kconfig/symbol.c
author Titus von Boxberg <titus@v9g.de>
Wed Nov 30 12:07:59 2011 +0100 (2011-11-30)
branch1.13
changeset 2843 aaa46c1a2c2a
parent 2448 a103abae1560
permissions -rw-r--r--
scripts: use CT_CONFIG_SHELL instead of CT_SHELL

CT_SHELL is undefined.
Thus, the generated wrapper scripts are not executable by the kernel
because they do not contain a valid interpreter.
Use CT_CONFIG_SHELL instead.

Signed-off-by: "Titus von Boxberg" <titus@v9g.de>
(transplanted from cf509170838f4e289fe25617e3f3db1d6d6ffc41)
     1 /*
     2  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
     3  * Released under the terms of the GNU GPL v2.0.
     4  */
     5 
     6 #include <ctype.h>
     7 #include <stdlib.h>
     8 #include <string.h>
     9 #include <regex.h>
    10 #include <sys/utsname.h>
    11 
    12 #define LKC_DIRECT_LINK
    13 #include "lkc.h"
    14 
    15 struct symbol symbol_yes = {
    16 	.name = "y",
    17 	.curr = { "y", yes },
    18 	.flags = SYMBOL_CONST|SYMBOL_VALID,
    19 }, symbol_mod = {
    20 	.name = "m",
    21 	.curr = { "m", mod },
    22 	.flags = SYMBOL_CONST|SYMBOL_VALID,
    23 }, symbol_no = {
    24 	.name = "n",
    25 	.curr = { "n", no },
    26 	.flags = SYMBOL_CONST|SYMBOL_VALID,
    27 }, symbol_empty = {
    28 	.name = "",
    29 	.curr = { "", no },
    30 	.flags = SYMBOL_VALID,
    31 };
    32 
    33 struct symbol *sym_defconfig_list;
    34 struct symbol *modules_sym;
    35 tristate modules_val;
    36 
    37 struct expr *sym_env_list;
    38 
    39 static void sym_add_default(struct symbol *sym, const char *def)
    40 {
    41 	struct property *prop = prop_alloc(P_DEFAULT, sym);
    42 
    43 	prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST));
    44 }
    45 
    46 void sym_init(void)
    47 {
    48 	struct symbol *sym;
    49 	struct utsname uts;
    50 	static bool inited = false;
    51 
    52 	if (inited)
    53 		return;
    54 	inited = true;
    55 
    56 	uname(&uts);
    57 
    58 	sym = sym_lookup("UNAME_RELEASE", 0);
    59 	sym->type = S_STRING;
    60 	sym->flags |= SYMBOL_AUTO;
    61 	sym_add_default(sym, uts.release);
    62 }
    63 
    64 enum symbol_type sym_get_type(struct symbol *sym)
    65 {
    66 	enum symbol_type type = sym->type;
    67 
    68 	if (type == S_TRISTATE) {
    69 		if (sym_is_choice_value(sym) && sym->visible == yes)
    70 			type = S_BOOLEAN;
    71 		else if (modules_val == no)
    72 			type = S_BOOLEAN;
    73 	}
    74 	return type;
    75 }
    76 
    77 const char *sym_type_name(enum symbol_type type)
    78 {
    79 	switch (type) {
    80 	case S_BOOLEAN:
    81 		return "boolean";
    82 	case S_TRISTATE:
    83 		return "tristate";
    84 	case S_INT:
    85 		return "integer";
    86 	case S_HEX:
    87 		return "hex";
    88 	case S_STRING:
    89 		return "string";
    90 	case S_UNKNOWN:
    91 		return "unknown";
    92 	case S_OTHER:
    93 		break;
    94 	}
    95 	return "???";
    96 }
    97 
    98 struct property *sym_get_choice_prop(struct symbol *sym)
    99 {
   100 	struct property *prop;
   101 
   102 	for_all_choices(sym, prop)
   103 		return prop;
   104 	return NULL;
   105 }
   106 
   107 struct property *sym_get_env_prop(struct symbol *sym)
   108 {
   109 	struct property *prop;
   110 
   111 	for_all_properties(sym, prop, P_ENV)
   112 		return prop;
   113 	return NULL;
   114 }
   115 
   116 struct property *sym_get_default_prop(struct symbol *sym)
   117 {
   118 	struct property *prop;
   119 
   120 	for_all_defaults(sym, prop) {
   121 		prop->visible.tri = expr_calc_value(prop->visible.expr);
   122 		if (prop->visible.tri != no)
   123 			return prop;
   124 	}
   125 	return NULL;
   126 }
   127 
   128 static struct property *sym_get_range_prop(struct symbol *sym)
   129 {
   130 	struct property *prop;
   131 
   132 	for_all_properties(sym, prop, P_RANGE) {
   133 		prop->visible.tri = expr_calc_value(prop->visible.expr);
   134 		if (prop->visible.tri != no)
   135 			return prop;
   136 	}
   137 	return NULL;
   138 }
   139 
   140 static int sym_get_range_val(struct symbol *sym, int base)
   141 {
   142 	sym_calc_value(sym);
   143 	switch (sym->type) {
   144 	case S_INT:
   145 		base = 10;
   146 		break;
   147 	case S_HEX:
   148 		base = 16;
   149 		break;
   150 	default:
   151 		break;
   152 	}
   153 	return strtol(sym->curr.val, NULL, base);
   154 }
   155 
   156 static void sym_validate_range(struct symbol *sym)
   157 {
   158 	struct property *prop;
   159 	int base, val, val2;
   160 	char str[64];
   161 
   162 	switch (sym->type) {
   163 	case S_INT:
   164 		base = 10;
   165 		break;
   166 	case S_HEX:
   167 		base = 16;
   168 		break;
   169 	default:
   170 		return;
   171 	}
   172 	prop = sym_get_range_prop(sym);
   173 	if (!prop)
   174 		return;
   175 	val = strtol(sym->curr.val, NULL, base);
   176 	val2 = sym_get_range_val(prop->expr->left.sym, base);
   177 	if (val >= val2) {
   178 		val2 = sym_get_range_val(prop->expr->right.sym, base);
   179 		if (val <= val2)
   180 			return;
   181 	}
   182 	if (sym->type == S_INT)
   183 		sprintf(str, "%d", val2);
   184 	else
   185 		sprintf(str, "0x%x", val2);
   186 	sym->curr.val = strdup(str);
   187 }
   188 
   189 static void sym_calc_visibility(struct symbol *sym)
   190 {
   191 	struct property *prop;
   192 	tristate tri;
   193 
   194 	/* any prompt visible? */
   195 	tri = no;
   196 	for_all_prompts(sym, prop) {
   197 		prop->visible.tri = expr_calc_value(prop->visible.expr);
   198 		tri = EXPR_OR(tri, prop->visible.tri);
   199 	}
   200 	if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
   201 		tri = yes;
   202 	if (sym->visible != tri) {
   203 		sym->visible = tri;
   204 		sym_set_changed(sym);
   205 	}
   206 	if (sym_is_choice_value(sym))
   207 		return;
   208 	/* defaulting to "yes" if no explicit "depends on" are given */
   209 	tri = yes;
   210 	if (sym->dir_dep.expr)
   211 		tri = expr_calc_value(sym->dir_dep.expr);
   212 	if (tri == mod)
   213 		tri = yes;
   214 	if (sym->dir_dep.tri != tri) {
   215 		sym->dir_dep.tri = tri;
   216 		sym_set_changed(sym);
   217 	}
   218 	tri = no;
   219 	if (sym->rev_dep.expr)
   220 		tri = expr_calc_value(sym->rev_dep.expr);
   221 	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
   222 		tri = yes;
   223 	if (sym->rev_dep.tri != tri) {
   224 		sym->rev_dep.tri = tri;
   225 		sym_set_changed(sym);
   226 	}
   227 }
   228 
   229 /*
   230  * Find the default symbol for a choice.
   231  * First try the default values for the choice symbol
   232  * Next locate the first visible choice value
   233  * Return NULL if none was found
   234  */
   235 struct symbol *sym_choice_default(struct symbol *sym)
   236 {
   237 	struct symbol *def_sym;
   238 	struct property *prop;
   239 	struct expr *e;
   240 
   241 	/* any of the defaults visible? */
   242 	for_all_defaults(sym, prop) {
   243 		prop->visible.tri = expr_calc_value(prop->visible.expr);
   244 		if (prop->visible.tri == no)
   245 			continue;
   246 		def_sym = prop_get_symbol(prop);
   247 		if (def_sym->visible != no)
   248 			return def_sym;
   249 	}
   250 
   251 	/* just get the first visible value */
   252 	prop = sym_get_choice_prop(sym);
   253 	expr_list_for_each_sym(prop->expr, e, def_sym)
   254 		if (def_sym->visible != no)
   255 			return def_sym;
   256 
   257 	/* failed to locate any defaults */
   258 	return NULL;
   259 }
   260 
   261 static struct symbol *sym_calc_choice(struct symbol *sym)
   262 {
   263 	struct symbol *def_sym;
   264 	struct property *prop;
   265 	struct expr *e;
   266 
   267 	/* first calculate all choice values' visibilities */
   268 	prop = sym_get_choice_prop(sym);
   269 	expr_list_for_each_sym(prop->expr, e, def_sym)
   270 		sym_calc_visibility(def_sym);
   271 
   272 	/* is the user choice visible? */
   273 	def_sym = sym->def[S_DEF_USER].val;
   274 	if (def_sym && def_sym->visible != no)
   275 		return def_sym;
   276 
   277 	def_sym = sym_choice_default(sym);
   278 
   279 	if (def_sym == NULL)
   280 		/* no choice? reset tristate value */
   281 		sym->curr.tri = no;
   282 
   283 	return def_sym;
   284 }
   285 
   286 void sym_calc_value(struct symbol *sym)
   287 {
   288 	struct symbol_value newval, oldval;
   289 	struct property *prop;
   290 	struct expr *e;
   291 
   292 	if (!sym)
   293 		return;
   294 
   295 	if (sym->flags & SYMBOL_VALID)
   296 		return;
   297 	sym->flags |= SYMBOL_VALID;
   298 
   299 	oldval = sym->curr;
   300 
   301 	switch (sym->type) {
   302 	case S_INT:
   303 	case S_HEX:
   304 	case S_STRING:
   305 		newval = symbol_empty.curr;
   306 		break;
   307 	case S_BOOLEAN:
   308 	case S_TRISTATE:
   309 		newval = symbol_no.curr;
   310 		break;
   311 	default:
   312 		sym->curr.val = sym->name;
   313 		sym->curr.tri = no;
   314 		return;
   315 	}
   316 	if (!sym_is_choice_value(sym))
   317 		sym->flags &= ~SYMBOL_WRITE;
   318 
   319 	sym_calc_visibility(sym);
   320 
   321 	/* set default if recursively called */
   322 	sym->curr = newval;
   323 
   324 	switch (sym_get_type(sym)) {
   325 	case S_BOOLEAN:
   326 	case S_TRISTATE:
   327 		if (sym_is_choice_value(sym) && sym->visible == yes) {
   328 			prop = sym_get_choice_prop(sym);
   329 			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
   330 		} else {
   331 			if (sym->visible != no) {
   332 				/* if the symbol is visible use the user value
   333 				 * if available, otherwise try the default value
   334 				 */
   335 				sym->flags |= SYMBOL_WRITE;
   336 				if (sym_has_value(sym)) {
   337 					newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
   338 							      sym->visible);
   339 					goto calc_newval;
   340 				}
   341 			}
   342 			if (sym->rev_dep.tri != no)
   343 				sym->flags |= SYMBOL_WRITE;
   344 			if (!sym_is_choice(sym)) {
   345 				prop = sym_get_default_prop(sym);
   346 				if (prop) {
   347 					sym->flags |= SYMBOL_WRITE;
   348 					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
   349 							      prop->visible.tri);
   350 				}
   351 			}
   352 		calc_newval:
   353 			if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
   354 				struct expr *e;
   355 				e = expr_simplify_unmet_dep(sym->rev_dep.expr,
   356 				    sym->dir_dep.expr);
   357 				fprintf(stderr, "warning: (");
   358 				expr_fprint(e, stderr);
   359 				fprintf(stderr, ") selects %s which has unmet direct dependencies (",
   360 					sym->name);
   361 				expr_fprint(sym->dir_dep.expr, stderr);
   362 				fprintf(stderr, ")\n");
   363 				expr_free(e);
   364 			}
   365 			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
   366 		}
   367 		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
   368 			newval.tri = yes;
   369 		break;
   370 	case S_STRING:
   371 	case S_HEX:
   372 	case S_INT:
   373 		if (sym->visible != no) {
   374 			sym->flags |= SYMBOL_WRITE;
   375 			if (sym_has_value(sym)) {
   376 				newval.val = sym->def[S_DEF_USER].val;
   377 				break;
   378 			}
   379 		}
   380 		prop = sym_get_default_prop(sym);
   381 		if (prop) {
   382 			struct symbol *ds = prop_get_symbol(prop);
   383 			if (ds) {
   384 				sym->flags |= SYMBOL_WRITE;
   385 				sym_calc_value(ds);
   386 				newval.val = ds->curr.val;
   387 			}
   388 		}
   389 		break;
   390 	default:
   391 		;
   392 	}
   393 
   394 	sym->curr = newval;
   395 	if (sym_is_choice(sym) && newval.tri == yes)
   396 		sym->curr.val = sym_calc_choice(sym);
   397 	sym_validate_range(sym);
   398 
   399 	if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
   400 		sym_set_changed(sym);
   401 		if (modules_sym == sym) {
   402 			sym_set_all_changed();
   403 			modules_val = modules_sym->curr.tri;
   404 		}
   405 	}
   406 
   407 	if (sym_is_choice(sym)) {
   408 		struct symbol *choice_sym;
   409 
   410 		prop = sym_get_choice_prop(sym);
   411 		expr_list_for_each_sym(prop->expr, e, choice_sym) {
   412 			if ((sym->flags & SYMBOL_WRITE) &&
   413 			    choice_sym->visible != no)
   414 				choice_sym->flags |= SYMBOL_WRITE;
   415 			if (sym->flags & SYMBOL_CHANGED)
   416 				sym_set_changed(choice_sym);
   417 		}
   418 	}
   419 
   420 	if (sym->flags & SYMBOL_AUTO)
   421 		sym->flags &= ~SYMBOL_WRITE;
   422 }
   423 
   424 void sym_clear_all_valid(void)
   425 {
   426 	struct symbol *sym;
   427 	int i;
   428 
   429 	for_all_symbols(i, sym)
   430 		sym->flags &= ~SYMBOL_VALID;
   431 	sym_add_change_count(1);
   432 	if (modules_sym)
   433 		sym_calc_value(modules_sym);
   434 }
   435 
   436 void sym_set_changed(struct symbol *sym)
   437 {
   438 	struct property *prop;
   439 
   440 	sym->flags |= SYMBOL_CHANGED;
   441 	for (prop = sym->prop; prop; prop = prop->next) {
   442 		if (prop->menu)
   443 			prop->menu->flags |= MENU_CHANGED;
   444 	}
   445 }
   446 
   447 void sym_set_all_changed(void)
   448 {
   449 	struct symbol *sym;
   450 	int i;
   451 
   452 	for_all_symbols(i, sym)
   453 		sym_set_changed(sym);
   454 }
   455 
   456 bool sym_tristate_within_range(struct symbol *sym, tristate val)
   457 {
   458 	int type = sym_get_type(sym);
   459 
   460 	if (sym->visible == no)
   461 		return false;
   462 
   463 	if (type != S_BOOLEAN && type != S_TRISTATE)
   464 		return false;
   465 
   466 	if (type == S_BOOLEAN && val == mod)
   467 		return false;
   468 	if (sym->visible <= sym->rev_dep.tri)
   469 		return false;
   470 	if (sym_is_choice_value(sym) && sym->visible == yes)
   471 		return val == yes;
   472 	return val >= sym->rev_dep.tri && val <= sym->visible;
   473 }
   474 
   475 bool sym_set_tristate_value(struct symbol *sym, tristate val)
   476 {
   477 	tristate oldval = sym_get_tristate_value(sym);
   478 
   479 	if (oldval != val && !sym_tristate_within_range(sym, val))
   480 		return false;
   481 
   482 	if (!(sym->flags & SYMBOL_DEF_USER)) {
   483 		sym->flags |= SYMBOL_DEF_USER;
   484 		sym_set_changed(sym);
   485 	}
   486 	/*
   487 	 * setting a choice value also resets the new flag of the choice
   488 	 * symbol and all other choice values.
   489 	 */
   490 	if (sym_is_choice_value(sym) && val == yes) {
   491 		struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
   492 		struct property *prop;
   493 		struct expr *e;
   494 
   495 		cs->def[S_DEF_USER].val = sym;
   496 		cs->flags |= SYMBOL_DEF_USER;
   497 		prop = sym_get_choice_prop(cs);
   498 		for (e = prop->expr; e; e = e->left.expr) {
   499 			if (e->right.sym->visible != no)
   500 				e->right.sym->flags |= SYMBOL_DEF_USER;
   501 		}
   502 	}
   503 
   504 	sym->def[S_DEF_USER].tri = val;
   505 	if (oldval != val)
   506 		sym_clear_all_valid();
   507 
   508 	return true;
   509 }
   510 
   511 tristate sym_toggle_tristate_value(struct symbol *sym)
   512 {
   513 	tristate oldval, newval;
   514 
   515 	oldval = newval = sym_get_tristate_value(sym);
   516 	do {
   517 		switch (newval) {
   518 		case no:
   519 			newval = mod;
   520 			break;
   521 		case mod:
   522 			newval = yes;
   523 			break;
   524 		case yes:
   525 			newval = no;
   526 			break;
   527 		}
   528 		if (sym_set_tristate_value(sym, newval))
   529 			break;
   530 	} while (oldval != newval);
   531 	return newval;
   532 }
   533 
   534 bool sym_string_valid(struct symbol *sym, const char *str)
   535 {
   536 	signed char ch;
   537 
   538 	switch (sym->type) {
   539 	case S_STRING:
   540 		return true;
   541 	case S_INT:
   542 		ch = *str++;
   543 		if (ch == '-')
   544 			ch = *str++;
   545 		if (!isdigit(ch))
   546 			return false;
   547 		if (ch == '0' && *str != 0)
   548 			return false;
   549 		while ((ch = *str++)) {
   550 			if (!isdigit(ch))
   551 				return false;
   552 		}
   553 		return true;
   554 	case S_HEX:
   555 		if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
   556 			str += 2;
   557 		ch = *str++;
   558 		do {
   559 			if (!isxdigit(ch))
   560 				return false;
   561 		} while ((ch = *str++));
   562 		return true;
   563 	case S_BOOLEAN:
   564 	case S_TRISTATE:
   565 		switch (str[0]) {
   566 		case 'y': case 'Y':
   567 		case 'm': case 'M':
   568 		case 'n': case 'N':
   569 			return true;
   570 		}
   571 		return false;
   572 	default:
   573 		return false;
   574 	}
   575 }
   576 
   577 bool sym_string_within_range(struct symbol *sym, const char *str)
   578 {
   579 	struct property *prop;
   580 	int val;
   581 
   582 	switch (sym->type) {
   583 	case S_STRING:
   584 		return sym_string_valid(sym, str);
   585 	case S_INT:
   586 		if (!sym_string_valid(sym, str))
   587 			return false;
   588 		prop = sym_get_range_prop(sym);
   589 		if (!prop)
   590 			return true;
   591 		val = strtol(str, NULL, 10);
   592 		return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
   593 		       val <= sym_get_range_val(prop->expr->right.sym, 10);
   594 	case S_HEX:
   595 		if (!sym_string_valid(sym, str))
   596 			return false;
   597 		prop = sym_get_range_prop(sym);
   598 		if (!prop)
   599 			return true;
   600 		val = strtol(str, NULL, 16);
   601 		return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
   602 		       val <= sym_get_range_val(prop->expr->right.sym, 16);
   603 	case S_BOOLEAN:
   604 	case S_TRISTATE:
   605 		switch (str[0]) {
   606 		case 'y': case 'Y':
   607 			return sym_tristate_within_range(sym, yes);
   608 		case 'm': case 'M':
   609 			return sym_tristate_within_range(sym, mod);
   610 		case 'n': case 'N':
   611 			return sym_tristate_within_range(sym, no);
   612 		}
   613 		return false;
   614 	default:
   615 		return false;
   616 	}
   617 }
   618 
   619 bool sym_set_string_value(struct symbol *sym, const char *newval)
   620 {
   621 	const char *oldval;
   622 	char *val;
   623 	int size;
   624 
   625 	switch (sym->type) {
   626 	case S_BOOLEAN:
   627 	case S_TRISTATE:
   628 		switch (newval[0]) {
   629 		case 'y': case 'Y':
   630 			return sym_set_tristate_value(sym, yes);
   631 		case 'm': case 'M':
   632 			return sym_set_tristate_value(sym, mod);
   633 		case 'n': case 'N':
   634 			return sym_set_tristate_value(sym, no);
   635 		}
   636 		return false;
   637 	default:
   638 		;
   639 	}
   640 
   641 	if (!sym_string_within_range(sym, newval))
   642 		return false;
   643 
   644 	if (!(sym->flags & SYMBOL_DEF_USER)) {
   645 		sym->flags |= SYMBOL_DEF_USER;
   646 		sym_set_changed(sym);
   647 	}
   648 
   649 	oldval = sym->def[S_DEF_USER].val;
   650 	size = strlen(newval) + 1;
   651 	if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
   652 		size += 2;
   653 		sym->def[S_DEF_USER].val = val = malloc(size);
   654 		*val++ = '0';
   655 		*val++ = 'x';
   656 	} else if (!oldval || strcmp(oldval, newval))
   657 		sym->def[S_DEF_USER].val = val = malloc(size);
   658 	else
   659 		return true;
   660 
   661 	strcpy(val, newval);
   662 	free((void *)oldval);
   663 	sym_clear_all_valid();
   664 
   665 	return true;
   666 }
   667 
   668 /*
   669  * Find the default value associated to a symbol.
   670  * For tristate symbol handle the modules=n case
   671  * in which case "m" becomes "y".
   672  * If the symbol does not have any default then fallback
   673  * to the fixed default values.
   674  */
   675 const char *sym_get_string_default(struct symbol *sym)
   676 {
   677 	struct property *prop;
   678 	struct symbol *ds;
   679 	const char *str;
   680 	tristate val;
   681 
   682 	sym_calc_visibility(sym);
   683 	sym_calc_value(modules_sym);
   684 	val = symbol_no.curr.tri;
   685 	str = symbol_empty.curr.val;
   686 
   687 	/* If symbol has a default value look it up */
   688 	prop = sym_get_default_prop(sym);
   689 	if (prop != NULL) {
   690 		switch (sym->type) {
   691 		case S_BOOLEAN:
   692 		case S_TRISTATE:
   693 			/* The visibility may limit the value from yes => mod */
   694 			val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
   695 			break;
   696 		default:
   697 			/*
   698 			 * The following fails to handle the situation
   699 			 * where a default value is further limited by
   700 			 * the valid range.
   701 			 */
   702 			ds = prop_get_symbol(prop);
   703 			if (ds != NULL) {
   704 				sym_calc_value(ds);
   705 				str = (const char *)ds->curr.val;
   706 			}
   707 		}
   708 	}
   709 
   710 	/* Handle select statements */
   711 	val = EXPR_OR(val, sym->rev_dep.tri);
   712 
   713 	/* transpose mod to yes if modules are not enabled */
   714 	if (val == mod)
   715 		if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
   716 			val = yes;
   717 
   718 	/* transpose mod to yes if type is bool */
   719 	if (sym->type == S_BOOLEAN && val == mod)
   720 		val = yes;
   721 
   722 	switch (sym->type) {
   723 	case S_BOOLEAN:
   724 	case S_TRISTATE:
   725 		switch (val) {
   726 		case no: return "n";
   727 		case mod: return "m";
   728 		case yes: return "y";
   729 		}
   730 	case S_INT:
   731 	case S_HEX:
   732 		return str;
   733 	case S_STRING:
   734 		return str;
   735 	case S_OTHER:
   736 	case S_UNKNOWN:
   737 		break;
   738 	}
   739 	return "";
   740 }
   741 
   742 const char *sym_get_string_value(struct symbol *sym)
   743 {
   744 	tristate val;
   745 
   746 	switch (sym->type) {
   747 	case S_BOOLEAN:
   748 	case S_TRISTATE:
   749 		val = sym_get_tristate_value(sym);
   750 		switch (val) {
   751 		case no:
   752 			return "n";
   753 		case mod:
   754 			return "m";
   755 		case yes:
   756 			return "y";
   757 		}
   758 		break;
   759 	default:
   760 		;
   761 	}
   762 	return (const char *)sym->curr.val;
   763 }
   764 
   765 bool sym_is_changable(struct symbol *sym)
   766 {
   767 	return sym->visible > sym->rev_dep.tri;
   768 }
   769 
   770 static unsigned strhash(const char *s)
   771 {
   772 	/* fnv32 hash */
   773 	unsigned hash = 2166136261U;
   774 	for (; *s; s++)
   775 		hash = (hash ^ *s) * 0x01000193;
   776 	return hash;
   777 }
   778 
   779 struct symbol *sym_lookup(const char *name, int flags)
   780 {
   781 	struct symbol *symbol;
   782 	char *new_name;
   783 	int hash;
   784 
   785 	if (name) {
   786 		if (name[0] && !name[1]) {
   787 			switch (name[0]) {
   788 			case 'y': return &symbol_yes;
   789 			case 'm': return &symbol_mod;
   790 			case 'n': return &symbol_no;
   791 			}
   792 		}
   793 		hash = strhash(name) % SYMBOL_HASHSIZE;
   794 
   795 		for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
   796 			if (symbol->name &&
   797 			    !strcmp(symbol->name, name) &&
   798 			    (flags ? symbol->flags & flags
   799 				   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
   800 				return symbol;
   801 		}
   802 		new_name = strdup(name);
   803 	} else {
   804 		new_name = NULL;
   805 		hash = 0;
   806 	}
   807 
   808 	symbol = malloc(sizeof(*symbol));
   809 	memset(symbol, 0, sizeof(*symbol));
   810 	symbol->name = new_name;
   811 	symbol->type = S_UNKNOWN;
   812 	symbol->flags |= flags;
   813 
   814 	symbol->next = symbol_hash[hash];
   815 	symbol_hash[hash] = symbol;
   816 
   817 	return symbol;
   818 }
   819 
   820 struct symbol *sym_find(const char *name)
   821 {
   822 	struct symbol *symbol = NULL;
   823 	int hash = 0;
   824 
   825 	if (!name)
   826 		return NULL;
   827 
   828 	if (name[0] && !name[1]) {
   829 		switch (name[0]) {
   830 		case 'y': return &symbol_yes;
   831 		case 'm': return &symbol_mod;
   832 		case 'n': return &symbol_no;
   833 		}
   834 	}
   835 	hash = strhash(name) % SYMBOL_HASHSIZE;
   836 
   837 	for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
   838 		if (symbol->name &&
   839 		    !strcmp(symbol->name, name) &&
   840 		    !(symbol->flags & SYMBOL_CONST))
   841 				break;
   842 	}
   843 
   844 	return symbol;
   845 }
   846 
   847 /*
   848  * Expand symbol's names embedded in the string given in argument. Symbols'
   849  * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
   850  * the empty string.
   851  */
   852 const char *sym_expand_string_value(const char *in)
   853 {
   854 	const char *src;
   855 	char *res;
   856 	size_t reslen;
   857 
   858 	reslen = strlen(in) + 1;
   859 	res = malloc(reslen);
   860 	res[0] = '\0';
   861 
   862 	while ((src = strchr(in, '$'))) {
   863 		char *p, name[SYMBOL_MAXLENGTH];
   864 		const char *symval = "";
   865 		struct symbol *sym;
   866 		size_t newlen;
   867 
   868 		strncat(res, in, src - in);
   869 		src++;
   870 
   871 		p = name;
   872 		while (isalnum(*src) || *src == '_')
   873 			*p++ = *src++;
   874 		*p = '\0';
   875 
   876 		sym = sym_find(name);
   877 		if (sym != NULL) {
   878 			sym_calc_value(sym);
   879 			symval = sym_get_string_value(sym);
   880 		}
   881 
   882 		newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
   883 		if (newlen > reslen) {
   884 			reslen = newlen;
   885 			res = realloc(res, reslen);
   886 		}
   887 
   888 		strcat(res, symval);
   889 		in = src;
   890 	}
   891 	strcat(res, in);
   892 
   893 	return res;
   894 }
   895 
   896 struct symbol **sym_re_search(const char *pattern)
   897 {
   898 	struct symbol *sym, **sym_arr = NULL;
   899 	int i, cnt, size;
   900 	regex_t re;
   901 
   902 	cnt = size = 0;
   903 	/* Skip if empty */
   904 	if (strlen(pattern) == 0)
   905 		return NULL;
   906 	if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
   907 		return NULL;
   908 
   909 	for_all_symbols(i, sym) {
   910 		if (sym->flags & SYMBOL_CONST || !sym->name)
   911 			continue;
   912 		if (regexec(&re, sym->name, 0, NULL, 0))
   913 			continue;
   914 		if (cnt + 1 >= size) {
   915 			void *tmp = sym_arr;
   916 			size += 16;
   917 			sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
   918 			if (!sym_arr) {
   919 				free(tmp);
   920 				return NULL;
   921 			}
   922 		}
   923 		sym_calc_value(sym);
   924 		sym_arr[cnt++] = sym;
   925 	}
   926 	if (sym_arr)
   927 		sym_arr[cnt] = NULL;
   928 	regfree(&re);
   929 
   930 	return sym_arr;
   931 }
   932 
   933 /*
   934  * When we check for recursive dependencies we use a stack to save
   935  * current state so we can print out relevant info to user.
   936  * The entries are located on the call stack so no need to free memory.
   937  * Note inser() remove() must always match to properly clear the stack.
   938  */
   939 static struct dep_stack {
   940 	struct dep_stack *prev, *next;
   941 	struct symbol *sym;
   942 	struct property *prop;
   943 	struct expr *expr;
   944 } *check_top;
   945 
   946 static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
   947 {
   948 	memset(stack, 0, sizeof(*stack));
   949 	if (check_top)
   950 		check_top->next = stack;
   951 	stack->prev = check_top;
   952 	stack->sym = sym;
   953 	check_top = stack;
   954 }
   955 
   956 static void dep_stack_remove(void)
   957 {
   958 	check_top = check_top->prev;
   959 	if (check_top)
   960 		check_top->next = NULL;
   961 }
   962 
   963 /*
   964  * Called when we have detected a recursive dependency.
   965  * check_top point to the top of the stact so we use
   966  * the ->prev pointer to locate the bottom of the stack.
   967  */
   968 static void sym_check_print_recursive(struct symbol *last_sym)
   969 {
   970 	struct dep_stack *stack;
   971 	struct symbol *sym, *next_sym;
   972 	struct menu *menu = NULL;
   973 	struct property *prop;
   974 	struct dep_stack cv_stack;
   975 
   976 	if (sym_is_choice_value(last_sym)) {
   977 		dep_stack_insert(&cv_stack, last_sym);
   978 		last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
   979 	}
   980 
   981 	for (stack = check_top; stack != NULL; stack = stack->prev)
   982 		if (stack->sym == last_sym)
   983 			break;
   984 	if (!stack) {
   985 		fprintf(stderr, "unexpected recursive dependency error\n");
   986 		return;
   987 	}
   988 
   989 	for (; stack; stack = stack->next) {
   990 		sym = stack->sym;
   991 		next_sym = stack->next ? stack->next->sym : last_sym;
   992 		prop = stack->prop;
   993 		if (prop == NULL)
   994 			prop = stack->sym->prop;
   995 
   996 		/* for choice values find the menu entry (used below) */
   997 		if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
   998 			for (prop = sym->prop; prop; prop = prop->next) {
   999 				menu = prop->menu;
  1000 				if (prop->menu)
  1001 					break;
  1002 			}
  1003 		}
  1004 		if (stack->sym == last_sym)
  1005 			fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
  1006 				prop->file->name, prop->lineno);
  1007 		if (stack->expr) {
  1008 			fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
  1009 				prop->file->name, prop->lineno,
  1010 				sym->name ? sym->name : "<choice>",
  1011 				prop_get_type_name(prop->type),
  1012 				next_sym->name ? next_sym->name : "<choice>");
  1013 		} else if (stack->prop) {
  1014 			fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
  1015 				prop->file->name, prop->lineno,
  1016 				sym->name ? sym->name : "<choice>",
  1017 				next_sym->name ? next_sym->name : "<choice>");
  1018 		} else if (sym_is_choice(sym)) {
  1019 			fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
  1020 				menu->file->name, menu->lineno,
  1021 				sym->name ? sym->name : "<choice>",
  1022 				next_sym->name ? next_sym->name : "<choice>");
  1023 		} else if (sym_is_choice_value(sym)) {
  1024 			fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
  1025 				menu->file->name, menu->lineno,
  1026 				sym->name ? sym->name : "<choice>",
  1027 				next_sym->name ? next_sym->name : "<choice>");
  1028 		} else {
  1029 			fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
  1030 				prop->file->name, prop->lineno,
  1031 				sym->name ? sym->name : "<choice>",
  1032 				next_sym->name ? next_sym->name : "<choice>");
  1033 		}
  1034 	}
  1035 
  1036 	if (check_top == &cv_stack)
  1037 		dep_stack_remove();
  1038 }
  1039 
  1040 static struct symbol *sym_check_expr_deps(struct expr *e)
  1041 {
  1042 	struct symbol *sym;
  1043 
  1044 	if (!e)
  1045 		return NULL;
  1046 	switch (e->type) {
  1047 	case E_OR:
  1048 	case E_AND:
  1049 		sym = sym_check_expr_deps(e->left.expr);
  1050 		if (sym)
  1051 			return sym;
  1052 		return sym_check_expr_deps(e->right.expr);
  1053 	case E_NOT:
  1054 		return sym_check_expr_deps(e->left.expr);
  1055 	case E_EQUAL:
  1056 	case E_UNEQUAL:
  1057 		sym = sym_check_deps(e->left.sym);
  1058 		if (sym)
  1059 			return sym;
  1060 		return sym_check_deps(e->right.sym);
  1061 	case E_SYMBOL:
  1062 		return sym_check_deps(e->left.sym);
  1063 	default:
  1064 		break;
  1065 	}
  1066 	printf("Oops! How to check %d?\n", e->type);
  1067 	return NULL;
  1068 }
  1069 
  1070 /* return NULL when dependencies are OK */
  1071 static struct symbol *sym_check_sym_deps(struct symbol *sym)
  1072 {
  1073 	struct symbol *sym2;
  1074 	struct property *prop;
  1075 	struct dep_stack stack;
  1076 
  1077 	dep_stack_insert(&stack, sym);
  1078 
  1079 	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
  1080 	if (sym2)
  1081 		goto out;
  1082 
  1083 	for (prop = sym->prop; prop; prop = prop->next) {
  1084 		if (prop->type == P_CHOICE || prop->type == P_SELECT)
  1085 			continue;
  1086 		stack.prop = prop;
  1087 		sym2 = sym_check_expr_deps(prop->visible.expr);
  1088 		if (sym2)
  1089 			break;
  1090 		if (prop->type != P_DEFAULT || sym_is_choice(sym))
  1091 			continue;
  1092 		stack.expr = prop->expr;
  1093 		sym2 = sym_check_expr_deps(prop->expr);
  1094 		if (sym2)
  1095 			break;
  1096 		stack.expr = NULL;
  1097 	}
  1098 
  1099 out:
  1100 	dep_stack_remove();
  1101 
  1102 	return sym2;
  1103 }
  1104 
  1105 static struct symbol *sym_check_choice_deps(struct symbol *choice)
  1106 {
  1107 	struct symbol *sym, *sym2;
  1108 	struct property *prop;
  1109 	struct expr *e;
  1110 	struct dep_stack stack;
  1111 
  1112 	dep_stack_insert(&stack, choice);
  1113 
  1114 	prop = sym_get_choice_prop(choice);
  1115 	expr_list_for_each_sym(prop->expr, e, sym)
  1116 		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
  1117 
  1118 	choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
  1119 	sym2 = sym_check_sym_deps(choice);
  1120 	choice->flags &= ~SYMBOL_CHECK;
  1121 	if (sym2)
  1122 		goto out;
  1123 
  1124 	expr_list_for_each_sym(prop->expr, e, sym) {
  1125 		sym2 = sym_check_sym_deps(sym);
  1126 		if (sym2)
  1127 			break;
  1128 	}
  1129 out:
  1130 	expr_list_for_each_sym(prop->expr, e, sym)
  1131 		sym->flags &= ~SYMBOL_CHECK;
  1132 
  1133 	if (sym2 && sym_is_choice_value(sym2) &&
  1134 	    prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
  1135 		sym2 = choice;
  1136 
  1137 	dep_stack_remove();
  1138 
  1139 	return sym2;
  1140 }
  1141 
  1142 struct symbol *sym_check_deps(struct symbol *sym)
  1143 {
  1144 	struct symbol *sym2;
  1145 	struct property *prop;
  1146 
  1147 	if (sym->flags & SYMBOL_CHECK) {
  1148 		sym_check_print_recursive(sym);
  1149 		return sym;
  1150 	}
  1151 	if (sym->flags & SYMBOL_CHECKED)
  1152 		return NULL;
  1153 
  1154 	if (sym_is_choice_value(sym)) {
  1155 		struct dep_stack stack;
  1156 
  1157 		/* for choice groups start the check with main choice symbol */
  1158 		dep_stack_insert(&stack, sym);
  1159 		prop = sym_get_choice_prop(sym);
  1160 		sym2 = sym_check_deps(prop_get_symbol(prop));
  1161 		dep_stack_remove();
  1162 	} else if (sym_is_choice(sym)) {
  1163 		sym2 = sym_check_choice_deps(sym);
  1164 	} else {
  1165 		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
  1166 		sym2 = sym_check_sym_deps(sym);
  1167 		sym->flags &= ~SYMBOL_CHECK;
  1168 	}
  1169 
  1170 	if (sym2 && sym2 == sym)
  1171 		sym2 = NULL;
  1172 
  1173 	return sym2;
  1174 }
  1175 
  1176 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
  1177 {
  1178 	struct property *prop;
  1179 	struct property **propp;
  1180 
  1181 	prop = malloc(sizeof(*prop));
  1182 	memset(prop, 0, sizeof(*prop));
  1183 	prop->type = type;
  1184 	prop->sym = sym;
  1185 	prop->file = current_file;
  1186 	prop->lineno = zconf_lineno();
  1187 
  1188 	/* append property to the prop list of symbol */
  1189 	if (sym) {
  1190 		for (propp = &sym->prop; *propp; propp = &(*propp)->next)
  1191 			;
  1192 		*propp = prop;
  1193 	}
  1194 
  1195 	return prop;
  1196 }
  1197 
  1198 struct symbol *prop_get_symbol(struct property *prop)
  1199 {
  1200 	if (prop->expr && (prop->expr->type == E_SYMBOL ||
  1201 			   prop->expr->type == E_LIST))
  1202 		return prop->expr->left.sym;
  1203 	return NULL;
  1204 }
  1205 
  1206 const char *prop_get_type_name(enum prop_type type)
  1207 {
  1208 	switch (type) {
  1209 	case P_PROMPT:
  1210 		return "prompt";
  1211 	case P_ENV:
  1212 		return "env";
  1213 	case P_COMMENT:
  1214 		return "comment";
  1215 	case P_MENU:
  1216 		return "menu";
  1217 	case P_DEFAULT:
  1218 		return "default";
  1219 	case P_CHOICE:
  1220 		return "choice";
  1221 	case P_SELECT:
  1222 		return "select";
  1223 	case P_RANGE:
  1224 		return "range";
  1225 	case P_SYMBOL:
  1226 		return "symbol";
  1227 	case P_UNKNOWN:
  1228 		break;
  1229 	}
  1230 	return "unknown";
  1231 }
  1232 
  1233 static void prop_add_env(const char *env)
  1234 {
  1235 	struct symbol *sym, *sym2;
  1236 	struct property *prop;
  1237 	char *p;
  1238 
  1239 	sym = current_entry->sym;
  1240 	sym->flags |= SYMBOL_AUTO;
  1241 	for_all_properties(sym, prop, P_ENV) {
  1242 		sym2 = prop_get_symbol(prop);
  1243 		if (strcmp(sym2->name, env))
  1244 			menu_warn(current_entry, "redefining environment symbol from %s",
  1245 				  sym2->name);
  1246 		return;
  1247 	}
  1248 
  1249 	prop = prop_alloc(P_ENV, sym);
  1250 	prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
  1251 
  1252 	sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
  1253 	sym_env_list->right.sym = sym;
  1254 
  1255 	p = getenv(env);
  1256 	if (p)
  1257 		sym_add_default(sym, p);
  1258 }