So far in all our uses of ScopeGuard, the type of the callable is
usually just a lambda or a function pointer, so there is no need
to rely on std::function's type erasure.
While the cost of using std::function is probably negligible, it still
causes some unnecessary overhead that can be avoided by making
ScopeGuard a templated class. Thanks to class template argument
deduction in C++17 most existing usages do not even need to be changed.
See https://godbolt.org/z/KcoPni for a comparison between
a ScopeGuard that uses std::function and one that doesn't
Some locales (e.g. fr_FR.UTF-8 on ArchLinux) don't split the string stream on a space. As such, when extracted formatted data from te stream, it will return the two numbers as one for the first call, effectively overflowing the u32 variable, then will do an out-of-bounds read for the second call. Forcing the use of the C locale on the streams where it would cause a problem allows to workaround this behavior.
This fixes CreateFullPath to not create directories when it is known
that they already exist, instead of calling CreateDirectory anyway
and checking if the error is AlreadyExists. (That doesn't work
now that we have an accurate implementation of CreateDirectory
that performs permission checks before checking for existence.)
I'm not sure what I was thinking when I wrote that function.
Also adds some tests for CreateFullPath.
Fixes a regression from #8539.
CreateDirectory was the correct function to use for creating
directories since parent directories already exist and are
not owned by the system menu.
Now that all FS functions that create new inodes are properly
implemented, we can make GetMetadata actually return correct file
metadata rather than giving fixed information. The hack for the DQX
installer can also be removed now since our ES and FS keep track of
caller UID/GIDs now.
With the CreateFile/CreateDirectory fix and this commit, we can
finally return correct results in ReadDirectory and the sorting
hack -- whose purpose was to prevent certain versions of the
System Menu from crashing -- can be removed too.
CreateDirectory does not create missing parent directories. If that
behaviour is desired, CreateFullPath should be used instead.
(These small misuses went unnoticed since the previous implementation
of CreateDirectory automatically created parent directories.)
Previously, the FS root directory would get created as a side
effect of calling CreateDirectory during boot (since the
implementation was sloppy and used File::CreateFullDir).
Since CreateDirectory no longer does that, it is necessary to ensure
that the FS root directory does exist by creating it explicitly.
Some official titles rely on implementation details of Nintendo's
FS sysmodule and will not work properly if those are changed.
Notably, some games and older versions of the System Menu appear
to be relying on the order of files returned by FS::ReadDirectory
and will either fail to find their save data (for Bolt) or
outright crash (for the System Menu).
Some titles also actually expect filesystem metadata to be correct.
One title that has been confirmed to do this is DQX, which generates
paths based on the GID of files within its own title directory.
While it is easy to make workarounds for these issues -- and in fact
we already do have some for the sysmenu and DQX, having hacks
is obviously nonideal and adding yet another hack would be required
to fix Bolt -- one that would be even uglier.
Furthermore, while it is currently unknown whether any official
title cares about permissions, the lack of FS metadata means that
we are unable to implement them if that turns out to be desirable
or necessary.
By adding a FST, we can implement things correctly and solve all
those problems without hacks.
Apart from DQX, the sysmenu and Bolt, this changeset also fixes
the Photo Channel complaining about corrupted system files
on the initial launch.
This first commit adds the basic structures and functions that
are necessary to load, save, query and update our version of the FST.
For simplicity, a binary format that is inspired from Nintendo's FST
structure was chosen for serialization. It is not expected to ever
receive an update.
PS: an update on the NAND image backend:
A long time ago I had planned to add another FS backend which would
be using a NAND image/blob as the storage. While I have already
written an implementation that has been tested, solves all the
aforementioned issues and more, produces images that are fully
compatible with IOS's FS driver, I feel like NAND images raise too
many issues: savestate sizes, code complexity and maintenance cost.
Since many fixes and additions that are part of that implementation
(e.g. FS timings, utility structures, FST) have already been merged
or will be submitted as part of this changeset, I will likely not
submit the branch.
JosJuice