wengxt
Due to the new major fcitx version is coming close, the existing code need to be ported to use new Fcitx dbus interface.
The new dbus interface is supported by both fcitx 4 and 5, and has a good side effect, which is that it will work with flatpak for free. Also the patch remove the dependency on fcitx header. Instead, it just hardcodes a few enum value in the code so need to handle the different header for fcitx4 or 5.
There are multiple SDL APIs that internally sink into dbus calls, e.g. battery
status, thread priority. If those calls happen in different threads simultaneously
it can result in dbus crashes.
To abide by dbus's multithreading guidelines we must call dbus_threads_init_default()
to enable dbus's internal locking mechanisms:
https://dbus.freedesktop.org/doc/api/html/group__DBusThreads.html#gac7b8a7001befc3eaa8c6b043151008dc
Additionally, access to a DBusMessage must be synchronized between threads.
SDL was already abiding that guideline as the DBusMessage structs aren't shared.
The following email from the dbus mailing list hints that arbitrating access to
the DBusConnection on the SDL may also be required:
https://lists.freedesktop.org/archives/dbus/2017-September/017306.html
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
