zssh

#!/bin/bash
#
# A utility for logging into hosts in the local domain by looking up a
# substring of their hostname in the local multicast DNS i.e. using
# zeroconf. The lookup is performed by invoking zeroconf-ssh-host and
# taking the first match.
#

# conditional printf
function vftrace() {
    if [[ -n "$VERBOSE" ]]; then
        printf "$@"
    fi
}

PLATFORM=`uname -a`
if [[ ! ${PLATFORM} =~ Darwin ]]; then
    echo "Non-Darwin platforms unsupported!"
    exit 1
fi
if [[ -z "$1" ]]; then
    echo "Usage: $0 <hostname>"
    exit 1
fi

VERBOSE=""

# First process and consume flags
while [[ "$#" -gt 1 ]]; do 
    if [[ "$1" = "-v" ]]; then
        VERBOSE=true
		VERBOSEFLAG="-v"
        vftrace "verbose\n"
        shift
    elif [[ "$1" = "-h" ]]; then
        USEHOSTNAME=true
        vftrace "hostname mode\n"
        shift
    else
        vftrace "\"$1\" unrecognized, ignored\n"
        shift
    fi
done
HOST="$1"
shift
# If the address is of the form user@host then split it at the @
# symbol to get the user and the host separately
if [[ $HOST =~ \@ ]]; then
    # append the @ symbol again to make the construction of the entire
    # address easy later
    SSHUSER=`echo $HOST | awk -F "@" '{print $1}'`\@
    # the hostname is unadorned
    HOST=`echo $HOST | awk -F "@" '{print $2}'`
fi
vftrace "try zeroconf-ssh-host $HOST...\n"
ENTRY=`zeroconf-ssh-host ${VERBOSEFLAG} ${HOST} | grep .local`
if [[ -z "$ENTRY" ]]; then
    echo "Host \"$HOST\" not found\n"
    exit 1
else
	vftrace "zeroconf returned:\n$ENTRY\n"
fi
HN=`echo $ENTRY | awk '{print $5}'` 
IP=`echo $ENTRY | awk '{print $6}'`
vftrace "hostname $HN IP address $IP\n"
if [[ -n "$USEHOSTNAME" ]]; then
    TARGET=$HN
else 
    TARGET=$IP
fi
if [[ -n ${TARGET} ]]; then
    vftrace "Found $TARGET in local domain\n"
    vftrace "Output of \"ssh ${SSHUSER}${TARGET} ${@}\" :\n"
    ssh ${SSHUSER}${TARGET} $@
fi