Date: Tue, 12 Sep 1995 23:19:04 -0400 (EDT)
From: Cuthalion / Sliced Bread <enrico AT max DOT tiac DOT net>
To: Mat Hostetter <mat AT ardi DOT com>
Cc: Paul <digisoft AT eis DOT net DOT au>, djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: interrupt stops being invoked

On Tue, 12 Sep 1995, Mat Hostetter wrote:

>     Paul> How can you get the size of a piece of "C" code that
>     Paul> services the interrupt so that it can be locked.  Up till
>     Paul> now I just lock it all to be safe.
> 
> As a TOTALLY EVIL hack, you can do something like:
> 
> ----------------------------------------------------------------------
> void interrupt_memory_start (void) { }
> 
> void my_interrupt_handler (void)
> {
>   ...
> }
> 
> void interrupt_memory_end (void) { }
> ----------------------------------------------------------------------
> 
> 
> and then lock:
> 
> 	(char *) interrupt_memory_end - (char *) interrupt_memory_start
> 
> bytes, starting at:
> 
> 	(char *) interrupt_memory_start
> 
> Of course, there's no guarantee that this will work (I think even
> casting a function pointer to a char * is forbidden) but it happens to
> be the case that this works with the latest djgpp (just make sure all
> of your functions are non-static).
> 
	You can _DO_ That?  (Successfully, I mean?)  Wow!  I would have 
expected the compiler to outsmart me somehow and put things in a 
different order or something.

/***************************************************************
*** Jesse Morris *** enrico AT max DOT tiac DOT net *** jmorris AT ace DOT com ***
***************** Cuthalion / Sliced Bread  *******************/