1 files changed, 26 insertions, 23 deletions
diff --git a/bin-src/diff-pem2html.go b/bin-src/diff-pem2html.go
index efe253b..c0d3e7d 100644
--- a/bin-src/diff-pem2html.go
+++ b/bin-src/diff-pem2html.go
@@ -5,29 +5,16 @@ package main
 import (
 	"crypto/x509"
 	"encoding/pem"
+	"errors"
 	"fmt"
 	"html/template"
-	"io/ioutil"
+	"io"
 	"os"
 
 	"git.lukeshu.com/dashboard/bin-src/util"
 )
 
-func handleErr(err error, str string, a ...interface{}) {
-	a = append([]interface{}{err}, a...)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, str, a...)
-		os.Exit(1)
-	}
-}
-
-func handleBool(ok bool, str string, a ...interface{}) {
-	if !ok {
-		fmt.Fprintf(os.Stderr, str, a...)
-		os.Exit(1)
-	}
-}
-
+//nolint:gochecknoglobals // would be const
 var tmpl = template.Must(template.New("pem2html").
 	Funcs(template.FuncMap{
 		"htmlcell": util.HTMLCellEscapeString,
@@ -65,8 +52,17 @@ func (cert Cert) Class() string {
 }
 
 func main() {
-	data, err := ioutil.ReadAll(os.Stdin)
-	handleErr(err, "Error reading stdin: %v\n")
+	if err := mainWithError(); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "%s: error: %v", os.Args[0], err)
+		os.Exit(1)
+	}
+}
+
+func mainWithError() error {
+	data, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		return fmt.Errorf("reading stdin: %w", err)
+	}
 
 	var certs []Cert
 	a := 0
@@ -79,10 +75,14 @@ func main() {
 		var cert Cert
 
 		cert.Url, ok = certPem.Headers["X-Crt-Sh-Url"]
-		handleBool(ok, "Did not get X-Crt-Sh-Url\n")
+		if !ok {
+			return errors.New("did not get X-Crt-Sh-Url")
+		}
 
 		cert.action, ok = certPem.Headers["X-Diff-Action"]
-		handleBool(ok, "Did not get X-Diff-Action\n")
+		if !ok {
+			return errors.New("did not get X-Diff-Action")
+		}
 		switch cert.action {
 		case "add":
 			b++
@@ -92,7 +92,7 @@ func main() {
 			a++
 			b++
 		default:
-			handleBool(false, "Unknown X-Diff-Action: %q\n", cert.action)
+			return fmt.Errorf("unknown X-Diff-Action: %q", cert.action)
 		}
 
 		cert.X509, err = x509.ParseCertificate(certPem.Bytes)
@@ -103,9 +103,12 @@ func main() {
 		certs = append(certs, cert)
 	}
 
-	handleErr(tmpl.Execute(os.Stdout, map[string]interface{}{
+	if err := tmpl.Execute(os.Stdout, map[string]any{
 		"certs":  certs,
 		"nTLS":   a,
 		"nCrtSh": b,
-	}), "Could not execute template: %v\n")
+	}); err != nil {
+		return fmt.Errorf("could not execute template: %w", err)
+	}
+	return nil
 }