[PATCH] kconfig: preset config during all*config

Allow to force setting of config variables during all{no,mod,yes,random}config
to a specific value.  For that conf first checks the KCONFIG_ALLCONFIG
environment variable for a file name, otherwise it checks for
all{no,mod,yes,random}.config and all.config.  The file is a normal config
file, which presets the config variables, but they are still subject to normal
dependency checks.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index dffbf2e..8ba5d29 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -82,6 +82,15 @@
 	}
 
 	switch (input_mode) {
+	case set_no:
+	case set_mod:
+	case set_yes:
+	case set_random:
+		if (sym_has_value(sym)) {
+			printf("%s\n", def);
+			return;
+		}
+		break;
 	case ask_new:
 	case ask_silent:
 		if (sym_has_value(sym)) {
@@ -558,6 +567,27 @@
 	case ask_new:
 		conf_read(NULL);
 		break;
+	case set_no:
+	case set_mod:
+	case set_yes:
+	case set_random:
+		name = getenv("KCONFIG_ALLCONFIG");
+		if (name && !stat(name, &tmpstat)) {
+			conf_read_simple(name);
+			break;
+		}
+		switch (input_mode) {
+		case set_no:	 name = "allno.config"; break;
+		case set_mod:	 name = "allmod.config"; break;
+		case set_yes:	 name = "allyes.config"; break;
+		case set_random: name = "allrandom.config"; break;
+		default: break;
+		}
+		if (!stat(name, &tmpstat))
+			conf_read_simple(name);
+		else if (!stat("all.config", &tmpstat))
+			conf_read_simple("all.config");
+		break;
 	default:
 		break;
 	}