WIP - Refactor programmatic downloads

content/browser/download/url_downloader.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_DOWNLOAD_URL_DOWNLOADER_H_
+#define CONTENT_BROWSER_DOWNLOAD_URL_DOWNLOADER_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "content/browser/download/download_request_handle.h"
+#include "content/common/content_export.h"
+#include "net/url_request/url_request.h"
+
+namespace content {
+
+class DownloadRequestModel;
+class DownloadUrlParameters;
+
+// TODO(asanka): This can't be committed as-is. Figure out which
+// ResourceThrottles we need to support for explicit downloads and implement
+// support for those.
+//
+// The code is used by Content menu -> Save * As and support for the download
+// attribute. Requests that are handled by the resource dispatcher host
+// typically go through a series of resource throttles. These requests need to
+// at least support some of that functionality. Otherwise using the download
+// attribute would allow a user to make a request that would otherwise be
+// blocked by the ManagedModeResourceThrottle.
+class UrlDownloader : public net::URLRequest::Delegate {
+ public:
+  CONTENT_EXPORT static scoped_ptr<DownloadRequestHandle> CreateDownloadRequest(
+      scoped_ptr<DownloadUrlParameters> params);
+
+ private:
+  friend class base::DeleteHelper<UrlDownloader>;
+  friend struct base::DefaultDeleter<UrlDownloader>;
+
+  class RequestHandle;
+  typedef DownloadRequestHandle::RequestStartedCallback RequestStartedCallback;
+
+  UrlDownloader(scoped_ptr<DownloadUrlParameters> params);
+  virtual ~UrlDownloader();
+
+  void Start(const RequestStartedCallback& callback);
+  void PauseRequest();
+  void ResumeRequest();
+  void CancelRequest();
+
+  void ReadNextChunk();
+  void HandleCompletedRead(int bytes_read);
+
+  // net::URLRequest::Delegate.
+  virtual void OnReceivedRedirect(net::URLRequest* request,
+                                  const GURL& new_url,
+                                  bool* defer_redirect) OVERRIDE;
+  virtual void OnResponseStarted(net::URLRequest* request) OVERRIDE;
+  virtual void OnReadCompleted(net::URLRequest* request,
+                               int bytes_read) OVERRIDE;
+
+  scoped_ptr<DownloadUrlParameters> params_;
+  scoped_ptr<net::URLRequest> request_;
+  scoped_ptr<DownloadRequestModel> request_model_;
+  RequestStartedCallback started_callback_;
+
+  // Used with ChildProcessSecurityPolicy to determine whether the download URL
+  // and any redirects are allowed.
+  int child_process_id_;
+  bool is_request_active_;
+
+  DISALLOW_COPY_AND_ASSIGN(UrlDownloader);
+};
+
+}  // namespace content
+
+#endif