Reuse container traits from base objects

2 files changed, 62 insertions, 14 deletions

diff --git a/odb/mysql/container-statements.hxx b/odb/mysql/container-statements.hxx
index a5e93a1..7124be7 100644
--- a/odb/mysql/container-statements.hxx
+++ b/odb/mysql/container-statements.hxx
@@ -25,7 +25,8 @@ namespace odb
   {
     class connection;
 
-    // Template argument is the generated container traits type.
+    // Template argument is the generated abstract container traits type.
+    // That is, it doesn't need to provide column counts and statements.
     //
     template <typename T>
     class container_statements
@@ -166,7 +167,7 @@ namespace odb
         if (insert_one_ == 0)
           insert_one_.reset (
             new (details::shared) insert_statement_type (
-              conn_, traits::insert_one_statement, data_image_binding_));
+              conn_, insert_one_text_, data_image_binding_));
 
         return *insert_one_;
       }
@@ -178,7 +179,7 @@ namespace odb
           select_all_.reset (
             new (details::shared) select_statement_type (
               conn_,
-              traits::select_all_statement,
+              select_all_text_,
               cond_image_binding_,
               data_image_binding_));
 
@@ -191,7 +192,7 @@ namespace odb
         if (delete_all_ == 0)
           delete_all_.reset (
             new (details::shared) delete_statement_type (
-              conn_, traits::delete_all_statement, cond_image_binding_));
+              conn_, delete_all_text_, cond_image_binding_));
 
         return *delete_all_;
       }
@@ -200,7 +201,7 @@ namespace odb
       container_statements (const container_statements&);
       container_statements& operator= (const container_statements&);
 
-    private:
+    protected:
       connection_type& conn_;
       functions_type functions_;
 
@@ -210,19 +211,44 @@ namespace odb
       std::size_t cond_image_version_;
       std::size_t cond_id_binding_version_;
       binding cond_image_binding_;
-      MYSQL_BIND cond_image_bind_[traits::cond_column_count];
+      MYSQL_BIND* cond_image_bind_;
 
       data_image_type data_image_;
       std::size_t data_image_version_;
       std::size_t data_id_binding_version_;
       binding data_image_binding_;
-      MYSQL_BIND data_image_bind_[traits::data_column_count];
-      my_bool data_image_truncated_[traits::data_column_count];
+      MYSQL_BIND* data_image_bind_;
+      my_bool* data_image_truncated_;
+
+      const char* insert_one_text_;
+      const char* select_all_text_;
+      const char* delete_all_text_;
 
       details::shared_ptr<insert_statement_type> insert_one_;
       details::shared_ptr<select_statement_type> select_all_;
       details::shared_ptr<delete_statement_type> delete_all_;
     };
+
+    // Template argument is the generated concrete container traits type.
+    //
+    template <typename T>
+    class container_statements_impl: public T::statements_type
+    {
+    public:
+      typedef T traits;
+      typedef typename T::statements_type base;
+
+      container_statements_impl (connection&);
+
+    private:
+      container_statements_impl (const container_statements_impl&);
+      container_statements_impl& operator= (const container_statements_impl&);
+
+    private:
+      MYSQL_BIND cond_image_bind_array_[traits::cond_column_count];
+      MYSQL_BIND data_image_bind_array_[traits::data_column_count];
+      my_bool data_image_truncated_array_[traits::data_column_count];
+    };
   }
 }
 
diff --git a/odb/mysql/container-statements.txx b/odb/mysql/container-statements.txx
index ba6827c..a651bd4 100644
--- a/odb/mysql/container-statements.txx
+++ b/odb/mysql/container-statements.txx
@@ -22,8 +22,8 @@ namespace odb
                       &traits::load_all,
                       &traits::delete_all),
           id_binding_ (0),
-          cond_image_binding_ (cond_image_bind_, traits::cond_column_count),
-          data_image_binding_ (data_image_bind_, traits::data_column_count)
+          cond_image_binding_ (0, 0), // Initialized by impl.
+          data_image_binding_ (0, 0)  // Initialized by impl.
     {
       cond_image_.version = 0;
       cond_image_version_ = 0;
@@ -32,13 +32,35 @@ namespace odb
       data_image_.version = 0;
       data_image_version_ = 0;
       data_id_binding_version_ = 0;
+    }
+
+    template <typename T>
+    container_statements_impl<T>::
+    container_statements_impl (connection& conn)
+        : base (conn)
+    {
+      this->cond_image_bind_ = cond_image_bind_array_;
+      this->data_image_bind_ = data_image_bind_array_;
+      this->data_image_truncated_ = data_image_truncated_array_;
 
-      std::memset (cond_image_bind_, 0, sizeof (cond_image_bind_));
-      std::memset (data_image_bind_, 0, sizeof (data_image_bind_));
-      std::memset (data_image_truncated_, 0, sizeof (data_image_truncated_));
+      this->cond_image_binding_.bind = this->cond_image_bind_;
+      this->cond_image_binding_.count = traits::cond_column_count;
+
+      this->data_image_binding_.bind = this->data_image_bind_;
+      this->data_image_binding_.count = traits::data_column_count;
+
+      std::memset (cond_image_bind_array_, 0, sizeof (cond_image_bind_array_));
+      std::memset (data_image_bind_array_, 0, sizeof (data_image_bind_array_));
+      std::memset (data_image_truncated_array_,
+                   0,
+                   sizeof (data_image_truncated_array_));
 
       for (std::size_t i (0); i < traits::data_column_count; ++i)
-        data_image_bind_[i].error = data_image_truncated_ + i;
+        data_image_bind_array_[i].error = data_image_truncated_array_ + i;
+
+      this->insert_one_text_ = traits::insert_one_statement;
+      this->select_all_text_ = traits::select_all_statement;
+      this->delete_all_text_ = traits::delete_all_statement;
     }
   }
 }