xauth-user

#!/bin/sh

set -e

if [ $# = 0 ] || [ "$1" = '-h' ] || [ "$1" = '--help' ]; then
  echo "Usage: $0 <user1 to authorise> [ <user2> ... ]"
  exit 0
fi

if [ -z "$DISPLAY" ]; then
  echo "\$DISPLAY not set; aborting." >&2
  exit 1
fi

# Not sure what to do here.  Sometimes we get two results:
# one for MIT-MAGIC-COOKIE-1 and one for XDM-AUTHORIZATION-1.
# In that case, XDM-AUTHORIZATION-1 seems to be the right one
# (presumably because xdm/gdm/kdm was used to login).
cookie="`xauth list $DISPLAY | tail -n 1`"

if [ -z "$cookie" ]; then
  echo "xauth list $DISPLAY failed to return a cookie" >&2
  exit 1
fi

for user in "$@"; do
  echo "Adding '$cookie' for user $user"
  su -c "set -x; unset XAUTHORITY; xauth add $cookie" "$user"
done