scripts/kconfig/menu.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   4  */
   5
   6 #include <ctype.h>
   7 #include <stdarg.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10
  11 #include "lkc.h"
  12
  13 static const char nohelp_text[] = "There is no help available for this option.";
  14
  15 struct menu rootmenu;
  16 static struct menu **last_entry_ptr;
  17
  18 struct file *file_list;
  19 struct file *current_file;
  20
  21 void menu_warn(struct menu *menu, const char *fmt, ...)
  22 {
  23         va_list ap;
  24         va_start(ap, fmt);
  25         fprintf(stderr, "%s:%d:warning: ", menu->file->name, menu->lineno);
  26         vfprintf(stderr, fmt, ap);
  27         fprintf(stderr, "\n");
  28         va_end(ap);
  29 }
  30
  31 static void prop_warn(struct property *prop, const char *fmt, ...)
  32 {
  33         va_list ap;
  34         va_start(ap, fmt);
  35         fprintf(stderr, "%s:%d:warning: ", prop->file->name, prop->lineno);
  36         vfprintf(stderr, fmt, ap);
  37         fprintf(stderr, "\n");
  38         va_end(ap);
  39 }
  40
  41 void _menu_init(void)
  42 {
  43         current_entry = current_menu = &rootmenu;
  44         last_entry_ptr = &rootmenu.list;
  45 }
  46
  47 void menu_add_entry(struct symbol *sym)
  48 {
  49         struct menu *menu;
  50
  51         menu = xmalloc(sizeof(*menu));
  52         memset(menu, 0, sizeof(*menu));
  53         menu->sym = sym;
  54         menu->parent = current_menu;
  55         menu->file = current_file;
  56         menu->lineno = zconf_lineno();
  57
  58         *last_entry_ptr = menu;
  59         last_entry_ptr = &menu->next;
  60         current_entry = menu;
  61         if (sym)
  62                 menu_add_symbol(P_SYMBOL, sym, NULL);
  63 }
  64
  65 struct menu *menu_add_menu(void)
  66 {
  67         last_entry_ptr = &current_entry->list;
  68         current_menu = current_entry;
  69         return current_menu;
  70 }
  71
  72 void menu_end_menu(void)
  73 {
  74         last_entry_ptr = &current_menu->next;
  75         current_menu = current_menu->parent;
  76 }
  77
  78 /*
  79  * Rewrites 'm' to 'm' && MODULES, so that it evaluates to 'n' when running
  80  * without modules
  81  */
  82 static struct expr *rewrite_m(struct expr *e)
  83 {
  84         if (!e)
  85                 return e;
  86
  87         switch (e->type) {
  88         case E_NOT:
  89                 e->left.expr = rewrite_m(e->left.expr);
  90                 break;
  91         case E_OR:
  92         case E_AND:
  93                 e->left.expr = rewrite_m(e->left.expr);
  94                 e->right.expr = rewrite_m(e->right.expr);
  95                 break;
  96         case E_SYMBOL:
  97                 /* change 'm' into 'm' && MODULES */
  98                 if (e->left.sym == &symbol_mod)
  99                         return expr_alloc_and(e, expr_alloc_symbol(modules_sym));
 100                 break;
 101         default:
 102                 break;
 103         }
 104         return e;
 105 }
 106
 107 void menu_add_dep(struct expr *dep)
 108 {
 109         current_entry->dep = expr_alloc_and(current_entry->dep, dep);
 110 }
 111
 112 void menu_set_type(int type)
 113 {
 114         struct symbol *sym = current_entry->sym;
 115
 116         if (sym->type == type)
 117                 return;
 118         if (sym->type == S_UNKNOWN) {
 119                 sym->type = type;
 120                 return;
 121         }
 122         menu_warn(current_entry,
 123                 "ignoring type redefinition of '%s' from '%s' to '%s'",
 124                 sym->name ? sym->name : "<choice>",
 125                 sym_type_name(sym->type), sym_type_name(type));
 126 }
 127
 128 static struct property *menu_add_prop(enum prop_type type, struct expr *expr,
 129                                       struct expr *dep)
 130 {
 131         struct property *prop;
 132
 133         prop = xmalloc(sizeof(*prop));
 134         memset(prop, 0, sizeof(*prop));
 135         prop->type = type;
 136         prop->file = current_file;
 137         prop->lineno = zconf_lineno();
 138         prop->menu = current_entry;
 139         prop->expr = expr;
 140         prop->visible.expr = dep;
 141
 142         /* append property to the prop list of symbol */
 143         if (current_entry->sym) {
 144                 struct property **propp;
 145
 146                 for (propp = &current_entry->sym->prop;
 147                      *propp;
 148                      propp = &(*propp)->next)
 149                         ;
 150                 *propp = prop;
 151         }
 152
 153         return prop;
 154 }
 155
 156 struct property *menu_add_prompt(enum prop_type type, char *prompt,
 157                                  struct expr *dep)
 158 {
 159         struct property *prop = menu_add_prop(type, NULL, dep);
 160
 161         if (isspace(*prompt)) {
 162                 prop_warn(prop, "leading whitespace ignored");
 163                 while (isspace(*prompt))
 164                         prompt++;
 165         }
 166         if (current_entry->prompt)
 167                 prop_warn(prop, "prompt redefined");
 168
 169         /* Apply all upper menus' visibilities to actual prompts. */
 170         if (type == P_PROMPT) {
 171                 struct menu *menu = current_entry;
 172
 173                 while ((menu = menu->parent) != NULL) {
 174                         struct expr *dup_expr;
 175
 176                         if (!menu->visibility)
 177                                 continue;
 178                         /*
 179                          * Do not add a reference to the menu's visibility
 180                          * expression but use a copy of it. Otherwise the
 181                          * expression reduction functions will modify
 182                          * expressions that have multiple references which
 183                          * can cause unwanted side effects.
 184                          */
 185                         dup_expr = expr_copy(menu->visibility);
 186
 187                         prop->visible.expr = expr_alloc_and(prop->visible.expr,
 188                                                             dup_expr);
 189                 }
 190         }
 191
 192         current_entry->prompt = prop;
 193         prop->text = prompt;
 194
 195         return prop;
 196 }
 197
 198 void menu_add_visibility(struct expr *expr)
 199 {
 200         current_entry->visibility = expr_alloc_and(current_entry->visibility,
 201             expr);
 202 }
 203
 204 void menu_add_expr(enum prop_type type, struct expr *expr, struct expr *dep)
 205 {
 206         menu_add_prop(type, expr, dep);
 207 }
 208
 209 void menu_add_symbol(enum prop_type type, struct symbol *sym, struct expr *dep)
 210 {
 211         menu_add_prop(type, expr_alloc_symbol(sym), dep);
 212 }
 213
 214 void menu_add_option_modules(void)
 215 {
 216         if (modules_sym)
 217                 zconf_error("symbol '%s' redefines option 'modules' already defined by symbol '%s'",
 218                             current_entry->sym->name, modules_sym->name);
 219         modules_sym = current_entry->sym;
 220 }
 221
 222 void menu_add_option_defconfig_list(void)
 223 {
 224         if (!sym_defconfig_list)
 225                 sym_defconfig_list = current_entry->sym;
 226         else if (sym_defconfig_list != current_entry->sym)
 227                 zconf_error("trying to redefine defconfig symbol");
 228         sym_defconfig_list->flags |= SYMBOL_NO_WRITE;
 229 }
 230
 231 void menu_add_option_allnoconfig_y(void)
 232 {
 233         current_entry->sym->flags |= SYMBOL_ALLNOCONFIG_Y;
 234 }
 235
 236 static int menu_validate_number(struct symbol *sym, struct symbol *sym2)
 237 {
 238         return sym2->type == S_INT || sym2->type == S_HEX ||
 239                (sym2->type == S_UNKNOWN && sym_string_valid(sym, sym2->name));
 240 }
 241
 242 static void sym_check_prop(struct symbol *sym)
 243 {
 244         struct property *prop;
 245         struct symbol *sym2;
 246         char *use;
 247
 248         for (prop = sym->prop; prop; prop = prop->next) {
 249                 switch (prop->type) {
 250                 case P_DEFAULT:
 251                         if ((sym->type == S_STRING || sym->type == S_INT || sym->type == S_HEX) &&
 252                             prop->expr->type != E_SYMBOL)
 253                                 prop_warn(prop,
 254                                     "default for config symbol '%s'"
 255                                     " must be a single symbol", sym->name);
 256                         if (prop->expr->type != E_SYMBOL)
 257                                 break;
 258                         sym2 = prop_get_symbol(prop);
 259                         if (sym->type == S_HEX || sym->type == S_INT) {
 260                                 if (!menu_validate_number(sym, sym2))
 261                                         prop_warn(prop,
 262                                             "'%s': number is invalid",
 263                                             sym->name);
 264                         }
 265                         if (sym_is_choice(sym)) {
 266                                 struct property *choice_prop =
 267                                         sym_get_choice_prop(sym2);
 268
 269                                 if (!choice_prop ||
 270                                     prop_get_symbol(choice_prop) != sym)
 271                                         prop_warn(prop,
 272                                                   "choice default symbol '%s' is not contained in the choice",
 273                                                   sym2->name);
 274                         }
 275                         break;
 276                 case P_SELECT:
 277                 case P_IMPLY:
 278                         use = prop->type == P_SELECT ? "select" : "imply";
 279                         sym2 = prop_get_symbol(prop);
 280                         if (sym->type != S_BOOLEAN && sym->type != S_TRISTATE)
 281                                 prop_warn(prop,
 282                                     "config symbol '%s' uses %s, but is "
 283                                     "not bool or tristate", sym->name, use);
 284                         else if (sym2->type != S_UNKNOWN &&
 285                                  sym2->type != S_BOOLEAN &&
 286                                  sym2->type != S_TRISTATE)
 287                                 prop_warn(prop,
 288                                     "'%s' has wrong type. '%s' only "
 289                                     "accept arguments of bool and "
 290                                     "tristate type", sym2->name, use);
 291                         break;
 292                 case P_RANGE:
 293                         if (sym->type != S_INT && sym->type != S_HEX)
 294                                 prop_warn(prop, "range is only allowed "
 295                                                 "for int or hex symbols");
 296                         if (!menu_validate_number(sym, prop->expr->left.sym) ||
 297                             !menu_validate_number(sym, prop->expr->right.sym))
 298                                 prop_warn(prop, "range is invalid");
 299                         break;
 300                 default:
 301                         ;
 302                 }
 303         }
 304 }
 305
 306 void menu_finalize(struct menu *parent)
 307 {
 308         struct menu *menu, *last_menu;
 309         struct symbol *sym;
 310         struct property *prop;
 311         struct expr *parentdep, *basedep, *dep, *dep2, **ep;
 312
 313         sym = parent->sym;
 314         if (parent->list) {
 315                 /*
 316                  * This menu node has children. We (recursively) process them
 317                  * and propagate parent dependencies before moving on.
 318                  */
 319
 320                 if (sym && sym_is_choice(sym)) {
 321                         if (sym->type == S_UNKNOWN) {
 322                                 /* find the first choice value to find out choice type */
 323                                 current_entry = parent;
 324                                 for (menu = parent->list; menu; menu = menu->next) {
 325                                         if (menu->sym && menu->sym->type != S_UNKNOWN) {
 326                                                 menu_set_type(menu->sym->type);
 327                                                 break;
 328                                         }
 329                                 }
 330                         }
 331                         /* set the type of the remaining choice values */
 332                         for (menu = parent->list; menu; menu = menu->next) {
 333                                 current_entry = menu;
 334                                 if (menu->sym && menu->sym->type == S_UNKNOWN)
 335                                         menu_set_type(sym->type);
 336                         }
 337
 338                         /*
 339                          * Use the choice itself as the parent dependency of
 340                          * the contained items. This turns the mode of the
 341                          * choice into an upper bound on the visibility of the
 342                          * choice value symbols.
 343                          */
 344                         parentdep = expr_alloc_symbol(sym);
 345                 } else {
 346                         /* Menu node for 'menu', 'if' */
 347                         parentdep = parent->dep;
 348                 }
 349
 350                 /* For each child menu node... */
 351                 for (menu = parent->list; menu; menu = menu->next) {
 352                         /*
 353                          * Propagate parent dependencies to the child menu
 354                          * node, also rewriting and simplifying expressions
 355                          */
 356                         basedep = rewrite_m(menu->dep);
 357                         basedep = expr_transform(basedep);
 358                         basedep = expr_alloc_and(expr_copy(parentdep), basedep);
 359                         basedep = expr_eliminate_dups(basedep);
 360                         menu->dep = basedep;
 361
 362                         if (menu->sym)
 363                                 /*
 364                                  * Note: For symbols, all prompts are included
 365                                  * too in the symbol's own property list
 366                                  */
 367                                 prop = menu->sym->prop;
 368                         else
 369                                 /*
 370                                  * For non-symbol menu nodes, we just need to
 371                                  * handle the prompt
 372                                  */
 373                                 prop = menu->prompt;
 374
 375                         /* For each property... */
 376                         for (; prop; prop = prop->next) {
 377                                 if (prop->menu != menu)
 378                                         /*
 379                                          * Two possibilities:
 380                                          *
 381                                          * 1. The property lacks dependencies
 382                                          *    and so isn't location-specific,
 383                                          *    e.g. an 'option'
 384                                          *
 385                                          * 2. The property belongs to a symbol
 386                                          *    defined in multiple locations and
 387                                          *    is from some other location. It
 388                                          *    will be handled there in that
 389                                          *    case.
 390                                          *
 391                                          * Skip the property.
 392                                          */
 393                                         continue;
 394
 395                                 /*
 396                                  * Propagate parent dependencies to the
 397                                  * property's condition, rewriting and
 398                                  * simplifying expressions at the same time
 399                                  */
 400                                 dep = rewrite_m(prop->visible.expr);
 401                                 dep = expr_transform(dep);
 402                                 dep = expr_alloc_and(expr_copy(basedep), dep);
 403                                 dep = expr_eliminate_dups(dep);
 404                                 if (menu->sym && menu->sym->type != S_TRISTATE)
 405                                         dep = expr_trans_bool(dep);
 406                                 prop->visible.expr = dep;
 407
 408                                 /*
 409                                  * Handle selects and implies, which modify the
 410                                  * dependencies of the selected/implied symbol
 411                                  */
 412                                 if (prop->type == P_SELECT) {
 413                                         struct symbol *es = prop_get_symbol(prop);
 414                                         es->rev_dep.expr = expr_alloc_or(es->rev_dep.expr,
 415                                                         expr_alloc_and(expr_alloc_symbol(menu->sym), expr_copy(dep)));
 416                                 } else if (prop->type == P_IMPLY) {
 417                                         struct symbol *es = prop_get_symbol(prop);
 418                                         es->implied.expr = expr_alloc_or(es->implied.expr,
 419                                                         expr_alloc_and(expr_alloc_symbol(menu->sym), expr_copy(dep)));
 420                                 }
 421                         }
 422                 }
 423
 424                 if (sym && sym_is_choice(sym))
 425                         expr_free(parentdep);
 426
 427                 /*
 428                  * Recursively process children in the same fashion before
 429                  * moving on
 430                  */
 431                 for (menu = parent->list; menu; menu = menu->next)
 432                         menu_finalize(menu);
 433         } else if (sym) {
 434                 /*
 435                  * Automatic submenu creation. If sym is a symbol and A, B, C,
 436                  * ... are consecutive items (symbols, menus, ifs, etc.) that
 437                  * all depend on sym, then the following menu structure is
 438                  * created:
 439                  *
 440                  *      sym
 441                  *       +-A
 442                  *       +-B
 443                  *       +-C
 444                  *       ...
 445                  *
 446                  * This also works recursively, giving the following structure
 447                  * if A is a symbol and B depends on A:
 448                  *
 449                  *      sym
 450                  *       +-A
 451                  *       | +-B
 452                  *       +-C
 453                  *       ...
 454                  */
 455
 456                 basedep = parent->prompt ? parent->prompt->visible.expr : NULL;
 457                 basedep = expr_trans_compare(basedep, E_UNEQUAL, &symbol_no);
 458                 basedep = expr_eliminate_dups(expr_transform(basedep));
 459
 460                 /* Examine consecutive elements after sym */
 461                 last_menu = NULL;
 462                 for (menu = parent->next; menu; menu = menu->next) {
 463                         dep = menu->prompt ? menu->prompt->visible.expr : menu->dep;
 464                         if (!expr_contains_symbol(dep, sym))
 465                                 /* No dependency, quit */
 466                                 break;
 467                         if (expr_depends_symbol(dep, sym))
 468                                 /* Absolute dependency, put in submenu */
 469                                 goto next;
 470
 471                         /*
 472                          * Also consider it a dependency on sym if our
 473                          * dependencies contain sym and are a "superset" of
 474                          * sym's dependencies, e.g. '(sym || Q) && R' when sym
 475                          * depends on R.
 476                          *
 477                          * Note that 'R' might be from an enclosing menu or if,
 478                          * making this a more common case than it might seem.
 479                          */
 480                         dep = expr_trans_compare(dep, E_UNEQUAL, &symbol_no);
 481                         dep = expr_eliminate_dups(expr_transform(dep));
 482                         dep2 = expr_copy(basedep);
 483                         expr_eliminate_eq(&dep, &dep2);
 484                         expr_free(dep);
 485                         if (!expr_is_yes(dep2)) {
 486                                 /* Not superset, quit */
 487                                 expr_free(dep2);
 488                                 break;
 489                         }
 490                         /* Superset, put in submenu */
 491                         expr_free(dep2);
 492                 next:
 493                         menu_finalize(menu);
 494                         menu->parent = parent;
 495                         last_menu = menu;
 496                 }
 497                 expr_free(basedep);
 498                 if (last_menu) {
 499                         parent->list = parent->next;
 500                         parent->next = last_menu->next;
 501                         last_menu->next = NULL;
 502                 }
 503
 504                 sym->dir_dep.expr = expr_alloc_or(sym->dir_dep.expr, parent->dep);
 505         }
 506         for (menu = parent->list; menu; menu = menu->next) {
 507                 if (sym && sym_is_choice(sym) &&
 508                     menu->sym && !sym_is_choice_value(menu->sym)) {
 509                         current_entry = menu;
 510                         menu->sym->flags |= SYMBOL_CHOICEVAL;
 511                         if (!menu->prompt)
 512                                 menu_warn(menu, "choice value must have a prompt");
 513                         for (prop = menu->sym->prop; prop; prop = prop->next) {
 514                                 if (prop->type == P_DEFAULT)
 515                                         prop_warn(prop, "defaults for choice "
 516                                                   "values not supported");
 517                                 if (prop->menu == menu)
 518                                         continue;
 519                                 if (prop->type == P_PROMPT &&
 520                                     prop->menu->parent->sym != sym)
 521                                         prop_warn(prop, "choice value used outside its choice group");
 522                         }
 523                         /* Non-tristate choice values of tristate choices must
 524                          * depend on the choice being set to Y. The choice
 525                          * values' dependencies were propagated to their
 526                          * properties above, so the change here must be re-
 527                          * propagated.
 528                          */
 529                         if (sym->type == S_TRISTATE && menu->sym->type != S_TRISTATE) {
 530                                 basedep = expr_alloc_comp(E_EQUAL, sym, &symbol_yes);
 531                                 menu->dep = expr_alloc_and(basedep, menu->dep);
 532                                 for (prop = menu->sym->prop; prop; prop = prop->next) {
 533                                         if (prop->menu != menu)
 534                                                 continue;
 535                                         prop->visible.expr = expr_alloc_and(expr_copy(basedep),
 536                                                                             prop->visible.expr);
 537                                 }
 538                         }
 539                         menu_add_symbol(P_CHOICE, sym, NULL);
 540                         prop = sym_get_choice_prop(sym);
 541                         for (ep = &prop->expr; *ep; ep = &(*ep)->left.expr)
 542                                 ;
 543                         *ep = expr_alloc_one(E_LIST, NULL);
 544                         (*ep)->right.sym = menu->sym;
 545                 }
 546
 547                 /*
 548                  * This code serves two purposes:
 549                  *
 550                  * (1) Flattening 'if' blocks, which do not specify a submenu
 551                  *     and only add dependencies.
 552                  *
 553                  *     (Automatic submenu creation might still create a submenu
 554                  *     from an 'if' before this code runs.)
 555                  *
 556                  * (2) "Undoing" any automatic submenus created earlier below
 557                  *     promptless symbols.
 558                  *
 559                  * Before:
 560                  *
 561                  *      A
 562                  *      if ... (or promptless symbol)
 563                  *       +-B
 564                  *       +-C
 565                  *      D
 566                  *
 567                  * After:
 568                  *
 569                  *      A
 570                  *      if ... (or promptless symbol)
 571                  *      B
 572                  *      C
 573                  *      D
 574                  */
 575                 if (menu->list && (!menu->prompt || !menu->prompt->text)) {
 576                         for (last_menu = menu->list; ; last_menu = last_menu->next) {
 577                                 last_menu->parent = parent;
 578                                 if (!last_menu->next)
 579                                         break;
 580                         }
 581                         last_menu->next = menu->next;
 582                         menu->next = menu->list;
 583                         menu->list = NULL;
 584                 }
 585         }
 586
 587         if (sym && !(sym->flags & SYMBOL_WARNED)) {
 588                 if (sym->type == S_UNKNOWN)
 589                         menu_warn(parent, "config symbol defined without type");
 590
 591                 if (sym_is_choice(sym) && !parent->prompt)
 592                         menu_warn(parent, "choice must have a prompt");
 593
 594                 /* Check properties connected to this symbol */
 595                 sym_check_prop(sym);
 596                 sym->flags |= SYMBOL_WARNED;
 597         }
 598
 599         /*
 600          * For non-optional choices, add a reverse dependency (corresponding to
 601          * a select) of '<visibility> && m'. This prevents the user from
 602          * setting the choice mode to 'n' when the choice is visible.
 603          *
 604          * This would also work for non-choice symbols, but only non-optional
 605          * choices clear SYMBOL_OPTIONAL as of writing. Choices are implemented
 606          * as a type of symbol.
 607          */
 608         if (sym && !sym_is_optional(sym) && parent->prompt) {
 609                 sym->rev_dep.expr = expr_alloc_or(sym->rev_dep.expr,
 610                                 expr_alloc_and(parent->prompt->visible.expr,
 611                                         expr_alloc_symbol(&symbol_mod)));
 612         }
 613 }
 614
 615 bool menu_has_prompt(struct menu *menu)
 616 {
 617         if (!menu->prompt)
 618                 return false;
 619         return true;
 620 }
 621
 622 /*
 623  * Determine if a menu is empty.
 624  * A menu is considered empty if it contains no or only
 625  * invisible entries.
 626  */
 627 bool menu_is_empty(struct menu *menu)
 628 {
 629         struct menu *child;
 630
 631         for (child = menu->list; child; child = child->next) {
 632                 if (menu_is_visible(child))
 633                         return(false);
 634         }
 635         return(true);
 636 }
 637
 638 bool menu_is_visible(struct menu *menu)
 639 {
 640         struct menu *child;
 641         struct symbol *sym;
 642         tristate visible;
 643
 644         if (!menu->prompt)
 645                 return false;
 646
 647         if (menu->visibility) {
 648                 if (expr_calc_value(menu->visibility) == no)
 649                         return false;
 650         }
 651
 652         sym = menu->sym;
 653         if (sym) {
 654                 sym_calc_value(sym);
 655                 visible = menu->prompt->visible.tri;
 656         } else
 657                 visible = menu->prompt->visible.tri = expr_calc_value(menu->prompt->visible.expr);
 658
 659         if (visible != no)
 660                 return true;
 661
 662         if (!sym || sym_get_tristate_value(menu->sym) == no)
 663                 return false;
 664
 665         for (child = menu->list; child; child = child->next) {
 666                 if (menu_is_visible(child)) {
 667                         if (sym)
 668                                 sym->flags |= SYMBOL_DEF_USER;
 669                         return true;
 670                 }
 671         }
 672
 673         return false;
 674 }
 675
 676 const char *menu_get_prompt(struct menu *menu)
 677 {
 678         if (menu->prompt)
 679                 return menu->prompt->text;
 680         else if (menu->sym)
 681                 return menu->sym->name;
 682         return NULL;
 683 }
 684
 685 struct menu *menu_get_root_menu(struct menu *menu)
 686 {
 687         return &rootmenu;
 688 }
 689
 690 struct menu *menu_get_parent_menu(struct menu *menu)
 691 {
 692         enum prop_type type;
 693
 694         for (; menu != &rootmenu; menu = menu->parent) {
 695                 type = menu->prompt ? menu->prompt->type : 0;
 696                 if (type == P_MENU)
 697                         break;
 698         }
 699         return menu;
 700 }
 701
 702 bool menu_has_help(struct menu *menu)
 703 {
 704         return menu->help != NULL;
 705 }
 706
 707 const char *menu_get_help(struct menu *menu)
 708 {
 709         if (menu->help)
 710                 return menu->help;
 711         else
 712                 return "";
 713 }
 714
 715 static void get_def_str(struct gstr *r, struct menu *menu)
 716 {
 717         str_printf(r, "Defined at %s:%d\n",
 718                    menu->file->name, menu->lineno);
 719 }
 720
 721 static void get_dep_str(struct gstr *r, struct expr *expr, const char *prefix)
 722 {
 723         if (!expr_is_yes(expr)) {
 724                 str_append(r, prefix);
 725                 expr_gstr_print(expr, r);
 726                 str_append(r, "\n");
 727         }
 728 }
 729
 730 static void get_prompt_str(struct gstr *r, struct property *prop,
 731                            struct list_head *head)
 732 {
 733         int i, j;
 734         struct menu *submenu[8], *menu, *location = NULL;
 735         struct jump_key *jump = NULL;
 736
 737         str_printf(r, "  Prompt: %s\n", prop->text);
 738
 739         get_dep_str(r, prop->menu->dep, "  Depends on: ");
 740         /*
 741          * Most prompts in Linux have visibility that exactly matches their
 742          * dependencies. For these, we print only the dependencies to improve
 743          * readability. However, prompts with inline "if" expressions and
 744          * prompts with a parent that has a "visible if" expression have
 745          * differing dependencies and visibility. In these rare cases, we
 746          * print both.
 747          */
 748         if (!expr_eq(prop->menu->dep, prop->visible.expr))
 749                 get_dep_str(r, prop->visible.expr, "  Visible if: ");
 750
 751         menu = prop->menu->parent;
 752         for (i = 0; menu != &rootmenu && i < 8; menu = menu->parent) {
 753                 bool accessible = menu_is_visible(menu);
 754
 755                 submenu[i++] = menu;
 756                 if (location == NULL && accessible)
 757                         location = menu;
 758         }
 759         if (head && location) {
 760                 jump = xmalloc(sizeof(struct jump_key));
 761
 762                 if (menu_is_visible(prop->menu)) {
 763                         /*
 764                          * There is not enough room to put the hint at the
 765                          * beginning of the "Prompt" line. Put the hint on the
 766                          * last "Location" line even when it would belong on
 767                          * the former.
 768                          */
 769                         jump->target = prop->menu;
 770                 } else
 771                         jump->target = location;
 772
 773                 if (list_empty(head))
 774                         jump->index = 0;
 775                 else
 776                         jump->index = list_entry(head->prev, struct jump_key,
 777                                                  entries)->index + 1;
 778
 779                 list_add_tail(&jump->entries, head);
 780         }
 781
 782         if (i > 0) {
 783                 str_printf(r, "  Location:\n");
 784                 for (j = 4; --i >= 0; j += 2) {
 785                         menu = submenu[i];
 786                         if (jump && menu == location)
 787                                 jump->offset = strlen(r->s);
 788                         str_printf(r, "%*c-> %s", j, ' ',
 789                                    menu_get_prompt(menu));
 790                         if (menu->sym) {
 791                                 str_printf(r, " (%s [=%s])", menu->sym->name ?
 792                                         menu->sym->name : "<choice>",
 793                                         sym_get_string_value(menu->sym));
 794                         }
 795                         str_append(r, "\n");
 796                 }
 797         }
 798 }
 799
 800 static void get_symbol_props_str(struct gstr *r, struct symbol *sym,
 801                                  enum prop_type tok, const char *prefix)
 802 {
 803         bool hit = false;
 804         struct property *prop;
 805
 806         for_all_properties(sym, prop, tok) {
 807                 if (!hit) {
 808                         str_append(r, prefix);
 809                         hit = true;
 810                 } else
 811                         str_printf(r, " && ");
 812                 expr_gstr_print(prop->expr, r);
 813         }
 814         if (hit)
 815                 str_append(r, "\n");
 816 }
 817
 818 /*
 819  * head is optional and may be NULL
 820  */
 821 static void get_symbol_str(struct gstr *r, struct symbol *sym,
 822                     struct list_head *head)
 823 {
 824         struct property *prop;
 825
 826         if (sym && sym->name) {
 827                 str_printf(r, "Symbol: %s [=%s]\n", sym->name,
 828                            sym_get_string_value(sym));
 829                 str_printf(r, "Type  : %s\n", sym_type_name(sym->type));
 830                 if (sym->type == S_INT || sym->type == S_HEX) {
 831                         prop = sym_get_range_prop(sym);
 832                         if (prop) {
 833                                 str_printf(r, "Range : ");
 834                                 expr_gstr_print(prop->expr, r);
 835                                 str_append(r, "\n");
 836                         }
 837                 }
 838         }
 839
 840         /* Print the definitions with prompts before the ones without */
 841         for_all_properties(sym, prop, P_SYMBOL) {
 842                 if (prop->menu->prompt) {
 843                         get_def_str(r, prop->menu);
 844                         get_prompt_str(r, prop->menu->prompt, head);
 845                 }
 846         }
 847
 848         for_all_properties(sym, prop, P_SYMBOL) {
 849                 if (!prop->menu->prompt) {
 850                         get_def_str(r, prop->menu);
 851                         get_dep_str(r, prop->menu->dep, "  Depends on: ");
 852                 }
 853         }
 854
 855         get_symbol_props_str(r, sym, P_SELECT, "Selects: ");
 856         if (sym->rev_dep.expr) {
 857                 expr_gstr_print_revdep(sym->rev_dep.expr, r, yes, "Selected by [y]:\n");
 858                 expr_gstr_print_revdep(sym->rev_dep.expr, r, mod, "Selected by [m]:\n");
 859                 expr_gstr_print_revdep(sym->rev_dep.expr, r, no, "Selected by [n]:\n");
 860         }
 861
 862         get_symbol_props_str(r, sym, P_IMPLY, "Implies: ");
 863         if (sym->implied.expr) {
 864                 expr_gstr_print_revdep(sym->implied.expr, r, yes, "Implied by [y]:\n");
 865                 expr_gstr_print_revdep(sym->implied.expr, r, mod, "Implied by [m]:\n");
 866                 expr_gstr_print_revdep(sym->implied.expr, r, no, "Implied by [n]:\n");
 867         }
 868
 869         str_append(r, "\n\n");
 870 }
 871
 872 struct gstr get_relations_str(struct symbol **sym_arr, struct list_head *head)
 873 {
 874         struct symbol *sym;
 875         struct gstr res = str_new();
 876         int i;
 877
 878         for (i = 0; sym_arr && (sym = sym_arr[i]); i++)
 879                 get_symbol_str(&res, sym, head);
 880         if (!i)
 881                 str_append(&res, "No matches found.\n");
 882         return res;
 883 }
 884
 885
 886 void menu_get_ext_help(struct menu *menu, struct gstr *help)
 887 {
 888         struct symbol *sym = menu->sym;
 889         const char *help_text = nohelp_text;
 890
 891         if (menu_has_help(menu)) {
 892                 if (sym->name)
 893                         str_printf(help, "%s%s:\n\n", CONFIG_, sym->name);
 894                 help_text = menu_get_help(menu);
 895         }
 896         str_printf(help, "%s\n", help_text);
 897         if (sym)
 898                 get_symbol_str(help, sym, NULL);
 899 }