🚀 go-pugleaf

John Shalf wrote:
> Varargs allows you to unpack a variable number of arguments from a
> subroutine call at runtime.  You would think there would be a way to
> *pack* a variable number of arguments for a subroutine call at runtime.
> However the C faq says;
>[snip]
> no! :)
>[/snip]
> 
> Has anyone come up with a saner, more portable method for generating
> subroutines calls with a variable number of arguments at runtime?
> 

Im curious, is there no way for you to design your application so that
you could load your parameters into a structure or array?  As a possible
scenario howabout something like this (on the fly) example:

struct arg_list
{
   int ptype;
   void *pval;
};

struct arg_list **plist;

   /*---------------------------------------------------------------*/
   /* Now for PNUM args we need space to point to PNUM of the above */
   /*---------------------------------------------------------------*/
   plist = (arg_list **)malloc(sizeof(*plist)*PNUM); /* List */

   /*----------------------------------------------------------------*/
   /* And now malloc the structure itself for each param.  Excuse me */
   /* for dumb mistakes here... alright?                             */
   /*----------------------------------------------------------------*/
   for (i=0;i<PNUM;i++)
   {
      plist[i]=(arg_list *)malloc(sizeof(**plist)); /* Structure */

      /*------------------------------------------*/
      /* And now, the space for each param itself */
      /*------------------------------------------*/
      plist[i]->pval=(void *)malloc(PARAM_SIZE);

      /*----------------------------*/
      /* Put value in the structure */
      /*----------------------------*/
      plist[i]->ptype = ENUMERATED_TYPE;
      memcpy(plist[i]->pval,PARAM_ADDRESS);
   }

   /*-----------------------------*/
   /* Finally, call some function */
   /*-----------------------------*/
   varparmfunc(PNUM,plist);

The concept should work, if not this exact code... and if you do implement
something like this make sure you check that your malloc works!

Andrew Smith
Custom Innovative Solutions
http://www.cisc.com/