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.
Our API requires a client to know which capability to pass into the
drop_capabilities function. This doesn't work for capabilities newer
than the client's version so they do not get disabled. The client will
thus receive devices it didn't ask for and doesn't know how to handle.
Let's invert the requirement and require the caller to confirm the
capabilities it wants - all others are dropped.
This is an API break but also requires updates of all clients, the
previous simple case of just calling ei_seat_bind() will now result in
zero capabilities.
One macro that also defines the cleanup function, one macro that only
defines the unref. This is required for any place where we want to
use cleanup from multiple source files - like the test suite.
Once a device is removed, it is moved to the seat's devices_removed
list and the seat's ref is dropped - meaning the seat no longer keeps
the device alive. Once the caller's refcounts drop, the device can be
destroyed.
The device still keeps the seat alive though through a ref.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This changes the protocol so that it is the EIS implementation that
creates devices within a seat.
A client now "binds" to a seat and the EIS implementation creates
devices matching the requested capabilities. A client can close a device
if it no longer wants those but otherwise everything (including pointer
ranges) is handled by the server.
This is one giant patch because changes at the protocol level cannot
easily be broken out into smaller patches. Some FIXMEs are left which
will be handled in follow-up patches, e.g. the keymap handling is
basically broken right now.
Fixes#7
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This simplifies the handling of devices that were never added a bit, including
handling the refs between seat and device. And for legitimate use-cases
there's no reason why a caller would create a device but never add it.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Previously we didn't always clean up properly, especially where unexpected
removals happened. So the new approach is:
- the device always has a ref to the seat, we must not remove the seat until
even not-yet-added devices are released
- the seat has a ref to the device *after* it was added. this is a circular
ref so we need to make sure the device is manually removed from the seat
so we can actually reach a refcount 1
This is made slightly more complicated by us calling ei_disconnect() whenever
we fail to write on the fd. The result is re-entrant functions that we need to
protect against inadvertent changes. The best option here is probably to mark
the context as degraded and clean up once we finished whatever we were really
doing - that's a larger rework though.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Removing a seat could cause two device remove events to happen. Fix this by
splitting the removal up into two bits: removed by server and removed by
client. Only once both bits are set, remove the device.
This needs to happen in libei and libeis.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
To cut down on the boilerplate, an unref-able struct variable can now be
declared as
_unref_(type) *name = NULL;
which is the equivalent of
_cleanup_(type_unrefp) struct type *name = NULL;
Let's see how that style ends up reading.
This means we can get rid of the custom _cleanup_foo_ functions everywhere, no
need for all the extra #defines etc. A somewhat special case is systemd which
defines the various unrefp functions for us in the headers, so we can use them
directly.
OBJECT_IMPLEMENT_UNREF now also creates the unrefp function for this object -
this of course conflicts where DECLARE_UNREF_CLEANUP_FUNC is in scope. Not a
problem so far, let's see how we go.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
After CONNECT, the EIS implementation needs to add one or more seats. The
libei client can only create devices within those seats. This mirrors the
wayland hierarchy as well as the X.Org one.
The seat has a set of allowed capabilities, so the client knows ahead of time
when it may not be possible to create a specific device.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
