Our soname tracks the library version, even though on Linux only the
first number is actually being used. The rest is just to make it easier
for tools to find the right version. So let's do that.
And until the 1.0 version is out and our library ABI is stable, hardcode
to 1.0.0
This commit also moves the header define up for better grouping.
This makes it possible to have multiple (incompatible) versions
installed simultaneously.
Any incompatible version requires us bumping the major version, so our
headers are simply installed into the hardcoded libei-1.0 subdir.
This also changes the pkgconfig names to include the API version, so
it's now `pkgconfig --cflags libei-1.0`.
`memfd_create` doesn't seem to be supported on
all platforms (e.g. ubuntu 18 has trouble with it).
Even though, I was able to substitute `memfd_create`
with a direct system call, I was not able to get
the `MFD_CLOXEC` flag (from fcntl.h) working cleanly
(there were redefinitions/conflicts for other
structures when trying to use <linux/*> headers).
Making it optional for time being till we have
figured out how to make it work broadly.
We still have the separate CI jobs for those (for better visibility) but
also optionally incorporate those into the meson test run.
Both calls only check the files, they do not modify anything.
This tests the protocol layer which is hard to test using libei/libeis.
Similar to the generated C bindings we compile a eiproto.py file that is
then used in the test to talk protocol directly to the eis-demo-server
that we start up.
By sending the specific messages and checking things happen as we expect
on the socket we can verify that the EIS implementation is correct (and
robust enough).
In theory this could also be used to test some other binary with an EIS
implementation and the scaffolding is there to set LIBEI_TEST_SERVER to
that binary. Wether this works is untested though...
Leave the ei_callback as-is and instead add ei_pingpong for the same
thing initiated by the server. The interface is otherwise identical but
for the direction it is supposed to flow.
This reduces the possibility of a client accidentally sending a
request when it is supposed to handle an event or vice versa.
This allows us to have a device support multiple interfaces and evolve
those interfaces individually, e.g. add things to the keyboard interface
without having to bump the touchscreen interface.
Note that due to a name clash with the existing struct ei_touch public
API the protocol interface is named touchscreen.
This replaces the connect/connect_done and version/get_version requests.
Immediately after connecting, the server sends an ei_protocol_setup
event to the client with the ID of the object and the server's highest
supported version number (of this object).
This is a one-shot object that the client can use to configure its name
and whether it is a sender or receiver context. Once .done is sent, the
object is discarded.
The server version is sent along to the client to allow for requests to
be added to this object in the future.
As a fixme left: the client now assumes to be connected as soon as the
.done request is sent and the following sync event is received. The
EIS implementation will not have actually eis_client_connect()ed the
client yet, but it's good enough for now.
Arguably, the CONNECTED event is superfluous anyway since *any* event
other than DISCONNECTED indicates connected status. CONNECTED is a
leftover from when the client created devices and needed to know if it's
worth doing so.
Directly copied from wayland. Note that while the wayland protocol
specifies the data is the last event serial in our case here it's just
0 since we don't have any event serials (yet).
The sync request is currently triggered after connection, merely to
ensure it works, it's not actually needed.
In the protocol this is a simple rename but in the implementation we can
now separate the protocol object out from the ei/ei-client context
itself by having the ei_connection objects.
This protocol is wayland-like though it uses a slightly different
message format. The XML file uses the same structure, except for the
"fixed" type which is "float" here.
The scanner uses a jinja template to generate source and header files
for ei and eis which are now used instead of the protobuf-generated
objects. Note that the scanner is a minimal working version, some
features like enum value checks are not yet implemented.
Unlike wayland we do not need to generate the libwayland-like library,
we only need the wire protocol parser - some shortcuts can thus be taken.
To keep the changes simple, the protocol currently is a flat protocol
with only one interface and all messages copied over from the previous
ei.proto file. In future commits, this will be moved to the respective
interfaces instead.
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.
libei used to have direct portal support code (see the git history) but:
- that code was a custom proposed portal that never went anywhere
- libei has slowly changed to be more an input event transport layer since
it is now also used sending events *to* a libei context
- a number of libei users will never need the DBus code, either because they
don't want it or because they talk Dbus themselves na ddon't need this
abstraction.
Luckily, it's quite easy to move this into a separate library with a
simple API that does, effectively, the same trick as the old portal backend.
This API is aiming to be as simple as possible because the tools that
require anything more complex should talk to DBus directly.
An example tool that uses the API to retrieve an EIS fd over the
RemoteDesktop portal is included in this patch.
"Öffis" is a German word meaning public transport. It also sounds like the
French Œuf, the word for egg.
Co-authored-by: Olivier Fourdan <ofourdan@redhat.com>
The original idea here was that we would have an EmulatedInput portal
that allows the application to connect directly to the EIS
implementation to exchange input events - instead of ping-ponging DBus
events through the xdg-desktop-portal as the RemoteDesktop portal
requires.
This is no longer accurate, there are suggested PRs open to add
RemoteDesktop.ConnectToEIS to achieve the same through the existing
RemoteDesktop interface [1] and to add a new InputCapture portal
to allow for events to be sent to a libei receiver context [2].
The example EmulatedInput portal is thus superfluous and can be removed
from here.
We could switch the ei_setup_backend_portal() code to use RemoteDesktop
or InputCapture, depending on the context type, the utility of this is
questionable. Interaction with portals is complex, one needs to
implement the Session/Request interfaces correctly and in the case of
InputCapture also handle the complex zones/pointer barrier setup.
libportal does some of this (or it will, anyway) so it's more useful for
an application to use libportal and then just pass the received fd to
libei.
If there is a future need for this to be handled as part of libei, we
can (re)implement this, but for now it's best to just purge all of this.
[1] https://github.com/flatpak/xdg-desktop-portal/pull/762
[2] https://github.com/flatpak/xdg-desktop-portal/pull/714
The same socket is used for pre-connection configuration by a portal and
for the actual client that then uses the data. The portal and the client
may need different protocol versions *and* there may be different REIS
intermediaries.
So let's allow version negotiation for the configuration through
transactions: a REIS intermediary must start/finish a transaction with a
given version number.
This is only partially implemented in libreis right now: each API call
is wrapped in a transaction. Since we support version 1 only anyway,
there's no need to do anything but send our version down the wire. In
the future where we actually need to negotiate, libreis will need a
reis_dispatch() so we can wait for the server version to arrive, parse
it, etc. before sending ConfigureVersion down the wire. It's likely this
will never be needed.
Add a new protocol message "GetVersion" and the matching reply from the
server with "Version" that can be sent at any time. The server always
replies with the highest protocol version it supports, allowing the
client to choose the protocol version it wants.
These two messages also have a fixed string to make the protocol easy to
identify in hexdumps.
To avoid roundtrips on connection, libeis immediately sends the Version
message. Ideally and by the time the client actually starts, that
version is already available and we can continue without requiring a
full roundtrip.
This patch only adds the version exchange with the server, it does not
yet add the bits for the client to actually set the version.
The basic set of functions and macros to have access to a libreis
context for our to-be-client.
Since we connect the ei context to a backend during peck_new(), we need
a new function for the case where we do want to have libreis in the
mix.