Add flag to run ipmi-sel with sudo, because syscall.Setuid() does not…

… work on Linux

main.go

@@ -9,6 +9,7 @@ import (
 	"os/exec"
 	"path"
 	"strings"
+	"syscall"
 
 	"github.com/sirupsen/logrus"
 	logSys "github.com/sirupsen/logrus/hooks/syslog"
@@ -22,6 +23,7 @@ var (
 	debug      = app.Flag("debug", "if set, enables debug logging").Default("false").Bool()
 	syslogHook = app.Flag("syslog", "if set, enables logging to syslog").Default("false").Bool()
 	deadman    = app.Flag("deadman", "if set, this program will always print something").Default("false").Bool()
+	useSudo    = app.Flag("sudo", "if set, this program will use sudo to run ipmi-sel").Default("true").Bool()
 	eventTime  = app.Flag("event-time", "if set, the event time will be used instead of current time (Use --no-event-time to set to false)").Default("true").Bool()
 	ipmiSel    = app.Flag("ipmi-sel", "Path of ipmi-sel").Default("/usr/sbin/ipmi-sel").String()
 )
@@ -47,12 +49,23 @@ func main() {
 		log.SetFlags(log.Lshortfile)
 	}
 
+	if uid := syscall.Getuid(); !*useSudo && uid != 0 {
+		logrus.Fatal("Needs to be executed with UID 0, but it is running with UID ", uid)
+	}
+
 	hostname, err := os.Hostname()
 	if err != nil {
 		logrus.Fatal(err)
 	}
 
-	out, err := exec.Command(*ipmiSel, "--debug", "--output-event-state", "--comma-separated-output", "--no-header-output").Output()
+	args := []string{"--debug", "--output-event-state", "--comma-separated-output", "--no-header-output"}
+	cmd := exec.Command(*ipmiSel, args...)
+	if *useSudo {
+		args = append([]string{*ipmiSel}, args...)
+		cmd = exec.Command("sudo", args...)
+	}
+
+	out, err := cmd.Output()
 	outStr := string(out)
 	if err != nil {
 		logrus.Errorf("Got error running `%s`: `%s` : `%s`", *ipmiSel, err, outStr) // purposely do not quit