Bug 542865: [GTK4] Snippets with any children of Shell crash upon

gtk_widget_get_surface_allocation()

GTK4 no longer supports "own" surfaces for widgets, so this patch
removes this logic from the GTK4 SwtFixed implementation.

Some adjustments have to made in Control, as we do
gtk_widget_get_has_surface_or_window() checks to determine the
paintHandle. In GTK4 this is broken so always use the surface of the
fixedHandle (or clientHandle in the case of Group).

Change-Id: I09c0c096407ab67ac10edfcd21a3c9927cb5f833
Signed-off-by: Eric Williams <ericwill@redhat.com>

5 files changed, 51 insertions, 3 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_custom.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_custom.c
index 91ef301f78..d46a299e88 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_custom.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_custom.c
@@ -780,7 +780,6 @@ static void swt_fixed_class_init (SwtFixedClass *class) {
 	g_object_class_override_property (gobject_class, PROP_VSCROLL_POLICY, "vscroll-policy");
 
 	/* Widget implementation */
-	widget_class->realize = swt_fixed_realize;
 	widget_class->map = swt_fixed_map;
 	widget_class->measure = swt_fixed_measure;
 	widget_class->size_allocate = swt_fixed_size_allocate;
@@ -850,7 +849,7 @@ static void swt_fixed_init (SwtFixed *widget) {
 	priv->hadjustment = NULL;
 	priv->vadjustment = NULL;
 
-	gtk_widget_set_has_surface(GTK_WIDGET(widget), TRUE);
+	gtk_widget_set_has_surface(GTK_WIDGET(widget), FALSE);
 }
 
 static void swt_fixed_finalize (GObject *object) {
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
index 58d2ed9f8a..799ee5e0c7 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
@@ -492,6 +492,7 @@ long /*int*/ topHandle() {
 
 long /*int*/ paintHandle () {
 	long /*int*/ topHandle = topHandle ();
+	if (GTK.GTK4) return topHandle;
 	long /*int*/ paintHandle = handle;
 	while (paintHandle != topHandle) {
 		if (gtk_widget_get_has_surface_or_window (paintHandle)) break;
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Group.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Group.java
index 78818cf2d7..6a6653aac2 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Group.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Group.java
@@ -452,6 +452,7 @@ long /*int*/ paintHandle() {
 	if (GTK.GTK_VERSION < OS.VERSION(3, 14, 0)) {
 		return super.paintHandle();
 	} else {
+		if (GTK.GTK4) return clientHandle;
 		long /*int*/ topHandle = topHandle ();
 		/* we draw all our children on the clientHandle*/
 		long /*int*/ paintHandle = clientHandle;
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
index 525397d7ce..d513ffd15f 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
@@ -816,7 +816,11 @@ void createHandle (int index) {
 	if (vboxHandle == 0) error (SWT.ERROR_NO_HANDLES);
 	createHandle (index, false, true);
 	GTK.gtk_container_add (vboxHandle, scrolledHandle);
-	GTK.gtk_box_set_child_packing (vboxHandle, scrolledHandle, true, true, 0, GTK.GTK_PACK_END);
+	if (GTK.GTK4) {
+		GTK.gtk_box_set_child_packing(vboxHandle, scrolledHandle, GTK.GTK_PACK_END);
+	} else {
+		GTK.gtk_box_set_child_packing (vboxHandle, scrolledHandle, true, true, 0, GTK.GTK_PACK_END);
+	}
 	group = GTK.gtk_window_group_new ();
 	if (group == 0) error (SWT.ERROR_NO_HANDLES);
 	/*
diff --git a/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug542865_ShellChildrenCrash.java b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug542865_ShellChildrenCrash.java
new file mode 100644
index 0000000000..3c56a706e0
--- /dev/null
+++ b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug542865_ShellChildrenCrash.java
@@ -0,0 +1,43 @@
+/*******************************************************************************
+ * Copyright (c) 2018 Red Hat and others. All rights reserved.
+ * The contents of this file are made available under the terms
+ * of the GNU Lesser General Public License (LGPL) Version 2.1 that
+ * accompanies this distribution (lgpl-v21.txt).  The LGPL is also
+ * available at http://www.gnu.org/licenses/lgpl.html.  If the version
+ * of the LGPL at http://www.gnu.org is different to the version of
+ * the LGPL accompanying this distribution and there is any conflict
+ * between the two license versions, the terms of the LGPL accompanying
+ * this distribution shall govern.
+ *
+ * Contributors:
+ *     Red Hat - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.swt.tests.gtk.snippets;
+
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.layout.RowLayout;
+/*
+ * example snippet: Hello World
+ *
+ * For a list of all SWT example snippets see
+ * http://www.eclipse.org/swt/snippets/
+ */
+import org.eclipse.swt.widgets.Button;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Shell;
+
+public class Bug542865_ShellChildrenCrash {
+
+public static void main (String [] args) {
+	Display display = new Display ();
+	Shell shell = new Shell(display);
+	shell.setLayout(new RowLayout());
+	Button button = new Button (shell, SWT.PUSH);
+	button.setText("Test push button");
+	shell.open ();
+	while (!shell.isDisposed ()) {
+		if (!display.readAndDispatch ()) display.sleep ();
+	}
+	display.dispose ();
+}
+}