From ce7a59fb568011d5bd4172596db6fcf74c6fba82 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20M=C3=A4kel=C3=A4?= <markus.makela@mariadb.com>
Date: Fri, 31 Aug 2018 07:37:50 +0300
Subject: [PATCH] Allow mxs::rworker_local<const T>

By removing the constness of the type for the actual stored value, the
return values of the access operators are defined by the type itself. This
allows both const and non-const types to be stored in a rworker_local
object.
---
 include/maxscale/routingworker.hh | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/include/maxscale/routingworker.hh b/include/maxscale/routingworker.hh
index b8dda0e64..43ca156d6 100644
--- a/include/maxscale/routingworker.hh
+++ b/include/maxscale/routingworker.hh
@@ -17,6 +17,7 @@
 #include <unordered_map>
 #include <vector>
 #include <mutex>
+#include <type_traits>
 
 #include <maxbase/semaphore.hh>
 #include <maxbase/worker.hh>
@@ -462,14 +463,14 @@ public:
         mxs_rworker_delete_data(m_handle);
     }
 
-    // Converts to a const T reference
-    operator const T&() const
+    // Converts to a T reference
+    operator T&() const
     {
         return *get_local_value();
     }
 
     // Arrow operator
-    const T* operator->() const
+    T* operator->() const
     {
         return get_local_value();
     }
@@ -494,9 +495,9 @@ public:
 
 private:
 
-    uint64_t           m_handle;
-    mutable std::mutex m_lock;
-    T                  m_value; // The "master" value, never used directly
+    uint64_t                            m_handle; // The handle to the worker local data
+    typename std::remove_const<T>::type m_value;  // The master value, never used directly
+    mutable std::mutex                  m_lock;   // Protects the master value
 
 private: