mgmt: respond with 414 if StrategyChoice prefix is too long

refs #4262

Change-Id: Ief6dec02d7fbf372382a167e04d82e48777fa30b
diff --git a/daemon/mgmt/strategy-choice-manager.cpp b/daemon/mgmt/strategy-choice-manager.cpp
index 9732bd2..6cb5d57 100644
--- a/daemon/mgmt/strategy-choice-manager.cpp
+++ b/daemon/mgmt/strategy-choice-manager.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014-2017,  Regents of the University of California,
+/*
+ * Copyright (c) 2014-2018,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -57,7 +57,7 @@
   StrategyChoice::InsertResult res = m_table.insert(prefix, strategy);
   if (!res) {
     NFD_LOG_DEBUG("strategy-choice/set(" << prefix << "," << strategy << "): cannot-create " << res);
-    return done(ControlResponse(404, boost::lexical_cast<std::string>(res)));
+    return done(ControlResponse(res.getStatusCode(), boost::lexical_cast<std::string>(res)));
   }
 
   NFD_LOG_DEBUG("strategy-choice/set(" << prefix << "," << strategy << "): OK");
diff --git a/daemon/table/strategy-choice.hpp b/daemon/table/strategy-choice.hpp
index 8cfa93b..5965ddc 100644
--- a/daemon/table/strategy-choice.hpp
+++ b/daemon/table/strategy-choice.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2017,  Regents of the University of California,
+ * Copyright (c) 2014-2018,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -83,12 +83,20 @@
       return m_status == OK || m_status == EXCEPTION;
     }
 
+    /** \brief get a status code for use in management command response
+     */
+    int
+    getStatusCode() const
+    {
+      return static_cast<int>(m_status);
+    }
+
   private:
     enum Status {
-      OK,
-      NOT_REGISTERED,
-      EXCEPTION,
-      DEPTH_EXCEEDED
+      OK             = 200,
+      NOT_REGISTERED = 404,
+      EXCEPTION      = 409,
+      DEPTH_EXCEEDED = 414,
     };
 
     // implicitly constructible from Status