Updates protocol and API documentation to specify that the modifiers
event should be sent by the EIS implementation every time the modifier
or group state changes, including when the change is triggered by key
events on the emulated keyboard.
The previous approach of expecting the client to track modifier state
using xkb_state_update_key() for injected keys resulted in multiple
opportunities for the client and server to get out of sync (both due to
unavoidable race conditions and due the client not having access to the
complete state used by the server to calculate state changes), with no
way for the client to ensure it had a correct modifier map short of
unbinding and rebinding the seat.
The new approach allows the client to track state solely by applying
modifiers events with xkb_state_update_mask(), simplifying client
implementation. Because the event is sent for all changes, the client
can use ei_connection.sync / ei_ping() to ensure that it has received
the latest state incorporating all key requests sent prior to the sync
request (along with any externally-caused modifier state changes that
may have occured up to the time the sync message was received).
Part-of: <https://gitlab.freedesktop.org/libinput/libei/-/merge_requests/318>
This event is required to fix an issue with the current
ei_callback.done handling in libeis: previously we would imediately send
the ei_callback.done upon receiving ei_connection.sync from the client.
This results in incorrect behavior as we may have events in the queue
(and/or pending a frame) that the EIS implementation hasn't seen yet.
For example a client sending:
- ei_pointer.motion
- ei_connection.sync
- ei_device.frame
- ei_connection.sync
Will queue a motion + frame event on the EIS side during eis_dispatch()
but immediately receive done events for both sync requests.
This could be handled purely internally by keeping the sync event in the
queue but hidden to the caller - and automatically calling done when
it's that events turn, i.e. something like:
```
struct eis_event *eis_get_event(struct eis) {
struct eis_event *e = first_event(eis);
if (e == EIS_EVENT_SYNC) {
eis_callback_send_done(e);
eis_event_unref(e);
e = next_event(eis);
}
return e;
}
```
but that opens us up to a set of potential bugs detailed in
https://gitlab.freedesktop.org/libinput/libei/-/issues/71#note_2694603
So let's go the easy route by having a new event type that does nothing
other than eis_event_unref() in the EIS implementation. This way we can
queue the event and have everything behave in-order and as expected.
Closes#71
Part-of: <https://gitlab.freedesktop.org/libinput/libei/-/merge_requests/316>
In the protocol it's a new request/event that is sent instead of the
touch up event.
In the library this is implemented as ei_touch_cancel() which
transparently sends cancel() or up depending on the EIS implementation
support. This is mirrored for the EIS implementation.
Where touch cancel is received as an event it is presented
as EI_EVENT_TOUCH_UP with an ei_event_touch_is_cancel() flag to
check if it was a cancel. This is required for backwards compatbility,
we cannot replace the TOUCH_UP event with a TOUCH_CANCEL event without
breaking existing callers. To add a new event type we would need clients
announcing support for those event types but that's an effort that's
better postponed until we have a stronger need for it (see #68).
Closes#60
Part-of: <https://gitlab.freedesktop.org/libinput/libei/-/merge_requests/308>
The socket backend is useful for debugging and testing but not for real
user-cases where the fd negotiation should be handled by the caller
(e.g. passing it down through the portal). Let's demote the socket
backend in favour of the fd backend.
Related https://gitlab.freedesktop.org/libinput/libei/-/issues/63
Build a separate libei-eierpecken.so that is identical to libei.so but
allows adding an offset to ei_now() for the eierpecken tests. That
offset is added to the return value of ei_now(), removing the real-time
dependency of the tests.
In other words, we can call peck_ei_add_time_offset(peck, s2us(5)) to
add 5 seconds to the time and continue the test as if that time has
elapsed.
This allows a caller to match up a region with other data, e.g. in the
remote desktop case the same mapping_id can be assigned to the pipewire
stream that represents that output.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Same as the libei function, there's a use-case for this especially when
dealing with receiver contexts. libei filters those but we can't rely on
that in the server so using this is a workaround.
Commit da37da1308 "ei: change the API to match the protocol interfaces closer"
change the event type numbers for per-capability grouping but the
follow-up commit e6954b76d for eis didn't do the same. Right now the
event types are out sync.
This doesn't technically matter as this is a libeis implementation
detail (those types don't exist on the protocol) but it'd still be nice
to sync them before we ship 1.0.
This is an ABI break but not an API break.
For frame events on a device it's likely that we want to use eis_now()
which takes the context. So let's make this easy enough to access
without having to carry extra variables in the caller. And the same for
the seat as well.
Approximately every user of libei(s) will want something like this for
easier debugging, converting the numeric event type into something that
can be printed into the debug logs.
Let's provide this here so this doesn't need to be duplicated.
Same as the corresponding ei change a few commits ago, this one does all
the EIS renaming in the same manner.
As with the libei changes, an EIS implementation must now handle the
EIS_DEVICE_CAP_BUTTON and EI_DEVICE_CAP_SCROLL capabilities. In
virtually all cases, clients will likely expect that a device with the
pointer or absolute pointer capabilities will also have button and
scroll capabilities.
Now that the protocol interfaces are more fine-grained, let's match this
with the C API too.
This is just a rename of things so that in general
ei_pointer_*foo now becomes ei_foo*.
A few notable renames for better readability here:
- ei_device_scroll_delta (because scroll_scroll is awkward)
- ei_event_scroll_get_dx/dy and
ei_event_scroll_get_discrete_dx/dy to indicate the delta-ness
Beyond that, clients must ensure to check/bind to the new
EI_DEVICE_CAP_BUTTON and EI_DEVICE_CAP_SCROLL capabilities to be able
to send button or scroll events.
Note that this API now allows for an EIS implementation to send a device
that only has a button or a scroll cap. Or a pointer cap without
buttons, etc. It's up to the clients how to handle such devices
(probably: ignore them).
With the planned switch to a protocol supporting multiple interfaces
(a la wayland), a single version number is no longer useful. Remove this
API, we can add something more specific later if we need to.
This makes it easier to correlate a particular input transaction
(whether there are events or not) with out-of-band information like the
planned portal InputCapture::Activated signal's "activation-id".
The primary use-case for these properties in libei itself was to send
some fixed information (pid, cmdline and conection type). In the portal
case, these can be obtained out-of-band via the portal. In the
non-portal case these can be obtained from the socket itself (fetch pid,
look up /proc/pid/cmdline) which is just as reliable as trusting
whatever libei sends.
The only other use-case for the properties was the activation id in the
InputCapture::Activated portal signal. This can be achieved with a
serial in the START_EMULATING event.
libreis was intended for an intermediary to set some information that
the libei client cannot be entrusted with. In particular this was the
application name, the allowed capabilities, and some properties that -
once set - the client could no longer change (appid as probably the only
really useful one). The price for this was a rather complicated version
negotiation dance before the initial CONNECT request.
Now that we have a clear view of what's going to happen -
RemoteDesktop.ConnectToEIS and the InputCapture portal - there is no
longer any need for libreis. The extra information that libreis would've
sent is communicated out-of-band in both portals and are known to the
compositor at the time the connection is being established.
So we can simply drop this, it's no longer required and dropping it
makes the protocol significantly simpler anyway.
Let the client set the version number it wants on Connect. There is new
public API to query the client/server's version as set once the connect
finished (eis_client_get_version() and ei_get_version()) but there is
currently no public API for the client to select the version it actually
wants, other than whatever both support. IOW, it's not possible for the
client to say "I want version 8 but if that's not supported, use version
5".
For all but the simplest loggers, the current approach of "this is a
continuation of the previous message" doesn't work well. The caller
cannot know whether the *current* message is complete until it receives
the next message - but that message may never come.
Drop this approach, if we need to compile multiple messages into one,
we can handle this internally and then pass it all as one message to the
caller.
Currently only implemented for frame events, the vague plan for the
future is to merely queue the device events internally and "release"
them once a frame event was received, retrofitting the timestamp to the
C event struct (i.e. making ei_event_get_time() available on all device
events).
Meanwhile, the frame event it is.
Creates the socket and adds it; is intended to be used to create client
connections that are passed via a secure channel, e.g. via portals.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
With passive libei contexts receiving events sent by the EIS
implementation, the type of device changes significantly. While a
relative input device could still send data in logical pixels,
absolute devices may not have that luxury.
Best example here is an external tablet (think: Wacom Intuos): that
tablet has no built-in mapping to a screen and thus cannot capture input
events in logical pixels.
Address this by adding a device type, either virtual or physical.
In terms of functionality, the device's type decides:
- only virtual devices have regions
- only physical devices have a size
The event API remains as-is but the event data not represents either
logical pixels (virtual devices) or mm (physical device).
An EIS implementation connected to a passive libei context would likely
create:
- a virtual relative device (sending deltas in logical pixels)
- one or more physical absolute devices (sending deltas in mm)
Previously, a client could only bind to a capability immediately after
SEAT_ADDED and with a rather awkward API to confirm the capabilities.
Change this to allow for dynamic binding of capabilities, i.e. a client
calls ei_bind_capability() or ei_unbind_capability() whenever it feels
like, causing the respective devices of this capabilty to be added or
removed.
This allows for clients that are temporarily disinterested in a
capability but may require said capability later.
The default function takes one capability, a helper for enable/disable
multiple capabilities in one go is provided as well. On the protocol,
only the "bind" request exists which always represents the currently
wanted set of capabilities.
Note that the helper functions for multiple capabilities require NULL
(not zero) as sentinel, thanks to gcc.
A libei context can be initialized as active or passive context -
an "active" context sends events, a "passive" context receives events.
The EIS context supports both simultaneously, it is up to the
implementation to disconnect libei clients that it does not want to
suppport.
For example, the xdotool use-case creates an active libei context. The
EIS implementation controls and sets up the devices, but libei
sends the events.
In an input-capturing use-case, the EIS implementation controls
and sets up the devices **and** sends the events. libei is merely the
receiver for any event, it cannot send events. Thus this use-case
requires a passive libei context.
Most of this code is copy/paste with minor modifications - libei already
had the code to send events, libeis had the code to receive events, so
the vast majority of this patch is copying the code into the respective
other library, swap "ei" and "eis" and then apply the various minor
modifications needed to hook into the existing library.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
