Implement basic xdg decoration management

src/c.zig

@@ -17,6 +17,7 @@ pub const c = @cImport({
     @cInclude("wlr/types/wlr_pointer.h");
     @cInclude("wlr/types/wlr_seat.h");
     @cInclude("wlr/types/wlr_xcursor_manager.h");
+    @cInclude("wlr/types/wlr_xdg_decoration_v1.h");
     @cInclude("wlr/types/wlr_xdg_shell.h");
     @cInclude("wlr/util/log.h");
     @cInclude("xkbcommon/xkbcommon.h");

src/decoration.zig

@@ -0,0 +1,37 @@
+const std = @import("std");
+const c = @import("c.zig").c;
+
+const DecorationManager = @import("decoration_manager.zig").DecorationManager;
+
+// TODO: this needs to listen for destroy and free nodes from the deco list
+pub const Decoration = struct {
+    const Self = @This();
+
+    decoration_manager: *DecorationManager,
+    wlr_xdg_toplevel_decoration: *c.wlr_xdg_toplevel_decoration_v1,
+
+    listen_request_mode: c.wl_listener,
+
+    pub fn init(
+        self: *Self,
+        decoration_manager: *DecorationManager,
+        wlr_xdg_toplevel_decoration: *c.wlr_xdg_toplevel_decoration_v1,
+    ) void {
+        self.decoration_manager = decoration_manager;
+        self.wlr_xdg_toplevel_decoration = wlr_xdg_toplevel_decoration;
+
+        self.listen_request_mode.notify = handleRequestMode;
+        c.wl_signal_add(&self.wlr_xdg_toplevel_decoration.events.request_mode, &self.listen_request_mode);
+
+        handleRequestMode(&self.listen_request_mode, self.wlr_xdg_toplevel_decoration);
+    }
+
+    fn handleRequestMode(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
+        const decoration = @fieldParentPtr(Decoration, "listen_request_mode", listener.?);
+        // TODO: we might need to take this configure serial and do a transaction
+        _ = c.wlr_xdg_toplevel_decoration_v1_set_mode(
+            decoration.wlr_xdg_toplevel_decoration,
+            c.wlr_xdg_toplevel_decoration_v1_mode.WLR_XDG_TOPLEVEL_DECORATION_V1_MODE_SERVER_SIDE,
+        );
+    }
+};

src/decoration_manager.zig

@@ -0,0 +1,45 @@
+const std = @import("std");
+const c = @import("c.zig").c;
+
+const Decoration = @import("decoration.zig").Decoration;
+const Server = @import("server.zig").Server;
+
+pub const DecorationManager = struct {
+    const Self = @This();
+
+    server: *Server,
+
+    wlr_xdg_decoration_manager: *c.wlr_xdg_decoration_manager_v1,
+
+    decorations: std.SinglyLinkedList(Decoration),
+
+    listen_new_toplevel_decoration: c.wl_listener,
+
+    pub fn init(self: *Self, server: *Server) !void {
+        self.server = server;
+        self.wlr_xdg_decoration_manager = c.wlr_xdg_decoration_manager_v1_create(server.wl_display) orelse
+            return error.CantCreateWlrXdgDecorationManager;
+
+        self.listen_new_toplevel_decoration.notify = handleNewToplevelDecoration;
+        c.wl_signal_add(
+            &self.wlr_xdg_decoration_manager.events.new_toplevel_decoration,
+            &self.listen_new_toplevel_decoration,
+        );
+    }
+
+    fn handleNewToplevelDecoration(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
+        const decoration_manager = @fieldParentPtr(
+            DecorationManager,
+            "listen_new_toplevel_decoration",
+            listener.?,
+        );
+        const wlr_xdg_toplevel_decoration = @ptrCast(
+            *c.wlr_xdg_toplevel_decoration_v1,
+            @alignCast(@alignOf(*c.wlr_xdg_toplevel_decoration_v1), data),
+        );
+
+        const node = decoration_manager.decorations.allocateNode(decoration_manager.server.allocator) catch unreachable;
+        node.data.init(decoration_manager, wlr_xdg_toplevel_decoration);
+        decoration_manager.decorations.prepend(node);
+    }
+};

src/server.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const c = @import("c.zig").c;
 
+const DecorationManager = @import("decoration_manager.zig").DecorationManager;
 const Output = @import("output.zig").Output;
 const Root = @import("root.zig").Root;
 const Seat = @import("seat.zig").Seat;
@@ -11,16 +12,17 @@ pub const Server = struct {
 
     allocator: *std.mem.Allocator,
 
-    root: Root,
-    seat: Seat,
-
     wl_display: *c.wl_display,
     wlr_backend: *c.wlr_backend,
     wlr_renderer: *c.wlr_renderer,
 
-    listen_new_output: c.wl_listener,
-
     wlr_xdg_shell: *c.wlr_xdg_shell,
+
+    decoration_manager: DecorationManager,
+    root: Root,
+    seat: Seat,
+
+    listen_new_output: c.wl_listener,
     listen_new_xdg_surface: c.wl_listener,
 
     pub fn init(self: *Self, allocator: *std.mem.Allocator) !void {
@@ -58,6 +60,8 @@ pub const Server = struct {
         self.wlr_xdg_shell = c.wlr_xdg_shell_create(self.wl_display) orelse
             return error.CantCreateWlrXdgShell;
 
+        try self.decoration_manager.init(self);
+
         try self.root.init(self);
 
         try self.seat.init(self);