#! /bin/sh
# pkg-config wrapper for cross-building
# Sets pkg-config search path to search multiarch and historical cross-compiling paths.

# If the user has already set PKG_CONFIG_LIBDIR, believe it (even if empty): 
# it's documented to be an override
if [ x"${PKG_CONFIG_LIBDIR+set}" = x ]; then
  # GNU triplet for the compiler, e.g. i486-linux-gnu for Debian i386,
  # i686-linux-gnu for Ubuntu i386
  basename="$(basename "$0")"
  triplet="${basename%-pkg-config}"
  # Normalized multiarch path if any, e.g. i386-linux-gnu for i386
  multiarch="$(dpkg-architecture -t"${triplet}" -qDEB_HOST_MULTIARCH 2>/dev/null)"
  if [ "$?" != 0 ]; then
      echo "Please install dpkg-dev to use pkg-config when cross-building" >&2
      exit 1
  fi
  # Native multiarch path
  native_multiarch="$(cat /usr/lib/pkg-config.multiarch)"

  # This can be used for native builds as well, in that case, just exec pkg-config "$@" directly.
  if [ "$native_multiarch" = "$multiarch" ]; then
     exec pkg-config "$@"
  fi

  PKG_CONFIG_LIBDIR="/usr/local/${triplet}/lib/pkgconfig"
  # For a native build we would also want to append /usr/local/lib/pkgconfig
  # at this point; but this is a cross-building script, so don't
  PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/local/share/pkgconfig"

  if [ -n "$multiarch" ]; then
    PKG_CONFIG_LIBDIR="/usr/local/lib/${multiarch}/pkgconfig:$PKG_CONFIG_LIBDIR"
    PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/lib/${multiarch}/pkgconfig"
  fi

  PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/${triplet}/lib/pkgconfig"
  # For a native build we would also want to append /usr/lib/pkgconfig
  # at this point; but this is a cross-building script, so don't
  # If you want to allow use of un-multiarched -dev packages for crossing 
  # (at the risk of finding build-arch stuff you didn't want, if not in a clean chroot)
  # Uncomment the next line:
  # PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/lib/pkgconfig"
  # ... but on Ubuntu we rely cross-building with non-multiarch libraries:
  if dpkg-vendor --derives-from Ubuntu; then
      PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/lib/pkgconfig"
  fi
  PKG_CONFIG_LIBDIR="$PKG_CONFIG_LIBDIR:/usr/share/pkgconfig"

  export PKG_CONFIG_LIBDIR
fi

exec pkg-config "$@"