From 14929d4e35a6c4760fe9376e4aa8cb10d9411539 Mon Sep 17 00:00:00 2001
From: Julien Boeuf <jboeuf@google.com>
Date: Mon, 21 Sep 2015 20:57:26 -0700
Subject: [PATCH] Credentials plugin fixes (after the branch was merged).

---
 include/grpc++/security/credentials.h | 2 +-
 src/cpp/client/secure_credentials.cc  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/grpc++/security/credentials.h b/include/grpc++/security/credentials.h
index 01b9710f6b3..fafcfdc9061 100644
--- a/include/grpc++/security/credentials.h
+++ b/include/grpc++/security/credentials.h
@@ -177,7 +177,7 @@ class MetadataCredentialsPlugin {
   // a different thread from the one processing the call.
   virtual bool IsBlocking() const { return true; }
 
-  // Gets the auth metatada produced by this plugin. */
+  // Gets the auth metatada produced by this plugin.
   virtual Status GetMetadata(
       grpc::string_ref service_url,
       std::multimap<grpc::string, grpc::string_ref>* metadata) = 0;
diff --git a/src/cpp/client/secure_credentials.cc b/src/cpp/client/secure_credentials.cc
index 8333b01f29b..99b7468e865 100644
--- a/src/cpp/client/secure_credentials.cc
+++ b/src/cpp/client/secure_credentials.cc
@@ -183,7 +183,7 @@ void MetadataCredentialsPluginWrapper::InvokePlugin(
                   0,
                   {{nullptr, nullptr, nullptr, nullptr}}});
   }
-  cb(user_data, &md[0], md.size(),
+  cb(user_data, md.empty() ? nullptr : &md[0], md.size(),
      static_cast<grpc_status_code>(status.error_code()),
      status.error_message().c_str());
 }