712        if (prop != NULL) {
 713                switch (sym->type) {
 714                case S_BOOLEAN:
 715                case S_TRISTATE:
 716                        /* The visibility may limit the value from yes => mod */
 717                        val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 718                        break;
 719                default:
 720                        /*
 721                         * The following fails to handle the situation
 722                         * where a default value is further limited by
 723                         * the valid range.
 724                         */
 725                        ds = prop_get_symbol(prop);
 726                        if (ds != NULL) {
 727                                sym_calc_value(ds);
 728                                str = (const char *)ds->curr.val;
 729                        }
 730                }
 731        }
 732
 733        /* Handle select statements */
 734        val = EXPR_OR(val, sym->rev_dep.tri);
 735
 736        /* transpose mod to yes if modules are not enabled */
 737        if (val == mod)
 738                if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 739                        val = yes;
 740
 741        /* transpose mod to yes if type is bool */
 742        if (sym->type == S_BOOLEAN && val == mod)
 743                val = yes;
 744
 745        /* adjust the default value if this symbol is implied by another */
 746        if (val < sym->implied.tri)
 747                val = sym->implied.tri;
 748
 749        switch (sym->type) {
 750        case S_BOOLEAN:
 751        case S_TRISTATE:
 752                switch (val) {
 753                case no: return "n";
 754                case mod: return "m";
 755                case yes: return "y";
 756                }
 757        case S_INT:
 758        case S_HEX:
 759                return str;
 760        case S_STRING:
 761                return str;
 762        case S_UNKNOWN:
 763                break;
 764        }
 765        return "";
 766}
 767
 768const char *sym_get_string_value(struct symbol *sym)
 769{
 770        tristate val;
 771
 772        switch (sym->type) {
 773        case S_BOOLEAN:
 774        case S_TRISTATE:
 775                val = sym_get_tristate_value(sym);
 776                switch (val) {
 777                case no:
 778                        return "n";
 779                case mod:
 780                        sym_calc_value(modules_sym);
 781                        return (modules_sym->curr.tri == no) ? "n" : "m";
 782                case yes:
 783                        return "y";
 784                }
 785                break;
 786        default:
 787                ;
 788        }
 789        return (const char *)sym->curr.val;
 790}
 791
 792bool sym_is_changeable(struct symbol *sym)
 793{
 794        return sym->visible > sym->rev_dep.tri;
 795}
 796
 797static unsigned strhash(const char *s)
 798{
 799        /* fnv32 hash */
 800        unsigned hash = 2166136261U;
 801        for (; *s; s++)
 802                hash = (hash ^ *s) * 0x01000193;
 803        return hash;
 804}
 805
 806struct symbol *sym_lookup(const char *name, int flags)
 807{
 808        struct symbol *symbol;
 809        char *new_name;
 810        int hash;
 811
 812        if (name) {
 813                if (name[0] && !name[1]) {
 814                        switch (name[0]) {
 815                        case 'y': return &symbol_yes;
 816                        case 'm': return &symbol_mod;
 817                        case 'n': return &symbol_no;
 818                        }
 819                }
 820                hash = strhash(name) % SYMBOL_HASHSIZE;
 821
 822                for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 823                        if (symbol->name &&
 824                            !strcmp(symbol->name, name) &&
 825                            (flags ? symbol->flags & flags
 826                                   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 827                                return symbol;
 828                }
 829                new_name = xstrdup(name);
 830        } else {
 831                new_name = NULL;
 832                hash = 0;
 833        }
 834
 835        symbol = xmalloc(sizeof(*symbol));
 836        memset(symbol, 0, sizeof(*symbol));
 837        symbol->name = new_name;
 838        symbol->type = S_UNKNOWN;
 839        symbol->flags = flags;
 840
 841        symbol->next = symbol_hash[hash];
 842        symbol_hash[hash] = symbol;
 843
 844        return symbol;
 845}
 846
 847struct symbol *sym_find(const char *name)
 848{
 849        struct symbol *symbol = NULL;
 850        int hash = 0;
 851
 852        if (!name)
 853                return NULL;
 854
 855        if (name[0] && !name[1]) {
 856                switch (name[0]) {
 857                case 'y': return &symbol_yes;
 858                case 'm': return &symbol_mod;
 859                case 'n': return &symbol_no;
 860                }
 861        }
 862        hash = strhash(name) % SYMBOL_HASHSIZE;
 863
 864        for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 865                if (symbol->name &&
 866                    !strcmp(symbol->name, name) &&
 867                    !(symbol->flags & SYMBOL_CONST))
 868                                break;
 869        }
 870
 871        return symbol;
 872}
 873
 874struct sym_match {
 875        struct symbol   *sym;
 876        off_t           so, eo;
 877};
 878
 879/* Compare matched symbols as thus:
 880 * - first, symbols that match exactly
 881 * - then, alphabetical sort
 882 */
 883static int sym_rel_comp(const void *sym1, const void *sym2)
 884{
 885        const struct sym_match *s1 = sym1;
 886        const struct sym_match *s2 = sym2;
 887        int exact1, exact2;
 888
 889        /* Exact match:
 890         * - if matched length on symbol s1 is the length of that symbol,
 891         *   then this symbol should come first;
 892         * - if matched length on symbol s2 is the length of that symbol,
 893         *   then this symbol should come first.
 894         * Note: since the search can be a regexp, both symbols may match
 895         * exactly; if this is the case, we can't decide which comes first,
 896         * and we fallback to sorting alphabetically.
 897         */
 898        exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 899        exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 900        if (exact1 && !exact2)
 901                return -1;
 902        if (!exact1 && exact2)
 903                return 1;
 904
 905        /* As a fallback, sort symbols alphabetically */
 906        return strcmp(s1->sym->name, s2->sym->name);
 907}
 908
 909struct symbol **sym_re_search(const char *pattern)
 910{
 911        struct symbol *sym, **sym_arr = NULL;
 912        struct sym_match *sym_match_arr = NULL;
 913        int i, cnt, size;
 914        regex_t re;
 915        regmatch_t match[1];
 916
 917        cnt = size = 0;
 918        /* Skip if empty */
 919        if (strlen(pattern) == 0)
 920                return NULL;
 921        if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 922                return NULL;
 923
 924        for_all_symbols(i, sym) {
 925                if (sym->flags & SYMBOL_CONST || !sym->name)
 926                        continue;
 927                if (regexec(&re, sym->name, 1, match, 0))
 928                        continue;
 929                if (cnt >= size) {
 930                        void *tmp;
 931                        size += 16;
 932                        tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 933                        if (!tmp)
 934                                goto sym_re_search_free;
 935                        sym_match_arr = tmp;
 936                }
 937                sym_calc_value(sym);
 938                /* As regexec returned 0, we know we have a match, so
 939                 * we can use match[0].rm_[se]o without further checks
 940                 */
 941                sym_match_arr[cnt].so = match[0].rm_so;
 942                sym_match_arr[cnt].eo = match[0].rm_eo;
 943                sym_match_arr[cnt++].sym = sym;
 944        }
 945        if (sym_match_arr) {
 946                qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 947                sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 948                if (!sym_arr)
 949                        goto sym_re_search_free;
 950                for (i = 0; i < cnt; i++)
 951                        sym_arr[i] = sym_match_arr[i].sym;
 952                sym_arr[cnt] = NULL;
 953        }
 954sym_re_search_free:
 955        /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
 956        free(sym_match_arr);
 957        regfree(&re);
 958
 959        return sym_arr;
 960}
 961
 962/*
 963 * When we check for recursive dependencies we use a stack to save
 964 * current state so we can print out relevant info to user.
 965 * The entries are located on the call stack so no need to free memory.
 966 * Note insert() remove() must always match to properly clear the stack.
 967 */
 968static struct dep_stack {
 969        struct dep_stack *prev, *next;
 970        struct symbol *sym;
 971        struct property *prop;
 972        struct expr **expr;
 973} *check_top;
 974
 975static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
 976{
 977        memset(stack, 0, sizeof(*stack));
 978        if (check_top)
 979                check_top->next = stack;
 980        stack->prev = check_top;
 981        stack->sym = sym;
 982        check_top = stack;
 983}
 984
 985static void dep_stack_remove(void)
 986{
 987        check_top = check_top->prev;
 988        if (check_top)
 989                check_top->next = NULL;
 990}
 991
 992/*
 993 * Called when we have detected a recursive dependency.
 994 * check_top point to the top of the stact so we use
 995 * the ->prev pointer to locate the bottom of the stack.
 996 */
 997static void sym_check_print_recursive(struct symbol *last_sym)
 998{
 999        struct dep_stack *stack;
1000        struct symbol *sym, *next_sym;
1001        struct menu *menu = NULL;
1002        struct property *prop;
1003        struct dep_stack cv_stack;
1004
1005        if (sym_is_choice_value(last_sym)) {
1006                dep_stack_insert(&cv_stack, last_sym);
1007                last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1008        }
1009
1010        for (stack = check_top; stack != NULL; stack = stack->prev)
1011                if (stack->sym == last_sym)
1012                        break;
1013        if (!stack) {
1014                fprintf(stderr, "unexpected recursive dependency error\n");
1015                return;
1016        }
1017
1018        for (; stack; stack = stack->next) {
1019                sym = stack->sym;
1020                next_sym = stack->next ? stack->next->sym : last_sym;
1021                prop = stack->prop;
1022                if (prop == NULL)
1023                        prop = stack->sym->prop;
1024
1025                /* for choice values find the menu entry (used below) */
1026                if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1027                        for (prop = sym->prop; prop; prop = prop->next) {
1028                                menu = prop->menu;
1029                                if (prop->menu)
1030                                        break;
1031                        }
1032                }
1033                if (stack->sym == last_sym)
1034                        fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1035                                prop->file->name, prop->lineno);
1036
1037                if (sym_is_choice(sym)) {
1038                        fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1039                                menu->file->name, menu->lineno,
1040                                sym->name ? sym->name : "<choice>",
1041                                next_sym->name ? next_sym->name : "<choice>");
1042                } else if (sym_is_choice_value(sym)) {
1043                        fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1044                                menu->file->name, menu->lineno,
1045                                sym->name ? sym->name : "<choice>",
1046                                next_sym->name ? next_sym->name : "<choice>");
1047                } else if (stack->expr == &sym->dir_dep.expr) {
1048                        fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1049                                prop->file->name, prop->lineno,
1050                                sym->name ? sym->name : "<choice>",
1051                                next_sym->name ? next_sym->name : "<choice>");
1052                } else if (stack->expr == &sym->rev_dep.expr) {
1053                        fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1054                                prop->file->name, prop->lineno,
1055                                sym->name ? sym->name : "<choice>",
1056                                next_sym->name ? next_sym->name : "<choice>");
1057                } else if (stack->expr == &sym->implied.expr) {
1058                        fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1059                                prop->file->name, prop->lineno,
1060                                sym->name ? sym->name : "<choice>",
1061                                next_sym->name ? next_sym->name : "<choice>");
1062                } else if (stack->expr) {
1063                        fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1064                                prop->file->name, prop->lineno,
1065                                sym->name ? sym->name : "<choice>",
1066                                prop_get_type_name(prop->type),
1067                                next_sym->name ? next_sym->name : "<choice>");
1068                } else {
1069                        fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1070                                prop->file->name, prop->lineno,
1071                                sym->name ? sym->name : "<choice>",
1072                                prop_get_type_name(prop->type),
1073                                next_sym->name ? next_sym->name : "<choice>");
1074                }
1075        }
1076
1077        fprintf(stderr,
1078                "For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1079                "subsection \"Kconfig recursive dependency limitations\"\n"
1080                "\n");
1081
1082        if (check_top == &cv_stack)
1083                dep_stack_remove();
1084}
1085
1086static struct symbol *sym_check_expr_deps(struct expr *e)
1087{
1088        struct symbol *sym;
1089
1090        if (!e)
1091                return NULL;
1092        switch (e->type) {
1093        case E_OR:
1094        case E_AND:
1095                sym = sym_check_expr_deps(e->left.expr);
1096                if (sym)
1097                        return sym;
1098                return sym_check_expr_deps(e->right.expr);
1099        case E_NOT:
1100                return sym_check_expr_deps(e->left.expr);
1101        case E_EQUAL:
1102        case E_GEQ:
1103        case E_GTH:
1104        case E_LEQ:
1105        case E_LTH:
1106        case E_UNEQUAL:
1107                sym = sym_check_deps(e->left.sym);
1108                if (sym)
1109                        return sym;
1110                return sym_check_deps(e->right.sym);
1111        case E_SYMBOL:
1112                return sym_check_deps(e->left.sym);
1113        default:
1114                break;
1115        }
1116        fprintf(stderr, "Oops! How to check %d?\n", e->type);
1117        return NULL;
1118}
1119
1120/* return NULL when dependencies are OK */
1121static struct symbol *sym_check_sym_deps(struct symbol *sym)
1122{
1123        struct symbol *sym2;
1124        struct property *prop;
1125        struct dep_stack stack;
1126
1127        dep_stack_insert(&stack, sym);
1128
1129        stack.expr = &sym->dir_dep.expr;
1130        sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1131        if (sym2)
1132                goto out;
1133
1134        stack.expr = &sym->rev_dep.expr;
1135        sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1136        if (sym2)
1137                goto out;
1138
1139        stack.expr = &sym->implied.expr;
1140        sym2 = sym_check_expr_deps(sym->implied.expr);
1141        if (sym2)
1142                goto out;
1143
1144        stack.expr = NULL;
1145
1146        for (prop = sym->prop; prop; prop = prop->next) {
1147                if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1148                    prop->type == P_IMPLY)
1149                        continue;
1150                stack.prop = prop;
1151                sym2 = sym_check_expr_deps(prop->visible.expr);
1152                if (sym2)
1153                        break;
1154                if (prop->type != P_DEFAULT || sym_is_choice(sym))
1155                        continue;
1156                stack.expr = &prop->expr;
1157                sym2 = sym_check_expr_deps(prop->expr);
1158                if (sym2)
1159                        break;
1160                stack.expr = NULL;
1161        }
1162
1163out:
1164        dep_stack_remove();
1165
1166        return sym2;
1167}
1168
1169static struct symbol *sym_check_choice_deps(struct symbol *choice)
1170{
1171        struct symbol *sym, *sym2;
1172        struct property *prop;
1173        struct expr *e;
1174        struct dep_stack stack;
1175
1176        dep_stack_insert(&stack, choice);
1177
1178        prop = sym_get_choice_prop(choice);
1179        expr_list_for_each_sym(prop->expr, e, sym)
1180                sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1181
1182        choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1183        sym2 = sym_check_sym_deps(choice);
1184        choice->flags &= ~SYMBOL_CHECK;
1185        if (sym2)
1186                goto out;
1187
1188        expr_list_for_each_sym(prop->expr, e, sym) {
1189                sym2 = sym_check_sym_deps(sym);
1190                if (sym2)
1191                        break;
1192        }
1193out:
1194        expr_list_for_each_sym(prop->expr, e, sym)
1195                sym->flags &= ~SYMBOL_CHECK;
1196
1197        if (sym2 && sym_is_choice_value(sym2) &&
1198            prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1199                sym2 = choice;
1200
1201        dep_stack_remove();
1202
1203        return sym2;
1204}
1205
1206struct symbol *sym_check_deps(struct symbol *sym)
1207{
1208        struct symbol *sym2;
1209        struct property *prop;
1210
1211        if (sym->flags & SYMBOL_CHECK) {
1212                sym_check_print_recursive(sym);
1213                return sym;
1214        }
1215        if (sym->flags & SYMBOL_CHECKED)
1216                return NULL;
1217
1218        if (sym_is_choice_value(sym)) {
1219                struct dep_stack stack;
1220
1221                /* for choice groups start the check with main choice symbol */
1222                dep_stack_insert(&stack, sym);
1223                prop = sym_get_choice_prop(sym);
1224                sym2 = sym_check_deps(prop_get_symbol(prop));
1225                dep_stack_remove();
1226        } else if (sym_is_choice(sym)) {
1227                sym2 = sym_check_choice_deps(sym);
1228        } else {
1229                sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1230                sym2 = sym_check_sym_deps(sym);
1231                sym->flags &= ~SYMBOL_CHECK;
1232        }
1233
1234        return sym2;
1235}
1236
1237struct symbol *prop_get_symbol(struct property *prop)
1238{
1239        if (prop->expr && (prop->expr->type == E_SYMBOL ||
1240                           prop->expr->type == E_LIST))
1241                return prop->expr->left.sym;
1242        return NULL;
1243}
1244
1245const char *prop_get_type_name(enum prop_type type)
1246{
1247        switch (type) {
1248        case P_PROMPT:
1249                return "prompt";
1250        case P_COMMENT:
1251                return "comment";
1252        case P_MENU:
1253                return "menu";
1254        case P_DEFAULT:
1255                return "default";
1256        case P_CHOICE:
1257                return "choice";
1258        case P_SELECT:
1259                return "select";
1260        case P_IMPLY:
1261                return "imply";
1262        case P_RANGE:
1263                return "range";
1264        case P_SYMBOL:
1265                return "symbol";
1266        case P_UNKNOWN:
1267                break;
1268        }
1269        return "unknown";
1270}
1271