fixed parsing of the raspberry pi's kernel version

host/detect.go

@@ -30,25 +30,34 @@ func nodeName() (string, error) {
 	return execOutput("uname", "-n")
 }
 
+func parseVersion(str string) (major, minor, patch int, err error) {
+	parts := strings.Split(str, ".")
+	len := len(parts)
+
+	if major, err = strconv.Atoi(parts[0]); err != nil {
+		return 0, 0, 0, err
+	}
+	if minor, err = strconv.Atoi(parts[1]); err != nil {
+		return 0, 0, 0, err
+	}
+	if len > 2 {
+		part := parts[2]
+		part = strings.TrimSuffix(part, "+")
+		if patch, err = strconv.Atoi(part); err != nil {
+			return 0, 0, 0, err
+		}
+	}
+
+	return major, minor, patch, err
+}
+
 func kernelVersion() (major, minor, patch int, err error) {
 	output, err := execOutput("uname", "-r")
 	if err != nil {
-		return
+		return 0, 0, 0, err
 	}
 
-	parts := strings.Split(output, ".")
-
-	if major, err = strconv.Atoi(parts[0]); err != nil {
-		return
-	}
-	if minor, err = strconv.Atoi(parts[1]); err != nil {
-		return
-	}
-	if patch, err = strconv.Atoi(parts[2]); err != nil {
-		return
-	}
-
-	return
+	return parseVersion(output)
 }
 
 func Detect() (Host, int, error) {

host/detect_test.go

@@ -0,0 +1,37 @@
+package host
+
+import "testing"
+
+func TestKernelVersionParse(t *testing.T) {
+	var tests = []struct {
+		versionStr          string
+		major, minor, patch int
+	}{
+		{
+			"3.8",
+			3, 8, 0,
+		},
+		{
+			"3.7",
+			3, 7, 0,
+		},
+		{
+			"3.8.2",
+			3, 8, 2,
+		},
+		{
+			"3.8.10+",
+			3, 8, 10,
+		},
+	}
+	for _, test := range tests {
+		major, minor, patch, err := parseVersion(test.versionStr)
+		if err != nil {
+			t.Errorf("Failed parsing %q: %v", test.versionStr, err)
+			continue
+		}
+		if major != test.major || minor != test.minor || patch != test.patch {
+			t.Errorf("Parse of %q: got (%v, %v, %v) want (%v, %v, %v)", test.versionStr, major, minor, patch, test.major, test.minor, test.patch)
+		}
+	}
+}