[Linuxwacom-devel] [PATCH] xsetwacom: print an error if the property does not exist on the device.

[Peter H. <pet...@wh...>]

Currently only PressCurve but I guess we'll have more of those soon.

Signed-off-by: Peter Hutterer <pet...@wh...>
---
 tools/xsetwacom.c |   29 +++++++++++++++++++++++++++++
 1 files changed, 29 insertions(+), 0 deletions(-)

diff --git a/tools/xsetwacom.c b/tools/xsetwacom.c
index 59602b4..e1f2753 100644
--- a/tools/xsetwacom.c
+++ b/tools/xsetwacom.c
@@ -945,6 +945,28 @@ static XDevice* find_device(Display *display, char *name)
 	return dev;
 }
 
+/* Return True if the given device has the property, or False otherwise */
+static Bool test_property(Display *dpy, XDevice* dev, Atom prop)
+{
+	int nprops_return;
+	Atom *properties;
+	int found = False;
+
+	properties = XListDeviceProperties(dpy, dev, &nprops_return);
+
+	while(nprops_return--)
+	{
+		if (properties[nprops_return] == prop)
+		{
+			found = True;
+			break;
+		}
+	}
+
+	XFree(properties);
+	return found;
+}
+
 static void list_one_device(Display *dpy, XDeviceInfo *info)
 {
 	static int	wacom_prop = 0;
@@ -1871,6 +1893,13 @@ static void get_presscurve(Display *dpy, XDevice *dev, param_t *param, int argc,
 
 	TRACE("Getting pressure curve for device %ld.\n", dev->device_id);
 
+	if (!test_property(dpy, dev, prop))
+	{
+		fprintf(stderr, "Property '%s' does not exist on device.\n",
+				param->prop_name);
+				return;
+	}
+
 	XGetDeviceProperty(dpy, dev, prop, 0, 1000, False, AnyPropertyType,
 				&type, &format, &nitems, &bytes_after, &data);
 
-- 
1.7.0.1