Re: http getpass function in msysgit

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 4, 2010, 01:28 UTC
Message-ID: <7vaavp3i2n.fsf@alter.siamese.dyndns.org>
In-Reply-To: <1976ea661002022148s544be10bie912295e04189864@mail.gmail.com>

Frank Li <lznuaa@gmail.com> writes:

Show 7 quoted lines

> You can choose environment name you like. I choose HTTP_ASKPASS just
> because getpass only used at http.c
> ssl_cert_password = getpass("Certificate Password: ");
>
> OpenSSH is separated application and use own SSH_ASKPASS to ask password ...
>
> May GIT_ASKPASS is optional name.

If that is the case, probably it is easiest for the end users if you arrange it this way:

 - If GIT_ASKPASS is not set:

   - If SSH_ASKPASS is present, then use that from getpass() for any and
     all places that would want to get "password" like things;

   - Otherwise consult the terminal as before;

 - If GIT_ASKPASS is set:

   - If SSH_ASKPASS is not set, then export the value of GIT_ASKPASS as
     such as well, so that whenever we spawn "ssh", the same GIT_ASKPASS
     program will be used as a fallback.

That way, if the user already has set up SSH_ASKPASS, we will use the same familiar dialog without forcing the user do anything extra. If the user only sets GIT_ASKPASS without doing SSH_ASKPASS, we would also use it to drive the ssh session. In either case, the user doesn't need to worry about multiple configuration or dialog interface.

> It is nice to use one dialog for all cases. git-svn also have the same problem.

People often seem to use "/usr/lib{,exec}/openssh/gnome-ssh-askpass" as SSH_ASKPASS. It takes the prompt from its command line argument, reads the input, and spits it out to its standard output so that calling program can capture it. It would be a good interface to conform to to minimize the work we need to support this.