In the changes around commit 420fe75552, I made the terminal
suspend output processing while it waited for a term_size() callback
in response to a resize request. Because on X11 there are unusual
circumstances in which you never receive that callback, I also added a
last-ditch 5-second timeout, so that eventually we'll resume terminal
output processing regardless.
But the timeout lives in terminal.c, in the cross-platform code. This
is pointless on Windows (where resize processing is synchronous, so we
always finish it before the timer code next gets called anyway), but I
decided it was easier to keep the whole mechanism in terminal.c in the
absence of a good reason not to.
Now I've found that reason. We _also_ generate window resizes locally
to the GTK front end, in response to the key combinations that change
the font size, and _those_ still have an asynchrony problem.
So, to begin with, I'm refactoring the request_resize system so that
now there's an explicit callback from the frontend to the terminal to
say 'Your resize request has now been processed, whether or not you've
received a term_size() call'. On Windows, this simplifies matters
greatly because we always know exactly when to call that, and don't
have to keep a 'have we called term_size() already?' flag. On GTK, the
timing complexity previously in terminal.c has moved into window.c.
No functional change (I hope). The payoff will be in the next commit.
4da67d8fa6