/*
   * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   * Released under the terms of the GNU GPL v2.0.
   */
  
  #include <sys/stat.h>
  #include <ctype.h>

  #include <errno.h>

  #include <fcntl.h>

  #include <stdarg.h>

  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <time.h>
  #include <unistd.h>

  #include "lkc.h"

  static void conf_warning(const char *fmt, ...)
  	__attribute__ ((format (printf, 1, 2)));

  static void conf_message(const char *fmt, ...)
  	__attribute__ ((format (printf, 1, 2)));

  static const char *conf_filename;
  static int conf_lineno, conf_warnings, conf_unsaved;

  const char conf_defname[] = "arch/$ARCH/defconfig";

  static void conf_warning(const char *fmt, ...)
  {
  	va_list ap;
  	va_start(ap, fmt);
  	fprintf(stderr, "%s:%d:warning: ", conf_filename, conf_lineno);
  	vfprintf(stderr, fmt, ap);
  	fprintf(stderr, "
  ");
  	va_end(ap);
  	conf_warnings++;
  }

  static void conf_default_message_callback(const char *fmt, va_list ap)
  {
  	printf("#
  # ");
  	vprintf(fmt, ap);
  	printf("
  #
  ");
  }
  
  static void (*conf_message_callback) (const char *fmt, va_list ap) =
  	conf_default_message_callback;
  void conf_set_message_callback(void (*fn) (const char *fmt, va_list ap))
  {
  	conf_message_callback = fn;
  }
  
  static void conf_message(const char *fmt, ...)
  {
  	va_list ap;
  
  	va_start(ap, fmt);
  	if (conf_message_callback)
  		conf_message_callback(fmt, ap);
  }

  const char *conf_get_configname(void)
  {
  	char *name = getenv("KCONFIG_CONFIG");
  
  	return name ? name : ".config";
  }

  const char *conf_get_autoconfig_name(void)
  {
  	char *name = getenv("KCONFIG_AUTOCONFIG");
  
  	return name ? name : "include/config/auto.conf";
  }

  static char *conf_expand_value(const char *in)

  {
  	struct symbol *sym;

  	const char *src;

  	static char res_value[SYMBOL_MAXLENGTH];
  	char *dst, name[SYMBOL_MAXLENGTH];
  
  	res_value[0] = 0;
  	dst = name;
  	while ((src = strchr(in, '$'))) {
  		strncat(res_value, in, src - in);
  		src++;
  		dst = name;
  		while (isalnum(*src) || *src == '_')
  			*dst++ = *src++;
  		*dst = 0;
  		sym = sym_lookup(name, 0);
  		sym_calc_value(sym);
  		strcat(res_value, sym_get_string_value(sym));
  		in = src;
  	}
  	strcat(res_value, in);
  
  	return res_value;
  }
  
  char *conf_get_default_confname(void)
  {
  	struct stat buf;
  	static char fullname[PATH_MAX+1];
  	char *env, *name;
  
  	name = conf_expand_value(conf_defname);
  	env = getenv(SRCTREE);
  	if (env) {
  		sprintf(fullname, "%s/%s", env, name);
  		if (!stat(fullname, &buf))
  			return fullname;
  	}
  	return name;
  }

  static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
  {
  	char *p2;
  
  	switch (sym->type) {
  	case S_TRISTATE:
  		if (p[0] == 'm') {
  			sym->def[def].tri = mod;
  			sym->flags |= def_flags;
  			break;
  		}

  		/* fall through */

  	case S_BOOLEAN:
  		if (p[0] == 'y') {
  			sym->def[def].tri = yes;
  			sym->flags |= def_flags;
  			break;
  		}
  		if (p[0] == 'n') {
  			sym->def[def].tri = no;
  			sym->flags |= def_flags;
  			break;
  		}

  		if (def != S_DEF_AUTO)
  			conf_warning("symbol value '%s' invalid for %s",
  				     p, sym->name);

  		return 1;

  	case S_OTHER:
  		if (*p != '"') {
  			for (p2 = p; *p2 && !isspace(*p2); p2++)
  				;
  			sym->type = S_STRING;
  			goto done;
  		}

  		/* fall through */

  	case S_STRING:
  		if (*p++ != '"')
  			break;
  		for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
  			if (*p2 == '"') {
  				*p2 = 0;
  				break;
  			}
  			memmove(p2, p2 + 1, strlen(p2));
  		}
  		if (!p2) {

  			if (def != S_DEF_AUTO)
  				conf_warning("invalid string found");

  			return 1;
  		}

  		/* fall through */

  	case S_INT:
  	case S_HEX:
  	done:
  		if (sym_string_valid(sym, p)) {
  			sym->def[def].val = strdup(p);
  			sym->flags |= def_flags;
  		} else {

  			if (def != S_DEF_AUTO)
  				conf_warning("symbol value '%s' invalid for %s",
  					     p, sym->name);

  			return 1;
  		}
  		break;
  	default:
  		;
  	}
  	return 0;
  }

  #define LINE_GROWTH 16
  static int add_byte(int c, char **lineptr, size_t slen, size_t *n)
  {
  	char *nline;
  	size_t new_size = slen + 1;
  	if (new_size > *n) {
  		new_size += LINE_GROWTH - 1;
  		new_size *= 2;
  		nline = realloc(*lineptr, new_size);
  		if (!nline)
  			return -1;
  
  		*lineptr = nline;
  		*n = new_size;
  	}
  
  	(*lineptr)[slen] = c;
  
  	return 0;
  }
  
  static ssize_t compat_getline(char **lineptr, size_t *n, FILE *stream)
  {
  	char *line = *lineptr;
  	size_t slen = 0;
  
  	for (;;) {
  		int c = getc(stream);
  
  		switch (c) {
  		case '
  ':
  			if (add_byte(c, &line, slen, n) < 0)
  				goto e_out;
  			slen++;
  			/* fall through */
  		case EOF:
  			if (add_byte('\0', &line, slen, n) < 0)
  				goto e_out;
  			*lineptr = line;
  			if (slen == 0)
  				return -1;
  			return slen;
  		default:
  			if (add_byte(c, &line, slen, n) < 0)
  				goto e_out;
  			slen++;
  		}
  	}
  
  e_out:
  	line[slen-1] = '\0';
  	*lineptr = line;
  	return -1;
  }

  int conf_read_simple(const char *name, int def)

  {
  	FILE *in = NULL;

  	char   *line = NULL;
  	size_t  line_asize = 0;

  	char *p, *p2;

  	struct symbol *sym;

  	int i, def_flags;

  
  	if (name) {
  		in = zconf_fopen(name);
  	} else {

  		struct property *prop;

  		name = conf_get_configname();

  		in = zconf_fopen(name);
  		if (in)
  			goto load;

  		sym_add_change_count(1);

  		if (!sym_defconfig_list) {
  			if (modules_sym)
  				sym_calc_value(modules_sym);

  			return 1;

  		}

  
  		for_all_defaults(sym_defconfig_list, prop) {
  			if (expr_calc_value(prop->visible.expr) == no ||
  			    prop->expr->type != E_SYMBOL)
  				continue;
  			name = conf_expand_value(prop->expr->left.sym->name);

  			in = zconf_fopen(name);
  			if (in) {

  				conf_message(_("using defaults found in %s"),
  					 name);

  				goto load;

  			}
  		}
  	}

  	if (!in)
  		return 1;

  load:

  	conf_filename = name;
  	conf_lineno = 0;
  	conf_warnings = 0;
  	conf_unsaved = 0;

  	def_flags = SYMBOL_DEF << def;

  	for_all_symbols(i, sym) {

  		sym->flags |= SYMBOL_CHANGED;
  		sym->flags &= ~(def_flags|SYMBOL_VALID);

  		if (sym_is_choice(sym))
  			sym->flags |= def_flags;

  		switch (sym->type) {
  		case S_INT:
  		case S_HEX:
  		case S_STRING:

  			if (sym->def[def].val)
  				free(sym->def[def].val);

  			/* fall through */

  		default:

  			sym->def[def].val = NULL;
  			sym->def[def].tri = no;

  		}
  	}

  	while (compat_getline(&line, &line_asize, in) != -1) {

  		conf_lineno++;

  		sym = NULL;

  		if (line[0] == '#') {

  			if (memcmp(line + 2, CONFIG_, strlen(CONFIG_)))

  				continue;

  			p = strchr(line + 2 + strlen(CONFIG_), ' ');

  			if (!p)
  				continue;
  			*p++ = 0;
  			if (strncmp(p, "is not set", 10))
  				continue;

  			if (def == S_DEF_USER) {

  				sym = sym_find(line + 2 + strlen(CONFIG_));

  				if (!sym) {
  					sym_add_change_count(1);

  					goto setsym;

  				}

  			} else {

  				sym = sym_lookup(line + 2 + strlen(CONFIG_), 0);

  				if (sym->type == S_UNKNOWN)
  					sym->type = S_BOOLEAN;
  			}
  			if (sym->flags & def_flags) {

  				conf_warning("override: reassigning to symbol %s", sym->name);

  			}
  			switch (sym->type) {
  			case S_BOOLEAN:
  			case S_TRISTATE:

  				sym->def[def].tri = no;
  				sym->flags |= def_flags;

  				break;
  			default:
  				;
  			}

  		} else if (memcmp(line, CONFIG_, strlen(CONFIG_)) == 0) {
  			p = strchr(line + strlen(CONFIG_), '=');

  			if (!p)
  				continue;
  			*p++ = 0;
  			p2 = strchr(p, '
  ');

  			if (p2) {
  				*p2-- = 0;
  				if (*p2 == '\r')
  					*p2 = 0;
  			}

  			if (def == S_DEF_USER) {

  				sym = sym_find(line + strlen(CONFIG_));

  				if (!sym) {
  					sym_add_change_count(1);

  					goto setsym;

  				}

  			} else {

  				sym = sym_lookup(line + strlen(CONFIG_), 0);

  				if (sym->type == S_UNKNOWN)
  					sym->type = S_OTHER;
  			}
  			if (sym->flags & def_flags) {

  				conf_warning("override: reassigning to symbol %s", sym->name);

  			}

  			if (conf_set_sym_val(sym, def, def_flags, p))
  				continue;

  		} else {
  			if (line[0] != '\r' && line[0] != '
  ')
  				conf_warning("unexpected data");

  			continue;
  		}

  setsym:

  		if (sym && sym_is_choice_value(sym)) {
  			struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));

  			switch (sym->def[def].tri) {

  			case no:
  				break;
  			case mod:

  				if (cs->def[def].tri == yes) {

  					conf_warning("%s creates inconsistent choice state", sym->name);

  					cs->flags &= ~def_flags;

  				}

  				break;
  			case yes:

  				if (cs->def[def].tri != no)
  					conf_warning("override: %s changes choice state", sym->name);
  				cs->def[def].val = sym;

  				break;
  			}

  			cs->def[def].tri = EXPR_OR(cs->def[def].tri, sym->def[def].tri);

  		}
  	}

  	free(line);

  	fclose(in);
  
  	if (modules_sym)
  		sym_calc_value(modules_sym);

  	return 0;
  }
  
  int conf_read(const char *name)
  {

  	struct symbol *sym;
  	int i;

  	sym_set_change_count(0);

  	if (conf_read_simple(name, S_DEF_USER))

  		return 1;

  	for_all_symbols(i, sym) {
  		sym_calc_value(sym);

  		if (sym_is_choice(sym) || (sym->flags & SYMBOL_AUTO))

  			continue;

  		if (sym_has_value(sym) && (sym->flags & SYMBOL_WRITE)) {
  			/* check that calculated value agrees with saved value */
  			switch (sym->type) {
  			case S_BOOLEAN:
  			case S_TRISTATE:

  				if (sym->def[S_DEF_USER].tri != sym_get_tristate_value(sym))

  					break;
  				if (!sym_is_choice(sym))

  					continue;

  				/* fall through */

  			default:

  				if (!strcmp(sym->curr.val, sym->def[S_DEF_USER].val))

  					continue;

  				break;
  			}
  		} else if (!sym_has_value(sym) && !(sym->flags & SYMBOL_WRITE))
  			/* no previous value and not saved */

  			continue;

  		conf_unsaved++;
  		/* maybe print value in verbose mode... */

  	}
  
  	for_all_symbols(i, sym) {

  		if (sym_has_value(sym) && !sym_is_choice_value(sym)) {

  			/* Reset values of generates values, so they'll appear
  			 * as new, if they should become visible, but that
  			 * doesn't quite work if the Kconfig and the saved
  			 * configuration disagree.
  			 */
  			if (sym->visible == no && !conf_unsaved)

  				sym->flags &= ~SYMBOL_DEF_USER;

  			switch (sym->type) {
  			case S_STRING:
  			case S_INT:
  			case S_HEX:

  				/* Reset a string value if it's out of range */
  				if (sym_string_within_range(sym, sym->def[S_DEF_USER].val))
  					break;
  				sym->flags &= ~(SYMBOL_VALID|SYMBOL_DEF_USER);
  				conf_unsaved++;
  				break;

  			default:
  				break;
  			}
  		}

  	}

  	sym_add_change_count(conf_warnings || conf_unsaved);

  
  	return 0;
  }

  /*
   * Kconfig configuration printer
   *
   * This printer is used when generating the resulting configuration after
   * kconfig invocation and `defconfig' files. Unset symbol might be omitted by
   * passing a non-NULL argument to the printer.
   *
   */
  static void
  kconfig_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
  {
  
  	switch (sym->type) {
  	case S_BOOLEAN:
  	case S_TRISTATE:
  		if (*value == 'n') {
  			bool skip_unset = (arg != NULL);
  
  			if (!skip_unset)
  				fprintf(fp, "# %s%s is not set
  ",
  				    CONFIG_, sym->name);
  			return;
  		}
  		break;
  	default:
  		break;
  	}
  
  	fprintf(fp, "%s%s=%s
  ", CONFIG_, sym->name, value);
  }
  
  static void
  kconfig_print_comment(FILE *fp, const char *value, void *arg)

  {

  	const char *p = value;
  	size_t l;
  
  	for (;;) {
  		l = strcspn(p, "
  ");
  		fprintf(fp, "#");

  		if (l) {

  			fprintf(fp, " ");

  			xfwrite(p, l, 1, fp);

  			p += l;

  		}

  		fprintf(fp, "
  ");
  		if (*p++ == '\0')

  			break;

  	}

  }

  static struct conf_printer kconfig_printer_cb =

  {

  	.print_symbol = kconfig_print_symbol,
  	.print_comment = kconfig_print_comment,
  };
  
  /*
   * Header printer
   *
   * This printer is used when generating the `include/generated/autoconf.h' file.
   */
  static void
  header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
  {

  	switch (sym->type) {

  	case S_BOOLEAN:

  	case S_TRISTATE: {
  		const char *suffix = "";

  		switch (*value) {
  		case 'n':

  			break;

  		case 'm':
  			suffix = "_MODULE";

  			/* fall through */

  		default:

  			fprintf(fp, "#define %s%s%s 1
  ",
  			    CONFIG_, sym->name, suffix);

  		}

  		break;
  	}
  	case S_HEX: {
  		const char *prefix = "";
  
  		if (value[0] != '0' || (value[1] != 'x' && value[1] != 'X'))
  			prefix = "0x";
  		fprintf(fp, "#define %s%s %s%s
  ",
  		    CONFIG_, sym->name, prefix, value);
  		break;
  	}
  	case S_STRING:
  	case S_INT:
  		fprintf(fp, "#define %s%s %s
  ",
  		    CONFIG_, sym->name, value);

  		break;

  	default:

  		break;

  	}

  }
  
  static void
  header_print_comment(FILE *fp, const char *value, void *arg)
  {
  	const char *p = value;
  	size_t l;
  
  	fprintf(fp, "/*
  ");
  	for (;;) {
  		l = strcspn(p, "
  ");
  		fprintf(fp, " *");
  		if (l) {
  			fprintf(fp, " ");

  			xfwrite(p, l, 1, fp);

  			p += l;
  		}
  		fprintf(fp, "
  ");
  		if (*p++ == '\0')
  			break;
  	}
  	fprintf(fp, " */
  ");
  }
  
  static struct conf_printer header_printer_cb =
  {
  	.print_symbol = header_print_symbol,
  	.print_comment = header_print_comment,
  };
  
  /*

   * Tristate printer
   *
   * This printer is used when generating the `include/config/tristate.conf' file.
   */
  static void
  tristate_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
  {
  
  	if (sym->type == S_TRISTATE && *value != 'n')
  		fprintf(fp, "%s%s=%c
  ", CONFIG_, sym->name, (char)toupper(*value));
  }
  
  static struct conf_printer tristate_printer_cb =
  {
  	.print_symbol = tristate_print_symbol,
  	.print_comment = kconfig_print_comment,
  };
  
  static void conf_write_symbol(FILE *fp, struct symbol *sym,
  			      struct conf_printer *printer, void *printer_arg)
  {
  	const char *str;
  
  	switch (sym->type) {

  	case S_OTHER:
  	case S_UNKNOWN:
  		break;

  	case S_STRING:
  		str = sym_get_string_value(sym);
  		str = sym_escape_string_value(str);
  		printer->print_symbol(fp, sym, str, printer_arg);
  		free((void *)str);
  		break;
  	default:
  		str = sym_get_string_value(sym);
  		printer->print_symbol(fp, sym, str, printer_arg);

  	}
  }

  static void
  conf_write_heading(FILE *fp, struct conf_printer *printer, void *printer_arg)
  {
  	char buf[256];
  
  	snprintf(buf, sizeof(buf),
  	    "
  "
  	    "Automatically generated file; DO NOT EDIT.
  "
  	    "%s
  ",
  	    rootmenu.prompt->text);
  
  	printer->print_comment(fp, buf, printer_arg);
  }

  /*
   * Write out a minimal config.
   * All values that has default values are skipped as this is redundant.
   */
  int conf_write_defconfig(const char *filename)
  {
  	struct symbol *sym;
  	struct menu *menu;
  	FILE *out;
  
  	out = fopen(filename, "w");
  	if (!out)
  		return 1;
  
  	sym_clear_all_valid();
  
  	/* Traverse all menus to find all relevant symbols */
  	menu = rootmenu.list;
  
  	while (menu != NULL)
  	{
  		sym = menu->sym;
  		if (sym == NULL) {
  			if (!menu_is_visible(menu))
  				goto next_menu;
  		} else if (!sym_is_choice(sym)) {
  			sym_calc_value(sym);
  			if (!(sym->flags & SYMBOL_WRITE))
  				goto next_menu;
  			sym->flags &= ~SYMBOL_WRITE;
  			/* If we cannot change the symbol - skip */
  			if (!sym_is_changable(sym))
  				goto next_menu;
  			/* If symbol equals to default value - skip */
  			if (strcmp(sym_get_string_value(sym), sym_get_string_default(sym)) == 0)
  				goto next_menu;
  
  			/*
  			 * If symbol is a choice value and equals to the
  			 * default for a choice - skip.

  			 * But only if value is bool and equal to "y" and
  			 * choice is not "optional".
  			 * (If choice is "optional" then all values can be "n")

  			 */
  			if (sym_is_choice_value(sym)) {
  				struct symbol *cs;
  				struct symbol *ds;
  
  				cs = prop_get_symbol(sym_get_choice_prop(sym));
  				ds = sym_choice_default(cs);

  				if (!sym_is_optional(cs) && sym == ds) {

  					if ((sym->type == S_BOOLEAN) &&
  					    sym_get_tristate_value(sym) == yes)

  						goto next_menu;
  				}
  			}

  			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);

  		}
  next_menu:
  		if (menu->list != NULL) {
  			menu = menu->list;
  		}
  		else if (menu->next != NULL) {
  			menu = menu->next;
  		} else {
  			while ((menu = menu->parent)) {
  				if (menu->next != NULL) {
  					menu = menu->next;
  					break;
  				}
  			}
  		}
  	}
  	fclose(out);
  	return 0;
  }

  int conf_write(const char *name)
  {

  	FILE *out;

  	struct symbol *sym;
  	struct menu *menu;
  	const char *basename;

  	const char *str;

  	char dirname[PATH_MAX+1], tmpname[PATH_MAX+1], newname[PATH_MAX+1];

  	char *env;
  
  	dirname[0] = 0;
  	if (name && name[0]) {
  		struct stat st;
  		char *slash;
  
  		if (!stat(name, &st) && S_ISDIR(st.st_mode)) {
  			strcpy(dirname, name);
  			strcat(dirname, "/");

  			basename = conf_get_configname();

  		} else if ((slash = strrchr(name, '/'))) {
  			int size = slash - name + 1;
  			memcpy(dirname, name, size);
  			dirname[size] = 0;
  			if (slash[1])
  				basename = slash + 1;
  			else

  				basename = conf_get_configname();

  		} else
  			basename = name;
  	} else

  		basename = conf_get_configname();

  	sprintf(newname, "%s%s", dirname, basename);
  	env = getenv("KCONFIG_OVERWRITECONFIG");
  	if (!env || !*env) {
  		sprintf(tmpname, "%s.tmpconfig.%d", dirname, (int)getpid());
  		out = fopen(tmpname, "w");
  	} else {
  		*tmpname = 0;
  		out = fopen(newname, "w");
  	}

  	if (!out)
  		return 1;

  	conf_write_heading(out, &kconfig_printer_cb, NULL);

  	if (!conf_get_changed())

  		sym_clear_all_valid();
  
  	menu = rootmenu.list;
  	while (menu) {
  		sym = menu->sym;
  		if (!sym) {
  			if (!menu_is_visible(menu))
  				goto next;
  			str = menu_get_prompt(menu);
  			fprintf(out, "
  "
  				     "#
  "
  				     "# %s
  "
  				     "#
  ", str);

  		} else if (!(sym->flags & SYMBOL_CHOICE)) {
  			sym_calc_value(sym);
  			if (!(sym->flags & SYMBOL_WRITE))
  				goto next;
  			sym->flags &= ~SYMBOL_WRITE;

  
  			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);

  		}

  next:

  		if (menu->list) {
  			menu = menu->list;
  			continue;
  		}
  		if (menu->next)
  			menu = menu->next;
  		else while ((menu = menu->parent)) {
  			if (menu->next) {
  				menu = menu->next;
  				break;
  			}
  		}
  	}
  	fclose(out);

  
  	if (*tmpname) {

  		strcat(dirname, basename);

  		strcat(dirname, ".old");
  		rename(newname, dirname);
  		if (rename(tmpname, newname))
  			return 1;

  	}

  	conf_message(_("configuration written to %s"), newname);

  	sym_set_change_count(0);

  
  	return 0;
  }

  static int conf_split_config(void)

  {

  	const char *name;

  	char path[PATH_MAX+1];

  	char *s, *d, c;
  	struct symbol *sym;
  	struct stat sb;
  	int res, i, fd;

  	name = conf_get_autoconfig_name();

  	conf_read_simple(name, S_DEF_AUTO);
  
  	if (chdir("include/config"))
  		return 1;
  
  	res = 0;
  	for_all_symbols(i, sym) {
  		sym_calc_value(sym);
  		if ((sym->flags & SYMBOL_AUTO) || !sym->name)
  			continue;
  		if (sym->flags & SYMBOL_WRITE) {
  			if (sym->flags & SYMBOL_DEF_AUTO) {
  				/*
  				 * symbol has old and new value,
  				 * so compare them...
  				 */
  				switch (sym->type) {
  				case S_BOOLEAN:
  				case S_TRISTATE:
  					if (sym_get_tristate_value(sym) ==
  					    sym->def[S_DEF_AUTO].tri)
  						continue;
  					break;
  				case S_STRING:
  				case S_HEX:
  				case S_INT:
  					if (!strcmp(sym_get_string_value(sym),
  						    sym->def[S_DEF_AUTO].val))
  						continue;
  					break;
  				default:
  					break;
  				}
  			} else {
  				/*
  				 * If there is no old value, only 'no' (unset)
  				 * is allowed as new value.
  				 */
  				switch (sym->type) {
  				case S_BOOLEAN:
  				case S_TRISTATE:
  					if (sym_get_tristate_value(sym) == no)
  						continue;
  					break;
  				default:
  					break;
  				}
  			}
  		} else if (!(sym->flags & SYMBOL_DEF_AUTO))
  			/* There is neither an old nor a new value. */
  			continue;
  		/* else
  		 *	There is an old value, but no new value ('no' (unset)
  		 *	isn't saved in auto.conf, so the old value is always
  		 *	different from 'no').
  		 */
  
  		/* Replace all '_' and append ".h" */
  		s = sym->name;
  		d = path;
  		while ((c = *s++)) {
  			c = tolower(c);
  			*d++ = (c == '_') ? '/' : c;
  		}
  		strcpy(d, ".h");
  
  		/* Assume directory path already exists. */
  		fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
  		if (fd == -1) {
  			if (errno != ENOENT) {
  				res = 1;
  				break;
  			}
  			/*
  			 * Create directory components,
  			 * unless they exist already.
  			 */
  			d = path;
  			while ((d = strchr(d, '/'))) {
  				*d = 0;
  				if (stat(path, &sb) && mkdir(path, 0755)) {
  					res = 1;
  					goto out;
  				}
  				*d++ = '/';
  			}
  			/* Try it again. */
  			fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
  			if (fd == -1) {
  				res = 1;
  				break;
  			}
  		}
  		close(fd);
  	}
  out:
  	if (chdir("../.."))
  		return 1;
  
  	return res;
  }

  int conf_write_autoconf(void)
  {
  	struct symbol *sym;

  	const char *name;

  	FILE *out, *tristate, *out_h;

  	int i;

  	sym_clear_all_valid();

  	file_write_dep("include/config/auto.conf.cmd");

  	if (conf_split_config())
  		return 1;

  	out = fopen(".tmpconfig", "w");
  	if (!out)
  		return 1;

  	tristate = fopen(".tmpconfig_tristate", "w");
  	if (!tristate) {
  		fclose(out);
  		return 1;
  	}

  	out_h = fopen(".tmpconfig.h", "w");
  	if (!out_h) {
  		fclose(out);

  		fclose(tristate);

  		return 1;
  	}

  	conf_write_heading(out, &kconfig_printer_cb, NULL);
  
  	conf_write_heading(tristate, &tristate_printer_cb, NULL);
  
  	conf_write_heading(out_h, &header_printer_cb, NULL);

  	for_all_symbols(i, sym) {
  		sym_calc_value(sym);

  		if (!(sym->flags & SYMBOL_WRITE) || !sym->name)

  			continue;

  		/* write symbol to auto.conf, tristate and header files */

  		conf_write_symbol(out, sym, &kconfig_printer_cb, (void *)1);

  		conf_write_symbol(tristate, sym, &tristate_printer_cb, (void *)1);
  
  		conf_write_symbol(out_h, sym, &header_printer_cb, NULL);

  	}
  	fclose(out);

  	fclose(tristate);

  	fclose(out_h);
  
  	name = getenv("KCONFIG_AUTOHEADER");
  	if (!name)

  		name = "include/generated/autoconf.h";

  	if (rename(".tmpconfig.h", name))
  		return 1;

  	name = getenv("KCONFIG_TRISTATE");
  	if (!name)
  		name = "include/config/tristate.conf";
  	if (rename(".tmpconfig_tristate", name))
  		return 1;

  	name = conf_get_autoconfig_name();

  	/*
  	 * This must be the last step, kbuild has a dependency on auto.conf
  	 * and this marks the successful completion of the previous steps.
  	 */
  	if (rename(".tmpconfig", name))
  		return 1;
  
  	return 0;
  }

  static int sym_change_count;

  static void (*conf_changed_callback)(void);

  
  void sym_set_change_count(int count)
  {

  	int _sym_change_count = sym_change_count;

  	sym_change_count = count;

  	if (conf_changed_callback &&
  	    (bool)_sym_change_count != (bool)count)
  		conf_changed_callback();

  }
  
  void sym_add_change_count(int count)
  {

  	sym_set_change_count(count + sym_change_count);

  }

  bool conf_get_changed(void)
  {
  	return sym_change_count;
  }

  
  void conf_set_changed_callback(void (*fn)(void))
  {
  	conf_changed_callback = fn;
  }

  static bool randomize_choice_values(struct symbol *csym)

  {
  	struct property *prop;
  	struct symbol *sym;
  	struct expr *e;
  	int cnt, def;

  	/*

  	 * If choice is mod then we may have more items selected

  	 * and if no then no-one.
  	 * In both cases stop.
  	 */
  	if (csym->curr.tri != yes)

  		return false;

  
  	prop = sym_get_choice_prop(csym);
  
  	/* count entries in choice block */
  	cnt = 0;
  	expr_list_for_each_sym(prop->expr, e, sym)
  		cnt++;
  
  	/*
  	 * find a random value and set it to yes,
  	 * set the rest to no so we have only one set
  	 */
  	def = (rand() % cnt);
  
  	cnt = 0;
  	expr_list_for_each_sym(prop->expr, e, sym) {
  		if (def == cnt++) {
  			sym->def[S_DEF_USER].tri = yes;
  			csym->def[S_DEF_USER].val = sym;
  		}
  		else {
  			sym->def[S_DEF_USER].tri = no;
  		}

  		sym->flags |= SYMBOL_DEF_USER;
  		/* clear VALID to get value calculated */
  		sym->flags &= ~SYMBOL_VALID;

  	}
  	csym->flags |= SYMBOL_DEF_USER;
  	/* clear VALID to get value calculated */
  	csym->flags &= ~(SYMBOL_VALID);

  
  	return true;

  }

  void set_all_choice_values(struct symbol *csym)

  {

  	struct property *prop;

  	struct symbol *sym;

  	struct expr *e;

  
  	prop = sym_get_choice_prop(csym);
  
  	/*
  	 * Set all non-assinged choice values to no
  	 */
  	expr_list_for_each_sym(prop->expr, e, sym) {
  		if (!sym_has_value(sym))
  			sym->def[S_DEF_USER].tri = no;
  	}
  	csym->flags |= SYMBOL_DEF_USER;
  	/* clear VALID to get value calculated */

  	csym->flags &= ~(SYMBOL_VALID | SYMBOL_NEED_SET_CHOICE_VALUES);

  }

  bool conf_set_all_new_symbols(enum conf_def_mode mode)

  {
  	struct symbol *sym, *csym;

  	int i, cnt, pby, pty, ptm;	/* pby: probability of boolean  = y
  					 * pty: probability of tristate = y
  					 * ptm: probability of tristate = m
  					 */
  
  	pby = 50; pty = ptm = 33; /* can't go as the default in switch-case
  				   * below, otherwise gcc whines about
  				   * -Wmaybe-uninitialized */
  	if (mode == def_random) {
  		int n, p[3];
  		char *env = getenv("KCONFIG_PROBABILITY");
  		n = 0;
  		while( env && *env ) {
  			char *endp;
  			int tmp = strtol( env, &endp, 10 );
  			if( tmp >= 0 && tmp <= 100 ) {
  				p[n++] = tmp;
  			} else {
  				errno = ERANGE;
  				perror( "KCONFIG_PROBABILITY" );
  				exit( 1 );
  			}
  			env = (*endp == ':') ? endp+1 : endp;
  			if( n >=3 ) {
  				break;
  			}
  		}
  		switch( n ) {
  		case 1:
  			pby = p[0]; ptm = pby/2; pty = pby-ptm;
  			break;
  		case 2:
  			pty = p[0]; ptm = p[1]; pby = pty + ptm;
  			break;
  		case 3:
  			pby = p[0]; pty = p[1]; ptm = p[2];
  			break;
  		}
  
  		if( pty+ptm > 100 ) {
  			errno = ERANGE;
  			perror( "KCONFIG_PROBABILITY" );
  			exit( 1 );
  		}
  	}

  	bool has_changed = false;

  
  	for_all_symbols(i, sym) {

  		if (sym_has_value(sym) || (sym->flags & SYMBOL_VALID))

  			continue;
  		switch (sym_get_type(sym)) {
  		case S_BOOLEAN:
  		case S_TRISTATE:

  			has_changed = true;

  			switch (mode) {
  			case def_yes:
  				sym->def[S_DEF_USER].tri = yes;
  				break;
  			case def_mod:
  				sym->def[S_DEF_USER].tri = mod;
  				break;
  			case def_no:

  				if (sym->flags & SYMBOL_ALLNOCONFIG_Y)
  					sym->def[S_DEF_USER].tri = yes;
  				else
  					sym->def[S_DEF_USER].tri = no;

  				break;
  			case def_random:

  				sym->def[S_DEF_USER].tri = no;
  				cnt = rand() % 100;
  				if (sym->type == S_TRISTATE) {
  					if (cnt < pty)
  						sym->def[S_DEF_USER].tri = yes;
  					else if (cnt < (pty+ptm))
  						sym->def[S_DEF_USER].tri = mod;
  				} else if (cnt < pby)
  					sym->def[S_DEF_USER].tri = yes;

  				break;
  			default:
  				continue;
  			}

  			if (!(sym_is_choice(sym) && mode == def_random))

  				sym->flags |= SYMBOL_DEF_USER;
  			break;
  		default:
  			break;
  		}
  
  	}

  	sym_clear_all_valid();

  	/*
  	 * We have different type of choice blocks.

  	 * If curr.tri equals to mod then we can select several

  	 * choice symbols in one block.
  	 * In this case we do nothing.

  	 * If curr.tri equals yes then only one symbol can be

  	 * selected in a choice block and we set it to yes,
  	 * and the rest to no.
  	 */

  	if (mode != def_random) {
  		for_all_symbols(i, csym) {
  			if ((sym_is_choice(csym) && !sym_has_value(csym)) ||
  			    sym_is_choice_value(csym))
  				csym->flags |= SYMBOL_NEED_SET_CHOICE_VALUES;
  		}
  	}

  	for_all_symbols(i, csym) {
  		if (sym_has_value(csym) || !sym_is_choice(csym))
  			continue;
  
  		sym_calc_value(csym);

  		if (mode == def_random)

  			has_changed = randomize_choice_values(csym);
  		else {
  			set_all_choice_values(csym);
  			has_changed = true;
  		}

  	}

  
  	return has_changed;

  }