Merge pull request #160 from sergeken/master

Added for update support (issue #145)

include/sqlpp11/for_update.h

@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2017, Serge Robyns
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_FOR_UPDATE_H
+#define SQLPP_FOR_UPDATE_H
+
+#include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/type_traits.h>
+
+namespace sqlpp
+{
+  // FOR_UPDATE DATA
+  struct for_update_data_t
+  {
+  };
+
+  // FOR_UPDATE
+  struct for_update_t
+  {
+    using _traits = make_traits<no_value_t, tag::is_for_update>;
+    using _nodes = detail::type_vector<>;
+
+    // Data
+    using _data_t = for_update_data_t;
+
+    // Member implementation with data and methods
+    template <typename Policies>
+    struct _impl_t
+    {
+      // workaround for msvc bug https://connect.microsoft.com/VisualStudio/Feedback/Details/2091069
+      _impl_t() = default;
+      _impl_t(const _data_t& data) : _data(data)
+      {
+      }
+
+      _data_t _data;
+    };
+
+    // Base template to be inherited by the statement
+    template <typename Policies>
+    struct _base_t
+    {
+      using _data_t = for_update_data_t;
+
+      // workaround for msvc bug https://connect.microsoft.com/VisualStudio/Feedback/Details/2091069
+      template <typename... Args>
+      _base_t(Args&&... args) : for_update{std::forward<Args>(args)...}
+      {
+      }
+
+      _impl_t<Policies> for_update;
+      _impl_t<Policies>& operator()()
+      {
+        return for_update;
+      }
+      const _impl_t<Policies>& operator()() const
+      {
+        return for_update;
+      }
+
+      template <typename T>
+      static auto _get_member(T t) -> decltype(t.for_update)
+      {
+        return t.for_update;
+      }
+
+      using _consistency_check = consistent_t;
+    };
+  };
+
+  struct no_for_update_t
+  {
+    using _traits = make_traits<no_value_t, tag::is_noop>;
+    using _nodes = detail::type_vector<>;
+
+    // Data
+    using _data_t = no_data_t;
+
+    // Member implementation with data and methods
+    template <typename Policies>
+    struct _impl_t
+    {
+      // workaround for msvc bug https://connect.microsoft.com/VisualStudio/Feedback/Details/2091069
+      _impl_t() = default;
+      _impl_t(const _data_t& data) : _data(data)
+      {
+      }
+
+      _data_t _data;
+    };
+
+    // Base template to be inherited by the statement
+    template <typename Policies>
+    struct _base_t
+    {
+      using _data_t = no_data_t;
+
+      // workaround for msvc bug https://connect.microsoft.com/VisualStudio/Feedback/Details/2091069
+      template <typename... Args>
+      _base_t(Args&&... args) : no_for_update{std::forward<Args>(args)...}
+      {
+      }
+
+      _impl_t<Policies> no_for_update;
+      _impl_t<Policies>& operator()()
+      {
+        return no_for_update;
+      }
+      const _impl_t<Policies>& operator()() const
+      {
+        return no_for_update;
+      }
+
+      template <typename T>
+      static auto _get_member(T t) -> decltype(t.no_for_update)
+      {
+        return t.no_for_update;
+      }
+
+      using _database_t = typename Policies::_database_t;
+
+      template <typename Check, typename T>
+      using _new_statement_t = new_statement_t<Check, Policies, no_for_update_t, T>;
+
+      using _consistency_check = consistent_t;
+
+      auto for_update() const -> _new_statement_t<consistent_t, for_update_t>
+      {
+        return {static_cast<const derived_statement_t<Policies>&>(*this), for_update_data_t{}};
+      }
+    };
+  };
+
+  // Interpreters
+  template <typename Context>
+  struct serializer_t<Context, for_update_data_t>
+  {
+    using _serialize_check = serialize_check_of<Context>;
+    using T = for_update_data_t;
+
+    static Context& _(const T& t, Context& context)
+    {
+      context << " FOR UPDATE ";
+      return context;
+    }
+  };
+
+  template <typename T>
+  auto for_update(T&& t) -> decltype(statement_t<void, no_for_update_t>().for_update(std::forward<T>(t)))
+  {
+    return statement_t<void, no_for_update_t>().for_update(std::forward<T>(t));
+  }
+}
+
+#endif

include/sqlpp11/select.h

@@ -40,6 +40,7 @@
 #include <sqlpp11/having.h>
 #include <sqlpp11/order_by.h>
 #include <sqlpp11/limit.h>
+#include <sqlpp11/for_update.h>
 #include <sqlpp11/offset.h>
 #include <sqlpp11/union.h>
 #include <sqlpp11/expression.h>
@@ -82,7 +83,8 @@ namespace sqlpp
                                      no_order_by_t,
                                      no_limit_t,
                                      no_offset_t,
-                                     no_union_t>;
+                                     no_union_t,
+                                     no_for_update_t>;
 
   inline blank_select_t<void> select()  // FIXME: These should be constexpr
   {

include/sqlpp11/type_traits.h

@@ -200,6 +200,7 @@ namespace sqlpp
   SQLPP_VALUE_TRAIT_GENERATOR(is_having)
   SQLPP_VALUE_TRAIT_GENERATOR(is_order_by)
   SQLPP_VALUE_TRAIT_GENERATOR(is_limit)
+  SQLPP_VALUE_TRAIT_GENERATOR(is_for_update)
   SQLPP_VALUE_TRAIT_GENERATOR(is_offset)
   SQLPP_VALUE_TRAIT_GENERATOR(is_using_)
   SQLPP_VALUE_TRAIT_GENERATOR(is_column_list)

tests/Select.cpp

@@ -107,6 +107,14 @@ int Select(int, char* [])
     std::cout << a << ", " << b << ", " << g << std::endl;
   }
 
+  for (const auto& row : db(select(all_of(t).as(t), t.gamma).from(t).where(t.alpha > 7).for_update()))
+  {
+    int64_t a = row.tabBar.alpha;
+    const std::string b = row.tabBar.beta;
+    const bool g = row.gamma;
+    std::cout << a << ", " << b << ", " << g << std::endl;
+  }
+
   for (const auto& row :
        db(select(all_of(t), all_of(f)).from(t.join(f).on(t.alpha > f.omega and not t.gamma)).unconditionally()))
   {