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