#!/bin/bash

# Copyright 2024  Patrick J. Volkerding, Sebeka, Minnesota, USA
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

cd $(dirname $0) ; CWD=$(pwd)

PKGNAM=llvm17-compat
VERSION=${VERSION:-17.0.6}
BUILD=${BUILD:-1_slack15.0}

# Automatically determine the architecture we're building on:
if [ -z "$ARCH" ]; then
  case "$(uname -m)" in
    i?86) ARCH=i586 ;;
    arm*) readelf /usr/bin/file -A | egrep -q "Tag_CPU.*[4,5]" && ARCH=arm || ARCH=armv7hl ;;
    # Unless $ARCH is already set, use uname -m for all other archs:
    *) ARCH=$(uname -m) ;;
  esac
  export ARCH
fi

# If the variable PRINT_PACKAGE_NAME is set, then this script will report what
# the name of the created package would be, and then exit. This information
# could be useful to other scripts.
if [ ! -z "${PRINT_PACKAGE_NAME}" ]; then
  echo "$PKGNAM-$VERSION-$ARCH-$BUILD.txz"
  exit 0
fi

NUMJOBS=${NUMJOBS:-" -j $(expr $(nproc) + 1) "}

if [ "$ARCH" = "i586" ]; then
  SLKCFLAGS="-O2 -march=i586 -mtune=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "i686" ]; then
  SLKCFLAGS="-O2 -march=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "s390" ]; then
  SLKCFLAGS="-O2"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "x86_64" ]; then
  SLKCFLAGS="-O2 -fPIC"
  LIBDIRSUFFIX="64"
elif [ "$ARCH" = "armv7hl" ]; then
  SLKCFLAGS="-O3 -march=armv7-a -mfpu=vfpv3-d16"
  LIBDIRSUFFIX=""
else
  SLKCFLAGS="-O2"
  LIBDIRSUFFIX=""
fi

TMP=${TMP:-/tmp}
PKG=$TMP/package-$PKGNAM

rm -rf $PKG
mkdir -p $TMP $PKG

# Create a directory for the libraries:
mkdir -p $PKG/usr/lib${LIBDIRSUFFIX}

echo "Copying list of directly-linked libraries..."
cat $CWD/llvm17-list-of-libraries-to-retain | while read library ; do
  if [ ! "$(echo $library | cut -c 1)" = "#" ]; then
    if [ ! -e /usr/lib${LIBDIRSUFFIX}/$library ]; then
      echo "ERROR: llvm 17 package must be installed so that we can extract libraries from the system."
      exit 1
    fi
    cp -a -v /usr/lib${LIBDIRSUFFIX}/$library $PKG/usr/lib${LIBDIRSUFFIX}
    if [ -L /usr/lib${LIBDIRSUFFIX}/$library ]; then
      cp -a /usr/lib${LIBDIRSUFFIX}/$(readlink /usr/lib${LIBDIRSUFFIX}/$library) $PKG/usr/lib${LIBDIRSUFFIX}
    fi
  fi
done || exit 1

echo "Copying other LLVM libraries required by the already copied ones..."
cd $PKG/usr/lib${LIBDIRSUFFIX}
touch $PKG/scan
while [ -e $PKG/scan ]; do
  # we'll reset this flag if we find something. We need to make one pass without
  # finding anything to leave this loop.
  rm $PKG/scan
  for library in lib* ; do
    readelf -d $library | grep "Shared library" | rev | cut -f 1 -d ' ' | rev | tr -d \[ | tr -d \] | grep ".so.17$" | while read dep ; do
      if [ ! -e $dep ]; then
        echo "Copying $dep for $library..."
        cp -a -v /usr/lib${LIBDIRSUFFIX}/$dep $PKG/usr/lib${LIBDIRSUFFIX}
        if [ -L /usr/lib${LIBDIRSUFFIX}/$dep ]; then
          cp -a /usr/lib${LIBDIRSUFFIX}/$(readlink /usr/lib${LIBDIRSUFFIX}/$dep) $PKG/usr/lib${LIBDIRSUFFIX}
        fi
        touch $PKG/scan
      fi
    done
  done
done

mkdir -p $PKG/install
cat $CWD/slack-desc > $PKG/install/slack-desc

cd $PKG
/sbin/makepkg -l y -c n $TMP/$PKGNAM-$VERSION-$ARCH-$BUILD.txz