Fixed Error return value of is not checked (errcheck)

collectors/cpufreqCpuinfoMetric.go

@@ -57,7 +57,6 @@ func (m *CPUFreqCpuInfoCollector) Init(config json.RawMessage) error {
 	if err != nil {
 		return fmt.Errorf("failed to open file '%s': %v", cpuInfoFile, err)
 	}
-	defer file.Close()
 
 	// Collect topology information from file cpuinfo
 	foundFreq := false
@@ -87,6 +86,10 @@ func (m *CPUFreqCpuInfoCollector) Init(config json.RawMessage) error {
 			}
 		}
 
+		if err := file.Close(); err != nil {
+			return fmt.Errorf("%s Init(): Call to file.Close() failed: %w", m.name, err)
+		}
+
 		// were all topology information collected?
 		if foundFreq &&
 			len(processor) > 0 &&
@@ -141,7 +144,13 @@ func (m *CPUFreqCpuInfoCollector) Read(interval time.Duration, output chan lp.CC
 			fmt.Sprintf("Read(): Failed to open file '%s': %v", cpuInfoFile, err))
 		return
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", cpuInfoFile, err))
+		}
+	}()
 
 	processorCounter := 0
 	now := time.Now()

collectors/cpustatMetric.go

@@ -157,9 +157,17 @@ func (m *CpustatCollector) Read(interval time.Duration, output chan lp.CCMessage
 
 	file, err := os.Open(string(CPUSTATFILE))
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("Read(): Failed to open file '%s': %v", string(CPUSTATFILE), err))
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", string(CPUSTATFILE), err))
+		}
+	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {

collectors/diskstatMetric.go

@@ -72,10 +72,18 @@ func (m *DiskstatCollector) Read(interval time.Duration, output chan lp.CCMessag
 
 	file, err := os.Open(MOUNTFILE)
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("Read(): Failed to open file '%s': %v", MOUNTFILE, err))
 		return
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", MOUNTFILE, err))
+		}
+	}()
 
 	part_max_used := uint64(0)
 	scanner := bufio.NewScanner(file)

collectors/iostatMetric.go

@@ -141,10 +141,18 @@ func (m *IOstatCollector) Read(interval time.Duration, output chan lp.CCMessage)
 
 	file, err := os.Open(IOSTATFILE)
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("Read(): Failed to open file '%s': %v", IOSTATFILE, err))
 		return
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", IOSTATFILE, err))
+		}
+	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {

collectors/likwidMetric.go

@@ -386,10 +386,18 @@ func (m *LikwidCollector) takeMeasurement(evidx int, evset LikwidEventsetConfig,
 	// Watch changes for the lock file ()
 	watcher, err := fsnotify.NewWatcher()
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("takeMeasurement(): Failed to create a new fsnotify.Watcher: %v", err))
 		return true, err
 	}
-	defer watcher.Close()
+	defer func() {
+		if err := watcher.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("takeMeasurement(): Failed to close fsnotify.Watcher: %v", err))
+		}
+	}()
 	if len(m.config.LockfilePath) > 0 {
 		// Check if the lock file exists
 		info, err := os.Stat(m.config.LockfilePath)

collectors/memstatMetric.go

@@ -58,7 +58,11 @@ func getStats(filename string) map[string]MemstatStats {
 	if err != nil {
 		cclog.Error(err.Error())
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.Error(err.Error())
+		}
+	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {

collectors/netstatMetric.go

@@ -197,10 +197,18 @@ func (m *NetstatCollector) Read(interval time.Duration, output chan lp.CCMessage
 
 	file, err := os.Open(NETSTATFILE)
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("Read(): Failed to open file '%s': %v", NETSTATFILE, err))
 		return
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", NETSTATFILE, err))
+		}
+	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {

collectors/numastatsMetric.go

@@ -188,7 +188,11 @@ func (m *NUMAStatsCollector) Read(interval time.Duration, output chan lp.CCMessa
 				t.previousValues[key] = value
 			}
 		}
-		file.Close()
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", t.file, err))
+		}
 	}
 }
 

collectors/schedstatMetric.go

@@ -137,9 +137,17 @@ func (m *SchedstatCollector) Read(interval time.Duration, output chan lp.CCMessa
 
 	file, err := os.Open(string(SCHEDSTATFILE))
 	if err != nil {
-		cclog.ComponentError(m.name, err.Error())
+		cclog.ComponentError(
+			m.name,
+			fmt.Sprintf("Read(): Failed to open file '%s': %v", string(SCHEDSTATFILE), err))
 	}
-	defer file.Close()
+	defer func() {
+		if err := file.Close(); err != nil {
+			cclog.ComponentError(
+				m.name,
+				fmt.Sprintf("Read(): Failed to close file '%s': %v", string(SCHEDSTATFILE), err))
+		}
+	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {