Re: Best way to save/re-load an lua state

["kathrin_69@..." <kathrin_69@...>]

David Given wrote:
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> kathrin_69@gmx.de wrote:
> [...]
>   
> > If I would overwrite it in a way so that all memory used by  my
> > lua_State* is inside my own (pre-allocated) buffer, I could just save
> > and re-load that buffer to/from disc and resume execution. What do you
> > think, will this work? It sounds pretty easy so far.
> >     
>
> This will only work if you new buffer is loaded at the same address as
> the old one, as there'll be pointers embedded all throughout the data.
>   
Yes. But how can this be achieved? Is there any windows API to get a 
fixed address? Or do I have to use a DLL with an "shared" part and load 
that DLL on a fixed address into process space?

> And if there happen to be pointers anywhere else --- such as on the
> stack --- then you will be in for what is technically known as A World
> Of Pain! 
I'm not the most experienced C-programmer, but if I save the lua_State* 
between two calls to lua_Resume(), there shouldn't be any process stack 
memory in use by Lua functions, because all Lua-functions are already 
returned and therefore all stack is un-winded. Am I wrong with this?

> Personally I'd go for something like Pluto, which
> saves/restores the state at a much higher level.
>   
I have not tried it yet, but I fear serialization will be to slow for my 
needs, because I'll have to save the lua_State on every cycle of a 
simulation loop to allow precise/granular rollback.