#!/bin/sh
# $FreeBSD$
#
# Usage: cd /usr/src/contrib/jemalloc
#        ./FREEBSD-upgrade <command> [args]
#
# At least the following ports are required when importing jemalloc:
# - devel/autoconf
# - devel/git
# - devel/gmake
# - textproc/docbook-xsl
# - textproc/libxslt
#
# The normal workflow for importing a new release is:
#
#   cd /usr/src/contrib/jemalloc
#
# Merge local changes that were made since the previous import:
#
#   ./FREEBSD-upgrade merge-changes
#   ./FREEBSD-upgrade rediff
#
# Extract latest jemalloc release.
#
#   ./FREEBSD-upgrade extract <rev>
#
# Fix patch conflicts as necessary, then regenerate diffs to update line
# offsets:
#
#   ./FREEBSD-upgrade rediff
#   ./FREEBSD-upgrade extract <rev>
#
# Do multiple buildworld/installworld rounds.  If problems arise and patches
# are needed, edit the code in ${work} as necessary, then:
#
#   ./FREEBSD-upgrade rediff
#   ./FREEBSD-upgrade extract <rev>
#
# The rediff/extract order is important because rediff saves the local
# changes, then extract blows away the work tree and re-creates it with the
# diffs applied.
#
# Finally, to clean up:
#
#  ./FREEBSD-upgrade clean

set -e
set -x

if [ ! -x "FREEBSD-upgrade" ] ; then
  echo "Run from within src/contrib/jemalloc/" >&2
  exit 1
fi

if [ "x${JEMALLOC_REPO}" = "x" ] ; then
  JEMALLOC_REPO=https://github.com/jemalloc/jemalloc.git
fi

src=`pwd`

jemalloc_tmp="jemalloc.tmp"
tmpdir="${src}/../${jemalloc_tmp}"
bare_repo="${tmpdir}/jemalloc_bare.git"
work="jemalloc_work.git"
work_repo="${tmpdir}/${work}"
namespace_repo="${tmpdir}/jemalloc_namespace.git"
changes="${src}/FREEBSD-changes"

do_fetch() {
  local rev=$1
  if [ ! -d "${bare_repo}" ] ; then
    mkdir -p "${bare_repo}"
    git clone --bare ${JEMALLOC_REPO} ${bare_repo}
  fi
  (
    cd ${bare_repo}
    git fetch origin ${rev}
  )
}

do_extract_helper() {
  local rev=$1
  local repo=$2
  do_fetch ${rev}
  rm -rf ${repo}
  git clone ${bare_repo} ${repo}
  (
    cd ${repo}
    if [ "x${rev}" != "x" ] ; then
      # Use optional rev argument to check out a revision other than HEAD on
      # master.
      git checkout ${rev}
    fi
  )
}

do_autogen() {
  ./autogen.sh --enable-xmalloc --enable-utrace \
    --with-malloc-conf=abort_conf:false \
    --with-xslroot=/usr/local/share/xsl/docbook --with-private-namespace=__ \
    --with-lg-page-sizes=12,13,14,16
}

do_extract_diff() {
  local rev=$1
  local repo=$2
  do_extract_helper ${rev} ${repo}
  (
    cd ${repo}
    # Apply diffs before generating files.
    patch -p1 < "${src}/FREEBSD-diffs"
    find . -name '*.orig' -delete
    # Generate files.
    do_autogen
    gmake dist
  )
}

do_extract_namespace() {
  local rev=$1
  local repo=$2
  do_extract_helper ${rev} ${repo}
  (
    cd ${repo}
    # Generate files.
    do_autogen
    gmake include/jemalloc/internal/private_namespace.h
  )
}

do_extract() {
  local rev=$1
  do_fetch ${rev}
  do_extract_diff ${rev} ${work_repo}
  do_extract_namespace ${rev} ${namespace_repo}
}

do_diff() {
  (
    cd ${work_repo}
    find . -name '*.orig' -delete
    find . -name '*.rej' -delete
    git add -A
    git diff --cached
  ) > FREEBSD-diffs
}

command=$1
shift
case "${command}" in
  merge-changes) # Merge local changes that were made since the previous import.
    rev=`cat VERSION |tr 'g' ' ' |awk '{print $2}'`
    # Extract code corresponding to most recent import.
    do_extract ${rev}
    # Compute local differences to the upstream+patches and apply them.
    (
      cd ${tmpdir}
      diff -ru -X ${src}/FREEBSD-Xlist ${work} ../jemalloc > ${changes} || true
    )
    (
      cd ${work_repo}
      patch -p1 < ${changes} || true
      find . -name '*.orig' -delete
    )
    # Update diff.
    do_diff
    ;;
  extract) # Extract upstream sources, apply patches, copy to contrib/jemalloc.
    rev=$1
    do_extract ${rev}
    # Delete existing files so that cruft doesn't silently remain.
    rm -rf ChangeLog COPYING VERSION doc include src
    # Copy files over.
    tar cf - -C ${work_repo} -X FREEBSD-Xlist . |tar xvf -
    internal_dir="include/jemalloc/internal"
    grep -v ' isthreaded ' \
      "${namespace_repo}/${internal_dir}/private_namespace.h" \
      > "${internal_dir}/private_namespace.h"
    ;;
  rediff) # Regenerate diffs based on working tree.
    do_diff
    ;;
  clean) # Remove working tree and temporary files.
    rm -rf ${tmpdir} ${changes}
    ;;
  *)
    echo "Unsupported command: \"${command}\"" >&2
    exit 1
    ;;
esac