#!/bin/bash -
# File: tar-home.sh
# Copyright (c) 2018-2019 Justin Hanekom
# Licensed under the MIT License
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
# Setup a safe Bash scripting environment
set -o errexit # Exit immediately if an error occurs
set -o noclobber # Do not allow files to be overwritten via redirect
set -o nounset # Do not allow unset variables
# Set the exit code of a pipeline to the rightmost non-zero on error
set -o pipefail
# Set the internal field separator to newline or tab, but not space
IFS=$'\n\t'
# Setup a secure Bash scripting environment by: setting a secure path;
# clearing all aliases; clearing the command path hash; setting the hard limit
# to 0 to turn off core dumps; and setting a secure umask
PATH=$(PATH='/bin:/usr/bin' getconf PATH); export PATH
builtin unalias -a
hash -r
ulimit -H -c 0 --
UMASK=002
umask ${UMASK}
# Global constant definitions
readonly OPTIONS='u:s:d:p:x:k:rvh'
readonly LONGOPTS='user:,srcdir:,destdir:,prefix:,suffix:,keep:,remove,verbose,help'
readonly TIMESTAMP=$(date '+%Y%m%d%H%M%S')
readonly STARTED_AT=$(date '+%s')
# Global variable declarations
USER_NAME=''
SRC_DIR=''
DEST_DIR=''
PREFIX="home_"
SUFFIX='.tar.gz'
KEEP=5
IS_REMOVE=''
IS_VERBOSE=''
################################################################################
# Function: chomp_slash
# Description: Removes any trailing slash ("/") from a string
# Arguments: $1 :- String from which to remove any trailing slashes
# Ouputs: Prints string with trailing slashes removed
function chomp_slash {
local dir="$1"
while [ "${dir:(-1)}" = '/' ]; do
dir=${dir::-1}
done
echo "${dir}"
}
################################################################################
# Function: echo_if_verbose
# Description: Prints $@ if IS_VERBOSE is not empty
# Arguments: $@ :- Content to echo if ${IS_VERBOSE} is not empty
# Requires: ${IS_VERBOSE} set to a non-empty string if verbose is on
# Outputs: Prints $@ if ${IS_VERBOSE} is not empty
function echo_if_verbose {
if [ -n "${IS_VERBOSE}" ]; then
echo "$@"
fi
}
################################################################################
# Function: trim
# Description: Trims any/all whitespace from the beginning and end of a string
# Arguments: $1 :- The string from which to trim whitespace
# Outputs: Prints string with any leading/trailing whitespace removed
function trim {
local str="$1"
str="${str#"${str%%[![:space:]]*}"}"
str="${str%"${str##*[![:space:]]}"}"
echo "$1"
}
################################################################################
# Function: usage_exit
# Description: Prints the usage message for this script and then exits
# Arguments: $1 :- Exit code; defaults to 1
# Outputs: Prints description of how to call this script
function usage_exit {
local exit_code=1
if [[ ${1-} =~ ^[0-9]+$ ]]; then
exit_code="$1"
fi
cat << EOT
Usage: $(basename "$0") [options]...
-u|--user (Required) The owner of the generated archive file
-s|--srcdir (Required) The owners home directory
-d|--destdir (Required) The dir into which to save the new file
-p|--prefix The prefix of the generated archive file ('home_')
-x|--suffix The suffix of the generated archive file ('.tar.gz')
-k|--keep How many archives to keep (5)
-r|--remove Causes previous archive files to be removed
-v|--verbose Displays verbose output
-h|--help Displays this message and aborts the script
NOTE: The , , and arguments are mandatory
and *must* be supplied
EOT
exit "${exit_code}"
}
################################################################################
# Function: parse_cmdline
# Description: Parses the command-line using the enhanced version of getopt
# Arguments: $@ :- Command-line arguments (required)
# Requires: Global variables $USER_NAME, $SRC_DIR, $DEST_DIR, $PREFIX,
# $SUFFIX, $KEEP, $IS_REMOVE, and $IS_VERBOSE
# Outputs: Sets above-mentioned global variables based on given
# command-line arguments
function parse_cmd_line {
# Ensure that the enhanced version of getopt is available
! getopt --test > /dev/null
if (( "${PIPESTATUS[0]}" != 4 )); then
echo "I'm sorry, the enhanced version of getopt is required. Exiting." >&2
exit 1
fi
# Initialize the global variables
USER_NAME=''
SRC_DIR=''
DEST_DIR=''
PREFIX="home_"
SUFFIX='.tar.gz'
KEEP=5
IS_REMOVE=''
IS_VERBOSE=''
# Parse the command-line options
if ! readonly PARSED_OPTIONS=$(getopt --options=${OPTIONS} \
--longoptions=${LONGOPTS} \
--name "$(basename "$0")" -- "$@"); then
echo 'Unknown error parsing getopt options. Exiting.' >&2
exit 2
fi
eval set -- "${PARSED_OPTIONS}"
# Extract command-line options and their arguments, if any
while (( $# >= 1 )); do
case "$1" in
-u|--user)
USER_NAME=$(trim "$2") ; shift 2
;;
-s|--srcdir)
SRC_DIR=$(chomp_slash "$(trim "$2")") ; shift 2
;;
-d|--destdir)
DEST_DIR=$(chomp_slash "$(trim "$2")") ; shift 2
;;
-p|--prefix)
PREFIX=$(trim "$2") ; shift 2
;;
-x|--suffix)
SUFFIX=$(trim "$2") ; shift 2
;;
-k|--keep)
KEEP=$(trim "$2") ; shift 2
;;
-r|--remove)
IS_REMOVE='true' ; shift
;;
-v|--verbose)
IS_VERBOSE='true' ; shift
;;
-h|--help)
usage_exit 0
;;
--)
shift ; break
;;
*)
usage_exit 3 >&2
;;
esac
done
# Ensure that required options have been supplied
if [[ -z "${USER_NAME}" || -z "${SRC_DIR}" || -z "${DEST_DIR}" ]]; then
usage_exit 4 >&2
fi
} # parse_cmd_line
################################################################################
# Start of program
parse_cmd_line "$@"
# Determine the tar options
readonly DEST_FILENAME="${DEST_DIR}/${PREFIX}${TIMESTAMP}${SUFFIX}"
if [ -n "$IS_VERBOSE" ]; then
readonly VERBOSE='--verbose'
else
readonly VERBOSE=''
fi
readonly FLAGS="--create --preserve-permissions --atime-preserve \
${VERBOSE} --use-compress-program='pigz'"
TAR_CMD="sudo tar ${FLAGS} --file='${DEST_FILENAME}' '$(basename "${SRC_DIR}")'"
[ -z "${IS_VERBOSE}" ] && TAR_CMD="${TAR_CMD} &>/dev/null"
# Optionally keep the last ${KEEP}-1 archives
if [ -n "${IS_REMOVE}" ]; then
files_signature="${DEST_DIR}/${PREFIX}*${SUFFIX}"
if (( "${KEEP}" > 0 )); then
set +e # Temporarily disable error exiting
sudo ls -1tr "${files_signature}" | \
tail +"${KEEP}" | sudo xargs rm --force "${VERBOSE}"
set -e # Reenable error exiting
else
sudo rm --force "${VERBOSE}" "${files_signature}"
fi
fi
exit
# Archive the source directory
#
# Using cd instead of tar's -C (i.e., directory) flag because I was getting
# the unexpected result of only the Desktop directory being archived
# if this script is executed by root's crontab;
# archiving from the $SRC_DIRs parent so that the archive is rooted at the
# $SRC_DIRs basename
pushd . &>/dev/null
cd "$(dirname "${SRC_DIR}")"
eval "${TAR_CMD}" || true
popd &>/dev/null
# Change the owner of the generated archive file
sudo chown "${USER_NAME}":"${USER_NAME}" "${DEST_FILENAME}" 2>/dev/null
echo_if_verbose "Changed owner of: ${DEST_FILENAME} to: ${USER_NAME}"
# Report that we are done, and how long the script took
if [ -n "${IS_VERBOSE}" ]; then
readonly ENDED_AT=$(date '+%s')
readonly DIFF=$(( ENDED_AT - STARTED_AT ))
echo "Done, in ${DIFF} seconds"!
fi
