zs.sh - ZipS: Choose the best compression.

zs.sh

#!/usr/bin/env bash
#
# zs.sh - ZipS: Choose the best compression
# Copyright (c) 2018 Koichi OKADA. All rights reserved.
# This script is distributed under the MIT license.
#

(( 5 <= DEBUG )) && set -x

function usage ()
{
  cat<<-EOD
	Usage: ${0##*/} [options] [files ...]
	Options:
	  -h, --help
	  -f, --force
	  -p, --progress
	  -v, --verbose
	EOD
}

function optparse ()
{
  ARGS=()
  while (( 0 < $# )); do
    case "$1" in
      -h|--help)
        OPT_HELP="$1"
        shift
        ;;
      -f|--force)
        OPT_FORCE="$1"
        shift
        ;;
      -p|--progress)
        OPT_PROGRESS="$1"
        shift
        ;;
      -v|--verbose)
        OPT_VERBOSE="$1"
        shift
        ;;
      --)
        ARGS+=( "${@:2}" )
        shift $#
        ;;
      -*)
        error "Unknown option: $1"
        exit 1
        ;;
      *)
        ARGS+=( "$1" )
        shift
        ;;
    esac
  done

  if [ -n "$OPT_HELP" ]; then
    usage
    exit
  fi
} 



SGR_reset="\e[0m"
SGR_bold="\e[1m"
SGR_red="\e[31m"
SGR_green="\e[32m"
SGR_yellow="\e[33m"
EL="\e[K"

function error ()
{
  echo -e "${SGR_red}${SGR_bold}Error:${SGR_reset} $@"
} >&2

function warning ()
{
  echo -e "${SGR_yellow}${SGR_bold}Warning:${SGR_reset} $@"
} >&2



function prepare ()
{
  local i
  
  ZS=()
  _ZS=( GZIP BZIP2 XZ LZO LZ4 BROTLI ZSTD )
  GZIP=(   gzip    .gz  {1..9} )
  BZIP2=(  bzip2   .bz2 {1..9} )
  XZ=(     xz      .xz  {1..9} )
  LZO=(    lzop    .lzo {1..9} )
  LZ4=(    lz4     .lz4 {1..9} )
  BROTLI=( brotli  .br  {1..9} )
  ZSTD=(   zstd    .zst {1..19} )
  
  GZIP_OPT=(   -q )
  BZIP2_OPT=(  -q )
  XZ_OPT=(     -q )
  LZO_OPT=(    -q )
  LZ4_OPT=(    -q )
  BROTLI_OPT=(    )
  ZSTD_OPT=(   -q )
  
  EXTS=()
  
  for i in "${_ZS[@]}"; do
    if eval "which \${${i}[0]} >&/dev/null"; then
      ZS+=( "$i" );
      eval "EXTS+=( \"\${${i}[1]}\" )"
    fi
  done
}

function zs ()
{
  local i Z ZZ
  local SIZE CMD OPT EXT LEV
  
  local MINSIZE=$( stat -c %s "$1" )
  local MINCMD=( true )
  local MINEXT=
  local PARAM=()
  
  if [ -z "$OPT_FORCE" ]; then
    for EXT in "${EXTS[@]}"; do
      if [ -e "$1$EXT" ]; then
        warning "Compressed file already exists: $1$EXT"
        echo "Skip it."
        return 1
      fi
    done
  fi
  
  for ZZ in "${ZS[@]}"; do
    eval "Z=(   \"\${${ZZ}[@]}\" )"
    eval "OPT=( \"\${${ZZ}_OPT[@]}\" )"
    CMD=( "${Z[0]}" "${OPT[@]}" )
    EXT="${Z[1]}"
    LEV=( "${Z[@]:2}" )
    for i in "${LEV[@]}"; do
      "${CMD[@]}" -$i -f -k "$1"
      SIZE=$( stat -c %s "$1$EXT" ) 
      rm "$1$EXT"
      if (( SIZE < MINSIZE )); then
        MINSIZE=$SIZE
        MINCMD=( "${CMD[@]}" )
        MINEXT=$EXT
        PARAM=( -$i -f )
      fi
      [ -n "$OPT_PROGRESS" ] && printf "${EL}%-6s %2d %'16d %s\r" "$CMD" "$i" "$SIZE" "$1$EXT"
    done
  done
  "${MINCMD[@]}" "${PARAM[@]}" "$1"
  [ -n "$OPT_PROGRESS" -o -n "$OPT_VERBOSE" ] && printf "${EL}%-6s %2d %'16d %s\n" "$MINCMD" "${PARAM:1}" "$MINSIZE" "$1$MINEXT"
}



optparse "$@" 
set -- "${ARGS[@]}"
prepare
for i; do zs "$i"; done