wayland: Add experimental pantheon-desktop-shell protocol

This is quite hacky but this open the way to using the pantheon-desktop-shell protocol.

docs/meson.build

@@ -51,6 +51,9 @@ all_doc_target = custom_target(
         '--pkg', 'granite',
         '--pkg', 'gnome-desktop-3.0',
         '--pkg', 'gmodule-2.0',
+        '--pkg', 'wayland-server',
+        '--pkg', 'pantheon-desktop-shell',
+        '--vapidir=' + join_paths(meson.global_source_root(), 'protocol'),
         '-o', '@OUTPUT@',
         '@INPUT@'
     ],

meson.build

@@ -182,6 +182,7 @@ if get_option('systemd')
 endif
 
 subdir('data')
+subdir('protocol')
 subdir('lib')
 subdir('src')
 subdir('daemon')

po/POTFILES

@@ -1,4 +1,5 @@
 src/Dialogs.vala
+src/PantheonShell.vala
 src/ScreenshotManager.vala
 src/WindowManager.vala
 daemon/BackgroundMenu.vala

protocol/meson.build

@@ -0,0 +1,32 @@
+dep_scanner = dependency('wayland-scanner', native: true)
+prog_scanner = find_program(dep_scanner.get_variable(pkgconfig: 'wayland_scanner'))
+
+protocol_file = files('pantheon-desktop-shell-v1.xml')
+
+pantheon_desktop_shell_sources = []
+pantheon_desktop_shell_sources += custom_target(
+	'pantheon-desktop-shell-server-protocol.h',
+	command: [ prog_scanner, 'server-header', '@INPUT@', '@OUTPUT@' ],
+	input: protocol_file,
+	output: 'pantheon-desktop-shell-server-protocol.h',
+)
+
+output_type = 'private-code'
+if dep_scanner.version().version_compare('< 1.14.91')
+    output_type = 'code'
+endif
+pantheon_desktop_shell_sources += custom_target(
+	'pantheon-desktop-shell-protocol.c',
+	command: [ prog_scanner, output_type, '@INPUT@', '@OUTPUT@' ],
+	input: protocol_file,
+	output: 'pantheon-desktop-shell-protocol.c',
+)
+
+pantheon_desktop_shell_dep = declare_dependency(
+    dependencies: [
+        vala.find_library('pantheon-desktop-shell', dirs: meson.current_source_dir()),
+        dependency('wayland-server'),
+    ],
+    include_directories: include_directories('.'),
+    sources: pantheon_desktop_shell_sources
+)

protocol/pantheon-desktop-shell-v1.xml

@@ -0,0 +1,76 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="pantheon_shell_v1">
+  <copyright><![CDATA[
+    SPDX-FileCopyrightText: 2023 Corentin Noël <tintou@noel.tf>
+
+    SPDX-License-Identifier: LGPL-2.1-or-later
+  ]]></copyright>
+
+  <interface name="io_elementary_pantheon_shell_v1" version="1">
+    <description summary="create panel, widget and get more control">
+      This interface is used by the Pantheon Wayland shell to communicate with
+      the compositor.
+    </description>
+
+    <request name="get_panel">
+      <description summary="create a panel surface from a surface">
+        Create a panel surface from an existing surface.
+      </description>
+      <arg name="output" type="new_id" interface="io_elementary_pantheon_panel_v1"/>
+      <arg name="surface" type="object" interface="wl_surface"/>
+    </request>
+
+    <request name="get_widget">
+      <description summary="create a widget surface from a surface">
+        Create a desktop widget surface from an existing surface.
+      </description>
+      <arg name="output" type="new_id" interface="io_elementary_pantheon_widget_v1"/>
+      <arg name="surface" type="object" interface="wl_surface"/>
+    </request>
+
+    <request name="get_extended_behavior">
+      <description summary="create a desktop-specific surface from a surface">
+        Create a desktop-specific surface from an existing surface.
+      </description>
+      <arg name="output" type="new_id" interface="io_elementary_pantheon_extended_behavior_v1"/>
+      <arg name="surface" type="object" interface="wl_surface"/>
+    </request>
+  </interface>
+
+  <interface name="io_elementary_pantheon_panel_v1" version="1">
+    <request name="destroy" type="destructor"/>
+
+    <enum name="anchor">
+      <description summary="anchor">
+        The anchor is a placement hint to the compositor.
+      </description>
+      <entry name="top" value="0" summary="the top edge of the screen"/>
+      <entry name="bottom" value="1" summary="the bottom edge of the screen"/>
+      <entry name="left" value="2" summary="the left edge of the screen"/>
+      <entry name="right" value="3" summary="the right edge of the screen"/>
+    </enum>
+
+    <request name="set_anchor">
+      <description summary="set panel edge anchor">
+        Tell the shell which side of the screen the panel is
+        located. This is so that new windows do not overlap the panel
+        and maximized windows maximize properly.
+      </description>
+
+      <arg name="anchor" type="uint" enum="anchor" summary="anchor"/>
+    </request>
+  </interface>
+
+  <interface name="io_elementary_pantheon_widget_v1" version="1">
+    <request name="destroy" type="destructor"/>
+  </interface>
+
+  <interface name="io_elementary_pantheon_extended_behavior_v1" version="1">
+    <request name="destroy" type="destructor"/>
+    <request name="set_keep_above">
+      <description summary="set keep above">
+        Tell the shell to keep the surface above on all workspaces
+      </description>
+    </request>
+  </interface>
+</protocol>

protocol/pantheon-desktop-shell.deps

@@ -0,0 +1 @@
+wayland-server

protocol/pantheon-desktop-shell.vapi

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2023 elementary, Inc. <https://elementary.io>
+ * Copyright 2023 Corentin Noël <tintou@noel.tf>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+namespace Pantheon.Desktop {
+    [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "struct io_elementary_pantheon_shell_v1_interface")]
+    public struct ShellInterface {
+        [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "io_elementary_pantheon_shell_v1_interface")]
+        public static Wl.Interface iface;
+        public Pantheon.Desktop.GetPanel get_panel;
+        public Pantheon.Desktop.GetWidget get_widget;
+        public Pantheon.Desktop.GetExtendedBehavior get_extended_behavior;
+
+    }
+    [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "enum io_elementary_pantheon_panel_v1_anchor", cprefix="IO_ELEMENTARY_PANTHEON_PANEL_V1_ANCHOR_", has_type_id = false)]
+    public enum Anchor {
+        TOP,
+        BOTTOM,
+        LEFT,
+        RIGHT,
+    }
+
+    [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "struct io_elementary_pantheon_panel_v1_interface")]
+    public struct PanelInterface {
+        [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "io_elementary_pantheon_panel_v1_interface")]
+        public static Wl.Interface iface;
+        public Destroy destroy;
+        public SetAnchor set_anchor;
+    }
+
+    [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "struct io_elementary_pantheon_widget_v1_interface")]
+    public struct WidgetInterface {
+        [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "io_elementary_pantheon_widget_v1_interface")]
+        public static Wl.Interface iface;
+        public Destroy destroy;
+    }
+
+    [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "struct io_elementary_pantheon_extended_behavior_v1_interface")]
+    public struct ExtendedBehaviorInterface {
+        [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "io_elementary_pantheon_extended_behavior_v1_interface")]
+        public static Wl.Interface iface;
+        public Destroy destroy;
+        public SetKeepAbove set_keep_above;
+    }
+
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void GetPanel (Wl.Client client, Wl.Resource resource, uint32 output, Wl.Resource surface);
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void GetWidget (Wl.Client client, Wl.Resource resource, uint32 output, Wl.Resource surface);
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void GetExtendedBehavior (Wl.Client client, Wl.Resource resource, uint32 output, Wl.Resource surface);
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void SetAnchor (Wl.Client client, Wl.Resource resource, [CCode (type = "uint32_t")] Anchor anchor);
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void SetKeepAbove (Wl.Client client, Wl.Resource resource);
+    [CCode (has_target = false, has_typedef = false)]
+    public delegate void Destroy (Wl.Client client, Wl.Resource resource);
+}

src/Main.vala

@@ -76,6 +76,9 @@ namespace Gala {
 
         try {
             ctx.start ();
+            if (ctx.get_compositor_type () == Meta.CompositorType.WAYLAND) {
+                Gala.init_pantheon_shell (ctx);
+            }
         } catch (Error e) {
             stderr.printf ("Failed to start: %s\n", e.message);
             return Posix.EXIT_FAILURE;