Make URLFetcherCore::ReleaseRequest() release |buffer_|.

net/url_request/url_fetcher_core.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 "net/url_request/url_fetcher_core.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 64 matching lines @@
                                const GURL& original_url,
                                URLFetcher::RequestType request_type,
                                URLFetcherDelegate* d)
     : fetcher_(fetcher),
       original_url_(original_url),
       request_type_(request_type),
       delegate_(d),
       delegate_task_runner_(base::SequencedTaskRunnerHandle::Get()),
       load_flags_(LOAD_NORMAL),
       response_code_(URLFetcher::RESPONSE_CODE_INVALID),
-      buffer_(new IOBuffer(kBufferSize)),
       url_request_data_key_(NULL),
       was_fetched_via_proxy_(false),
       was_cached_(false),
       received_response_content_length_(0),
       total_received_bytes_(0),
       upload_content_set_(false),
       upload_range_offset_(0),
       upload_range_length_(0),
       referrer_policy_(
           URLRequest::CLEAR_REFERRER_ON_TRANSITION_FROM_SECURE_TO_INSECURE),
@@ skipping 354 matching lines @@
   DCHECK(network_task_runner_->BelongsToCurrentThread());
 
   if (!stopped_on_redirect_)
     url_ = request->url();
   URLRequestThrottlerManager* throttler_manager =
       request->context()->throttler_manager();
   if (throttler_manager)
     url_throttler_entry_ = throttler_manager->RegisterRequestUrl(url_);
 
   while (bytes_read > 0) {
+    DCHECK(buffer_);
     current_response_bytes_ += bytes_read;
     InformDelegateDownloadProgress();
 
     const int result =
         WriteBuffer(new DrainableIOBuffer(buffer_.get(), bytes_read));
     if (result < 0) {
       // Write failed or waiting for write completion.
       return;
     }
     bytes_read = request_->Read(buffer_.get(), kBufferSize);
@@ skipping 339 matching lines @@
   CancelURLRequest(result);
   delegate_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&URLFetcherCore::InformDelegateFetchIsComplete, this));
 }
 
 void URLFetcherCore::ReleaseRequest() {
   request_context_getter_->RemoveObserver(this);
   upload_progress_checker_timer_.reset();
   request_.reset();
+  buffer_ = nullptr;
   g_registry.Get().RemoveURLFetcherCore(this);
 }
 
 base::TimeTicks URLFetcherCore::GetBackoffReleaseTime() {
   DCHECK(network_task_runner_->BelongsToCurrentThread());
 
   if (!original_url_throttler_entry_.get())
     return base::TimeTicks();
 
   base::TimeTicks original_url_backoff =
@@ skipping 52 matching lines @@
   if (request_.get())
     ReadResponse();
 }
 
 void URLFetcherCore::ReadResponse() {
   // Some servers may treat HEAD requests as GET requests. To free up the
   // network connection as soon as possible, signal that the request has
   // completed immediately, without trying to read any data back (all we care
   // about is the response code and headers, which we already have).
   int bytes_read = 0;
-  if (request_type_ != URLFetcher::HEAD)
+  if (request_type_ != URLFetcher::HEAD) {
+    if (!buffer_)
+      buffer_ = new IOBuffer(kBufferSize);

[mmenke, 2017/01/25 16:32:16]

Just do this unconditionally in OnResponseStarted, where we know it's nullptr
(Head requests are sufficiently rare that I don't think we care about them, and
we'll clean it up immediately in OnReadCompleted, anyways - actually, I think
the HEAD check would make more sense in there, too).

[xunjieli, 2017/01/25 16:41:53]

Done.

     bytes_read = request_->Read(buffer_.get(), kBufferSize);
+  }
 
   OnReadCompleted(request_.get(), bytes_read);
 }
 
 void URLFetcherCore::InformDelegateUploadProgress() {
   DCHECK(network_task_runner_->BelongsToCurrentThread());
   if (request_.get()) {
     int64_t current = request_->GetUploadProgress().position();
     if (current_upload_bytes_ != current) {
       current_upload_bytes_ = current;
@@ skipping 49 matching lines @@
 }
 
 void URLFetcherCore::AssertHasNoUploadData() const {
   DCHECK(!upload_content_set_);
   DCHECK(upload_content_.empty());
   DCHECK(upload_file_path_.empty());
   DCHECK(upload_stream_factory_.is_null());
 }
 
 }  // namespace net