Switch TagOverlay to use river_shell_surface_v1

This follows the same patterns that Wallpaper and Bar did and makes
TagOverlay use the same manage/render cycle as the rest of the WM.

We also switched to just use a poll timer like river-tag-overlay instead
of using the timerfd. I realized that the Zig stdlib doesn't actually
support timerfds for FreeBSD right now and I don't feel like adding them.

docs/CONFIGURATION.md

@@ -195,29 +195,6 @@ tag_overlay {
 | `square_inactive_border_color`      | color | `0x6c7086`   | Inactive tag square border                |
 | `square_inactive_occupied_color`    | color | `0xcdd6f4`   | Inactive tag occupied indicator           |
 
-### Anchors
-
-The `anchors` child block controls which edge(s) of the screen the overlay
-attaches to. Each direction is a boolean (`#true` / `#false`). Default: none, i.e. centered on output.
-
-| Setting  | Type | Default  |
-|----------|------|----------|
-| `top`    | bool | `#false` |
-| `right`  | bool | `#false` |
-| `bottom` | bool | `#false` |
-| `left`   | bool | `#false` |
-
-### Margins
-
-The `margins` child block sets pixel offsets from the anchored edge(s).
-
-| Setting  | Type | Default |
-|----------|------|---------|
-| `top`    | i32  | `0`     |
-| `right`  | i32  | `0`     |
-| `bottom` | i32  | `0`     |
-| `left`   | i32  | `0`     |
-
 ## Keybinds
 
 Keyboard bindings are placed inside a `keybinds` block. Each binding has the

docs/TODO.md

@@ -19,7 +19,6 @@ These are in rough order of my priority, though no promises I do them in this or
 - [ ] Save window positions between restarts
 - [ ] Support multiple seats
 - [ ] Support clipping floating windows on edge of/between outputs
-- [ ] Use per-output timerfds for tag overlay instead of a single shared one
 - [ ] Support configurable focus-follows-window on send-to-output
 - [ ] Support configurable prepend/append on send-to-output
 - [ ] Support taking new output's tags on send-to-output

src/Bar.zig

@@ -119,8 +119,6 @@ pub fn init(context: *Context, output: *Output, options: Options) !Bar {
 }
 
 pub fn deinit(bar: *Bar) void {
-    bar.output.bar = null;
-
     bar.timezone.deinit();
     bar.fcft_fonts.destroy();
 
@@ -128,6 +126,8 @@ pub fn deinit(bar: *Bar) void {
     bar.surfaces.river_shell_surface.destroy();
     bar.surfaces.wl_surface.destroy();
     bar.context.buffer_pool.surface_count -= 1;
+
+    bar.output.bar = null;
 }
 
 /// Update bar options in-place without destroying/recreating Wayland surfaces

src/Buffer.zig

@@ -161,5 +161,10 @@ const seal = switch (builtin.target.os.tag) {
     },
     else => @compileError("target OS not supported"),
 };
+comptime {
+    if (@hasField(os.linux.F, "SEAL_SEAL")) {
+        @compileError("SEAL_SEAL added to std.os.linux, get rid of the hardcoded values above.");
+    }
+}
 
 const log = std.log.scoped(.Buffer);

src/Context.zig

@@ -33,10 +33,6 @@ wallpaper_image: ?*Wallpaper.Image,
 // WM Configuration
 config: *Config,
 
-/// Shared timerfd for hiding tag overlays after their timeout expires.
-/// This stays null if no tag overlays exist.
-tag_overlay_timer_fd: ?posix.fd_t,
-
 /// State consumed in manage() phase, reset at end of manage().
 pending_manage: PendingManage = .{},
 
@@ -73,16 +69,11 @@ pub fn create(options: Options) !*Context {
     const xkb_bindings = try XkbBindings.create(context, options.river_xkb_bindings_v1);
     errdefer xkb_bindings.destroy();
 
-    const env = try process.getEnvMap(utils.gpa);
+    var env = try process.getEnvMap(utils.gpa);
     errdefer env.deinit();
 
-    const tag_overlay_timer_fd: ?posix.fd_t = if (options.config.tag_overlay_config) |_|
+    // Don't force children to have WAYLAND_DEBUG
-        posix.timerfd_create(.MONOTONIC, .{ .CLOEXEC = true }) catch |e| blk: {
+    env.remove("WAYLAND_DEBUG");
-            log.err("Failed to create tag overlay timer: {}", .{e});
-            break :blk null;
-        }
-    else
-        null;
 
     context.* = .{
         .initialized = false,
@@ -98,7 +89,6 @@ pub fn create(options: Options) !*Context {
         .wm = wm,
         .xkb_bindings = xkb_bindings,
         .config = options.config,
-        .tag_overlay_timer_fd = tag_overlay_timer_fd,
     };
 
     return context;
@@ -113,7 +103,6 @@ pub fn destroy(context: *Context) void {
     if (context.wallpaper_image) |wallpaper_image| {
         wallpaper_image.destroy();
     }
-    if (context.tag_overlay_timer_fd) |fd| posix.close(fd);
     context.buffer_pool.deinit();
 
     // Destroy Wayland globals
@@ -168,30 +157,21 @@ pub fn manage(context: *Context) void {
         // Handle tag overlay config changes
         const has_overlay = new_config.tag_overlay_config != null;
 
-        if (!had_overlay and has_overlay) {
+        // Reconfigure, create, or destroy tag overlays on all outputs
-            // Create timerfd for newly enabled tag overlay
-            context.tag_overlay_timer_fd = posix.timerfd_create(.MONOTONIC, .{ .CLOEXEC = true }) catch |e| blk: {
-                log.err("Failed to create tag overlay timer: {}", .{e});
-                break :blk null;
-            };
-        } else if (had_overlay and !has_overlay) {
-            // Close timerfd for disabled tag overlay
-            if (context.tag_overlay_timer_fd) |fd| posix.close(fd);
-            context.tag_overlay_timer_fd = null;
-        }
-
-        // Recreate or destroy tag overlays on all outputs
         if (had_overlay or has_overlay) {
             var out_it = context.wm.outputs.iterator(.forward);
             while (out_it.next()) |output| {
-                // Destroy existing overlay
                 if (output.tag_overlay) |*tag_overlay| {
-                    tag_overlay.deinit();
-                    output.tag_overlay = null;
-                }
-                // Create new overlay if configured
-                // Create new overlay struct if configured (surfaces created on-demand)
                     if (new_config.tag_overlay_config) |tag_overlay_config| {
+                        // Reconfigure existing overlay
+                        tag_overlay.deinitSurfaces();
+                        tag_overlay.reconfigure(tag_overlay_config.toTagOverlayOptions());
+                    } else {
+                        // Remove overlay
+                        tag_overlay.deinit();
+                    }
+                } else if (new_config.tag_overlay_config) |tag_overlay_config| {
+                    // Create new overlay struct (surfaces created on-demand)
                     output.tag_overlay = TagOverlay.init(context, output, tag_overlay_config.toTagOverlayOptions()) catch |e| {
                         log.err("Failed to create tag overlay: {}", .{e});
                         continue;

src/Output.zig

@@ -102,7 +102,6 @@ pub fn create(context: *Context, river_output_v1: *river.OutputV1) !*Output {
             break :blk null;
         };
     } else null;
-    errdefer if (output.tag_overlay) |*to| to.deinit();
 
     output.windows.init();
 
@@ -388,31 +387,15 @@ pub fn manage(output: *Output) void {
             }
         }
 
-        // Show tag overlay and arm the hide timer
+        // Show tag overlay (or refresh its timeout if already visible)
-        if (output.tag_overlay) |*tag_overlay| {
+        if (output.tag_overlay) |*tag_overlay| blk: {
-            if (tag_overlay.surfaces) |_| {
+            tag_overlay.initSurfaces() catch |e| {
-                // The overlay is already visible, but we still need to re-render
+                log.err("Failed to show TagOverlay: {}", .{e});
-                tag_overlay.render() catch |err| {
+                break :blk;
-                    log.err("tag_overlay render failed: {}", .{err});
             };
-            } else {
+            tag_overlay.last_shown = time.Instant.now() catch
-                // Create surface; the configure handler renders for us
+                std.process.fatal("System does not support a monotonic or steady clock", .{});
-                tag_overlay.initSurface() catch |err| {
+            tag_overlay.pending_render.draw = true;
-                    log.err("tag_overlay initSurface failed: {}", .{err});
-                };
-            }
-            if (output.context.tag_overlay_timer_fd) |fd| {
-                const timeout_ms: isize = tag_overlay.options.timeout;
-                posix.timerfd_settime(fd, .{}, &.{
-                    .it_interval = .{ .sec = 0, .nsec = 0 },
-                    .it_value = .{
-                        .sec = @divFloor(timeout_ms, 1000),
-                        .nsec = @mod(timeout_ms, 1000) * std.time.ns_per_ms,
-                    },
-                }, null) catch |err| {
-                    log.err("Failed to arm tag overlay timer: {}", .{err});
-                };
-            }
         }
 
         if (output.bar) |*bar| {
@@ -487,6 +470,10 @@ pub fn render(output: *Output) void {
             f.river_node_v1.placeTop();
         }
     }
+
+    if (output.tag_overlay) |*tag_overlay| {
+        tag_overlay.render();
+    }
 }
 
 /// Calculate primary/stack layout positions for all windows.
@@ -649,6 +636,7 @@ const std = @import("std");
 const assert = std.debug.assert;
 const mem = std.mem;
 const posix = std.posix;
+const time = std.time;
 const DoublyLinkedList = std.DoublyLinkedList;
 
 const wayland = @import("wayland");

src/TagOverlay.zig

@@ -13,19 +13,23 @@ options: Options,
 
 output: *Output,
 
-// Overlay geometry
-width: u31 = 0,
-height: u31 = 0,
-scale: u31 = 1,
-
 rows: u31,
 
 surfaces: ?struct {
     wl_surface: *wl.Surface,
-    layer_surface: *zwlr.LayerSurfaceV1,
+    river_shell_surface: *river.ShellSurfaceV1,
+    node: *river.NodeV1,
 } = null,
 
-configured: bool = false,
+/// Monotonic timestamp of the last time the overlay was shown/refreshed.
+/// Used by the event loop to hide the overlay after `options.timeout` ms.
+last_shown: ?time.Instant = null,
+
+pending_render: PendingRender = .{},
+
+pub const PendingRender = struct {
+    draw: bool = false,
+};
 
 pub const Options = struct {
     /// Width of the widget border in pixels
@@ -65,10 +69,6 @@ pub const Options = struct {
     // square_urgent_border_color: pixman.Color,
     // /// Occupied indicator color of urgent tag squares
     // square_urgent_occupied_color: pixman.Color,
-    /// Directional anchors top, right bottom, left; true for on, false for off
-    anchors: zwlr.LayerSurfaceV1.Anchor,
-    /// Directional margins top, right, bottom, left, in pixels
-    margins: struct { top: i32 = 0, right: i32 = 0, bottom: i32 = 0, left: i32 = 0 } = .{},
     /// Duration of widget display in milliseconds
     timeout: u32,
 };
@@ -84,113 +84,86 @@ pub fn init(context: *Context, output: *Output, options: Options) !TagOverlay {
     };
 }
 
-pub fn initSurface(tag_overlay: *TagOverlay) !void {
+pub fn deinit(tag_overlay: *TagOverlay) void {
-    if (tag_overlay.surfaces) |_| {
+    tag_overlay.deinitSurfaces();
-        // This tag overlay already has a layer surface, we can exit early
+    tag_overlay.output.tag_overlay = null;
+}
+
+pub fn reconfigure(tag_overlay: *TagOverlay, options: Options) void {
+    tag_overlay.options = options;
+    tag_overlay.rows = math.divCeil(u31, options.tag_amount, options.tags_per_row) catch {
+        log.err("Failed to calculate rows for tag overlay", .{});
         return;
-    }
+    };
+}
+
+pub fn initSurfaces(tag_overlay: *TagOverlay) !void {
+    if (tag_overlay.surfaces != null) return;
 
     const context = tag_overlay.context;
-    const options = tag_overlay.options;
 
     const wl_surface = try context.wl_compositor.createSurface();
     errdefer wl_surface.destroy();
 
-    const layer_surface = try context
+    const river_shell_surface = try context
-        .zwlr_layer_shell_v1
+        .wm
-        .getLayerSurface(wl_surface, tag_overlay.output.wl_output, .overlay, "beansprout-tag-overlay");
+        .river_window_manager_v1
-    errdefer layer_surface.destroy();
+        .getShellSurface(wl_surface);
-    layer_surface.setExclusiveZone(-1);
+    errdefer river_shell_surface.destroy();
+
+    const node = try river_shell_surface.getNode();
+    errdefer node.destroy();
 
     // We don't want our surface to have any input region (default is infinite)
     const empty_region = try context.wl_compositor.createRegion();
     defer empty_region.destroy();
     wl_surface.setInputRegion(empty_region);
 
-    const surface_width: u31 = @as(u31, @min(options.tag_amount, options.tags_per_row)) * (@as(u31, options.square_size) + options.square_padding) + options.square_padding + 2 * @as(u31, options.border_width);
+    const now = time.Instant.now() catch
-    const surface_height: u31 = @as(u31, tag_overlay.rows) * (@as(u31, options.square_size) + options.square_padding) + options.square_padding + 2 * @as(u31, options.border_width);
+        std.process.fatal("System does not support a monotonic or steady clock", .{});
-    layer_surface.setSize(surface_width, surface_height);
 
-    layer_surface.setAnchor(options.anchors);
-    layer_surface.setMargin(options.margins.top, options.margins.right, options.margins.bottom, options.margins.left);
-
-    tag_overlay.surfaces = .{ .wl_surface = wl_surface, .layer_surface = layer_surface };
     context.buffer_pool.surface_count += 1;
 
-    layer_surface.setListener(*TagOverlay, layerSurfaceListener, tag_overlay);
+    tag_overlay.surfaces = .{
-    wl_surface.commit();
+        .wl_surface = wl_surface,
+        .river_shell_surface = river_shell_surface,
+        .node = node,
+    };
+    tag_overlay.last_shown = now;
+    tag_overlay.pending_render.draw = true;
 }
 
-/// Destroy surfaces only (used to hide the overlay). The TagOverlay struct stays valid
-/// and can be re-shown by calling initSurface() again.
 pub fn deinitSurfaces(tag_overlay: *TagOverlay) void {
-    tag_overlay.configured = false;
+    const surfaces = tag_overlay.surfaces orelse return;
-    if (tag_overlay.surfaces) |surfaces| {
+    surfaces.node.destroy();
-        surfaces.layer_surface.destroy();
+    surfaces.river_shell_surface.destroy();
     surfaces.wl_surface.destroy();
     tag_overlay.context.buffer_pool.surface_count -= 1;
     tag_overlay.surfaces = null;
-    }
+    tag_overlay.last_shown = null;
 }
 
-pub fn deinit(tag_overlay: *TagOverlay) void {
+pub fn render(tag_overlay: *TagOverlay) void {
-    tag_overlay.deinitSurfaces();
+    defer tag_overlay.pending_render = .{};
-}
 
-pub fn layerSurfaceListener(
+    if (tag_overlay.pending_render.draw) {
-    layer_surface: *zwlr.LayerSurfaceV1,
+        tag_overlay.draw() catch |err| {
-    event: zwlr.LayerSurfaceV1.Event,
+            log.err("tag_overlay draw failed: {}", .{err});
-    tag_overlay: *TagOverlay,
-) void {
-    assert(tag_overlay.surfaces.?.layer_surface == layer_surface);
-    switch (event) {
-        .configure => |ev| {
-            layer_surface.ackConfigure(ev.serial);
-            const width: u31 = @intCast(ev.width);
-            const height: u31 = @intCast(ev.height);
-
-            if (tag_overlay.configured and
-                tag_overlay.width == width and
-                tag_overlay.height == height and
-                tag_overlay.output.scale == tag_overlay.scale)
-            {
-                tag_overlay.surfaces.?.wl_surface.commit();
-                return;
-            }
-
-            log.debug("Configuring tag_overlay surface with width {} and height {}", .{ width, height });
-            tag_overlay.width = width;
-            tag_overlay.height = height;
-
-            // Full surface should be opaque
-            const opaque_region: *wl.Region = tag_overlay.context.wl_compositor.createRegion() catch |e| {
-                log.err("Failed to create opaque region for tag_overlay: {}", .{e});
-                return;
         };
-            defer opaque_region.destroy();
-            opaque_region.add(0, 0, tag_overlay.width, tag_overlay.height);
-            tag_overlay.surfaces.?.wl_surface.setOpaqueRegion(opaque_region);
-
-            tag_overlay.configured = true;
-
-            tag_overlay.render() catch |err| {
-                log.err("tag_overlay render failed: {}", .{err});
-            };
-        },
-        .closed => {
-            tag_overlay.deinit();
-        },
     }
 }
 
-pub fn render(tag_overlay: *TagOverlay) !void {
+pub fn draw(tag_overlay: *TagOverlay) !void {
+    const surfaces = tag_overlay.surfaces orelse return;
     const context = tag_overlay.context;
     const options = tag_overlay.options;
 
     // Scaled width/height
+    const surface_width: u31 = @as(u31, @min(options.tag_amount, options.tags_per_row)) * (@as(u31, options.square_size) + options.square_padding) + options.square_padding + 2 * @as(u31, options.border_width);
+    const surface_height: u31 = @as(u31, tag_overlay.rows) * (@as(u31, options.square_size) + options.square_padding) + options.square_padding + 2 * @as(u31, options.border_width);
     const scale = tag_overlay.output.scale;
-    const render_width = tag_overlay.width * scale;
+    const render_width = surface_width * scale;
-    const render_height = tag_overlay.height * scale;
+    const render_height = surface_height * scale;
 
     // Don't have anything to render
     if (render_width == 0 or render_height == 0) {
@@ -198,7 +171,7 @@ pub fn render(tag_overlay: *TagOverlay) !void {
     }
     const buffer = try context.buffer_pool.nextBuffer(context.wl_shm, render_width, render_height);
 
-    buffer.borderedRectangle(.{ .width = tag_overlay.width, .height = tag_overlay.height }, options.border_width, scale, &options.background_color, &options.border_color);
+    buffer.borderedRectangle(.{ .width = surface_width, .height = surface_height }, options.border_width, scale, &options.background_color, &options.border_color);
 
     const focused_tags = tag_overlay.output.tags;
     const occupied_tags = tag_overlay.output.occupiedTags();
@@ -237,8 +210,14 @@ pub fn render(tag_overlay: *TagOverlay) !void {
         }
     }
 
+    // Position the overlay centered on the output
+    const output_geo = tag_overlay.output.geometry;
+    const x = output_geo.x + @divFloor(output_geo.width - surface_width, 2);
+    const y = output_geo.y + @divFloor(output_geo.height - surface_height, 2);
+    surfaces.node.setPosition(x, y);
+    surfaces.node.placeTop();
+
     // Finally, attach the buffer to the surface
-    const surfaces = tag_overlay.surfaces orelse return error.NoSurfaces;
     const wl_surface = surfaces.wl_surface;
     wl_surface.setBufferScale(scale);
     wl_surface.attach(buffer.wl_buffer, 0, 0);
@@ -249,10 +228,11 @@ pub fn render(tag_overlay: *TagOverlay) !void {
 const std = @import("std");
 const assert = std.debug.assert;
 const math = std.math;
+const time = std.time;
 
 const wayland = @import("wayland");
 const wl = wayland.client.wl;
-const zwlr = wayland.client.zwlr;
+const river = wayland.client.river;
 const fcft = @import("fcft");
 const pixman = @import("pixman");
 

src/Wallpaper.zig

@@ -137,12 +137,13 @@ pub fn init(context: *Context, output: *Output) !Wallpaper {
 }
 
 pub fn deinit(wallpaper: *Wallpaper) void {
-    wallpaper.output.wallpaper = null;
-
     wallpaper.surfaces.node.destroy();
     wallpaper.surfaces.river_shell_surface.destroy();
     wallpaper.surfaces.wl_surface.destroy();
+
     wallpaper.context.buffer_pool.surface_count -= 1;
+
+    wallpaper.output.wallpaper = null;
 }
 
 pub fn render(wallpaper: *Wallpaper) void {

src/XkbBindings.zig

@@ -140,6 +140,7 @@ const XkbBinding = struct {
         switch (xkb_binding.command) {
             .spawn => |cmd| {
                 var child = std.process.Child.init(cmd, utils.gpa);
+                child.env_map = &context.env;
                 _ = child.spawn() catch |err| {
                     log.err("Failed to spawn \"{s}\": {}", .{ cmd[0], err });
                 };

src/config/InputConfig.zig

@@ -126,9 +126,7 @@ pub fn load(config: *Config, parser: *kdl.Parser, name: ?[]const u8, hostname: ?
                     helpers.logWarnInvalidNode(node.name);
                 }
             },
-            .child_block_begin => {
+            .child_block_begin => try helpers.skipChildBlock(parser),
-                try helpers.skipChildBlock(parser);
-            },
             .child_block_end => {
                 try config.input_configs.append(utils.gpa, input_config);
                 return;

src/config/TagOverlayConfig.zig

@@ -21,13 +21,8 @@ const NodeName = enum {
     square_inactive_border_color,
     square_inactive_occupied_color,
     timeout,
-    anchors,
-    margins,
 };
 
-const AnchorsNodeName = enum { top, right, bottom, left };
-const MarginsNodeName = enum { top, right, bottom, left };
-
 border_width: u8 = 2,
 tag_amount: u8 = 9,
 tags_per_row: u8 = 32,
@@ -44,14 +39,6 @@ square_inactive_background_color: pixman.Color = utils.parseRgbaPixmanComptime("
 square_inactive_border_color: pixman.Color = utils.parseRgbaPixmanComptime("0x6c7086"),
 square_inactive_occupied_color: pixman.Color = utils.parseRgbaPixmanComptime("0xcdd6f4"),
 timeout: u32 = 500,
-anchor_top: bool = false,
-anchor_right: bool = false,
-anchor_bottom: bool = false,
-anchor_left: bool = false,
-margin_top: i32 = 0,
-margin_right: i32 = 0,
-margin_bottom: i32 = 0,
-margin_left: i32 = 0,
 
 pub fn toTagOverlayOptions(config: TagOverlayConfig) TagOverlay.Options {
     return .{
@@ -70,18 +57,6 @@ pub fn toTagOverlayOptions(config: TagOverlayConfig) TagOverlay.Options {
         .square_inactive_background_color = config.square_inactive_background_color,
         .square_inactive_border_color = config.square_inactive_border_color,
         .square_inactive_occupied_color = config.square_inactive_occupied_color,
-        .anchors = .{
-            .top = config.anchor_top,
-            .right = config.anchor_right,
-            .bottom = config.anchor_bottom,
-            .left = config.anchor_left,
-        },
-        .margins = .{
-            .top = config.margin_top,
-            .right = config.margin_right,
-            .bottom = config.margin_bottom,
-            .left = config.margin_left,
-        },
         .timeout = config.timeout,
     };
 }
@@ -89,16 +64,9 @@ pub fn toTagOverlayOptions(config: TagOverlayConfig) TagOverlay.Options {
 pub fn load(config: *Config, parser: *kdl.Parser, hostname: ?[]const u8) !void {
     config.tag_overlay_config = .{}; // Presence of block = enabled; initialize with defaults
 
-    const TagOverlayChild = enum { anchors, margins };
-    var next_child_block: ?TagOverlayChild = null;
-
     while (try parser.next()) |event| {
         switch (event) {
             .node => |node| {
-                if (next_child_block) |child| {
-                    log.warn("Expected child block for tag_overlay.{s}, got node instead. Ignoring", .{@tagName(child)});
-                    next_child_block = null;
-                }
                 const node_name = std.meta.stringToEnum(NodeName, node.name);
                 if (node_name) |name| {
                     if (!helpers.hostMatches(node, parser, hostname)) {
@@ -107,8 +75,6 @@ pub fn load(config: *Config, parser: *kdl.Parser, hostname: ?[]const u8) !void {
                     }
                     const val_str = utils.stripQuotes(node.arg(parser, 0) orelse "");
                     switch (name) {
-                        .anchors => next_child_block = .anchors,
-                        .margins => next_child_block = .margins,
                         // These are all u8s, so we can inline the branch
                         inline .border_width,
                         .tag_amount,
@@ -152,80 +118,6 @@ pub fn load(config: *Config, parser: *kdl.Parser, hostname: ?[]const u8) !void {
                     helpers.logWarnInvalidNode(node.name);
                 }
             },
-            .child_block_begin => {
-                if (next_child_block) |child| {
-                    switch (child) {
-                        .anchors => try loadAnchorsBlock(config, parser, hostname),
-                        .margins => try loadMarginsBlock(config, parser, hostname),
-                    }
-                    next_child_block = null;
-                } else {
-                    try helpers.skipChildBlock(parser);
-                }
-            },
-            .child_block_end => return,
-        }
-    }
-}
-
-fn loadAnchorsBlock(config: *Config, parser: *kdl.Parser, hostname: ?[]const u8) !void {
-    while (try parser.next()) |event| {
-        switch (event) {
-            .node => |node| {
-                const node_name = std.meta.stringToEnum(AnchorsNodeName, node.name);
-                if (node_name) |name| {
-                    if (!helpers.hostMatches(node, parser, hostname)) {
-                        logDebugHostMismatch(name);
-                        continue;
-                    }
-                    const val_str = utils.stripQuotes(node.arg(parser, 0) orelse "");
-                    if (helpers.boolFromKdlStr(val_str)) |val| {
-                        switch (name) {
-                            .top => config.tag_overlay_config.?.anchor_top = val,
-                            .right => config.tag_overlay_config.?.anchor_right = val,
-                            .bottom => config.tag_overlay_config.?.anchor_bottom = val,
-                            .left => config.tag_overlay_config.?.anchor_left = val,
-                        }
-                        logDebugSettingNode(name, val_str);
-                    } else |_| {
-                        logWarnInvalidNodeArg(name, val_str);
-                    }
-                } else {
-                    helpers.logWarnInvalidNode(node.name);
-                }
-            },
-            .child_block_begin => try helpers.skipChildBlock(parser),
-            .child_block_end => return,
-        }
-    }
-}
-
-fn loadMarginsBlock(config: *Config, parser: *kdl.Parser, hostname: ?[]const u8) !void {
-    while (try parser.next()) |event| {
-        switch (event) {
-            .node => |node| {
-                const node_name = std.meta.stringToEnum(MarginsNodeName, node.name);
-                if (node_name) |name| {
-                    if (!helpers.hostMatches(node, parser, hostname)) {
-                        logDebugHostMismatch(name);
-                        continue;
-                    }
-                    const val_str = utils.stripQuotes(node.arg(parser, 0) orelse "");
-                    const val = fmt.parseInt(i32, val_str, 10) catch {
-                        logWarnInvalidNodeArg(name, val_str);
-                        continue;
-                    };
-                    switch (name) {
-                        .top => config.tag_overlay_config.?.margin_top = val,
-                        .right => config.tag_overlay_config.?.margin_right = val,
-                        .bottom => config.tag_overlay_config.?.margin_bottom = val,
-                        .left => config.tag_overlay_config.?.margin_left = val,
-                    }
-                    logDebugSettingNode(name, val_str);
-                } else {
-                    helpers.logWarnInvalidNode(node.name);
-                }
-            },
             .child_block_begin => try helpers.skipChildBlock(parser),
             .child_block_end => return,
         }
@@ -236,8 +128,6 @@ inline fn logDebugSettingNode(node_name: anytype, node_value: []const u8) void {
     const node_name_type = @TypeOf(node_name);
     switch (node_name_type) {
         NodeName => log.debug("Setting tag_overlay.{s} to {s}", .{ @tagName(node_name), node_value }),
-        AnchorsNodeName => log.debug("Setting tag_overlay.anchors.{s} to {s}", .{ @tagName(node_name), node_value }),
-        MarginsNodeName => log.debug("Setting tag_overlay.margins.{s} to {s}", .{ @tagName(node_name), node_value }),
         else => @compileError("This function does not (yet) support type \"" ++ @typeName(@TypeOf(node_name)) ++ "\""),
     }
 }
@@ -246,8 +136,6 @@ inline fn logDebugHostMismatch(node_name: anytype) void {
     const node_name_type = @TypeOf(node_name);
     switch (node_name_type) {
         NodeName => log.debug("Skipping \"tag_overlay.{s}\" (host mismatch)", .{@tagName(node_name)}),
-        AnchorsNodeName => log.debug("Skipping \"tag_overlay.anchors.{s}\" (host mismatch)", .{@tagName(node_name)}),
-        MarginsNodeName => log.debug("Skipping \"tag_overlay.margins.{s}\" (host mismatch)", .{@tagName(node_name)}),
         else => @compileError("This function does not (yet) support type \"" ++ @typeName(node_name_type) ++ "\""),
     }
 }
@@ -256,8 +144,6 @@ inline fn logWarnInvalidNodeArg(node_name: anytype, node_value: []const u8) void
     const node_name_type = @TypeOf(node_name);
     switch (node_name_type) {
         NodeName => log.warn("Invalid \"tag_overlay.{s}\" ({s}). Using default value", .{ @tagName(node_name), node_value }),
-        AnchorsNodeName => log.warn("Invalid \"tag_overlay.anchors.{s}\" ({s}). Using default value", .{ @tagName(node_name), node_value }),
-        MarginsNodeName => log.warn("Invalid \"tag_overlay.margins.{s}\" ({s}). Using default value", .{ @tagName(node_name), node_value }),
         else => @compileError("This function does not (yet) support type \"" ++ @typeName(node_name_type) ++ "\""),
     }
 }

src/main.zig

@@ -12,7 +12,6 @@ const Globals = struct {
 
     wl_compositor: ?*wl.Compositor = null,
     wl_shm: ?*wl.Shm = null,
-
     zwlr_layer_shell_v1: ?*zwlr.LayerShellV1 = null,
 };
 
@@ -102,9 +101,8 @@ fn run(wl_display: *wl.Display, context: *Context) !void {
 
     const poll_wayland = 0;
     const poll_sig = 1;
-    const poll_tag_overlay_timer = 2;
 
-    var pollfds: [3]posix.pollfd = undefined;
+    var pollfds: [2]posix.pollfd = undefined;
 
     pollfds[poll_wayland] = .{
         .fd = wl_display.getFd(),
@@ -116,12 +114,6 @@ fn run(wl_display: *wl.Display, context: *Context) !void {
         .events = posix.POLL.IN,
         .revents = 0,
     };
-    pollfds[poll_tag_overlay_timer] = .{
-        // poll ignores negative fds
-        .fd = context.tag_overlay_timer_fd orelse -1,
-        .events = posix.POLL.IN,
-        .revents = 0,
-    };
 
     while (true) {
         const flush_errno = wl_display.flush();
@@ -136,18 +128,38 @@ fn run(wl_display: *wl.Display, context: *Context) !void {
             pollfds[poll_wayland].events = posix.POLL.IN;
         }
 
-        // Get the number of milliseconds to the top of the next second
+        // Compute poll timeout: minimum of clock update and tag overlay expiry
-        const time_ns = std.time.nanoTimestamp();
+        var timeout: i32 = blk: {
-        const ns_per_sec = std.time.ns_per_s;
+            // Milliseconds until the top of the next second (for clock updates)
-        const remainder_ns = @mod(time_ns, ns_per_sec);
+            const time_ns = time.nanoTimestamp();
-        const timeout: i32 = @intCast(@divFloor(ns_per_sec - remainder_ns, std.time.ns_per_ms));
+            const remainder_ns = @mod(time_ns, time.ns_per_s);
+            break :blk @intCast(@divFloor(time.ns_per_s - remainder_ns, time.ns_per_ms));
+        };
+
+        // Check for expired tag overlays and find the soonest expiry
+        const now = time.Instant.now() catch
+            fatal("System does not support a monotonic or steady clock", .{});
+        {
+            var it = context.wm.outputs.iterator(.forward);
+            while (it.next()) |output| {
+                const tag_overlay = output.tag_overlay orelse continue;
+                const last_shown = tag_overlay.last_shown orelse continue;
+                const elapsed_ns = now.since(last_shown);
+                const timeout_ns: u64 = @as(u64, tag_overlay.options.timeout) * time.ns_per_ms;
+                if (elapsed_ns >= timeout_ns) {
+                    output.tag_overlay.?.deinitSurfaces();
+                } else {
+                    const remaining_ms: i32 = @intCast((timeout_ns - elapsed_ns) / time.ns_per_ms);
+                    timeout = @min(timeout, remaining_ms);
+                }
+            }
+        }
 
         const poll_rc = posix.poll(&pollfds, timeout) catch |err| {
             fatal("Failed to poll {s}", .{@errorName(err)});
         };
         if (poll_rc == 0) {
-            // If poll returns 0, it timed out, meaning we hit the top of the next second
+            // Update the clock
-            // and need to update the clock.
             var it = context.wm.outputs.iterator(.forward);
             while (it.next()) |output| {
                 if (output.bar) |*bar| {
@@ -168,8 +180,6 @@ fn run(wl_display: *wl.Display, context: *Context) !void {
                 @branchHint(.cold);
                 fatal("Wayland display dispatch failed", .{});
             }
-            // Re-sync in case a config reload created or destroyed the timerfd
-            pollfds[poll_tag_overlay_timer].fd = context.tag_overlay_timer_fd orelse -1;
         }
 
         if (pollfds[poll_sig].revents & posix.POLL.HUP != 0) {
@@ -181,24 +191,6 @@ fn run(wl_display: *wl.Display, context: *Context) !void {
             log.info("Exiting beansprout", .{});
             break;
         }
-
-        if (pollfds[poll_tag_overlay_timer].revents & posix.POLL.HUP != 0) {
-            @branchHint(.cold);
-            fatal("Tag overlay timer fd hung up", .{});
-        }
-        if (pollfds[poll_tag_overlay_timer].revents & posix.POLL.IN != 0) {
-            // Read to consume the timer event
-            var buf: [8]u8 = undefined;
-            _ = posix.read(context.tag_overlay_timer_fd.?, &buf) catch {};
-
-            // Hide all tag overlays by destroying their surfaces
-            var it = context.wm.outputs.iterator(.forward);
-            while (it.next()) |output| {
-                if (output.tag_overlay) |*tag_overlay| {
-                    tag_overlay.deinitSurfaces();
-                }
-            }
-        }
     }
 }
 
@@ -338,6 +330,7 @@ const mem = std.mem;
 const os = std.os;
 const posix = std.posix;
 const process = std.process;
+const time = std.time;
 
 const wayland = @import("wayland");
 const river = wayland.client.river;