Use overriden host name when creating a call.

Change on 2014/12/22 by yangg <yangg@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82672321

include/grpc++/channel_arguments.h

@@ -70,6 +70,9 @@ class ChannelArguments {
   ChannelArguments(const ChannelArguments&);
   ChannelArguments& operator=(const ChannelArguments&);
 
+  // Returns empty string when it is not set.
+  grpc::string GetSslTargetNameOverride() const;
+
   // Populates given channel_args with args_, does not take ownership.
   void SetChannelArgs(grpc_channel_args* channel_args) const;
 

src/cpp/client/channel.cc

@@ -64,11 +64,13 @@ Channel::Channel(const grpc::string& target, const ChannelArguments& args)
 Channel::Channel(const grpc::string& target,
                  const std::unique_ptr<Credentials>& creds,
                  const ChannelArguments& args)
-    : target_(target) {
+    : target_(args.GetSslTargetNameOverride().empty()
+                  ? target
+                  : args.GetSslTargetNameOverride()) {
   grpc_channel_args channel_args;
   args.SetChannelArgs(&channel_args);
   c_channel_ = grpc_secure_channel_create(
-      creds->GetRawCreds(), target_.c_str(),
+      creds->GetRawCreds(), target.c_str(),
       channel_args.num_args > 0 ? &channel_args : nullptr);
 }
 

src/cpp/client/channel_arguments.cc

@@ -41,6 +41,15 @@ void ChannelArguments::SetSslTargetNameOverride(const grpc::string& name) {
   SetString(GRPC_SSL_TARGET_NAME_OVERRIDE_ARG, name);
 }
 
+grpc::string ChannelArguments::GetSslTargetNameOverride() const {
+  for (int i = 0; i < args_.size(); i++) {
+    if (grpc::string(GRPC_SSL_TARGET_NAME_OVERRIDE_ARG) == args_[i].key) {
+      return args_[i].value.string;
+    }
+  }
+  return "";
+}
+
 void ChannelArguments::SetInt(const grpc::string& key, int value) {
   grpc_arg arg;
   arg.type = GRPC_ARG_INTEGER;