diff options
| author | Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> | 2015-12-08 18:28:24 +0100 |
|---|---|---|
| committer | Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> | 2015-12-10 17:07:56 +0000 |
| commit | 40c927e7331ea4ac9ca50de48560b700e657cded (patch) | |
| tree | 7a6b6661912b20055abecde1a661fe73061cd241 | |
| parent | 0d54b0f4ddb3ec3e14f39d954eb43b10100bbce9 (diff) | |
XCB: prevent a fp division by zero
For certain devices vci->resolution is zero, which causes a SIGFPE
if FE_INVALID exceptions are enabled. Try to prevent that.
Task-number: QTBUG-42717
Change-Id: I388735f5dfb6218496787dbb74cf0c0f43cc928f
Reviewed-by: Alexander Volkov <a.volkov@rusbitech.ru>
Reviewed-by: Błażej Szczygieł <spaz16@wp.pl>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>
| -rw-r--r-- | src/plugins/platforms/xcb/qxcbconnection_xi2.cpp | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp index 8097cce709..1a123703a5 100644 --- a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp +++ b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp @@ -406,6 +406,9 @@ XInput2TouchDeviceData *QXcbConnection::touchDeviceForId(int id) #endif // XCB_USE_XINPUT22 case XIValuatorClass: { XIValuatorClassInfo *vci = reinterpret_cast<XIValuatorClassInfo *>(classinfo); + // Some devices (mice) report a resolution of 0; they will be excluded later, + // for now just prevent a division by zero + const int vciResolution = vci->resolution ? vci->resolution : 1; if (vci->label == atom(QXcbAtom::AbsMTPositionX)) caps |= QTouchDevice::Position | QTouchDevice::NormalizedPosition; else if (vci->label == atom(QXcbAtom::AbsMTTouchMajor)) @@ -414,16 +417,16 @@ XInput2TouchDeviceData *QXcbConnection::touchDeviceForId(int id) caps |= QTouchDevice::Pressure; else if (vci->label == atom(QXcbAtom::RelX)) { hasRelativeCoords = true; - dev->size.setWidth((vci->max - vci->min) * 1000.0 / vci->resolution); + dev->size.setWidth((vci->max - vci->min) * 1000.0 / vciResolution); } else if (vci->label == atom(QXcbAtom::RelY)) { hasRelativeCoords = true; - dev->size.setHeight((vci->max - vci->min) * 1000.0 / vci->resolution); + dev->size.setHeight((vci->max - vci->min) * 1000.0 / vciResolution); } else if (vci->label == atom(QXcbAtom::AbsX)) { caps |= QTouchDevice::Position; - dev->size.setHeight((vci->max - vci->min) * 1000.0 / vci->resolution); + dev->size.setHeight((vci->max - vci->min) * 1000.0 / vciResolution); } else if (vci->label == atom(QXcbAtom::AbsY)) { caps |= QTouchDevice::Position; - dev->size.setWidth((vci->max - vci->min) * 1000.0 / vci->resolution); + dev->size.setWidth((vci->max - vci->min) * 1000.0 / vciResolution); } break; } |