main.cpp

int g_my_action_id1 = 0;

// the callback should handle all the actions handled by this single plugin
// so, don't add new callback functions separately for each action!

bool hookCommandProc(int command, int flag)
{
	if (command != 0 && command == g_my_action_id1)
	{
		ShowConsoleMsg("Extension test action executed.\n");
		return true; // action was found and handled
	}
	return false; // action not handled by this plugin
}

extern "C"
{
	REAPER_PLUGIN_DLL_EXPORT int REAPER_PLUGIN_ENTRYPOINT(REAPER_PLUGIN_HINSTANCE hInstance, reaper_plugin_info_t *rec)
	{
		if (rec != nullptr)
		{
			// Load the ShowConsoleMsg API function to be able to do something marginally interesting in the action implementation code
			// Every API function must be separately loaded!
			// In C or C++, the ShowConsoleMsg declaration and function pointer are already available
			// I guess In Rust, you have to separately add the function pointers for the API functions as global variables 
			((*(void **)&(ShowConsoleMsg)) = (void *)rec->GetFunc("ShowConsoleMsg"));
			// register new command ID
			g_my_action_id1 = rec->Register("command_id", (void*)"FOOTEST_ACTION_ID1");
			// but not enough, must also register accel for keyboard shortcut and command description for action
			// list window 
			// gaccel_register_t is declared in reaper_plugin.h
			// the ACCEL accel field is a Windows type
			gaccel_register_t accel_reg;
			accel_reg.accel = { 0,0,0 }; // means, no shortcut key assigned by default
			accel_reg.desc = "Xenakios : Extension action example";
			accel_reg.accel.cmd = g_my_action_id1;
			rec->Register("gaccel", (void*)&accel_reg);
			rec->Register("hookcommand", (void*)hookCommandProc);
			return 1; // plugin succesfully loaded, return 0 here if could not initialize properly
		}
		else
		{
			// plugin is being unloaded when Reaper quits
			ShowConsoleMsg("Unloading extension plugin\n"); // you will never get to see this message, though...
			return 0;
		}
	}
}