updated TestProcIOStats test

On this test we assumed that there would always be reading stats for our
own process /proc/self, but on restricted environments that might not
alwys be the case. Anyway, a value of 0 is not an error in itself.

Closes #1075

daemon/procmon/details.go

@@ -304,10 +304,10 @@ func (p *Process) readDescriptors() {
 	}
 }
 
-func (p *Process) readIOStats() {
+func (p *Process) readIOStats() (err error) {
 	f, err := os.Open(p.pathIO)
 	if err != nil {
-		return
+		return err
 	}
 	defer f.Close()
 
@@ -318,19 +318,21 @@ func (p *Process) readIOStats() {
 		s := strings.Split(scanner.Text(), " ")
 		switch s[0] {
 		case "rchar:":
-			p.IOStats.RChar, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.RChar, err = strconv.ParseInt(s[1], 10, 64)
 		case "wchar:":
-			p.IOStats.WChar, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.WChar, err = strconv.ParseInt(s[1], 10, 64)
 		case "syscr:":
-			p.IOStats.SyscallRead, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.SyscallRead, err = strconv.ParseInt(s[1], 10, 64)
 		case "syscw:":
-			p.IOStats.SyscallWrite, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.SyscallWrite, err = strconv.ParseInt(s[1], 10, 64)
 		case "read_bytes:":
-			p.IOStats.ReadBytes, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.ReadBytes, err = strconv.ParseInt(s[1], 10, 64)
 		case "write_bytes:":
-			p.IOStats.WriteBytes, _ = strconv.ParseInt(s[1], 10, 64)
+			p.IOStats.WriteBytes, err = strconv.ParseInt(s[1], 10, 64)
 		}
 	}
+
+	return err
 }
 
 func (p *Process) readStatus() {

daemon/procmon/process_test.go

@@ -61,26 +61,11 @@ func TestProcEnv(t *testing.T) {
 }
 
 func TestProcIOStats(t *testing.T) {
-	proc.readIOStats()
+	err := proc.readIOStats()
 
-	if proc.IOStats.RChar == 0 {
-		t.Error("Proc.IOStats.RChar should not be 0:", proc.IOStats)
+	if err != nil {
+		t.Error("error reading proc IOStats:", err)
 	}
-	if proc.IOStats.WChar == 0 {
-		t.Error("Proc.IOStats.WChar should not be 0:", proc.IOStats)
-	}
-	if proc.IOStats.SyscallRead == 0 {
-		t.Error("Proc.IOStats.SyscallRead should not be 0:", proc.IOStats)
-	}
-	if proc.IOStats.SyscallWrite == 0 {
-		t.Error("Proc.IOStats.SyscallWrite should not be 0:", proc.IOStats)
-	}
-	/*if proc.IOStats.ReadBytes == 0 {
-		t.Error("Proc.IOStats.ReadBytes should not be 0:", proc.IOStats)
-	}
-	if proc.IOStats.WriteBytes == 0 {
-		t.Error("Proc.IOStats.WriteBytes should not be 0:", proc.IOStats)
-	}*/
 }
 
 func TestProcStatus(t *testing.T) {