kconfig: Add error handling to KCONFIG_ALLCONFIG

- Only try to read the file specified if KCONFIG_ALL_CONFIG is set to
  something other than the empty string or "1".

- Don't use stat to check the name passed to conf_read_simple so that
  zconf_fopen can find the file in the current directory or in SRCTREE
  removing a extremely source of confusing failure, where KCONFIG_ALL_CONFIG
  was not interpreted with respect to the directory make was called in.

- If conf_read_simple fails complain clearly and stop processing.
  Allowing the simple debugging of typos.

- Clearly document the behavior so it is clear to users which
  values are treated as flags and which values are treated as
  filenames.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

1 files changed, 14 insertions, 6 deletions

diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index f208f900ed3a..0fdda9169308 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -574,8 +574,13 @@ int main(int ac, char **av)
 	case alldefconfig:
 	case randconfig:
 		name = getenv("KCONFIG_ALLCONFIG");
-		if (name && !stat(name, &tmpstat)) {
-			conf_read_simple(name, S_DEF_USER);
+		if (name && (strcmp(name, "") != 0) && (strcmp(name, "1") != 0)) {
+			if (conf_read_simple(name, S_DEF_USER)) {
+				fprintf(stderr,
+					_("*** Can't read seed configuration \"%s\"!\n"),
+					name);
+				exit(1);
+			}
 			break;
 		}
 		switch (input_mode) {
@@ -586,10 +591,13 @@ int main(int ac, char **av)
 		case randconfig:	name = "allrandom.config"; break;
 		default: break;
 		}
-		if (!stat(name, &tmpstat))
-			conf_read_simple(name, S_DEF_USER);
-		else if (!stat("all.config", &tmpstat))
-			conf_read_simple("all.config", S_DEF_USER);
+		if (conf_read_simple(name, S_DEF_USER) &&
+		    conf_read_simple("all.config", S_DEF_USER)) {
+			fprintf(stderr,
+				_("*** KCONFIG_ALLCONFIG set, but no \"%s\" or \"all.config\" file found\n"),
+				name);
+			exit(1);
+		}
 		break;
 	default:
 		break;