dnl -*- Autoconf -*- fragment for the C++ daemon.

AC_ARG_ENABLE([daemon],
  [AS_HELP_STRING([--enable-daemon], [build the Nix daemon (C++)])],
  [guix_build_daemon="$enableval"],
  [guix_build_daemon="no"])

AC_MSG_CHECKING([whether to build daemon])
AC_MSG_RESULT([$guix_build_daemon])

dnl C++ environment.  This macro must be used unconditionnaly.
AC_PROG_CXX

if test "x$guix_build_daemon" = "xyes"; then

  AC_PROG_RANLIB
  AC_CONFIG_HEADER([nix/config.h])

  dnl Use 64-bit file system calls so that we can support files > 2 GiB.
  AC_SYS_LARGEFILE

  dnl Look for libbz2, a required dependency.
  AC_CHECK_LIB([bz2], [BZ2_bzWriteOpen], [true],
    [AC_MSG_ERROR([Guix requires libbz2, which is part of bzip2.  See http://www.bzip.org/.])])
  AC_CHECK_HEADERS([bzlib.h], [true],
    [AC_MSG_ERROR([Guix requires libbz2, which is part of bzip2.  See http://www.bzip.org/.])])

  dnl Look for SQLite, a required dependency.
  PKG_CHECK_MODULES([SQLITE3], [sqlite3 >= 3.6.19])

  AC_DEFINE([NIX_VERSION], ["0.0.0"], [Fake Nix version number.])
  AC_DEFINE_UNQUOTED([SYSTEM], ["$guix_system"],
    [Guix host system type--i.e., platform and OS kernel tuple.])

  case "$LIBGCRYPT_PREFIX" in
    no)
      LIBGCRYPT_CFLAGS=""
      LIBGCRYPT_LIBS=""
      ;;
    *)
      LIBGCRYPT_CFLAGS="-I$LIBGCRYPT_PREFIX/include"
      LIBGCRYPT_LIBS="-L$LIBGCRYPT_PREFIX/lib -lgcrypt"
      ;;
  esac
  AC_SUBST([LIBGCRYPT_CFLAGS])
  AC_SUBST([LIBGCRYPT_LIBS])

  save_CFLAGS="$CFLAGS"
  save_LDFLAGS="$LDFLAGS"
  CFLAGS="$CFLAGS $LIBGCRYPT_CFLAGS"
  LDFLAGS="$LDFLAGS $LIBGCRYPT_LDFLAGS"

  have_gcrypt=yes
  AC_CHECK_LIB([gcrypt], [gcry_md_open], [:], [have_gcrypt=no])
  AC_CHECK_HEADER([gcrypt.h], [:], [have_gcrypt=no])
  if test "x$have_gcrypt" != "xyes"; then
    AC_MSG_ERROR([GNU libgcrypt not found; please install it.])
  fi

  CFLAGS="$save_CFLAGS"
  LDFLAGS="$save_LDFLAGS"

  dnl Chroot support.
  AC_CHECK_FUNCS([chroot unshare])
  AC_CHECK_HEADERS([sched.h sys/param.h sys/mount.h])

  dnl Check for lutimes, optionally used for changing the mtime of
  dnl symlinks.
  AC_CHECK_FUNCS([lutimes])

  dnl Check whether the store optimiser can optimise symlinks.
  AC_MSG_CHECKING([whether it is possible to create a link to a symlink])
  ln -s bla tmp_link
  if ln tmp_link tmp_link2 2> /dev/null; then
      AC_MSG_RESULT(yes)
      AC_DEFINE(CAN_LINK_SYMLINK, 1, [Whether link() works on symlinks.])
  else
      AC_MSG_RESULT(no)
  fi
  rm -f tmp_link tmp_link2

  dnl Check for <locale>.
  AC_LANG_PUSH(C++)
  AC_CHECK_HEADERS([locale])
  AC_LANG_POP(C++)


  dnl Check whether we have the `personality' syscall, which allows us
  dnl to do i686-linux builds on x86_64-linux machines.
  AC_CHECK_HEADERS([sys/personality.h])

  dnl Check for <linux/fs.h> (for immutable file support).
  AC_CHECK_HEADERS([linux/fs.h])
fi

AM_CONDITIONAL([BUILD_DAEMON], [test "x$guix_build_daemon" = "xyes"])