In the continuous effort of better handling OOM in the kernel,
we want to move away from all AK::String usage. One of the final
pieces left to accomplish this goal is replacing all of the usages
of `String::formatted` with something that can actually propagate
failure.
The StringBuilder API was enhanced in the recent past to propagate
failure and thus a slightly modified version of what exists in
`AK::format` will work well for implementing failable format with
`KString`.
Previously, Virtio console ports would not show up in `/sys/dev/char/`.
Also adds support to `SystemServer` to create more than one console
port device in `/dev/` in the multiport case.
The fixes are:
1. Don't copy PCI::DeviceIdentifier during construction. This is a heavy
structure to copy so we definitely don't want to do that. Instead, use
a const reference to it like what happens in other parts in the Kernel.
2. Declare the constructor as explicit to avoid construction errors.
Previously we `VERIFY()`ed that the device supports variable-rate audio
(VRA). Now, we query the VRA bit and if VRA is not supported, we do not
enable double-rate audio and disallow setting any sample rate except
the fixed 48kHz rate as defined by the AC'97 specification. This should
allow the driver to function on a wider array of hardware.
Note that in the AC'97 specification, DRA without VRA is allowed when
supported: this effectively doubles the sample rate to 96kHZ. For now,
we ignore that possibility and let it default to 48kHZ.
Before, only KeyEvent::code_point took the user's keyboard layout
into consideration, while KeyEvent::key was hardcoded QWERTY. This
affected, among other things, Vim Emulation.
Now, KeyEvent::key respects the user's keyboard layout, so will be the
same as KeyEvent::code_point for visible (alphanumeric + symbol) keys.
Co-Authored-By: Ben Wiederhake <BenWiederhake.GitHub@gmx.de>
We were returning `int`s from two functions that caused `ErrorOr` to
not recognize the error codes as a special case. For example,
`ETIMEDOUT` was returned as the positive number 66 resulting in all
kinds of defective behavior.
As a result, SDL2's timer subsystem was not working at all, since the
`SDL_MUTEX_TIMEDOUT` value was never returned.
Executing `asctl set r 96000` no longer results in weird sample rates
being set on the audio devices. SB16 checks for a sample rate between 1
and 44100 Hz, while AC97 implements double-rate support which allows
sample rates between 8kHz and 96kHZ.
This factors out some hardcoded PCMOut registers into a new private
class called AC97Channel, which wraps around a channel's registers and
provides some shared functionality.
No functional changes.
To make sure we don't lose changes, shared file mappings will now be
fully synced when they are unmapped, whether explicitly or implicitly
(by the program exiting/crashing/etc.)
This can incur a lot of work, since we don't keep track of dirty pages,
but that's something we can optimize down the road. :^)
This allows userspace to trigger a full (FIXME) flush of a shared file
mapping to disk. We iterate over all the mapped pages in the VMObject
and write them out to the underlying inode, one by one. This is rather
naive, and there's lots of room for improvement.
Note that shared file mappings are currently not possible since mmap()
returns ENOTSUP for PROT_WRITE+MAP_SHARED. That restriction will be
removed in a subsequent commit. :^)
