linux: add dbus and systemd activation services

dist/linux/app.desktop

@@ -1,8 +1,10 @@
 [Desktop Entry]
+Version=1.0
 Name=Ghostty
 Type=Application
 Comment=A terminal emulator
-Exec=ghostty
+TryExec=ghostty
+Exec=ghostty %F
 Icon=com.mitchellh.ghostty
 Categories=System;TerminalEmulator;
 Keywords=terminal;tty;pty;
@@ -16,6 +18,7 @@ X-TerminalArgTitle=--title=
 X-TerminalArgAppId=--class=
 X-TerminalArgDir=--working-directory=
 X-TerminalArgHold=--wait-after-command
+DBusActivatable=true
 
 [Desktop Action new-window]
 Name=New Window

dist/linux/dbus.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=com.mitchellh.ghostty
+SystemdService=com.mitchellh.ghostty.service
+Exec=ghostty

dist/linux/systemd.service

@@ -0,0 +1,7 @@
+[Unit]
+Description=Ghostty
+
+[Service]
+Type=dbus
+BusName=com.mitchellh.ghostty
+ExecStart=ghostty

nix/package.nix

@@ -117,6 +117,11 @@ in
 
       mkdir -p "$out/nix-support"
 
+      sed -i -e "s@^Exec=.*ghostty@Exec=$out/bin/ghostty@" $out/share/applications/com.mitchellh.ghostty.desktop
+      sed -i -e "s@^TryExec=.*ghostty@TryExec=$out/bin/ghostty@" $out/share/applications/com.mitchellh.ghostty.desktop
+      sed -i -e "s@^Exec=.*ghostty@Exec=$out/bin/ghostty@" $out/share/dbus-1/services/com.mitchellh.ghostty.service
+      sed -i -e "s@^ExecStart=.*ghostty@ExecStart=$out/bin/ghostty@" $out/lib/systemd/user/com.mitchellh.ghostty.service
+
       mkdir -p "$terminfo/share"
       mv "$terminfo_src" "$terminfo/share/terminfo"
       ln -sf "$terminfo/share/terminfo" "$terminfo_src"

src/apprt/gtk/App.zig

@@ -400,11 +400,15 @@ pub fn init(core_app: *CoreApp, opts: Options) !App {
     // This just calls the `activate` signal but its part of the normal startup
     // routine so we just call it, but only if the config allows it (this allows
     // for launching Ghostty in the "background" without immediately opening
-    // a window)
+    // a window). An initial window will not be immediately created if we were
+    // launched by D-Bus activation or systemd.  D-Bus activation will send it's
+    // own `activate` or `new-window` signal later.
     //
     // https://gitlab.gnome.org/GNOME/glib/-/blob/bd2ccc2f69ecfd78ca3f34ab59e42e2b462bad65/gio/gapplication.c#L2302
-    if (config.@"initial-window")
-        gio_app.activate();
+    if (config.@"initial-window") switch (config.@"launched-from".?) {
+        .dbus, .systemd => {},
+        else => gio_app.activate(),
+    };
 
     // Internally, GTK ensures that only one instance of this provider exists in the provider list
     // for the display.
@@ -1678,6 +1682,17 @@ fn gtkActionShowGTKInspector(
     };
 }
 
+fn gtkActionNewWindow(
+    _: *gio.SimpleAction,
+    _: ?*glib.Variant,
+    self: *App,
+) callconv(.c) void {
+    log.info("received new window action", .{});
+    _ = self.core_app.mailbox.push(.{
+        .new_window = .{},
+    }, .{ .forever = {} });
+}
+
 /// This is called to setup the action map that this application supports.
 /// This should be called only once on startup.
 fn initActions(self: *App) void {
@@ -1697,7 +1712,9 @@ fn initActions(self: *App) void {
         .{ "reload-config", gtkActionReloadConfig, null },
         .{ "present-surface", gtkActionPresentSurface, t },
         .{ "show-gtk-inspector", gtkActionShowGTKInspector, null },
+        .{ "new-window", gtkActionNewWindow, null },
     };
+
     inline for (actions) |entry| {
         const action = gio.SimpleAction.new(entry[0], entry[2]);
         defer action.unref();

src/apprt/gtk/Surface.zig

@@ -2325,6 +2325,15 @@ pub fn defaultTermioEnv(self: *Surface) !std.process.EnvMap {
     env.remove("GDK_DISABLE");
     env.remove("GSK_RENDERER");
 
+    // Remove some environment variables that are set when Ghostty is launched
+    // from a `.desktop` file, by D-Bus activation, or systemd.
+    env.remove("GIO_LAUNCHED_DESKTOP_FILE");
+    env.remove("GIO_LAUNCHED_DESKTOP_FILE_PID");
+    env.remove("DBUS_STARTER_ADDRESS");
+    env.remove("DBUS_STARTER_BUS_TYPE");
+    env.remove("INVOCATION_ID");
+    env.remove("JOURNAL_STREAM");
+
     // Unset environment varies set by snaps if we're running in a snap.
     // This allows Ghostty to further launch additional snaps.
     if (env.get("SNAP")) |_| {

src/build/GhosttyResources.zig

@@ -201,6 +201,16 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyResources {
             b.path("dist/linux/app.desktop"),
             "share/applications/com.mitchellh.ghostty.desktop",
         ).step);
+        // DBus service for DBus activation
+        try steps.append(&b.addInstallFile(
+            b.path("dist/linux/dbus.service"),
+            "share/dbus-1/services/com.mitchellh.ghostty.service",
+        ).step);
+        // systemd user service
+        try steps.append(&b.addInstallFile(
+            b.path("dist/linux/systemd.service"),
+            "lib/systemd/user/com.mitchellh.ghostty.service",
+        ).step);
 
         // AppStream metainfo so that application has rich metadata within app stores
         try steps.append(&b.addInstallFile(