Refactor ResourceHandler API.

content/browser/download/save_file_resource_handler.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/download/save_file_resource_handler.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "content/browser/download/save_file_manager.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/resource_controller.h"
 #include "net/base/io_buffer.h"
 #include "net/url_request/redirect_info.h"
 #include "net/url_request/url_request_status.h"
 
 namespace content {
 
 SaveFileResourceHandler::SaveFileResourceHandler(
     net::URLRequest* request,
     SaveItemId save_item_id,
     SavePackageId save_package_id,
     int render_process_host_id,
     int render_frame_routing_id,
     const GURL& url,
     AuthorizationState authorization_state)
     : ResourceHandler(request),
       save_item_id_(save_item_id),
       save_package_id_(save_package_id),
       render_process_id_(render_process_host_id),
       render_frame_routing_id_(render_frame_routing_id),
       url_(url),
       content_length_(0),
       save_manager_(SaveFileManager::Get()),
       authorization_state_(authorization_state) {}
 
 SaveFileResourceHandler::~SaveFileResourceHandler() {
 }
 
-bool SaveFileResourceHandler::OnRequestRedirected(
+void SaveFileResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
-    bool* defer) {
+    std::unique_ptr<ResourceController> controller) {
   final_url_ = redirect_info.new_url;
-  return true;
+  controller->Resume();
 }
 
-bool SaveFileResourceHandler::OnResponseStarted(ResourceResponse* response,
-                                                bool* defer) {
+void SaveFileResourceHandler::OnResponseStarted(
+    ResourceResponse* response,
+    std::unique_ptr<ResourceController> controller) {
   // |save_manager_| consumes (deletes):
   SaveFileCreateInfo* info = new SaveFileCreateInfo(
       url_, final_url_, save_item_id_, save_package_id_, render_process_id_,
       render_frame_routing_id_, GetRequestID(), content_disposition_,
       content_length_);
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&SaveFileManager::StartSave, save_manager_, info));
-  return true;
+  controller->Resume();
 }
 
-bool SaveFileResourceHandler::OnWillStart(const GURL& url, bool* defer) {
-  return authorization_state_ == AuthorizationState::AUTHORIZED;
+void SaveFileResourceHandler::OnWillStart(
+    const GURL& url,
+    std::unique_ptr<ResourceController> controller) {
+  if (authorization_state_ == AuthorizationState::AUTHORIZED) {
+    controller->Resume();
+  } else {
+    controller->Cancel();
+  }
 }
 
 bool SaveFileResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                          int* buf_size,
                                          int min_size) {
   DCHECK_EQ(AuthorizationState::AUTHORIZED, authorization_state_);
   DCHECK(buf && buf_size);
   if (!read_buffer_.get()) {
     *buf_size = min_size < 0 ? kReadBufSize : min_size;
     read_buffer_ = new net::IOBuffer(*buf_size);
   }
   *buf = read_buffer_.get();
   return true;
 }
 
-bool SaveFileResourceHandler::OnReadCompleted(int bytes_read, bool* defer) {
+void SaveFileResourceHandler::OnReadCompleted(
+    int bytes_read,
+    std::unique_ptr<ResourceController> controller) {
   DCHECK_EQ(AuthorizationState::AUTHORIZED, authorization_state_);
   DCHECK(read_buffer_.get());
   // We are passing ownership of this buffer to the save file manager.
   scoped_refptr<net::IOBuffer> buffer;
   read_buffer_.swap(buffer);
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&SaveFileManager::UpdateSaveProgress, save_manager_,
                  save_item_id_, base::RetainedRef(buffer), bytes_read));
-  return true;
+  controller->Resume();

[mmenke, 2016/12/01 17:20:46]

Ahh...This is the one without back pressure.

[Randy Smith (Not in Mondays), 2016/12/16 21:37:26]

Ah, yuck.

On the bright side, It's only involved after the resource has been downloaded
once, and only in response to user request.  So something like a GZIP bomb is
unlikely.

I'll file a bug on this.

 }
 
 void SaveFileResourceHandler::OnResponseCompleted(
     const net::URLRequestStatus& status,
-    bool* defer) {
+    std::unique_ptr<ResourceController> controller) {
   if (authorization_state_ != AuthorizationState::AUTHORIZED)
     DCHECK(!status.is_success());
 
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&SaveFileManager::SaveFinished, save_manager_, save_item_id_,
                  save_package_id_,
                  status.is_success() && !status.is_io_pending()));
-  read_buffer_ = NULL;
+  read_buffer_ = nullptr;
+  controller->Resume();
 }
 
 void SaveFileResourceHandler::OnDataDownloaded(int bytes_downloaded) {
   NOTREACHED();
 }
 
 void SaveFileResourceHandler::set_content_length(
     const std::string& content_length) {
   base::StringToInt64(content_length, &content_length_);
 }
 
 }  // namespace content