deepin-screenshot: can't find dxcb Qt plugin

[Mikhail Novosyolov]

[Impact]
The plugin is broken (does not load) since qtbase has been rebuilt with XInput2 support in https://launchpad.net/ubuntu/+source/qtbase-opensource-src/5.12.2+dfsg-4.

[Test Case]
1. Install deepin-screenshot or any other graphical Qt application.
2. Run it with QT_QPA_PLATFORM=dxcb environment variable set.
3. It should run correctly.

[Proposed Fix]
deepin-qt5dxcb-plugin is rebuilt against the current qtbase version.
Build-Dependency on libxcb-xinput-dev is added, otherwise it FTBFS.

[Regression Potential]
I cannot imagine regressions compared to the “does not load” state.

------------------------------------------------------------------------
Original Description

$ deepin-screenshot
qt.qpa.plugin: Could not load the Qt platform plugin "dxcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: wayland-org.kde.kwin.qpa, dxcb, eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.

$ dpkg -S /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libdxcb.so
qt5dxcb-plugin:amd64: /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libdxcb.so

$ LD_PRELOAD=/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libdxcb.so deepin-screenshot
deepin-screenshot: symbol lookup error: /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libdxcb.so: undefined symbol: _ZN22deepin_platform_plugin15WindowEventHook11windowEventEP6QEvent

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: qt5dxcb-plugin 1.1.22-1ubuntu1
ProcVersionSignature: Ubuntu 5.0.0-13.14-generic 5.0.6
Uname: Linux 5.0.0-13-generic x86_64
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
CurrentDesktop: XFCE
Date: Sat Apr 27 09:25:01 2019
InstallationDate: Installed on 2017-08-28 (606 days ago)
InstallationMedia: Xubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
SourcePackage: deepin-qt5dxcb-plugin
UpgradeStatus: Upgraded to disco on 2018-02-08 (442 days ago)
modified.conffile..etc.default.apport:
 # set this to 0 to disable apport, or to 1 to enable it
 # you can temporarily override this with
 # sudo service apport start force_start=1
 enabled=0
mtime.conffile..etc.default.apport: 2018-07-03T12:21:32.224223

[Mikhail Novosyolov (mikhailnov)]

deepin-qt5dxcb-plugin is missing build dependency from libxcb-xinput-dev

[Mikhail Novosyolov (mikhailnov)]

I've built a fix in https://launchpad.net/~mikhailnov/+archive/ubuntu/deepin-screenshot , it seems that just rebuilding deepin-qt5dxcb-plugin will fix this issue.

[Launchpad Janitor (janitor)]

This bug was fixed in the package deepin-qt5dxcb-plugin - 1.1.24-1ubuntu2

---------------
deepin-qt5dxcb-plugin (1.1.24-1ubuntu2) eoan; urgency=medium

  * Build with upstream debian/ directory removed.
  * Build-depend on libxcb-xinput-dev.

 -- Dmitry Shachnev <email address hidden> Sun, 19 May 2019 17:56:53 +0300

[Brian Murray (brian-murray)]

Hello Mikhail, or anyone else affected,

Accepted deepin-qt5dxcb-plugin into disco-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/deepin-qt5dxcb-plugin/1.1.22-1ubuntu1.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-disco to verification-done-disco. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-disco. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Tommy Vercetti (tommyvct)]

Yes, this new proposed package successfully fixed the issue, at least for me, on deepin-music

[Mikhail Novosyolov (mikhailnov)]

It seems to be fixed

[Dmitry Shachnev (mitya57)]

Thanks, marked as verified based on the last two comments.

[Launchpad Janitor (janitor)]

This bug was fixed in the package deepin-qt5dxcb-plugin - 1.1.22-1ubuntu1.1

---------------
deepin-qt5dxcb-plugin (1.1.22-1ubuntu1.1) disco; urgency=medium

  * Rebuild against qtbase ≥ 5.12.2+dfsg-4 (LP: #1826629).
  * Build-depend on libxcb-xinput-dev to fix build failure.

 -- Dmitry Shachnev <email address hidden> Sun, 19 May 2019 18:14:38 +0300

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for deepin-qt5dxcb-plugin has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.