lockable Lua object; "Lua" alias to replace "lua_State"

stepmania/src/LuaManager.cpp

@@ -5,6 +5,7 @@
 #include "RageUtil.h"
 #include "RageLog.h"
 #include "RageFile.h"
+#include "RageThreads.h"
 #include "arch/Dialog/Dialog.h"
 #include "Foreach.h"
 
@@ -152,6 +153,7 @@ LuaManager::LuaManager()
 	LUA = this;	// so that LUA is available when we call the Register functions
 
 	L = NULL;
+	m_pLock = new RageMutex( "Lua" );
 
 	ResetState();
 }
@@ -159,8 +161,23 @@ LuaManager::LuaManager()
 LuaManager::~LuaManager()
 {
 	lua_close( L );
+	delete m_pLock;
 }
 
+Lua *LuaManager::Get()
+{
+	m_pLock->Lock();
+	return L;
+}
+
+void LuaManager::Release( Lua *&p )
+{
+	ASSERT( p == L );
+	m_pLock->Unlock();
+	p = NULL;
+}
+
+
 void LuaManager::RegisterTypes()
 {
 	for( const LuaFunctionList *p = g_LuaFunctions; p; p=p->next )

stepmania/src/LuaManager.h

@@ -2,7 +2,9 @@
 #define LUA_MANAGER_H
 
 struct lua_State;
+typedef lua_State Lua;
 typedef void (*RegisterWithLuaFn)(lua_State*);
+class RageMutex;
 
 extern "C"
 {
@@ -49,6 +51,9 @@ public:
 	LuaManager();
 	~LuaManager();
 
+	Lua *Get();
+	void Release( Lua *&p );
+
 	void PrepareExpression( CString &sInOut );	// strip "//" comments and "+"
 
 	bool RunScriptFile( const CString &sFile );
@@ -96,6 +101,8 @@ public:
 	lua_State *L;
 
 private:
+	RageMutex *m_pLock;
+
 	/* Register all subscribing types.  There's no harm in registering when already registered. */
 	void RegisterTypes();
 };