Mange ciricular reference to HttpNetworkTransaction in HttpProxyClientSocktPool.

net/http/http_proxy_client_socket_pool.cc

 // Copyright (c) 2010 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/http/http_proxy_client_socket_pool.h"
 
 #include "base/time.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/net_errors.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_proxy_client_socket.h"
 #include "net/socket/client_socket_factory.h"
 #include "net/socket/client_socket_handle.h"
 #include "net/socket/client_socket_pool_base.h"
 
 namespace net {
 
 HttpProxySocketParams::HttpProxySocketParams(
     const scoped_refptr<TCPSocketParams>& proxy_server,
     const GURL& request_url,
     HostPortPair endpoint,
     scoped_refptr<HttpNetworkSession> session,
     bool tunnel)
     : tcp_params_(proxy_server),
       request_url_(request_url),
       endpoint_(endpoint),
-      session_(session),
+      session_(tunnel ? session : NULL),
       tunnel_(tunnel) {
 }
 
 HttpProxySocketParams::~HttpProxySocketParams() {}
 
 // HttpProxyConnectJobs will time out after this many seconds.  Note this is on
 // top of the timeout for the transport socket.
 static const int kHttpProxyConnectJobTimeoutInSeconds = 30;
 
 HttpProxyConnectJob::HttpProxyConnectJob(
@@ skipping 101 matching lines @@
   HostPortPair proxy_server(tcp_destination.hostname(),
                             tcp_destination.port());
 
   // Add a HttpProxy connection on top of the tcp socket.
   socket_.reset(new HttpProxyClientSocket(tcp_socket_handle_.release(),
                                           params_->request_url(),
                                           params_->endpoint(),
                                           proxy_server,
                                           params_->session(),
                                           params_->tunnel()));
-  return socket_->Connect(&callback_);
+  int result = socket_->Connect(&callback_);
+
+  // Clear the circular reference to HttpNetworkSession (|params_| reference
+  // HttpNetworkSession, which reference HttpProxyClientSocketPool, which
+  // references |this|) here because it is safe to do so now but not at other
+  // points.  This may cancel this ConnectJob.
+  params_ = NULL;
+  return result;
 }
 
 int HttpProxyConnectJob::DoHttpProxyConnectComplete(int result) {
   if (result == OK || result == ERR_PROXY_AUTH_REQUESTED)
       set_socket(socket_.release());
 
   return result;
 }
 
 ConnectJob*
@@ skipping 64 matching lines @@
     const std::string& group_name) const {
   return base_.IdleSocketCountInGroup(group_name);
 }
 
 LoadState HttpProxyClientSocketPool::GetLoadState(
     const std::string& group_name, const ClientSocketHandle* handle) const {
   return base_.GetLoadState(group_name, handle);
 }
 
 }  // namespace net