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v5.9
   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 <stdlib.h>
   8#include <string.h>
   9#include <regex.h>
  10#include <sys/utsname.h>
  11
  12#include "lkc.h"
  13
  14struct symbol symbol_yes = {
  15	.name = "y",
  16	.curr = { "y", yes },
  17	.flags = SYMBOL_CONST|SYMBOL_VALID,
  18};
  19
  20struct symbol symbol_mod = {
  21	.name = "m",
  22	.curr = { "m", mod },
  23	.flags = SYMBOL_CONST|SYMBOL_VALID,
  24};
  25
  26struct symbol symbol_no = {
  27	.name = "n",
  28	.curr = { "n", no },
  29	.flags = SYMBOL_CONST|SYMBOL_VALID,
  30};
  31
  32static struct symbol symbol_empty = {
  33	.name = "",
  34	.curr = { "", no },
  35	.flags = SYMBOL_VALID,
  36};
  37
  38struct symbol *sym_defconfig_list;
  39struct symbol *modules_sym;
  40static tristate modules_val;
  41
  42enum symbol_type sym_get_type(struct symbol *sym)
  43{
  44	enum symbol_type type = sym->type;
  45
  46	if (type == S_TRISTATE) {
  47		if (sym_is_choice_value(sym) && sym->visible == yes)
  48			type = S_BOOLEAN;
  49		else if (modules_val == no)
  50			type = S_BOOLEAN;
  51	}
  52	return type;
  53}
  54
  55const char *sym_type_name(enum symbol_type type)
  56{
  57	switch (type) {
  58	case S_BOOLEAN:
  59		return "bool";
  60	case S_TRISTATE:
  61		return "tristate";
  62	case S_INT:
  63		return "integer";
  64	case S_HEX:
  65		return "hex";
  66	case S_STRING:
  67		return "string";
  68	case S_UNKNOWN:
  69		return "unknown";
  70	}
  71	return "???";
  72}
  73
  74struct property *sym_get_choice_prop(struct symbol *sym)
  75{
  76	struct property *prop;
  77
  78	for_all_choices(sym, prop)
  79		return prop;
  80	return NULL;
  81}
  82
  83static struct property *sym_get_default_prop(struct symbol *sym)
  84{
  85	struct property *prop;
  86
  87	for_all_defaults(sym, prop) {
  88		prop->visible.tri = expr_calc_value(prop->visible.expr);
  89		if (prop->visible.tri != no)
  90			return prop;
  91	}
  92	return NULL;
  93}
  94
  95struct property *sym_get_range_prop(struct symbol *sym)
  96{
  97	struct property *prop;
  98
  99	for_all_properties(sym, prop, P_RANGE) {
 100		prop->visible.tri = expr_calc_value(prop->visible.expr);
 101		if (prop->visible.tri != no)
 102			return prop;
 103	}
 104	return NULL;
 105}
 106
 107static long long sym_get_range_val(struct symbol *sym, int base)
 108{
 109	sym_calc_value(sym);
 110	switch (sym->type) {
 111	case S_INT:
 112		base = 10;
 113		break;
 114	case S_HEX:
 115		base = 16;
 116		break;
 117	default:
 118		break;
 119	}
 120	return strtoll(sym->curr.val, NULL, base);
 121}
 122
 123static void sym_validate_range(struct symbol *sym)
 124{
 125	struct property *prop;
 126	int base;
 127	long long val, val2;
 128	char str[64];
 129
 130	switch (sym->type) {
 131	case S_INT:
 132		base = 10;
 133		break;
 134	case S_HEX:
 135		base = 16;
 136		break;
 137	default:
 138		return;
 139	}
 140	prop = sym_get_range_prop(sym);
 141	if (!prop)
 142		return;
 143	val = strtoll(sym->curr.val, NULL, base);
 144	val2 = sym_get_range_val(prop->expr->left.sym, base);
 145	if (val >= val2) {
 146		val2 = sym_get_range_val(prop->expr->right.sym, base);
 147		if (val <= val2)
 148			return;
 149	}
 150	if (sym->type == S_INT)
 151		sprintf(str, "%lld", val2);
 152	else
 153		sprintf(str, "0x%llx", val2);
 154	sym->curr.val = xstrdup(str);
 155}
 156
 157static void sym_set_changed(struct symbol *sym)
 158{
 159	struct property *prop;
 160
 161	sym->flags |= SYMBOL_CHANGED;
 162	for (prop = sym->prop; prop; prop = prop->next) {
 163		if (prop->menu)
 164			prop->menu->flags |= MENU_CHANGED;
 165	}
 166}
 167
 168static void sym_set_all_changed(void)
 169{
 170	struct symbol *sym;
 171	int i;
 172
 173	for_all_symbols(i, sym)
 174		sym_set_changed(sym);
 175}
 176
 177static void sym_calc_visibility(struct symbol *sym)
 178{
 179	struct property *prop;
 180	struct symbol *choice_sym = NULL;
 181	tristate tri;
 182
 183	/* any prompt visible? */
 184	tri = no;
 185
 186	if (sym_is_choice_value(sym))
 187		choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 188
 189	for_all_prompts(sym, prop) {
 190		prop->visible.tri = expr_calc_value(prop->visible.expr);
 191		/*
 192		 * Tristate choice_values with visibility 'mod' are
 193		 * not visible if the corresponding choice's value is
 194		 * 'yes'.
 195		 */
 196		if (choice_sym && sym->type == S_TRISTATE &&
 197		    prop->visible.tri == mod && choice_sym->curr.tri == yes)
 198			prop->visible.tri = no;
 199
 200		tri = EXPR_OR(tri, prop->visible.tri);
 201	}
 202	if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 203		tri = yes;
 204	if (sym->visible != tri) {
 205		sym->visible = tri;
 206		sym_set_changed(sym);
 207	}
 208	if (sym_is_choice_value(sym))
 209		return;
 210	/* defaulting to "yes" if no explicit "depends on" are given */
 211	tri = yes;
 212	if (sym->dir_dep.expr)
 213		tri = expr_calc_value(sym->dir_dep.expr);
 214	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 215		tri = yes;
 216	if (sym->dir_dep.tri != tri) {
 217		sym->dir_dep.tri = tri;
 218		sym_set_changed(sym);
 219	}
 220	tri = no;
 221	if (sym->rev_dep.expr)
 222		tri = expr_calc_value(sym->rev_dep.expr);
 223	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 224		tri = yes;
 225	if (sym->rev_dep.tri != tri) {
 226		sym->rev_dep.tri = tri;
 227		sym_set_changed(sym);
 228	}
 229	tri = no;
 230	if (sym->implied.expr)
 231		tri = expr_calc_value(sym->implied.expr);
 232	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 233		tri = yes;
 234	if (sym->implied.tri != tri) {
 235		sym->implied.tri = tri;
 236		sym_set_changed(sym);
 237	}
 238}
 239
 240/*
 241 * Find the default symbol for a choice.
 242 * First try the default values for the choice symbol
 243 * Next locate the first visible choice value
 244 * Return NULL if none was found
 245 */
 246struct symbol *sym_choice_default(struct symbol *sym)
 247{
 248	struct symbol *def_sym;
 249	struct property *prop;
 250	struct expr *e;
 251
 252	/* any of the defaults visible? */
 253	for_all_defaults(sym, prop) {
 254		prop->visible.tri = expr_calc_value(prop->visible.expr);
 255		if (prop->visible.tri == no)
 256			continue;
 257		def_sym = prop_get_symbol(prop);
 258		if (def_sym->visible != no)
 259			return def_sym;
 260	}
 261
 262	/* just get the first visible value */
 263	prop = sym_get_choice_prop(sym);
 264	expr_list_for_each_sym(prop->expr, e, def_sym)
 265		if (def_sym->visible != no)
 266			return def_sym;
 267
 268	/* failed to locate any defaults */
 269	return NULL;
 270}
 271
 272static struct symbol *sym_calc_choice(struct symbol *sym)
 273{
 274	struct symbol *def_sym;
 275	struct property *prop;
 276	struct expr *e;
 277	int flags;
 278
 279	/* first calculate all choice values' visibilities */
 280	flags = sym->flags;
 281	prop = sym_get_choice_prop(sym);
 282	expr_list_for_each_sym(prop->expr, e, def_sym) {
 283		sym_calc_visibility(def_sym);
 284		if (def_sym->visible != no)
 285			flags &= def_sym->flags;
 286	}
 287
 288	sym->flags &= flags | ~SYMBOL_DEF_USER;
 289
 290	/* is the user choice visible? */
 291	def_sym = sym->def[S_DEF_USER].val;
 292	if (def_sym && def_sym->visible != no)
 293		return def_sym;
 294
 295	def_sym = sym_choice_default(sym);
 296
 297	if (def_sym == NULL)
 298		/* no choice? reset tristate value */
 299		sym->curr.tri = no;
 300
 301	return def_sym;
 302}
 303
 304static void sym_warn_unmet_dep(struct symbol *sym)
 305{
 306	struct gstr gs = str_new();
 307
 308	str_printf(&gs,
 309		   "\nWARNING: unmet direct dependencies detected for %s\n",
 310		   sym->name);
 311	str_printf(&gs,
 312		   "  Depends on [%c]: ",
 313		   sym->dir_dep.tri == mod ? 'm' : 'n');
 314	expr_gstr_print(sym->dir_dep.expr, &gs);
 315	str_printf(&gs, "\n");
 316
 317	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 318			       "  Selected by [y]:\n");
 319	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 320			       "  Selected by [m]:\n");
 321
 322	fputs(str_get(&gs), stderr);
 323}
 324
 325void sym_calc_value(struct symbol *sym)
 326{
 327	struct symbol_value newval, oldval;
 328	struct property *prop;
 329	struct expr *e;
 330
 331	if (!sym)
 332		return;
 333
 334	if (sym->flags & SYMBOL_VALID)
 335		return;
 336
 337	if (sym_is_choice_value(sym) &&
 338	    sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 339		sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 340		prop = sym_get_choice_prop(sym);
 341		sym_calc_value(prop_get_symbol(prop));
 342	}
 343
 344	sym->flags |= SYMBOL_VALID;
 345
 346	oldval = sym->curr;
 347
 348	switch (sym->type) {
 349	case S_INT:
 350	case S_HEX:
 351	case S_STRING:
 352		newval = symbol_empty.curr;
 353		break;
 354	case S_BOOLEAN:
 355	case S_TRISTATE:
 356		newval = symbol_no.curr;
 357		break;
 358	default:
 359		sym->curr.val = sym->name;
 360		sym->curr.tri = no;
 361		return;
 362	}
 363	sym->flags &= ~SYMBOL_WRITE;
 364
 365	sym_calc_visibility(sym);
 366
 367	if (sym->visible != no)
 368		sym->flags |= SYMBOL_WRITE;
 369
 370	/* set default if recursively called */
 371	sym->curr = newval;
 372
 373	switch (sym_get_type(sym)) {
 374	case S_BOOLEAN:
 375	case S_TRISTATE:
 376		if (sym_is_choice_value(sym) && sym->visible == yes) {
 377			prop = sym_get_choice_prop(sym);
 378			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 379		} else {
 380			if (sym->visible != no) {
 381				/* if the symbol is visible use the user value
 382				 * if available, otherwise try the default value
 383				 */
 384				if (sym_has_value(sym)) {
 385					newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 386							      sym->visible);
 387					goto calc_newval;
 388				}
 389			}
 390			if (sym->rev_dep.tri != no)
 391				sym->flags |= SYMBOL_WRITE;
 392			if (!sym_is_choice(sym)) {
 393				prop = sym_get_default_prop(sym);
 394				if (prop) {
 395					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 396							      prop->visible.tri);
 397					if (newval.tri != no)
 398						sym->flags |= SYMBOL_WRITE;
 399				}
 400				if (sym->implied.tri != no) {
 401					sym->flags |= SYMBOL_WRITE;
 402					newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 403					newval.tri = EXPR_AND(newval.tri,
 404							      sym->dir_dep.tri);
 405				}
 406			}
 407		calc_newval:
 408			if (sym->dir_dep.tri < sym->rev_dep.tri)
 409				sym_warn_unmet_dep(sym);
 410			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 411		}
 412		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
 
 413			newval.tri = yes;
 414		break;
 415	case S_STRING:
 416	case S_HEX:
 417	case S_INT:
 418		if (sym->visible != no && sym_has_value(sym)) {
 419			newval.val = sym->def[S_DEF_USER].val;
 420			break;
 421		}
 422		prop = sym_get_default_prop(sym);
 423		if (prop) {
 424			struct symbol *ds = prop_get_symbol(prop);
 425			if (ds) {
 426				sym->flags |= SYMBOL_WRITE;
 427				sym_calc_value(ds);
 428				newval.val = ds->curr.val;
 429			}
 430		}
 431		break;
 432	default:
 433		;
 434	}
 435
 436	sym->curr = newval;
 437	if (sym_is_choice(sym) && newval.tri == yes)
 438		sym->curr.val = sym_calc_choice(sym);
 439	sym_validate_range(sym);
 440
 441	if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
 442		sym_set_changed(sym);
 443		if (modules_sym == sym) {
 444			sym_set_all_changed();
 445			modules_val = modules_sym->curr.tri;
 446		}
 447	}
 448
 449	if (sym_is_choice(sym)) {
 450		struct symbol *choice_sym;
 451
 452		prop = sym_get_choice_prop(sym);
 453		expr_list_for_each_sym(prop->expr, e, choice_sym) {
 454			if ((sym->flags & SYMBOL_WRITE) &&
 455			    choice_sym->visible != no)
 456				choice_sym->flags |= SYMBOL_WRITE;
 457			if (sym->flags & SYMBOL_CHANGED)
 458				sym_set_changed(choice_sym);
 459		}
 460	}
 461
 462	if (sym->flags & SYMBOL_NO_WRITE)
 463		sym->flags &= ~SYMBOL_WRITE;
 464
 465	if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 466		set_all_choice_values(sym);
 467}
 468
 469void sym_clear_all_valid(void)
 470{
 471	struct symbol *sym;
 472	int i;
 473
 474	for_all_symbols(i, sym)
 475		sym->flags &= ~SYMBOL_VALID;
 476	sym_add_change_count(1);
 477	sym_calc_value(modules_sym);
 478}
 479
 480bool sym_tristate_within_range(struct symbol *sym, tristate val)
 481{
 482	int type = sym_get_type(sym);
 483
 484	if (sym->visible == no)
 485		return false;
 486
 487	if (type != S_BOOLEAN && type != S_TRISTATE)
 488		return false;
 489
 490	if (type == S_BOOLEAN && val == mod)
 491		return false;
 492	if (sym->visible <= sym->rev_dep.tri)
 493		return false;
 
 
 494	if (sym_is_choice_value(sym) && sym->visible == yes)
 495		return val == yes;
 496	return val >= sym->rev_dep.tri && val <= sym->visible;
 497}
 498
 499bool sym_set_tristate_value(struct symbol *sym, tristate val)
 500{
 501	tristate oldval = sym_get_tristate_value(sym);
 502
 503	if (oldval != val && !sym_tristate_within_range(sym, val))
 504		return false;
 505
 506	if (!(sym->flags & SYMBOL_DEF_USER)) {
 507		sym->flags |= SYMBOL_DEF_USER;
 508		sym_set_changed(sym);
 509	}
 510	/*
 511	 * setting a choice value also resets the new flag of the choice
 512	 * symbol and all other choice values.
 513	 */
 514	if (sym_is_choice_value(sym) && val == yes) {
 515		struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 516		struct property *prop;
 517		struct expr *e;
 518
 519		cs->def[S_DEF_USER].val = sym;
 520		cs->flags |= SYMBOL_DEF_USER;
 521		prop = sym_get_choice_prop(cs);
 522		for (e = prop->expr; e; e = e->left.expr) {
 523			if (e->right.sym->visible != no)
 524				e->right.sym->flags |= SYMBOL_DEF_USER;
 525		}
 526	}
 527
 528	sym->def[S_DEF_USER].tri = val;
 529	if (oldval != val)
 530		sym_clear_all_valid();
 531
 532	return true;
 533}
 534
 535tristate sym_toggle_tristate_value(struct symbol *sym)
 536{
 537	tristate oldval, newval;
 538
 539	oldval = newval = sym_get_tristate_value(sym);
 540	do {
 541		switch (newval) {
 542		case no:
 543			newval = mod;
 544			break;
 545		case mod:
 546			newval = yes;
 547			break;
 548		case yes:
 549			newval = no;
 550			break;
 551		}
 552		if (sym_set_tristate_value(sym, newval))
 553			break;
 554	} while (oldval != newval);
 555	return newval;
 556}
 557
 558bool sym_string_valid(struct symbol *sym, const char *str)
 559{
 560	signed char ch;
 561
 562	switch (sym->type) {
 563	case S_STRING:
 564		return true;
 565	case S_INT:
 566		ch = *str++;
 567		if (ch == '-')
 568			ch = *str++;
 569		if (!isdigit(ch))
 570			return false;
 571		if (ch == '0' && *str != 0)
 572			return false;
 573		while ((ch = *str++)) {
 574			if (!isdigit(ch))
 575				return false;
 576		}
 577		return true;
 578	case S_HEX:
 579		if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 580			str += 2;
 581		ch = *str++;
 582		do {
 583			if (!isxdigit(ch))
 584				return false;
 585		} while ((ch = *str++));
 586		return true;
 587	case S_BOOLEAN:
 588	case S_TRISTATE:
 589		switch (str[0]) {
 590		case 'y': case 'Y':
 591		case 'm': case 'M':
 592		case 'n': case 'N':
 593			return true;
 594		}
 595		return false;
 596	default:
 597		return false;
 598	}
 599}
 600
 601bool sym_string_within_range(struct symbol *sym, const char *str)
 602{
 603	struct property *prop;
 604	long long val;
 605
 606	switch (sym->type) {
 607	case S_STRING:
 608		return sym_string_valid(sym, str);
 609	case S_INT:
 610		if (!sym_string_valid(sym, str))
 611			return false;
 612		prop = sym_get_range_prop(sym);
 613		if (!prop)
 614			return true;
 615		val = strtoll(str, NULL, 10);
 616		return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 617		       val <= sym_get_range_val(prop->expr->right.sym, 10);
 618	case S_HEX:
 619		if (!sym_string_valid(sym, str))
 620			return false;
 621		prop = sym_get_range_prop(sym);
 622		if (!prop)
 623			return true;
 624		val = strtoll(str, NULL, 16);
 625		return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 626		       val <= sym_get_range_val(prop->expr->right.sym, 16);
 627	case S_BOOLEAN:
 628	case S_TRISTATE:
 629		switch (str[0]) {
 630		case 'y': case 'Y':
 631			return sym_tristate_within_range(sym, yes);
 632		case 'm': case 'M':
 633			return sym_tristate_within_range(sym, mod);
 634		case 'n': case 'N':
 635			return sym_tristate_within_range(sym, no);
 636		}
 637		return false;
 638	default:
 639		return false;
 640	}
 641}
 642
 643bool sym_set_string_value(struct symbol *sym, const char *newval)
 644{
 645	const char *oldval;
 646	char *val;
 647	int size;
 648
 649	switch (sym->type) {
 650	case S_BOOLEAN:
 651	case S_TRISTATE:
 652		switch (newval[0]) {
 653		case 'y': case 'Y':
 654			return sym_set_tristate_value(sym, yes);
 655		case 'm': case 'M':
 656			return sym_set_tristate_value(sym, mod);
 657		case 'n': case 'N':
 658			return sym_set_tristate_value(sym, no);
 659		}
 660		return false;
 661	default:
 662		;
 663	}
 664
 665	if (!sym_string_within_range(sym, newval))
 666		return false;
 667
 668	if (!(sym->flags & SYMBOL_DEF_USER)) {
 669		sym->flags |= SYMBOL_DEF_USER;
 670		sym_set_changed(sym);
 671	}
 672
 673	oldval = sym->def[S_DEF_USER].val;
 674	size = strlen(newval) + 1;
 675	if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 676		size += 2;
 677		sym->def[S_DEF_USER].val = val = xmalloc(size);
 678		*val++ = '0';
 679		*val++ = 'x';
 680	} else if (!oldval || strcmp(oldval, newval))
 681		sym->def[S_DEF_USER].val = val = xmalloc(size);
 682	else
 683		return true;
 684
 685	strcpy(val, newval);
 686	free((void *)oldval);
 687	sym_clear_all_valid();
 688
 689	return true;
 690}
 691
 692/*
 693 * Find the default value associated to a symbol.
 694 * For tristate symbol handle the modules=n case
 695 * in which case "m" becomes "y".
 696 * If the symbol does not have any default then fallback
 697 * to the fixed default values.
 698 */
 699const char *sym_get_string_default(struct symbol *sym)
 700{
 701	struct property *prop;
 702	struct symbol *ds;
 703	const char *str;
 704	tristate val;
 705
 706	sym_calc_visibility(sym);
 707	sym_calc_value(modules_sym);
 708	val = symbol_no.curr.tri;
 709	str = symbol_empty.curr.val;
 710
 711	/* If symbol has a default value look it up */
 712	prop = sym_get_default_prop(sym);
 713	if (prop != NULL) {
 714		switch (sym->type) {
 715		case S_BOOLEAN:
 716		case S_TRISTATE:
 717			/* The visibility may limit the value from yes => mod */
 718			val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 719			break;
 720		default:
 721			/*
 722			 * The following fails to handle the situation
 723			 * where a default value is further limited by
 724			 * the valid range.
 725			 */
 726			ds = prop_get_symbol(prop);
 727			if (ds != NULL) {
 728				sym_calc_value(ds);
 729				str = (const char *)ds->curr.val;
 730			}
 731		}
 732	}
 733
 734	/* Handle select statements */
 735	val = EXPR_OR(val, sym->rev_dep.tri);
 736
 737	/* transpose mod to yes if modules are not enabled */
 738	if (val == mod)
 739		if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 740			val = yes;
 741
 742	/* transpose mod to yes if type is bool */
 743	if (sym->type == S_BOOLEAN && val == mod)
 744		val = yes;
 745
 746	/* adjust the default value if this symbol is implied by another */
 747	if (val < sym->implied.tri)
 748		val = sym->implied.tri;
 749
 750	switch (sym->type) {
 751	case S_BOOLEAN:
 752	case S_TRISTATE:
 753		switch (val) {
 754		case no: return "n";
 755		case mod: return "m";
 756		case yes: return "y";
 757		}
 758	case S_INT:
 759	case S_HEX:
 760		return str;
 761	case S_STRING:
 762		return str;
 763	case S_UNKNOWN:
 764		break;
 765	}
 766	return "";
 767}
 768
 769const char *sym_get_string_value(struct symbol *sym)
 770{
 771	tristate val;
 772
 773	switch (sym->type) {
 774	case S_BOOLEAN:
 775	case S_TRISTATE:
 776		val = sym_get_tristate_value(sym);
 777		switch (val) {
 778		case no:
 779			return "n";
 780		case mod:
 781			sym_calc_value(modules_sym);
 782			return (modules_sym->curr.tri == no) ? "n" : "m";
 783		case yes:
 784			return "y";
 785		}
 786		break;
 787	default:
 788		;
 789	}
 790	return (const char *)sym->curr.val;
 791}
 792
 793bool sym_is_changeable(struct symbol *sym)
 794{
 795	return sym->visible > sym->rev_dep.tri;
 796}
 797
 798static unsigned strhash(const char *s)
 799{
 800	/* fnv32 hash */
 801	unsigned hash = 2166136261U;
 802	for (; *s; s++)
 803		hash = (hash ^ *s) * 0x01000193;
 804	return hash;
 805}
 806
 807struct symbol *sym_lookup(const char *name, int flags)
 808{
 809	struct symbol *symbol;
 810	char *new_name;
 811	int hash;
 812
 813	if (name) {
 814		if (name[0] && !name[1]) {
 815			switch (name[0]) {
 816			case 'y': return &symbol_yes;
 817			case 'm': return &symbol_mod;
 818			case 'n': return &symbol_no;
 819			}
 820		}
 821		hash = strhash(name) % SYMBOL_HASHSIZE;
 822
 823		for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 824			if (symbol->name &&
 825			    !strcmp(symbol->name, name) &&
 826			    (flags ? symbol->flags & flags
 827				   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 828				return symbol;
 829		}
 830		new_name = xstrdup(name);
 831	} else {
 832		new_name = NULL;
 833		hash = 0;
 834	}
 835
 836	symbol = xmalloc(sizeof(*symbol));
 837	memset(symbol, 0, sizeof(*symbol));
 838	symbol->name = new_name;
 839	symbol->type = S_UNKNOWN;
 840	symbol->flags = flags;
 841
 842	symbol->next = symbol_hash[hash];
 843	symbol_hash[hash] = symbol;
 844
 845	return symbol;
 846}
 847
 848struct symbol *sym_find(const char *name)
 849{
 850	struct symbol *symbol = NULL;
 851	int hash = 0;
 852
 853	if (!name)
 854		return NULL;
 855
 856	if (name[0] && !name[1]) {
 857		switch (name[0]) {
 858		case 'y': return &symbol_yes;
 859		case 'm': return &symbol_mod;
 860		case 'n': return &symbol_no;
 861		}
 862	}
 863	hash = strhash(name) % SYMBOL_HASHSIZE;
 864
 865	for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 866		if (symbol->name &&
 867		    !strcmp(symbol->name, name) &&
 868		    !(symbol->flags & SYMBOL_CONST))
 869				break;
 870	}
 871
 872	return symbol;
 873}
 874
 875const char *sym_escape_string_value(const char *in)
 876{
 877	const char *p;
 878	size_t reslen;
 879	char *res;
 880	size_t l;
 881
 882	reslen = strlen(in) + strlen("\"\"") + 1;
 883
 884	p = in;
 885	for (;;) {
 886		l = strcspn(p, "\"\\");
 887		p += l;
 888
 889		if (p[0] == '\0')
 890			break;
 891
 892		reslen++;
 893		p++;
 894	}
 895
 896	res = xmalloc(reslen);
 897	res[0] = '\0';
 898
 899	strcat(res, "\"");
 900
 901	p = in;
 902	for (;;) {
 903		l = strcspn(p, "\"\\");
 904		strncat(res, p, l);
 905		p += l;
 906
 907		if (p[0] == '\0')
 908			break;
 909
 910		strcat(res, "\\");
 911		strncat(res, p++, 1);
 912	}
 913
 914	strcat(res, "\"");
 915	return res;
 916}
 917
 918struct sym_match {
 919	struct symbol	*sym;
 920	off_t		so, eo;
 921};
 922
 923/* Compare matched symbols as thus:
 924 * - first, symbols that match exactly
 925 * - then, alphabetical sort
 926 */
 927static int sym_rel_comp(const void *sym1, const void *sym2)
 928{
 929	const struct sym_match *s1 = sym1;
 930	const struct sym_match *s2 = sym2;
 931	int exact1, exact2;
 932
 933	/* Exact match:
 934	 * - if matched length on symbol s1 is the length of that symbol,
 935	 *   then this symbol should come first;
 936	 * - if matched length on symbol s2 is the length of that symbol,
 937	 *   then this symbol should come first.
 938	 * Note: since the search can be a regexp, both symbols may match
 939	 * exactly; if this is the case, we can't decide which comes first,
 940	 * and we fallback to sorting alphabetically.
 941	 */
 942	exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 943	exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 944	if (exact1 && !exact2)
 945		return -1;
 946	if (!exact1 && exact2)
 947		return 1;
 948
 949	/* As a fallback, sort symbols alphabetically */
 950	return strcmp(s1->sym->name, s2->sym->name);
 951}
 952
 953struct symbol **sym_re_search(const char *pattern)
 954{
 955	struct symbol *sym, **sym_arr = NULL;
 956	struct sym_match *sym_match_arr = NULL;
 957	int i, cnt, size;
 958	regex_t re;
 959	regmatch_t match[1];
 960
 961	cnt = size = 0;
 962	/* Skip if empty */
 963	if (strlen(pattern) == 0)
 964		return NULL;
 965	if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 966		return NULL;
 967
 968	for_all_symbols(i, sym) {
 969		if (sym->flags & SYMBOL_CONST || !sym->name)
 970			continue;
 971		if (regexec(&re, sym->name, 1, match, 0))
 972			continue;
 973		if (cnt >= size) {
 974			void *tmp;
 975			size += 16;
 976			tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 977			if (!tmp)
 978				goto sym_re_search_free;
 979			sym_match_arr = tmp;
 980		}
 981		sym_calc_value(sym);
 982		/* As regexec returned 0, we know we have a match, so
 983		 * we can use match[0].rm_[se]o without further checks
 984		 */
 985		sym_match_arr[cnt].so = match[0].rm_so;
 986		sym_match_arr[cnt].eo = match[0].rm_eo;
 987		sym_match_arr[cnt++].sym = sym;
 988	}
 989	if (sym_match_arr) {
 990		qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 991		sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 992		if (!sym_arr)
 993			goto sym_re_search_free;
 994		for (i = 0; i < cnt; i++)
 995			sym_arr[i] = sym_match_arr[i].sym;
 996		sym_arr[cnt] = NULL;
 997	}
 998sym_re_search_free:
 999	/* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1000	free(sym_match_arr);
1001	regfree(&re);
1002
1003	return sym_arr;
1004}
1005
1006/*
1007 * When we check for recursive dependencies we use a stack to save
1008 * current state so we can print out relevant info to user.
1009 * The entries are located on the call stack so no need to free memory.
1010 * Note insert() remove() must always match to properly clear the stack.
1011 */
1012static struct dep_stack {
1013	struct dep_stack *prev, *next;
1014	struct symbol *sym;
1015	struct property *prop;
1016	struct expr **expr;
1017} *check_top;
1018
1019static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1020{
1021	memset(stack, 0, sizeof(*stack));
1022	if (check_top)
1023		check_top->next = stack;
1024	stack->prev = check_top;
1025	stack->sym = sym;
1026	check_top = stack;
1027}
1028
1029static void dep_stack_remove(void)
1030{
1031	check_top = check_top->prev;
1032	if (check_top)
1033		check_top->next = NULL;
1034}
1035
1036/*
1037 * Called when we have detected a recursive dependency.
1038 * check_top point to the top of the stact so we use
1039 * the ->prev pointer to locate the bottom of the stack.
1040 */
1041static void sym_check_print_recursive(struct symbol *last_sym)
1042{
1043	struct dep_stack *stack;
1044	struct symbol *sym, *next_sym;
1045	struct menu *menu = NULL;
1046	struct property *prop;
1047	struct dep_stack cv_stack;
1048
1049	if (sym_is_choice_value(last_sym)) {
1050		dep_stack_insert(&cv_stack, last_sym);
1051		last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1052	}
1053
1054	for (stack = check_top; stack != NULL; stack = stack->prev)
1055		if (stack->sym == last_sym)
1056			break;
1057	if (!stack) {
1058		fprintf(stderr, "unexpected recursive dependency error\n");
1059		return;
1060	}
1061
1062	for (; stack; stack = stack->next) {
1063		sym = stack->sym;
1064		next_sym = stack->next ? stack->next->sym : last_sym;
1065		prop = stack->prop;
1066		if (prop == NULL)
1067			prop = stack->sym->prop;
1068
1069		/* for choice values find the menu entry (used below) */
1070		if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1071			for (prop = sym->prop; prop; prop = prop->next) {
1072				menu = prop->menu;
1073				if (prop->menu)
1074					break;
1075			}
1076		}
1077		if (stack->sym == last_sym)
1078			fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1079				prop->file->name, prop->lineno);
1080
1081		if (sym_is_choice(sym)) {
1082			fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1083				menu->file->name, menu->lineno,
1084				sym->name ? sym->name : "<choice>",
1085				next_sym->name ? next_sym->name : "<choice>");
1086		} else if (sym_is_choice_value(sym)) {
1087			fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1088				menu->file->name, menu->lineno,
1089				sym->name ? sym->name : "<choice>",
1090				next_sym->name ? next_sym->name : "<choice>");
1091		} else if (stack->expr == &sym->dir_dep.expr) {
1092			fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1093				prop->file->name, prop->lineno,
1094				sym->name ? sym->name : "<choice>",
1095				next_sym->name ? next_sym->name : "<choice>");
1096		} else if (stack->expr == &sym->rev_dep.expr) {
1097			fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1098				prop->file->name, prop->lineno,
1099				sym->name ? sym->name : "<choice>",
1100				next_sym->name ? next_sym->name : "<choice>");
1101		} else if (stack->expr == &sym->implied.expr) {
1102			fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1103				prop->file->name, prop->lineno,
1104				sym->name ? sym->name : "<choice>",
1105				next_sym->name ? next_sym->name : "<choice>");
1106		} else if (stack->expr) {
1107			fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1108				prop->file->name, prop->lineno,
1109				sym->name ? sym->name : "<choice>",
1110				prop_get_type_name(prop->type),
1111				next_sym->name ? next_sym->name : "<choice>");
1112		} else {
1113			fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1114				prop->file->name, prop->lineno,
1115				sym->name ? sym->name : "<choice>",
1116				prop_get_type_name(prop->type),
1117				next_sym->name ? next_sym->name : "<choice>");
1118		}
1119	}
1120
1121	fprintf(stderr,
1122		"For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1123		"subsection \"Kconfig recursive dependency limitations\"\n"
1124		"\n");
1125
1126	if (check_top == &cv_stack)
1127		dep_stack_remove();
1128}
1129
1130static struct symbol *sym_check_expr_deps(struct expr *e)
1131{
1132	struct symbol *sym;
1133
1134	if (!e)
1135		return NULL;
1136	switch (e->type) {
1137	case E_OR:
1138	case E_AND:
1139		sym = sym_check_expr_deps(e->left.expr);
1140		if (sym)
1141			return sym;
1142		return sym_check_expr_deps(e->right.expr);
1143	case E_NOT:
1144		return sym_check_expr_deps(e->left.expr);
1145	case E_EQUAL:
1146	case E_GEQ:
1147	case E_GTH:
1148	case E_LEQ:
1149	case E_LTH:
1150	case E_UNEQUAL:
1151		sym = sym_check_deps(e->left.sym);
1152		if (sym)
1153			return sym;
1154		return sym_check_deps(e->right.sym);
1155	case E_SYMBOL:
1156		return sym_check_deps(e->left.sym);
1157	default:
1158		break;
1159	}
1160	fprintf(stderr, "Oops! How to check %d?\n", e->type);
1161	return NULL;
1162}
1163
1164/* return NULL when dependencies are OK */
1165static struct symbol *sym_check_sym_deps(struct symbol *sym)
1166{
1167	struct symbol *sym2;
1168	struct property *prop;
1169	struct dep_stack stack;
1170
1171	dep_stack_insert(&stack, sym);
1172
1173	stack.expr = &sym->dir_dep.expr;
1174	sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1175	if (sym2)
1176		goto out;
1177
1178	stack.expr = &sym->rev_dep.expr;
1179	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1180	if (sym2)
1181		goto out;
1182
1183	stack.expr = &sym->implied.expr;
1184	sym2 = sym_check_expr_deps(sym->implied.expr);
1185	if (sym2)
1186		goto out;
1187
1188	stack.expr = NULL;
1189
1190	for (prop = sym->prop; prop; prop = prop->next) {
1191		if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1192		    prop->type == P_IMPLY)
1193			continue;
1194		stack.prop = prop;
1195		sym2 = sym_check_expr_deps(prop->visible.expr);
1196		if (sym2)
1197			break;
1198		if (prop->type != P_DEFAULT || sym_is_choice(sym))
1199			continue;
1200		stack.expr = &prop->expr;
1201		sym2 = sym_check_expr_deps(prop->expr);
1202		if (sym2)
1203			break;
1204		stack.expr = NULL;
1205	}
1206
1207out:
1208	dep_stack_remove();
1209
1210	return sym2;
1211}
1212
1213static struct symbol *sym_check_choice_deps(struct symbol *choice)
1214{
1215	struct symbol *sym, *sym2;
1216	struct property *prop;
1217	struct expr *e;
1218	struct dep_stack stack;
1219
1220	dep_stack_insert(&stack, choice);
1221
1222	prop = sym_get_choice_prop(choice);
1223	expr_list_for_each_sym(prop->expr, e, sym)
1224		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1225
1226	choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1227	sym2 = sym_check_sym_deps(choice);
1228	choice->flags &= ~SYMBOL_CHECK;
1229	if (sym2)
1230		goto out;
1231
1232	expr_list_for_each_sym(prop->expr, e, sym) {
1233		sym2 = sym_check_sym_deps(sym);
1234		if (sym2)
1235			break;
1236	}
1237out:
1238	expr_list_for_each_sym(prop->expr, e, sym)
1239		sym->flags &= ~SYMBOL_CHECK;
1240
1241	if (sym2 && sym_is_choice_value(sym2) &&
1242	    prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1243		sym2 = choice;
1244
1245	dep_stack_remove();
1246
1247	return sym2;
1248}
1249
1250struct symbol *sym_check_deps(struct symbol *sym)
1251{
1252	struct symbol *sym2;
1253	struct property *prop;
1254
1255	if (sym->flags & SYMBOL_CHECK) {
1256		sym_check_print_recursive(sym);
1257		return sym;
1258	}
1259	if (sym->flags & SYMBOL_CHECKED)
1260		return NULL;
1261
1262	if (sym_is_choice_value(sym)) {
1263		struct dep_stack stack;
1264
1265		/* for choice groups start the check with main choice symbol */
1266		dep_stack_insert(&stack, sym);
1267		prop = sym_get_choice_prop(sym);
1268		sym2 = sym_check_deps(prop_get_symbol(prop));
1269		dep_stack_remove();
1270	} else if (sym_is_choice(sym)) {
1271		sym2 = sym_check_choice_deps(sym);
1272	} else {
1273		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1274		sym2 = sym_check_sym_deps(sym);
1275		sym->flags &= ~SYMBOL_CHECK;
1276	}
1277
1278	return sym2;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1279}
1280
1281struct symbol *prop_get_symbol(struct property *prop)
1282{
1283	if (prop->expr && (prop->expr->type == E_SYMBOL ||
1284			   prop->expr->type == E_LIST))
1285		return prop->expr->left.sym;
1286	return NULL;
1287}
1288
1289const char *prop_get_type_name(enum prop_type type)
1290{
1291	switch (type) {
1292	case P_PROMPT:
1293		return "prompt";
1294	case P_COMMENT:
1295		return "comment";
1296	case P_MENU:
1297		return "menu";
1298	case P_DEFAULT:
1299		return "default";
1300	case P_CHOICE:
1301		return "choice";
1302	case P_SELECT:
1303		return "select";
1304	case P_IMPLY:
1305		return "imply";
1306	case P_RANGE:
1307		return "range";
1308	case P_SYMBOL:
1309		return "symbol";
1310	case P_UNKNOWN:
1311		break;
1312	}
1313	return "unknown";
1314}
v5.4
   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 <stdlib.h>
   8#include <string.h>
   9#include <regex.h>
  10#include <sys/utsname.h>
  11
  12#include "lkc.h"
  13
  14struct symbol symbol_yes = {
  15	.name = "y",
  16	.curr = { "y", yes },
  17	.flags = SYMBOL_CONST|SYMBOL_VALID,
  18}, 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
  32struct symbol *sym_defconfig_list;
  33struct symbol *modules_sym;
  34tristate modules_val;
  35
  36enum symbol_type sym_get_type(struct symbol *sym)
  37{
  38	enum symbol_type type = sym->type;
  39
  40	if (type == S_TRISTATE) {
  41		if (sym_is_choice_value(sym) && sym->visible == yes)
  42			type = S_BOOLEAN;
  43		else if (modules_val == no)
  44			type = S_BOOLEAN;
  45	}
  46	return type;
  47}
  48
  49const char *sym_type_name(enum symbol_type type)
  50{
  51	switch (type) {
  52	case S_BOOLEAN:
  53		return "bool";
  54	case S_TRISTATE:
  55		return "tristate";
  56	case S_INT:
  57		return "integer";
  58	case S_HEX:
  59		return "hex";
  60	case S_STRING:
  61		return "string";
  62	case S_UNKNOWN:
  63		return "unknown";
  64	}
  65	return "???";
  66}
  67
  68struct property *sym_get_choice_prop(struct symbol *sym)
  69{
  70	struct property *prop;
  71
  72	for_all_choices(sym, prop)
  73		return prop;
  74	return NULL;
  75}
  76
  77static struct property *sym_get_default_prop(struct symbol *sym)
  78{
  79	struct property *prop;
  80
  81	for_all_defaults(sym, prop) {
  82		prop->visible.tri = expr_calc_value(prop->visible.expr);
  83		if (prop->visible.tri != no)
  84			return prop;
  85	}
  86	return NULL;
  87}
  88
  89struct property *sym_get_range_prop(struct symbol *sym)
  90{
  91	struct property *prop;
  92
  93	for_all_properties(sym, prop, P_RANGE) {
  94		prop->visible.tri = expr_calc_value(prop->visible.expr);
  95		if (prop->visible.tri != no)
  96			return prop;
  97	}
  98	return NULL;
  99}
 100
 101static long long sym_get_range_val(struct symbol *sym, int base)
 102{
 103	sym_calc_value(sym);
 104	switch (sym->type) {
 105	case S_INT:
 106		base = 10;
 107		break;
 108	case S_HEX:
 109		base = 16;
 110		break;
 111	default:
 112		break;
 113	}
 114	return strtoll(sym->curr.val, NULL, base);
 115}
 116
 117static void sym_validate_range(struct symbol *sym)
 118{
 119	struct property *prop;
 120	int base;
 121	long long val, val2;
 122	char str[64];
 123
 124	switch (sym->type) {
 125	case S_INT:
 126		base = 10;
 127		break;
 128	case S_HEX:
 129		base = 16;
 130		break;
 131	default:
 132		return;
 133	}
 134	prop = sym_get_range_prop(sym);
 135	if (!prop)
 136		return;
 137	val = strtoll(sym->curr.val, NULL, base);
 138	val2 = sym_get_range_val(prop->expr->left.sym, base);
 139	if (val >= val2) {
 140		val2 = sym_get_range_val(prop->expr->right.sym, base);
 141		if (val <= val2)
 142			return;
 143	}
 144	if (sym->type == S_INT)
 145		sprintf(str, "%lld", val2);
 146	else
 147		sprintf(str, "0x%llx", val2);
 148	sym->curr.val = xstrdup(str);
 149}
 150
 151static void sym_set_changed(struct symbol *sym)
 152{
 153	struct property *prop;
 154
 155	sym->flags |= SYMBOL_CHANGED;
 156	for (prop = sym->prop; prop; prop = prop->next) {
 157		if (prop->menu)
 158			prop->menu->flags |= MENU_CHANGED;
 159	}
 160}
 161
 162static void sym_set_all_changed(void)
 163{
 164	struct symbol *sym;
 165	int i;
 166
 167	for_all_symbols(i, sym)
 168		sym_set_changed(sym);
 169}
 170
 171static void sym_calc_visibility(struct symbol *sym)
 172{
 173	struct property *prop;
 174	struct symbol *choice_sym = NULL;
 175	tristate tri;
 176
 177	/* any prompt visible? */
 178	tri = no;
 179
 180	if (sym_is_choice_value(sym))
 181		choice_sym = prop_get_symbol(sym_get_choice_prop(sym));
 182
 183	for_all_prompts(sym, prop) {
 184		prop->visible.tri = expr_calc_value(prop->visible.expr);
 185		/*
 186		 * Tristate choice_values with visibility 'mod' are
 187		 * not visible if the corresponding choice's value is
 188		 * 'yes'.
 189		 */
 190		if (choice_sym && sym->type == S_TRISTATE &&
 191		    prop->visible.tri == mod && choice_sym->curr.tri == yes)
 192			prop->visible.tri = no;
 193
 194		tri = EXPR_OR(tri, prop->visible.tri);
 195	}
 196	if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
 197		tri = yes;
 198	if (sym->visible != tri) {
 199		sym->visible = tri;
 200		sym_set_changed(sym);
 201	}
 202	if (sym_is_choice_value(sym))
 203		return;
 204	/* defaulting to "yes" if no explicit "depends on" are given */
 205	tri = yes;
 206	if (sym->dir_dep.expr)
 207		tri = expr_calc_value(sym->dir_dep.expr);
 208	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 209		tri = yes;
 210	if (sym->dir_dep.tri != tri) {
 211		sym->dir_dep.tri = tri;
 212		sym_set_changed(sym);
 213	}
 214	tri = no;
 215	if (sym->rev_dep.expr)
 216		tri = expr_calc_value(sym->rev_dep.expr);
 217	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 218		tri = yes;
 219	if (sym->rev_dep.tri != tri) {
 220		sym->rev_dep.tri = tri;
 221		sym_set_changed(sym);
 222	}
 223	tri = no;
 224	if (sym->implied.expr && sym->dir_dep.tri != no)
 225		tri = expr_calc_value(sym->implied.expr);
 226	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 227		tri = yes;
 228	if (sym->implied.tri != tri) {
 229		sym->implied.tri = tri;
 230		sym_set_changed(sym);
 231	}
 232}
 233
 234/*
 235 * Find the default symbol for a choice.
 236 * First try the default values for the choice symbol
 237 * Next locate the first visible choice value
 238 * Return NULL if none was found
 239 */
 240struct symbol *sym_choice_default(struct symbol *sym)
 241{
 242	struct symbol *def_sym;
 243	struct property *prop;
 244	struct expr *e;
 245
 246	/* any of the defaults visible? */
 247	for_all_defaults(sym, prop) {
 248		prop->visible.tri = expr_calc_value(prop->visible.expr);
 249		if (prop->visible.tri == no)
 250			continue;
 251		def_sym = prop_get_symbol(prop);
 252		if (def_sym->visible != no)
 253			return def_sym;
 254	}
 255
 256	/* just get the first visible value */
 257	prop = sym_get_choice_prop(sym);
 258	expr_list_for_each_sym(prop->expr, e, def_sym)
 259		if (def_sym->visible != no)
 260			return def_sym;
 261
 262	/* failed to locate any defaults */
 263	return NULL;
 264}
 265
 266static struct symbol *sym_calc_choice(struct symbol *sym)
 267{
 268	struct symbol *def_sym;
 269	struct property *prop;
 270	struct expr *e;
 271	int flags;
 272
 273	/* first calculate all choice values' visibilities */
 274	flags = sym->flags;
 275	prop = sym_get_choice_prop(sym);
 276	expr_list_for_each_sym(prop->expr, e, def_sym) {
 277		sym_calc_visibility(def_sym);
 278		if (def_sym->visible != no)
 279			flags &= def_sym->flags;
 280	}
 281
 282	sym->flags &= flags | ~SYMBOL_DEF_USER;
 283
 284	/* is the user choice visible? */
 285	def_sym = sym->def[S_DEF_USER].val;
 286	if (def_sym && def_sym->visible != no)
 287		return def_sym;
 288
 289	def_sym = sym_choice_default(sym);
 290
 291	if (def_sym == NULL)
 292		/* no choice? reset tristate value */
 293		sym->curr.tri = no;
 294
 295	return def_sym;
 296}
 297
 298static void sym_warn_unmet_dep(struct symbol *sym)
 299{
 300	struct gstr gs = str_new();
 301
 302	str_printf(&gs,
 303		   "\nWARNING: unmet direct dependencies detected for %s\n",
 304		   sym->name);
 305	str_printf(&gs,
 306		   "  Depends on [%c]: ",
 307		   sym->dir_dep.tri == mod ? 'm' : 'n');
 308	expr_gstr_print(sym->dir_dep.expr, &gs);
 309	str_printf(&gs, "\n");
 310
 311	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
 312			       "  Selected by [y]:\n");
 313	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
 314			       "  Selected by [m]:\n");
 315
 316	fputs(str_get(&gs), stderr);
 317}
 318
 319void sym_calc_value(struct symbol *sym)
 320{
 321	struct symbol_value newval, oldval;
 322	struct property *prop;
 323	struct expr *e;
 324
 325	if (!sym)
 326		return;
 327
 328	if (sym->flags & SYMBOL_VALID)
 329		return;
 330
 331	if (sym_is_choice_value(sym) &&
 332	    sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
 333		sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
 334		prop = sym_get_choice_prop(sym);
 335		sym_calc_value(prop_get_symbol(prop));
 336	}
 337
 338	sym->flags |= SYMBOL_VALID;
 339
 340	oldval = sym->curr;
 341
 342	switch (sym->type) {
 343	case S_INT:
 344	case S_HEX:
 345	case S_STRING:
 346		newval = symbol_empty.curr;
 347		break;
 348	case S_BOOLEAN:
 349	case S_TRISTATE:
 350		newval = symbol_no.curr;
 351		break;
 352	default:
 353		sym->curr.val = sym->name;
 354		sym->curr.tri = no;
 355		return;
 356	}
 357	sym->flags &= ~SYMBOL_WRITE;
 358
 359	sym_calc_visibility(sym);
 360
 361	if (sym->visible != no)
 362		sym->flags |= SYMBOL_WRITE;
 363
 364	/* set default if recursively called */
 365	sym->curr = newval;
 366
 367	switch (sym_get_type(sym)) {
 368	case S_BOOLEAN:
 369	case S_TRISTATE:
 370		if (sym_is_choice_value(sym) && sym->visible == yes) {
 371			prop = sym_get_choice_prop(sym);
 372			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
 373		} else {
 374			if (sym->visible != no) {
 375				/* if the symbol is visible use the user value
 376				 * if available, otherwise try the default value
 377				 */
 378				if (sym_has_value(sym)) {
 379					newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
 380							      sym->visible);
 381					goto calc_newval;
 382				}
 383			}
 384			if (sym->rev_dep.tri != no)
 385				sym->flags |= SYMBOL_WRITE;
 386			if (!sym_is_choice(sym)) {
 387				prop = sym_get_default_prop(sym);
 388				if (prop) {
 389					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 390							      prop->visible.tri);
 391					if (newval.tri != no)
 392						sym->flags |= SYMBOL_WRITE;
 393				}
 394				if (sym->implied.tri != no) {
 395					sym->flags |= SYMBOL_WRITE;
 396					newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
 
 
 397				}
 398			}
 399		calc_newval:
 400			if (sym->dir_dep.tri < sym->rev_dep.tri)
 401				sym_warn_unmet_dep(sym);
 402			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 403		}
 404		if (newval.tri == mod &&
 405		    (sym_get_type(sym) == S_BOOLEAN || sym->implied.tri == yes))
 406			newval.tri = yes;
 407		break;
 408	case S_STRING:
 409	case S_HEX:
 410	case S_INT:
 411		if (sym->visible != no && sym_has_value(sym)) {
 412			newval.val = sym->def[S_DEF_USER].val;
 413			break;
 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_NO_WRITE)
 456		sym->flags &= ~SYMBOL_WRITE;
 457
 458	if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
 459		set_all_choice_values(sym);
 460}
 461
 462void 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	sym_calc_value(modules_sym);
 471}
 472
 473bool sym_tristate_within_range(struct symbol *sym, tristate val)
 474{
 475	int type = sym_get_type(sym);
 476
 477	if (sym->visible == no)
 478		return false;
 479
 480	if (type != S_BOOLEAN && type != S_TRISTATE)
 481		return false;
 482
 483	if (type == S_BOOLEAN && val == mod)
 484		return false;
 485	if (sym->visible <= sym->rev_dep.tri)
 486		return false;
 487	if (sym->implied.tri == yes && val == mod)
 488		return false;
 489	if (sym_is_choice_value(sym) && sym->visible == yes)
 490		return val == yes;
 491	return val >= sym->rev_dep.tri && val <= sym->visible;
 492}
 493
 494bool sym_set_tristate_value(struct symbol *sym, tristate val)
 495{
 496	tristate oldval = sym_get_tristate_value(sym);
 497
 498	if (oldval != val && !sym_tristate_within_range(sym, val))
 499		return false;
 500
 501	if (!(sym->flags & SYMBOL_DEF_USER)) {
 502		sym->flags |= SYMBOL_DEF_USER;
 503		sym_set_changed(sym);
 504	}
 505	/*
 506	 * setting a choice value also resets the new flag of the choice
 507	 * symbol and all other choice values.
 508	 */
 509	if (sym_is_choice_value(sym) && val == yes) {
 510		struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 511		struct property *prop;
 512		struct expr *e;
 513
 514		cs->def[S_DEF_USER].val = sym;
 515		cs->flags |= SYMBOL_DEF_USER;
 516		prop = sym_get_choice_prop(cs);
 517		for (e = prop->expr; e; e = e->left.expr) {
 518			if (e->right.sym->visible != no)
 519				e->right.sym->flags |= SYMBOL_DEF_USER;
 520		}
 521	}
 522
 523	sym->def[S_DEF_USER].tri = val;
 524	if (oldval != val)
 525		sym_clear_all_valid();
 526
 527	return true;
 528}
 529
 530tristate sym_toggle_tristate_value(struct symbol *sym)
 531{
 532	tristate oldval, newval;
 533
 534	oldval = newval = sym_get_tristate_value(sym);
 535	do {
 536		switch (newval) {
 537		case no:
 538			newval = mod;
 539			break;
 540		case mod:
 541			newval = yes;
 542			break;
 543		case yes:
 544			newval = no;
 545			break;
 546		}
 547		if (sym_set_tristate_value(sym, newval))
 548			break;
 549	} while (oldval != newval);
 550	return newval;
 551}
 552
 553bool sym_string_valid(struct symbol *sym, const char *str)
 554{
 555	signed char ch;
 556
 557	switch (sym->type) {
 558	case S_STRING:
 559		return true;
 560	case S_INT:
 561		ch = *str++;
 562		if (ch == '-')
 563			ch = *str++;
 564		if (!isdigit(ch))
 565			return false;
 566		if (ch == '0' && *str != 0)
 567			return false;
 568		while ((ch = *str++)) {
 569			if (!isdigit(ch))
 570				return false;
 571		}
 572		return true;
 573	case S_HEX:
 574		if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
 575			str += 2;
 576		ch = *str++;
 577		do {
 578			if (!isxdigit(ch))
 579				return false;
 580		} while ((ch = *str++));
 581		return true;
 582	case S_BOOLEAN:
 583	case S_TRISTATE:
 584		switch (str[0]) {
 585		case 'y': case 'Y':
 586		case 'm': case 'M':
 587		case 'n': case 'N':
 588			return true;
 589		}
 590		return false;
 591	default:
 592		return false;
 593	}
 594}
 595
 596bool sym_string_within_range(struct symbol *sym, const char *str)
 597{
 598	struct property *prop;
 599	long long val;
 600
 601	switch (sym->type) {
 602	case S_STRING:
 603		return sym_string_valid(sym, str);
 604	case S_INT:
 605		if (!sym_string_valid(sym, str))
 606			return false;
 607		prop = sym_get_range_prop(sym);
 608		if (!prop)
 609			return true;
 610		val = strtoll(str, NULL, 10);
 611		return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
 612		       val <= sym_get_range_val(prop->expr->right.sym, 10);
 613	case S_HEX:
 614		if (!sym_string_valid(sym, str))
 615			return false;
 616		prop = sym_get_range_prop(sym);
 617		if (!prop)
 618			return true;
 619		val = strtoll(str, NULL, 16);
 620		return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
 621		       val <= sym_get_range_val(prop->expr->right.sym, 16);
 622	case S_BOOLEAN:
 623	case S_TRISTATE:
 624		switch (str[0]) {
 625		case 'y': case 'Y':
 626			return sym_tristate_within_range(sym, yes);
 627		case 'm': case 'M':
 628			return sym_tristate_within_range(sym, mod);
 629		case 'n': case 'N':
 630			return sym_tristate_within_range(sym, no);
 631		}
 632		return false;
 633	default:
 634		return false;
 635	}
 636}
 637
 638bool sym_set_string_value(struct symbol *sym, const char *newval)
 639{
 640	const char *oldval;
 641	char *val;
 642	int size;
 643
 644	switch (sym->type) {
 645	case S_BOOLEAN:
 646	case S_TRISTATE:
 647		switch (newval[0]) {
 648		case 'y': case 'Y':
 649			return sym_set_tristate_value(sym, yes);
 650		case 'm': case 'M':
 651			return sym_set_tristate_value(sym, mod);
 652		case 'n': case 'N':
 653			return sym_set_tristate_value(sym, no);
 654		}
 655		return false;
 656	default:
 657		;
 658	}
 659
 660	if (!sym_string_within_range(sym, newval))
 661		return false;
 662
 663	if (!(sym->flags & SYMBOL_DEF_USER)) {
 664		sym->flags |= SYMBOL_DEF_USER;
 665		sym_set_changed(sym);
 666	}
 667
 668	oldval = sym->def[S_DEF_USER].val;
 669	size = strlen(newval) + 1;
 670	if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
 671		size += 2;
 672		sym->def[S_DEF_USER].val = val = xmalloc(size);
 673		*val++ = '0';
 674		*val++ = 'x';
 675	} else if (!oldval || strcmp(oldval, newval))
 676		sym->def[S_DEF_USER].val = val = xmalloc(size);
 677	else
 678		return true;
 679
 680	strcpy(val, newval);
 681	free((void *)oldval);
 682	sym_clear_all_valid();
 683
 684	return true;
 685}
 686
 687/*
 688 * Find the default value associated to a symbol.
 689 * For tristate symbol handle the modules=n case
 690 * in which case "m" becomes "y".
 691 * If the symbol does not have any default then fallback
 692 * to the fixed default values.
 693 */
 694const char *sym_get_string_default(struct symbol *sym)
 695{
 696	struct property *prop;
 697	struct symbol *ds;
 698	const char *str;
 699	tristate val;
 700
 701	sym_calc_visibility(sym);
 702	sym_calc_value(modules_sym);
 703	val = symbol_no.curr.tri;
 704	str = symbol_empty.curr.val;
 705
 706	/* If symbol has a default value look it up */
 707	prop = sym_get_default_prop(sym);
 708	if (prop != NULL) {
 709		switch (sym->type) {
 710		case S_BOOLEAN:
 711		case S_TRISTATE:
 712			/* The visibility may limit the value from yes => mod */
 713			val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
 714			break;
 715		default:
 716			/*
 717			 * The following fails to handle the situation
 718			 * where a default value is further limited by
 719			 * the valid range.
 720			 */
 721			ds = prop_get_symbol(prop);
 722			if (ds != NULL) {
 723				sym_calc_value(ds);
 724				str = (const char *)ds->curr.val;
 725			}
 726		}
 727	}
 728
 729	/* Handle select statements */
 730	val = EXPR_OR(val, sym->rev_dep.tri);
 731
 732	/* transpose mod to yes if modules are not enabled */
 733	if (val == mod)
 734		if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
 735			val = yes;
 736
 737	/* transpose mod to yes if type is bool */
 738	if (sym->type == S_BOOLEAN && val == mod)
 739		val = yes;
 740
 741	/* adjust the default value if this symbol is implied by another */
 742	if (val < sym->implied.tri)
 743		val = sym->implied.tri;
 744
 745	switch (sym->type) {
 746	case S_BOOLEAN:
 747	case S_TRISTATE:
 748		switch (val) {
 749		case no: return "n";
 750		case mod: return "m";
 751		case yes: return "y";
 752		}
 753	case S_INT:
 754	case S_HEX:
 755		return str;
 756	case S_STRING:
 757		return str;
 758	case S_UNKNOWN:
 759		break;
 760	}
 761	return "";
 762}
 763
 764const char *sym_get_string_value(struct symbol *sym)
 765{
 766	tristate val;
 767
 768	switch (sym->type) {
 769	case S_BOOLEAN:
 770	case S_TRISTATE:
 771		val = sym_get_tristate_value(sym);
 772		switch (val) {
 773		case no:
 774			return "n";
 775		case mod:
 776			sym_calc_value(modules_sym);
 777			return (modules_sym->curr.tri == no) ? "n" : "m";
 778		case yes:
 779			return "y";
 780		}
 781		break;
 782	default:
 783		;
 784	}
 785	return (const char *)sym->curr.val;
 786}
 787
 788bool sym_is_changeable(struct symbol *sym)
 789{
 790	return sym->visible > sym->rev_dep.tri;
 791}
 792
 793static unsigned strhash(const char *s)
 794{
 795	/* fnv32 hash */
 796	unsigned hash = 2166136261U;
 797	for (; *s; s++)
 798		hash = (hash ^ *s) * 0x01000193;
 799	return hash;
 800}
 801
 802struct symbol *sym_lookup(const char *name, int flags)
 803{
 804	struct symbol *symbol;
 805	char *new_name;
 806	int hash;
 807
 808	if (name) {
 809		if (name[0] && !name[1]) {
 810			switch (name[0]) {
 811			case 'y': return &symbol_yes;
 812			case 'm': return &symbol_mod;
 813			case 'n': return &symbol_no;
 814			}
 815		}
 816		hash = strhash(name) % SYMBOL_HASHSIZE;
 817
 818		for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 819			if (symbol->name &&
 820			    !strcmp(symbol->name, name) &&
 821			    (flags ? symbol->flags & flags
 822				   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
 823				return symbol;
 824		}
 825		new_name = xstrdup(name);
 826	} else {
 827		new_name = NULL;
 828		hash = 0;
 829	}
 830
 831	symbol = xmalloc(sizeof(*symbol));
 832	memset(symbol, 0, sizeof(*symbol));
 833	symbol->name = new_name;
 834	symbol->type = S_UNKNOWN;
 835	symbol->flags |= flags;
 836
 837	symbol->next = symbol_hash[hash];
 838	symbol_hash[hash] = symbol;
 839
 840	return symbol;
 841}
 842
 843struct symbol *sym_find(const char *name)
 844{
 845	struct symbol *symbol = NULL;
 846	int hash = 0;
 847
 848	if (!name)
 849		return NULL;
 850
 851	if (name[0] && !name[1]) {
 852		switch (name[0]) {
 853		case 'y': return &symbol_yes;
 854		case 'm': return &symbol_mod;
 855		case 'n': return &symbol_no;
 856		}
 857	}
 858	hash = strhash(name) % SYMBOL_HASHSIZE;
 859
 860	for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
 861		if (symbol->name &&
 862		    !strcmp(symbol->name, name) &&
 863		    !(symbol->flags & SYMBOL_CONST))
 864				break;
 865	}
 866
 867	return symbol;
 868}
 869
 870const char *sym_escape_string_value(const char *in)
 871{
 872	const char *p;
 873	size_t reslen;
 874	char *res;
 875	size_t l;
 876
 877	reslen = strlen(in) + strlen("\"\"") + 1;
 878
 879	p = in;
 880	for (;;) {
 881		l = strcspn(p, "\"\\");
 882		p += l;
 883
 884		if (p[0] == '\0')
 885			break;
 886
 887		reslen++;
 888		p++;
 889	}
 890
 891	res = xmalloc(reslen);
 892	res[0] = '\0';
 893
 894	strcat(res, "\"");
 895
 896	p = in;
 897	for (;;) {
 898		l = strcspn(p, "\"\\");
 899		strncat(res, p, l);
 900		p += l;
 901
 902		if (p[0] == '\0')
 903			break;
 904
 905		strcat(res, "\\");
 906		strncat(res, p++, 1);
 907	}
 908
 909	strcat(res, "\"");
 910	return res;
 911}
 912
 913struct sym_match {
 914	struct symbol	*sym;
 915	off_t		so, eo;
 916};
 917
 918/* Compare matched symbols as thus:
 919 * - first, symbols that match exactly
 920 * - then, alphabetical sort
 921 */
 922static int sym_rel_comp(const void *sym1, const void *sym2)
 923{
 924	const struct sym_match *s1 = sym1;
 925	const struct sym_match *s2 = sym2;
 926	int exact1, exact2;
 927
 928	/* Exact match:
 929	 * - if matched length on symbol s1 is the length of that symbol,
 930	 *   then this symbol should come first;
 931	 * - if matched length on symbol s2 is the length of that symbol,
 932	 *   then this symbol should come first.
 933	 * Note: since the search can be a regexp, both symbols may match
 934	 * exactly; if this is the case, we can't decide which comes first,
 935	 * and we fallback to sorting alphabetically.
 936	 */
 937	exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
 938	exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
 939	if (exact1 && !exact2)
 940		return -1;
 941	if (!exact1 && exact2)
 942		return 1;
 943
 944	/* As a fallback, sort symbols alphabetically */
 945	return strcmp(s1->sym->name, s2->sym->name);
 946}
 947
 948struct symbol **sym_re_search(const char *pattern)
 949{
 950	struct symbol *sym, **sym_arr = NULL;
 951	struct sym_match *sym_match_arr = NULL;
 952	int i, cnt, size;
 953	regex_t re;
 954	regmatch_t match[1];
 955
 956	cnt = size = 0;
 957	/* Skip if empty */
 958	if (strlen(pattern) == 0)
 959		return NULL;
 960	if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
 961		return NULL;
 962
 963	for_all_symbols(i, sym) {
 964		if (sym->flags & SYMBOL_CONST || !sym->name)
 965			continue;
 966		if (regexec(&re, sym->name, 1, match, 0))
 967			continue;
 968		if (cnt >= size) {
 969			void *tmp;
 970			size += 16;
 971			tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
 972			if (!tmp)
 973				goto sym_re_search_free;
 974			sym_match_arr = tmp;
 975		}
 976		sym_calc_value(sym);
 977		/* As regexec returned 0, we know we have a match, so
 978		 * we can use match[0].rm_[se]o without further checks
 979		 */
 980		sym_match_arr[cnt].so = match[0].rm_so;
 981		sym_match_arr[cnt].eo = match[0].rm_eo;
 982		sym_match_arr[cnt++].sym = sym;
 983	}
 984	if (sym_match_arr) {
 985		qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
 986		sym_arr = malloc((cnt+1) * sizeof(struct symbol *));
 987		if (!sym_arr)
 988			goto sym_re_search_free;
 989		for (i = 0; i < cnt; i++)
 990			sym_arr[i] = sym_match_arr[i].sym;
 991		sym_arr[cnt] = NULL;
 992	}
 993sym_re_search_free:
 994	/* sym_match_arr can be NULL if no match, but free(NULL) is OK */
 995	free(sym_match_arr);
 996	regfree(&re);
 997
 998	return sym_arr;
 999}
1000
1001/*
1002 * When we check for recursive dependencies we use a stack to save
1003 * current state so we can print out relevant info to user.
1004 * The entries are located on the call stack so no need to free memory.
1005 * Note insert() remove() must always match to properly clear the stack.
1006 */
1007static struct dep_stack {
1008	struct dep_stack *prev, *next;
1009	struct symbol *sym;
1010	struct property *prop;
1011	struct expr **expr;
1012} *check_top;
1013
1014static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1015{
1016	memset(stack, 0, sizeof(*stack));
1017	if (check_top)
1018		check_top->next = stack;
1019	stack->prev = check_top;
1020	stack->sym = sym;
1021	check_top = stack;
1022}
1023
1024static void dep_stack_remove(void)
1025{
1026	check_top = check_top->prev;
1027	if (check_top)
1028		check_top->next = NULL;
1029}
1030
1031/*
1032 * Called when we have detected a recursive dependency.
1033 * check_top point to the top of the stact so we use
1034 * the ->prev pointer to locate the bottom of the stack.
1035 */
1036static void sym_check_print_recursive(struct symbol *last_sym)
1037{
1038	struct dep_stack *stack;
1039	struct symbol *sym, *next_sym;
1040	struct menu *menu = NULL;
1041	struct property *prop;
1042	struct dep_stack cv_stack;
1043
1044	if (sym_is_choice_value(last_sym)) {
1045		dep_stack_insert(&cv_stack, last_sym);
1046		last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1047	}
1048
1049	for (stack = check_top; stack != NULL; stack = stack->prev)
1050		if (stack->sym == last_sym)
1051			break;
1052	if (!stack) {
1053		fprintf(stderr, "unexpected recursive dependency error\n");
1054		return;
1055	}
1056
1057	for (; stack; stack = stack->next) {
1058		sym = stack->sym;
1059		next_sym = stack->next ? stack->next->sym : last_sym;
1060		prop = stack->prop;
1061		if (prop == NULL)
1062			prop = stack->sym->prop;
1063
1064		/* for choice values find the menu entry (used below) */
1065		if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1066			for (prop = sym->prop; prop; prop = prop->next) {
1067				menu = prop->menu;
1068				if (prop->menu)
1069					break;
1070			}
1071		}
1072		if (stack->sym == last_sym)
1073			fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1074				prop->file->name, prop->lineno);
1075
1076		if (sym_is_choice(sym)) {
1077			fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1078				menu->file->name, menu->lineno,
1079				sym->name ? sym->name : "<choice>",
1080				next_sym->name ? next_sym->name : "<choice>");
1081		} else if (sym_is_choice_value(sym)) {
1082			fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1083				menu->file->name, menu->lineno,
1084				sym->name ? sym->name : "<choice>",
1085				next_sym->name ? next_sym->name : "<choice>");
1086		} else if (stack->expr == &sym->dir_dep.expr) {
1087			fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1088				prop->file->name, prop->lineno,
1089				sym->name ? sym->name : "<choice>",
1090				next_sym->name ? next_sym->name : "<choice>");
1091		} else if (stack->expr == &sym->rev_dep.expr) {
1092			fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1093				prop->file->name, prop->lineno,
1094				sym->name ? sym->name : "<choice>",
1095				next_sym->name ? next_sym->name : "<choice>");
1096		} else if (stack->expr == &sym->implied.expr) {
1097			fprintf(stderr, "%s:%d:\tsymbol %s is implied by %s\n",
1098				prop->file->name, prop->lineno,
1099				sym->name ? sym->name : "<choice>",
1100				next_sym->name ? next_sym->name : "<choice>");
1101		} else if (stack->expr) {
1102			fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1103				prop->file->name, prop->lineno,
1104				sym->name ? sym->name : "<choice>",
1105				prop_get_type_name(prop->type),
1106				next_sym->name ? next_sym->name : "<choice>");
1107		} else {
1108			fprintf(stderr, "%s:%d:\tsymbol %s %s is visible depending on %s\n",
1109				prop->file->name, prop->lineno,
1110				sym->name ? sym->name : "<choice>",
1111				prop_get_type_name(prop->type),
1112				next_sym->name ? next_sym->name : "<choice>");
1113		}
1114	}
1115
1116	fprintf(stderr,
1117		"For a resolution refer to Documentation/kbuild/kconfig-language.rst\n"
1118		"subsection \"Kconfig recursive dependency limitations\"\n"
1119		"\n");
1120
1121	if (check_top == &cv_stack)
1122		dep_stack_remove();
1123}
1124
1125static struct symbol *sym_check_expr_deps(struct expr *e)
1126{
1127	struct symbol *sym;
1128
1129	if (!e)
1130		return NULL;
1131	switch (e->type) {
1132	case E_OR:
1133	case E_AND:
1134		sym = sym_check_expr_deps(e->left.expr);
1135		if (sym)
1136			return sym;
1137		return sym_check_expr_deps(e->right.expr);
1138	case E_NOT:
1139		return sym_check_expr_deps(e->left.expr);
1140	case E_EQUAL:
1141	case E_GEQ:
1142	case E_GTH:
1143	case E_LEQ:
1144	case E_LTH:
1145	case E_UNEQUAL:
1146		sym = sym_check_deps(e->left.sym);
1147		if (sym)
1148			return sym;
1149		return sym_check_deps(e->right.sym);
1150	case E_SYMBOL:
1151		return sym_check_deps(e->left.sym);
1152	default:
1153		break;
1154	}
1155	fprintf(stderr, "Oops! How to check %d?\n", e->type);
1156	return NULL;
1157}
1158
1159/* return NULL when dependencies are OK */
1160static struct symbol *sym_check_sym_deps(struct symbol *sym)
1161{
1162	struct symbol *sym2;
1163	struct property *prop;
1164	struct dep_stack stack;
1165
1166	dep_stack_insert(&stack, sym);
1167
1168	stack.expr = &sym->dir_dep.expr;
1169	sym2 = sym_check_expr_deps(sym->dir_dep.expr);
1170	if (sym2)
1171		goto out;
1172
1173	stack.expr = &sym->rev_dep.expr;
1174	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1175	if (sym2)
1176		goto out;
1177
1178	stack.expr = &sym->implied.expr;
1179	sym2 = sym_check_expr_deps(sym->implied.expr);
1180	if (sym2)
1181		goto out;
1182
1183	stack.expr = NULL;
1184
1185	for (prop = sym->prop; prop; prop = prop->next) {
1186		if (prop->type == P_CHOICE || prop->type == P_SELECT ||
1187		    prop->type == P_IMPLY)
1188			continue;
1189		stack.prop = prop;
1190		sym2 = sym_check_expr_deps(prop->visible.expr);
1191		if (sym2)
1192			break;
1193		if (prop->type != P_DEFAULT || sym_is_choice(sym))
1194			continue;
1195		stack.expr = &prop->expr;
1196		sym2 = sym_check_expr_deps(prop->expr);
1197		if (sym2)
1198			break;
1199		stack.expr = NULL;
1200	}
1201
1202out:
1203	dep_stack_remove();
1204
1205	return sym2;
1206}
1207
1208static struct symbol *sym_check_choice_deps(struct symbol *choice)
1209{
1210	struct symbol *sym, *sym2;
1211	struct property *prop;
1212	struct expr *e;
1213	struct dep_stack stack;
1214
1215	dep_stack_insert(&stack, choice);
1216
1217	prop = sym_get_choice_prop(choice);
1218	expr_list_for_each_sym(prop->expr, e, sym)
1219		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1220
1221	choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1222	sym2 = sym_check_sym_deps(choice);
1223	choice->flags &= ~SYMBOL_CHECK;
1224	if (sym2)
1225		goto out;
1226
1227	expr_list_for_each_sym(prop->expr, e, sym) {
1228		sym2 = sym_check_sym_deps(sym);
1229		if (sym2)
1230			break;
1231	}
1232out:
1233	expr_list_for_each_sym(prop->expr, e, sym)
1234		sym->flags &= ~SYMBOL_CHECK;
1235
1236	if (sym2 && sym_is_choice_value(sym2) &&
1237	    prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1238		sym2 = choice;
1239
1240	dep_stack_remove();
1241
1242	return sym2;
1243}
1244
1245struct symbol *sym_check_deps(struct symbol *sym)
1246{
1247	struct symbol *sym2;
1248	struct property *prop;
1249
1250	if (sym->flags & SYMBOL_CHECK) {
1251		sym_check_print_recursive(sym);
1252		return sym;
1253	}
1254	if (sym->flags & SYMBOL_CHECKED)
1255		return NULL;
1256
1257	if (sym_is_choice_value(sym)) {
1258		struct dep_stack stack;
1259
1260		/* for choice groups start the check with main choice symbol */
1261		dep_stack_insert(&stack, sym);
1262		prop = sym_get_choice_prop(sym);
1263		sym2 = sym_check_deps(prop_get_symbol(prop));
1264		dep_stack_remove();
1265	} else if (sym_is_choice(sym)) {
1266		sym2 = sym_check_choice_deps(sym);
1267	} else {
1268		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1269		sym2 = sym_check_sym_deps(sym);
1270		sym->flags &= ~SYMBOL_CHECK;
1271	}
1272
1273	return sym2;
1274}
1275
1276struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1277{
1278	struct property *prop;
1279	struct property **propp;
1280
1281	prop = xmalloc(sizeof(*prop));
1282	memset(prop, 0, sizeof(*prop));
1283	prop->type = type;
1284	prop->sym = sym;
1285	prop->file = current_file;
1286	prop->lineno = zconf_lineno();
1287
1288	/* append property to the prop list of symbol */
1289	if (sym) {
1290		for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1291			;
1292		*propp = prop;
1293	}
1294
1295	return prop;
1296}
1297
1298struct symbol *prop_get_symbol(struct property *prop)
1299{
1300	if (prop->expr && (prop->expr->type == E_SYMBOL ||
1301			   prop->expr->type == E_LIST))
1302		return prop->expr->left.sym;
1303	return NULL;
1304}
1305
1306const char *prop_get_type_name(enum prop_type type)
1307{
1308	switch (type) {
1309	case P_PROMPT:
1310		return "prompt";
1311	case P_COMMENT:
1312		return "comment";
1313	case P_MENU:
1314		return "menu";
1315	case P_DEFAULT:
1316		return "default";
1317	case P_CHOICE:
1318		return "choice";
1319	case P_SELECT:
1320		return "select";
1321	case P_IMPLY:
1322		return "imply";
1323	case P_RANGE:
1324		return "range";
1325	case P_SYMBOL:
1326		return "symbol";
1327	case P_UNKNOWN:
1328		break;
1329	}
1330	return "unknown";
1331}