Implement incoming rate limit (fixes #613)

cmd/syncthing/limitedreader.go

@@ -0,0 +1,24 @@
+// Copyright (C) 2014 Jakob Borg and Contributors (see the CONTRIBUTORS file).
+// All rights reserved. Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"io"
+
+	"github.com/juju/ratelimit"
+)
+
+type limitedReader struct {
+	r      io.Reader
+	bucket *ratelimit.Bucket
+}
+
+func (r *limitedReader) Read(buf []byte) (int, error) {
+	n, err := r.r.Read(buf)
+	if r.bucket != nil {
+		r.bucket.Wait(int64(n))
+	}
+	return n, err
+}