#!/bin/sh

# debug is off by default.  Set AD1_SSH_DEBUG

debug=${AD1_SSH_DEBUG:-}

env=$HOME/.ssh/env


#
# check wether
#
#  $env exists
#  $env is sane
#  environment is set
#  environment is sane
#  agent is running
#  agent holds identity
#

ssh-add -l > /dev/null 2>&1
if test $? != 2
then
    # no need to add new agent
    exit 0
fi

if test -f $env
then
    . $env > /dev/null
    # check freshness of $env
    pid=`pgrep -n -U $LOGNAME ssh-agent`
    if test \( -n "${SSH_AGENT_PID}" \) -a \( "${SSH_AGENT_PID}" = "${pid}" \)
    then
        test -n "$debug" && echo >&2 running agent found in $env
    else
        test -n "$debug" && echo >&2 starting agent
        ssh-agent > $env 2>/dev/null
        . $env > /dev/null
    fi
fi

# TODO : do something sane in case $env does not exist

if ssh-add -l | grep 'no identities' > /dev/null
then
   # test -n "$debug" && echo >&2 adding identity to agent
   # test -n "$debug" && echo >&2 you should now add an identity to your agent
   echo >&2 no identities in agent.  aargh
   # exec ssh-add
fi

if test \( -n "$SSH_AUTH_SOCK" \) -a \( -n "$SSH_AGENT_PID" \)
then
    echo "SSH_AUTH_SOCK=$SSH_AUTH_SOCK; export SSH_AUTH_SOCK;"
    echo "SSH_AGENT_PID=$SSH_AGENT_PID; export SSH_AGENT_PID;"
fi

exit 0

POD=<<'EOPOD'

=pod

=head1 NAME

ssh-attach - attach to running ssh-agent

=head1 SYNOPSIS

eval `ssh-attach`

=head1 DESCRIPTION

B<ssh-attach> attaches to a running ssh-agent.  If no agent is found, it
creates one.  It uses the file C<~/.ssh/env> to store state.

=head1 ENVIRONMENT

Set AD1_SSH_DEBUG to '1' to enable debugging.  Set it to '' to disable this.
Per default, debugging is off.

=head1 BUGS

B<ssh-attach> does i<not> yet behave sanely in case no running agent is found.
To bootstrap this tool, run

 % killall ssh-agent
 % ssh-agent > .ssh/env 
 % . .ssh/env
 % ssh-add

.

=head1 FILES

~/.ssh/env: used to store ssh-agent environment.

=head1 SEE ALSO

http://www.cvrti.utah.edu/~dustman/no-more-pw-ssh/
http://www.interactive.co.uk/~rjc/FreeBSD/ssh_agent.html

=head1 VERSION

$Id: ssh-attach,v 1.10 2004/01/25 16:18:08 joostvb Exp $ , under version control
on $Source: /var/cvs/ad1810.com/packages/ad1810-ssh/script/ssh-attach,v $

=head1 COPYRIGHT

Copyright 2003 Joost van Baal <joostvb-ssh-attach-2@mdcc.cx>

This script is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

A copy of the GNU General Public License is available from
http://www.gnu.org/copyleft/gpl.html, or write to the Free Software 
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.

=head1 THANKS

Rudi Sluijtman, Joost Kooij, Arjan de Vet, Jos Backus (and possibly others),
for writing an earlier (non-free) ssh-attach implementation for Origin
in Eindhoven, The Netherlands.

=head1 AUTHOR

Joost van Baal <joostvb-ssh-attach-2@mdcc.cx>

=cut

EOPOD