1 files changed, 277 insertions, 0 deletions
diff --git a/boost/dll/import.hpp b/boost/dll/import.hpp
new file mode 100644
index 0000000000..dcf3086a18
--- /dev/null
+++ b/boost/dll/import.hpp
@@ -0,0 +1,277 @@
+// Copyright 2014 Renato Tegon Forti, Antony Polukhin.
+// Copyright 2015-2016 Antony Polukhin.
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_DLL_IMPORT_HPP
+#define BOOST_DLL_IMPORT_HPP
+
+#include <boost/config.hpp>
+#include <boost/utility/enable_if.hpp>
+#include <boost/type_traits/is_object.hpp>
+#include <boost/make_shared.hpp>
+#include <boost/dll/shared_library.hpp>
+#include <boost/utility/addressof.hpp>
+#include <boost/move/move.hpp>
+
+#if defined(BOOST_NO_CXX11_TRAILING_RESULT_TYPES) || defined(BOOST_NO_CXX11_DECLTYPE) || defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) || defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+#   include <boost/function.hpp>
+#endif
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+# pragma once
+#endif
+
+/// \file boost/dll/import.hpp
+/// \brief Contains all the boost::dll::import* reference counting
+/// functions that hold a shared pointer to the instance of
+/// boost::dll::shared_library.
+
+namespace boost { namespace dll {
+
+
+namespace detail {
+
+    template <class T>
+    class library_function {
+        // Copying of `boost::dll::shared_library` is very expensive, so we use a `shared_ptr` to make it faster.
+        boost::shared_ptr<T>   f_;
+
+    public:
+        inline library_function(const boost::shared_ptr<shared_library>& lib, T* func_ptr) BOOST_NOEXCEPT
+            : f_(lib, func_ptr)
+        {}
+
+#if defined(BOOST_NO_CXX11_TRAILING_RESULT_TYPES) || defined(BOOST_NO_CXX11_DECLTYPE) || defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) || defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+        operator T*() const BOOST_NOEXCEPT {
+            return f_.get();
+        }
+#else
+
+        // Compilation error at this point means that imported function
+        // was called with unmatching parameters.
+        //
+        // Example:
+        // auto f = dll::import<void(int)>("function", "lib.so");
+        // f("Hello");  // error: invalid conversion from 'const char*' to 'int'
+        // f(1, 2);     // error: too many arguments to function
+        // f();         // error: too few arguments to function
+        template <class... Args>
+        inline auto operator()(Args&&... args) const
+            -> decltype( (*f_)(static_cast<Args&&>(args)...) )
+        {
+            return (*f_)(static_cast<Args&&>(args)...);
+        }
+#endif
+    };
+
+    template <class T, class = void>
+    struct import_type;
+
+    template <class T>
+    struct import_type<T, typename boost::disable_if<boost::is_object<T> >::type> {
+        typedef boost::dll::detail::library_function<T> base_type;
+
+#if defined(BOOST_NO_CXX11_TRAILING_RESULT_TYPES) || defined(BOOST_NO_CXX11_DECLTYPE) || defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) || defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+        typedef boost::function<T>                      type;
+#else
+        typedef boost::dll::detail::library_function<T> type;
+#endif
+    };
+
+    template <class T>
+    struct import_type<T, typename boost::enable_if<boost::is_object<T> >::type> {
+        typedef boost::shared_ptr<T> base_type;
+        typedef boost::shared_ptr<T> type;
+    };
+} // namespace detail
+
+
+#ifndef BOOST_DLL_DOXYGEN
+#   define BOOST_DLL_IMPORT_RESULT_TYPE inline typename boost::dll::detail::import_type<T>::type
+#endif
+
+
+/*!
+* Returns callable object or boost::shared_ptr<T> that holds the symbol imported
+* from the loaded library. Returned value refcounts usage
+* of the loaded shared library, so that it won't get unload until all copies of return value
+* are not destroyed.
+*
+* This call will succeed if call to \forcedlink{shared_library}`::has(const char* )`
+* function with the same symbol name returned `true`.
+*
+* For importing symbols by \b alias names use \forcedlink{import_alias} method.
+*
+* \b Examples:
+*
+* \code
+* boost::function<int(int)> f = import<int(int)>("test_lib.so", "integer_func_name");
+*
+* auto f_cpp11 = import<int(int)>("test_lib.so", "integer_func_name");
+* \endcode
+*
+* \code
+* boost::shared_ptr<int> i = import<int>("test_lib.so", "integer_name");
+* \endcode
+*
+* \b Template \b parameter \b T:    Type of the symbol that we are going to import. Must be explicitly specified.
+*
+* \param lib Path to shared library or shared library to load function from.
+* \param name Null-terminated C or C++ mangled name of the function to import. Can handle std::string, char*, const char*.
+* \param mode An mode that will be used on library load.
+*
+* \return callable object if T is a function type, or boost::shared_ptr<T> if T is an object type.
+*
+* \throw boost::system::system_error if symbol does not exist or if the DLL/DSO was not loaded.
+*       Overload that accepts path also throws std::bad_alloc in case of insufficient memory.
+*/
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(const boost::filesystem::path& lib, const char* name,
+    load_mode::type mode = load_mode::default_mode)
+{
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(lib, mode);
+    return type(p, boost::addressof(p->get<T>(name)));
+}
+
+//! \overload boost::dll::import(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(const boost::filesystem::path& lib, const std::string& name,
+    load_mode::type mode = load_mode::default_mode)
+{
+    return import<T>(lib, name.c_str(), mode);
+}
+
+//! \overload boost::dll::import(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(const shared_library& lib, const char* name) {
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(lib);
+    return type(p, boost::addressof(p->get<T>(name)));
+}
+
+//! \overload boost::dll::import(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(const shared_library& lib, const std::string& name) {
+    return import<T>(lib, name.c_str());
+}
+
+//! \overload boost::dll::import(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(BOOST_RV_REF(shared_library) lib, const char* name) {
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(
+        boost::move(lib)
+    );
+    return type(p, boost::addressof(p->get<T>(name)));
+}
+
+//! \overload boost::dll::import(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import(BOOST_RV_REF(shared_library) lib, const std::string& name) {
+    return import<T>(boost::move(lib), name.c_str());
+}
+
+
+
+
+/*!
+* Returns callable object or boost::shared_ptr<T> that holds the symbol imported
+* from the loaded library. Returned value refcounts usage
+* of the loaded shared library, so that it won't get unload until all copies of return value
+* are not destroyed.
+*
+* This call will succeed if call to \forcedlink{shared_library}`::has(const char* )`
+* function with the same symbol name returned `true`.
+*
+* For importing symbols by \b non \b alias names use \forcedlink{import} method.
+*
+* \b Examples:
+*
+* \code
+* boost::function<int(int)> f = import_alias<int(int)>("test_lib.so", "integer_func_alias_name");
+*
+* auto f_cpp11 = import_alias<int(int)>("test_lib.so", "integer_func_alias_name");
+* \endcode
+*
+* \code
+* boost::shared_ptr<int> i = import_alias<int>("test_lib.so", "integer_alias_name");
+* \endcode
+*
+* \code
+* \endcode
+*
+* \b Template \b parameter \b T:    Type of the symbol alias that we are going to import. Must be explicitly specified.
+*
+* \param lib Path to shared library or shared library to load function from.
+* \param name Null-terminated C or C++ mangled name of the function or variable to import. Can handle std::string, char*, const char*.
+* \param mode An mode that will be used on library load.
+*
+* \return callable object if T is a function type, or boost::shared_ptr<T> if T is an object type.
+*
+* \throw boost::system::system_error if symbol does not exist or if the DLL/DSO was not loaded.
+*       Overload that accepts path also throws std::bad_alloc in case of insufficient memory.
+*/
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(const boost::filesystem::path& lib, const char* name,
+    load_mode::type mode = load_mode::default_mode)
+{
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(lib, mode);
+    return type(p, p->get<T*>(name));
+}
+
+//! \overload boost::dll::import_alias(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(const boost::filesystem::path& lib, const std::string& name,
+    load_mode::type mode = load_mode::default_mode)
+{
+    return import_alias<T>(lib, name.c_str(), mode);
+}
+
+//! \overload boost::dll::import_alias(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(const shared_library& lib, const char* name) {
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(lib);
+    return type(p, p->get<T*>(name));
+}
+
+//! \overload boost::dll::import_alias(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(const shared_library& lib, const std::string& name) {
+    return import_alias<T>(lib, name.c_str());
+}
+
+//! \overload boost::dll::import_alias(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(BOOST_RV_REF(shared_library) lib, const char* name) {
+    typedef typename boost::dll::detail::import_type<T>::base_type type;
+
+    boost::shared_ptr<boost::dll::shared_library> p = boost::make_shared<boost::dll::shared_library>(
+        boost::move(lib)
+    );
+    return type(p, p->get<T*>(name));
+}
+
+//! \overload boost::dll::import_alias(const boost::filesystem::path& lib, const char* name, load_mode::type mode)
+template <class T>
+BOOST_DLL_IMPORT_RESULT_TYPE import_alias(BOOST_RV_REF(shared_library) lib, const std::string& name) {
+    return import_alias<T>(boost::move(lib), name.c_str());
+}
+
+#undef BOOST_DLL_IMPORT_RESULT_TYPE
+
+
+}} // boost::dll
+
+#endif // BOOST_DLL_IMPORT_HPP
+