lib/common - library of common functions used in my personal

#!/bin/bash
#
# lib/common - library of common functions used in my personal scripts
#
#    Copyright (C) 2011 Rodrigo Silva - <[email protected]>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.


exec 3> /dev/null # to avoid harcoding /dev/null everywhere. For tools' stderr.

SELF="${0##*/}" # buitin $(basename $0)


# _TestRequirements() { #TODO }

testroot()
{
    # simple root test
    [[ "$(id -u)" -eq 0 ]] || fatal "You must run this as root"
}

confirm()
{
    # For both default parameter and user input,
    # non-empty garbage will always evaluate to and behave as NO
    local message="$1"
    local default="${2:-y}"
    local silentno="$3"

    local question="NO" ; [[ "$default" = "y" ]] && question="YES"

    if [ -z "$FORCE" ] ; then

        read -p "$message (y/n, default $question): " confirm
        confirm="${confirm:-$default}"

        case "$confirm" in
        [Yy]*) ;;
        *    ) [[ "$VERBOSE" && -z "$silentno" ]] && \
                 echo "$SELF: ${COMMAND:+$COMMAND: }cancelled by user"
               return 2 ;;
        esac

    fi

    return 0
}

fatal()
{
    local message="$1"
    local errorcode="${2:-1}"
    local dump="$3"

    [[ -n "$dump"    ]] && echo "$dump" >&2
    [[ -n "$message" ]] && echo "$SELF: ${COMMAND:+$COMMAND: }${message/%[[:punct:]]/}" >&2

    exit $errorcode
}

fatalgui()
{
    local message="$1"
    local errorcode="${2:-1}"
    local dump="$3"

    zenity --error --title="$SELF_GUI" \
           --text="${message:+$message\n\n}${dump:+$dump\n\n}"
                 #"Exiting with error code ${errorcode}"

    fatal "$message" "$errorcode" "$dump"
}

min() { (( $1 < $2 )) && printf %d "$1" || printf %d "$2"; }
max() { (( $1 > $2 )) && printf %d "$1" || printf %d "$2"; }

debug()
{
    local var="$1"
    declare -p var
    exit
}

xdg-data-list()
{
    local path="$1"
    local user
    local system
    local folder
    local list=()

    IFS=: read -ra system <<< "${XDG_DATA_DIRS:-/usr/local/share/:/usr/share/}"

    for folder in "${system[@]}" ; do
        if [[ -e "$folder/$path" ]] ; then
            list+=("${folder%/}/$path")
        fi
    done

    user="${XDG_DATA_HOME:-$HOME/.local/share}/$path"
    [[ -e "$user" ]] && list+=("$user")

    xdg_data_list_RESULT=("${list[@]}")
}

xdg-data-cat()
{
    local path="$1"

    xdg-data-list "$path"
    cat "${xdg_data_list_RESULT[@]}"
    unset xdg_data_list_RESULT
}