#!/bin/bash
#
# Copyright (C) 2017 Kyle Schwarz
#
# 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 program 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.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

v_script="4.0.1"
v_binutils="2.29.1"
v_gcc="7.3.0"
v_gmp="6.1.2"
v_mpfr="4.0.1"
v_mpc="1.1.0"
v_isl="0.18"

show_help()
{
  cat <<HELP
usage: mingw-w64-build [OPTION]... ARCH...
Build the MinGW-w64 toolchain for ARCH(s) (i686 or x86_64).

  -h, --help     display this help and exit
  --version      output version information and exit

Creates directories 'src' and 'bld' in the current directory and
  removes them when complete.

examples:
  mingw-w64-build i686
  mingw-w64-build x86_64
  mingw-w64-build i686 x86_64
HELP
}

show_version()
{
  cat <<VERSION
mingw-w64-build $v_script
Copyright (C) 2017 Kyle Schwarz
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
VERSION
}

error_exit()
{
  local error_text="$1"
  shift

  if [[ -z "$error_text" ]]; then
    error_text="See 'build.log' for further details."
  fi

  echo "mingw-w64-build: error: $error_text" >&3

  exit 1
}

clean_build()
{
  local build_dir="$1"

  rm -fr "$build_dir"
  mkdir -p "$build_dir"
  cd "$build_dir" || error_exit
}

download_sources()
{
  cd "$src" || error_exit

  echo "downloading mingw-w64-git" >&3
  git clone --depth 1 git://git.code.sf.net/p/mingw-w64/mingw-w64 "mingw-w64-git" || error_exit

  local urls=(
    "http://ftp.gnu.org/gnu/binutils/binutils-$v_binutils.tar.bz2"
    "http://ftp.gnu.org/gnu/gcc/gcc-$v_gcc/gcc-$v_gcc.tar.xz"
    "http://ftp.gnu.org/gnu/gmp/gmp-$v_gmp.tar.xz"
    "http://ftp.gnu.org/gnu/mpfr/mpfr-$v_mpfr.tar.xz"
    "http://ftp.gnu.org/gnu/mpc/mpc-$v_mpc.tar.gz"
    "http://isl.gforge.inria.fr/isl-$v_isl.tar.xz"
  )

  for url in "${urls[@]}"; do
    local archive="${url##*/}"
    local c
    echo "downloading $archive" >&3
    wget -nv "$url" || error_exit
    echo "extracting $archive" >&3
    case "${archive##*.}" in
      gz) c=z ;;
      bz2) c=j ;;
      xz) c=J ;;
    esac
    tar -x${c}f "$archive" || error_exit
  done

  cd "$src/gcc-$v_gcc" || error_exit

  ln -s "../gmp-$v_gmp" "gmp"
  ln -s "../mpfr-$v_mpfr" "mpfr"
  ln -s "../mpc-$v_mpc" "mpc"
  ln -s "../isl-$v_isl" "isl"

  patch -p 1 <<PATCH
diff -uprN a/libstdc++-v3/config/os/mingw32-w64/os_defines.h b/libstdc++-v3/config/os/mingw32-w64/os_defines.h
--- a/libstdc++-v3/config/os/mingw32-w64/os_defines.h   2017-01-01 04:07:43.000000000 -0800
+++ b/libstdc++-v3/config/os/mingw32-w64/os_defines.h   2017-05-25 18:47:52.161016148 -0700
@@ -76,6 +76,7 @@

 #ifdef __x86_64__
 #define _GLIBCXX_LLP64 1
+#define _GLIBCXX_USE_WEAK_REF 0
 #endif

 // Enable use of GetModuleHandleEx (requires Windows XP/2003) in
PATCH
}

build_toolchain()
{
  local host="$1-w64-mingw32"
  local prefix="$wd/$host"
  export PATH="$prefix/bin:$PATH"

  rm -fr "$prefix"

  clean_build "$bld/binutils"
  echo "configuring binutils" >&3
  "../../src/binutils-$v_binutils/configure" --prefix="$prefix" --disable-shared \
    --enable-static --with-sysroot="$prefix" --target="$host" \
    --disable-multilib --disable-nls || error_exit
  echo "building binutils" >&3
  make -j $cpus || error_exit
  echo "installing binutils" >&3
  make install || error_exit

  clean_build "$bld/mingw-w64"
  echo "configuring mingw-w64-headers" >&3
  "../../src/mingw-w64-git/mingw-w64-headers/configure" --build="$build" \
    --host="$host" --prefix="$prefix/$host" --enable-secure-api || error_exit
  echo "installing mingw-w64-headers" >&3
  make install || error_exit
  cd "$prefix" || error_exit
  ln -s "./$host" "./mingw" || error_exit

  clean_build "$bld/gcc"
  echo "configuring gcc" >&3
  "../../src/gcc-$v_gcc/configure" --target="$host" --disable-shared \
    --enable-static --disable-multilib --prefix="$prefix" \
    --enable-languages=c,c++ --disable-nls || error_exit
  echo "running 'make-gcc' for gcc" >&3
  make -j $cpus all-gcc || error_exit
  echo "running 'install-gcc' for gcc" >&3
  make install-gcc || error_exit

  clean_build "$bld/mingw-w64"
  echo "configuring mingw-w64-crt" >&3
  "../../src/mingw-w64-git/mingw-w64-crt/configure" --build="$build" --host="$host" \
    --prefix="$prefix/$host" --with-sysroot="$prefix/$host"
  echo "building mingw-w64-crt" >&3
  make -j $cpus || error_exit
  echo "installing mingw-w64-crt" >&3
  make install || error_exit

  cd "$bld/gcc" || error_exit
  echo "building gcc" >&3
  make -j $cpus || error_exit
  echo "installing gcc" >&3
  make install || error_exit

  return 0
}

while :; do
  case $1 in
    -h|--help)
      show_help
      exit
      ;;
    --version)
      show_version
      exit
      ;;
    -?*)
      echo "mingw-w64-build: error: unknown option: '$1'" >&2
      exit
      ;;
    *)
      break
  esac

  shift
done

if [[ "$PWD" = *" "* ]]; then
  echo "mingw-w64-build: error: working path contains spaces" >&2
  exit 1
fi

if [[ -z "$@" ]]; then
  echo "mingw-w64-build: error: missing ARCH option" >&2
  echo "See 'mingw-w64-build --help' for build options." >&2
  exit 1
fi

for arch in $@; do
  if [[ "$arch" != "i686" ]] && [[ "$arch" != "x86_64" ]]; then
    echo "mingw-w64-build: error: invalid ARCH: '$arch'" >&2
    exit 1
  fi
done

progs=(
  "wget"
  "gzip"
  "bzip2"
  "xz"
  "git"
  "make"
  "patch"
  "g++"
  "tr"
  "tar"
)
missing_progs=""
for prog in "${progs[@]}"; do
  if ! command -v $prog >/dev/null; then
    missing_progs="$prog $missing_progs"
  fi
done
if [[ -n "$missing_progs" ]]; then
  echo "mingw-w64-build: missing required program(s): $missing_progs" >&2
  exit 1
fi

cpus=$(grep -c processor /proc/cpuinfo 2>/dev/null || sysctl -n hw.ncpu | tr -d "\n" 2>/dev/null)
build=$(wget -qO - "http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD" | sh)
wd="$PWD"
src="$wd/src"
bld="$wd/bld"
log="$wd/bld/build.log"

rm -fr "$log" "$src" "$bld"
mkdir "$bld" "$src"
download_sources 3>&1 1>>"$log" 2>&1

for arch in $@; do
  build_toolchain "$arch" 3>&1 1>>"$log" 2>&1
done
rm -fr "$bld" "$src"

exit 0