RenderDo

#!/bin/sh

HostName=render
HostList='1 2 3 4 5 6 7 8 9'
user=wr

ERROR()
{
  echo error: $*
  exit 1
}

USAGE()
{
  [ -z "$1" ] || echo error: $*
  echo usage: $(basename "$0") '<options>' command
  echo '       --help         this message'
  echo '       --verbose      print more information'
  echo '       --host=<hostN> set the maximum host name [render]'
  echo '       --pre=cmd      a local command for the front of the pipe'
  echo '       --post=cmd     a local command for the rear of the pipe'
  echo '       --yes          assume yes'
  echo '       --list=i,n-m   which machines to run command on'
  exit 1
}

ExpandList()
{
  local l h i s f
  l=$(echo $* | sed 's/[[:space:],;]\{1,\}/ /g')
  h=''
  for i in ${l}
  do
    s=${i%%-*}
    f=${i##*-}
    while [ ${s} -le ${f} ]
    do
      h="${h} ${s}"
      s=$((${s} + 1))
    done
  done
  echo ${h}
}


RunCommands()
{
  local user host pre post cmd tag
  user="$1"; shift
  host="$1"; shift
  pre="$1"; shift
  post="$1"; shift

  case "${verbose}" in
    [yY][eE][sS])
      [ -n "${pre}" ] && echo local: ${pre} \|
      echo ${user}@${host}: $*
      [ -n "${post}" ] && echo local: \| ${post}
      ;;
    *)
      case "${brief}" in
        [yY][eE][sS])
          tag="${user}@${host}: "
          ;;
        *)
          tag=''
          ;;
      esac
      ;;
  esac
  if [ -z "${pre}" ]
  then
    if [ -z "${post}" ]
    then
      ssh -l "${user}" "${host}" "$@" | sed "s/^/${tag}/"
    else
      ssh -l "${user}" "${host}" "$@" | sed "s/^/${tag}/" | ${post}
    fi
  else
    if [ -z "${post}" ]
    then
      ${pre} | ssh -l "${user}" "${host}" "$@" | sed "s/^/${tag}/"
    else
      ${pre} | ssh -l "${user}" "${host}" "$@" | sed "s/^/${tag}/" | ${post}
    fi
  fi
}


# main program
# ------------

PreCommand=''
PostCommand=''
verbose=no
brief=no
yorn=''
print=no

getopt=/usr/local/bin/getopt
[ -x "${getopt}" ] || getopt=getopt
args=$(${getopt} -o hvH:bp:o:l:yP --long=help,verbose,host:,brief,pre:,post:,list:,yes,print-list -- "$@") || exit 1
# replace the arguments with the parsed values
eval set -- "${args}"

while :
do
  case "$1" in
    -v|--verbose)
      verbose=yes
      shift
      ;;

    -H|--host)
      HostName="${2%%[0-9]*}"
      n="${2#${HostName}}"
      HostList=''
      i=1
      while [ ${i} -le ${n} ]
      do
        HostList="${HostList} ${i}"
        i=$((${i} + 1))
      done
      shift 2
      ;;

    -P|--print-list)
      print=yes
      shift
      ;;

    -b|--brief)
      brief=yes
      shift
      ;;

    -p|--pre)
      PreCommand=$2
      shift 2
      ;;

    -o|--post)
      PostCommand=$2
      shift 2
      ;;

    -l|--list)
      HostList=$(ExpandList $2)
      shift 2
      ;;

    -y|--yes)
      yorn='all'
      shift
      ;;

    --)
      shift
      break
      ;;

    -h|--help)
      USAGE
      ;;

    *)
      USAGE invalid option: $1
      ;;
  esac
done

#echo verbose = ${verbose}
#echo ARGS = "$@"

case "${print}" in
  [yY]|[yY][eE][sS])
    for i in ${HostList}
    do
      echo ${HostName}${i}
    done
    exit 0
    ;;
  *)
    ;;
esac

[ -z "$1" ] && USAGE missing command


for i in ${HostList}
do
  host="${HostName}${i}"

  [ -z "${yorn}" ] && read -p "Execute ${host}: $* (y/n/a/q)? " yorn junk
  case "${yorn}" in
    [yY]|[yY][eE][sS])
      yorn=''
      RunCommands "${user}" "${host}" "${PreCommand}" "${PostCommand}" "$@"
      ;;
    [aA]|[aA][lL][lL])
      RunCommands "${user}" "${host}" "${PreCommand}" "${PostCommand}" "$@"
      ;;
    [qQ]|[qQ][uU][iI][tT])
      break
      ;;
    *)
      yorn=''
      ;;
  esac
done