treewide: add non-zero exit codes in more places

Author: malt3

src/cmd/compress/compress.go

@@ -76,6 +76,7 @@ func CompressProcess(ctx context.Context, args []string) {
 	}
 	if openErr != nil {
 		fmt.Fprintf(os.Stderr, "Error opening output layer: %v\n", openErr)
+		os.Exit(1)
 	}
 
 	var outputFormat api.LayerFormat

src/cmd/layer/layer.go

@@ -233,6 +233,7 @@ func handleLayerState(
 	defer func() {
 		if err := tw.Close(); err != nil {
 			fmt.Fprintf(os.Stderr, "Error closing tar writer: %v\n", err)
+			os.Exit(1)
 		}
 	}()
 	if err := tw.Import(casImporter); err != nil {

src/cmd/push/push.go

@@ -46,8 +46,9 @@ func DeployDispatch(ctx context.Context, rawRequest []byte) {
 	// Parse os.Args, skipping the program name
 	if len(os.Args) > 1 {
 		if err := fs.Parse(os.Args[1:]); err != nil {
-			// Continue with no additional flags if parsing fails
-			fmt.Fprintf(os.Stderr, "Warning: failed to parse flags: %v\n", err)
+			fmt.Fprintf(os.Stderr, "Error: failed to parse flags: %v\n", err)
+			fs.Usage()
+			os.Exit(1)
 		}
 	}
 

src/cmd/registry/registry.go

@@ -201,7 +201,9 @@ func Run(ctx context.Context, args []string) {
 		Protocols:         protos,
 	}
 	fmt.Fprintf(os.Stderr, "Listening on %d\n", porti)
-	server.Serve(listener)
+	if err := server.Serve(listener); err != nil && err != http.ErrServerClosed {
+		log.Fatalf("Failed to serve HTTP server: %v", err)
+	}
 }
 
 func main() {