gras: created element factory

3 files changed, 238 insertions, 0 deletions

diff --git a/include/gras/CMakeLists.txt b/include/gras/CMakeLists.txt
index 38cb233..72d2fa6 100644
--- a/include/gras/CMakeLists.txt
+++ b/include/gras/CMakeLists.txt
@@ -11,6 +11,7 @@ install(FILES
     block.i
     element.hpp
     element.i
+    factory.hpp
     gras.hpp
     hier_block.hpp
     hier_block.i
@@ -39,6 +40,7 @@ install(FILES
     detail/block.hpp
     detail/chrono.hpp
     detail/element.hpp
+    detail/factory.hpp
     detail/sbuffer.hpp
     detail/work_buffer.hpp
 
diff --git a/include/gras/detail/factory.hpp b/include/gras/detail/factory.hpp
new file mode 100644
index 0000000..0487e76
--- /dev/null
+++ b/include/gras/detail/factory.hpp
@@ -0,0 +1,151 @@
+// Copyright (C) by Josh Blum. See LICENSE.txt for licensing information.
+
+#ifndef INCLUDED_GRAS_DETAIL_FACTORY_HPP
+#define INCLUDED_GRAS_DETAIL_FACTORY_HPP
+
+#include <PMC/Containers.hpp> //PMCList
+
+namespace gras
+{
+
+/***********************************************************************
+ * Factory entry base class
+ **********************************************************************/
+struct GRAS_API FactoryRegistryEntry
+{
+    FactoryRegistryEntry(void);
+    virtual ~FactoryRegistryEntry(void);
+    virtual Element *make(const PMCC &args) = 0;
+};
+
+/***********************************************************************
+ * Templated registration - 0 args
+ **********************************************************************/
+template <typename ReturnType>
+struct FactoryRegistryEntryImpl0 : FactoryRegistryEntry
+{
+    typedef ReturnType(*Fcn)(void);
+    FactoryRegistryEntryImpl0(Fcn fcn):_fcn(fcn){}
+    Element *make(const PMCC &)
+    {
+        return _fcn();
+    }
+    Fcn _fcn;
+};
+
+template <typename ReturnType>
+void Factory::register_make(const std::string &name, ReturnType(*fcn)(void))
+{
+    void *r = new FactoryRegistryEntryImpl0<ReturnType>(fcn);
+    Factory::_register_make(name, r);
+}
+
+/***********************************************************************
+ * Templated registration - 1 args
+ **********************************************************************/
+template <typename ReturnType, typename Arg0>
+struct FactoryRegistryEntryImpl1 : FactoryRegistryEntry
+{
+    typedef ReturnType(*Fcn)(const Arg0 &);
+    FactoryRegistryEntryImpl1(Fcn fcn):_fcn(fcn){}
+    Element *make(const PMCC &args)
+    {
+        const PMCList &a = args.as<PMCList>();
+        return _fcn(a[0].safe_as<Arg0>());
+    }
+    Fcn _fcn;
+};
+
+template <typename ReturnType, typename Arg0>
+void Factory::register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &))
+{
+    void *r = new FactoryRegistryEntryImpl1<ReturnType, Arg0>(fcn);
+    Factory::_register_make(name, r);
+}
+
+/***********************************************************************
+ * Templated registration - 2 args
+ **********************************************************************/
+template <typename ReturnType, typename Arg0, typename Arg1>
+struct FactoryRegistryEntryImpl2 : FactoryRegistryEntry
+{
+    typedef ReturnType(*Fcn)(const Arg0 &, const Arg1 &);
+    FactoryRegistryEntryImpl2(Fcn fcn):_fcn(fcn){}
+    Element *make(const PMCC &args)
+    {
+        const PMCList &a = args.as<PMCList>();
+        return _fcn(a[0].safe_as<Arg0>(), a[1].safe_as<Arg1>());
+    }
+    Fcn _fcn;
+};
+
+template <typename ReturnType, typename Arg0, typename Arg1>
+void Factory::register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &, const Arg1 &))
+{
+    void *r = new FactoryRegistryEntryImpl2<ReturnType, Arg0, Arg1>(fcn);
+    Factory::_register_make(name, r);
+}
+
+/***********************************************************************
+ * Templated registration - 3 args
+ **********************************************************************/
+template <typename ReturnType, typename Arg0, typename Arg1, typename Arg2>
+struct FactoryRegistryEntryImpl3 : FactoryRegistryEntry
+{
+    typedef ReturnType(*Fcn)(const Arg0 &, const Arg1 &, const Arg2 &);
+    FactoryRegistryEntryImpl3(Fcn fcn):_fcn(fcn){}
+    Element *make(const PMCC &args)
+    {
+        const PMCList &a = args.as<PMCList>();
+        return _fcn(a[0].safe_as<Arg0>(), a[1].safe_as<Arg1>(), a[2].safe_as<Arg2>());
+    }
+    Fcn _fcn;
+};
+
+template <typename ReturnType, typename Arg0, typename Arg1, typename Arg2>
+void Factory::register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &, const Arg1 &, const Arg2 &))
+{
+    void *r = new FactoryRegistryEntryImpl3<ReturnType, Arg0, Arg1, Arg2>(fcn);
+    Factory::_register_make(name, r);
+}
+
+/***********************************************************************
+ * Templated make implementations
+ **********************************************************************/
+inline
+Element *Factory::make(const std::string &name)
+{
+    PMCList args(0);
+    return Factory::_make(name, PMC_M(args));
+}
+
+template <typename Arg0>
+Element *Factory::make(const std::string &name, const Arg0 &a0)
+{
+    PMCList args(1);
+    args[0] = PMC_M(a0);
+    return Factory::_make(name, PMC_M(args));
+}
+
+template <typename Arg0, typename Arg1>
+Element *Factory::make(const std::string &name, const Arg0 &a0, const Arg1 &a1)
+{
+    PMCList args(2);
+    args[0] = PMC_M(a0);
+    args[1] = PMC_M(a1);
+    return Factory::_make(name, PMC_M(args));
+}
+
+template <typename Arg0, typename Arg1, typename Arg2>
+Element *Factory::make(const std::string &name, const Arg0 &a0, const Arg1 &a1, const Arg2 &a2)
+{
+    PMCList args(3);
+    args[0] = PMC_M(a0);
+    args[1] = PMC_M(a1);
+    args[2] = PMC_M(a2);
+    return Factory::_make(name, PMC_M(args));
+}
+
+}
+
+#endif /*INCLUDED_GRAS_DETAIL_FACTORY_HPP*/
diff --git a/include/gras/factory.hpp b/include/gras/factory.hpp
new file mode 100644
index 0000000..926025e
--- /dev/null
+++ b/include/gras/factory.hpp
@@ -0,0 +1,85 @@
+// Copyright (C) by Josh Blum. See LICENSE.txt for licensing information.
+
+#ifndef INCLUDED_GRAS_FACTORY_HPP
+#define INCLUDED_GRAS_FACTORY_HPP
+
+#include <gras/gras.hpp>
+#include <gras/element.hpp>
+#include <PMC/PMC.hpp>
+#include <string>
+
+//! A fixture for static initialization code
+#define GRAS_STATIC_BLOCK(name) \
+    static struct name ## _static_fixture__ \
+    { \
+        name ## _static_fixture__(void); \
+    } name ## _static_fixture_instance__; \
+    name ## _static_fixture__::name ## _static_fixture__(void)
+
+/*!
+ * Register a block's factory function:
+ * Declare this macro at the global scope in a cpp file.
+ * The block will register at static initialization time.
+ */
+#define GRAS_REGISTER_FACTORY(name) \
+    GRAS_STATIC_BLOCK(name) \
+    {gras::Factory::register_make(#name, &name);}
+
+namespace gras
+{
+
+/*!
+ * Element factory:
+ *  - Register factory functions into the global factory.
+ *  - Call make() to create element from global factory.
+ *
+ * Example register a factory function:
+ *  gras::Factory::register_make("make_my_block", &make_my_block);
+ *
+ * Example call into the factory:
+ *  gras::Element *my_block = gras::Factory::make("make_my_block", arg0, arg1);
+ */
+class GRAS_API Factory : Callable
+{
+public:
+
+    /*******************************************************************
+     * Register API - don't look here, template magic, not helpful
+     ******************************************************************/
+    template <typename ReturnType>
+    static void register_make(const std::string &name, ReturnType(*fcn)(void));
+
+    template <typename ReturnType, typename Arg0>
+    static void register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &));
+
+    template <typename ReturnType, typename Arg0, typename Arg1>
+    static void register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &, const Arg1 &));
+
+    template <typename ReturnType, typename Arg0, typename Arg1, typename Arg2>
+    static void register_make(const std::string &name, ReturnType(*fcn)(const Arg0 &, const Arg1 &, const Arg2 &));
+
+    /*******************************************************************
+     * Make API - don't look here, template magic, not helpful
+     ******************************************************************/
+    inline
+    static Element *make(const std::string &name);
+
+    template <typename Arg0>
+    static Element *make(const std::string &name, const Arg0 &a0);
+
+    template <typename Arg0, typename Arg1>
+    static Element *make(const std::string &name, const Arg0 &a0, const Arg1 &a1);
+
+    template <typename Arg0, typename Arg1, typename Arg2>
+    static Element *make(const std::string &name, const Arg0 &a0, const Arg1 &a1, const Arg2 &a2);
+
+private:
+    static void _register_make(const std::string &, void *);
+    static Element *_make(const std::string &, const PMCC &);
+};
+
+}
+
+#include <gras/detail/factory.hpp>
+
+#endif /*INCLUDED_GRAS_FACTORY_HPP*/