platformsupport/input: add xkbcommon utilities lib

xcb/eglfs/wayland - all use XKB keyboard configs and APIs. There
is a lot of duplicated and naturally a diverging code. This patch
adds a helper library to avoid all the mentioned problems and unify
feature set between these platforms.

qlibinputkeyboard:

Added a fixup for 2803cdf758dbae1006a0c50300af12dac9f71531. From
spec: "keysyms, when bound to modifiers, affect the rules [..]",
meaning we can't look at keys in isolation, but have to check if
bounding exists in the keymap. This is done by using
xkb_state_mod_name_is_active() API, but that API has its limitations -
https://github.com/xkbcommon/libxkbcommon/issues/88
I will fix this separately in the LTS (5.12) branch.

We need to read the modifier state before the key action. This
patch fixes a regression introduced by aforementioned patch, which
caused modifiers being reported wrongly in QKeyEvent::modifiers().

qtwayland:

Moved toKeysym(QKeyEvent) from qtwayland repository into this library.
For this and other key mapping functionality wayland was duplicating
the key table. All of that will be removed from qtwayland, and calls
will be replaced to use this lib. Adjusted toKeysym() to fix QTBUG-71301.
Qt keys don't map to ASCII codes, so first we need search in our key
table, instead of mapping from unicode.

lookupStringNoKeysymTransformations():

fixed off-by-one error, where we were including terminating NUL in
QString.

Fixes: QTBUG-71301
Task-number: QTBUG-65503
Change-Id: Idfddea5b34ad620235dc08c0b9e5a0669111821a
Reviewed-by: Johan Helsing <johan.helsing@qt.io>

1 files changed, 4 insertions, 1 deletions

diff --git a/src/platformsupport/input/libinput/libinput.pri b/src/platformsupport/input/libinput/libinput.pri
index 476f20c1b8..f80b5f41d9 100644
--- a/src/platformsupport/input/libinput/libinput.pri
+++ b/src/platformsupport/input/libinput/libinput.pri
@@ -14,4 +14,7 @@ QMAKE_USE_PRIVATE += libudev libinput
 
 INCLUDEPATH += $$PWD/../shared
 
-qtConfig(xkbcommon): QMAKE_USE_PRIVATE += xkbcommon
+qtConfig(xkbcommon): {
+    QMAKE_USE_PRIVATE += xkbcommon
+    QT += xkbcommon_support-private
+}