Mac OSXでramdisk。${HOME}/.ramdisk に設定ぽいのが書けるようにした。

osx-ramdisk

#!/bin/sh

### check ostype
if [ ! `uname -s` == "Darwin" ]; then
  echo "error : only works with Mac OS X" >&2
  exit 1
fi

### comannd, perse options

help() {
  echo "`basename $0` [ -h ] [ -u ] [ -c filename ]"
  echo "  -h : display this text"
  echo "  -u : unmount ramdisk, unlink symlink"
  echo "  -c : specify the configuration file to use."
}

while getopts "huc:" OPT; do
  case $OPT in
    \?) OPT_ERROR=1; break;;
    h) help && exit ;;
    u) opt_u=true;;
    c) opt_c="$OPTARG";;
  esac
done

shift $(( $OPTIND - 1 ))
[ $OPT_ERROR ] && help && exit 1

ramdisk_laodconfig() {
  rcfile=~/.ramdisk
  if [ -n "${opt_c}" ]; then
    rcfile=${opt_c}
  elif [ ! -f "${rcfile}" ]; then
    cat > ${rcfile} <<_EOT_
## ramdisk config

# volume size (Mb)
RAMDISK_SIZE=512

# volume name
RAMDISK_VOLUME="ramdisk"

# disk id
RAMDISK_HDID=/dev/disk1

# cache target dirs
CACHE_DIRS=( \
~/Library/Caches/Google \
~/Library/Caches/com.apple.iTunes \
~/Library/Caches/com.apple.Safari \
~/Library/Caches/Firefox \
)
_EOT_
  fi
  source ${rcfile}
}

ramdisk_umount() {
  local ramdisk=/volumes/${RAMDISK_VOLUME}
  umount ${ramdisk}
  hdiutil detach ${RAMDISK_HDID}
}

ramdisk_mount(){
  local id=`hdiutil attach -nomount ram://$[RAMDISK_SIZE*1024*1024/512]`
  if [ ${id} == ${RAMDISK_HDID} ]; then
    diskutil eraseDisk HFS+ ${RAMDISK_VOLUME} ${RAMDISK_HDID}
  else
    return 1
  fi
}

ramdisk_make_symlinks() {
  local ramdisk=/volumes/${RAMDISK_VOLUME}
  if [ -d "${ramdisk}" ] && [ -n ${CACHE_DIRS} ]; then
    echo "\nMake symlinks & make backup ...\n"
    for dir in ${CACHE_DIRS[@]}
    do
      mkdir ${ramdisk}/${dir##*/}
      if [ -d ${dir} ]; then
        mv -fv ${dir} ${dir}.bak
      fi
      if [ ! -L ${dir} ]; then
        ln -sfv ${ramdisk}/${dir##*/} ${dir}
      fi
    done
    echo "\n... done!\n"
  else
    return 1
  fi
}

ramdisk_rm_symlinks() {
  local ramdisk=/volumes/${RAMDISK_VOLUME}
  if [ ! -d "${ramdisk}" ] && [ -n ${CACHE_DIRS} ]; then
    echo "\nRemove symlinks & restore backup ...\n"
    for dir in ${CACHE_DIRS[@]}
    do
      if [ -L ${dir} ]; then
        rm -fv ${dir}
      fi
      if [ -d ${dir}.bak ]; then
        mv -fv ${dir}.bak ${dir}
      fi
    done
    echo "\n... done!\n"
  else
    return 1
  fi
}

main() {
  ramdisk_laodconfig
  if [ ${opt_u} ]; then
    ramdisk_umount
    ramdisk_rm_symlinks
  else
    ramdisk_mount && \
    ramdisk_make_symlinks
  fi
}

main