Mount fuse filesystems in one mountpoint using or logic

fuse-or.sh

#! /bin/bash

# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What The Fuck You Want
# To Public License, Version 2, as published by Sam Hocevar. See
# http://sam.zoy.org/wtfpl/COPYING for more details.

readonly FUSE_OR_BIN="$0"

# fuse-or.mount template mountPoint root
fuse-or.mount() {
  local mountPoint="${2//|/\|}"
  local rootDir="${3//|/\|}"
  $(echo "$1" | sed -r                                          \
                  -e "s,(^|[^@])@m@([^@]|$),\1$mountPoint\2,g"  \
                  -e "s,(^|[^@])@r@([^@]|$),\1$rootDir\2,g"     \
                  -e "s|@@r@@|@r@|g"                            \
                  -e "s|@@m@@|@m@|g"
  )
}

# fuse-or.main template mountPoint root1 [root2...]
fuse-or.main() {
  if (( $# < 4 )); then
    cat << EOF
Usage: $FUSE_OR_BIN template mountPoint root1 [root2]...

Arguments:

  template      mount program template. @m@ is replaced by the destination mountpoint and @r@ by the source root directory of the mountpoint
  mountPoint    destination mount point
  root          source root directory

Example

  Try mounting through ssh in \$HOME/media/remotedata myserver:/data. If it fails, try mounting myserver.local:/data and so on:
    $FUSE_OR_BIN 'sshfs @r@ @m@' "\$HOME/media/remotedata" "myserver:/data" "myserver.local:/data" "192.168.0.2:/data"

EOF
    return 2
  fi
  # Read arguments
  local template="$1"
  local mountPoint="$2"
  shift 2
  local result=1
  
  # Loop through arguments until the first success
  until (( $# <= 0 )) || (fuse-or.mount "$template" "$mountPoint" "$1" && echo "$1 on $mountPoint succeeded" && result=0); do
    echo "$1 on $mountPoint failed"
    shift
  done
  
  return $result
}

fuse-or.main "$@"