client: Add request::activate signal (FS#848)

When we receive a _NET_ACTIVE_WINDOW request on the root window, we used to just
focus and raise the window. This didn't do much for clients which are on
non-selected tags.

Thus, this commit makes awesome emit request::activate on the client instead.
This is used in awful.ewmh to implement the old behavior again, but with
additionally marking the client as urgent if it isn't visible.

People who don't like this behavior can use client.disconnect_signal to disable
this behavior again. To make this really possible, awful.ewmh becomes a
"non-nil" module.

Signed-off-by: Uli Schlachter <psychon@znc.in>

ewmh.c

@@ -401,8 +401,9 @@ ewmh_process_client_message(xcb_client_message_event_t *ev)
     else if(ev->type == _NET_ACTIVE_WINDOW)
     {
         if((c = client_getbywin(ev->window))) {
-            client_focus(c);
-            client_raise(c);
+            luaA_object_push(globalconf.L, c);
+            luaA_object_emit_signal(globalconf.L, -1, "request::activate", 0);
+            lua_pop(globalconf.L, 1);
         }
     }
 

lib/awful/ewmh.lua.in

@@ -12,6 +12,7 @@ local math = math
 
 --- Implements EWMH requests handling.
 -- awful.ewmh
+local ewmh = {}
 
 local data = setmetatable({}, { __mode = 'k' })
 
@@ -131,10 +132,23 @@ local function border_change(window)
     end
 end
 
+-- Activate a window
+function ewmh.activate(c)
+    if c:isvisible() then
+        client.focus = c
+        c:raise()
+    else
+        c.urgent = true
+    end
+end
+
+client.connect_signal("request::activate", ewmh.activate)
 client.connect_signal("request::maximized_horizontal", maximized_horizontal)
 client.connect_signal("request::maximized_vertical", maximized_vertical)
 client.connect_signal("request::fullscreen", fullscreen)
 client.connect_signal("property::screen", screen_change)
 client.connect_signal("property::border_width", border_change)
 
+return ewmh
+
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80

objects/client.c

@@ -2401,6 +2401,7 @@ client_class_setup(lua_State *L)
     signal_add(&client_class.signals, "property::window");
     signal_add(&client_class.signals, "property::x");
     signal_add(&client_class.signals, "property::y");
+    signal_add(&client_class.signals, "request::activate");
     signal_add(&client_class.signals, "request::fullscreen");
     signal_add(&client_class.signals, "request::maximized_horizontal");
     signal_add(&client_class.signals, "request::maximized_vertical");