add detecting virtualization system on Linux.

host.go

@@ -14,6 +14,9 @@ type HostInfoStat struct {
 	Platform             string `json:"platform"`       // ex: ubuntu, linuxmint
 	PlatformFamily       string `json:"platformFamily"` // ex: debian, rhel
 	PlatformVersion      string `json:"platformVersion"`
+	VirtualizationSystem string `json:"virtualizationSystem"`
+	VirtualizationRole   string `json:"virtualizationRole"` // guest or host
+
 }
 
 type UserStat struct {

host_freebsd.go

@@ -26,14 +26,16 @@ func HostInfo() (*HostInfoStat, error) {
 	}
 	ret.Hostname = hostname
 
-	out, err := exec.Command("uname", "-s").Output()
+	platform, family, version, err := GetPlatformInformation()
 	if err == nil {
-		ret.Platform = strings.ToLower(strings.TrimSpace(string(out)))
+		ret.Platform = platform
+		ret.PlatformFamily = family
+		ret.PlatformVersion = version
 	}
-
-	out, err = exec.Command("uname", "-r").Output()
+	system, role, err := GetVirtualization()
 	if err == nil {
-		ret.PlatformVersion = strings.ToLower(strings.TrimSpace(string(out)))
+		ret.VirtualizationSystem = system
+		ret.VirtualizationRole = role
 	}
 
 	values, err := doSysctrl("kern.boottime")
@@ -101,3 +103,28 @@ func Users() ([]UserStat, error) {
 	return ret, nil
 
 }
+
+func GetPlatformInformation() (string, string, string, error) {
+	platform := ""
+	family := ""
+	version := ""
+
+	out, err := exec.Command("uname", "-s").Output()
+	if err == nil {
+		platform = strings.ToLower(strings.TrimSpace(string(out)))
+	}
+
+	out, err = exec.Command("uname", "-r").Output()
+	if err == nil {
+		version = strings.ToLower(strings.TrimSpace(string(out)))
+	}
+
+	return platform, family, version, nil
+}
+
+func GetVirtualization() (string, string, error) {
+	system := ""
+	role := ""
+
+	return system, role, nil
+}

host_linux.go

@@ -32,12 +32,17 @@ func HostInfo() (*HostInfoStat, error) {
 		OS:       runtime.GOOS,
 	}
 
-	platform, family, version, err := getPlatformInformation()
+	platform, family, version, err := GetPlatformInformation()
 	if err == nil {
 		ret.Platform = platform
 		ret.PlatformFamily = family
 		ret.PlatformVersion = version
 	}
+	system, role, err := GetVirtualization()
+	if err == nil {
+		ret.VirtualizationSystem = system
+		ret.VirtualizationRole = role
+	}
 	uptime, err := BootTime()
 	if err == nil {
 		ret.Uptime = uptime
@@ -145,7 +150,7 @@ func getLSB() (*LSB, error) {
 	return ret, nil
 }
 
-func getPlatformInformation() (string, string, string, error) {
+func GetPlatformInformation() (string, string, string, error) {
 	platform := ""
 	family := ""
 	version := ""
@@ -252,3 +257,88 @@ func getRedhatishVersion(contents []string) (string, error) {
 func getRedhatishPlatform(contents []string) (string, error) {
 	return "", nil
 }
+
+func GetVirtualization() (string, string, error) {
+	var system string
+	var role string
+
+	if pathExists("/proc/xen") {
+		system = "xen"
+		role = "guest" // assume guest
+
+		if pathExists("/proc/xen/capabilities") {
+			contents, err := readLines("/proc/xen/capabilities")
+			if err == nil {
+				if stringContains(contents, "control_d") {
+					role = "host"
+				}
+			}
+		}
+	}
+	if pathExists("/proc/modules") {
+		contents, err := readLines("/proc/modules")
+		if err == nil {
+			if stringContains(contents, "kvm") {
+				system = "kvm"
+				role = "host"
+			} else if stringContains(contents, "vboxdrv") {
+				system = "vbox"
+				role = "host"
+			} else if stringContains(contents, "vboxguest") {
+				system = "vbox"
+				role = "guest"
+			}
+		}
+	}
+
+	if pathExists("/proc/cpuinfo") {
+		contents, err := readLines("/proc/cpuinfo")
+		if err == nil {
+			if stringContains(contents, "QEMU Virtual CPU") ||
+				stringContains(contents, "Common KVM processor") ||
+				stringContains(contents, "Common 32-bit KVM processor") {
+				system = "kvm"
+				role = "guest"
+			}
+		}
+	}
+
+	if pathExists("/proc/bc/0") {
+		system = "openvz"
+		role = "host"
+	} else if pathExists("/proc/vz") {
+		system = "openvz"
+		role = "guest"
+	}
+
+	// not use dmidecode because it requires root
+
+	if pathExists("/proc/self/status") {
+		contents, err := readLines("/proc/self/status")
+		if err == nil {
+
+			if stringContains(contents, "s_context:") ||
+				stringContains(contents, "VxID:") {
+				system = "linux-vserver"
+			}
+			// TODO: guest or host
+		}
+	}
+
+	if pathExists("/proc/self/cgroup") {
+		contents, err := readLines("/proc/self/cgroup")
+		if err == nil {
+
+			if stringContains(contents, "lxc") ||
+				stringContains(contents, "docker") {
+				system = "lxc"
+				role = "guest"
+			} else if pathExists("/usr/bin/lxc-version") { // TODO: which
+				system = "lxc"
+				role = "host"
+			}
+		}
+	}
+
+	return system, role, nil
+}

test/host_test.go

@@ -49,7 +49,7 @@ func TestHostInfoStat_String(t *testing.T) {
 		OS:       "linux",
 		Platform: "ubuntu",
 	}
-	e := `{"hostname":"test","uptime":3000,"procs":100,"os":"linux","platform":"ubuntu","platformFamily":"","platformVersion":""}`
+	e := `{"hostname":"test","uptime":3000,"procs":100,"os":"linux","platform":"ubuntu","platformFamily":"","platformVersion":"","virtualizationSystem":"","virtualizationRole":""}`
 	if e != fmt.Sprintf("%v", v) {
 		t.Errorf("HostInfoStat string is invalid: %v", v)
 	}