Switch uses of os.Getenv that check for empty string to os.LookupEnv.

Whether the variable was found is already returned by syscall.Getenv.
os.Getenv drops this value while os.Lookupenv passes it along.

PiperOrigin-RevId: 351674032

2 files changed, 4 insertions, 5 deletions

diff --git a/runsc/cmd/gofer_test.go b/runsc/cmd/gofer_test.go
index cbea7f127..fea62a4f4 100644
--- a/runsc/cmd/gofer_test.go
+++ b/runsc/cmd/gofer_test.go
@@ -24,11 +24,10 @@ import (
 )
 
 func tmpDir() string {
-	dir := os.Getenv("TEST_TMPDIR")
-	if dir == "" {
-		dir = "/tmp"
+	if dir, ok := os.LookupEnv("TEST_TMPDIR"); ok {
+		return dir
 	}
-	return dir
+	return "/tmp"
 }
 
 type dir struct {
diff --git a/runsc/config/flags.go b/runsc/config/flags.go
index 02ab9255a..7e738dfdf 100644
--- a/runsc/config/flags.go
+++ b/runsc/config/flags.go
@@ -114,7 +114,7 @@ func NewFromFlags() (*Config, error) {
 	if len(conf.RootDir) == 0 {
 		// If not set, set default root dir to something (hopefully) user-writeable.
 		conf.RootDir = "/var/run/runsc"
-		if runtimeDir := os.Getenv("XDG_RUNTIME_DIR"); runtimeDir != "" {
+		if runtimeDir, ok := os.LookupEnv("XDG_RUNTIME_DIR"); ok {
 			conf.RootDir = filepath.Join(runtimeDir, "runsc")
 		}
 	}