Xi: reset the known properties at the end of the server generation.

Properties allocated through XIGetKnownProperty() aren't reset on the second
server generation but keep the old value. As a result, wrong Atoms are
supplied to the driver, resulting in potential data corruption or weird
error message.

Reproducible by running "xlsatom | grep FLOAT" twice on a plain X server.
The second X server generation won't have the FLOAT atom defined anymore,
despite the users of this atom not noticing any errors.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
(cherry picked from commit 9802839d35)

Xi/extinit.c

@@ -1123,6 +1123,7 @@ RestoreExtensionEvents(void)
 static void
 IResetProc(ExtensionEntry * unused)
 {
+    XIResetProperties();
 
     ReplySwapVector[IReqCode] = ReplyNotSwappd;
     EventSwapVector[DeviceValuator] = NotImplemented;

Xi/xiproperty.c

@@ -392,6 +392,15 @@ XIGetKnownProperty(char *name)
     return 0;
 }
 
+void
+XIResetProperties(void)
+{
+    int i;
+
+    for (i = 0; i < (sizeof(dev_properties)/sizeof(struct dev_properties)); i++)
+        dev_properties[i].type = None;
+}
+
 /**
  * Convert the given property's value(s) into @nelem_return integer values and
  * store them in @buf_return. If @nelem_return is larger than the number of

Xi/xiproperty.h

@@ -62,4 +62,7 @@ void SRepXIListProperties(ClientPtr client, int size,
                           xXIListPropertiesReply *rep);
 void SRepXIGetProperty(ClientPtr client, int size,
                        xXIGetPropertyReply *rep);
+
+void XIResetProperties(void);
+
 #endif /* XIPROPERTY_H */