thanks for 荆棘的思念(http://tieba.baidu.com/p/4754939962)

abu.sh

#!/bin/bash

function __main__(){
    BACKUP_DIR=${HOME}/.autobackup
    local op=${1}
    shift

    case ${op} in
        "init")
            init ${@}
            return ${?}
            ;;
        "cron")
            cron ${@}
            return ${?}
            ;;
        "add")
            add ${@}
            return ${?}
            ;;
        "remove")
            remove ${@}
            return ${?}
            ;;
        "list")
            list ${@}
            return ${?}
            ;;
        "status")
            status ${@}
            return ${?}
            ;;
        "sync")
            sync ${@}
            return ${?}
            ;;
        "restore")
            restore ${@}
            return ${?}
            ;;
        *)
            showUsage ${@}
            return ${?}
            ;;
    esac
}

# ========== init ==================
function init(){
    git clone ${1} ${BACKUP_DIR}
}

# ========== cron ===========
function cron(){
    crontab -l > /tmp/abu_corntab
    echo "*/30 * * * * $(getFilePath ${0}) sync" >> /tmp/abu_crontab
    crontab /tmp/abu_crontab
}

# ========== add  ==================
function add(){
    local target=${1}
    if checkFile ${target}
    then
        local target_fullpath=$(getFilePath ${target})
        local backup_path=${BACKUP_DIR}/$(generateBackupName ${target_fullpath})

        cp -r ${target_fullpath} ${backup_path}
        # mv ${target_fullpath} ${backup_path}
        # ln -s ${backup_path} ${target_fullpath}
    else
        errcho "${target}: file is not exist or file is a symbolic link"
        return 1
    fi
}

# ========== remove ==================
function remove(){
    local target=${1}
    if checkSymbol ${target}
    then
        local target_fullpath=$(getFilePath ${target})
        local backup_path=${BACKUP_DIR}/$(generateBackupName ${target_fullpath})

        if checkFile ${backup_path}
        then
            rm ${backup_path}
            # rm ${target_fullpath}
            # mv ${backup_path} ${target_fullpath}
        else
            errcho "${target}: backup is not exist"
            return 1
        fi

    else
        errcho "${target}: file is not exist"
        return 1
    fi
}

# =========== list ===================
function list(){
    for backup_file in $(ls ${BACKUP_DIR})
    do
        parseBackupFile ${backup_file}
    done
}

# =========== status ===================
function status(){
    cd ${BACKUP_DIR}
    git status
}

# =========== sync ====================
function sync(){
    cd ${BACKUP_DIR}

    for backup_file in $(ls ${BACKUP_DIR})
    do
        local __target_file__=$(parseBackupFile ${backup_file})
        local target_file=${__target_file__/'${HOME}'/${HOME}}
        rm -r ${backup_file}
        cp -r ${target_file} ${backup_file}
    done

    git add -A
    git commit -a -m "auto backup at $(date)"
    git pull origin master
    git push origin master
}

# =========== restore ================
function restore(){
    for __backup_file__ in $(ls ${BACKUP_DIR})
    do
        local backup_file=${BACKUP_DIR}/${__backup_file__}
        local __target_file__=$(parseBackupFile ${backup_file})
        local target_file=${__target_file__/'${HOME}'/${HOME}}

        local target_dir=$(dirname ${target_file})

        if ! [[ -d ${target_dir} ]]
        then
            mkdir -p ${target_dir}
        fi

        if [[ ${backup_file} -ef ${target_file} ]]
        then
            :
        elif [[ -e ${target_file} ]]
        then
            echo "ignore ${target_file}: file is exist"
        else
            echo "restore ${target_file}"
            # ln -s ${backup_file} ${target_file}
            cp -r ${backup_file} ${target_file}
        fi
    done
}

# =============== usage ====================
function showUsage(){
    cat << EOF
abu <option> [file]

options:
        init        init backup dir at ~/.autobackup with git repository
        cron        add auto sync cron job
        add         track file
        remove      remove tracked file
        list        list add tracked file
        status      show backup dir git status
        sync        sync to git repository
        restore     restore all tracked file to new enviroment
EOF
}

# =============== utils ====================
function checkFile(){
    local file=${1}
    return $((test -f ${file} || test -d ${file}) && (! test -L ${file}); echo $?)
}

function checkSymbol(){
    local file=${1}
    return $((test -f ${file} || test -d ${file}) && (test -L ${file}) ;echo $?)
}

function getFilePath(){
    local current=$(pwd)
    local target=${1}

    if [[ -f ${target} ]]
    then
        local result=$(cd $(dirname ${target}) && pwd)/$(basename ${target})
    elif [[ -d ${target} ]]
    then
        local result=$(cd ${target} && pwd)
    else
        echo 'Impassable!'
        return 1
    fi
    cd ${current}
    echo ${result}
}

function generateBackupName(){
    local file_path=$(getFilePath ${1})
    echo ${file_path/${HOME}/'${HOME}'} | openssl base64
}

function parseBackupFile(){
    local backup_File=$(basename ${1})
    echo ${backup_File} | openssl base64 -d
}

function errcho(){
    >&2 echo $@
}

# ========== main =================
__main__ ${@}