c5fa470 made the extension check discard directories, but
only in the new code that currently only is used on Windows.
Let's add an equivalent check in the old code so that the
behavior is consistent across platforms.
This seems like an oversight in the old code, because
what's the point of loading user files if the titles
in them are going to be ignored for nearly all games?
This commit fixes the issue by making the first LoadMap
variant not overwrite entries and making the constructor
do everything in the opposite order. An alternative solution
would be to make the second LoadMap variant overwrite entries.
This fixes the global-static fifo object causing infinite hangs in some
cases. Notably, failure to initialize a graphics backend would result in
BlockingLoop::Prepare being called but never executing Run(), leaving the
object in a bad state.
The sanity check runs *before* finalising the import, so at that time
the whole title directory is still in /import and not in /title.
This means we should check for contents there, not in /title. Whoops.
The efficient function (that is nearly the same as
https://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2)
replaces one loop based instance (which also reused the xx variable
afterwards, whereas it should have used htabmask instead) and one
instance using the population count a.k.a. Hamming weigth.
This one verifies bitmasks where low bits are set to 1 (hence the name).
Any stray 0 among the lower ones or any stray 1 among the higher zeros
renders the mask invalid.
The edge cases of all zeros and all ones are considered valid masks.
It uses an efficient implementation. It's the counterpart of
https://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2
Simpler, and puts the call to CheckIntegrity right where it should be,
instead of being hidden somewhere in a thread class.
This also makes it more obvious what we're getting from the async task.
Oh, and coincidentally, this fixes a random crash that could occur
during the check. I'm not sure why.
Michael Maltese