Question

I’m using LuaInterface for scripting in a game I’m making.

The scripting works quite nice, but somehow I’m getting a lot of random exceptions.

I’ve narrowed the problem down to where I call lua functions from C# code, which are invoked from another thread, handling networking with the gameserver.

I think what is happening, is that the lua code is being run, and lua functions are called from C# from another thread, which causes the random errors.

How I’m calling the functions from C#:

function.Call(message);

function is of type LuaFunction and message is a custom object.

Errors I’m getting:

• A first chance exception of type ‘LuaInterface.LuaScriptException’
  occurred in LuaInterface.dll
• Error running lua: function
• A first chance exception of type ‘LuaInterface.LuaScriptException’
  occurred in LuaInterface.dll
• Unable to open script: mainmenu/console

Could it have to do with running lua functions from threads other than the thread the LuaVM was created on?

Answer 1

Lua is not thread safe. You either need to have a Lua state per thread and call the thread specific state, or place locks around any Lua calls.