events: add support for switch events by muhammad23012009 · Pull Request #4948 · canonical/mir

muhammad23012009 · 2026-05-17T21:28:53Z

currently these events are not handled by Mir itself. QtMir is the only user, with an event filter to steal these switch events.

What's new?

Adds support for processing switch events from libinput

Checklist

Tests added and pass
Adequate documentation added
(optional) Added Screenshots or videos

Copilot

Pull request overview

Adds first-class handling of libinput “switch” events (e.g. tablet-mode toggles) to Mir, so these events can be converted into Mir input events and surfaced through the public toolkit API instead of being intercepted only by downstream consumers (e.g. QtMir).

Changes:

Introduces MirSwitchEvent plus new toolkit enums/accessors for switch action/state.
Extends the input event builder + event factory code to construct switch events and exports the new symbols.
Adds libinput evdev handling for LIBINPUT_EVENT_SWITCH_TOGGLE and threads the new input-event type through a few server components’ input-type switches.

Reviewed changes

Copilot reviewed 22 out of 23 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
tests/unit-tests/input/evdev/test_libinput_device.cpp	Extends the test event-builder mock for switch events (but no new switch tests yet).
src/server/shell/decoration/input.cpp	Ignores switch input events in decoration input handling.
src/server/shell/abstract_shell.cpp	Explicitly returns `false` for switch input events.
src/server/input/idle_poking_dispatcher.cpp	Ensures switch events don’t poke the idle timer.
src/server/input/default_event_builder.h	Adds `switch_event()` to `DefaultEventBuilder`.
src/server/input/default_event_builder.cpp	Implements `DefaultEventBuilder::switch_event()`.
src/server/frontend_xwayland/xwayland_surface_observer.cpp	Treats switch events as non-move/resize events.
src/platforms/evdev/libinput_device.h	Declares switch-event conversion method.
src/platforms/evdev/libinput_device.cpp	Handles `LIBINPUT_EVENT_SWITCH_TOGGLE` and converts tablet-mode toggles.
src/common/symbols.map	Exports new switch event C API + factory symbol.
src/common/input/input_event.cpp	Adds switch input-type string + toolkit accessors for switch events.
src/common/events/switch_event.cpp	Implements the new `MirSwitchEvent` type.
src/common/events/input_event.cpp	Adds `to_switch()` casting helpers.
src/common/events/event_private.h	Pulls in the new switch event definition for internal event plumbing.
src/common/events/event_builders.cpp	Adds `make_switch_event()` factory.
src/common/events/CMakeLists.txt	Builds the new `switch_event.cpp`.
include/platform/mir/input/event_builder.h	Adds `EventBuilder::switch_event()` API.
include/core/mir_toolkit/events/enums.h	Adds `mir_input_event_type_switch` and switch action/state enums.
include/common/mir/events/switch_event.h	Adds internal C++ `MirSwitchEvent` header.
include/common/mir/events/input_event.h	Adds `to_switch()` declarations.
include/common/mir/events/event_builders.h	Declares `make_switch_event()` factory.
include/common/mir_toolkit/events/input/switch_event.h	Adds toolkit header for switch event accessors.
include/common/mir_toolkit/events/input/input_event.h	Exposes `mir_input_event_get_switch_event()` in the toolkit API.

+mir::EventUPtr mie::LibInputDevice::convert_switch_event(libinput_event_switch* switch_event)
+{
+    auto const libinput_switch_type = libinput_event_switch_get_switch(switch_event);
+    auto const libinput_switch_state = libinput_event_switch_get_switch_state(switch_event);
+
+    switch (libinput_switch_type)
+    {
+        case LIBINPUT_SWITCH_TABLET_MODE:
+            return builder->switch_event(
+                mir_switch_action_tablet_mode,
+                libinput_switch_state == LIBINPUT_SWITCH_STATE_ON ? mir_switch_state_on : mir_switch_state_off);
+        default:
+            return {nullptr, [](auto){}};
+    }


        std::optional<Timestamp> timestamp,
        std::vector<mir::events::TouchContact> const& contacts) = 0;

+    virtual EventUPtr switch_event(


+mir::EventUPtr mev::make_switch_event(
+    MirInputDeviceId device_id,
+    MirSwitchAction action,
+    MirSwitchState state)
+{
+    auto e = new_event<MirSwitchEvent>(device_id);
+    e->set_action(action);
+    e->set_state(state);
+
+    return make_uptr_event(e);
+}


+    if(ev->input_type() != mir_input_event_type_switch)
+    {
+        mir::fatal_error_abort("expected switch input event but event was of type ",
+            input_event_type_to_c_str(ev->input_type()));
+    }


+#ifndef MIR_COMMON_SWITCH_EVENT_H_
+#define MIR_COMMON_SWITCH_EVENT_H_
+
+#include <mir/events/input_event.h>
+


+#ifndef MIR_TOOLKIT_SWITCH_EVENT_H_
+#define MIR_TOOLKIT_SWITCH_EVENT_H_
+
+#include <mir_toolkit/events/input/input_event.h>
+


+#include <mir/events/input_event.h>
+#include <mir/events/switch_event.h>
+


        BOOST_THROW_EXCEPTION(std::logic_error("deprecated event builder method called"));
    }
+
+    MOCK_METHOD(mir::EventUPtr, switch_event, (MirSwitchAction, MirSwitchState), ());


+    MirSwitchAction action,
+    MirSwitchState state);


AlanGriffiths

The approach looks sensible.

Copilot has identified a bunch of housekeeping (missing license headers, builder parameters etc). These need addressing. (Technically, copyright doesn't need to be assigned to Canonical as long as the CLA is in place.)

This does involve ABI breakages, so we also need to bump .sonames etc. (but the Mir team can deal with that separately.)

There are, however, parallel APIs in libmiral (include/miral/miral/toolkit_event.h) and, potentially, libmiroil (include/miroil/miroil/input_device.h) that need to reflect these changes.

AlanGriffiths · 2026-05-19T09:11:20Z

    mir_input_event_type_touch = 1,
    mir_input_event_type_pointer = 2,
    mir_input_event_type_keyboard_resync = 3,
+    mir_input_event_type_switch = 4,


FLAGGING FOR ATTENTION: Extending this switch is an ABI break: downstream code needs to be recompiled. (That's not blocking this PR, but we need to do deal with it before a release.)

AlanGriffiths · 2026-05-19T09:15:04Z

        std::optional<Timestamp> timestamp,
        std::vector<mir::events::TouchContact> const& contacts) = 0;

+    virtual EventUPtr switch_event(


FLAGGING FOR ATTENTION: Adding a virtual function to this interface is an ABI break: downstream code needs to be recompiled and implement this function. (That's not blocking this PR, but we need to do deal with it before a release.)

Note also: as we're breaking ABI, there's a bunch of [[deprecated]] functions we can get rid of.

* currently these events are not handled by Mir itself. QtMir is the only user, with an event filter to steal these switch events. Signed-off-by: Muhammad <thevancedgamer@mentallysanemainliners.org>

Signed-off-by: Muhammad <thevancedgamer@mentallysanemainliners.org>

Copilot AI review requested due to automatic review settings May 17, 2026 21:28

Copilot started reviewing on behalf of muhammad23012009 May 17, 2026 21:29 View session

Copilot AI reviewed May 17, 2026

View reviewed changes

AlanGriffiths requested changes May 19, 2026

View reviewed changes

muhammad23012009 and others added 3 commits May 21, 2026 14:41

events: add support for switch events

fb02582

* currently these events are not handled by Mir itself. QtMir is the only user, with an event filter to steal these switch events. Signed-off-by: Muhammad <thevancedgamer@mentallysanemainliners.org>

pre-commit: apply automatic fixes

bcde298

libinput_device: only handle switch event if it's valid

07c6a8c

Signed-off-by: Muhammad <thevancedgamer@mentallysanemainliners.org>

muhammad23012009 force-pushed the main branch from 41f20d6 to 07c6a8c Compare May 21, 2026 09:42

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events: add support for switch events#4948

events: add support for switch events#4948
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muhammad23012009 commented May 17, 2026

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		#include <mir/events/input_event.h>
		#include <mir/events/switch_event.h>

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muhammad23012009 commented May 17, 2026

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