[fpc-devel] Re: FPC related fairy tale

[Michael Schnell]

On 10/19/2012 03:29 PM, Sven Barth wrote:
> It would be easier if you'd use the C code from within FPC code. 
I don't think I can easily do this, as there is a booting system called 
"Leash" provided by Innovasic, that finally runs the user code 
(everything is compiled to a single loadable/executable file, though, 
it's embedded stuff in the end...) Leash is highly configurable, 
initializes the chip internal hardware and finally starts and monitors 
four user's hardware-Threads, that work (and in the Eclipse-based 
debugger look as if there really were)  four (plus one) independent 
processors.

So, if you think it's not easily doable to link a set of fpc procedures 
into this monolithic executable, maybe writing a little loader (e.g. 
loading the fpc executable into a dedicated predefined memory location) 
would be easier to do and workable at least for testing.


> You might also circumvent heap manager issues by using the "cmem" unit. 
Or in the loader providing a cmem workalike, that preforms a callback to 
the C-generated infrastructure, that of course does provide malloc() and 
friends...

> But as I already wrote I'm currently using the user space emulation of 
> QEMU and with that I don't have the need to find/compile corresponding 
> C libraries and I'd anyway like to have FPCs normal syscall interface 
> for Linux working. Also I don't know how well FPC will handle it if I 
> let it link to libraries as this is not tested yet...

As my system obviously does not run Linux, I hope I might be able to 
provide some kind of infrastructure that allows to decently execute FPC 
generated files. (This maybe in fact is similar to what QEMU does - 
without the code-interpreter.)

Thanks,
-Michael