10seconds_install

#!/bin/bash

# Copyright (C) 2013,2014,2015,2017 Ole Tange and Free Software
# Foundation, Inc.
#
# 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 script downloads the latest version of GNU Parallel, checks
# the signature and installs it.
#
# It first tries to install it globally.
# If that fails, it does a personal installation.
# If that fails, it copies to $HOME/bin
#
# Download and run the script directly by:
#   (wget -O - pi.dk/3 || curl pi.dk/3/ || fetch -o - http://pi.dk/3) | bash

run() {
    # tail on openindiana must be /usr/xpg4/bin/tail
    TAIL=$(echo | tail -n 1 2>/dev/null && echo tail ||
		      (echo | /usr/xpg4/bin/tail -n 1 && echo /usr/xpg4/bin/tail))
    # grep on openindiana must be /usr/xpg4/bin/grep
    GREP=$(echo | grep -vE . 2>/dev/null && echo grep ||
		      (echo | /usr/xpg4/bin/grep -vE . && echo /usr/xpg4/bin/grep))
  # FreeBSD prefers 'fetch', MacOS prefers 'curl', Linux prefers 'wget'
    GET=$(
	(fetch -o /dev/null file:///bin/sh && echo fetch -o -) ||
	    (curl -h >/dev/null && echo curl -L) ||
	    (wget -h >/dev/null && echo wget -qO -) ||
	    echo 'No wget, curl, fetch: Please inform parallel@gnu.org what you use for downloading URLs' >&2
       )
    if test "$GET" = ""; then
	exit 1
    fi

    if ! perl -e 1; then
	echo No perl installed. GNU Parallel depends on perl. Install perl and retry.
	exit 1
    fi

    LANG=C
    LATEST=$($GET http://ftpmirror.gnu.org/parallel |
		    perl -ne '/.*(parallel-\d{8})/ and print $1."\n"' |
		    sort | $TAIL -n1)
    if test \! -e $LATEST.tar.bz2; then
	# Source tar does not exist
	rm -f $LATEST.tar.bz2 $LATEST.tar.bz2.sig
	$GET http://ftpmirror.gnu.org/parallel/$LATEST.tar.bz2 > $LATEST.tar.bz2
	$GET http://ftpmirror.gnu.org/parallel/$LATEST.tar.bz2.sig > $LATEST.tar.bz2.sig
    fi

    # Check signature - in case ftpmirror.gnu.org is compromised
    if gpg -h 2>/dev/null >/dev/null; then
	# GnuPG installed
	# Setup .gnupg/gpg.conf if not already done
	echo | gpg 2>/dev/null >/dev/null
	gpg --keyserver keys.gnupg.net --recv-key FFFFFFF1
	gpg --keyserver keys.gnupg.net --recv-key 88888888
	if gpg --with-fingerprint $LATEST.tar.bz2.sig 2>&1 |
	       $GREP -E '^Primary key fingerprint: BE9C B493 81DE 3166 A3BC  66C1 2C62 29E2 FFFF FFF1|^Primary key fingerprint: CDA0 1A42 08C4 F745 0610  7E7B D1AB 4516 8888 8888' ; then
	    # Source code signed by Ole Tange <ole@tange.dk>
	    # KeyID FFFFFFF1/88888888
	    true
	else
	    # GnuPG signature failed
	    echo
	    echo "The signature on $LATEST.tar.bz2 is wrong. This may indicate that a criminal has changed the code."
	    echo "THIS IS BAD AND THE CODE WILL NOT BE INSTALLED."
	    echo
	    echo "See http://git.savannah.gnu.org/cgit/parallel.git/tree/README for other installation methods."
	    exit 1
	fi
    else
	# GnuPG not installed
	echo "GnuPG (gpg) is not installed so the signature cannot be checked."
	echo "This means that if the code has been changed by criminals, you will not discover that!"
	echo
	echo "Continue anyway? (y/n)"
	read YN </dev/tty
	if test "$YN" = "n"; then
  	    # Stop
  	    exit 2
	else
  	    # Continue
  	    true
	fi
    fi

    bzip2 -dc $LATEST.tar.bz2 | tar xf -
    cd $LATEST || exit 2
    if ./configure && make && make install; then
	echo
	echo GNU $LATEST installed globally
    else
	if ./configure --prefix=$HOME && make && make install; then
	    echo
	    echo GNU $LATEST installed in $HOME/bin
	else
	    mkdir -p $HOME/bin/;
	    chmod 755 src/*;
	    cp src/parallel src/env_parallel* src/sem src/sql src/niceload src/parcat $HOME/bin;
	    echo
	    echo GNU $LATEST copied to $HOME/bin
	fi

	# Is $HOME/bin already in $PATH?
	if echo $PATH | grep $HOME/bin >/dev/null; then
	    # $HOME/bin is already in $PATH
	    true
	else
	    # Add $HOME/bin to $PATH for both bash and csh
	    echo 'PATH=$PATH:$HOME/bin' >> $HOME/.bashrc
	    echo 'setenv PATH ${PATH}:${HOME}/bin' >> $HOME/.cshrc
	fi

	# Is $HOME/share/man already in $MANPATH?
	if echo $MANPATH | grep $HOME/share/man >/dev/null; then
	    # $HOME/share/man is already in $MANPATH
	    true
	else
	    # Add $HOME/share/man to $MANPATH for both bash and csh
	    echo 'MANPATH=$MANPATH:$HOME/share/man' >> $HOME/.bashrc
	    echo 'setenv MANPATH ${MANPATH}:${HOME}/share/man' >> $HOME/.cshrc
	fi
    fi
}

# Make sure the whole script is downloaded before starting
run