cmd/dockerd: remove unused error-returns

getDefaultDaemonConfigDir would never return an error and because of that,
neither would getDefaultDaemonConfigFile, so we can remove these error returns.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cmd/dockerd/daemon_test.go

@@ -19,8 +19,7 @@ func defaultOptions(t *testing.T, configFile string) *daemonOptions {
 	opts.flags = &pflag.FlagSet{}
 	opts.installFlags(opts.flags)
 	installConfigFlags(opts.daemonConfig, opts.flags)
-	defaultDaemonConfigFile, err := getDefaultDaemonConfigFile()
-	assert.NilError(t, err)
+	defaultDaemonConfigFile := getDefaultDaemonConfigFile()
 	opts.flags.StringVar(&opts.configFile, "config-file", defaultDaemonConfigFile, "")
 	opts.configFile = configFile
 	err = opts.flags.Parse([]string{})

cmd/dockerd/daemon_unix.go

@@ -21,26 +21,26 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-func getDefaultDaemonConfigDir() (string, error) {
+func getDefaultDaemonConfigDir() string {
 	if !honorXDG {
-		return "/etc/docker", nil
+		return "/etc/docker"
 	}
 	// NOTE: CLI uses ~/.docker while the daemon uses ~/.config/docker, because
 	// ~/.docker was not designed to store daemon configurations.
 	// In future, the daemon directory may be renamed to ~/.config/moby-engine (?).
 	configHome, err := homedir.GetConfigHome()
 	if err != nil {
-		return "", nil
+		return ""
 	}
-	return filepath.Join(configHome, "docker"), nil
+	return filepath.Join(configHome, "docker")
 }
 
-func getDefaultDaemonConfigFile() (string, error) {
-	dir, err := getDefaultDaemonConfigDir()
-	if err != nil {
-		return "", err
+func getDefaultDaemonConfigFile() string {
+	dir := getDefaultDaemonConfigDir()
+	if dir == "" {
+		return ""
 	}
-	return filepath.Join(dir, "daemon.json"), nil
+	return filepath.Join(dir, "daemon.json")
 }
 
 // setDefaultUmask sets the umask to 0022 to avoid problems

cmd/dockerd/daemon_windows.go

@@ -12,8 +12,8 @@ import (
 	"golang.org/x/sys/windows"
 )
 
-func getDefaultDaemonConfigFile() (string, error) {
-	return "", nil
+func getDefaultDaemonConfigFile() string {
+	return ""
 }
 
 // loadCLIPlatformConfig loads the platform specific CLI configuration

cmd/dockerd/docker.go

@@ -43,11 +43,7 @@ func newDaemonCommand() (*cobra.Command, error) {
 
 	flags := cmd.Flags()
 	flags.BoolP("version", "v", false, "Print version information and quit")
-	defaultDaemonConfigFile, err := getDefaultDaemonConfigFile()
-	if err != nil {
-		return nil, err
-	}
-	flags.StringVar(&opts.configFile, "config-file", defaultDaemonConfigFile, "Daemon configuration file")
+	flags.StringVar(&opts.configFile, "config-file", getDefaultDaemonConfigFile(), "Daemon configuration file")
 	configureCertsDir()
 	opts.installFlags(flags)
 	installConfigFlags(opts.daemonConfig, flags)