[ON HOLD] Deallocate read buffer in MDnsClientImpl::SocketHandler if done reading

net/dns/mdns_client_impl.cc

 // 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.
 
 #include "net/dns/mdns_client_impl.h"
 
 #include <algorithm>
 #include <queue>
 #include <utility>
 
@@ skipping 43 matching lines @@
     if (socket)
       sockets->push_back(std::move(socket));
   }
 }
 
 MDnsConnection::SocketHandler::SocketHandler(
     std::unique_ptr<DatagramServerSocket> socket,
     MDnsConnection* connection)
     : socket_(std::move(socket)),
       connection_(connection),
-      response_(dns_protocol::kMaxMulticastSize),
+      response_(new DnsResponse(dns_protocol::kMaxMulticastSize)),
       send_in_progress_(false) {}
 
 MDnsConnection::SocketHandler::~SocketHandler() {
 }
 
 int MDnsConnection::SocketHandler::Start() {
   IPEndPoint end_point;
   int rv = socket_->GetLocalAddress(&end_point);
   if (rv != OK)
     return rv;
   DCHECK(end_point.GetFamily() == ADDRESS_FAMILY_IPV4 ||
          end_point.GetFamily() == ADDRESS_FAMILY_IPV6);
   multicast_addr_ = GetMDnsIPEndPoint(end_point.GetFamily());
-  return DoLoop(0);
+  return DoRead(0);
 }
 
-int MDnsConnection::SocketHandler::DoLoop(int rv) {
+int MDnsConnection::SocketHandler::DoRead(int rv) {
+  DCHECK(response_);
   do {
     if (rv > 0)
-      connection_->OnDatagramReceived(&response_, recv_addr_, rv);
+      connection_->OnDatagramReceived(response_.get(), recv_addr_, rv);
 
     rv = socket_->RecvFrom(
-        response_.io_buffer(), response_.io_buffer()->size(), &recv_addr_,
+        response_->io_buffer(), response_->io_buffer()->size(), &recv_addr_,
         base::Bind(&MDnsConnection::SocketHandler::OnDatagramReceived,
                    base::Unretained(this)));
   } while (rv > 0);
 
-  if (rv != ERR_IO_PENDING)
-    return rv;
-
-  return OK;
+  if (rv == ERR_IO_PENDING)
+    return OK;
+  response_.reset();
+  return rv;
 }
 
 void MDnsConnection::SocketHandler::OnDatagramReceived(int rv) {
   if (rv >= OK)
-    rv = DoLoop(rv);
+    rv = DoRead(rv);
 
-  if (rv != OK)
+  if (rv != OK) {
+    response_.reset();
     connection_->PostOnError(this, rv);
+  }
 }
 
 void MDnsConnection::SocketHandler::Send(const scoped_refptr<IOBuffer>& buffer,
                                          unsigned size) {
   if (send_in_progress_) {
     send_queue_.push(std::make_pair(buffer, size));
     return;
   }
   int rv = socket_->SendTo(buffer.get(),
                            size,
@@ skipping 627 matching lines @@
 
 void MDnsTransactionImpl::OnNsecRecord(const std::string& name, unsigned type) {
   TriggerCallback(RESULT_NSEC, NULL);
 }
 
 void MDnsTransactionImpl::OnCachePurged() {
   // TODO(noamsml): Cache purge situations not yet implemented
 }
 
 }  // namespace net