fetchsingular

#!/bin/sh -e
#
# SingularInterface: A GAP interface to Singular
#
# Copyright of SingularInterface belongs to its developers.
# Please refer to the COPYRIGHT file for details.
#
# SPDX-License-Identifier: GPL-2.0-or-later


VERSION=4.1.2
PATCHLEVEL=p1
TARFILE=singular-$VERSION$PATCHLEVEL.tar.gz
URL=http://www.mathematik.uni-kl.de/ftp/pub/Math/Singular/SOURCES/4-1-2/$TARFILE
MD5=14a2966b652bcb020364c6824cd0de6d

mkdir -p singular

# Download
if [ -e $TARFILE ] ; then
    echo "Checking for $TARFILE... found existing file, using that"
    # TODO: add a checksum check?
elif command -v wget >/dev/null 2>&1 ; then
    echo "Checking for $TARFILE... downloading with wget"
    wget $URL
elif command -v curl >/dev/null 2>&1 ; then
    echo "Checking for $TARFILE... downloading with curl"
    curl -O $URL
else
    echo "Checking for $TARFILE... not found and unable to download"
    echo
    echo "Please manually download the following file:"
    echo "  $URL"
    echo "Put it into the SingularInterface directory and re-run this script."
    exit 1
fi

# Verify checksum
echo "Verifying MD5 checksum of $TARFILE..."
if command -v md5 >/dev/null 2>&1 ; then
    COMPUTED_MD5=`md5 $TARFILE`
elif command -v md5sum >/dev/null 2>&1 ; then
    COMPUTED_MD5=`md5sum $TARFILE`
elif command -v openssl >/dev/null 2>&1 ; then
    COMPUTED_MD5=`openssl md5 $TARFILE`
else
    COMPUTED_MD5=skip
fi
case $COMPUTED_MD5 in
   skip) echo "   could not compute MD5 checksum, skipping test" ;;
   *$MD5* ) echo "   valid MD5 checksum" ;;
   *)  echo "  invalid MD5 checksum, aborting"
       exit 1
       ;;
esac

# Extract
tar xvf $TARFILE

# Move output to right place
rm -rf singular/src
mv singular-$VERSION singular/src