From 0d440a1c6e219cd39dbddd2b7e813c6431aac6ea Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Wed, 8 Dec 2010 14:52:19 +1000 Subject: dix: allow for button-only input devices (#21457) Add a few checks for the existence of a valuator class on the device to avoid null-pointer dereferences for button events from devices without a valuator class. X.Org Bug 21457 Signed-off-by: Peter Hutterer Reviewed-by: Chase Douglas Reviewed-by: Daniel Stone --- dix/getevents.c | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/dix/getevents.c b/dix/getevents.c index 9feb2166b..794df420b 100644 --- a/dix/getevents.c +++ b/dix/getevents.c @@ -767,7 +767,7 @@ moveRelative(DeviceIntPtr dev, int *x, int *y, ValuatorMask *mask) /* if attached, clip both x and y to the defined limits (usually * co-ord space limit). If it is attached, we need x/y to go over the * limits to be able to change screens. */ - if(dev->u.master) { + if(dev->u.master && dev->valuator) { if (valuator_get_mode(dev, 0) == Absolute) clipAxis(dev, 0, x); if (valuator_get_mode(dev, 1) == Absolute) @@ -830,7 +830,7 @@ positionSprite(DeviceIntPtr dev, int *x, int *y, float x_frac, float y_frac, int old_screenx, old_screeny; /* scale x&y to screen */ - if (dev->valuator->numAxes > 0) { + if (dev->valuator && dev->valuator->numAxes > 0) { *screenx = rescaleValuatorAxis(*x, x_frac, screenx_frac, dev->valuator->axes + 0, NULL, scr->width); } else { @@ -838,7 +838,7 @@ positionSprite(DeviceIntPtr dev, int *x, int *y, float x_frac, float y_frac, *screenx_frac = dev->last.remainder[0]; } - if (dev->valuator->numAxes > 1) { + if (dev->valuator && dev->valuator->numAxes > 1) { *screeny = rescaleValuatorAxis(*y, y_frac, screeny_frac, dev->valuator->axes + 1, NULL, scr->height); } else { @@ -872,18 +872,21 @@ positionSprite(DeviceIntPtr dev, int *x, int *y, float x_frac, float y_frac, dev->u.master->last.remainder[1] = *screeny_frac; } - /* Crossed screen? Scale back to device coordiantes */ - if(*screenx != old_screenx) + if (dev->valuator) { - scr = miPointerGetScreen(dev); - *x = rescaleValuatorAxis(*screenx, *screenx_frac, &x_frac, NULL, - dev->valuator->axes + 0, scr->width); - } - if(*screeny != old_screeny) - { - scr = miPointerGetScreen(dev); - *y = rescaleValuatorAxis(*screeny, *screeny_frac, &y_frac, NULL, - dev->valuator->axes + 1, scr->height); + /* Crossed screen? Scale back to device coordiantes */ + if(*screenx != old_screenx) + { + scr = miPointerGetScreen(dev); + *x = rescaleValuatorAxis(*screenx, *screenx_frac, &x_frac, NULL, + dev->valuator->axes + 0, scr->width); + } + if(*screeny != old_screeny) + { + scr = miPointerGetScreen(dev); + *y = rescaleValuatorAxis(*screeny, *screeny_frac, &y_frac, NULL, + dev->valuator->axes + 1, scr->height); + } } /* dropy x/y (device coordinates) back into valuators for next event */ @@ -904,6 +907,9 @@ positionSprite(DeviceIntPtr dev, int *x, int *y, float x_frac, float y_frac, static void updateHistory(DeviceIntPtr dev, ValuatorMask *mask, CARD32 ms) { + if (!dev->valuator) + return; + updateMotionHistory(dev, ms, mask, dev->last.valuators); if (dev->u.master) { @@ -1104,7 +1110,7 @@ GetPointerEvents(EventList *events, DeviceIntPtr pDev, int type, int buttons, if (!pDev->enabled) return 0; - if (!scr || !pDev->valuator) + if (!scr) return 0; switch (type) -- cgit v1.2.3