Skip to content

Instantly share code, notes, and snippets.

@con-f-use
Last active March 11, 2021 16:07
Show Gist options
  • Save con-f-use/7914e4896f615b926eef63b4739e993f to your computer and use it in GitHub Desktop.
Save con-f-use/7914e4896f615b926eef63b4739e993f to your computer and use it in GitHub Desktop.
Some bash functions I like to use
#!/usr/bin/env bash
getbool() {
local in="${1:-no}"
if [[ "${in^^}" =~ ^(1|Y(ES)?|ON|T(RUE)?|ENABLE(ED)?)$ ]]; then
return 0
fi
return 1
}
usage() {
local DEBUG=${DEBUG:-N}
if [[ "${DEBUG^^}" =~ ^(1|Y(ES)?|ON|T(RUE)?|ENABLE(ED)?)$ ]]; then
set -o xtrace
shopt -s shift_verbose
fi
if [ -z ${NO_STRICT+x} ]; then
set -o errexit -o nounset -o pipefail -o noclobber
fi
for itm in "$@"; do
if [[ "$itm" =~ ^(-h|--help|-help|-\?)$ ]]; then
1>&2 echo "Usage: $description"; exit 0;
fi
done
}
add_to_file () {
local priv=""
if [ ! -w "$1" ]; then
priv="sudo "
fi
if $priv grep -oqF "$2" "$1" &>/dev/null; then return; fi
echo | $priv tee -a "$1" >/dev/null
echo "$2" | $priv tee -a "$1" >/dev/null
while read -r line; do
echo "$line" | $priv tee -a "$1" >/dev/null
done
}
subcommand() {
usage "$@"
cmd=${1:-main}
shift || true
case "$cmd" in
help) usage --help ;;
*)
local stem="${0%.*}"
stem="${stem##*/}"
if [ "$(LC_ALL=C type -t ${SCRIPTNAME:-"$stem"}:${cmd})" = "function" ]; then
${SCRIPTNAME:-"$stem"}:${cmd} "$@";
elif [ "$(LC_ALL=C type -t cmd:${cmd})" = "function" ]; then
cmd:${cmd} "$@"
else
err "unknown command: $cmd"
fi
;;
esac
}
usr_confirm () {
# Usage:
# usr_confirm "Do you even? [Y/n]" [timeout_in_seconds] [answer_on_timeout]
#
local answers="$(expr match "$1" '.*\[\([NnYy]/[NnYy]\)\]')"
if [ -z "$answers" ]; then
err Answer string missing.
fi
local "empty=$(expr match "$answers" '.*\([YN]\)')" # default on enter
if [ -z "$empty" ]; then
empty=N
fi
local tout="${2:-}" # length of timeout
if [ ! -z "$tout" ]; then tout="-t$tout"; fi
local tmout="${3:-N}" # default on timeout?
if [[ -t 0 ]]; then
read $tout -n 1 -p "$1 " do_it ||
do_it="$tmout"
fi
echo
if [[ $do_it =~ ^(y|Y)$ ]]; then
return 0
fi
if [ -z "$do_it" ] && [ "$empty" != "N" ]; then
return 0
fi
return 1
}
_msg() {
echo -en "[$1: $(date '+%y-%m-%d %H:%m:%S %:::z')\e[0m]: "; echo "$2"; }
dbg() { if getbool "${DEBUG:-no}"; then 1>&2 _msg "\e[34mDebug" "$*"; fi }
nfo() { _msg "\e[32mInfo " "$*"; }
wrn() { _msg "\e[33mWarn " "$*"; }
err() {
last="${@:$#:$#}"
code=$([[ "$last" =~ [0-9]+ ]] && echo "$last" || echo 1)
1>&2 _msg "\e[31mError" "${*%%$code}"
exit $code
}
if [ "$0" = "$BASH_SOURCE" ]; then
usr_confirm "Answer my question? [N/y]" 5 && echo yes || echo no
dbg This should not be shown
DEBUG=y dbg This should be shown
nfo This is an info
wrn test
err "This is a library and not meant for executing."
fi
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment