Exact stack rooting for JSON related ScriptInterface functions.

Refs #2415
Refs #2462

This was SVN commit r15603.

source/graphics/MapGenerator.cpp

@@ -108,7 +108,8 @@ bool CMapGeneratorWorker::Run()
 	m_ScriptInterface->RegisterFunction<std::vector<std::string>, std::string, bool, CMapGeneratorWorker::FindActorTemplates>("FindActorTemplates");
 
 	// Parse settings
-	JS::RootedValue settingsVal(cx, m_ScriptInterface->ParseJSON(m_Settings).get());
+	JS::RootedValue settingsVal(cx);
+	m_ScriptInterface->ParseJSON(m_Settings, &settingsVal);
 	if (settingsVal.isUndefined())
 	{
 		LOGERROR(L"CMapGeneratorWorker::Run: Failed to parse settings");

source/graphics/MapReader.cpp

@@ -392,7 +392,11 @@ CScriptValRooted CMapSummaryReader::GetMapSettings(ScriptInterface& scriptInterf
 	JS::RootedValue data(cx);
 	scriptInterface.Eval("({})", &data);
 	if (!m_ScriptSettings.empty())
-		scriptInterface.SetProperty(data, "settings", scriptInterface.ParseJSON(m_ScriptSettings), false);
+	{
+		JS::RootedValue scriptSettingsVal(cx);
+		scriptInterface.ParseJSON(m_ScriptSettings, &scriptSettingsVal);
+		scriptInterface.SetProperty(data, "settings", scriptSettingsVal, false);
+	}
 	return CScriptValRooted(cx, data);
 }
 
@@ -1269,8 +1273,10 @@ int CMapReader::GenerateMap()
 		if (m_ScriptFile.length())
 			scriptPath = L"maps/random/"+m_ScriptFile;
 
+		// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+		JS::RootedValue tmpScriptSettings(cx, m_ScriptSettings.get());
 		// Stringify settings to pass across threads
-		std::string scriptSettings = pSimulation2->GetScriptInterface().StringifyJSON(m_ScriptSettings.get());
+		std::string scriptSettings = pSimulation2->GetScriptInterface().StringifyJSON(&tmpScriptSettings);
 		
 		// Try to generate map
 		m_MapGen->GenerateMap(scriptPath, scriptSettings);

source/gui/GUIManager.cpp

@@ -294,7 +294,7 @@ std::string CGUIManager::GetSavedGameData()
 	JS::RootedValue data(cx);
 	JS::RootedValue global(cx, top()->GetGlobalObject());
 	scriptInterface->CallFunction(global, "getSavedGameData", &data);
-	return scriptInterface->StringifyJSON(data, false);
+	return scriptInterface->StringifyJSON(&data, false);
 }
 
 void CGUIManager::RestoreSavedGameData(std::string jsonData)
@@ -304,7 +304,9 @@ void CGUIManager::RestoreSavedGameData(std::string jsonData)
 	JSAutoRequest rq(cx);
 	
 	JS::RootedValue global(cx, top()->GetGlobalObject());
-	scriptInterface->CallFunctionVoid(global, "restoreSavedGameData", scriptInterface->ParseJSON(jsonData));
+	JS::RootedValue dataVal(cx);
+	scriptInterface->ParseJSON(jsonData, &dataVal);
+	scriptInterface->CallFunctionVoid(global, "restoreSavedGameData", dataVal);
 }
 
 InReaction CGUIManager::HandleEvent(const SDL_Event_* ev)

source/gui/scripting/ScriptFunctions.cpp

@@ -298,11 +298,15 @@ void SaveGamePrefix(ScriptInterface::CxPrivate* pCxPrivate, std::wstring prefix,
 		LOGERROR(L"Failed to save game");
 }
 
-void SetNetworkGameAttributes(ScriptInterface::CxPrivate* pCxPrivate, CScriptVal attribs)
+void SetNetworkGameAttributes(ScriptInterface::CxPrivate* pCxPrivate, CScriptVal attribs1)
 {
 	ENSURE(g_NetServer);
+	// TODO: Get Handle parameter directly with SpiderMonkey 31
+	JSContext* cx = pCxPrivate->pScriptInterface->GetContext();
+	JSAutoRequest rq(cx);
+	JS::RootedValue attribs(cx, attribs1.get());
 
-	g_NetServer->UpdateGameAttributes(attribs, *(pCxPrivate->pScriptInterface));
+	g_NetServer->UpdateGameAttributes(&attribs, *(pCxPrivate->pScriptInterface));
 }
 
 void StartNetworkHost(ScriptInterface::CxPrivate* pCxPrivate, std::wstring playerName)

source/main.cpp

@@ -190,7 +190,7 @@ static void PumpEvents()
 		{
 			JS::RootedValue tmpVal(cx);
 			ScriptInterface::ToJSVal(cx, &tmpVal, ev);
-			std::string data = g_GUI->GetScriptInterface()->StringifyJSON(tmpVal);
+			std::string data = g_GUI->GetScriptInterface()->StringifyJSON(&tmpVal);
 			PROFILE2_ATTR("%s", data.c_str());
 		}
 		in_dispatch_event(&ev);

source/network/NetServer.cpp

@@ -375,6 +375,9 @@ bool CNetServerWorker::RunStep()
 	// Check for messages from the game thread.
 	// (Do as little work as possible while the mutex is held open,
 	// to avoid performance problems and deadlocks.)
+	
+	JSContext* cx = m_ScriptInterface->GetContext();
+	JSAutoRequest rq(cx);
 
 	std::vector<std::pair<int, CStr> > newAssignPlayer;
 	std::vector<bool> newStartGame;
@@ -407,7 +410,11 @@ bool CNetServerWorker::RunStep()
 		ClearAllPlayerReady();
 
 	if (!newGameAttributes.empty())
-		UpdateGameAttributes(GetScriptInterface().ParseJSON(newGameAttributes.back()));
+	{
+		JS::RootedValue gameAttributesVal(cx);
+		GetScriptInterface().ParseJSON(newGameAttributes.back(), &gameAttributesVal);
+		UpdateGameAttributes(&gameAttributesVal);
+	}
 
 	if (!newTurnLength.empty())
 		SetTurnLength(newTurnLength.back());
@@ -997,17 +1004,21 @@ void CNetServerWorker::StartGame()
 
 	m_State = SERVER_STATE_LOADING;
 
+	JSContext* cx = GetScriptInterface().GetContext();
+	JSAutoRequest rq(cx);
+	// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+	JS::RootedValue tmpGameAttributes(cx, m_GameAttributes.get());
 	// Send the final setup state to all clients
-	UpdateGameAttributes(m_GameAttributes);
+	UpdateGameAttributes(&tmpGameAttributes);
 	SendPlayerAssignments();
 
 	CGameStartMessage gameStart;
 	Broadcast(&gameStart);
 }
 
-void CNetServerWorker::UpdateGameAttributes(const CScriptValRooted& attrs)
+void CNetServerWorker::UpdateGameAttributes(JS::MutableHandleValue attrs)
 {
-	m_GameAttributes = attrs;
+	m_GameAttributes = CScriptValRooted(GetScriptInterface().GetContext(), attrs);
 
 	if (!m_Host)
 		return;
@@ -1106,11 +1117,11 @@ void CNetServer::StartGame()
 	m_Worker->m_StartGameQueue.push_back(true);
 }
 
-void CNetServer::UpdateGameAttributes(const CScriptVal& attrs, ScriptInterface& scriptInterface)
+void CNetServer::UpdateGameAttributes(JS::MutableHandleValue attrs, ScriptInterface& scriptInterface)
 {
 	// Pass the attributes as JSON, since that's the easiest safe
 	// cross-thread way of passing script data
-	std::string attrsJSON = scriptInterface.StringifyJSON(attrs.get(), false);
+	std::string attrsJSON = scriptInterface.StringifyJSON(attrs, false);
 
 	CScopeLock lock(m_Worker->m_WorkerMutex);
 	m_Worker->m_GameAttributesQueue.push_back(attrsJSON);

source/network/NetServer.h

@@ -146,7 +146,7 @@ public:
 	 * The changes will be asynchronously propagated to all clients.
 	 * @param attrs game attributes, in the script context of scriptInterface
 	 */
-	void UpdateGameAttributes(const CScriptVal& attrs, ScriptInterface& scriptInterface);
+	void UpdateGameAttributes(JS::MutableHandleValue attrs, ScriptInterface& scriptInterface);
 
 	/**
 	 * Set the turn length to a fixed value.
@@ -220,7 +220,7 @@ private:
 	 * The changes will be propagated to all clients.
 	 * @param attrs game attributes, in the script context of GetScriptInterface()
 	 */
-	void UpdateGameAttributes(const CScriptValRooted& attrs);
+	void UpdateGameAttributes(JS::MutableHandleValue attrs);
 
 	/**
 	 * Make a player name 'nicer' by limiting the length and removing forbidden characters etc.

source/network/tests/test_Net.h

@@ -135,6 +135,9 @@ public:
 		// and prints a load of debug output so you can see if anything funny's going on
 
 		ScriptInterface scriptInterface("Engine", "Test", g_ScriptRuntime);
+		JSContext* cx = scriptInterface.GetContext();
+		JSAutoRequest rq(cx);
+		
 		TestStdoutLogger logger;
 
 		std::vector<CNetClient*> clients;
@@ -145,9 +148,9 @@ public:
 
 		CNetServer server;
 
-		CScriptValRooted attrs;
-		scriptInterface.Eval("({mapType:'scenario',map:'_default',thing:'example'})", attrs);
-		server.UpdateGameAttributes(attrs.get(), scriptInterface);
+		JS::RootedValue attrs(cx);
+		scriptInterface.Eval("({mapType:'scenario',map:'_default',thing:'example'})", &attrs);
+		server.UpdateGameAttributes(&attrs, scriptInterface);
 
 		CNetClient client1(&client1Game);
 		CNetClient client2(&client2Game);
@@ -197,6 +200,9 @@ public:
 	void test_rejoin_DISABLED()
 	{
 		ScriptInterface scriptInterface("Engine", "Test", g_ScriptRuntime);
+		JSContext* cx = scriptInterface.GetContext();
+		JSAutoRequest rq(cx);
+		
 		TestStdoutLogger logger;
 
 		std::vector<CNetClient*> clients;
@@ -207,9 +213,9 @@ public:
 
 		CNetServer server;
 
-		CScriptValRooted attrs;
-		scriptInterface.Eval("({mapType:'scenario',map:'_default',thing:'example'})", attrs);
-		server.UpdateGameAttributes(attrs.get(), scriptInterface);
+		JS::RootedValue attrs(cx);
+		scriptInterface.Eval("({mapType:'scenario',map:'_default',thing:'example'})", &attrs);
+		server.UpdateGameAttributes(&attrs, scriptInterface);
 
 		CNetClient client1(&client1Game);
 		CNetClient client2(&client2Game);

source/ps/Game.cpp

@@ -282,7 +282,7 @@ void CGame::StartGame(const CScriptValRooted& attribs1, const std::string& saved
 	JSAutoRequest rq(cx);
 	
 	JS::RootedValue attribs(cx, attribs1.get()); // TODO: Get Handle parameter directly with SpiderMonkey 31
-	m_ReplayLogger->StartGame(attribs1);
+	m_ReplayLogger->StartGame(&attribs);
 
 	RegisterInit(attribs, savedState);
 }

source/ps/GameSetup/GameSetup.cpp

@@ -1184,7 +1184,8 @@ bool Autostart(const CmdLineArgs& args)
 		
 		// Random map definition will be loaded from JSON file, so we need to parse it
 		std::wstring scriptPath = L"maps/" + autoStartName.FromUTF8() + L".json";
-		JS::RootedValue scriptData(cx, scriptInterface.ReadJSONFile(scriptPath).get());
+		JS::RootedValue scriptData(cx);
+		scriptInterface.ReadJSONFile(scriptPath, &scriptData);
 		if (!scriptData.isUndefined() && scriptInterface.GetProperty(scriptData, "settings", &settings))
 		{
 			// JSON loaded ok - copy script name over to game attributes
@@ -1239,9 +1240,7 @@ bool Autostart(const CmdLineArgs& args)
 		// (Omitting this may cause the loading screen to display "Loading (undefined)",
 		// for example...)
 		CStr8 mapSettingsJSON = LoadSettingsOfScenarioMap("maps/" + autoStartName + ".xml");
-		CScriptValRooted mapSettings = scriptInterface.ParseJSON(mapSettingsJSON);
-
-		settings = mapSettings.get();
+		scriptInterface.ParseJSON(mapSettingsJSON, &settings);
 		mapType = "scenario";
 	}
 	else if (mapDirectory == L"skirmishes")
@@ -1253,9 +1252,8 @@ bool Autostart(const CmdLineArgs& args)
 		// To prevent this, we mimic the behavior of the game setup screen by
 		// retrieving the map settings from the actual map xml...
 		CStr8 mapSettingsJSON = LoadSettingsOfScenarioMap("maps/" + autoStartName + ".xml");
-		CScriptValRooted mapSettings = scriptInterface.ParseJSON(mapSettingsJSON);
-
-		settings = mapSettings.get();
+		scriptInterface.ParseJSON(mapSettingsJSON, &settings);
+		
 		// ...and initialize the playerData array being edited by
 		// autostart-civ et.al. with the real map data, so sensible values
 		// are always present:
@@ -1364,7 +1362,7 @@ bool Autostart(const CmdLineArgs& args)
 
 		g_NetServer = new CNetServer(maxPlayers);
 
-		g_NetServer->UpdateGameAttributes(attrs.get(), scriptInterface);
+		g_NetServer->UpdateGameAttributes(&attrs, scriptInterface);
 
 		bool ok = g_NetServer->SetupConnection();
 		ENSURE(ok);

source/ps/GameSetup/HWDetect.cpp

@@ -320,7 +320,7 @@ void RunHardwareDetection()
 	scriptInterface.SetProperty(settings, "timer_resolution", timer_Resolution());
 
 	// Send the same data to the reporting system
-	g_UserReporter.SubmitReport("hwdetect", 11, scriptInterface.StringifyJSON(settings, false));
+	g_UserReporter.SubmitReport("hwdetect", 11, scriptInterface.StringifyJSON(&settings, false));
 
 	// Run the detection script:
 	JS::RootedValue global(cx, scriptInterface.GetGlobalObject());

source/ps/Replay.cpp

@@ -75,17 +75,22 @@ CReplayLogger::~CReplayLogger()
 	delete m_Stream;
 }
 
-void CReplayLogger::StartGame(const CScriptValRooted& attribs)
+void CReplayLogger::StartGame(JS::MutableHandleValue attribs)
 {
-	*m_Stream << "start " << m_ScriptInterface.StringifyJSON(attribs.get(), false) << "\n";
+	*m_Stream << "start " << m_ScriptInterface.StringifyJSON(attribs, false) << "\n";
 }
 
 void CReplayLogger::Turn(u32 n, u32 turnLength, const std::vector<SimulationCommand>& commands)
 {
+	JSContext* cx = m_ScriptInterface.GetContext();
+	JSAutoRequest rq(cx);
+	
 	*m_Stream << "turn " << n << " " << turnLength << "\n";
 	for (size_t i = 0; i < commands.size(); ++i)
 	{
-		*m_Stream << "cmd " << commands[i].player << " " << m_ScriptInterface.StringifyJSON(commands[i].data.get(), false) << "\n";
+		// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+		JS::RootedValue tmpCommand(cx, commands[i].data.get());
+		*m_Stream << "cmd " << commands[i].player << " " << m_ScriptInterface.StringifyJSON(&tmpCommand, false) << "\n";
 	}
 	*m_Stream << "end\n";
 	m_Stream->flush();
@@ -133,6 +138,9 @@ void CReplayPlayer::Replay(bool serializationtest)
 	g_Game = &game;
 	if (serializationtest)
 		game.GetSimulation2()->EnableSerializationTest();
+		
+	JSContext* cx = game.GetSimulation2()->GetScriptInterface().GetContext();
+	JSAutoRequest rq(cx);
 
 	// Need some stuff for terrain movement costs:
 	// (TODO: this ought to be independent of any graphics code)
@@ -155,9 +163,10 @@ void CReplayPlayer::Replay(bool serializationtest)
 		{
 			std::string line;
 			std::getline(*m_Stream, line);
-			CScriptValRooted attribs = game.GetSimulation2()->GetScriptInterface().ParseJSON(line);
+			JS::RootedValue attribs(cx);
+			game.GetSimulation2()->GetScriptInterface().ParseJSON(line, &attribs);
 
-			game.StartGame(attribs, "");
+			game.StartGame(CScriptValRooted(cx, attribs), "");
 
 			// TODO: Non progressive load can fail - need a decent way to handle this
 			LDR_NonprogressiveLoad();
@@ -177,9 +186,10 @@ void CReplayPlayer::Replay(bool serializationtest)
 
 			std::string line;
 			std::getline(*m_Stream, line);
-			CScriptValRooted data = game.GetSimulation2()->GetScriptInterface().ParseJSON(line);
+			JS::RootedValue data(cx);
+			game.GetSimulation2()->GetScriptInterface().ParseJSON(line, &data);
 
-			SimulationCommand cmd = { player, data };
+			SimulationCommand cmd = { player, CScriptValRooted(cx, data) };
 			commands.push_back(cmd);
 		}
 		else if (type == "hash" || type == "hash-quick")

source/ps/Replay.h

@@ -18,6 +18,8 @@
 #ifndef INCLUDED_REPLAY
 #define INCLUDED_REPLAY
 
+#include "scriptinterface/ScriptTypes.h"
+
 class CScriptValRooted;
 struct SimulationCommand;
 class ScriptInterface;
@@ -35,7 +37,7 @@ public:
 	/**
 	 * Started the game with the given game attributes.
 	 */
-	virtual void StartGame(const CScriptValRooted& attribs) = 0;
+	virtual void StartGame(JS::MutableHandleValue attribs) = 0;
 
 	/**
 	 * Run the given turn with the given collection of player commands.
@@ -69,7 +71,7 @@ public:
 	CReplayLogger(ScriptInterface& scriptInterface);
 	~CReplayLogger();
 
-	virtual void StartGame(const CScriptValRooted& attribs);
+	virtual void StartGame(JS::MutableHandleValue attribs);
 	virtual void Turn(u32 n, u32 turnLength, const std::vector<SimulationCommand>& commands);
 	virtual void Hash(const std::string& hash, bool quick);
 

source/ps/SavedGame.cpp

@@ -106,7 +106,7 @@ Status SavedGames::Save(const std::wstring& name, const std::wstring& descriptio
 	
 	simulation.GetScriptInterface().SetProperty(metadata, "description", description);
 	
-	std::string metadataString = simulation.GetScriptInterface().StringifyJSON(metadata, true);
+	std::string metadataString = simulation.GetScriptInterface().StringifyJSON(&metadata, true);
 	
 	// Write the saved game as zip file containing the various components
 	PIArchiveWriter archiveWriter = CreateArchiveWriter_Zip(tempSaveFileRealPath, false);
@@ -161,12 +161,17 @@ public:
 
 	void ReadEntry(const VfsPath& pathname, const CFileInfo& fileInfo, PIArchiveFile archiveFile)
 	{
+		JSContext* cx = m_ScriptInterface.GetContext();
+		JSAutoRequest rq(cx);
+		
 		if (pathname == L"metadata.json")
 		{
 			std::string buffer;
 			buffer.resize(fileInfo.Size());
 			WARN_IF_ERR(archiveFile->Load("", DummySharedPtr((u8*)buffer.data()), buffer.size()));
-			m_Metadata = m_ScriptInterface.ParseJSON(buffer);
+			JS::RootedValue tmpMetadata(cx); // TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+			m_ScriptInterface.ParseJSON(buffer, &tmpMetadata);
+			m_Metadata = CScriptValRooted(cx, tmpMetadata);
 		}
 		else if (pathname == L"simulation.dat" && m_SavedState)
 		{

source/ps/TemplateLoader.cpp

@@ -203,7 +203,8 @@ std::vector<std::string> CTemplateLoader::FindPlaceableTemplates(const std::stri
 
 	if (templatesType == SIMULATION_TEMPLATES || templatesType == ALL_TEMPLATES)
 	{
-		JS::RootedValue placeablesFilter(cx, scriptInterface.ReadJSONFile("simulation/data/placeablesFilter.json").get());
+		JS::RootedValue placeablesFilter(cx);
+		scriptInterface.ReadJSONFile("simulation/data/placeablesFilter.json", &placeablesFilter);
 		
 		std::vector<CScriptValRooted> folders;
 		if (scriptInterface.GetProperty(placeablesFilter, "templates", folders))

source/scriptinterface/ScriptInterface.cpp

@@ -1238,23 +1238,24 @@ bool ScriptInterface::Eval_(const wchar_t* code, JS::MutableHandleValue rval)
 	return ok;
 }
 
-CScriptValRooted ScriptInterface::ParseJSON(const std::string& string_utf8)
+void ScriptInterface::ParseJSON(const std::string& string_utf8, JS::MutableHandleValue out)
 {
 	JSAutoRequest rq(m->m_cx);
 	std::wstring attrsW = wstring_from_utf8(string_utf8);
  	utf16string string(attrsW.begin(), attrsW.end());
-	JS::RootedValue vp(m->m_cx);
-	if (!JS_ParseJSON(m->m_cx, reinterpret_cast<const jschar*>(string.c_str()), (u32)string.size(), &vp))
+	if (!JS_ParseJSON(m->m_cx, reinterpret_cast<const jschar*>(string.c_str()), (u32)string.size(), out))
+	{
 		LOGERROR(L"JS_ParseJSON failed!");
-	return CScriptValRooted(m->m_cx, vp);
+		return;
+	}
 }
 
-CScriptValRooted ScriptInterface::ReadJSONFile(const VfsPath& path)
+void ScriptInterface::ReadJSONFile(const VfsPath& path, JS::MutableHandleValue out)
 {
 	if (!VfsFileExists(path))
 	{
 		LOGERROR(L"File '%ls' does not exist", path.string().c_str());
-		return CScriptValRooted();
+		return;
 	}
 
 	CVFSFile file;
@@ -1264,12 +1265,12 @@ CScriptValRooted ScriptInterface::ReadJSONFile(const VfsPath& path)
 	if (ret != PSRETURN_OK)
 	{
 		LOGERROR(L"Failed to load file '%ls': %hs", path.string().c_str(), GetErrorString(ret));
-		return CScriptValRooted();
+		return;
 	}
 
 	std::string content(file.DecodeUTF8()); // assume it's UTF-8
 
-	return ParseJSON(content);
+	ParseJSON(content, out);
 }
 
 struct Stringifier
@@ -1299,11 +1300,14 @@ struct StringifierW
 	std::wstringstream stream;
 };
 
-std::string ScriptInterface::StringifyJSON(jsval obj, bool indent)
+// TODO: It's not quite clear why JS_Stringify needs JS::MutableHandleValue. |obj| should not get modified.
+// It probably has historical reasons and could be changed by SpiderMonkey in the future.
+std::string ScriptInterface::StringifyJSON(JS::MutableHandleValue obj, bool indent)
 {
 	JSAutoRequest rq(m->m_cx);
 	Stringifier str;
-	if (!JS_Stringify(m->m_cx, &obj, NULL, indent ? INT_TO_JSVAL(2) : JSVAL_VOID, &Stringifier::callback, &str))
+	JS::RootedValue indentVal(m->m_cx, indent ? JS::Int32Value(2) : JS::UndefinedValue());
+	if (!JS_Stringify(m->m_cx, obj.address(), NULL, indentVal, &Stringifier::callback, &str))
 	{
 		JS_ClearPendingException(m->m_cx);
 		LOGERROR(L"StringifyJSON failed");

source/scriptinterface/ScriptInterface.h

@@ -268,19 +268,19 @@ public:
 	std::wstring ToString(jsval obj, bool pretty = false);
 
 	/**
-	 * Parse a UTF-8-encoded JSON string. Returns the undefined value on error.
+	 * Parse a UTF-8-encoded JSON string. Returns the unmodified value on error and prints an error message.
 	 */
-	CScriptValRooted ParseJSON(const std::string& string_utf8);
+	void ParseJSON(const std::string& string_utf8, JS::MutableHandleValue out);
 
 	/**
-	 * Read a JSON file. Returns the undefined value on error.
+	 * Read a JSON file. Returns the unmodified value on error and prints an error message.
 	 */
-	CScriptValRooted ReadJSONFile(const VfsPath& path);
+	void ReadJSONFile(const VfsPath& path, JS::MutableHandleValue out);
 
 	/**
 	 * Stringify to a JSON string, UTF-8 encoded. Returns an empty string on error.
 	 */
-	std::string StringifyJSON(jsval obj, bool indent = true);
+	std::string StringifyJSON(JS::MutableHandleValue obj, bool indent = true);
 	
 	/**
 	 * Report the given error message through the JS error reporting mechanism,

source/scriptinterface/tests/test_ScriptInterface.h

@@ -241,15 +241,17 @@ public:
 	void test_json()
 	{
 		ScriptInterface script("Test", "Test", g_ScriptRuntime);
+		JSContext* cx = script.GetContext();
+		JSAutoRequest rq(cx);
 
 		std::string input = "({'x':1,'z':[2,'3\\u263A\\ud800'],\"y\":true})";
-		CScriptValRooted val;
-		TS_ASSERT(script.Eval(input.c_str(), val));
+		JS::RootedValue val(cx);
+		TS_ASSERT(script.Eval(input.c_str(), &val));
 
-		std::string stringified = script.StringifyJSON(val.get());
+		std::string stringified = script.StringifyJSON(&val);
 		TS_ASSERT_STR_EQUALS(stringified, "{\n  \"x\": 1,\n  \"z\": [\n    2,\n    \"3\xE2\x98\xBA\xEF\xBF\xBD\"\n  ],\n  \"y\": true\n}");
 
-		val = script.ParseJSON(stringified);
+		script.ParseJSON(stringified, &val);
 		TS_ASSERT_WSTR_EQUALS(script.ToString(val.get()), L"({x:1, z:[2, \"3\\u263A\\uFFFD\"], y:true})");
 	}
 };

source/simulation2/Simulation2.cpp

@@ -724,7 +724,12 @@ CScriptValRooted CSimulation2::GetInitAttributes()
 
 void CSimulation2::SetMapSettings(const std::string& settings)
 {
-	m->m_MapSettings = m->m_ComponentManager.GetScriptInterface().ParseJSON(settings);
+	JSContext* cx = m->m_ComponentManager.GetScriptInterface().GetContext();
+	JSAutoRequest rq(cx);
+	// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+	JS::RootedValue tmpMapSettings(cx);
+	m->m_ComponentManager.GetScriptInterface().ParseJSON(settings, &tmpMapSettings);
+	m->m_MapSettings = CScriptValRooted(cx, tmpMapSettings); 
 }
 
 void CSimulation2::SetMapSettings(const CScriptValRooted& settings)
@@ -734,7 +739,11 @@ void CSimulation2::SetMapSettings(const CScriptValRooted& settings)
 
 std::string CSimulation2::GetMapSettingsString()
 {
-	return m->m_ComponentManager.GetScriptInterface().StringifyJSON(m->m_MapSettings.get());
+	JSContext* cx = m->m_ComponentManager.GetScriptInterface().GetContext();
+	JSAutoRequest rq(cx);
+	// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+	JS::RootedValue tmpMapSettings(cx, m->m_MapSettings.get());
+	return m->m_ComponentManager.GetScriptInterface().StringifyJSON(&tmpMapSettings);
 }
 
 CScriptVal CSimulation2::GetMapSettings()
@@ -929,5 +938,5 @@ std::string CSimulation2::GetAIData()
 	if (!scriptInterface.Eval("({})", &ais) || !scriptInterface.SetProperty(ais, "AIData", aiData))
 		return std::string();
 	
-	return scriptInterface.StringifyJSON(ais);
+	return scriptInterface.StringifyJSON(&ais);
 }

source/simulation2/components/CCmpAIManager.cpp

@@ -100,7 +100,8 @@ private:
 			JSAutoRequest rq(cx);
 
 			OsPath path = L"simulation/ai/" + m_AIName + L"/data.json";
-			JS::RootedValue metadata(cx, m_Worker.LoadMetadata(path).get());
+			JS::RootedValue metadata(cx);
+			m_Worker.LoadMetadata(path, &metadata);
 			if (metadata.isUndefined())
 			{
 				LOGERROR(L"Failed to create AI player: can't find %ls", path.string().c_str());
@@ -741,15 +742,15 @@ public:
 	}
 
 private:
-	CScriptValRooted LoadMetadata(const VfsPath& path)
+	void LoadMetadata(const VfsPath& path, JS::MutableHandleValue out)
 	{
 		if (m_PlayerMetadata.find(path) == m_PlayerMetadata.end())
 		{
 			// Load and cache the AI player metadata
-			m_PlayerMetadata[path] = m_ScriptInterface->ReadJSONFile(path);
+			m_ScriptInterface->ReadJSONFile(path, out);
+			m_PlayerMetadata[path] = CScriptValRooted(m_ScriptInterface->GetContext(), out);
 		}
-
-		return m_PlayerMetadata[path];
+		out.set(m_PlayerMetadata[path].get());
 	}
 
 	void PerformComputation()

source/simulation2/components/CCmpCommandQueue.cpp

@@ -89,12 +89,16 @@ public:
 		m_LocalQueue.push_back(c);
 	}
 
-	virtual void PostNetworkCommand(CScriptVal cmd)
+	virtual void PostNetworkCommand(CScriptVal cmd1)
 	{
 		JSContext* cx = GetSimContext().GetScriptInterface().GetContext();
+		JSAutoRequest rq(cx);
+		
+		// TODO: With ESR31 we should be able to take JS::HandleValue directly
+		JS::RootedValue cmd(cx, cmd1.get());
 
 		PROFILE2_EVENT("post net command");
-		PROFILE2_ATTR("command: %s", GetSimContext().GetScriptInterface().StringifyJSON(cmd.get(), false).c_str());
+		PROFILE2_ATTR("command: %s", GetSimContext().GetScriptInterface().StringifyJSON(&cmd, false).c_str());
 
 		// TODO: would be nicer to not use globals
 		if (g_Game && g_Game->GetTurnManager())

source/simulation2/components/ICmpAIManager.cpp

@@ -60,9 +60,11 @@ public:
 		std::wstring dirname = GetWstringFromWpath(*it);
 
 		JS::RootedValue ai(cx);
+		JS::RootedValue data(cx);
+		self->m_ScriptInterface.ReadJSONFile(pathname, &data);
 		self->m_ScriptInterface.Eval("({})", &ai);
 		self->m_ScriptInterface.SetProperty(ai, "id", dirname, true);
-		self->m_ScriptInterface.SetProperty(ai, "data", self->m_ScriptInterface.ReadJSONFile(pathname), true);
+		self->m_ScriptInterface.SetProperty(ai, "data", data, true);
 		self->m_AIs.push_back(CScriptValRooted(cx, ai));
 
 		return INFO::OK;

source/simulation2/system/ComponentManager.cpp

@@ -1147,13 +1147,16 @@ CScriptVal CComponentManager::Script_ReadCivJSONFile(ScriptInterface::CxPrivate*
 	return ReadJSONFile(pCxPrivate, L"civs", fileName);
 }
 
-CScriptVal CComponentManager::ReadJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring filePath, std::wstring fileName)
+JS::Value CComponentManager::ReadJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring filePath, std::wstring fileName)
 {
 	CComponentManager* componentManager = static_cast<CComponentManager*> (pCxPrivate->pCBData);
+	JSContext* cx = pCxPrivate->pScriptInterface->GetContext();
+	JSAutoRequest rq(cx);
 
 	VfsPath path = VfsPath(filePath) / fileName;
-
-	return componentManager->GetScriptInterface().ReadJSONFile(path).get();
+	JS::RootedValue out(cx);
+	componentManager->GetScriptInterface().ReadJSONFile(path, &out);
+	return out.get();
 }
 	
 Status CComponentManager::FindJSONFilesCallback(const VfsPath& pathname, const CFileInfo& UNUSED(fileInfo), const uintptr_t cbData)

source/simulation2/system/ComponentManager.h

@@ -286,7 +286,7 @@ private:
 	static CScriptVal Script_ReadJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring fileName);
 	static CScriptVal Script_ReadCivJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring fileName);
 	static std::vector<std::string> Script_FindJSONFiles(ScriptInterface::CxPrivate* pCxPrivate, std::wstring subPath, bool recursive);
-	static CScriptVal ReadJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring filePath, std::wstring fileName);
+	static JS::Value ReadJSONFile(ScriptInterface::CxPrivate* pCxPrivate, std::wstring filePath, std::wstring fileName);
 	
 	// callback function to handle recursively finding files in a directory
 	static Status FindJSONFilesCallback(const VfsPath&, const CFileInfo&, const uintptr_t);

source/tools/atlas/GameInterface/Handlers/MapHandlers.cpp

@@ -91,7 +91,8 @@ QUERYHANDLER(GenerateMap)
 	JSContext* cx = scriptInterface.GetContext();
 	JSAutoRequest rq(cx);
 	
-	JS::RootedValue settings(cx, scriptInterface.ParseJSON(*msg->settings).get());
+	JS::RootedValue settings(cx);
+	scriptInterface.ParseJSON(*msg->settings, &settings);
 
 	JS::RootedValue attrs(cx);
 	scriptInterface.Eval("({})", &attrs);