Add Root struct

Server handles listening for wayland signals. It delegates input handling
to Seat and output handling to Root.

src/cursor.zig

@@ -89,7 +89,7 @@ pub const Cursor = struct {
             .resize_edges = 0,
         };
 
-        c.wlr_cursor_attach_output_layout(cursor.wlr_cursor, seat.server.wlr_output_layout);
+        c.wlr_cursor_attach_output_layout(cursor.wlr_cursor, seat.server.root.wlr_output_layout);
         _ = c.wlr_xcursor_manager_load(cursor.wlr_xcursor_manager, 1);
 
         return cursor;
@@ -184,7 +184,7 @@ pub const Cursor = struct {
         var sx: f64 = undefined;
         var sy: f64 = undefined;
         var opt_surface: ?*c.wlr_surface = null;
-        const view = self.seat.server.desktop_view_at(
+        const view = self.seat.server.root.viewAt(
             self.wlr_cursor.x,
             self.wlr_cursor.y,
             &opt_surface,
@@ -278,7 +278,7 @@ pub const Cursor = struct {
         var sy: f64 = undefined;
 
         var surface: ?*c.wlr_surface = null;
-        const view = cursor.seat.server.desktop_view_at(
+        const view = cursor.seat.server.root.viewAt(
             cursor.wlr_cursor.x,
             cursor.wlr_cursor.y,
             &surface,

src/main.zig

@@ -8,11 +8,10 @@ pub fn main() !void {
 
     c.wlr_log_init(c.enum_wlr_log_importance.WLR_DEBUG, null);
 
-    var server = try Server.create(std.heap.c_allocator);
+    var server: Server = undefined;
+    try server.init(std.heap.c_allocator);
     defer server.destroy();
 
-    try server.init();
-
     try server.start();
 
     // Spawn an instance of alacritty

src/output.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const c = @import("c.zig").c;
 
+const Root = @import("root.zig").Root;
 const Server = @import("server.zig").Server;
 const View = @import("view.zig").View;
 
@@ -14,11 +15,11 @@ const RenderData = struct {
 pub const Output = struct {
     const Self = @This();
 
-    server: *Server,
+    root: *Root,
     wlr_output: *c.wlr_output,
     listen_frame: c.wl_listener,
 
-    pub fn init(self: *Self, server: *Server, wlr_output: *c.wlr_output) !void {
+    pub fn init(self: *Self, root: *Root, wlr_output: *c.wlr_output) !void {
         // Some backends don't have modes. DRM+KMS does, and we need to set a mode
         // before we can use the output. The mode is a tuple of (width, height,
         // refresh rate), and each monitor supports only a specific set of modes. We
@@ -27,6 +28,7 @@ pub const Output = struct {
 
         // if not empty
         if (c.wl_list_empty(&wlr_output.modes) == 0) {
+            // TODO: handle failure
             const mode = c.wlr_output_preferred_mode(wlr_output);
             c.wlr_output_set_mode(wlr_output, mode);
             c.wlr_output_enable(wlr_output, true);
@@ -35,7 +37,7 @@ pub const Output = struct {
             }
         }
 
-        self.server = server;
+        self.root = root;
         self.wlr_output = wlr_output;
 
         // Sets up a listener for the frame notify event.
@@ -46,7 +48,7 @@ pub const Output = struct {
         // from left-to-right in the order they appear. A more sophisticated
         // compositor would let the user configure the arrangement of outputs in the
         // layout.
-        c.wlr_output_layout_add_auto(server.wlr_output_layout, wlr_output);
+        c.wlr_output_layout_add_auto(root.wlr_output_layout, wlr_output);
 
         // Creating the global adds a wl_output global to the display, which Wayland
         // clients can see to find out information about the output (such as
@@ -58,7 +60,7 @@ pub const Output = struct {
         // This function is called every time an output is ready to display a frame,
         // generally at the output's refresh rate (e.g. 60Hz).
         const output = @fieldParentPtr(Output, "listen_frame", listener.?);
-        const renderer = output.server.wlr_renderer;
+        const renderer = output.root.server.wlr_renderer;
 
         var now: c.struct_timespec = undefined;
         _ = c.clock_gettime(c.CLOCK_MONOTONIC, &now);
@@ -79,7 +81,7 @@ pub const Output = struct {
 
         // Each subsequent view is rendered on top of the last.
         // The first view in the list is "on top" so iterate in reverse.
-        var it = output.server.views.last;
+        var it = output.root.views.last;
         while (it) |node| : (it = node.prev) {
             const view = &node.data;
             if (!view.mapped) {
@@ -136,7 +138,7 @@ pub const Output = struct {
         // output-local coordinates, or (2000 - 1920).
         var ox: f64 = 0.0;
         var oy: f64 = 0.0;
-        c.wlr_output_layout_output_coords(view.server.wlr_output_layout, output, &ox, &oy);
+        c.wlr_output_layout_output_coords(view.root.wlr_output_layout, output, &ox, &oy);
         ox += @intToFloat(f64, view.x + sx);
         oy += @intToFloat(f64, view.y + sy);
 

src/root.zig

@@ -0,0 +1,62 @@
+const std = @import("std");
+const c = @import("c.zig").c;
+
+const Output = @import("output.zig").Output;
+const Server = @import("server.zig").Server;
+const Seat = @import("seat.zig").Seat;
+const View = @import("view.zig").View;
+
+/// Responsible for all windowing operations
+pub const Root = struct {
+    const Self = @This();
+
+    server: *Server,
+
+    wlr_output_layout: *c.wlr_output_layout,
+    outputs: std.TailQueue(Output),
+
+    // Must stay ordered, first N views in list are the masters
+    views: std.TailQueue(View),
+
+    pub fn init(self: *Self, server: *Server) !void {
+        self.server = server;
+
+        // Create an output layout, which a wlroots utility for working with an
+        // arrangement of screens in a physical layout.
+        self.wlr_output_layout = c.wlr_output_layout_create() orelse
+            return error.CantCreateWlrOutputLayout;
+        errdefer c.wlr_output_layout_destroy(self.wlr_output_layout);
+
+        self.outputs = std.TailQueue(Output).init();
+        self.views = std.TailQueue(View).init();
+    }
+
+    pub fn destroy(self: *Self) void {
+        c.wlr_output_layout_destroy(self.wlr_output_layout);
+    }
+
+    pub fn addOutput(self: *Self, wlr_output: *c.wlr_output) void {
+        // TODO: Handle failure
+        const node = self.outputs.allocateNode(self.server.allocator) catch unreachable;
+        node.data.init(self, wlr_output) catch unreachable;
+        self.outputs.append(node);
+    }
+
+    pub fn addView(self: *Self, wlr_xdg_surface: *c.wlr_xdg_surface) void {
+        const node = self.views.allocateNode(self.server.allocator) catch unreachable;
+        node.data.init(self, wlr_xdg_surface);
+        self.views.append(node);
+    }
+
+    /// Finds the top most view under the output layout coordinates lx, ly
+    /// returns the view if found, and a pointer to the wlr_surface as well as the surface coordinates
+    pub fn viewAt(self: *Self, lx: f64, ly: f64, surface: *?*c.wlr_surface, sx: *f64, sy: *f64) ?*View {
+        var it = self.views.last;
+        while (it) |node| : (it = node.prev) {
+            if (node.data.isAt(lx, ly, surface, sx, sy)) {
+                return &node.data;
+            }
+        }
+        return null;
+    }
+};

src/server.zig

@@ -2,6 +2,7 @@ const std = @import("std");
 const c = @import("c.zig").c;
 
 const Output = @import("output.zig").Output;
+const Root = @import("root.zig").Root;
 const Seat = @import("seat.zig").Seat;
 const View = @import("view.zig").View;
 
@@ -10,91 +11,71 @@ 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,
 
-    wlr_output_layout: *c.wlr_output_layout,
-    outputs: std.TailQueue(Output),
-
     listen_new_output: c.wl_listener,
 
     wlr_xdg_shell: *c.wlr_xdg_shell,
     listen_new_xdg_surface: c.wl_listener,
 
-    // Must stay ordered, first in list is "on top" visually
+    pub fn init(self: *Self, allocator: *std.mem.Allocator) !void {
-    views: std.TailQueue(View),
+        self.allocator = allocator;
-
-    seat: Seat,
-
-    pub fn create(allocator: *std.mem.Allocator) !Self {
-        var server: Self = undefined;
-        server.allocator = allocator;
 
         // The Wayland display is managed by libwayland. It handles accepting
         // clients from the Unix socket, manging Wayland globals, and so on.
-        server.wl_display = c.wl_display_create() orelse
+        self.wl_display = c.wl_display_create() orelse
             return error.CantCreateWlDisplay;
-        errdefer c.wl_display_destroy(server.wl_display);
+        errdefer c.wl_display_destroy(self.wl_display);
 
         // The wlr_backend abstracts the input/output hardware. Autocreate chooses
         // the best option based on the environment, for example DRM when run from
         // a tty or wayland if WAYLAND_DISPLAY is set.
         //
-        // This frees itserver.when the wl_display is destroyed.
+        // This frees itself.when the wl_display is destroyed.
-        server.wlr_backend = c.zag_wlr_backend_autocreate(server.wl_display) orelse
+        self.wlr_backend = c.zag_wlr_backend_autocreate(self.wl_display) orelse
             return error.CantCreateWlrBackend;
 
         // If we don't provide a renderer, autocreate makes a GLES2 renderer for us.
         // The renderer is responsible for defining the various pixel formats it
         // supports for shared memory, this configures that for clients.
-        server.wlr_renderer = c.zag_wlr_backend_get_renderer(server.wlr_backend) orelse
+        self.wlr_renderer = c.zag_wlr_backend_get_renderer(self.wlr_backend) orelse
             return error.CantGetWlrRenderer;
         // TODO: Handle failure after https://github.com/swaywm/wlroots/pull/2080
-        c.wlr_renderer_init_wl_display(server.wlr_renderer, server.wl_display); // orelse
+        c.wlr_renderer_init_wl_display(self.wlr_renderer, self.wl_display); // orelse
         //    return error.CantInitWlDisplay;
 
         // These both free themselves when the wl_display is destroyed
-        _ = c.wlr_compositor_create(server.wl_display, server.wlr_renderer) orelse
+        _ = c.wlr_compositor_create(self.wl_display, self.wlr_renderer) orelse
             return error.CantCreateWlrCompositor;
-        _ = c.wlr_data_device_manager_create(server.wl_display) orelse
+        _ = c.wlr_data_device_manager_create(self.wl_display) orelse
             return error.CantCreateWlrDataDeviceManager;
 
-        // Create an output layout, which a wlroots utility for working with an
+        self.wlr_xdg_shell = c.wlr_xdg_shell_create(self.wl_display) orelse
-        // arrangement of screens in a physical layout.
-        server.wlr_output_layout = c.wlr_output_layout_create() orelse
-            return error.CantCreateWlrOutputLayout;
-        errdefer c.wlr_output_layout_destroy(server.wlr_output_layout);
-
-        // Don't register the wl_listeners yet as they must first be pointer-stable
-        server.outputs = std.TailQueue(Output).init();
-        server.listen_new_output.notify = handle_new_output;
-
-        server.views = std.TailQueue(View).init();
-        server.wlr_xdg_shell = c.wlr_xdg_shell_create(server.wl_display) orelse
             return error.CantCreateWlrXdgShell;
-        server.listen_new_xdg_surface.notify = handle_new_xdg_surface;
 
-        return server;
+        try self.root.init(self);
-    }
 
-    pub fn init(self: *Self) !void {
         self.seat = try Seat.create(self);
         try self.seat.init();
 
         // Register our listeners for new outputs and xdg_surfaces.
-        // This can't be done in create() as wl_signal_add() creates a pointer
+        self.listen_new_output.notify = handle_new_output;
-        // to the wl_list link in our wl_listener, a pointer that would be
-        // broken when returning from create();
         c.wl_signal_add(&self.wlr_backend.events.new_output, &self.listen_new_output);
+
+        self.listen_new_xdg_surface.notify = handle_new_xdg_surface;
         c.wl_signal_add(&self.wlr_xdg_shell.events.new_surface, &self.listen_new_xdg_surface);
     }
 
     /// Free allocated memory and clean up
-    pub fn destroy(self: Self) void {
+    pub fn destroy(self: *Self) void {
         c.wl_display_destroy_clients(self.wl_display);
         c.wl_display_destroy(self.wl_display);
-        c.wlr_output_layout_destroy(self.wlr_output_layout);
+        self.root.destroy();
     }
 
     /// Create the socket, set WAYLAND_DISPLAY, and start the backend
@@ -148,11 +129,7 @@ pub const Server = struct {
     fn handle_new_output(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
         const server = @fieldParentPtr(Server, "listen_new_output", listener.?);
         const wlr_output = @ptrCast(*c.wlr_output, @alignCast(@alignOf(*c.wlr_output), data));
-
+        server.root.addOutput(wlr_output);
-        // TODO: Handle failure
-        const node = server.outputs.allocateNode(server.allocator) catch unreachable;
-        node.data.init(server, wlr_output) catch unreachable;
-        server.outputs.append(node);
     }
 
     fn handle_new_xdg_surface(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
@@ -162,24 +139,11 @@ pub const Server = struct {
         const wlr_xdg_surface = @ptrCast(*c.wlr_xdg_surface, @alignCast(@alignOf(*c.wlr_xdg_surface), data));
 
         if (wlr_xdg_surface.role != c.enum_wlr_xdg_surface_role.WLR_XDG_SURFACE_ROLE_TOPLEVEL) {
+            // TODO: log
             return;
         }
 
-        // Create a View to handle this toplevel surface
+        // toplevel surfaces are tracked and managed by the root
-        const node = server.views.allocateNode(server.allocator) catch unreachable;
+        server.root.addView(wlr_xdg_surface);
-        node.data.init(server, wlr_xdg_surface);
-        server.views.append(node);
-    }
-
-    /// Finds the top most view under the output layout coordinates lx, ly
-    /// returns the view if found, and a pointer to the wlr_surface as well as the surface coordinates
-    pub fn desktop_view_at(self: *Self, lx: f64, ly: f64, surface: *?*c.wlr_surface, sx: *f64, sy: *f64) ?*View {
-        var it = self.views.last;
-        while (it) |node| : (it = node.prev) {
-            if (node.data.isAt(lx, ly, surface, sx, sy)) {
-                return &node.data;
-            }
-        }
-        return null;
     }
 };

src/view.zig

@@ -1,12 +1,12 @@
 const std = @import("std");
 const c = @import("c.zig").c;
 
-const Server = @import("server.zig").Server;
+const Root = @import("root.zig").Root;
 
 pub const View = struct {
     const Self = @This();
 
-    server: *Server,
+    root: *Root,
     wlr_xdg_surface: *c.wlr_xdg_surface,
 
     mapped: bool,
@@ -19,8 +19,8 @@ pub const View = struct {
     // listen_request_move: c.wl_listener,
     // listen_request_resize: c.wl_listener,
 
-    pub fn init(self: *Self, server: *Server, wlr_xdg_surface: *c.wlr_xdg_surface) void {
+    pub fn init(self: *Self, root: *Root, wlr_xdg_surface: *c.wlr_xdg_surface) void {
-        self.server = server;
+        self.root = root;
         self.wlr_xdg_surface = wlr_xdg_surface;
 
         self.mapped = false;
@@ -55,17 +55,17 @@ pub const View = struct {
 
     fn handleDestroy(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
         const view = @fieldParentPtr(View, "listen_destroy", listener.?);
-        const server = view.server;
+        const root = view.root;
 
-        var it = server.views.first;
+        var it = root.views.first;
         const target = while (it) |node| : (it = node.next) {
             if (&node.data == view) {
                 break node;
             }
         } else unreachable;
 
-        server.views.remove(target);
+        root.views.remove(target);
-        server.views.destroyNode(target, server.allocator);
+        root.views.destroyNode(target, root.server.allocator);
     }
 
     // fn xdgToplevelRequestMove(listener: ?*c.wl_listener, data: ?*c_void) callconv(.C) void {
@@ -77,8 +77,8 @@ pub const View = struct {
     // }
 
     fn focus(self: *Self, surface: *c.wlr_surface) void {
-        const server = self.server;
+        const root = self.root;
-        const wlr_seat = server.seat.wlr_seat;
+        const wlr_seat = root.server.seat.wlr_seat;
         const prev_surface = wlr_seat.keyboard_state.focused_surface;
 
         if (prev_surface == surface) {
@@ -95,7 +95,7 @@ pub const View = struct {
         }
 
         // Find the node
-        var it = server.views.first;
+        var it = root.views.first;
         const target = while (it) |node| : (it = node.next) {
             if (&node.data == self) {
                 break node;
@@ -103,8 +103,8 @@ pub const View = struct {
         } else unreachable;
 
         // Move the view to the front
-        server.views.remove(target);
+        root.views.remove(target);
-        server.views.prepend(target);
+        root.views.prepend(target);
 
         // Activate the new surface
         _ = c.wlr_xdg_toplevel_set_activated(self.wlr_xdg_surface, true);