scripts/kconfig/symbol.c

   1 /*
   2  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   3  * Released under the terms of the GNU GPL v2.0.
   4  */
   5
   6 #include <ctype.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <regex.h>
  10 #include <sys/utsname.h>
  11
  12 #include "lkc.h"
  13
  14 struct symbol symbol_yes = {
  15         .name = "y",
  16         .curr = { "y", yes },
  17         .flags = SYMBOL_CONST|SYMBOL_VALID,
  18 }, symbol_mod = {
  19         .name = "m",
  20         .curr = { "m", mod },
  21         .flags = SYMBOL_CONST|SYMBOL_VALID,
  22 }, symbol_no = {
  23         .name = "n",
  24         .curr = { "n", no },
  25         .flags = SYMBOL_CONST|SYMBOL_VALID,
  26 }, symbol_empty = {
  27         .name = "",
  28         .curr = { "", no },
  29         .flags = SYMBOL_VALID,
  30 };
  31
  32 struct symbol *sym_defconfig_list;
  33 struct symbol *modules_sym;
  34 tristate modules_val;
  35
  36 struct expr *sym_env_list;
  37
  38 static void sym_add_default(struct symbol *sym, const char *def)
  39 {
  40         struct property *prop = prop_alloc(P_DEFAULT, sym);
  41
  42         prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST));
  43 }
  44
  45 void sym_init(void)
  46 {
  47         struct symbol *sym;
  48         struct utsname uts;
  49         static bool inited = false;
  50
  51         if (inited)
  52                 return;
  53         inited = true;
  54
  55         uname(&uts);
  56
  57         sym = sym_lookup("UNAME_RELEASE", 0);
  58         sym->type = S_STRING;
  59         sym->flags |= SYMBOL_AUTO;
  60         sym_add_default(sym, uts.release);
  61 }
  62
  63 enum symbol_type sym_get_type(struct symbol *sym)
  64 {
  65         enum symbol_type type = sym->type;
  66
  67         if (type == S_TRISTATE) {
  68                 if (sym_is_choice_value(sym) && sym->visible == yes)
  69                         type = S_BOOLEAN;
  70                 else if (modules_val == no)
  71                         type = S_BOOLEAN;
  72         }
  73         return type;
  74 }
  75
  76 const char *sym_type_name(enum symbol_type type)
  77 {
  78         switch (type) {
  79         case S_BOOLEAN:
  80                 return "bool";
  81         case S_TRISTATE:
  82                 return "tristate";
  83         case S_INT:
  84                 return "integer";
  85         case S_HEX:
  86                 return "hex";
  87         case S_STRING:
  88                 return "string";
  89         case S_UNKNOWN:
  90                 return "unknown";
  91         case S_OTHER:
  92                 break;
  93         }
  94         return "???";
  95 }
  96
  97 struct property *sym_get_choice_prop(struct symbol *sym)
  98 {
  99         struct property *prop;
 100
 101         for_all_choices(sym, prop)
 102                 return prop;
 103         return NULL;
 104 }
 105
 106 struct property *sym_get_env_prop(struct symbol *sym)
 107 {
 108         struct property *prop;
 109
 110         for_all_properties(sym, prop, P_ENV)
 111                 return prop;
 112         return NULL;
 113 }
 114
 115 static struct property *sym_get_default_prop(struct symbol *sym)
 116 {
 117         struct property *prop;
 118
 119         for_all_defaults(sym, prop) {
 120                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 121                 if (prop->visible.tri != no)
 122                         return prop;
 123         }
 124         return NULL;
 125 }
 126
 127 static struct property *sym_get_range_prop(struct symbol *sym)
 128 {
 129         struct property *prop;
 130
 131         for_all_properties(sym, prop, P_RANGE) {
 132                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 133                 if (prop->visible.tri != no)
 134                         return prop;
 135         }
 136         return NULL;
 137 }
 138
 139 static long long sym_get_range_val(struct symbol *sym, int base)
 140 {
 141         sym_calc_value(sym);
 142         switch (sym->type) {
 143         case S_INT:
 144                 base = 10;
 145                 break;
 146         case S_HEX:
 147                 base = 16;
 148                 break;
 149         default:
 150                 break;
 151         }
 152         return strtoll(sym->curr.val, NULL, base);
 153 }
 154
 155 static void sym_validate_range(struct symbol *sym)
 156 {
 157         struct property *prop;
 158         int base;
 159         long long val, val2;
 160         char str[64];
 161
 162         switch (sym->type) {
 163         case S_INT:
 164                 base = 10;
 165                 break;
 166         case S_HEX:
 167                 base = 16;
 168                 break;
 169         default:
 170                 return;
 171         }
 172         prop = sym_get_range_prop(sym);
 173         if (!prop)
 174                 return;
 175         val = strtoll(sym->curr.val, NULL, base);
 176         val2 = sym_get_range_val(prop->expr->left.sym, base);
 177         if (val >= val2) {
 178                 val2 = sym_get_range_val(prop->expr->right.sym, base);
 179                 if (val <= val2)
 180                         return;
 181         }
 182         if (sym->type == S_INT)
 183                 sprintf(str, "%lld", val2);
 184         else
 185                 sprintf(str, "0x%llx", val2);
 186         sym->curr.val = xstrdup(str);
 187 }
 188
 189 static void sym_set_changed(struct symbol *sym)
 190 {
 191         struct property *prop;
 192
 193         sym->flags |= SYMBOL_CHANGED;
 194         for (prop = sym->prop; prop; prop = prop->next) {
 195                 if (prop->menu)
 196                         prop->menu->flags |= MENU_CHANGED;
 197         }
 198 }
 199
 200 static void sym_set_all_changed(void)
 201 {
 202         struct symbol *sym;
 203         int i;
 204
 205         for_all_symbols(i, sym)
 206                 sym_set_changed(sym);
 207 }
 208
 209 static void sym_calc_visibility(struct symbol *sym)
 210 {
 211         struct property *prop;
 212         struct symbol *choice_sym = NULL;
 213         tristate tri;
 214
 215         /* any prompt visible? */
 216         tri = no;
 217
 218         if (sym_is_choice_value(sym))
 219                 choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 220
 221         for_all_prompts(sym, prop) {
 222                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 223                 /*
 224                  * Tristate choice_values with visibility 'mod' are
 225                  * not visible if the corresponding choice's value is
 226                  * 'yes'.
 227                  */
 228                 if (choice_sym && sym->type == S_TRISTATE &&
 229                     prop->visible.tri == mod && choice_sym->curr.tri == yes)
 230                         prop->visible.tri = no;
 231
 232                 tri = EXPR_OR(tri, prop->visible.tri);
 233         }
 234         if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 235                 tri = yes;
 236         if (sym->visible != tri) {
 237                 sym->visible = tri;
 238                 sym_set_changed(sym);
 239         }
 240         if (sym_is_choice_value(sym))
 241                 return;
 242         /* defaulting to "yes" if no explicit "depends on" are given */
 243         tri = yes;
 244         if (sym->dir_dep.expr)
 245                 tri = expr_calc_value(sym->dir_dep.expr);
 246         if (tri == mod)
 247                 tri = yes;
 248         if (sym->dir_dep.tri != tri) {
 249                 sym->dir_dep.tri = tri;
 250                 sym_set_changed(sym);
 251         }
 252         tri = no;
 253         if (sym->rev_dep.expr)
 254                 tri = expr_calc_value(sym->rev_dep.expr);
 255         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 256                 tri = yes;
 257         if (sym->rev_dep.tri != tri) {
 258                 sym->rev_dep.tri = tri;
 259                 sym_set_changed(sym);
 260         }
 261         tri = no;
 262         if (sym->implied.expr && sym->dir_dep.tri != no)
 263                 tri = expr_calc_value(sym->implied.expr);
 264         if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 265                 tri = yes;
 266         if (sym->implied.tri != tri) {
 267                 sym->implied.tri = tri;
 268                 sym_set_changed(sym);
 269         }
 270 }
 271
 272 /*
 273  * Find the default symbol for a choice.
 274  * First try the default values for the choice symbol
 275  * Next locate the first visible choice value
 276  * Return NULL if none was found
 277  */
 278 struct symbol *sym_choice_default(struct symbol *sym)
 279 {
 280         struct symbol *def_sym;
 281         struct property *prop;
 282         struct expr *e;
 283
 284         /* any of the defaults visible? */
 285         for_all_defaults(sym, prop) {
 286                 prop->visible.tri = expr_calc_value(prop->visible.expr);
 287                 if (prop->visible.tri == no)
 288                         continue;
 289                 def_sym = prop_get_symbol(prop);
 290                 if (def_sym->visible != no)
 291                         return def_sym;
 292         }
 293
 294         /* just get the first visible value */
 295         prop = sym_get_choice_prop(sym);
 296         expr_list_for_each_sym(prop->expr, e, def_sym)
 297                 if (def_sym->visible != no)
 298                         return def_sym;
 299
 300         /* failed to locate any defaults */
 301         return NULL;
 302 }
 303
 304 static struct symbol *sym_calc_choice(struct symbol *sym)
 305 {
 306         struct symbol *def_sym;
 307         struct property *prop;
 308         struct expr *e;
 309         int flags;
 310
 311         /* first calculate all choice values' visibilities */
 312         flags = sym->flags;
 313         prop = sym_get_choice_prop(sym);
 314         expr_list_for_each_sym(prop->expr, e, def_sym) {
 315                 sym_calc_visibility(def_sym);
 316                 if (def_sym->visible != no)
 317                         flags &= def_sym->flags;
 318         }
 319
 320         sym->flags &= flags | ~SYMBOL_DEF_USER;
 321
 322         /* is the user choice visible? */
 323         def_sym = sym->def[S_DEF_USER].val;
 324         if (def_sym && def_sym->visible != no)
 325                 return def_sym;
 326
 327         def_sym = sym_choice_default(sym);
 328
 329         if (def_sym == NULL)
 330                 /* no choice? reset tristate value */
 331                 sym->curr.tri = no;
 332
 333         return def_sym;
 334 }
 335
 336 void sym_calc_value(struct symbol *sym)
 337 {
 338         struct symbol_value newval, oldval;
 339         struct property *prop;
 340         struct expr *e;
 341
 342         if (!sym)
 343                 return;
 344
 345         if (sym->flags & SYMBOL_VALID)
 346                 return;
 347
 348         if (sym_is_choice_value(sym) &&
 349             sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 350                 sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 351                 prop = sym_get_choice_prop(sym);
 352                 sym_calc_value(prop_get_symbol(prop));
 353         }
 354
 355         sym->flags |= SYMBOL_VALID;
 356
 357         oldval = sym->curr;
 358
 359         switch (sym->type) {
 360         case S_INT:
 361         case S_HEX:
 362         case S_STRING:
 363                 newval = symbol_empty.curr;
 364                 break;
 365         case S_BOOLEAN:
 366         case S_TRISTATE:
 367                 newval = symbol_no.curr;
 368                 break;
 369         default:
 370                 sym->curr.val = sym->name;
 371                 sym->curr.tri = no;
 372                 return;
 373         }
 374         sym->flags &= ~SYMBOL_WRITE;
 375
 376         sym_calc_visibility(sym);
 377
 378         if (sym->visible != no)
 379                 sym->flags |= SYMBOL_WRITE;
 380
 381         /* set default if recursively called */
 382         sym->curr = newval;
 383
 384         switch (sym_get_type(sym)) {
 385         case S_BOOLEAN:
 386         case S_TRISTATE:
 387                 if (sym_is_choice_value(sym) && sym->visible == yes) {
 388                         prop = sym_get_choice_prop(sym);
 389                         newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 390                 } else {
 391                         if (sym->visible != no) {
 392                                 /* if the symbol is visible use the user value
 393                                  * if available, otherwise try the default value
 394                                  */
 395                                 if (sym_has_value(sym)) {
 396                                         newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 397                                                               sym->visible);
 398                                         goto calc_newval;
 399                                 }
 400                         }
 401                         if (sym->rev_dep.tri != no)
 402                                 sym->flags |= SYMBOL_WRITE;
 403                         if (!sym_is_choice(sym)) {
 404                                 prop = sym_get_default_prop(sym);
 405                                 if (prop) {
 406                                         sym->flags |= SYMBOL_WRITE;
 407                                         newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 408                                                               prop->visible.tri);
 409                                 }
 410                                 if (sym->implied.tri != no) {
 411                                         sym->flags |= SYMBOL_WRITE;
 412                                         newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 413                                 }
 414                         }
 415                 calc_newval:
 416                         if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
 417                                 struct expr *e;
 418                                 e = expr_simplify_unmet_dep(sym->rev_dep.expr,
 419                                     sym->dir_dep.expr);
 420                                 fprintf(stderr, "warning: (");
 421                                 expr_fprint(e, stderr);
 422                                 fprintf(stderr, ") selects %s which has unmet direct dependencies (",
 423                                         sym->name);
 424                                 expr_fprint(sym->dir_dep.expr, stderr);
 425                                 fprintf(stderr, ")\n");
 426                                 expr_free(e);
 427                         }
 428                         newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 429                 }
 430                 if (newval.tri == mod &&
 431                     (sym_get_type(sym) == S_BOOLEAN || sym->implied.tri == yes))
 432                         newval.tri = yes;
 433                 break;
 434         case S_STRING:
 435         case S_HEX:
 436         case S_INT:
 437                 if (sym->visible != no && sym_has_value(sym)) {
 438                         newval.val = sym->def[S_DEF_USER].val;
 439                         break;
 440                 }
 441                 prop = sym_get_default_prop(sym);
 442                 if (prop) {
 443                         struct symbol *ds = prop_get_symbol(prop);
 444                         if (ds) {
 445                                 sym->flags |= SYMBOL_WRITE;
 446                                 sym_calc_value(ds);
 447                                 newval.val = ds->curr.val;
 448                         }
 449                 }
 450                 break;
 451         default:
 452                 ;
 453         }
 454
 455         sym->curr = newval;
 456         if (sym_is_choice(sym) && newval.tri == yes)
 457                 sym->curr.val = sym_calc_choice(sym);
 458         sym_validate_range(sym);
 459
 460         if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 461                 sym_set_changed(sym);
 462                 if (modules_sym == sym) {
 463                         sym_set_all_changed();
 464                         modules_val = modules_sym->curr.tri;
 465                 }
 466         }
 467
 468         if (sym_is_choice(sym)) {
 469                 struct symbol *choice_sym;
 470
 471                 prop = sym_get_choice_prop(sym);
 472                 expr_list_for_each_sym(prop->expr, e, choice_sym) {
 473                         if ((sym->flags & SYMBOL_WRITE) &&
 474                             choice_sym->visible != no)
 475                                 choice_sym->flags |= SYMBOL_WRITE;
 476                         if (sym->flags & SYMBOL_CHANGED)
 477                                 sym_set_changed(choice_sym);
 478                 }
 479         }
 480
 481         if (sym->flags & SYMBOL_AUTO)
 482                 sym->flags &= ~SYMBOL_WRITE;
 483
 484         if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 485                 set_all_choice_values(sym);
 486 }
 487
 488 void sym_clear_all_valid(void)
 489 {
 490         struct symbol *sym;
 491         int i;
 492
 493         for_all_symbols(i, sym)
 494                 sym->flags &= ~SYMBOL_VALID;
 495         sym_add_change_count(1);
 496         sym_calc_value(modules_sym);
 497 }
 498
 499 bool sym_tristate_within_range(struct symbol *sym, tristate val)
 500 {
 501         int type = sym_get_type(sym);
 502
 503         if (sym->visible == no)
 504                 return false;
 505
 506         if (type != S_BOOLEAN && type != S_TRISTATE)
 507                 return false;
 508
 509         if (type == S_BOOLEAN && val == mod)
 510                 return false;
 511         if (sym->visible <= sym->rev_dep.tri)
 512                 return false;
 513         if (sym->implied.tri == yes && val == mod)
 514                 return false;
 515         if (sym_is_choice_value(sym) && sym->visible == yes)
 516                 return val == yes;
 517         return val >= sym->rev_dep.tri && val <= sym->visible;
 518 }
 519
 520 bool sym_set_tristate_value(struct symbol *sym, tristate val)
 521 {
 522         tristate oldval = sym_get_tristate_value(sym);
 523
 524         if (oldval != val && !sym_tristate_within_range(sym, val))
 525                 return false;
 526
 527         if (!(sym->flags & SYMBOL_DEF_USER)) {
 528                 sym->flags |= SYMBOL_DEF_USER;
 529                 sym_set_changed(sym);
 530         }
 531         /*
 532          * setting a choice value also resets the new flag of the choice
 533          * symbol and all other choice values.
 534          */
 535         if (sym_is_choice_value(sym) && val == yes) {
 536                 struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 537                 struct property *prop;
 538                 struct expr *e;
 539
 540                 cs->def[S_DEF_USER].val = sym;
 541                 cs->flags |= SYMBOL_DEF_USER;
 542                 prop = sym_get_choice_prop(cs);
 543                 for (e = prop->expr; e; e = e->left.expr) {
 544                         if (e->right.sym->visible != no)
 545                                 e->right.sym->flags |= SYMBOL_DEF_USER;
 546                 }
 547         }
 548
 549         sym->def[S_DEF_USER].tri = val;
 550         if (oldval != val)
 551                 sym_clear_all_valid();
 552
 553         return true;
 554 }
 555
 556 tristate sym_toggle_tristate_value(struct symbol *sym)
 557 {
 558         tristate oldval, newval;
 559
 560         oldval = newval = sym_get_tristate_value(sym);
 561         do {
 562                 switch (newval) {
 563                 case no:
 564                         newval = mod;
 565                         break;
 566                 case mod:
 567                         newval = yes;
 568                         break;
 569                 case yes:
 570                         newval = no;
 571                         break;
 572                 }
 573                 if (sym_set_tristate_value(sym, newval))
 574                         break;
 575         } while (oldval != newval);
 576         return newval;
 577 }
 578
 579 bool sym_string_valid(struct symbol *sym, const char *str)
 580 {
 581         signed char ch;
 582
 583         switch (sym->type) {
 584         case S_STRING:
 585                 return true;
 586         case S_INT:
 587                 ch = *str++;
 588                 if (ch == '-')
 589                         ch = *str++;
 590                 if (!isdigit(ch))
 591                         return false;
 592                 if (ch == '0' && *str != 0)
 593                         return false;
 594                 while ((ch = *str++)) {
 595                         if (!isdigit(ch))
 596                                 return false;
 597                 }
 598                 return true;
 599         case S_HEX:
 600                 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 601                         str += 2;
 602                 ch = *str++;
 603                 do {
 604                         if (!isxdigit(ch))
 605                                 return false;
 606                 } while ((ch = *str++));
 607                 return true;
 608         case S_BOOLEAN:
 609         case S_TRISTATE:
 610                 switch (str[0]) {
 611                 case 'y': case 'Y':
 612                 case 'm': case 'M':
 613                 case 'n': case 'N':
 614                         return true;
 615                 }
 616                 return false;
 617         default:
 618                 return false;
 619         }
 620 }
 621
 622 bool sym_string_within_range(struct symbol *sym, const char *str)
 623 {
 624         struct property *prop;
 625         long long val;
 626
 627         switch (sym->type) {
 628         case S_STRING:
 629                 return sym_string_valid(sym, str);
 630         case S_INT:
 631                 if (!sym_string_valid(sym, str))
 632                         return false;
 633                 prop = sym_get_range_prop(sym);
 634                 if (!prop)
 635                         return true;
 636                 val = strtoll(str, NULL, 10);
 637                 return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 638                        val <= sym_get_range_val(prop->expr->right.sym, 10);
 639         case S_HEX:
 640                 if (!sym_string_valid(sym, str))
 641                         return false;
 642                 prop = sym_get_range_prop(sym);
 643                 if (!prop)
 644                         return true;
 645                 val = strtoll(str, NULL, 16);
 646                 return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 647                        val <= sym_get_range_val(prop->expr->right.sym, 16);
 648         case S_BOOLEAN:
 649         case S_TRISTATE:
 650                 switch (str[0]) {
 651                 case 'y': case 'Y':
 652                         return sym_tristate_within_range(sym, yes);
 653                 case 'm': case 'M':
 654                         return sym_tristate_within_range(sym, mod);
 655                 case 'n': case 'N':
 656                         return sym_tristate_within_range(sym, no);
 657                 }
 658                 return false;
 659         default:
 660                 return false;
 661         }
 662 }
 663
 664 bool sym_set_string_value(struct symbol *sym, const char *newval)
 665 {
 666         const char *oldval;
 667         char *val;
 668         int size;
 669
 670         switch (sym->type) {
 671         case S_BOOLEAN:
 672         case S_TRISTATE:
 673                 switch (newval[0]) {
 674                 case 'y': case 'Y':
 675                         return sym_set_tristate_value(sym, yes);
 676                 case 'm': case 'M':
 677                         return sym_set_tristate_value(sym, mod);
 678                 case 'n': case 'N':
 679                         return sym_set_tristate_value(sym, no);
 680                 }
 681                 return false;
 682         default:
 683                 ;
 684         }
 685
 686         if (!sym_string_within_range(sym, newval))
 687                 return false;
 688
 689         if (!(sym->flags & SYMBOL_DEF_USER)) {
 690                 sym->flags |= SYMBOL_DEF_USER;
 691                 sym_set_changed(sym);
 692         }
 693
 694         oldval = sym->def[S_DEF_USER].val;
 695         size = strlen(newval) + 1;
 696         if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 697                 size += 2;
 698                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 699                 *val++ = '0';
 700                 *val++ = 'x';
 701         } else if (!oldval || strcmp(oldval, newval))
 702                 sym->def[S_DEF_USER].val = val = xmalloc(size);
 703         else
 704                 return true;
 705
 706         strcpy(val, newval);
 707         free((void *)oldval);
 708         sym_clear_all_valid();
 709
 710         return true;
 711 }
 712
 713 /*
 714  * Find the default value associated to a symbol.
 715  * For tristate symbol handle the modules=n case
 716  * in which case "m" becomes "y".
 717  * If the symbol does not have any default then fallback
 718  * to the fixed default values.
 719  */
 720 const char *sym_get_string_default(struct symbol *sym)
 721 {
 722         struct property *prop;
 723         struct symbol *ds;
 724         const char *str;
 725         tristate val;
 726
 727         sym_calc_visibility(sym);
 728         sym_calc_value(modules_sym);
 729         val = symbol_no.curr.tri;
 730         str = symbol_empty.curr.val;
 731
 732         /* If symbol has a default value look it up */
 733         prop = sym_get_default_prop(sym);
 734         if (prop != NULL) {
 735                 switch (sym->type) {
 736                 case S_BOOLEAN:
 737                 case S_TRISTATE:
 738                         /* The visibility may limit the value from yes => mod */
 739                         val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 740                         break;
 741                 default:
 742                         /*
 743                          * The following fails to handle the situation
 744                          * where a default value is further limited by
 745                          * the valid range.
 746                          */
 747                         ds = prop_get_symbol(prop);
 748                         if (ds != NULL) {
 749                                 sym_calc_value(ds);
 750                                 str = (const char *)ds->curr.val;
 751                         }
 752                 }
 753         }
 754
 755         /* Handle select statements */
 756         val = EXPR_OR(val, sym->rev_dep.tri);
 757
 758         /* transpose mod to yes if modules are not enabled */
 759         if (val == mod)
 760                 if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 761                         val = yes;
 762
 763         /* transpose mod to yes if type is bool */
 764         if (sym->type == S_BOOLEAN && val == mod)
 765                 val = yes;
 766
 767         /* adjust the default value if this symbol is implied by another */
 768         if (val < sym->implied.tri)
 769                 val = sym->implied.tri;
 770
 771         switch (sym->type) {
 772         case S_BOOLEAN:
 773         case S_TRISTATE:
 774                 switch (val) {
 775                 case no: return "n";
 776                 case mod: return "m";
 777                 case yes: return "y";
 778                 }
 779         case S_INT:
 780         case S_HEX:
 781                 return str;
 782         case S_STRING:
 783                 return str;
 784         case S_OTHER:
 785         case S_UNKNOWN:
 786                 break;
 787         }
 788         return "";
 789 }
 790
 791 const char *sym_get_string_value(struct symbol *sym)
 792 {
 793         tristate val;
 794
 795         switch (sym->type) {
 796         case S_BOOLEAN:
 797         case S_TRISTATE:
 798                 val = sym_get_tristate_value(sym);
 799                 switch (val) {
 800                 case no:
 801                         return "n";
 802                 case mod:
 803                         sym_calc_value(modules_sym);
 804                         return (modules_sym->curr.tri == no) ? "n" : "m";
 805                 case yes:
 806                         return "y";
 807                 }
 808                 break;
 809         default:
 810                 ;
 811         }
 812         return (const char *)sym->curr.val;
 813 }
 814
 815 bool sym_is_changable(struct symbol *sym)
 816 {
 817         return sym->visible > sym->rev_dep.tri;
 818 }
 819
 820 static unsigned strhash(const char *s)
 821 {
 822         /* fnv32 hash */
 823         unsigned hash = 2166136261U;
 824         for (; *s; s++)
 825                 hash = (hash ^ *s) * 0x01000193;
 826         return hash;
 827 }
 828
 829 struct symbol *sym_lookup(const char *name, int flags)
 830 {
 831         struct symbol *symbol;
 832         char *new_name;
 833         int hash;
 834
 835         if (name) {
 836                 if (name[0] && !name[1]) {
 837                         switch (name[0]) {
 838                         case 'y': return &symbol_yes;
 839                         case 'm': return &symbol_mod;
 840                         case 'n': return &symbol_no;
 841                         }
 842                 }
 843                 hash = strhash(name) % SYMBOL_HASHSIZE;
 844
 845                 for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 846                         if (symbol->name &&
 847                             !strcmp(symbol->name, name) &&
 848                             (flags ? symbol->flags & flags
 849                                    : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 850                                 return symbol;
 851                 }
 852                 new_name = xstrdup(name);
 853         } else {
 854                 new_name = NULL;
 855                 hash = 0;
 856         }
 857
 858         symbol = xmalloc(sizeof(*symbol));
 859         memset(symbol, 0, sizeof(*symbol));
 860         symbol->name = new_name;
 861         symbol->type = S_UNKNOWN;
 862         symbol->flags |= flags;
 863
 864         symbol->next = symbol_hash[hash];
 865         symbol_hash[hash] = symbol;
 866
 867         return symbol;
 868 }
 869
 870 struct symbol *sym_find(const char *name)
 871 {
 872         struct symbol *symbol = NULL;
 873         int hash = 0;
 874
 875         if (!name)
 876                 return NULL;
 877
 878         if (name[0] && !name[1]) {
 879                 switch (name[0]) {
 880                 case 'y': return &symbol_yes;
 881                 case 'm': return &symbol_mod;
 882                 case 'n': return &symbol_no;
 883                 }
 884         }
 885         hash = strhash(name) % SYMBOL_HASHSIZE;
 886
 887         for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 888                 if (symbol->name &&
 889                     !strcmp(symbol->name, name) &&
 890                     !(symbol->flags & SYMBOL_CONST))
 891                                 break;
 892         }
 893
 894         return symbol;
 895 }
 896
 897 /*
 898  * Expand symbol's names embedded in the string given in argument. Symbols'
 899  * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
 900  * the empty string.
 901  */
 902 char *sym_expand_string_value(const char *in)
 903 {
 904         const char *src;
 905         char *res;
 906         size_t reslen;
 907
 908         /*
 909          * Note: 'in' might come from a token that's about to be
 910          * freed, so make sure to always allocate a new string
 911          */
 912         reslen = strlen(in) + 1;
 913         res = xmalloc(reslen);
 914         res[0] = '\0';
 915
 916         while ((src = strchr(in, '$'))) {
 917                 char *p, name[SYMBOL_MAXLENGTH];
 918                 const char *symval = "";
 919                 struct symbol *sym;
 920                 size_t newlen;
 921
 922                 strncat(res, in, src - in);
 923                 src++;
 924
 925                 p = name;
 926                 while (isalnum(*src) || *src == '_')
 927                         *p++ = *src++;
 928                 *p = '\0';
 929
 930                 sym = sym_find(name);
 931                 if (sym != NULL) {
 932                         sym_calc_value(sym);
 933                         symval = sym_get_string_value(sym);
 934                 }
 935
 936                 newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
 937                 if (newlen > reslen) {
 938                         reslen = newlen;
 939                         res = xrealloc(res, reslen);
 940                 }
 941
 942                 strcat(res, symval);
 943                 in = src;
 944         }
 945         strcat(res, in);
 946
 947         return res;
 948 }
 949
 950 const char *sym_escape_string_value(const char *in)
 951 {
 952         const char *p;
 953         size_t reslen;
 954         char *res;
 955         size_t l;
 956
 957         reslen = strlen(in) + strlen("\"\"") + 1;
 958
 959         p = in;
 960         for (;;) {
 961                 l = strcspn(p, "\"\\");
 962                 p += l;
 963
 964                 if (p[0] == '\0')
 965                         break;
 966
 967                 reslen++;
 968                 p++;
 969         }
 970
 971         res = xmalloc(reslen);
 972         res[0] = '\0';
 973
 974         strcat(res, "\"");
 975
 976         p = in;
 977         for (;;) {
 978                 l = strcspn(p, "\"\\");
 979                 strncat(res, p, l);
 980                 p += l;
 981
 982                 if (p[0] == '\0')
 983                         break;
 984
 985                 strcat(res, "\\");
 986                 strncat(res, p++, 1);
 987         }
 988
 989         strcat(res, "\"");
 990         return res;
 991 }
 992
 993 struct sym_match {
 994         struct symbol   *sym;
 995         off_t           so, eo;
 996 };
 997
 998 /* Compare matched symbols as thus:
 999  * - first, symbols that match exactly
1000  * - then, alphabetical sort
1001  */
1002 static int sym_rel_comp(const void *sym1, const void *sym2)
1003 {
1004         const struct sym_match *s1 = sym1;
1005         const struct sym_match *s2 = sym2;
1006         int exact1, exact2;
1007
1008         /* Exact match:
1009          * - if matched length on symbol s1 is the length of that symbol,
1010          *   then this symbol should come first;
1011          * - if matched length on symbol s2 is the length of that symbol,
1012          *   then this symbol should come first.
1013          * Note: since the search can be a regexp, both symbols may match
1014          * exactly; if this is the case, we can't decide which comes first,
1015          * and we fallback to sorting alphabetically.
1016          */
1017         exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
1018         exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
1019         if (exact1 && !exact2)
1020                 return -1;
1021         if (!exact1 && exact2)
1022                 return 1;
1023
1024         /* As a fallback, sort symbols alphabetically */
1025         return strcmp(s1->sym->name, s2->sym->name);
1026 }
1027
1028 struct symbol **sym_re_search(const char *pattern)
1029 {
1030         struct symbol *sym, **sym_arr = NULL;
1031         struct sym_match *sym_match_arr = NULL;
1032         int i, cnt, size;
1033         regex_t re;
1034         regmatch_t match[1];
1035
1036         cnt = size = 0;
1037         /* Skip if empty */
1038         if (strlen(pattern) == 0)
1039                 return NULL;
1040         if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
1041                 return NULL;
1042
1043         for_all_symbols(i, sym) {
1044                 if (sym->flags & SYMBOL_CONST || !sym->name)
1045                         continue;
1046                 if (regexec(&re, sym->name, 1, match, 0))
1047                         continue;
1048                 if (cnt >= size) {
1049                         void *tmp;
1050                         size += 16;
1051                         tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
1052                         if (!tmp)
1053                                 goto sym_re_search_free;
1054                         sym_match_arr = tmp;
1055                 }
1056                 sym_calc_value(sym);
1057                 /* As regexec returned 0, we know we have a match, so
1058                  * we can use match[0].rm_[se]o without further checks
1059                  */
1060                 sym_match_arr[cnt].so = match[0].rm_so;
1061                 sym_match_arr[cnt].eo = match[0].rm_eo;
1062                 sym_match_arr[cnt++].sym = sym;
1063         }
1064         if (sym_match_arr) {
1065                 qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
1066                 sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
1067                 if (!sym_arr)
1068                         goto sym_re_search_free;
1069                 for (i = 0; i < cnt; i++)
1070                         sym_arr[i] = sym_match_arr[i].sym;
1071                 sym_arr[cnt] = NULL;
1072         }
1073 sym_re_search_free:
1074         /* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1075         free(sym_match_arr);
1076         regfree(&re);
1077
1078         return sym_arr;
1079 }
1080
1081 /*
1082  * When we check for recursive dependencies we use a stack to save
1083  * current state so we can print out relevant info to user.
1084  * The entries are located on the call stack so no need to free memory.
1085  * Note insert() remove() must always match to properly clear the stack.
1086  */
1087 static struct dep_stack {
1088         struct dep_stack *prev, *next;
1089         struct symbol *sym;
1090         struct property *prop;
1091         struct expr *expr;
1092 } *check_top;
1093
1094 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1095 {
1096         memset(stack, 0, sizeof(*stack));
1097         if (check_top)
1098                 check_top->next = stack;
1099         stack->prev = check_top;
1100         stack->sym = sym;
1101         check_top = stack;
1102 }
1103
1104 static void dep_stack_remove(void)
1105 {
1106         check_top = check_top->prev;
1107         if (check_top)
1108                 check_top->next = NULL;
1109 }
1110
1111 /*
1112  * Called when we have detected a recursive dependency.
1113  * check_top point to the top of the stact so we use
1114  * the ->prev pointer to locate the bottom of the stack.
1115  */
1116 static void sym_check_print_recursive(struct symbol *last_sym)
1117 {
1118         struct dep_stack *stack;
1119         struct symbol *sym, *next_sym;
1120         struct menu *menu = NULL;
1121         struct property *prop;
1122         struct dep_stack cv_stack;
1123
1124         if (sym_is_choice_value(last_sym)) {
1125                 dep_stack_insert(&cv_stack, last_sym);
1126                 last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1127         }
1128
1129         for (stack = check_top; stack != NULL; stack = stack->prev)
1130                 if (stack->sym == last_sym)
1131                         break;
1132         if (!stack) {
1133                 fprintf(stderr, "unexpected recursive dependency error\n");
1134                 return;
1135         }
1136
1137         for (; stack; stack = stack->next) {
1138                 sym = stack->sym;
1139                 next_sym = stack->next ? stack->next->sym : last_sym;
1140                 prop = stack->prop;
1141                 if (prop == NULL)
1142                         prop = stack->sym->prop;
1143
1144                 /* for choice values find the menu entry (used below) */
1145                 if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1146                         for (prop = sym->prop; prop; prop = prop->next) {
1147                                 menu = prop->menu;
1148                                 if (prop->menu)
1149                                         break;
1150                         }
1151                 }
1152                 if (stack->sym == last_sym)
1153                         fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1154                                 prop->file->name, prop->lineno);
1155
1156                 if (stack->expr) {
1157                         fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1158                                 prop->file->name, prop->lineno,
1159                                 sym->name ? sym->name : "<choice>",
1160                                 prop_get_type_name(prop->type),
1161                                 next_sym->name ? next_sym->name : "<choice>");
1162                 } else if (stack->prop) {
1163                         fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1164                                 prop->file->name, prop->lineno,
1165                                 sym->name ? sym->name : "<choice>",
1166                                 next_sym->name ? next_sym->name : "<choice>");
1167                 } else if (sym_is_choice(sym)) {
1168                         fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1169                                 menu->file->name, menu->lineno,
1170                                 sym->name ? sym->name : "<choice>",
1171                                 next_sym->name ? next_sym->name : "<choice>");
1172                 } else if (sym_is_choice_value(sym)) {
1173                         fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1174                                 menu->file->name, menu->lineno,
1175                                 sym->name ? sym->name : "<choice>",
1176                                 next_sym->name ? next_sym->name : "<choice>");
1177                 } else {
1178                         fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1179                                 prop->file->name, prop->lineno,
1180                                 sym->name ? sym->name : "<choice>",
1181                                 next_sym->name ? next_sym->name : "<choice>");
1182                 }
1183         }
1184
1185         fprintf(stderr,
1186                 "For a resolution refer to Documentation/kbuild/kconfig-language.txt\n"
1187                 "subsection \"Kconfig recursive dependency limitations\"\n"
1188                 "\n");
1189
1190         if (check_top == &cv_stack)
1191                 dep_stack_remove();
1192 }
1193
1194 static struct symbol *sym_check_expr_deps(struct expr *e)
1195 {
1196         struct symbol *sym;
1197
1198         if (!e)
1199                 return NULL;
1200         switch (e->type) {
1201         case E_OR:
1202         case E_AND:
1203                 sym = sym_check_expr_deps(e->left.expr);
1204                 if (sym)
1205                         return sym;
1206                 return sym_check_expr_deps(e->right.expr);
1207         case E_NOT:
1208                 return sym_check_expr_deps(e->left.expr);
1209         case E_EQUAL:
1210         case E_GEQ:
1211         case E_GTH:
1212         case E_LEQ:
1213         case E_LTH:
1214         case E_UNEQUAL:
1215                 sym = sym_check_deps(e->left.sym);
1216                 if (sym)
1217                         return sym;
1218                 return sym_check_deps(e->right.sym);
1219         case E_SYMBOL:
1220                 return sym_check_deps(e->left.sym);
1221         default:
1222                 break;
1223         }
1224         fprintf(stderr, "Oops! How to check %d?\n", e->type);
1225         return NULL;
1226 }
1227
1228 /* return NULL when dependencies are OK */
1229 static struct symbol *sym_check_sym_deps(struct symbol *sym)
1230 {
1231         struct symbol *sym2;
1232         struct property *prop;
1233         struct dep_stack stack;
1234
1235         dep_stack_insert(&stack, sym);
1236
1237         sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1238         if (sym2)
1239                 goto out;
1240
1241         for (prop = sym->prop; prop; prop = prop->next) {
1242                 if (prop->type == P_CHOICE || prop->type == P_SELECT)
1243                         continue;
1244                 stack.prop = prop;
1245                 sym2 = sym_check_expr_deps(prop->visible.expr);
1246                 if (sym2)
1247                         break;
1248                 if (prop->type != P_DEFAULT || sym_is_choice(sym))
1249                         continue;
1250                 stack.expr = prop->expr;
1251                 sym2 = sym_check_expr_deps(prop->expr);
1252                 if (sym2)
1253                         break;
1254                 stack.expr = NULL;
1255         }
1256
1257 out:
1258         dep_stack_remove();
1259
1260         return sym2;
1261 }
1262
1263 static struct symbol *sym_check_choice_deps(struct symbol *choice)
1264 {
1265         struct symbol *sym, *sym2;
1266         struct property *prop;
1267         struct expr *e;
1268         struct dep_stack stack;
1269
1270         dep_stack_insert(&stack, choice);
1271
1272         prop = sym_get_choice_prop(choice);
1273         expr_list_for_each_sym(prop->expr, e, sym)
1274                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1275
1276         choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1277         sym2 = sym_check_sym_deps(choice);
1278         choice->flags &= ~SYMBOL_CHECK;
1279         if (sym2)
1280                 goto out;
1281
1282         expr_list_for_each_sym(prop->expr, e, sym) {
1283                 sym2 = sym_check_sym_deps(sym);
1284                 if (sym2)
1285                         break;
1286         }
1287 out:
1288         expr_list_for_each_sym(prop->expr, e, sym)
1289                 sym->flags &= ~SYMBOL_CHECK;
1290
1291         if (sym2 && sym_is_choice_value(sym2) &&
1292             prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1293                 sym2 = choice;
1294
1295         dep_stack_remove();
1296
1297         return sym2;
1298 }
1299
1300 struct symbol *sym_check_deps(struct symbol *sym)
1301 {
1302         struct symbol *sym2;
1303         struct property *prop;
1304
1305         if (sym->flags & SYMBOL_CHECK) {
1306                 sym_check_print_recursive(sym);
1307                 return sym;
1308         }
1309         if (sym->flags & SYMBOL_CHECKED)
1310                 return NULL;
1311
1312         if (sym_is_choice_value(sym)) {
1313                 struct dep_stack stack;
1314
1315                 /* for choice groups start the check with main choice symbol */
1316                 dep_stack_insert(&stack, sym);
1317                 prop = sym_get_choice_prop(sym);
1318                 sym2 = sym_check_deps(prop_get_symbol(prop));
1319                 dep_stack_remove();
1320         } else if (sym_is_choice(sym)) {
1321                 sym2 = sym_check_choice_deps(sym);
1322         } else {
1323                 sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1324                 sym2 = sym_check_sym_deps(sym);
1325                 sym->flags &= ~SYMBOL_CHECK;
1326         }
1327
1328         if (sym2 && sym2 == sym)
1329                 sym2 = NULL;
1330
1331         return sym2;
1332 }
1333
1334 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1335 {
1336         struct property *prop;
1337         struct property **propp;
1338
1339         prop = xmalloc(sizeof(*prop));
1340         memset(prop, 0, sizeof(*prop));
1341         prop->type = type;
1342         prop->sym = sym;
1343         prop->file = current_file;
1344         prop->lineno = zconf_lineno();
1345
1346         /* append property to the prop list of symbol */
1347         if (sym) {
1348                 for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1349                         ;
1350                 *propp = prop;
1351         }
1352
1353         return prop;
1354 }
1355
1356 struct symbol *prop_get_symbol(struct property *prop)
1357 {
1358         if (prop->expr && (prop->expr->type == E_SYMBOL ||
1359                            prop->expr->type == E_LIST))
1360                 return prop->expr->left.sym;
1361         return NULL;
1362 }
1363
1364 const char *prop_get_type_name(enum prop_type type)
1365 {
1366         switch (type) {
1367         case P_PROMPT:
1368                 return "prompt";
1369         case P_ENV:
1370                 return "env";
1371         case P_COMMENT:
1372                 return "comment";
1373         case P_MENU:
1374                 return "menu";
1375         case P_DEFAULT:
1376                 return "default";
1377         case P_CHOICE:
1378                 return "choice";
1379         case P_SELECT:
1380                 return "select";
1381         case P_IMPLY:
1382                 return "imply";
1383         case P_RANGE:
1384                 return "range";
1385         case P_SYMBOL:
1386                 return "symbol";
1387         case P_UNKNOWN:
1388                 break;
1389         }
1390         return "unknown";
1391 }
1392
1393 static void prop_add_env(const char *env)
1394 {
1395         struct symbol *sym, *sym2;
1396         struct property *prop;
1397         char *p;
1398
1399         sym = current_entry->sym;
1400         sym->flags |= SYMBOL_AUTO;
1401         for_all_properties(sym, prop, P_ENV) {
1402                 sym2 = prop_get_symbol(prop);
1403                 if (strcmp(sym2->name, env))
1404                         menu_warn(current_entry, "redefining environment symbol from %s",
1405                                   sym2->name);
1406                 return;
1407         }
1408
1409         prop = prop_alloc(P_ENV, sym);
1410         prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1411
1412         sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1413         sym_env_list->right.sym = sym;
1414
1415         p = getenv(env);
1416         if (p)
1417                 sym_add_default(sym, p);
1418         else
1419                 menu_warn(current_entry, "environment variable %s undefined", env);
1420 }