plugin loading changes

include/plugin.h

@@ -55,7 +55,8 @@ extern plugin_globals_t g_plugin_globals;
 extern std::vector<plugin_t> g_plugins;
 
 const char* plugin_result_to_str(pluginres_t res);
-bool plugin_load(plugin_t& p, std::string file);
+// returns: -1 if failed to load and don't continue, 0 if failed to load and continue, 1 if loaded
+int plugin_load(plugin_t& p, std::string file);
 void plugin_unload(plugin_t& p);
 
 #endif // __QMM2_PLUGIN_H__

src/main.cpp

@@ -29,7 +29,7 @@ static void s_main_detect_env();
 static void s_main_load_config(bool quiet = false);
 static void s_main_detect_game(std::string cfg_game, bool is_GetGameAPI_mode);
 static bool s_main_load_mod(std::string cfg_mod);
-static void s_main_load_plugin(std::string plugin_path);
+static bool s_main_load_plugin(std::string plugin_path);
 static intptr_t s_main_handle_command_qmm(int arg_inc);
 static intptr_t s_main_route_vmmain(intptr_t cmd, intptr_t* args);
 static intptr_t s_main_route_syscall(intptr_t cmd, intptr_t* args);
@@ -347,8 +347,11 @@ C_DLLEXPORT intptr_t vmMain(intptr_t cmd, ...) {
 		// load plugins
 		LOG(QMM_LOG_INFO, "QMM") << "Attempting to load plugins\n";
 		for (auto plugin_path : cfg_get_array_str(g_cfg, "plugins")) {
-			LOG(QMM_LOG_INFO, "QMM") << fmt::format("Attempting to load plugin \"{}\"\n", plugin_path);
-			s_main_load_plugin(plugin_path);
+			LOG(QMM_LOG_INFO, "QMM") << fmt::format("Attempting to load plugin \"{}\"...\n", plugin_path);
+			if (s_main_load_plugin(plugin_path))
+				LOG(QMM_LOG_INFO, "QMM") << fmt::format("Plugin \"{}\" loaded\n", plugin_path);
+			else
+				LOG(QMM_LOG_INFO, "QMM") << fmt::format("Plugin \"{}\" not loaded\n", plugin_path);
 		}
 		LOG(QMM_LOG_NOTICE, "QMM") << fmt::format("Successfully loaded {} plugin(s)\n", g_plugins.size());
 
@@ -606,16 +609,16 @@ static bool s_main_load_mod(std::string cfg_mod) {
 
 
 // general code to find a plugin file to load
-static void s_main_load_plugin(std::string plugin_path) {
+static bool s_main_load_plugin(std::string plugin_path) {
 	plugin_t p;
 	// absolute path, just attempt to load it directly
 	if (!path_is_relative(plugin_path)) {
-		// if the plugin decides to cancel itself in QMM_Attach, then plugin_load returns success
-		// but we only want to only store the plugin if it really loaded
-		if (plugin_load(p, plugin_path) && p.dll) {
+		// plugin_load returns 0 if no plugin file was found, 1 if success, and -1 if file was found but failure
+		if (plugin_load(p, plugin_path) > 0) {
 			g_plugins.push_back(p);
+			return true;
 		}
-		return;
+		return false;
 	}
 	// relative path, try the following locations in order:
 	// "<qmmdir>/<plugin>"
@@ -627,14 +630,17 @@ static void s_main_load_plugin(std::string plugin_path) {
 		fmt::format("./{}/{}", g_gameinfo.moddir, plugin_path)
 	};
 	for (auto& try_path : try_paths) {
-		// if the plugin decides to cancel itself in QMM_Attach, then plugin_load returns success
-		// but we only want to only store the plugin if it really loaded
-		if (plugin_load(p, try_path)) {
-			if (p.dll)
-				g_plugins.push_back(p);
-			return;
+		// plugin_load returns 0 if no plugin file was found, 1 if success, and -1 if file was found but failure
+		int ret = plugin_load(p, try_path);
+		if (ret > 0) {
+			g_plugins.push_back(p);
+			return true;
 		}
+		if (ret < 0)
+			return false;
 	}
+
+	return false;
 }
 
 

src/plugin.cpp

@@ -92,7 +92,10 @@ const char* plugin_result_to_str(pluginres_t res) {
 }
 
 
-bool plugin_load(plugin_t& p, std::string file) {
+// returns: -1 if failed to load and don't continue, 0 if failed to load and continue, 1 if loaded
+int plugin_load(plugin_t& p, std::string file) {
+	int ret = 0;
+
 	// if this plugin_t somehow already has a dll pointer, wipe it first
 	if (p.dll)
 		plugin_unload(p);
@@ -106,9 +109,21 @@ bool plugin_load(plugin_t& p, std::string file) {
 	// if this DLL is the same as QMM, cancel
 	if ((void*)p.dll == g_gameinfo.qmm_module_ptr) {
 		LOG(QMM_LOG_ERROR, "QMM") << fmt::format("plugin_load(\"{}\"): DLL is actually QMM?\n", file);
+		// treat this failure specially. this is a valid DLL, but it is QMM
+		ret = -1;
 		goto fail;
 	}
 
+	// if this DLL is the same as another loaded plugin, cancel
+	for (plugin_t& t : g_plugins) {
+		if (p.dll == t.dll) {
+			LOG(QMM_LOG_ERROR, "QMM") << fmt::format("plugin_load(\"{}\"): DLL is already loaded as plugin\n", file);
+			// treat this failure specially. this is a valid plugin, but it is already loaded
+			ret = -1;
+			goto fail;
+		}
+	}
+
 	if (!(p.QMM_Query = (plugin_query)dlsym(p.dll, "QMM_Query"))) {
 		LOG(QMM_LOG_ERROR, "QMM") << fmt::format("plugin_load(\"{}\"): Unable to find \"QMM_Query\" function\n", file);
 		goto fail;
@@ -178,18 +193,18 @@ bool plugin_load(plugin_t& p, std::string file) {
 	// QMM_Attach(engine syscall, mod vmmain, pointer to plugin result int, table of plugin helper functions, table of plugin variables)
 	if (!(p.QMM_Attach(g_gameinfo.pfnsyscall, g_mod.pfnvmMain, &g_plugin_globals.plugin_result, &s_pluginfuncs, &s_pluginvars))) {
 		LOG(QMM_LOG_ERROR, "QMM") << fmt::format("plugin_load(\"{}\"): QMM_Attach() returned 0\n", file);
-		// treat this failure specially. since this is a valid plugin, but decided on its own that it shouldn't be loaded,
-		// we return "true" so that QMM will not try to load the plugin again on a different path
-		plugin_unload(p);
-		return true;
+		// treat this failure specially. this is a valid plugin, but it decided on its own that it shouldn't be loaded
+		ret = -1;
+		goto fail;
 	}
 
 	p.path = file;
-	return true;
+	ret = 1;
+	return ret;
 
 fail:
 	plugin_unload(p);
-	return false;
+	return ret;
 }