bug#33252: 27.0.50; Recursive password prompt takes over

[Lars Ingebrigtsen]

Juri Linkov <juri@linkov.net> writes:

> A reproducible short test case:
>
> 0. emacs -Q
>
> 1. M-&
>    while true; do echo -n "Password: "; sleep 1; done
>    RET
>
> After 42 seconds Emacs session becomes completely unusable, and control
> can be regained only after killing the shell script from outside Emacs.

I've now added a recursion check to the comint prompting, and it'll stop
adding new prompts when it's ten layers deep, which will allow the user
to kill the shell script.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no