vthena

#!/bin/bash
# This wrapper allows easy use of my QEMU VM scripts
###TODO:
### external disks
### qemu help message passthrough 
### experiment script
set -eo pipefail 
trap cleanup SIGINT SIGTERM ERR EXIT
script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd -P)
#fetch defaults
[[ -f $script_dir/vthena.d/.env ]] && source $script_dir/vthena.d/.env

# prints a help message
help() {
  echo "
Usage: vthena command
Deletes VMs and rebases their children if necessary
Available commands:
help            ex: vthena help;                 Prints this message.
clone           ex: vthena clone test;           Clones a vm.
create, new     ex: vthena create linux.iso;     Creates _master vm.
list, ls        ex: vthena ls;                   Lists all created vms (cool tree coming?).
remove, rm      ex: vthena rm ubuntu test        Removes all provided vms.
rename, name    ex: vthena name _master ubuntu;  Renames a given vm.
start, up       ex: vthena start ubuntu;         Starts the given vm.
"

  exit 1
}

# very cheap error logging
die() { 
  echo "$*" >&2 
  exit 2
}

# safely exits in the middle of the script
cleanup() {
  # don't let them quit the quit cleaner
  trap - SIGINT SIGTERM ERR EXIT
  # remove instance marker
  echo "Leaving"
  exit
}

# returns all parameters, minus the given command
removeCommand() {
    args=$(
    for param in ${@:2}; do 
        [[ $param != $1 ]] && echo $param 
    done
    )
    echo $args
    return 0
}

##MAIN
# if they ran this without args, they don't know what this does
[[ $# < 1 ]] && help

# demand non root so disks don't clog /root
([[ $USER == root ]] || [[ $HOME == /root ]]) && \
  die "Using this as root can seriously mess up your system depending on partitions. Switch users."

# VTHENA_DIR is mandatory
[[ -z $VTHENA_DIR ]] && export VTHENA_DIR=$HOME/vthena
[[ ! -d $VTHENA_DIR ]] && (mkdir -p $VTHENA_DIR || die "couldn't make directory:$VTHENA_DIR")

# KVM enjoyers only
[[ -z $(id -nG "$USER" | grep kvm) ]] || #&& \
  die "You need to be a member of the kvm group to use these utilities! Check that you are on Linux and are a part of the kvm group"  

# check each parameter
for param in $@; do
  # compare it to command list
  case $param in
    # if it starts with a hyphen it's an option, ignore it
    -* ) continue ;;
    # otherwise if it's a known command, run the appropriate script
    start )              $script_dir/vthena.d/startVM.sh $(removeCommand $param $@) && exit ;;
    create | new )       $script_dir/vthena.d/createVM.sh $(removeCommand $param $@) && exit ;;
    rename | name )      $script_dir/vthena.d/setMasterImg.sh $(removeCommand $param $@) && exit ;;
    clone )              $script_dir/vthena.d/cloneVM.sh $(removeCommand $param $@) && exit ;;
    remove | rm)         $script_dir/vthena.d/removeVM.sh $(removeCommand $param $@) && exit ;;
    list | ls)           $script_dir/vthena.d/util/listVMs.sh && exit ;;
    run | test )         $script_dir/vthena.d/runExperiment.sh $(removeCommand $param $@) && exit ;;
    key | keygen )       $script_dir/vthena.d/genVMKey.sh $(removeCommand $param $@) && exit ;;
    help ) help ;;
    # else print help message
    ? ) help ;;
  esac
done
# Good Job!
exit 0