Cancel the request when URLLoader is gone

content/browser/loader/mojo_async_resource_handler.cc

 // Copyright 2016 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/loader/mojo_async_resource_handler.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/time/time.h"
 #include "content/browser/loader/netlog_observer.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/loader/resource_request_info_impl.h"
 #include "content/common/resource_request_completion_status.h"
+#include "content/public/browser/global_request_id.h"
 #include "content/public/browser/resource_dispatcher_host_delegate.h"
 #include "content/public/common/resource_response.h"
 #include "mojo/public/c/system/data_pipe.h"
 #include "mojo/public/cpp/system/data_pipe.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_flags.h"
 #include "net/base/mime_sniffer.h"
 #include "net/url_request/redirect_info.h"
 
 namespace content {
@@ skipping 75 matching lines @@
     net::URLRequest* request,
     ResourceDispatcherHostImpl* rdh,
     mojo::InterfaceRequest<mojom::URLLoader> mojo_request,
     mojom::URLLoaderClientPtr url_loader_client)
     : ResourceHandler(request),
       rdh_(rdh),
       binding_(this, std::move(mojo_request)),
       url_loader_client_(std::move(url_loader_client)) {
   DCHECK(url_loader_client_);
   InitializeResourceBufferConstants();
+  // This unretained pointer is safe because the callback will never be called
+  // after |this| destruction.

[mmenke, 2016/11/03 18:17:41]

nit:  "after |this| is destroyed."

Could optionally mention that this is because it owned binding_, but think we're
fine without it.

[yhirano, 2016/11/08 11:52:23]

Done.

+  binding_.set_connection_error_handler(
+      base::Bind(&MojoAsyncResourceHandler::Cancel, base::Unretained(this)));
 }
 
 MojoAsyncResourceHandler::~MojoAsyncResourceHandler() {
   if (has_checked_for_sufficient_resources_)
     rdh_->FinishedWithResourcesForRequest(request());
 }
 
 bool MojoAsyncResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
@@ skipping 106 matching lines @@
 }
 
 void MojoAsyncResourceHandler::OnDataDownloaded(int bytes_downloaded) {
   // Not implemented.
 }
 
 void MojoAsyncResourceHandler::FollowRedirect() {
   NOTIMPLEMENTED();
 }
 
-void MojoAsyncResourceHandler::Cancel() {
-  NOTIMPLEMENTED();
-}
-
 void MojoAsyncResourceHandler::ResumeForTesting() {
   Resume();
 }
 
 void MojoAsyncResourceHandler::SetAllocationSizeForTesting(size_t size) {
   g_allocation_size = size;
 }
 
 MojoResult MojoAsyncResourceHandler::BeginWrite(void** data,
                                                 uint32_t* available) {
@@ skipping 133 matching lines @@
     return true;
 
   controller()->CancelWithError(net::ERR_INSUFFICIENT_RESOURCES);
   return false;
 }
 
 void MojoAsyncResourceHandler::OnWritable(MojoResult unused) {
   Resume();
 }
 
+void MojoAsyncResourceHandler::Cancel() {
+  const ResourceRequestInfoImpl* info = GetRequestInfo();
+  ResourceDispatcherHostImpl::Get()->CancelRequestFromRenderer(
+      GlobalRequestID(info->GetChildID(), info->GetRequestID()));
+}
+
 }  // namespace content