Weekly Status Report #3: Loader quality of life

Hi,

This week I made various platform-dependent changes to extend support 
for special keys/modifier combos under UEFI, BIOS, and u-boot.
For UEFI it was just a matter of translating the UEFI scancodes/modifier 
mask into an ANSI escape.
For BIOS, I had to jump through some hoops since scancodes change based 
on modifiers (and didn't follow any patterns), but it was nothing a 
lookup table couldn't fix.
u-boot was a bit of a different story though, since it already provides 
input via ANSI escapes, but doesn't implement all special keys or all 
key/modifiers combos. Beyond needing upstream changes, I also ran into 
the problem of my changes not having any effect.
Both physical and virtualized hardware didn't seem to reach my code 
(despite it being present in the binary). I assume this is simply for a 
u-boot/non-x86 specific reason I don't fully understand yet. Since I 
didn't specifically plan for u-boot support in my proposal, I'm just 
going to let this problem stew while I get more familiar with the 
non-x86 booting world and try again later on.

Connor