First commit

logger.go

@@ -0,0 +1,27 @@
+package proxyprotocol
+
+// Logger interface
+type Logger interface {
+	Printf(format string, v ...interface{})
+}
+
+// LoggerFunc wrap Printf-like function into proxyprotocol.Logger
+type LoggerFunc func(format string, v ...interface{})
+
+// Printf call inner Printf-link function
+func (logf LoggerFunc) Printf(format string, v ...interface{}) {
+	logf(format, v...)
+}
+
+// FallbackLogger wrap Logger or nil
+type FallbackLogger struct {
+	Logger
+}
+
+// Printf call Printf on inner logger if it not nil
+func (wrapper FallbackLogger) Printf(format string, v ...interface{}) {
+	if wrapper.Logger == nil {
+		return
+	}
+	wrapper.Logger.Printf(format, v...)
+}