pull latest kconfig from kernel

1 files changed, 464 insertions, 138 deletions

diff --git a/extra/config/confdata.c b/extra/config/confdata.c
index 60bfe77c4..0dbd14152 100644
--- a/extra/config/confdata.c
+++ b/extra/config/confdata.c
@@ -5,6 +5,7 @@
 
 #include <sys/stat.h>
 #include <ctype.h>
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -14,15 +15,31 @@
 #define LKC_DIRECT_LINK
 #include "lkc.h"
 
-const char conf_def_filename[] = ".config";
+static void conf_warning(const char *fmt, ...)
+	__attribute__ ((format (printf, 1, 2)));
 
-const char conf_defname[] = "extra/Configs/Config.default";
+static const char *conf_filename;
+static int conf_lineno, conf_warnings, conf_unsaved;
 
-const char *conf_confnames[] = {
-	".config",
-	conf_defname,
-	NULL,
-};
+const char conf_defname[] = "extra/Configs/defconfigs/$ARCH";
+
+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, "\n");
+	va_end(ap);
+	conf_warnings++;
+}
+
+const char *conf_get_configname(void)
+{
+	char *name = getenv("KCONFIG_CONFIG");
+
+	return name ? name : ".config";
+}
 
 static char *conf_expand_value(const char *in)
 {
@@ -66,53 +83,70 @@ char *conf_get_default_confname(void)
 	return name;
 }
 
-int conf_read(const char *name)
+int conf_read_simple(const char *name, int def)
 {
 	FILE *in = NULL;
 	char line[1024];
 	char *p, *p2;
-	int lineno = 0;
 	struct symbol *sym;
-	struct property *prop;
-	struct expr *e;
-	int i;
+	int i, def_flags;
 
 	if (name) {
 		in = zconf_fopen(name);
 	} else {
-		const char **names = conf_confnames;
-		while ((name = *names++)) {
-			name = conf_expand_value(name);
+		struct property *prop;
+
+		name = conf_get_configname();
+		in = zconf_fopen(name);
+		if (in)
+			goto load;
+		sym_add_change_count(1);
+		if (!sym_defconfig_list)
+			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) {
 				printf(_("#\n"
-				         "# using defaults found in %s\n"
-				         "#\n"), name);
-				break;
+					 "# using defaults found in %s\n"
+					 "#\n"), 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_NEW | SYMBOL_CHANGED;
-		sym->flags &= ~SYMBOL_VALID;
+		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->user.val)
-				free(sym->user.val);
+			if (sym->def[def].val)
+				free(sym->def[def].val);
 		default:
-			sym->user.val = NULL;
-			sym->user.tri = no;
+			sym->def[def].val = NULL;
+			sym->def[def].tri = no;
 		}
 	}
 
 	while (fgets(line, sizeof(line), in)) {
-		lineno++;
+		conf_lineno++;
 		sym = NULL;
 		switch (line[0]) {
 		case '#':
@@ -124,54 +158,84 @@ int conf_read(const char *name)
 			*p++ = 0;
 			if (strncmp(p, "is not set", 10))
 				continue;
-			sym = sym_find(line + 2);
-			if (!sym) {
-				fprintf(stderr, "%s:%d: trying to assign nonexistent symbol %s\n", name, lineno, line + 2);
+			if (def == S_DEF_USER) {
+				sym = sym_find(line + 2);
+				if (!sym) {
+					conf_warning("trying to assign nonexistent symbol %s", line + 2);
+					break;
+				}
+			} else {
+				sym = sym_lookup(line + 2, 0);
+				if (sym->type == S_UNKNOWN)
+					sym->type = S_BOOLEAN;
+			}
+			if (sym->flags & def_flags) {
+				conf_warning("trying to reassign symbol %s", sym->name);
 				break;
 			}
 			switch (sym->type) {
 			case S_BOOLEAN:
 			case S_TRISTATE:
-				sym->user.tri = no;
-				sym->flags &= ~SYMBOL_NEW;
+				sym->def[def].tri = no;
+				sym->flags |= def_flags;
 				break;
 			default:
 				;
 			}
 			break;
-
 		case 'A' ... 'Z':
 			p = strchr(line, '=');
 			if (!p)
 				continue;
 			*p++ = 0;
 			p2 = strchr(p, '\n');
-			if (p2)
-				*p2 = 0;
-			sym = sym_find(line);
-			if (!sym) {
-				fprintf(stderr, "%s:%d: trying to assign nonexistent symbol %s\n", name, lineno, line);
+			if (p2) {
+				*p2-- = 0;
+				if (*p2 == '\r')
+					*p2 = 0;
+			}
+			if (def == S_DEF_USER) {
+				sym = sym_find(line);
+				if (!sym) {
+					conf_warning("trying to assign nonexistent symbol %s", line);
+					break;
+				}
+			} else {
+				sym = sym_lookup(line, 0);
+				if (sym->type == S_UNKNOWN)
+					sym->type = S_OTHER;
+			}
+			if (sym->flags & def_flags) {
+				conf_warning("trying to reassign symbol %s", sym->name);
 				break;
 			}
 			switch (sym->type) {
 			case S_TRISTATE:
 				if (p[0] == 'm') {
-					sym->user.tri = mod;
-					sym->flags &= ~SYMBOL_NEW;
+					sym->def[def].tri = mod;
+					sym->flags |= def_flags;
 					break;
 				}
 			case S_BOOLEAN:
 				if (p[0] == 'y') {
-					sym->user.tri = yes;
-					sym->flags &= ~SYMBOL_NEW;
+					sym->def[def].tri = yes;
+					sym->flags |= def_flags;
 					break;
 				}
 				if (p[0] == 'n') {
-					sym->user.tri = no;
-					sym->flags &= ~SYMBOL_NEW;
+					sym->def[def].tri = no;
+					sym->flags |= def_flags;
 					break;
 				}
+				conf_warning("symbol value '%s' invalid for %s", p, sym->name);
 				break;
+			case S_OTHER:
+				if (*p != '"') {
+					for (p2 = p; *p2 && !isspace(*p2); p2++)
+						;
+					sym->type = S_STRING;
+					goto done;
+				}
 			case S_STRING:
 				if (*p++ != '"')
 					break;
@@ -183,62 +247,105 @@ int conf_read(const char *name)
 					memmove(p2, p2 + 1, strlen(p2));
 				}
 				if (!p2) {
-					fprintf(stderr, "%s:%d: invalid string found\n", name, lineno);
-					exit(1);
+					conf_warning("invalid string found");
+					continue;
 				}
 			case S_INT:
 			case S_HEX:
+			done:
 				if (sym_string_valid(sym, p)) {
-					sym->user.val = strdup(p);
-					sym->flags &= ~SYMBOL_NEW;
+					sym->def[def].val = strdup(p);
+					sym->flags |= def_flags;
 				} else {
-					fprintf(stderr, "%s:%d: symbol value '%s' invalid for %s\n", name, lineno, p, sym->name);
-					exit(1);
+					conf_warning("symbol value '%s' invalid for %s", p, sym->name);
+					continue;
 				}
 				break;
 			default:
 				;
 			}
 			break;
+		case '\r':
 		case '\n':
 			break;
 		default:
+			conf_warning("unexpected data");
 			continue;
 		}
 		if (sym && sym_is_choice_value(sym)) {
 			struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
-			switch (sym->user.tri) {
+			switch (sym->def[def].tri) {
 			case no:
 				break;
 			case mod:
-				if (cs->user.tri == yes)
-					/* warn? */;
+				if (cs->def[def].tri == yes) {
+					conf_warning("%s creates inconsistent choice state", sym->name);
+					cs->flags &= ~def_flags;
+				}
 				break;
 			case yes:
-				if (cs->user.tri != no)
-					/* warn? */;
-				cs->user.val = sym;
+				if (cs->def[def].tri != no) {
+					conf_warning("%s creates inconsistent choice state", sym->name);
+					cs->flags &= ~def_flags;
+				} else
+					cs->def[def].val = sym;
 				break;
 			}
-			cs->user.tri = E_OR(cs->user.tri, sym->user.tri);
-			cs->flags &= ~SYMBOL_NEW;
+			cs->def[def].tri = E_OR(cs->def[def].tri, sym->def[def].tri);
 		}
 	}
 	fclose(in);
 
 	if (modules_sym)
 		sym_calc_value(modules_sym);
+	return 0;
+}
+
+int conf_read(const char *name)
+{
+	struct symbol *sym;
+	struct property *prop;
+	struct expr *e;
+	int i, flags;
+
+	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))
+			goto sym_ok;
+		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))
+					goto sym_ok;
+			default:
+				if (!strcmp(sym->curr.val, sym->def[S_DEF_USER].val))
+					goto sym_ok;
+				break;
+			}
+		} else if (!sym_has_value(sym) && !(sym->flags & SYMBOL_WRITE))
+			/* no previous value and not saved */
+			goto sym_ok;
+		conf_unsaved++;
+		/* maybe print value in verbose mode... */
+	sym_ok:
 		if (sym_has_value(sym) && !sym_is_choice_value(sym)) {
 			if (sym->visible == no)
-				sym->flags |= SYMBOL_NEW;
+				sym->flags &= ~SYMBOL_DEF_USER;
 			switch (sym->type) {
 			case S_STRING:
 			case S_INT:
 			case S_HEX:
-				if (!sym_string_within_range(sym, sym->user.val))
-					sym->flags |= SYMBOL_NEW;
+				if (!sym_string_within_range(sym, sym->def[S_DEF_USER].val))
+					sym->flags &= ~(SYMBOL_VALID|SYMBOL_DEF_USER);
 			default:
 				break;
 			}
@@ -246,19 +353,21 @@ int conf_read(const char *name)
 		if (!sym_is_choice(sym))
 			continue;
 		prop = sym_get_choice_prop(sym);
+		flags = sym->flags;
 		for (e = prop->expr; e; e = e->left.expr)
 			if (e->right.sym->visible != no)
-				sym->flags |= e->right.sym->flags & SYMBOL_NEW;
+				flags &= e->right.sym->flags;
+		sym->flags &= flags | ~SYMBOL_DEF_USER;
 	}
 
-	sym_change_count = 1;
+	sym_add_change_count(conf_warnings || conf_unsaved);
 
 	return 0;
 }
 
 int conf_write(const char *name)
 {
-	FILE *out, *out_h;
+	FILE *out;
 	struct symbol *sym;
 	struct menu *menu;
 	const char *basename;
@@ -277,7 +386,7 @@ int conf_write(const char *name)
 		if (!stat(name, &st) && S_ISDIR(st.st_mode)) {
 			strcpy(dirname, name);
 			strcat(dirname, "/");
-			basename = conf_def_filename;
+			basename = conf_get_configname();
 		} else if ((slash = strrchr(name, '/'))) {
 			int size = slash - name + 1;
 			memcpy(dirname, name, size);
@@ -285,22 +394,26 @@ int conf_write(const char *name)
 			if (slash[1])
 				basename = slash + 1;
 			else
-				basename = conf_def_filename;
+				basename = conf_get_configname();
 		} else
 			basename = name;
 	} else
-		basename = conf_def_filename;
+		basename = conf_get_configname();
 
-	sprintf(newname, "%s.tmpconfig.%d", dirname, (int)getpid());
-	out = fopen(newname, "w");
+	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;
-	out_h = NULL;
-	if (!name) {
-		out_h = fopen(".tmpconfig.h", "w");
-		if (!out_h)
-			return 1;
-	}
+
+	sym = sym_lookup("VERSION", 0);
+	sym_calc_value(sym);
 	time(&now);
 	env = getenv("KCONFIG_NOTIMESTAMP");
 	if (env && *env)
@@ -312,27 +425,8 @@ int conf_write(const char *name)
 		       "#\n"),
 		     use_timestamp ? "# " : "",
 		     use_timestamp ? ctime(&now) : "");
-	if (out_h)
-		fprintf(out_h, "/*\n"
-			       " * Automatically generated C config: don't edit\n"
-			       "%s%s"
-			       " */\n"
-			       "#if !defined __FEATURES_H && !defined __need_uClibc_config_h\n"
-			       "#error Never include <bits/uClibc_config.h> directly; use <features.h> instead\n"
-			       "#endif\n\n"
-			       "/*\n"
-			       " * Version Number\n"
-			       " */\n"
-			       "#define __UCLIBC_MAJOR__ %s\n"
-			       "#define __UCLIBC_MINOR__ %s\n"
-			       "#define __UCLIBC_SUBLEVEL__ %s\n",
-			       use_timestamp ? " * " : "",
-			       use_timestamp ? ctime(&now) : "",
-			       getenv("MAJOR_VERSION"),
-			       getenv("MINOR_VERSION"),
-			       getenv("SUBLEVEL"));
-
-	if (!sym_change_count)
+
+	if (!conf_get_changed())
 		sym_clear_all_valid();
 
 	menu = rootmenu.list;
@@ -346,11 +440,6 @@ int conf_write(const char *name)
 				     "#\n"
 				     "# %s\n"
 				     "#\n", str);
-			if (out_h)
-				fprintf(out_h, "\n"
-					       "/*\n"
-					       " * %s\n"
-					       " */\n", str);
 		} else if (!(sym->flags & SYMBOL_CHOICE)) {
 			sym_calc_value(sym);
 			if (!(sym->flags & SYMBOL_WRITE))
@@ -368,59 +457,39 @@ int conf_write(const char *name)
 				switch (sym_get_tristate_value(sym)) {
 				case no:
 					fprintf(out, "# %s is not set\n", sym->name);
-					if (out_h)
-						fprintf(out_h, "#undef __%s__\n", sym->name);
 					break;
 				case mod:
 					fprintf(out, "%s=m\n", sym->name);
-					if (out_h)
-						fprintf(out_h, "#define %s_MODULE 1\n", sym->name);
 					break;
 				case yes:
 					fprintf(out, "%s=y\n", sym->name);
-					if (out_h)
-						fprintf(out_h, "#define __%s__ 1\n", sym->name);
 					break;
 				}
 				break;
 			case S_STRING:
-				// fix me
 				str = sym_get_string_value(sym);
 				fprintf(out, "%s=\"", sym->name);
-				if (out_h)
-					fprintf(out_h, "#define __%s__ \"", sym->name);
-				do {
+				while (1) {
 					l = strcspn(str, "\"\\");
 					if (l) {
 						fwrite(str, l, 1, out);
-						if (out_h)
-							fwrite(str, l, 1, out_h);
-					}
-					str += l;
-					while (*str == '\\' || *str == '"') {
-						fprintf(out, "\\%c", *str);
-						if (out_h)
-							fprintf(out_h, "\\%c", *str);
-						str++;
+						str += l;
 					}
-				} while (*str);
+					if (!*str)
+						break;
+					fprintf(out, "\\%c", *str++);
+				}
 				fputs("\"\n", out);
-				if (out_h)
-					fputs("\"\n", out_h);
 				break;
 			case S_HEX:
 				str = sym_get_string_value(sym);
 				if (str[0] != '0' || (str[1] != 'x' && str[1] != 'X')) {
 					fprintf(out, "%s=%s\n", sym->name, str);
-					if (out_h)
-						fprintf(out_h, "#define __%s__ 0x%s\n", sym->name, str);
 					break;
 				}
 			case S_INT:
 				str = sym_get_string_value(sym);
 				fprintf(out, "%s=%s\n", sym->name, str);
-				if (out_h)
-					fprintf(out_h, "#define __%s__ %s\n", sym->name, str);
 				break;
 			}
 		}
@@ -440,22 +509,279 @@ int conf_write(const char *name)
 		}
 	}
 	fclose(out);
-	if (out_h) {
-		fclose(out_h);
-		rename(".tmpconfig.h", "include/bits/uClibc_config.h");
-		file_write_dep(NULL);
+
+	if (*tmpname) {
+		strcat(dirname, basename);
+		strcat(dirname, ".old");
+		rename(newname, dirname);
+		if (rename(tmpname, newname))
+			return 1;
 	}
-	if (!name || basename != conf_def_filename) {
-		if (!name)
-			name = conf_def_filename;
-		sprintf(tmpname, "%s.old", name);
-		rename(name, tmpname);
+
+	printf(_("#\n"
+		 "# configuration written to %s\n"
+		 "#\n"), newname);
+
+	sym_set_change_count(0);
+
+	return 0;
+}
+
+int conf_split_config(void)
+{
+	char *name, path[128];
+	char *s, *d, c;
+	struct symbol *sym;
+	struct stat sb;
+	int res, i, fd;
+
+	name = getenv("KCONFIG_AUTOCONFIG");
+	if (!name)
+		name = "include/config/auto.conf";
+	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);
 	}
-	sprintf(tmpname, "%s%s", dirname, basename);
-	if (rename(newname, tmpname))
+out:
+	if (chdir("../.."))
+		return 1;
+
+	return res;
+}
+
+int conf_write_autoconf(void)
+{
+	struct symbol *sym;
+	const char *str;
+	char *name;
+	FILE *out, *out_h;
+	time_t now;
+	int i, l;
+
+	return system("./extra/config/conf-header.sh .config > include/bits/uClibc_config.h");
+
+	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;
 
-	sym_change_count = 0;
+	out_h = fopen(".tmpconfig.h", "w");
+	if (!out_h) {
+		fclose(out);
+		return 1;
+	}
+
+	sym = sym_lookup("VERSION", 0);
+	sym_calc_value(sym);
+	time(&now);
+	fprintf(out, "#\n"
+		     "# Automatically generated make config: don't edit\n"
+		     "# %s"
+		     "#\n",
+		     ctime(&now));
+	fprintf(out_h, "/*\n"
+		       " * Automatically generated C config: don't edit\n"
+		       " * %s"
+		       " */\n",
+		       ctime(&now));
+
+	for_all_symbols(i, sym) {
+		sym_calc_value(sym);
+		if (!(sym->flags & SYMBOL_WRITE) || !sym->name)
+			continue;
+		switch (sym->type) {
+		case S_BOOLEAN:
+		case S_TRISTATE:
+			switch (sym_get_tristate_value(sym)) {
+			case no:
+				break;
+			case mod:
+				fprintf(out, "%s=m\n", sym->name);
+				fprintf(out_h, "#define %s_MODULE 1\n", sym->name);
+				break;
+			case yes:
+				fprintf(out, "%s=y\n", sym->name);
+				fprintf(out_h, "#define %s 1\n", sym->name);
+				break;
+			}
+			break;
+		case S_STRING:
+			str = sym_get_string_value(sym);
+			fprintf(out, "%s=\"", sym->name);
+			fprintf(out_h, "#define %s \"", sym->name);
+			while (1) {
+				l = strcspn(str, "\"\\");
+				if (l) {
+					fwrite(str, l, 1, out);
+					fwrite(str, l, 1, out_h);
+					str += l;
+				}
+				if (!*str)
+					break;
+				fprintf(out, "\\%c", *str);
+				fprintf(out_h, "\\%c", *str);
+				str++;
+			}
+			fputs("\"\n", out);
+			fputs("\"\n", out_h);
+			break;
+		case S_HEX:
+			str = sym_get_string_value(sym);
+			if (str[0] != '0' || (str[1] != 'x' && str[1] != 'X')) {
+				fprintf(out, "%s=%s\n", sym->name, str);
+				fprintf(out_h, "#define %s 0x%s\n", sym->name, str);
+				break;
+			}
+		case S_INT:
+			str = sym_get_string_value(sym);
+			fprintf(out, "%s=%s\n", sym->name, str);
+			fprintf(out_h, "#define %s %s\n", sym->name, str);
+			break;
+		default:
+			break;
+		}
+	}
+	fclose(out);
+	fclose(out_h);
+
+	name = getenv("KCONFIG_AUTOHEADER");
+	if (!name)
+		name = "include/linux/autoconf.h";
+	if (rename(".tmpconfig.h", name))
+		return 1;
+	name = getenv("KCONFIG_AUTOCONFIG");
+	if (!name)
+		name = "include/config/auto.conf";
+	/*
+	 * 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;
+}