diff --git a/.update.sh b/.update.sh
index 06df086..fa8557f 100644
--- a/.update.sh
+++ b/.update.sh
@@ -1,29 +1,32 @@
 #!/bin/bash
 
-export DOTFILES=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+THIS_FILE=$(basename "${BASH_SOURCE}")
+source "$THIS_DIR/tools/common.sh"
+
 # get the specified commit id
 dfs_commit=$(curl -fsSL https://api.beardic.cn/get-var/dfs-commit-id)
 if [[ ${#dfs_commit} != 40 ]]; then
-    echo "Error: invalid commit id."
-    python3 "${DOTFILES}/tools/post-log.py" "[ERROR] update.sh: invalid commit id: ${dfs_commit}"
+    fmt_error "invalid commit id"
+    post_log "ERROR" "$THIS_FILE" "invalid commit id: ${dfs_commit}"
     exit
 fi
 # fetch origin
 cd $DOTFILES
 git fetch
 if [[ -n "$(git status -s)" ]]; then
-    echo "Error: directory not clean."
-    python3 "${DOTFILES}/tools/post-log.py" "[ERROR] update.sh: directory not clean"
+    fmt_error "directory not clean"
+    post_log "ERROR" "$THIS_FILE" "directory not clean"
     exit
 fi
 # update
 if [[ "$(git rev-parse HEAD)" == "$dfs_commit" ]]; then
-    echo "Nothing to do."
-    python3 "${DOTFILES}/tools/post-log.py" "[INFO] update.sh: Nothing to do"
+    fmt_info "nothing to do"
+    post_log "INFO" "$THIS_FILE" "nothing to do"
 else
-    echo "Checking out to commit $dfs_commit ..."
+    fmt_info "checking out to commit $dfs_commit ..."
     git -c advice.detachedHead=false checkout $dfs_commit
     cp ./.update.sh ./update.sh
     chmod +x ./update.sh
-    python3 "${DOTFILES}/tools/post-log.py" "[INFO] update.sh: Checked out to commit $dfs_commit"
+    post_log "INFO" "$THIS_FILE" "checked out to commit $dfs_commit"
 fi
diff --git a/.zshrc2 b/.zshrc2
index c7e852d..084eddd 100644
--- a/.zshrc2
+++ b/.zshrc2
@@ -68,46 +68,32 @@ antigen theme ${ZSH_THEME:-ys}
 antigen apply
 # end of antigen config
 
-# functions
+# env
 export DOTFILES=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+export PATH=$PATH:$DOTFILES/scripts
 
-SUDO=''
-if (( $EUID != 0 )); then
-    SUDO='sudo'
-fi
+# alias
+alias "pls"='sudo $(fc -ln -1)'
+alias "se"='sudo -sE'
+alias "pbd"='ping baidu.com'
+alias "p114"='ping 114.114.114.114'
+alias "p666"='ping6 2001:da8::666'
+case $(bash "$DOTFILES/tools/common.sh" get_os_type) in
+    macos  ) alias l='ls -lAGh -D "%y-%m-%d %H:%M"' ;;
+    *      ) alias l='ls -lAGh --time-style="+%y-%m-%d %H:%M"' ;;
+esac
 
-get_os_type() {
-    case "$(uname -s)" in
-        Darwin*)    ans="MacOS";;
-        CYGWIN*)    ans="Cygwin";;
-        MSYS*  )    ans="MSYS";;
-        Linux* )    ans="Linux";;
-        *)          ans="unknown";;
-    esac
-    echo $ans | tr '[:upper:]' '[:lower:]'
-}
-
-get_linux_dist() {
-    if [ -f /etc/os-release ]; then
-        . /etc/os-release
-        ans=$ID
-    elif type lsb_release >/dev/null 2>&1; then
-        ans=$(lsb_release -si)
-    elif [ -f /etc/lsb-release ]; then
-        . /etc/lsb-release
-        ans=$DISTRIB_ID
-    elif [ -f /etc/debian_version ]; then
-        ans=Debian
-    elif [ -f /etc/SuSe-release ]; then
-        ans=SUSE
-    elif [ -f /etc/redhat-release ]; then
-        ans=RedHat
-    else
-        ans=unknown
-    fi
-    echo $ans | tr '[:upper:]' '[:lower:]'
-}
+# key bindings
+bindkey "^b" beginning-of-line
+bindkey "^e" end-of-line
+bindkey "^[[H" beginning-of-line
+bindkey "^[[F" end-of-line
+bindkey "^[[1~" beginning-of-line
+bindkey "^[[4~" end-of-line
+bindkey "^[OH" beginning-of-line
+bindkey "^[OF" end-of-line
 
+# dfs
 dfs()
 {
     case $1 in
@@ -129,37 +115,7 @@ dfs()
             echo 'Done. Please open a new shell to see the changes.'
             ;;
         cd     ) cd "$DOTFILES" ;;
-        log    ) "$DOTFILES/tools/post-log.py" "$2" ;;
+        log    ) "$DOTFILES/tools/common.sh" "post_log" "INFO" "dfs" "$2" ;;
         *      ) echo "unknown command \"$1\". available: update, force-update, version, reset, cd, log" ;;
     esac
 }
-
-dogo()
-{
-    if [[ -z "$1" || "$1" =~ "-h|--help" ]]; then
-        echo "usage: dogo <container>"
-    else
-        $SUDO docker exec -it $1 zsh
-    fi
-}
-
-# alias
-alias "pls"='sudo $(fc -ln -1)'
-alias "se"='sudo -sE'
-alias "pbd"='ping baidu.com'
-alias "p114"='ping 114.114.114.114'
-alias "p666"='ping6 2001:da8::666'
-case $(get_os_type) in
-    macos  ) alias l='ls -lAGh -D "%y-%m-%d %H:%M"' ;;
-    *      ) alias l='ls -lAGh --time-style="+%y-%m-%d %H:%M"' ;;
-esac
-
-# key bindings
-bindkey "^b" beginning-of-line
-bindkey "^e" end-of-line
-bindkey "^[[H" beginning-of-line
-bindkey "^[[F" end-of-line
-bindkey "^[[1~" beginning-of-line
-bindkey "^[[4~" end-of-line
-bindkey "^[OH" beginning-of-line
-bindkey "^[OF" end-of-line
diff --git a/install.sh b/install.sh
index fdde7cb..993c622 100755
--- a/install.sh
+++ b/install.sh
@@ -1,114 +1,15 @@
 #!/bin/bash
 
-# Color settings
-# Source: https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh
-if [ -t 1 ]; then
-    is_tty() {
-        true
-    }
-else
-    is_tty() {
-        false
-    }
-fi
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+source "$THIS_DIR/tools/common.sh"
 
-supports_truecolor() {
-    case "$COLORTERM" in
-    truecolor|24bit) return 0 ;;
-    esac
-
-    case "$TERM" in
-    iterm           |\
-    tmux-truecolor  |\
-    linux-truecolor |\
-    xterm-truecolor |\
-    screen-truecolor) return 0 ;;
-    esac
-
-    return 1
-}
-
-fmt_fatal() {
-    printf '%sfatal: %s%s\n' "${FMT_BOLD}${FMT_RED}" "$*" "$FMT_RESET" >&2
-    exit
-}
-
-fmt_error() {
-    printf '%serror: %s%s\n' "${FMT_RED}" "$*" "$FMT_RESET" >&2
-}
-
-fmt_warning() {
-    echo "${FMT_YELLOW}warning: $1 ${FMT_RESET}" 
-}
-
-fmt_note() {
-    echo "${FMT_GREEN}$1 ${FMT_RESET}"
-}
-
-setup_color() {
-    # Only use colors if connected to a terminal
-    if ! is_tty; then
-        FMT_RAINBOW=""
-        FMT_RED=""
-        FMT_GREEN=""
-        FMT_YELLOW=""
-        FMT_BLUE=""
-        FMT_BOLD=""
-        FMT_RESET=""
-    return
-    fi
-
-    if supports_truecolor; then
-    FMT_RAINBOW="
-        $(printf '\033[38;2;255;0;0m')
-        $(printf '\033[38;2;255;97;0m')
-        $(printf '\033[38;2;247;255;0m')
-        $(printf '\033[38;2;0;255;30m')
-        $(printf '\033[38;2;77;0;255m')
-        $(printf '\033[38;2;168;0;255m')
-        $(printf '\033[38;2;245;0;172m')
-    "
-    else
-    FMT_RAINBOW="
-        $(printf '\033[38;5;196m')
-        $(printf '\033[38;5;202m')
-        $(printf '\033[38;5;226m')
-        $(printf '\033[38;5;082m')
-        $(printf '\033[38;5;021m')
-        $(printf '\033[38;5;093m')
-        $(printf '\033[38;5;163m')
-    "
-    fi
-
-    FMT_RED=$(printf '\033[31m')
-    FMT_GREEN=$(printf '\033[32m')
-    FMT_YELLOW=$(printf '\033[33m')
-    FMT_BLUE=$(printf '\033[34m')
-    FMT_BOLD=$(printf '\033[1m')
-    FMT_RESET=$(printf '\033[0m')
-}
-# END of color settings
-
-dotfile_path=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
 home_slashes=${HOME//\//\\\/}
-if [[ ! $dotfile_path == ${home_slashes}* ]]; then 
-    fmt_fatal "\"$dotfile_path\" is not under \"$HOME\". aborting ..."
+if [[ ! $DOTFILES == ${home_slashes}* ]]; then 
+    fmt_fatal "\"$DOTFILES\" is not under \"$HOME\". aborting ..."
 fi
-dotfile_home_path=${dotfile_path/${home_slashes}/\~}
-dotfile_relative_path=${dotfile_path#${home_slashes}\/}
-crontab_job="0 * * * * ${dotfile_path}/update.sh"
-
-ask_for_yN()
-{
-    while true; do
-        read -p "${FMT_YELLOW}$1${FMT_RESET} [yN]: " yn
-        case $yn in
-            [Yy]* ) return 1;;
-            [Nn]* ) return 0;;
-            * ) return 0;;
-        esac
-    done
-}
+dotfile_home_path=${DOTFILES/${home_slashes}/\~}
+dotfile_relative_path=${DOTFILES#${home_slashes}\/}
+crontab_job="0 * * * * ${DOTFILES}/update.sh"
 
 insert_if_not_exist()
 {
@@ -211,15 +112,15 @@ install_vim_vundle(){
 
 install_update(){
     fmt_note "installing update.sh ..."
-    cp "${dotfile_path}/.update.sh" "${dotfile_path}/update.sh"
-    chmod +x "${dotfile_path}/update.sh"
+    cp "${DOTFILES}/.update.sh" "${DOTFILES}/update.sh"
+    chmod +x "${DOTFILES}/update.sh"
     fmt_note "running update.sh ..."
-    ${dotfile_path}/update.sh
+    ${DOTFILES}/update.sh
 }
 
 uninstall_update(){
     fmt_note "removing update.sh ..."
-    rm "${dotfile_path}/update.sh"
+    rm "${DOTFILES}/update.sh"
 }
 
 install(){
@@ -229,7 +130,7 @@ install(){
     insert_if_not_exist "${HOME}/.tmux.conf" "source-file ${dotfile_home_path}/.tmux.conf2"
     insert_if_not_exist "${HOME}/.vimrc" "source ${dotfile_home_path}/.vimrc2"
     insert_if_not_exist "${HOME}/.gitconfig" "[include] path = \"${dotfile_home_path}/.gitconfig2\""
-    create_symlink "${dotfile_path}/.ssh/authorized_keys2" "${HOME}/.ssh/authorized_keys2"
+    create_symlink "${DOTFILES}/.ssh/authorized_keys2" "${HOME}/.ssh/authorized_keys2"
     # those that won't be uninstalled in the future
     install_tmux_tpm
     install_vim_vundle
@@ -245,12 +146,12 @@ uninstall(){
         delete_if_exist "${HOME}/.tmux.conf" "source-file ${dotfile_home_path}/.tmux.conf2"
         delete_if_exist "${HOME}/.vimrc" "source ${dotfile_home_path}/.vimrc2"
         delete_if_exist "${HOME}/.gitconfig" "[include] path = \"${dotfile_home_path}/.gitconfig2\""
-        delete_link_if_match "${dotfile_path}/.ssh/authorized_keys2" "${HOME}/.ssh/authorized_keys2"
+        delete_link_if_match "${DOTFILES}/.ssh/authorized_keys2" "${HOME}/.ssh/authorized_keys2"
         fmt_note "done uninstalling!"
     fi
 }
 
-setup_color
+
 case $1 in
     ""|-i ) install ;;
     -r    ) uninstall ;;
diff --git a/scripts/dogo b/scripts/dogo
new file mode 100755
index 0000000..fb071f6
--- /dev/null
+++ b/scripts/dogo
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+DOTFILES=${DOTFILES:-$( cd "$THIS_DIR/.." && pwd )}
+source "$DOTFILES/tools/common.sh"
+
+if [[ -z "$1" || "$1" =~ "-h|--help" ]]; then
+    fmt_info "usage: dogo <container>"
+else
+    $SUDO docker exec -it $1 zsh
+fi
diff --git a/tools/alpine.sh b/tools/alpine.sh
index 960abfb..b2b6aa3 100755
--- a/tools/alpine.sh
+++ b/tools/alpine.sh
@@ -1,9 +1,6 @@
 #!/bin/bash
 
-if [[ $USER != "root" ]]; then
-    echo "must run as root!"
-    exit 1
-fi
+set -e
 
 set_mirror()
 {
diff --git a/tools/common.sh b/tools/common.sh
new file mode 100755
index 0000000..468f24f
--- /dev/null
+++ b/tools/common.sh
@@ -0,0 +1,157 @@
+#!/bin/bash
+
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]:-${(%):-%x}}" )" && pwd )
+export DOTFILES=$( cd "$THIS_DIR/.." && pwd )
+
+SUDO=''
+if (( $EUID != 0 )); then
+    SUDO='sudo'
+fi
+
+# Color settings
+# Source: https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh
+if [ -t 1 ]; then
+    is_tty() {
+        true
+    }
+else
+    is_tty() {
+        false
+    }
+fi
+
+supports_truecolor() {
+    case "$COLORTERM" in
+    truecolor|24bit) return 0 ;;
+    esac
+
+    case "$TERM" in
+    iterm           |\
+    tmux-truecolor  |\
+    linux-truecolor |\
+    xterm-truecolor |\
+    screen-truecolor) return 0 ;;
+    esac
+
+    return 1
+}
+
+fmt_fatal() {
+    printf '%sfatal: %s%s\n' "${FMT_BOLD}${FMT_RED}" "$*" "${FMT_RESET}" >&2
+    exit
+}
+
+fmt_error() {
+    printf '%serror: %s%s\n' "${FMT_RED}" "$*" "${FMT_RESET}" >&2
+}
+
+fmt_warning() {
+    printf '%swarning: %s%s\n' "${FMT_YELLOW}" "$*" "${FMT_RESET}" >&2
+}
+
+fmt_info() {
+    printf '%sinfo: %s\n' "${FMT_RESET}" "$*" >&1
+}
+
+fmt_note() {
+    printf '%s%s%s\n' "${FMT_GREEN}" "$*" "${FMT_RESET}" >&1
+}
+
+setup_color() {
+    # Only use colors if connected to a terminal
+    if ! is_tty; then
+        FMT_RAINBOW=""
+        FMT_RED=""
+        FMT_GREEN=""
+        FMT_YELLOW=""
+        FMT_BLUE=""
+        FMT_BOLD=""
+        FMT_RESET=""
+    return
+    fi
+
+    if supports_truecolor; then
+    FMT_RAINBOW="
+        $(printf '\033[38;2;255;0;0m')
+        $(printf '\033[38;2;255;97;0m')
+        $(printf '\033[38;2;247;255;0m')
+        $(printf '\033[38;2;0;255;30m')
+        $(printf '\033[38;2;77;0;255m')
+        $(printf '\033[38;2;168;0;255m')
+        $(printf '\033[38;2;245;0;172m')
+    "
+    else
+    FMT_RAINBOW="
+        $(printf '\033[38;5;196m')
+        $(printf '\033[38;5;202m')
+        $(printf '\033[38;5;226m')
+        $(printf '\033[38;5;082m')
+        $(printf '\033[38;5;021m')
+        $(printf '\033[38;5;093m')
+        $(printf '\033[38;5;163m')
+    "
+    fi
+
+    FMT_RED=$(printf '\033[31m')
+    FMT_GREEN=$(printf '\033[32m')
+    FMT_YELLOW=$(printf '\033[33m')
+    FMT_BLUE=$(printf '\033[34m')
+    FMT_BOLD=$(printf '\033[1m')
+    FMT_RESET=$(printf '\033[0m')
+}
+# END of color settings
+
+ask_for_yN()
+{
+    while true; do
+        read -p "${FMT_YELLOW}$1${FMT_RESET} [yN]: " yn
+        case $yn in
+            [Yy]* ) return 1;;
+            [Nn]* ) return 0;;
+            * ) return 0;;
+        esac
+    done
+}
+
+post_log()
+{
+    python3 "${DOTFILES}/tools/log.py" "[$1] $2: $3"
+}
+
+get_os_type() {
+    case "$(uname -s)" in
+        Darwin*)    ans="MacOS";;
+        CYGWIN*)    ans="Cygwin";;
+        MSYS*  )    ans="MSYS";;
+        Linux* )    ans="Linux";;
+        *)          ans="unknown";;
+    esac
+    echo $ans | tr '[:upper:]' '[:lower:]'
+}
+
+get_linux_dist() {
+    if [ -f /etc/os-release ]; then
+        . /etc/os-release
+        ans=$ID
+    elif type lsb_release >/dev/null 2>&1; then
+        ans=$(lsb_release -si)
+    elif [ -f /etc/lsb-release ]; then
+        . /etc/lsb-release
+        ans=$DISTRIB_ID
+    elif [ -f /etc/debian_version ]; then
+        ans=Debian
+    elif [ -f /etc/SuSe-release ]; then
+        ans=SUSE
+    elif [ -f /etc/redhat-release ]; then
+        ans=RedHat
+    else
+        ans=unknown
+    fi
+    echo $ans | tr '[:upper:]' '[:lower:]'
+}
+
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    $1 "${@:2}"
+else
+    setup_color
+fi
diff --git a/tools/post-log.py b/tools/log.py
old mode 100755
new mode 100644
similarity index 100%
rename from tools/post-log.py
rename to tools/log.py
diff --git a/tools/msys2.sh b/tools/msys2.sh
index 27812a0..3d41d1c 100755
--- a/tools/msys2.sh
+++ b/tools/msys2.sh
@@ -1,9 +1,6 @@
 #!/bin/bash
 
-if [[ $USER != "root" ]]; then
-    echo "must run as root!"
-    exit 1
-fi
+set -e
 
 set_mirror()
 {
diff --git a/tools/ubuntu.sh b/tools/ubuntu.sh
index c06b6e8..c3d1b92 100755
--- a/tools/ubuntu.sh
+++ b/tools/ubuntu.sh
@@ -1,9 +1,6 @@
 #!/bin/bash
 
-if [[ $USER != "root" ]]; then
-    echo "must run as root!"
-    exit 1
-fi
+set -e
 
 set_mirror()
 {