input: add a TouchClassRec to the devices

These structs will be used to store touch-related data, events and
information.

Drivers must call InitTouchClassDeviceStruct to set up a multi-touch capable
device.

Touchpoints for the DDX and the DIX are handled separately - touchpoints
submitted by the driver/DDX will be stored in the DDXTouchPointInfoRec. Once
the touchpoints are processed by the DIX, new TouchPointInfoRecs are created
and stored. This process is already used for pointer events with the
last.valuators field.

Note that this patch does not actually add the generation of touch events,
only the required structs.

TouchListeners are (future) recipients of touch or emulated pointer events.
Each listener is in a state, depending which event they have already
received. The type of listener defines how the listener got to be one.

Co-authored-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/Xi/xiquerydevice.c b/Xi/xiquerydevice.c
index 5f543f620..0879080ad 100644
--- a/Xi/xiquerydevice.c
+++ b/Xi/xiquerydevice.c
@@ -240,6 +240,8 @@ SizeDeviceClasses(DeviceIntPtr dev)
         }
     }
 
+    if (dev->touch)
+        len += sizeof(xXITouchInfo);
 
     return len;
 }
@@ -427,6 +429,31 @@ SwapScrollInfo(DeviceIntPtr dev, xXIScrollInfo* info)
     swapl(&info->increment.frac);
 }
 
+/**
+ * List multitouch information
+ *
+ * @return The number of bytes written into info.
+ */
+int
+ListTouchInfo(DeviceIntPtr dev, xXITouchInfo *touch)
+{
+    touch->type = XITouchClass;
+    touch->length = sizeof(xXITouchInfo) >> 2;
+    touch->sourceid = touch->sourceid;
+    touch->mode = dev->touch->mode;
+    touch->num_touches = dev->touch->num_touches;
+
+    return touch->length << 2;
+}
+
+static void
+SwapTouchInfo(DeviceIntPtr dev, xXITouchInfo* touch)
+{
+    swaps(&touch->type);
+    swaps(&touch->length);
+    swaps(&touch->sourceid);
+}
+
 int GetDeviceUse(DeviceIntPtr dev, uint16_t *attachment)
 {
     DeviceIntPtr master = GetMaster(dev, MASTER_ATTACHED);
@@ -525,6 +552,14 @@ ListDeviceClasses(ClientPtr client, DeviceIntPtr dev,
         total_len += len;
     }
 
+    if (dev->touch)
+    {
+        (*nclasses)++;
+        len = ListTouchInfo(dev, (xXITouchInfo*)any);
+        any += len;
+        total_len += len;
+    }
+
     return total_len;
 }
 
@@ -554,6 +589,10 @@ SwapDeviceInfo(DeviceIntPtr dev, xXIDeviceInfo* info)
             case XIScrollClass:
                 SwapScrollInfo(dev, (xXIScrollInfo*)any);
                 break;
+            case XITouchClass:
+                SwapTouchInfo(dev, (xXITouchInfo*)any);
+                break;
+
         }
 
         any += len * 4;