* Move out boot parameters to a separate struct, which is not part
of SConfig/ConfigManager because there is no reason for it to
be there.
* Move out file name parsing and constructing the appropriate params
from paths to a separate function that does that, and only that.
* For every different boot type we support, add a proper struct with
only the required parameters, with descriptive names and use
std::variant to only store what we need.
* Clean up the bHLE_BS2 stuff which made no sense sometimes. Now
instead of using bHLE_BS2 for two different things, both for storing
the user config setting and as a runtime boot parameter,
we simply replace the Disc boot params with BootParameters::IPL.
* Const correctness so it's clear what can or cannot update the config.
* Drop unused parameters and unneeded checks.
* Make a few checks a lot more concise. (Looking at you, extension
checks for disc images.)
* Remove a mildly terrible workaround where we needed to pass an empty
string in order to boot the GC IPL without any game inserted.
(Not required anymore thanks to std::variant and std::optional.)
The motivation for this are multiple: cleaning up and being able to add
support for booting an installed NAND title. Without this change, it'd
be pretty much impossible to implement that.
Also, using std::visit with std::variant makes the compiler do
additional type checks: now we're guaranteed that the boot code will
handle all boot types and no invalid boot type will be possible.
Normal users don't care about it. In fact, people care so
little about it that the Wii implementation of it was broken
starting from when it was implemented (eb65601) to 7 years
later (e0a47c1), apparently without anyone reporting it.
This makes the interface slightly cleaner and a bit more consistent
with the other getters. Still not fully the same, since the others
don't really handle failures with std::optional; but at least the
value is returned by value now, as opposed to having the function
take a pointer to a u64.
This gets rid of some assumptions that non-DiscIO code was making about
volume types. It's better to encapsulate as many of the volume type
differences as possible in DiscIO.
Made possible by PR #2353.
This makes it hard to support different boot params for different boot
types. We should not be making the assumption that Dolphin will
always be booting directly from a file (and in particular, only
using a string).
It's incompatible with future changes that will allow Dolphin to boot
a NAND title properly from well, the NAND, as opposed to booting from
WADs. (And no, treating the title TMD as a "bootable" path doesn't
count. Especially when that approach won't work with NAND images
or IOS LLE.)
And it's confusing to expose this functionality from the UI. It's
pretty bad for UX to change the play button's behaviour depending on
whether the user has launched something before, configured a default
file to boot, added a directory to their game paths.
