1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CONTENT_BROWSER_LOADER_DETACHABLE_RESOURCE_HANDLER_H_
6#define CONTENT_BROWSER_LOADER_DETACHABLE_RESOURCE_HANDLER_H_
7
8#include "base/basictypes.h"
9#include "base/compiler_specific.h"
10#include "base/memory/ref_counted.h"
11#include "base/memory/scoped_ptr.h"
12#include "base/time/time.h"
13#include "base/timer/timer.h"
14#include "content/browser/loader/resource_handler.h"
15#include "content/public/browser/resource_controller.h"
16
17namespace net {
18class IOBuffer;
19class URLRequest;
20}  // namespace net
21
22namespace content {
23
24// A ResourceHandler which delegates all calls to the next handler, unless
25// detached. Once detached, it drives the request to completion itself. This is
26// used for requests which outlive the owning renderer, such as <link
27// rel=prefetch> and <a ping>. Requests do not start out detached so, e.g.,
28// prefetches appear in DevTools and get placed in the renderer's local
29// cache. If the request does not complete after a timeout on detach, it is
30// cancelled.
31//
32// Note that, once detached, the request continues without the original next
33// handler, so any policy decisions in that handler are skipped.
34class DetachableResourceHandler : public ResourceHandler,
35                                  public ResourceController {
36 public:
37  DetachableResourceHandler(net::URLRequest* request,
38                            base::TimeDelta cancel_delay,
39                            scoped_ptr<ResourceHandler> next_handler);
40  virtual ~DetachableResourceHandler();
41
42  bool is_detached() const { return next_handler_ == NULL; }
43  void Detach();
44
45  void set_cancel_delay(base::TimeDelta cancel_delay) {
46    cancel_delay_ = cancel_delay;
47  }
48
49  // ResourceHandler implementation:
50  virtual void SetController(ResourceController* controller) OVERRIDE;
51  virtual bool OnUploadProgress(uint64 position, uint64 size) OVERRIDE;
52  virtual bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
53                                   ResourceResponse* response,
54                                   bool* defer) OVERRIDE;
55  virtual bool OnResponseStarted(ResourceResponse* response,
56                                 bool* defer) OVERRIDE;
57  virtual bool OnWillStart(const GURL& url, bool* defer) OVERRIDE;
58  virtual bool OnBeforeNetworkStart(const GURL& url, bool* defer) OVERRIDE;
59  virtual bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
60                          int* buf_size,
61                          int min_size) OVERRIDE;
62  virtual bool OnReadCompleted(int bytes_read, bool* defer) OVERRIDE;
63  virtual void OnResponseCompleted(const net::URLRequestStatus& status,
64                                   const std::string& security_info,
65                                   bool* defer) OVERRIDE;
66  virtual void OnDataDownloaded(int bytes_downloaded) OVERRIDE;
67
68  // ResourceController implementation:
69  virtual void Resume() OVERRIDE;
70  virtual void Cancel() OVERRIDE;
71  virtual void CancelAndIgnore() OVERRIDE;
72  virtual void CancelWithError(int error_code) OVERRIDE;
73
74 private:
75  scoped_ptr<ResourceHandler> next_handler_;
76  scoped_refptr<net::IOBuffer> read_buffer_;
77
78  scoped_ptr<base::OneShotTimer<DetachableResourceHandler> > detached_timer_;
79  base::TimeDelta cancel_delay_;
80
81  bool is_deferred_;
82  bool is_finished_;
83
84  DISALLOW_COPY_AND_ASSIGN(DetachableResourceHandler);
85};
86
87}  // namespace content
88
89#endif  // CONTENT_BROWSER_LOADER_DETACHABLE_RESOURCE_HANDLER_H_
90