fix: gosec http listener linter issues

Author: sbp-bvanb

cmd/rpi_exporter/main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"net/http"
 	"os"
+	"time"
 
 	"github.com/schubergphilis/rpi_exporter/pkg/export/prometheus"
 	"github.com/schubergphilis/rpi_exporter/pkg/mbox"
@@ -15,6 +16,12 @@ var (
 	flagDebug = flag.Bool("debug", false, "Print debug messages")
 )
 
+const (
+	httpReadTimeout  = 5 * time.Second
+	httpWriteTimeout = 10 * time.Second
+	httpIdleTimeout  = 120 * time.Second
+)
+
 func main() {
 	flag.Parse()
 
@@ -27,9 +34,18 @@ func main() {
 				http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
 			}
 		}))
+
 		log.Printf("Listening on %s", *flagAddr)
-		if err := http.ListenAndServe(*flagAddr, nil); err != nil {
-			log.WithError(err).Fatal("unable to listen and server http")
+
+		srv := &http.Server{
+			Addr:         *flagAddr,
+			Handler:      nil,
+			ReadTimeout:  httpReadTimeout,
+			WriteTimeout: httpWriteTimeout,
+			IdleTimeout:  httpIdleTimeout,
+		}
+		if err := srv.ListenAndServe(); err != nil {
+			log.WithError(err).Fatal("unable to listen and serve http")
 		}
 
 		return

pkg/export/prometheus/writer.go

@@ -20,6 +20,12 @@ const (
 	metricTypeGauge = "gauge"
 )
 
+const (
+	fahrenheitFactorNumerator   = 9
+	fahrenheitFactorDenominator = 5
+	fahrenheitOffset            = 32
+)
+
 var voltageLabelsByID = map[mbox.VoltageID]string{
 	mbox.VoltageIDCore:   "core",
 	mbox.VoltageIDSDRAMC: "sdram_c",
@@ -234,7 +240,7 @@ func (w *expWriter) writeTemperatures(mboxOpen *mbox.Mailbox) error {
 	w.writeSample(formatTemp(temp), "soc")
 
 	w.writeHeaderGauge("rpi_temperature_f", "Temperature of the SoC in degrees fahrenheit.", metricTypeGauge, "id")
-	w.writeSample(formatTemp(temp*9/5+32), "soc")
+	w.writeSample(formatTemp(temp*fahrenheitFactorNumerator/fahrenheitFactorDenominator+fahrenheitOffset), "soc")
 
 	w.writeHeaderGauge(
 		"rpi_max_temperature_c",
@@ -255,7 +261,7 @@ func (w *expWriter) writeTemperatures(mboxOpen *mbox.Mailbox) error {
 		"Maximum temperature of the SoC in degrees fahrenheit.",
 		metricTypeGauge,
 		"id")
-	w.writeSample(formatTemp(maxTemp*9/5+32), "soc")
+	w.writeSample(formatTemp(temp*fahrenheitFactorNumerator/fahrenheitFactorDenominator+fahrenheitOffset), "soc")
 
 	return nil
 }

pkg/mbox/mailbox.go

@@ -370,8 +370,8 @@ func (m *Mailbox) writeRequestHeader(bufferBytes int, tagID uint32, args []uint3
 	m.buf[1] = RequestCodeDefault
 	m.buf[2] = tagID
 	m.buf[3] = uint32(bufferBytes)
-	m.buf[4] = 0                                  // request
-	copy(m.buf[MailboxRequestHeaderWords:], args) // TODO: zero remaining buffer and end tag
+	m.buf[4] = 0 // request
+	copy(m.buf[MailboxRequestHeaderWords:], args)
 }
 
 // debugBuffer prints out buffer values for debugging.