Merge pull request #1760 from jcollie/notification-suppression

Rate limit desktop notifications

src/App.zig

@@ -45,6 +45,12 @@ quit: bool,
 /// same font configuration.
 font_grid_set: font.SharedGridSet,
 
+// Used to rate limit desktop notifications. Some platforms (notably macOS) will
+// run out of resources if desktop notifications are sent too fast and the OS
+// will kill Ghostty.
+last_notification_time: ?std.time.Instant = null,
+last_notification_digest: u64 = 0,
+
 /// Initialize the main app instance. This creates the main window, sets
 /// up the renderer state, compiles the shaders, etc. This is the primary
 /// "startup" logic.

src/Surface.zig

@@ -3512,9 +3512,47 @@ fn completeClipboardReadOSC52(
 }
 
 fn showDesktopNotification(self: *Surface, title: [:0]const u8, body: [:0]const u8) !void {
-    if (@hasDecl(apprt.Surface, "showDesktopNotification")) {
-        try self.rt_surface.showDesktopNotification(title, body);
-    } else log.warn("runtime doesn't support desktop notifications", .{});
+    if (comptime !@hasDecl(apprt.Surface, "showDesktopNotification")) {
+        log.warn("runtime doesn't support desktop notifications", .{});
+        return;
+    }
+
+    // Wyhash is used to hash the contents of the desktop notification to limit
+    // how fast identical notifications can be sent sequentially.
+    const hash_algorithm = std.hash.Wyhash;
+
+    const now = try std.time.Instant.now();
+
+    // Set a limit of one desktop notification per second so that the OS
+    // doesn't kill us when we run out of resources.
+    if (self.app.last_notification_time) |last| {
+        if (now.since(last) < 1 * std.time.ns_per_s) {
+            log.warn("rate limiting desktop notifications", .{});
+            return;
+        }
+    }
+
+    const new_digest = d: {
+        var hash = hash_algorithm.init(0);
+        hash.update(title);
+        hash.update(body);
+        break :d hash.final();
+    };
+
+    // Set a limit of one notification per five seconds for desktop
+    // notifications with identical content.
+    if (self.app.last_notification_time) |last| {
+        if (self.app.last_notification_digest == new_digest) {
+            if (now.since(last) < 5 * std.time.ns_per_s) {
+                log.warn("suppressing identical desktop notification", .{});
+                return;
+            }
+        }
+    }
+
+    self.app.last_notification_time = now;
+    self.app.last_notification_digest = new_digest;
+    try self.rt_surface.showDesktopNotification(title, body);
 }
 
 pub const face_ttf = @embedFile("font/res/JetBrainsMono-Regular.ttf");