Don't use pread, instead map the file and madvise larger blocks. This
removes copying overhead as its just mapping file pages in instead.
Also splits the implementation of file reading from hashing to make
tinkering less involved, as if I want more performance out of this (say
due to live hashing) then it's easier to tinker.
Improves hashing performance from ~2.2GB/s to ~3.6GB/s on my system,
which is CPU bounded by xxhash here.
Since `HadError` is a lambda that handles FD closing this was a double
FD close. Just move the xxhash state freeing in there as well and remove
the FD and hash freeing. Fixes the double free.
The final tail of the file reading was incorrect, so our hashing was
"correct" but it was using stale data from the previous block size read.
Noticed this while wiring up the CI rootfs fetching since the hashing is
a lot simpler there.
Now instead of reading a tail, just attempt to read the full block size
and use the resulting data size instead. Confirmed it matches expected
results now.
In the process we are going to need to update hyperlinks and hashes
anyway, change the hash to XXH3 so it is faster to run.
This tool supports both a zenity and tty interface.
TTY will be presented if available while Zenity will be used otherwise.
This tool pulls a rootfs list from https://rootfs.fex-emu.org/
It then allows you to select a rootfs from the list, download it, place
it in to the correct working folder, extract it if desired, and set it
as the current default RootFS.
This requires curl and potentially zenity installed to use.
Maybe also unsquashfs if the user chooses to extract the image.
This is an all in one tool to quickly get a new user up and running.
Additionally if you pass in a file path in to the tool, it will generate
an xxhash of the file and exit out. This is the hash used to ensure the
files are valid.
Ryan Houdek