dix: Implement internal gesture state handling

dix/Makefile.am

@@ -23,6 +23,7 @@ libdix_la_SOURCES = 	\
 	extension.c	\
 	gc.c		\
 	getevents.c	\
+	gestures.c	\
 	globals.c	\
 	glyphcurs.c	\
 	grabs.c		\

dix/devices.c

@@ -1670,6 +1670,32 @@ InitTouchClassDeviceStruct(DeviceIntPtr device, unsigned int max_touches,
     return FALSE;
 }
 
+/**
+ * Sets up gesture capabilities on @device.
+ *
+ * @max_touches The maximum number of simultaneous touches, or 0 for unlimited.
+ */
+Bool
+InitGestureClassDeviceStruct(DeviceIntPtr device, unsigned int max_touches)
+{
+    GestureClassPtr g;
+
+    BUG_RETURN_VAL(device == NULL, FALSE);
+    BUG_RETURN_VAL(device->gesture != NULL, FALSE);
+
+    g = calloc(1, sizeof(*g));
+    if (!g)
+        return FALSE;
+
+    g->sourceid = device->id;
+    g->max_touches = max_touches;
+    GestureInitGestureInfo(&g->gesture);
+
+    device->gesture = g;
+
+    return TRUE;
+}
+
 /*
  * Check if the given buffer contains elements between low (inclusive) and
  * high (inclusive) only.

dix/gestures.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright © 2011 Collabra Ltd.
+ * Copyright © 2011 Red Hat, Inc.
+ * Copyright © 2020 Povilas Kanapickas  <povilas@radix.lt>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include "inputstr.h"
+#include "scrnintstr.h"
+#include "dixgrabs.h"
+
+#include "eventstr.h"
+#include "exevents.h"
+#include "exglobals.h"
+#include "inpututils.h"
+#include "eventconvert.h"
+#include "windowstr.h"
+#include "mi.h"
+
+Bool
+GestureInitGestureInfo(GestureInfoPtr gi)
+{
+    memset(gi, 0, sizeof(*gi));
+
+    gi->sprite.spriteTrace = calloc(32, sizeof(*gi->sprite.spriteTrace));
+    if (!gi->sprite.spriteTrace) {
+        return FALSE;
+    }
+    gi->sprite.spriteTraceSize = 32;
+    gi->sprite.spriteTrace[0] = screenInfo.screens[0]->root;
+    gi->sprite.hot.pScreen = screenInfo.screens[0];
+    gi->sprite.hotPhys.pScreen = screenInfo.screens[0];
+
+    return TRUE;
+}

dix/meson.build

@@ -12,6 +12,7 @@ srcs_dix = [
     'eventconvert.c',
     'extension.c',
     'gc.c',
+    'gestures.c',
     'getevents.c',
     'globals.c',
     'glyphcurs.c',