Re: Addressing MVS control blocks from Hercules e.g. PSAAOLD/PSATOLD

>
> On Tue, 2008-08-19 at 17:16 +0000, michealbutz2002 wrote:
> > I am a an Assembler internals Guy and am trying to expand my
> > horizons  
> >
> > I am trying to display MVS info e.g. some of the things in HSCCMD.C
> >
> > In a GUI front I did a Windows API CreateProcess to Create a Window
> > 32 WinMain app to display info displayed in DOS box from hsccmd.c
> >
> >
> > you have given me some idea of what I need to do
> >
> > let me see if this can help
>
> What Roger said.  Stuff in mainstor is big-endian.  Stuff in control
> blocks is usually host-endian (little-endian on intel).  You should
> always know how many bytes you are fetching from mainstor (whereas on
> host you don't know if `void *ptr' is 4, 8 or some other number of
> bytes).
>
> To do virtual addressing, you should use the MADDR macro.  The control
> regs (2 (primary) or 7 (secondary) or 13 (home) or etc) must be set up.
> The virtual address should probably be resolvable to a real address else
> you are going to take a page interrupt.
>
> Below is some code I wrote a while back that fits into an instruction.
>
> Bonus points to anyone that can explain what it does ;-)
>
> Extra bonus points if you can explain why this code shows you cannot
> necessarily trust your hardware vendor.
>
> Greg
>
> --- hercules-cvs/general2.c 2007-01-13 02:21:48.000000000 -0500
> +++ hercules/general2.c 2007-02-04 13:03:06.000000000 -0500
> @@ -1373,6 +1373,24 @@
>      }
>  #endif
>  
> +    if (i == 131 && sysblk.stepaddr[0] == 131)
> +    {
> +        BYTE *mn = NULL;
> +        ARCH_DEP(display_inst)(regs, inst);
> +        if (regs->GR_L(1))
> +            mn = MADDR(regs->GR_L(1),0,regs,ACCTYPE_READ,0);
> +        else if (regs->GR_L(0))
> +        {
> +            VADR p;
> +            p =