commit c21d6eaf97dbcc03bbf6bd90096349dba8e1b071
from: Omar Polo <op@omarpolo.com>
date: Thu Oct 08 08:59:12 2020 UTC

grabkey only on the targeted windows

now we grabkey() only on the window that matches what the user
requested.  That is, given

        match class 'Firefox'
        on "C-n" do "<Down>"

we only bind C-n on windows that match the class Firefox, and not on
the root window as we did before.

In order to do this, we traverse the tree during startup and grabkey
on matching windows, than we subscribe also to SubstructureNotify so
that when a window gets mapped we receive an event.

There are still some downsides to this.  Firefox uses also
'/usr/local/lib/firefox/firefox' as class name on my machine, and
sometimes it seems like we don’t grab the key at the first try (maybe
Firefox changes the class after the window gets mapped?)

commit - c85d4bf338efd6371825dfe51680c62ee65be408
commit + c21d6eaf97dbcc03bbf6bd90096349dba8e1b071
blob - 1bfeb83ff93c564131f3b33e7cced7fa172bd3c6
blob + 03c56368be172e377ef948d27abdff49bfa924d4
--- star-platinum.c
+++ star-platinum.c
@@ -119,8 +119,6 @@ int
 main(int argc, char **argv)
 {
 	int status = 0, dump_config = 0, conftest = 0, ch;
-	struct group *g;
-	struct rule *r;
 	XEvent e;
 	Window root;
 
@@ -182,12 +180,9 @@ main(int argc, char **argv)
 
 	root = DefaultRootWindow(d);
 
-	/* grab all the keys */
-	for (g = config; g != NULL; g = g->next)
-		for (r = g->rules; r != NULL; r = r->next)
-			grabkey(r->key, root);
+	grabkey_matching_windows();
 
-	XSelectInput(d, root, KeyPressMask);
+	XSelectInput(d, root, SubstructureNotifyMask | KeyPressMask);
 	XFlush(d);
 
 	pledge("stdio proc exec", NULL);
@@ -200,6 +195,20 @@ main(int argc, char **argv)
 			process_event(config, (XKeyEvent*)&e);
 			break;
 
+		case MapNotify: {
+			XMapEvent *ev = (XMapEvent*)&e;
+			grab_matching_keys(ev->window);
+			break;
+		}
+
+		case UnmapNotify:
+		case ConfigureNotify:
+		case CreateNotify:
+		case DestroyNotify:
+		case ClientMessage:
+			/* ignored */
+			break;
+
 		default:
 			printf("Unknown event %d\n", e.type);
 			break;
@@ -233,7 +242,42 @@ grabkey(struct key k, Window w)
 		XGrabKey(d, XKeysymToKeycode(d, k.key),
 		    k.modifier | ignored_modifiers[i],
 		    w, False, GrabModeAsync, GrabModeAsync);
+	}
+}
+
+void
+grab_matching_keys(Window w)
+{
+	XClassHint ch;
+	struct group *g;
+	struct rule *r;
+
+	if (!XGetClassHint(d, w, &ch))
+		return;
+
+	for (g = config; g != NULL; g = g->next) {
+		if (!group_match(g, w))
+			continue;
+
+		for (r = g->rules; r != NULL; r = r->next)
+			grabkey(r->key, w);
 	}
+}
+
+int
+grabkey_matching_windows()
+{
+	Window root, parent, *children;
+	unsigned int len, i;
+
+	root = DefaultRootWindow(d);
+	if (!XQueryTree(d, root, &root, &parent, &children, &len))
+		return 0;
+
+	for (i = 0; i < len; ++i)
+		grab_matching_keys(children[i]);
+
+	return 1;
 }
 
 KeySym
blob - 96277b5de8bfaf10a929c1180880cf9968434770
blob + b92ba21cc0b1deba1173fa6d36119ab63c25a0af
--- star-platinum.h
+++ star-platinum.h
@@ -91,6 +91,8 @@ int			 group_match(struct group*, Window);
 /* xlib-related */
 int			 error_handler(Display*, XErrorEvent*);
 void			 grabkey(struct key, Window);
+void			 grab_matching_keys(Window);
+int			 grabkey_matching_windows();
 KeySym			 keycode_to_keysym(unsigned int);
 Window			 focused_window();
 void			 send_fake(Window, struct key, XKeyEvent*);