From 8f49c7aa670c49c95958ded24c65bab6790d3614 Mon Sep 17 00:00:00 2001
From: Holger Obermaier <40787752+ho-ob@users.noreply.github.com>
Date: Thu, 5 Feb 2026 14:48:49 +0100
Subject: [PATCH] Fixed Error return value of  is not checked (errcheck)

---
 collectors/cpufreqCpuinfoMetric.go | 13 +++++++++++--
 collectors/cpustatMetric.go        | 12 ++++++++++--
 collectors/diskstatMetric.go       | 12 ++++++++++--
 collectors/iostatMetric.go         | 12 ++++++++++--
 collectors/likwidMetric.go         | 12 ++++++++++--
 collectors/memstatMetric.go        |  6 +++++-
 collectors/netstatMetric.go        | 12 ++++++++++--
 collectors/numastatsMetric.go      |  6 +++++-
 collectors/schedstatMetric.go      | 12 ++++++++++--
 9 files changed, 81 insertions(+), 16 deletions(-)

diff --git a/collectors/cpufreqCpuinfoMetric.go b/collectors/cpufreqCpuinfoMetric.go
index 3c66cac..014bc09 100644
--- a/collectors/cpufreqCpuinfoMetric.go
+++ b/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()
diff --git a/collectors/cpustatMetric.go b/collectors/cpustatMetric.go
index fdb9cde..50c322a 100644
--- a/collectors/cpustatMetric.go
+++ b/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() {
diff --git a/collectors/diskstatMetric.go b/collectors/diskstatMetric.go
index 8176790..0d9d266 100644
--- a/collectors/diskstatMetric.go
+++ b/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)
diff --git a/collectors/iostatMetric.go b/collectors/iostatMetric.go
index e429d4d..d93056b 100644
--- a/collectors/iostatMetric.go
+++ b/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() {
diff --git a/collectors/likwidMetric.go b/collectors/likwidMetric.go
index 74a65a5..d38128b 100644
--- a/collectors/likwidMetric.go
+++ b/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)
diff --git a/collectors/memstatMetric.go b/collectors/memstatMetric.go
index ba035f4..e8a0612 100644
--- a/collectors/memstatMetric.go
+++ b/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() {
diff --git a/collectors/netstatMetric.go b/collectors/netstatMetric.go
index 57833a4..e9dd131 100644
--- a/collectors/netstatMetric.go
+++ b/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() {
diff --git a/collectors/numastatsMetric.go b/collectors/numastatsMetric.go
index 969ef23..b528918 100644
--- a/collectors/numastatsMetric.go
+++ b/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))
+		}
 	}
 }
 
diff --git a/collectors/schedstatMetric.go b/collectors/schedstatMetric.go
index a9ce9df..1f5ee5a 100644
--- a/collectors/schedstatMetric.go
+++ b/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() {