During init, query screen for _NET_ACTIVE_WINDOW and set that client as

active; while we already look at what's under the pointer, use this
information first, then look under the pointer (saving that round-trip).
This restores the active state to a client after restart even if the
pointer is not above it (and of course the pointer is not above another
client).

calmwm.h

@@ -398,7 +398,7 @@ void			 client_lower(struct client_ctx *);
 void			 client_map(struct client_ctx *);
 void			 client_msg(struct client_ctx *, Atom, Time);
 void			 client_move(struct client_ctx *);
-struct client_ctx	*client_init(Window, struct screen_ctx *);
+struct client_ctx	*client_init(Window, struct screen_ctx *, int);
 void			 client_ptrsave(struct client_ctx *);
 void			 client_ptrwarp(struct client_ctx *);
 void			 client_raise(struct client_ctx *);
@@ -564,6 +564,7 @@ void			 xu_ewmh_net_workarea(struct screen_ctx *);
 void			 xu_ewmh_net_client_list(struct screen_ctx *);
 void			 xu_ewmh_net_client_list_stacking(struct screen_ctx *);
 void			 xu_ewmh_net_active_window(struct screen_ctx *, Window);
+Window			 xu_ewmh_get_net_active_window(struct screen_ctx *);
 void			 xu_ewmh_net_wm_desktop_viewport(struct screen_ctx *);
 void			 xu_ewmh_net_wm_number_of_desktops(struct screen_ctx *);
 void			 xu_ewmh_net_showing_desktop(struct screen_ctx *);

client.c

@@ -43,13 +43,13 @@ static int			 client_inbound(struct client_ctx *, int, int);
 struct client_ctx	*curcc = NULL;
 
 struct client_ctx *
-client_init(Window win, struct screen_ctx *sc)
+client_init(Window win, struct screen_ctx *sc, int active)
 {
 	struct client_ctx	*cc;
 	XWindowAttributes	 wattr;
 	int			 mapped;
 	Window			 rwin, cwin;
-	int			 x, y, wx, wy, activate = 0;
+	int			 x, y, wx, wy;
 	unsigned int		 mask;
 
 	if (win == None)
@@ -105,9 +105,9 @@ client_init(Window win, struct screen_ctx *sc)
 		if ((cc->wmh) && (cc->wmh->flags & StateHint))
 			client_set_wm_state(cc, cc->wmh->initial_state);
 	} else {
-		if ((XQueryPointer(X_Dpy, cc->win, &rwin, &cwin,
+		if ((active == 0) && (XQueryPointer(X_Dpy, cc->win, &rwin, &cwin,
 		    &x, &y, &wx, &wy, &mask)) && (cwin != None))
-			activate = 1;
+			active = 1;
 	}
 
 	XSelectInput(X_Dpy, cc->win, ColormapChangeMask | EnterWindowMask |
@@ -145,7 +145,7 @@ out:
 	XSync(X_Dpy, False);
 	XUngrabServer(X_Dpy);
 
-	if (activate)
+	if (active)
 		client_setactive(cc);
 
 	return(cc);

screen.c

@@ -35,7 +35,7 @@ void
 screen_init(int which)
 {
 	struct screen_ctx	*sc;
-	Window			*wins, w0, w1;
+	Window			*wins, w0, w1, active = None;
 	XSetWindowAttributes	 rootattr;
 	unsigned int		 nwins, i;
 
@@ -65,6 +65,7 @@ screen_init(int which)
 	xu_ewmh_net_wm_number_of_desktops(sc);
 	xu_ewmh_net_showing_desktop(sc);
 	xu_ewmh_net_virtual_roots(sc);
+	active = xu_ewmh_get_net_active_window(sc);
 
 	rootattr.cursor = Conf.cursor[CF_NORMAL];
 	rootattr.event_mask = SubstructureRedirectMask |
@@ -77,7 +78,7 @@ screen_init(int which)
 	/* Deal with existing clients. */
 	if (XQueryTree(X_Dpy, sc->rootwin, &w0, &w1, &wins, &nwins)) {
 		for (i = 0; i < nwins; i++)
-			(void)client_init(wins[i], sc);
+			(void)client_init(wins[i], sc, (active == wins[i]));
 
 		XFree(wins);
 	}

xevents.c

@@ -81,7 +81,7 @@ xev_handle_maprequest(XEvent *ee)
 		client_ptrsave(old_cc);
 
 	if ((cc = client_find(e->window)) == NULL)
-		cc = client_init(e->window, NULL);
+		cc = client_init(e->window, NULL, 0);
 
 	if ((cc != NULL) && (!(cc->flags & CLIENT_IGNORE)))
 		client_ptrwarp(cc);

xutil.c

@@ -256,6 +256,22 @@ xu_ewmh_net_active_window(struct screen_ctx *sc, Window w)
 	    XA_WINDOW, 32, PropModeReplace, (unsigned char *)&w, 1);
 }
 
+Window
+xu_ewmh_get_net_active_window(struct screen_ctx *sc)
+{
+	long		*p;
+	Window		 win;
+
+	if ((xu_getprop(sc->rootwin, ewmh[_NET_ACTIVE_WINDOW],
+	    XA_WINDOW, 32, (unsigned char **)&p)) <= 0)
+		return(None);
+
+	win = (Window)*p;
+	XFree(p);
+
+	return(win);
+}
+
 void
 xu_ewmh_net_wm_desktop_viewport(struct screen_ctx *sc)
 {