Properly create output for config file

Signed-off-by: Evan Lezar <elezar@nvidia.com>

cmd/nvidia-ctk/config/config.go

@@ -19,7 +19,6 @@ package config
 import (
 	"errors"
 	"fmt"
-	"os"
 	"strconv"
 	"strings"
 
@@ -111,7 +110,19 @@ func run(c *cli.Context, opts *options) error {
 		cfgToml.Set(key, value)
 	}
 
-	cfgToml.Save(os.Stdout)
+	if err := opts.EnsureOutputFolder(); err != nil {
+		return fmt.Errorf("failed to create output directory: %v", err)
+	}
+	output, err := opts.CreateOutput()
+	if err != nil {
+		return fmt.Errorf("failed to open output file: %v", err)
+	}
+	defer output.Close()
+
+	if err != nil {
+		return err
+	}
+	cfgToml.Save(output)
 	return nil
 }
 

cmd/nvidia-ctk/config/flags/options.go

@@ -39,13 +39,23 @@ func (o Options) Validate() error {
 	return nil
 }
 
+// GetOutput returns the effective output
+func (o Options) GetOutput() string {
+	if o.InPlace {
+		return o.Config
+	}
+
+	return o.Output
+}
+
 // EnsureOutputFolder creates the output folder if it does not exist.
 // If the output folder is not specified (i.e. output to STDOUT), it is ignored.
 func (o Options) EnsureOutputFolder() error {
-	if o.Output == "" {
+	output := o.GetOutput()
+	if output == "" {
 		return nil
 	}
-	if dir := filepath.Dir(o.Output); dir != "" {
+	if dir := filepath.Dir(output); dir != "" {
 		return os.MkdirAll(dir, 0755)
 	}
 	return nil
@@ -53,11 +63,12 @@ func (o Options) EnsureOutputFolder() error {
 
 // CreateOutput creates the writer for the output.
 func (o Options) CreateOutput() (io.WriteCloser, error) {
-	if o.Output != "" {
-		return os.Create(o.Output)
+	output := o.GetOutput()
+	if output == "" {
+		return nullCloser{os.Stdout}, nil
 	}
 
-	return nullCloser{os.Stdout}, nil
+	return os.Create(output)
 }
 
 // nullCloser is a writer that does nothing on Close.