diff options
Diffstat (limited to 'src/3rdparty/xcb/README')
| -rw-r--r-- | src/3rdparty/xcb/README | 50 |
1 files changed, 47 insertions, 3 deletions
diff --git a/src/3rdparty/xcb/README b/src/3rdparty/xcb/README index 362fa54bf8..af899024c3 100644 --- a/src/3rdparty/xcb/README +++ b/src/3rdparty/xcb/README @@ -8,15 +8,59 @@ The following parts were removed from it: - SendExtensionEvent API (requires definition of xcb_raw_generic_event_t from libxcb 1.13) +The following has been added: + - A fix for forwards compatibility bug with X Server 21.1 (see below) + - Touchpad gesture support (see below) + ***************************************************************** As of time of writing the minimal required libxcb version is 1.11, hence -we could restore the Pointer Barriers API, but we don't use it, so it is -not worth the hustle. When we will bump the minimal required version of libxcb -to 1.13, then we can drop the bundled xcb-xinput altogether. +we could restore the Pointer Barriers API, but we don't use it. +Additionally, we support touchpad gestures which is a much newer addition +to libxcb, but fortunately very well contained. When we will bump the +minimal required version of libxcb to 1.15, then we can drop the bundled +xcb-xinput altogether. The xcb-xinput files where modified to use system includes, see: src/3rdparty/xcb/include/xcb/fixup-xinput-h.patch src/3rdparty/xcb/libxcb/fixup-xinput-c.patch +***************************************************************** + +A forwards compatibility bug in libxcb xinput has been addressed +by the following patch: + +src/3rdparty/xcb/libxcb/xinput-device-class-sizeof.patch + +The crux of the issue is that libxcb thinks that it knows about all device +class types sent by the X server XInput extension. With the addition of +touchpad gestures in XInput 2.4 and X server 21.1 this is no longer the case +and libxcb fails horribly by thinking that the protocol was malformed. + +The X server currently has a workaround, but it would not address the following +situation: + + - there are multiple modules within the same X client (e.g. part of the application + uses Qt, another part talks to X server via another library) + - both of the modules talk to XI + - at least one module requests for XI 2.4 protocol support. + +The request for XI 2.4 disables the workaround on the X server and Qt side would +crash horribly. + +For more details, see https://gitlab.freedesktop.org/xorg/lib/libxcb/-/merge_requests/20 + +***************************************************************** + +Touchpad gestures support has been added in the following patches: + +src/3rdparty/xcb/include/xcb/touchpad-gestures-h.patch +src/3rdparty/xcb/libxcb/touchpad-gestures-c.patch + +The patches were generated by cherry-picking +151ee69847c706e2b9d38c82e20534910f140b55 from xcb-xcbproto master on top of 1.13, +generating xinput.h and xinput.c files and comparing to what would be generated in +vanilla libxcb 1.13 and xcb-proto 1.13. + +For more details, see https://gitlab.freedesktop.org/xorg/proto/xcbproto/-/merge_requests/16 |