table: NameTree::getEntry

NameTree::get is renamed to NameTree::lookup.
NameTree::getEntry is introduced to return the NameTreeEntry on which a table entry is attached.
tableEntry::m_nameTreeEntry is changed to weak_ptr to avoid circular shared_ptr reference.

refs #3608, #3619

Change-Id: I425b6a2eb5fe3024bbaff4ff766eb6739be54b02
diff --git a/daemon/table/strategy-choice-entry.hpp b/daemon/table/strategy-choice-entry.hpp
index 857a313..9261039 100644
--- a/daemon/table/strategy-choice-entry.hpp
+++ b/daemon/table/strategy-choice-entry.hpp
@@ -1,12 +1,12 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014,  Regents of the University of California,
- *                      Arizona Board of Regents,
- *                      Colorado State University,
- *                      University Pierre & Marie Curie, Sorbonne University,
- *                      Washington University in St. Louis,
- *                      Beijing Institute of Technology,
- *                      The University of Memphis
+ * Copyright (c) 2014-2016,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
  *
  * This file is part of NFD (Named Data Networking Forwarding Daemon).
  * See AUTHORS.md for complete list of NFD authors and contributors.
@@ -21,7 +21,7 @@
  *
  * You should have received a copy of the GNU General Public License along with
  * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
- **/
+ */
 
 #ifndef NFD_DAEMON_TABLE_STRATEGY_CHOICE_ENTRY_HPP
 #define NFD_DAEMON_TABLE_STRATEGY_CHOICE_ENTRY_HPP
@@ -33,10 +33,10 @@
 class NameTree;
 namespace name_tree {
 class Entry;
-}
+} // namespace name_tree
 namespace fw {
 class Strategy;
-}
+} // namespace fw
 
 namespace strategy_choice {
 
@@ -63,7 +63,7 @@
   Name m_prefix;
   fw::Strategy* m_strategy;
 
-  shared_ptr<name_tree::Entry> m_nameTreeEntry;
+  weak_ptr<name_tree::Entry> m_nameTreeEntry;
   friend class nfd::NameTree;
   friend class nfd::name_tree::Entry;
 };