#!/usr/bin/env bash
  
  # directory to download source files and store intermediates
  [[ -z $TARGET ]] && TARGET=i586-none-elf
  [[ -z $TMP_DIR ]] && TMP_DIR=/var/tmp/RIOT-toolchain-${USER}
  [[ -z $BUILDDIR ]] && BUILDDIR=${TMP_DIR}/${TARGET}
  [[ -z $PREFIX ]] && PREFIX=${PWD}/toolchain/${TARGET}
  [[ -z $MAKE_THREADS ]] && MAKE_THREADS=
  PATCHDIR=$(readlink -e "$(dirname $0)/patches")
  
  NEWLIB_VER=2.2.0.20150623
  NEWLIB_ARCHIVE=newlib-${NEWLIB_VER}.tar.gz
  NEWLIB_MD5=5cf6cd9ded91bca10c9f0a22a9da8e02
  NEWLIB_CONFIGURE_FLAGS=(
      --target=${TARGET}
      --prefix=${PREFIX}
      --with-gmp=${PREFIX}
      --with-mpfr=${PREFIX}
      --with-mpc=${PREFIX}
      --enable-interwork
      --enable-multilib
  
      --enable-target-optspace
      --disable-newlib-supplied-syscalls
      --disable-newlib-reent-small
      --enable-newlib-io-long-long
      --enable-newlib-io-float
      --enable-newlib-io-pos-args
      --enable-newlib-io-c99-formats
      --enable-newlib-multithread
  )
  NEWLIB_PATCHES=(
  newlib-2.2.0.20150623-RIOT-i586-none-elf.patch
  )
  NEWLIB_TARGET_CFLAGS=(
      -DREENTRANT_SYSCALLS_PROVIDED
      -DMALLOC_PROVIDED
      -DSIGNAL_PROVIDED
      -DPREFER_SIZE_OVER_SPEED
  
      -ggdb3
      -Os
      -fomit-frame-pointer
      -ffunction-sections
      -fdata-sections
  )
  
  GCC_VER=4.8.5
  GCC_ARCHIVE=gcc-${GCC_VER}.tar.bz2
  GCC_MD5=80d2c2982a3392bb0b89673ff136e223
  GCC_CONFIGURE_FLAGS=(
      --target=${TARGET}
      --prefix=${PREFIX}
      --with-gmp=${PREFIX}
      --with-mpfr=${PREFIX}
      --with-mpc=${PREFIX}
  
      --enable-interwork
      --enable-multilib
      --enable-languages="c,c++"
      --with-newlib
      --disable-libssp
      --with-headers=${BUILDDIR}/newlib-${NEWLIB_VER}/newlib/libc/include
      --enable-obsolete
      --enable-target-optspace
      --disable-nls
  )
  
  BINUTILS_VER=2.25
  BINUTILS_ARCHIVE=binutils-${BINUTILS_VER}.tar.bz2
  BINUTILS_MD5=d9f3303f802a5b6b0bb73a335ab89d66
  BINUTILS_CONFIGURE_FLAGS=(
      --prefix=${PREFIX}
  
      --enable-interwork
      --enable-multilib
      --disable-nls
  )
  
  GDB_VER=7.9.1
  GDB_ARCHIVE=gdb-${GDB_VER}.tar.xz
  GDB_MD5=35374c77a70884eb430c97061053a36e
  GDB_CONFIGURE_FLAGS=(
      --target=${TARGET}
      --prefix=${PREFIX}
      --with-gmp=${PREFIX}
      --with-mpfr=${PREFIX}
      --with-mpc=${PREFIX}
  
      --enable-interwork
      --enable-multilib
      --disable-nls
  )
  
  GMP_VER=5.1.3
  GMP_ARCHIVE=gmp-${GMP_VER}.tar.xz
  GMP_MD5=e5fe367801ff067b923d1e6a126448aa
  GMP_CONFIGURE_FLAGS=(
      --prefix=${PREFIX}
  
      --enable-cxx
      --disable-nls
  )
  
  MPFR_VER=3.1.2
  MPFR_ARCHIVE=mpfr-${MPFR_VER}.tar.xz
  MPFR_MD5=e3d203d188b8fe60bb6578dd3152e05c
  MPFR_CONFIGURE_FLAGS=(
      --prefix=${PREFIX}
      --with-gmp=${PREFIX}
  
      --disable-nls
  )
  
  MPC_VER=1.0.2
  MPC_ARCHIVE=mpc-${MPC_VER}.tar.gz
  MPC_MD5=68fadff3358fb3e7976c7a398a0af4c3
  MPC_CONFIGURE_FLAGS=(
      --prefix=${PREFIX}
      --with-gmp=${PREFIX}
      --with-mpfr=${PREFIX}
  
      --disable-nls
  )
  
  DOWNLOADER=wget
  DOWNLOADER_OPTS="-nv -c"
  
  SPACE_NEEDED=3264960
  
  build_binutils() {
      cd ${BUILDDIR}
      echo
      [[ -e .binutils_built ]] && return
  
      local TARGETS=(${TARGET} i386-efi-pe)
      for i in 0 1; do
          echo "Building binutils (${BINUTILS_VER}) for ${TARGETS[$i]} ..."
  
          rm -rf binutils-${TARGETS[$i]}-build &&
          mkdir -p binutils-${TARGETS[$i]}-build &&
          cd binutils-${TARGETS[$i]}-build &&
  
          ../binutils-${BINUTILS_VER}/configure "${BINUTILS_CONFIGURE_FLAGS[@]}" --target=${TARGETS[$i]} --enable-targets=${TARGETS[$i]},${TARGETS[1-$i]} &&
          make ${MAKE_THREADS} all &&
          make install &&
          cd ${BUILDDIR} ||
          return $?
      done
  
      date -uIns > .binutils_built
  }
  
  build_gcc() {
      cd ${BUILDDIR}
      echo
      echo "Building gcc (${GCC_VER}) ..."
      [[ -e .gcc_built ]] && return
  
      rm -rf gcc-build && mkdir -p gcc-build && cd gcc-build &&
      ../gcc-${GCC_VER}/configure "${GCC_CONFIGURE_FLAGS[@]}" &&
      make ${MAKE_THREADS} all &&
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .gcc_built
  }
  
  build_newlib() {
      cd ${BUILDDIR}
      echo
      echo "Building newlib (${NEWLIB_VER}) ..."
      [[ -e .newlib_built ]] && return
  
      rm -rf newlib-build && mkdir -p newlib-build && cd newlib-build &&
  
      CFLAGS="${NEWLIB_TARGET_CFLAGS[*]}" \
      CXXFLAGS="${NEWLIB_TARGET_CFLAGS[*]}" \
      CFLAGS_FOR_TARGET="${NEWLIB_TARGET_CFLAGS[*]}" \
      CXXFLAGS_FOR_TARGET="${NEWLIB_TARGET_CFLAGS[*]}" \
      ../newlib-${NEWLIB_VER}/configure "${NEWLIB_CONFIGURE_FLAGS[@]}" &&
      sed -i ./Makefile -e '/C\(XX\)\?FLAGS_FOR_TARGET = -g /d' &&
  
      make ${MAKE_THREADS} all &&
  
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .newlib_built
  }
  
  build_gdb() {
      cd ${BUILDDIR}
      echo
      echo "Building gdb (${GDB_VER}) ..."
      [[ -e .gdb_built ]] && return
  
      rm -rf gdb-build && mkdir -p gdb-build && cd gdb-build &&
      ../gdb-${GDB_VER}/configure "${GDB_CONFIGURE_FLAGS[@]}" &&
      make ${MAKE_THREADS} all CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0" &&
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .gdb_built
  }
  
  build_gmp() {
      cd ${BUILDDIR}
      echo
      echo "Building gmp (${GMP_VER}) ..."
      [[ -e .gmp_built ]] && return
  
      rm -rf gmp-build && mkdir -p gmp-build && cd gmp-build &&
      ../gmp-${GMP_VER}/configure "${GMP_CONFIGURE_FLAGS[@]}" &&
      make ${MAKE_THREADS} all &&
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .gmp_built
  }
  
  build_mpfr() {
      cd ${BUILDDIR}
      echo
      echo "Building mpfr (${MPFR_VER}) ..."
      [[ -e .mpfr_built ]] && return
  
      rm -rf mpfr-build && mkdir -p mpfr-build && cd mpfr-build &&
      ../mpfr-${MPFR_VER}/configure "${MPFR_CONFIGURE_FLAGS[@]}" &&
      make ${MAKE_THREADS} all &&
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .mpfr_built
  }
  
  build_mpc() {
      cd ${BUILDDIR}
      echo
      echo "Building mpc (${MPC_VER}) ..."
      [[ -e .mpc_built ]] && return
  
      rm -rf mpc-build && mkdir -p mpc-build && cd mpc-build &&
      ../mpc-${MPC_VER}/configure "${MPC_CONFIGURE_FLAGS[@]}" &&
      make ${MAKE_THREADS} all &&
      make install &&
  
      cd ${BUILDDIR} &&
      date -uIns > .mpc_built
  }
  
  clean() {
      echo
      echo "Cleaning up..."
      for F in binutils gcc newlib gdb gmp mpfr mpc; do
          rm -rf ./.${F}_extracted ./.${F}_built ./${F}_build || return $?
      done
  }
  
  export PATH=$PATH:${PREFIX}/bin
  
  download() {
      echo
      echo "Downloading TAR files."
  
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/binutils ${BINUTILS_ARCHIVE} ${BINUTILS_MD5} &&
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/gcc/gcc-${GCC_VER} ${GCC_ARCHIVE} ${GCC_MD5} &&
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/gdb ${GDB_ARCHIVE} ${GDB_MD5} &&
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/gmp ${GMP_ARCHIVE} ${GMP_MD5} &&
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/mpfr ${MPFR_ARCHIVE} ${MPFR_MD5} &&
      download_file ftp://ftp.cs.tu-berlin.de/pub/gnu/mpc ${MPC_ARCHIVE} ${MPC_MD5} &&
      download_file ftp://sources.redhat.com/pub/newlib ${NEWLIB_ARCHIVE} ${NEWLIB_MD5}
  }
  
  extract() {
      echo
      echo "Extracting TAR files."
  
      if [[ ! -x ./binutils-${BINUTILS_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${BINUTILS_ARCHIVE} || return $?
      fi
      if [[ ! -x ./gcc-${GCC_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${GCC_ARCHIVE} || return $?
      fi
      if [[ ! -x ./gdb-${GDB_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${GDB_ARCHIVE} || return $?
      fi
      if [[ ! -x ./gmp-${GMP_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${GMP_ARCHIVE} || return $?
      fi
      if [[ ! -x ./mpfr-${MPFR_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${MPFR_ARCHIVE} || return $?
      fi
      if [[ ! -x ./mpc-${MPC_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${MPC_ARCHIVE} || return $?
      fi
      if [[ ! -x ./newlib-${NEWLIB_VER}/configure ]]; then
          tar axf ${TMP_DIR}/${NEWLIB_ARCHIVE} &&
          for (( I=0; I < ${#NEWLIB_PATCHES[@]}; I+=1 )); do
              echo "Applying Newlib patch ${NEWLIB_PATCHES[$I]}"
              for (( P=0; P < 4; P+=1 )); do
                  patch -p${P} --ignore-whitespace --dry-run -f < "${PATCHDIR}/${NEWLIB_PATCHES[$I]}" 2>&1 > /dev/null || continue
                  patch -p${P} --ignore-whitespace -f < "${PATCHDIR}/${NEWLIB_PATCHES[$I]}" || return $?
                  break
              done
          done
      fi
  }
  
  download_file() {
      echo "Downloading ${1}/${2}..."
      cd ${TMP_DIR} &&
      ${DOWNLOADER} ${DOWNLOADER_OPTS} $1/$2 &&
      echo -n "Checking MD5 of " &&
      echo "${3}  ${2}" | md5sum -c - &&
      cd ${BUILDDIR}
  }
  
  check_space() {
      echo
      echo "Checking disk space in ${TMP_DIR}"
  
      FREETMP=$(df ${BUILDDIR} | awk '{ if (NR == 2) print $4}')
      if [[ $FREETMP -lt $SPACE_NEEDED ]]; then
          echo "Not enough available space in ${TMP_DIR}."
          echo "Minimum ${SPACE_NEEDED} free bytes required."
          return 1
      fi
  }
  
  all() {
      echo
      echo "Starting in ${BUILDDIR}. Installing to ${PREFIX}."
  
      check_space &&
      download &&
      extract &&
      build_binutils &&
      build_gmp &&
      build_mpfr &&
      build_mpc &&
      build_gcc &&
      build_newlib &&
      build_gdb &&
  
      echo &&
      echo 'Success!' &&
      echo "Insert \"export PATH=${PREFIX}/bin:\$PATH\" to your .bashrc"
  }
  
  usage() {
      echo "usage: ${0} [all | download | extract | clean | build_[binutils|gcc|newlib|gdb|gmp|mpfr|mpc]]"
      echo "example: ${0} all"
      echo ""
      echo "Builds a(n) \"${TARGET}\" toolchain,"
      echo "installs into \"${PREFIX}\", and"
      echo "uses \"${TMP_DIR}\" as temp."
      echo ""
      echo "Use PREFIX=... and TMP_DIR=... to change these directories."
      echo "Use TARGET=... to change the target (affects PREFIX)."
      echo ""
      echo "Run like \"MAKE_THREADS=-j$(nproc) ${0} all\" to speed up on multicore systems."
  }
  
  if [[ -z $1 ]]; then
      usage
      exit 1
  fi
  
  mkdir -p ${PREFIX} &&
  mkdir -p ${TMP_DIR} &&
  mkdir -p ${BUILDDIR} &&
  cd ${BUILDDIR} &&
  for arg; do
      ${arg} || exit $?
  done