vagrant-reset-user.sh

#!/bin/sh
# Change UID and GID of vagrant user to $1 and $2.
#
# Using this script can reduce permission-related difficulties when using the
# container.  Without this, if the host UID/GID does not match the container's,
# then ACLs have to be used to permit files created on the host to be read by
# the guest and vice-versa.
set -e

SRC_USER=vagrant
SRC_GROUP=vagrant

current_uid(){
  getent passwd $SRC_USER | cut -d: -f3
}

current_gid(){
  getent group $SRC_GROUP | cut -d: -f3
}

change_uid(){
  old_uid="$1"
  new_uid="$2"

  echo "Migrating $SRC_USER uid from $old_uid to $new_uid ..."

  (set -x; usermod -u $new_uid $SRC_USER; )
  (set -x; find / -xdev -user $old_uid -exec chown -h $new_uid {} \;; )
}

change_gid(){
  old_gid="$1"
  new_gid="$2"

  echo "Migrating $SRC_GROUP gid from $old_gid to $new_gid ..."

  if ! getent group $new_gid >/dev/null; then
    # Simple case, desired GID is unused, move vagrant group to it
    (set -x; groupmod -g $new_gid $SRC_GROUP; )
  else
    # More complex case, desired GID is already used.
    # So, move vagrant user into that group, but also keep it in the
    # vagrant group so it doesn't lose anything.
    echo "($new_gid already exists, making it $SRC_USER's primary group...)"
    (set -x; usermod -g $new_gid -G $SRC_GROUP -a $SRC_USER; )
  fi
  (set -x; find / -xdev -group $old_gid -exec chgrp -h $new_gid {} \;; )
}

run() {
  old_uid=$(current_uid)
  old_gid=$(current_gid)
  new_uid="$1"
  new_gid="$2"

  if test "$new_uid" != "$old_uid"; then
    change_uid $old_uid $new_uid
  fi
  if test "$new_gid" != "$old_gid"; then
    change_gid $old_gid $new_gid
  fi
}

run "$1" "$2"