quadlet should exit non zero on failures

cmd/quadlet/main.go

@@ -77,8 +77,7 @@ func Logf(format string, a ...interface{}) {
 	s := fmt.Sprintf(format, a...)
 	line := fmt.Sprintf("quadlet-generator[%d]: %s", os.Getpid(), s)
 
-	if !logToKmsg(line) {
-		// If we can't log, print to stderr
+	if !logToKmsg(line) || dryRunFlag {
 		fmt.Fprintf(os.Stderr, "%s\n", line)
 		os.Stderr.Sync()
 	}
@@ -133,13 +132,14 @@ func isExtSupported(filename string) bool {
 	return ok
 }
 
-func loadUnitsFromDir(sourcePath string, units map[string]*parser.UnitFile) {
+func loadUnitsFromDir(sourcePath string, units map[string]*parser.UnitFile) error {
+	var prevError error
 	files, err := os.ReadDir(sourcePath)
 	if err != nil {
 		if !errors.Is(err, os.ErrNotExist) {
-			Logf("Can't read \"%s\": %s", sourcePath, err)
+			return err
 		}
-		return
+		return nil
 	}
 
 	for _, file := range files {
@@ -150,16 +150,20 @@ func loadUnitsFromDir(sourcePath string, units map[string]*parser.UnitFile) {
 			Debugf("Loading source unit file %s", path)
 
 			if f, err := parser.ParseUnitFile(path); err != nil {
-				Logf("Error loading '%s', ignoring: %s", path, err)
+				err = fmt.Errorf("error loading %q, %w", path, err)
+				if prevError != nil {
+					prevError = fmt.Errorf("%s\n%s", prevError, err)
+				}
 			} else {
 				units[name] = f
 			}
 		}
 	}
+	return prevError
 }
 
 func generateServiceFile(service *parser.UnitFile) error {
-	Debugf("writing '%s'", service.Path)
+	Debugf("writing %q", service.Path)
 
 	service.PrependComment("",
 		fmt.Sprintf("Automatically generated by %s", os.Args[0]),
@@ -303,15 +307,24 @@ func warnIfAmbiguousName(container *parser.UnitFile) {
 }
 
 func main() {
-	exitCode := 0
+	if err := process(); err != nil {
+		Logf("%s", err.Error())
+		os.Exit(1)
+	}
+	os.Exit(0)
+}
+
+func process() error {
+	var prevError error
+
 	prgname := path.Base(os.Args[0])
 	isUserFlag = strings.Contains(prgname, "user")
 
 	flag.Parse()
 
 	if versionFlag {
 		fmt.Printf("%s\n", rawversion.RawVersion)
-		return
+		return prevError
 	}
 
 	if verboseFlag || dryRunFlag {
@@ -322,9 +335,16 @@ func main() {
 		noKmsg = true
 	}
 
+	reportError := func(err error) {
+		if prevError != nil {
+			err = fmt.Errorf("%s\n%s", prevError, err)
+		}
+		prevError = err
+	}
+
 	if !dryRunFlag && flag.NArg() < 1 {
-		Logf("Missing output directory argument")
-		os.Exit(1)
+		reportError(errors.New("missing output directory argument"))
+		return prevError
 	}
 
 	var outputPath string
@@ -339,21 +359,23 @@ func main() {
 
 	units := make(map[string]*parser.UnitFile)
 	for _, d := range sourcePaths {
-		loadUnitsFromDir(d, units)
+		if err := loadUnitsFromDir(d, units); err != nil {
+			reportError(err)
+		}
 	}
 
 	if len(units) == 0 {
 		// containers/podman/issues/17374: exit cleanly but log that we
 		// had nothing to do
-		Debugf("No files to parse from %s", sourcePaths)
-		os.Exit(0)
+		Debugf("No files parsed from %s", sourcePaths)
+		return prevError
 	}
 
 	if !dryRunFlag {
 		err := os.MkdirAll(outputPath, os.ModePerm)
 		if err != nil {
-			Logf("Can't create dir %s: %s", outputPath, err)
-			os.Exit(1)
+			reportError(err)
+			return prevError
 		}
 	}
 
@@ -372,33 +394,31 @@ func main() {
 		case strings.HasSuffix(name, ".network"):
 			service, err = quadlet.ConvertNetwork(unit, name)
 		default:
-			Logf("Unsupported file type '%s'", name)
+			Logf("Unsupported file type %q", name)
 			continue
 		}
 
 		if err != nil {
-			Logf("Error converting '%s', ignoring: %s", name, err)
-		} else {
-			service.Path = path.Join(outputPath, service.Filename)
-
-			if dryRunFlag {
-				data, err := service.ToString()
-				if err != nil {
-					Debugf("Error parsing %s\n---\n", service.Path)
-					exitCode = 1
-				} else {
-					fmt.Printf("---%s---\n%s\n", service.Path, data)
-				}
-			} else {
-				if err := generateServiceFile(service); err != nil {
-					Logf("Error writing '%s'o: %s", service.Path, err)
-				}
-				enableServiceFile(outputPath, service)
+			reportError(fmt.Errorf("converting %q: %w", name, err))
+			continue
+		}
+		service.Path = path.Join(outputPath, service.Filename)
+
+		if dryRunFlag {
+			data, err := service.ToString()
+			if err != nil {
+				reportError(fmt.Errorf("parsing %s: %w", service.Path, err))
+				continue
 			}
+			fmt.Printf("---%s---\n%s\n", service.Path, data)
+			continue
 		}
+		if err := generateServiceFile(service); err != nil {
+			reportError(fmt.Errorf("generating service file %s: %w", service.Path, err))
+		}
+		enableServiceFile(outputPath, service)
 	}
-
-	os.Exit(exitCode)
+	return prevError
 }
 
 func init() {