Re: static function tables

[Todd Hoff <tmh at possibility dot com>]

Ken wrote:

> The catch in this case is that the objects are static, and this is a
> memory-limited embedded system where I don't want to copy a const array
> of structures in ROM into equivalent C++ structures in RAM. This is kind
> of a general problem in using C++ in a memory-limited environment. 

I would be inclined to overload the new operator and take the memory
out of a static array or some other fixed source. Best of both worlds.
In fact, in a memory constrained system i would overload the global
new and allocate memory from pools of fixed sized buffers. Works
best i think.

>There
> are cases where it would be nice to initialize static const C++ objects
> at compile or link time (on the host) rather than just before main() (on
> the target).

Some say potatoes...

> I've seen a trick lately (I think in Embedded Systems Programming) where
> one exposes a C++ class that defines an internal private struct for the
> static const data. Something like
> 
>  class public_class
>  {
>  private:
>      struct static_data { ... };
>      static const static_data data[]; // stored in ROM
>  };
> 
> This looks applicable to the situation.

This is the pimple pattern or the handle pattern. Works fine.
Just better make sure your rom address is correct!

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   Desperate measures require the invention of desperate times. 
      -- Todd Hoff