Re: [hatari-devel] pVideoRaster in memory snapshot?

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 08/04/2020 à 22:22, Eero Tamminen a écrit :
> Hi Nicolas,
>
> Why this ignores the stored "pVideoRaster" value and restores it instead 
> to "VideoBase" variable STRam offset?
> -------------------------
> void Video_MemorySnapShot_Capture(bool bSave)
> {
>          Uint32  addr;
> ...
>          MemorySnapShot_Store(&VideoBase, sizeof(VideoBase));
>          if ( bSave )
>          {
>                  addr = pVideoRaster - STRam;
>                  MemorySnapShot_Store(&addr, sizeof(addr));
>          }
>          else
>          {
>                  MemorySnapShot_Store(&addr, sizeof(addr));
>                  pVideoRaster = &STRam[VideoBase];
>          }
> -------------------------
>
> (If it's intentional, there should be a comment about the reason.)

Hi

that's because pVideoRaster is a pointer inside the host PC's RAM. So 
there's no point in saving pointer to RAM, it would be wrong, you can't 
restore them.

There're a fews others places in other HW components (fdc.c IIRC) where 
we need to save offsets relative to an allocated buffer, then on restore 
allocate a new buffer and add offset to get the correct value again.

I'm not sure this requires a comment (or maybe there's a comment in 
fdc.c but not here).

Nicolas