Fix various copy instead of const ref reported by cppcheck (part 3) (#5616)

* Also remove 2 non declared but defined functions
* Make some functions around const ref changes const

4 files changed, 23 insertions, 12 deletions

diff --git a/src/script/cpp_api/s_async.cpp b/src/script/cpp_api/s_async.cpp
index 1fb84fab6..a1bec83bf 100644
--- a/src/script/cpp_api/s_async.cpp
+++ b/src/script/cpp_api/s_async.cpp
@@ -100,7 +100,8 @@ void AsyncEngine::initialize(unsigned int numEngines)
 }
 
 /******************************************************************************/
-unsigned int AsyncEngine::queueAsyncJob(std::string func, std::string params)
+unsigned int AsyncEngine::queueAsyncJob(const std::string &func,
+		const std::string &params)
 {
 	jobQueueMutex.lock();
 	LuaJobInfo toAdd;
@@ -124,7 +125,6 @@ LuaJobInfo AsyncEngine::getJob()
 	jobQueueMutex.lock();
 
 	LuaJobInfo retval;
-	retval.valid = false;
 
 	if (!jobQueue.empty()) {
 		retval = jobQueue.front();
@@ -137,7 +137,7 @@ LuaJobInfo AsyncEngine::getJob()
 }
 
 /******************************************************************************/
-void AsyncEngine::putJobResult(LuaJobInfo result)
+void AsyncEngine::putJobResult(const LuaJobInfo &result)
 {
 	resultQueueMutex.lock();
 	resultQueue.push_back(result);
@@ -264,7 +264,7 @@ void* AsyncWorkerThread::run()
 		// Wait for job
 		LuaJobInfo toProcess = jobDispatcher->getJob();
 
-		if (toProcess.valid == false || stopRequested()) {
+		if (!toProcess.valid || stopRequested()) {
 			continue;
 		}
 
diff --git a/src/script/cpp_api/s_async.h b/src/script/cpp_api/s_async.h
index 016381e5f..93e9759b4 100644
--- a/src/script/cpp_api/s_async.h
+++ b/src/script/cpp_api/s_async.h
@@ -38,7 +38,16 @@ class AsyncEngine;
 // Declarations
 
 // Data required to queue a job
-struct LuaJobInfo {
+struct LuaJobInfo
+{
+	LuaJobInfo() :
+		serializedFunction(""),
+		serializedParams(""),
+		serializedResult(""),
+		id(0),
+		valid(false)
+	{}
+
 	// Function to be called in async environment
 	std::string serializedFunction;
 	// Parameter to be passed to function
@@ -89,7 +98,7 @@ public:
 	 * @param params Serialized parameters
 	 * @return jobid The job is queued
 	 */
-	unsigned int queueAsyncJob(std::string func, std::string params);
+	unsigned int queueAsyncJob(const std::string &func, const std::string &params);
 
 	/**
 	 * Engine step to process finished jobs
@@ -116,7 +125,7 @@ protected:
 	 * Put a Job result back to result queue
 	 * @param result result of completed job
 	 */
-	void putJobResult(LuaJobInfo result);
+	void putJobResult(const LuaJobInfo &result);
 
 	/**
 	 * Initialize environment with current registred functions
diff --git a/src/script/scripting_mainmenu.cpp b/src/script/scripting_mainmenu.cpp
index 61318735d..d79864a95 100644
--- a/src/script/scripting_mainmenu.cpp
+++ b/src/script/scripting_mainmenu.cpp
@@ -77,13 +77,15 @@ void MainMenuScripting::initializeModApi(lua_State *L, int top)
 }
 
 /******************************************************************************/
-void MainMenuScripting::step() {
+void MainMenuScripting::step()
+{
 	asyncEngine.step(getStack());
 }
 
 /******************************************************************************/
-unsigned int MainMenuScripting::queueAsync(std::string serialized_func,
-		std::string serialized_param) {
+unsigned int MainMenuScripting::queueAsync(const std::string &serialized_func,
+		const std::string &serialized_param)
+{
 	return asyncEngine.queueAsyncJob(serialized_func, serialized_param);
 }
 
diff --git a/src/script/scripting_mainmenu.h b/src/script/scripting_mainmenu.h
index 3a0795df4..a1385ba9c 100644
--- a/src/script/scripting_mainmenu.h
+++ b/src/script/scripting_mainmenu.h
@@ -39,8 +39,8 @@ public:
 	void step();
 
 	// Pass async events from engine to async threads
-	unsigned int queueAsync(std::string serialized_func,
-			std::string serialized_params);
+	unsigned int queueAsync(const std::string &serialized_func,
+			const std::string &serialized_params);
 private:
 	void initializeModApi(lua_State *L, int top);