Support replacement of IP address resolutions via command line flag

net/dns/mapped_ip_resolver.cc

Index: net/dns/mapped_ip_resolver.cc
diff --git a/net/dns/mapped_ip_resolver.cc b/net/dns/mapped_ip_resolver.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e7a0fe2d40427a9ec6aed62d7e42404406ba1805
--- /dev/null
+++ b/net/dns/mapped_ip_resolver.cc
@@ -0,0 +1,69 @@
+// Copyright (c) 2014 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/mapped_ip_resolver.h"
+
+#include "base/strings/string_util.h"
+#include "net/base/net_errors.h"
+#include "net/base/net_util.h"
+
+namespace net {
+
+MappedIPResolver::MappedIPResolver(scoped_ptr<HostResolver> impl)
+    : impl_(impl.Pass()),
+      weak_factory_(this) {
+}
+
+MappedIPResolver::~MappedIPResolver() {}
+
+int MappedIPResolver::Resolve(const RequestInfo& info,
+                              RequestPriority priority,
+                              AddressList* addresses,
+                              const CompletionCallback& original_callback,

[wtc, 2014/02/11 23:52:30]

Why did you rename this parameter "original_callback"? I think it should be
named "callback".

[jar (doing other things), 2014/02/15 21:14:56]

Done.

+                              RequestHandle* out_req,
+                              const BoundNetLog& net_log) {
+  CompletionCallback new_callback = base::Bind(&MappedIPResolver::ApplyRules,
+                                               weak_factory_.GetWeakPtr(),
+                                               original_callback, addresses);
+  int rv = impl_->Resolve(info, priority, addresses, new_callback, out_req,
+                          net_log);
+  if (rv == OK)
+    rules_.RewriteAddresses(addresses);
+  return rv;
+}
+
+int MappedIPResolver::ResolveFromCache(const RequestInfo& info,
+                                       AddressList* addresses,
+                                       const BoundNetLog& net_log) {
+  int rv = impl_->ResolveFromCache(info, addresses, net_log);
+  if (rv == OK)
+    rules_.RewriteAddresses(addresses);
+  return rv;
+}
+
+void MappedIPResolver::CancelRequest(RequestHandle req) {
+  impl_->CancelRequest(req);
+}
+
+void MappedIPResolver::SetDnsClientEnabled(bool enabled) {
+  impl_->SetDnsClientEnabled(enabled);
+}
+
+HostCache* MappedIPResolver::GetHostCache() {
+  return impl_->GetHostCache();
+}
+
+base::Value* MappedIPResolver::GetDnsConfigAsValue() const {
+  return impl_->GetDnsConfigAsValue();
+}
+
+void MappedIPResolver::ApplyRules(const CompletionCallback& original_cb,
+                                  AddressList* addresses,
+                                  int rv) const {
+  if (rv == OK)
+    rules_.RewriteAddresses(addresses);
+  original_cb.Run(rv);
+}
+
+}  // namespace net