SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
This improves the speed of verifying Wii WIA/RVZ files.
For me, the verification speed for LZMA2-compressed files
has gone from 11-12 MiB/s to 13-14 MiB/s.
One thing VolumeVerifier does to achieve parallelism is to
compute hashes for one chunk of data while reading the next
chunk of data. In master, when reading data from a Wii
partition, each such chunk is 32 KiB. This is normally fine,
but with WIA and RVZ it leads to rather lopsided read times
(without the compute times being lopsided): The first 32 KiB
of each 2 MiB takes a long time to read, and the remaining
part of the 2 MiB can be read nearly instantly. (The WIA/RVZ
code has to read the entire 2 MiB in order to compute hashes
which appear at the beginning of the 2 MiB, and then caches
the result afterwards.) This leads to us at times not doing
much reading and at other times not doing much computation.
To improve this, this change makes us use 2 MiB chunks
instead of 32 KiB chunks when reading from Wii partitions.
(block = 32 KiB, group = 2 MiB)
This can't actually happen in practice due to how WAD files work,
but it's very easy to add support for thanks to the last commit,
so we might as well add support for it.
The performance gains of doing this aren't too important since you
normally wouldn't run into any disc image that has overlapping blocks
(which by extension means overlapping partitions), but this change also
lets us get rid of things like VolumeVerifier's mutex that used to
exist just for the sake of handling overlapping blocks.
Some of the device names can be ambiguous and require fully or partly
qualifying the name (e.g. IOS::HLE::FS::) in a somewhat verbose way.
Additionally, insufficiently qualified names are prone to breaking.
Consider the example of IOS::HLE::FS:: (namespace) and
IOS::HLE::Device::FS (class). If we use FS::Foo in a file that doesn't
know about the class, everything will work fine. However, as soon as
Device::FS is declared via a header include or even just forward
declared, that code will cease to compile because FS:: now resolves
to Device::FS if FS::Foo was used in the Device namespace.
It also leads to having to write IOS::ES:: to access ES types and
utilities even for code that is already under the IOS namespace.
The fix for this is simple: rename the device classes and give them
a "device" suffix in their names if the existing ones may be ambiguous.
This makes it clear whether we're referring to the device class or to
something else.
This is not any longer to type, considering it lets us get rid of the
Device namespace, which is now wholly unnecessary.
There are no functional changes in this commit.
A future commit will fix unnecessarily qualified names.
We want to use positional arguments in translatable strings
that have more than one argument so that translators can change
the order of them, but the question is: Should we also use
positional arguments in translatable strings with only one
argument? I think it makes most sense that way, partially
so that translators don't even have to be aware of the
non-positional syntax and partially because "translatable
strings use positional arguments" is an easier rule for us
to remember than "transitional strings which have more than
one argument use positional arguments". But let me know if
you have a different opinion.
Once nice benefit of fmt is that we can use positional arguments
in localizable strings. This a feature which has been
requested for the Korean translation of strings like
"Errors were found in %zu blocks in the %s partition."
and which will no doubt be useful for other languages too.
The new hash check catches essentially all desync problems
that VolumeVerifier can catch, so from the user's perspective,
such problems will result in Dolphin refusing to start the
game on netplay rather than actually getting a desync.
When I first made VolumeVerifier, I figured that the distinction
between an unsigned ticket and an unsigned TMD was a technical
detail that users would have no reason to care about. However,
while this might be true for discs, it isn't equally true for
WADs, due to the widespread practice of fakesigning tickets to
set the console ID to 0. This practice does not require
fakesigning the TMD (though apparently people do it anyway,
at least sometimes...), and the presence of a correctly signed
TMD is a useful indicator that the contents have not been
tampered with, even if the ticket isn't correctly signed.
It is my opinion that nobody should use NKit disc images without
being aware of the drawbacks of them. Since it seems like almost
nobody who is using NKit disc images knows what NKit is (hmm, now
how could that have happened...?), I am adding a warning to Dolphin
so that you can't run NKit disc images without finding out about the
drawbacks. In case someone really does want to use NKit disc images,
the warning has a "Don't show this again" option. Unfortunately, I
can't retroactively add the warning where it's most needed:
in Dolphin 5.0, which does not support Wii NKit disc images.
The constant DESIRED_BUFFER_SIZE was determined by multiplying the
old hardcoded value 32 with the default GCZ block size 16 KiB.
Not sure if it actually is the best value, but it seems fine.
A small, nonexhaustive set of warning fixes. The DiscIO Volume change
is a workaround for a GCC bug [1] that causes returning an unengaged
std::optional to emit annoying -Wmaybe-uninitialized warnings.
This last change alone fixes pages upon pages of warnings since
Volume.h is included from several files.
-Wstringop-truncation is another irrelevant warning for us, but
unfortunately there seems to be no way to disable it without
adding ugly pragmas wherever the warning appears.
string_view is a thin wrapper around C strings, so it's more efficient
for constant strings than C++ strings.
The unordered_set<> also adds extra runtime overhead. For small arrays,
a simple linear search works. For larger arrays, std::binary_search()
works better than linear but without the unordered_set<> overhead.
ShouldBeDualLayer(): Removed a duplicate "SK8X52" entry.
This happens if someone manually downloads a regular datfile from
redump.org and puts it where Dolphin stores datfiles. Dolphin needs
"special" datfiles that contain fields for serials and versions.
Before this change, all discs (except Datel discs) would show up as
"Unknown disc" when using a regular datfile.
Pierre Bourdon