make ros log to dmesg

Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au>

log/showuserlog.go

@@ -0,0 +1,40 @@
+package log
+
+import (
+	"fmt"
+	"github.com/Sirupsen/logrus"
+	"os"
+)
+
+// ShowuserlogHook writes all levels of logrus entries to a file for later analysis
+type ShowuserlogHook struct {
+	Level logrus.Level
+}
+
+func NewShowuserlogHook(l logrus.Level) (*ShowuserlogHook, error) {
+	return &ShowuserlogHook{l}, nil
+}
+
+func (hook *ShowuserlogHook) Fire(entry *logrus.Entry) error {
+	line, err := entry.String()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Unable to read entry, %v", err)
+		return err
+	}
+
+	if entry.Level <= hook.Level {
+		fmt.Printf("> %s", line)
+	}
+	return nil
+}
+
+func (hook *ShowuserlogHook) Levels() []logrus.Level {
+	return []logrus.Level{
+		logrus.DebugLevel,
+		logrus.InfoLevel,
+		logrus.WarnLevel,
+		logrus.ErrorLevel,
+		logrus.FatalLevel,
+		logrus.PanicLevel,
+	}
+}