#! /bin/bash
#
# Running examples:
#
#    $ ./for-group group_name configure
#    $ ./for-group group_name make [-jN]
#
# This is a wrapper for the configure and Make steps designed for a group
# of users (sharing the same group name) using this pipeline on the same
# build directory.
#
# When the configuration (normally done with `./configure') and build
# (normally done with `.local/bin/make') steps are done with this script,
# all the files that are created within the pipeline have these properties:
#
#   1) Group owner will be the group specified in the command-line.
#   2) The permission flags give write access to the group members.
#
# Original author:
#     Mohammad Akhlaghi <mohammad@akhlaghi.org>
# Contributing author(s):
#     Your name <your@email.address>
# Copyright (C) 2019, Mohammad Akhlaghi.
#
# This script 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 script 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.
#
# A copy of the GNU General Public License is available at
# <http://www.gnu.org/licenses/>.





# Script settings
# ---------------
# Stop the script if there are any errors.
set -e





# See if any argument are given at all.
if [   "x$1" = x          ]; then
    echo "$0: At least two arguments are necessary:"
    echo
    echo " To configure:     $ ./for-group group_name configure"
    echo " To build:         $ ./for-group group_name make"
    exit 1
fi





# Make sure the given group is usable.
testfile=".reproducible-pipeline-group-test"
if sg "$1" "echo test > $testfile"; then
    rm $testfile
    if   [ "x$2" = xconfigure ]; then script="./configure"
    elif [ "x$2" = xmake      ]; then script=".local/bin/make $3 $4"
    else
        echo "$0: a third argument is necessary."
        echo "It specifies the action: either 'configure' or 'make'"
        exit 1
    fi
else
    rm $testfile
    echo
    echo "$0: '$1' is not a usable group name!";
    echo "TIP: you can use the 'groups' command to see your groups."
    exit 1
fi





# Define the group, and set the permission so the user and group both have
# read and write permissions. Then run the respective script.
#
# We are also exporting a special variable so `./configure' and Make can
# prepare for sanity checks and avoid re-doing the whole analysis with a
# typo (not using this script properly after configuration).
export reproducible_paper_group_name="$1"
sg "$1" "umask u+r,u+w,g+r,g+w,o-r,o-w,o-x && $script"





# Group writing permissions for dependencies directory
#
# The common build process sets the writing permissions of the installed
# programs/libraries to `755'. So group members can't write over a
# file. This creates problems when another group member wants to update the
# software for example. We thus need to manually add the group writing flag
# to all installed software files.
if [ "x$2" = xconfigure ]; then
    echo "Enabling group writing permission on all installed software..."
    chmod -R g+w .local/;
fi