improve yamux logging (#4952)

pkg/util/xlog/log_writer.go

@@ -0,0 +1,65 @@
+// Copyright 2025 The frp Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package xlog
+
+import "strings"
+
+// LogWriter forwards writes to frp's logger at configurable level.
+// It is safe for concurrent use as long as the underlying Logger is thread-safe.
+type LogWriter struct {
+	xl      *Logger
+	logFunc func(string)
+}
+
+func (w LogWriter) Write(p []byte) (n int, err error) {
+	msg := strings.TrimSpace(string(p))
+	w.logFunc(msg)
+	return len(p), nil
+}
+
+func NewTraceWriter(xl *Logger) LogWriter {
+	return LogWriter{
+		xl:      xl,
+		logFunc: func(msg string) { xl.Tracef("%s", msg) },
+	}
+}
+
+func NewDebugWriter(xl *Logger) LogWriter {
+	return LogWriter{
+		xl:      xl,
+		logFunc: func(msg string) { xl.Debugf("%s", msg) },
+	}
+}
+
+func NewInfoWriter(xl *Logger) LogWriter {
+	return LogWriter{
+		xl:      xl,
+		logFunc: func(msg string) { xl.Infof("%s", msg) },
+	}
+}
+
+func NewWarnWriter(xl *Logger) LogWriter {
+	return LogWriter{
+		xl:      xl,
+		logFunc: func(msg string) { xl.Warnf("%s", msg) },
+	}
+}
+
+func NewErrorWriter(xl *Logger) LogWriter {
+	return LogWriter{
+		xl:      xl,
+		logFunc: func(msg string) { xl.Errorf("%s", msg) },
+	}
+}