It seems like we spend a lot of the game list scanning time in
updateAdditionalMetadata, which I suppose makes sense considering
how many different files that function attempts to open.
With the addition of just one little atomic operation, we can make
it safe to call updateAdditionalMetadata without holding a lock.
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.
Back when I wrote this code, I believe I set it to use a custom path
so that the cache would end up in a directory which Android considers
to be a cache directory. But nowadays the directory which Dolphin's
C++ code considers to be the cache directory is such a directory,
so there's no longer any reason to override the default path.
This feature was originally exclusive to the previous iteration of
DolphinQt (the one that was the reason for the current iteration
being named DolphinQt2 initially).
https://bugs.dolphin-emu.org/issues/8949
The difference between Dolphin's game IDs and GameTDB's game IDs
is that GameTDB uses four characters for non-disc titles, whereas
Dolphin uses six characters for all titles.
This fixes:
- TitleDatabase considering Datel discs to be NHL Hitz 2002
- Gecko code downloading not working for discs with IDs starting with P
- Cover downloading mixing up discs with channels (e.g. Mario Kart Wii
and Mario Kart Channel) and making extra HTTP requests. (Android was
actually doing a better job at this than DolphinQt!)
The header of a Wii disc can be read from two places: The
unencrypted area at the beginning of the disc, or the beginning of
the game partition. The two copies are usually identical (except
for 0x60 and 0x61), but there are exceptions. For most of Dolphin's
history, we have been reading from the header inside the game
partition when getting metadata. This was however not the case
starting with 4.0-4901 and ending with 5.0-3762. This commit once
again makes Dolphin read metadata from the unencrypted header,
because of the following reasons that I recently was informed about:
- The "pink fish" disc has the game ID 410E01 in the unencrypted
header but the placeholder game ID RELSAB in the partition header.
- The revisions of some games differ between the two headers,
with the unencrypted one making more sense.
(See https://bugs.dolphin-emu.org/issues/11387)
For better or worse, this also means that sloppily hacked games where
only the game ID in the unencrypted header has been changed now will
use that modified game ID. And unlike with the partition header,
there is no signing or hashing that can tell us whether the
unencrypted header has been modified by someone other than Nintendo.
Deduplicates code, and gets rid of some problems the old code had
(such as: bad performance when calling native functions, only one
disc showing up for multi-disc games, Wii banners being low-res,
unnecessarily much effort being needed for adding more metadata).
Regression from 1f1dae3.
This problem doesn't happen in DolphinWX as far as I know, but if
you've ran into the problem in DolphinQt2, it will carry over to
DolphinWX because of the shared game list cache.
The original reason I wanted to do this was so that we can replace
the Android-specific code with this in the future, but of course,
just deduplicating between DolphinWX and DolphinQt2 is nice too.
Fixes:
- DolphinQt2 showing the wrong size for split WBFS disc images.
- DolphinQt2 being case sensitive when checking if a file is a DOL/ELF.
- DolphinQt2 not detecting when a Wii banner has become available
after the game list cache was created.
Removes:
- DolphinWX's ability to load PNGs as custom banners. But it was
already rather broken (see https://bugs.dolphin-emu.org/issues/10365
and https://bugs.dolphin-emu.org/issues/10366). The reason I removed
this was because PNG decoding relied on wx code and we don't have any
good non-wx/Qt code for loading PNG files right now (let's not use
SOIL), but we should be able to use libpng directly to implement PNG
loading in the future.
- DolphinQt2's ability to ignore a cached game if the last modified
time differs. We currently don't have a non-wx/Qt way to get the time.
