DNS: Let requests specify a callback for future cache hits

net/dns/host_resolver.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/dns/host_resolver.h"
 
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
@@ skipping 72 matching lines @@
   limits.reserved_slots = parsed;
   return limits;
 }
 
 HostResolver::Options::Options()
     : max_concurrent_resolves(kDefaultParallelism),
       max_retry_attempts(kDefaultRetryAttempts),
       enable_caching(true) {
 }
 
 HostResolver::RequestInfo::RequestInfo(const HostPortPair& host_port_pair)

[Charlie Harrison, 2016/07/26 13:41:13]

Can this constructor call into the no argument constructor to reduce the
boilerplate of default member initialization?

[Julia Tuttle, 2016/07/26 17:51:24]

Done.

     : host_port_pair_(host_port_pair),
       address_family_(ADDRESS_FAMILY_UNSPECIFIED),
       host_resolver_flags_(0),
       allow_cached_response_(true),
       is_speculative_(false),
       is_my_ip_address_(false) {}
 
+HostResolver::RequestInfo::RequestInfo(const RequestInfo& request_info)
+    : host_port_pair_(request_info.host_port_pair_),
+      address_family_(request_info.address_family_),
+      host_resolver_flags_(request_info.host_resolver_flags_),
+      allow_cached_response_(request_info.allow_cached_response_),
+      is_speculative_(request_info.is_speculative_),
+      is_my_ip_address_(request_info.is_my_ip_address_),
+      cache_hit_callback_(request_info.cache_hit_callback_) {}
+
+HostResolver::RequestInfo::~RequestInfo() {}
+
+HostResolver::RequestInfo::RequestInfo()
+    : address_family_(ADDRESS_FAMILY_UNSPECIFIED),
+      host_resolver_flags_(0),
+      allow_cached_response_(true),
+      is_speculative_(false),
+      is_my_ip_address_(false) {}
+
 HostResolver::~HostResolver() {
 }
 
 void HostResolver::SetDnsClientEnabled(bool enabled) {
 }
 
 void HostResolver::ChangeRequestPriority(RequestHandle req,
                                          RequestPriority priority) {
   NOTIMPLEMENTED();
 }
@@ skipping 17 matching lines @@
 std::unique_ptr<HostResolver> HostResolver::CreateDefaultResolver(
     NetLog* net_log) {
   return std::unique_ptr<HostResolver>(
       new HostResolverImpl(Options(), net_log));
 }
 
 HostResolver::HostResolver() {
 }
 
 }  // namespace net