Re: git-gui Error

From: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Date: Feb 14, 2007, 18:09 UTC
Message-ID: <20070214180906.GB21612@auto.tuwien.ac.at>
In-Reply-To: <20070214022200.GB30884@spearce.org>

On Tue, Feb 13, 2007 at 09:22:00PM -0500, Shawn O. Pearce wrote:

Show 25 quoted lines

> Martin Koegler <mkoegler@auto.tuwien.ac.at> wrote:
> > My fault, I had only a too old GIT core (1.4.1) in my path.
> > With the current version, the problem disapears.
> 
> Yea, I figured (much later) it was something like that.  I still
> think there is a bug in git-gui, namely not telling you that it
> requires Git 1.5.x or later if it finds out the 'git' its invoking
> is older than that.  I'll probably patch it tonight, but it won't
> ship that way in 1.5.0.
>  
> > Some notes about using git-gui: 
> > 
> > * Fetching over ssh results in an empty dialog. The password prompt is
> > only shown in the terminal window, which is likly to be hidden by the
> > the main window of git-gui.
> 
> This is a "feature".  I only use git-gui + ssh with an ssh-agent
> and public key authentication, so I never get password prompts.
> Unfortunately Tcl does not permit me to setup bi-directional pipes
> to a process (heck, I can't get both stdout and stderr except by
> going through cat!), and even if it does, I think ssh would demand
> the tty to get the password, thereby bypassing my pipe anyway.
> 
> Basically I don't know how to improve this.  If someone has a bright
> idea, please pass it along!

Well, there are two way:

1) SSH_ASKPASS (see ssh(1))
    If ssh needs a passphrase, it will read the passphrase from the
    current terminal if it was run from a terminal.  If ssh does not
    have a terminal associated with it but DISPLAY and SSH_ASKPASS
    are set, it will execute the program specified by SSH_ASKPASS
    and open an X11 window to read the passphrase.  This is particu-
    larly useful when calling ssh from a .Xsession or related
    script.  (Note that on some machines it may be necessary to
    redirect the input from /dev/null to make this work.)

This require, that a password helper is installed. One implementation is part of every linux distribution (openssh-askpass-gnome).

2) Simulate user (like http://websvn.kde.org/tags/KDE/3.4.3/kdebase/kioslave/fish/fish.cpp?rev=467549&view=auto)

This requires opening a pty and running ssh on the slave of it. Additionally it requires some logic to determine, what type of input ssh requires.

I tried to implement the second way in a C program once. The interpretion of the ssh output is difficult, but I got it working, but after a system upgrade, the logic was not working any more. So I would avoid this.

mfg Martin Kögler