initial matador ng commit

source/core/utils/library.cpp

@@ -0,0 +1,77 @@
+#include "matador/utils/library.hpp"
+#include "matador/utils/os.hpp"
+
+#include <utility>
+
+namespace matador::utils {
+
+library::library(std::string lib)
+  : lib_(std::move(lib))
+{}
+
+library::~library()
+{
+  unload();
+}
+
+bool library::load()
+{
+    auto path = os::getenv("MATADOR_BACKENDS_PATH");
+#if defined(_MSC_VER) || defined(__MINGW32__)
+    auto cookie = AddDllDirectory(std::wstring(path.begin(), path.end()).c_str());
+    handle_ = LoadLibraryExA((lib_ + ".dll").c_str(), nullptr, LOAD_LIBRARY_SEARCH_DEFAULT_DIRS);
+    RemoveDllDirectory(cookie);
+#elif defined(__APPLE__)
+    handle_ = dlopen(std::string("lib" + lib_ + ".dylib").c_str(), RTLD_LAZY);
+#else
+  handle_ = dlopen((path + "/lib" + lib_ + ".so").c_str(), RTLD_LAZY);
+#endif
+    if (!handle_) {
+#if defined(_MSC_VER) || defined(__MINGW32__)
+        DWORD errorMessageID = ::GetLastError();
+        auto errstr = utils::os::error_string(errorMessageID);
+#else
+        // TODO: handle win32 and linux error
+    fprintf(stdout, "dlopen error: %s", dlerror());
+#endif
+        return false;
+    }
+    return true;
+}
+
+bool library::load(const std::string &lib)
+{
+  if (handle_) {
+    return false;
+  }
+  lib_ = lib;
+  return load();
+}
+
+bool library::unload()
+{
+  bool ret(true);
+  if (handle_) {
+#if defined(_MSC_VER) || defined(__MINGW32__)
+    ret = FreeLibrary(handle_) == TRUE;
+#else
+    ret = dlclose(handle_) == 0;
+#endif
+    if (!ret) {
+    } else {
+      handle_ = nullptr;
+    }
+  }
+  return ret;
+}
+
+func_ptr library::function(const std::string &f) const
+{
+#if defined(_MSC_VER) || defined(__MINGW32__)
+  return GetProcAddress(handle_, f.c_str());
+#else
+  return dlsym(handle_, f.c_str());
+#endif
+}
+
+}