[PATCH inputproto multitouch v2] Touch IDs must be globally unique

Chase Douglas chase.douglas at canonical.com
Mon Dec 12 10:44:08 PST 2011

From: Chase Douglas <cndougla at cndougla.(none)>

XIAllowEvents with a master device and a touch ID must uniquely identify
a touch sequence. If touch IDs were unique per slave device, multiple
slave devices could have valid sequences with the same touch ID, and the
sequences may both be grabbed through the same master device grab.

Signed-off-by: Chase Douglas <chase.douglas at canonical.com>
 specs/XI2proto.txt |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/specs/XI2proto.txt b/specs/XI2proto.txt
index c467bb1..ba5f7b7 100644
--- a/specs/XI2proto.txt
+++ b/specs/XI2proto.txt
@@ -2151,7 +2151,7 @@ Touch tracking IDs are provided in the detail field of touch events. Its
 value is always provided in every touch event. Tracking IDs are
 represented as unsigned 32-bit values and increase in value for each new
 touch, wrapping back to 0 upon reaching the numerical limit of IDs. IDs are
-unique per each slave touch device.
+globally unique.
 Touch events do not generate enter/leave events.

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