uing vbe commands

[Gerardo Richarte]

Hi, I'm having problems with the vbe commands, specially if I compile 
grub (0.97) myself.

The first problem I had (and could finally solve) was that, in 
vbeprobe_func() the low order byte of the variable mode_number was 
overwriten (set to zero) by the call to get_vbe_mode_info(). I found 
this by adding a grub_printf() before and after this call, and seeing 
how the value changed (for example from -1 to 0xffffff00 or from 0x141 
to 0x100).
   My fix is to make vbe_mode.reserved3 bigger (I made it 190 bytes 
instead of the original 189) like in:

shared.h:

struct vbe_mode {
  ...
   unsigned char reserved3[190];
} __attribute__ ((packed));
  
   I read somewhere that this strcture must be 256 bytes, but, as far 
as I can count (tried twice) the original structure has 255 bytes, which 
would make sence.

   In short, my fix is to make reserved3 have 190 bytes.

   I also added a new command: setvbe, which will change the video mode 
and continue (cut&pasted from testvbe). My plan is to use this to 
bootstrap the development of some graphic mode bottable stuff.

   At some point I also thought of implementing the support for video 
mode selection of the multiboot loader of GRUB Legacy, I don't know if 
this makes sence or not, in the view of GRUB2. Any thoughts?

   hope this helps.
   thanks a lot

   gera