// Copyright 2015 Google Inc. All Rights Reserved.
//
// 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.

// +build !go1.5

package transport

import "net/http"

// makeReqCancel returns a closure that cancels the given http.Request
// when called.
func makeReqCancel(req *http.Request) func(http.RoundTripper) {
	// Go 1.4 and prior do not have a reliable way of cancelling a request.
	// Transport.CancelRequest will only work if the request is already in-flight.
	return func(r http.RoundTripper) {
		if t, ok := r.(*http.Transport); ok {
			t.CancelRequest(req)
		}
	}
}
