first commit

logger.go

@@ -0,0 +1,32 @@
+package engine
+
+import (
+	"io"
+	"log"
+)
+
+type LogWriter struct {
+	io.Writer
+	origin io.Writer
+}
+
+func (w *LogWriter) Write(data []byte) (n int, err error) {
+	if n, err = w.Writer.Write(data); err != nil {
+		go log.SetOutput(w.origin)
+	}
+	return w.origin.Write(data)
+}
+
+func AddWriter(wn io.Writer) {
+	log.SetOutput(&LogWriter{
+		Writer: wn,
+		origin: log.Writer(),
+	})
+}
+
+func MayBeError(info error) (hasError bool) {
+	if hasError = info != nil; hasError {
+		log.Print(info)
+	}
+	return
+}