gnunet/configure.ac

# This file is part of GNUnet.
# (C) 2001--2020 GNUnet e.V.
#
# GNUnet is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License,
# or (at your option) any later version.
#
# GNUnet 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
# Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# SPDX-License-Identifier: AGPL3.0-or-later
#
# Process this file with autoconf to produce a configure script.
#
#
AC_PREREQ(2.61)
# Checks for programs.
AC_INIT([gnunet], [0.13.3], [bug-gnunet@gnu.org])
AC_CONFIG_AUX_DIR([build-aux])

# check for legacy option that is no longer supported (#5627) and fail hard
AC_ARG_WITH(nssdir,
   [  --with-nssdir=DIR    legacy switch, no longer supported, do not use],
   [AC_MSG_RESULT([$with_nssdir])
    AS_CASE([$with_nssdir],
      [no],[],
      [AC_MSG_ERROR([--with-nssdir is no longer supported])])
   ])

AC_CANONICAL_TARGET
AC_CANONICAL_HOST
AC_CANONICAL_SYSTEM
AM_INIT_AUTOMAKE
m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])], [AM_DEFAULT_VERBOSITY=1 AC_SUBST(AM_DEFAULT_VERBOSITY)])
AC_CONFIG_HEADERS([gnunet_config.h])
AH_TOP([#define _GNU_SOURCE  1])
AC_CONFIG_MACRO_DIR([m4])
AC_PROG_AWK
AC_PROG_CC_C99
AC_PROG_OBJC
AC_PROG_INSTALL
AC_PROG_LN_S
AC_PROG_MAKE_SET
AM_PROG_CC_C_O
LT_INIT([disable-static dlopen])
AC_SUBST(MKDIR_P)

# allow for different autotools
AS_AUTOTOOLS_ALTERNATE

# large file support
AC_SYS_LARGEFILE
AC_FUNC_FSEEKO


CFLAGS="-Wall $CFLAGS"
AC_MSG_CHECKING(whether cc can use -fno-strict-aliasing)
# use '-fno-strict-aliasing', but only if the compiler can take it
AS_IF([$CC -fno-strict-aliasing -S -o /dev/null -xc /dev/null >/dev/null 2>&1],
 [CFLAGS="-fno-strict-aliasing $CFLAGS"])

# A helper which allows us to check cflags if compiler
AC_DEFUN([CC_CHECK_CFLAGS_SILENT], [
  AC_CACHE_VAL(AS_TR_SH([cc_cv_cflags_$1]),
    [ac_save_CFLAGS="$CFLAGS"
     CFLAGS="$CFLAGS $1 -Werror"
     AC_LINK_IFELSE([AC_LANG_SOURCE([int main() { return 0; }])],
       [eval "AS_TR_SH([cc_cv_cflags_$1])='yes'"],
       [eval "AS_TR_SH([cc_cv_cflags_$1])='no'"])
     CFLAGS="$ac_save_CFLAGS"
    ])

  AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
    [$2], [$3])
])


# CC_CHECK_CFLAG_APPEND(FLAG, [action-if-found], [action-if-not-found])
# Check for CFLAG and appends them to CFLAGS if supported
AC_DEFUN([CC_CHECK_CFLAG_APPEND], [
  AC_CACHE_CHECK([if $CC supports -Wno-$1 flag],
    AS_TR_SH([cc_cv_cflags_-W$1]),
    CC_CHECK_CFLAGS_SILENT([-W$1]) #gcc is stupid. It does not fail with the -W-no option for backwards compat but then shows the error "in case something goes wrong".
  )

  AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_-W$1])[ = xyes],
    [CFLAGS="$CFLAGS -Wno-$1"; $2], [$3])
])


# We make heavy use of this, llvm/gcc and gcc-9 give warnings so disable.
CC_CHECK_CFLAG_APPEND([address-of-packed-member])

# We make heavy use of this, llvm/gcc and gcc-9 give warnings so disable.
CC_CHECK_CFLAG_APPEND([tautological-constant-out-of-range-compare])

# Use Linux interface name unless the OS has a different preference
DEFAULT_INTERFACE="\"eth0\""

funcstocheck="getnameinfo gethostname gethostbyname gethostbyaddr getaddrinfo getaddrinfo_a"

# Srcdir in a form that native compiler understands (i.e. DOS path on W32)
native_srcdir=$srcdir

OLD_LDFLAGS="$LDFLAGS"
LDFLAGS="$LDFLAGS -Wl,--unresolved-symbols=report-all"

# Check system type
AS_CASE(["$host_os"],
  [*darwin* | *rhapsody* | *macosx*],[
     AC_DEFINE_UNQUOTED(DARWIN,1,[This is an Apple Darwin system])
     CPPFLAGS="-D_APPLE_C_SOURCE $CPPFLAGS"
     CFLAGS="-fno-common $CFLAGS"
     LDFLAGS="$OLD_LDFLAGS"
     AC_MSG_WARN([WARNING: The VPN application cannot be compiled on your OS])
     AC_CHECK_LIB(intl, gettext)
     build_target="darwin"
     DEFAULT_INTERFACE="\"en0\""
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [linux*],[
     AC_DEFINE_UNQUOTED(LINUX,1,[This is a Linux kernel])
     build_target="linux"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
     AC_PATH_XTRA
  ],
  [*freebsd*],[
     CFLAGS="-D_THREAD_SAFE $CFLAGS"
     build_target="freebsd"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [*openbsd*],[
     # We need to explicitly link libc
     LDFLAGS="$LDFLAGS -Wl,-lc"
     # We also need to enable PIC
     CFLAGS="-fPIC $CFLAGS"
     build_target="openbsd"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [*netbsd*],[
     build_target="netbsd"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [*solaris*],[
     AC_DEFINE_UNQUOTED(SOLARIS,1,[This is a Solaris system])
     AC_DEFINE_UNQUOTED(_REENTRANT,1,[Need with solaris or errno doesnt work])
     AC_CHECK_LIB(resolv, res_init)
     AC_CHECK_LIB(rt, nanosleep)
     build_target="solaris"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [*arm-linux*],[
     AC_DEFINE_UNQUOTED(LINUX,1,[This is a Linux kernel])
     CFLAGS="-D_REENTRANT -fPIC -pipe $CFLAGS"
     build_target="linux"
     LIBPREFIX=
     DLLDIR=lib
     UNIXONLY="#"
  ],
  [gnu*],[
     AC_DEFINE_UNQUOTED(GNU,1,[This is a GNU system])
     build_target="gnu"
     UNIXONLY="#"
  ],
  [
     AC_MSG_RESULT(Unrecognised OS $host_os)
     AC_DEFINE_UNQUOTED(OTHEROS,1,[Some strange OS])
     UNIXONLY=""
])
AC_DEFINE_UNQUOTED([GNUNET_DEFAULT_INTERFACE], $DEFAULT_INTERFACE, [This should be the default choice for the name of the first network interface])
AC_SUBST(DEFAULT_INTERFACE)

# Disable TCP-based IPC on systems that support UNIX domain
# sockets in default configuratin:
AC_SUBST(UNIXONLY)


AC_MSG_CHECKING([for build target])
AM_CONDITIONAL(DARWIN,  test "$build_target" = "darwin")
AM_CONDITIONAL(SOLARIS, test "$build_target" = "solaris")
AM_CONDITIONAL(XNETBSD, test "$build_target" = "netbsd")
AM_CONDITIONAL(XFREEBSD, test "$build_target" = "freebsd")
AM_CONDITIONAL(OPENBSD, test "$build_target" = "openbsd")
# FIXME: We need a define BSD for some binaries like we
# need define LINUX for some. This does not scale, how
# can we solve this better?
AM_CONDITIONAL(XBSD, test "$build_target" = "netbsd" -o "$build_target" = "freebsd" -o "$build_target" = "openbsd")
AM_CONDITIONAL(LINUX, test "$build_target" = "linux")
AM_CONDITIONAL(GNU, test "$build_target" = "gnu")

AC_MSG_RESULT([$build_target])
AC_SUBST(build_target)
AM_CONDITIONAL([am__fastdepOBJC], false)
AC_UNALIGNED_64_ACCESS

# some other checks for standard libs
AC_SEARCH_LIBS([gethostbyname], [nsl ws2_32])
AC_SEARCH_LIBS([memrchr], [],
               AC_DEFINE(HAVE_MEMRCHR,1,[memrchr supported]), [])
AC_SEARCH_LIBS([memset_s], [],
               AC_DEFINE(HAVE_MEMSET_S,1,[memset_s supported]), [])
AC_SEARCH_LIBS([explicit_bzero], [],
               AC_DEFINE(HAVE_EXPLICIT_BZERO,1,[explicit_bzero supported]), [])
AC_CHECK_LIB(socket, socket)
AC_CHECK_LIB(m, log)
AC_CHECK_LIB(c, getloadavg, AC_DEFINE(HAVE_GETLOADAVG,1,[getloadavg supported]))

AC_CHECK_PROG(VAR_GETOPT_BINARY, getopt, true, false)
AM_CONDITIONAL(HAVE_GETOPT_BINARY, $VAR_GETOPT_BINARY)

AC_CHECK_PROGS(PKG_CONFIG, [pkgconf, pkg-config], false)
AM_CONDITIONAL(HAVE_PKG_CONFIG, test x$PKG_CONFIG != xfalse)

AC_CHECK_PROG(VAR_SSH_BINARY, ssh, true, false)
AM_CONDITIONAL(HAVE_SSH_BINARY, $VAR_SSH_BINARY)
AC_MSG_CHECKING(for SSH key)
  AM_CONDITIONAL(HAVE_SSH_KEY,  ssh -D 12345 -o "BatchMode yes" -o "UserKnownHostsFile /tmp/gnunet_test_cosks_ssh_garbage" -o "StrictHostKeyChecking no" 127.0.0.1 echo -n)
  if test -f /tmp/gnunet_test_cosks_ssh_garbage; then
     rm -f /tmp/gnunet_test_cosks_ssh_garbage
  fi


# autotools' m4 for python has no maximum version!
# python3.4 - python3.8 for tests (3.8 unchecked)
# TODO: document how to override the lowest version
# TODO: found by this.
m4_define_default([_AM_PYTHON_INTERPRETER_LIST],[python3 python3.4 python3.5 python3.6 python3.7 python3.8 python])
AM_PATH_PYTHON([3.4],, [:])
AC_SUBST([PYTHON])
AM_CONDITIONAL([HAVE_PYTHON], [test "$PYTHON" != :])


# perl
AC_PATH_PROG( PERL, perl, ,
              $PATH:/usr/local/bin/perl:/usr/bin/:/usr/local/bin )
AC_SUBST([PERL])
AM_CONDITIONAL([HAVE_PERL], [test -x "$PERL"])
AS_IF([test -x "$PERL"],
  [AC_DEFINE_UNQUOTED([HAVE_PERL], [1], [Path to Perl])],
  [AC_DEFINE_UNQUOTED([HAVE_PERL], [0], [Path to Perl])])

# awk
AC_PATH_PROGS( AWK_BINARY, [awk gawk], ,$PATH:/usr/bin/:/usr/local/bin )
AC_SUBST([AWK_BINARY])
AM_CONDITIONAL([HAVE_AWK], [test -x "$AWK_BINARY"])
AS_IF([test -x "$AWK_BINARY"],
  [AC_DEFINE_UNQUOTED([HAVE_AWK], [1], [Path to awk])],
  [AC_DEFINE_UNQUOTED([HAVE_AWK], [0], [Path to awk])])

# should we install gnunet-logread?
AC_MSG_CHECKING(whether to install gnunet-logread)
AC_ARG_WITH([gnunet-logread],
              [AS_HELP_STRING([--with-gnunet-logread],
                              [Install gnunet-logread])],
              [logread=${withval}],
              [logread=no])
AC_MSG_RESULT($logread)
AS_IF([test "x$logread" = "xyes"],
      [AM_CONDITIONAL([GNUNET_LOGREAD], true)
       AC_DEFINE([GNUNET_LOGREAD],
                 [1],
                 [Installing gnunet-logread])],
      [AM_CONDITIONAL([GNUNET_LOGREAD],
                      false)
       AC_DEFINE([GNUNET_LOGREAD],
                 [0],
                 [Not installing gnunet-logread])])

# iptables is a soft requirement to run tests
AC_PATH_TARGET_TOOL(VAR_IPTABLES_BINARY, iptables, false)

AS_IF([test x"$VAR_IPTABLES_BINARY" = x"false"],
 [AS_IF([test -x "/sbin/iptables"],
   [VAR_IPTABLES_BINARY="/sbin/iptables"],
   [AS_IF([test -x "/usr/sbin/iptables"],
      [VAR_IPTABLES_BINARY="/usr/sbin/iptables"])])])

AS_IF([test x"$VAR_IPTABLES_BINARY" != x"false"],
 [AC_DEFINE_UNQUOTED([IPTABLES], "$VAR_IPTABLES_BINARY", [Path to iptables])],
 [AC_MSG_WARN([warning: 'iptables' not found.])])

# ip6tables is a soft requirement for some features
AC_PATH_TARGET_TOOL(VAR_IP6TABLES_BINARY, ip6tables, false)

AS_IF([test x"$VAR_IP6TABLES_BINARY" = x"false"],
  [AS_IF([test -x "/sbin/ip6tables"],
     [VAR_IP6TABLES_BINARY="/sbin/ip6tables"],
     [AS_IF([test -x "/usr/sbin/ip6tables"],
        [VAR_IP6TABLES_BINARY="/usr/sbin/ip6tables"])])])


AS_IF([test x"$VAR_IP6TABLES_BINARY" != x"false"],
  [AC_DEFINE_UNQUOTED([IP6TABLES], "$VAR_IP6TABLES_BINARY", [Path to ip6tables])],
  [AC_MSG_WARN([warning: 'ip6tables' not found.])])

# ip is a soft requirement for some features
AC_PATH_TARGET_TOOL(VAR_IP_BINARY, ip, false)

AS_IF([test x"$VAR_IP_BINARY" = x"false"],
 [AS_IF([test -x "/sbin/ip"],
   [VAR_IP_BINARY="/sbin/ip"],
   [AS_IF([test -x "/usr/sbin/ip"],
          [VAR_IP_BINARY="/usr/sbin/ip"])])])

AS_IF([test x"$VAR_IP_BINARY" != x"false"],
 [AC_DEFINE_UNQUOTED([PATH_TO_IP], "$VAR_IP_BINARY", [Path to ip])],
 [AC_MSG_WARN([warning: 'ip' not found.])])

# locate 'ifconfig'
AC_PATH_TARGET_TOOL(VAR_IFCONFIG_BINARY, ifconfig, false)

AC_CHECK_PROG(VAR_IFCONFIG_BINARY, ifconfig, true, false)
AS_IF([test x"$VAR_IFCONFIG_BINARY" = x"false"],
  [AS_IF([test -x "/sbin/ifconfig"],
     [VAR_IFCONFIG_BINARY="/sbin/ifconfig"],
     [AS_IF([test -x "/usr/sbin/ifconfig"],
            [VAR_IFCONFIG_BINARY="/usr/sbin/ifconfig"])])])

AS_IF([test x"$VAR_IFCONFIG_BINARY" != x"false"],
  [AC_DEFINE_UNQUOTED([IFCONFIG], "$VAR_IFCONFIG_BINARY", [Path to ifconfig])],
  [AC_MSG_WARN(['ifconfig' not found.])])


# Test if 'adduser' binary exists
MSG_USER_SETUP=true
AC_PATH_PROG([MSG_USER_SETUP],
  [adduser],
  false,
  [path=$PATH$PATH_SEPARATOR/usr/sbin$PATH_SEPARATOR/sbin])

# Test if 'gnunet' user and the groups exist
getent passwd gnunet > /dev/null
HAVE_GNUNET_USER=$?
getent group gnunet > /dev/null
AS_IF([test x$? != x0],
      [HAVE_GNUNET_USER=1])
getent group gnunetdns > /dev/null
AS_IF([test x$? != x0],
      [HAVE_GNUNET_USER=1])

AC_PATH_TARGET_TOOL(VAR_SYSCTL_BINARY, sysctl, false)

AC_CHECK_PROG(VAR_SYSCTL_BINARY, sysctl, true, false)
AS_IF([test x"$VAR_SYSCTL_BINARY" = x"false"],
      [AS_IF([test -x "/sbin/sysctl"],
             [VAR_SYSCTL_BINARY="/sbin/sysctl"],
             [AS_IF([test -x "/usr/sbin/sysctl"],
                    [VAR_SYSCTL_BINARY="/usr/sbin/sysctl"])])])
AS_IF([test x"$VAR_SYSCTL_BINARY" != x"false"],
      [AC_DEFINE_UNQUOTED([SYSCTL], "$VAR_SYSCTL_BINARY", [Path to sysctl])],
      [AC_MSG_WARN(['sysctl' not found.])])

# miniupnpc / upnpc binary is a soft runtime requirement
AC_PATH_TARGET_TOOL(VAR_UPNPC_BINARY, upnpc, false)

AS_IF([test x"$VAR_UPNPC_BINARY" != x"false"],
  [AC_DEFINE_UNQUOTED([UPNPC], "$VAR_UPNPC_BINARY", [Path to upnpc binary])],
  [AC_MSG_WARN([warning: 'upnpc' binary not found.])])


# checkbashisms
AC_CHECK_PROGS(CHECKBASHISMS_BINARY, [checkbashisms checkbashisms.pl], false)
AM_CONDITIONAL(HAVE_CHECKBASHISMS, test x$CHECKBASHISMS_BINARY != xfalse)

# uncrustify
# TODO: maybe add flag to pass location
AC_CHECK_PROG(UNCRUSTIFY_BINARY, uncrustify, true)
AM_CONDITIONAL(HAVE_UNCRUSTIFY_BINARY, $UNCRUSTIFY_BINARY)

# yapf
# TODO: less repetition, add flag to pass name
AC_CHECK_PROGS(YAPF_BINARY, [yapf yapf3.0 yapf3.1 yapf3.2 yapf3.3 yapf3.4 yapf3.5 yapf3.6 yapf3.7 yapf3.8 yapf3.9 yapf4.0], false)
AM_CONDITIONAL(HAVE_YAPF_BINARY, test x$YAPF_BINARY != xfalse)


AC_CHECK_MEMBER(struct tm.tm_gmtoff,
  [AC_DEFINE(HAVE_TM_GMTOFF, 1,
     [Define if struct tm has the tm_gmtoff member.])],
     ,
     [#include <time.h>])

# 'save' libs; only those libs found so far will be
# linked against _everywhere_.  For the others, we
# will be more selective!
SAVE_LIBS=$LIBS

have_addrinfo_a=0
AC_CHECK_LIB(anl,
             getaddrinfo_a,
             [have_addrinfo_a=1 AC_DEFINE(HAVE_GETADDRINFO_A,
                                          1,
                                          [getaddrinfo_a supported])])
AM_CONDITIONAL(HAVE_GETADDRINFO_A,
               [test "$have_addrinfo_a" = 1])

# libgcrypt
gcrypt=0
NEED_LIBGCRYPT_API=1
NEED_LIBGCRYPT_VERSION=1.6.0


AM_PATH_LIBGCRYPT("$NEED_LIBGCRYPT_API:$NEED_LIBGCRYPT_VERSION", gcrypt=1)
AC_CHECK_DECLS([gcry_mpi_set_opaque_copy], [], [], [[#include <gcrypt.h>]])

AS_IF([test $gcrypt = 0],
 [
  AC_MSG_ERROR([[
***
*** You need libgcrypt to build this program.
*** This library is for example available at
*** ftp://ftp.gnupg.org/gcrypt/libgcrypt/.
*** At least version $NEED_LIBGCRYPT_VERSION (API $NEED_LIBGCRYPT_API)
***  is required.
***]])
])
AC_DEFINE_UNQUOTED([NEED_LIBGCRYPT_VERSION], "$NEED_LIBGCRYPT_VERSION", [required libgcrypt version])

AC_CHECK_DECLS([struct in6_ifreq], [], [], [[#include <linux/if_tun.h>]])

AC_CHECK_HEADER([if_tun.h],
    [AC_DEFINE([IF_TUN_HDR], ["if_tun.h"], [if_tun.h include path])],
    [AC_CHECK_HEADER([linux/if_tun.h],
        [AC_DEFINE([IF_TUN_HDR], ["linux/if_tun.h"])],
        [AC_CHECK_HEADER([net/if_tun.h],
            [AC_DEFINE([IF_TUN_HDR], ["net/if_tun.h"])],
            [AC_CHECK_HEADER([net/tun/if_tun.h],
                [AC_DEFINE([IF_TUN_HDR], ["net/tun/if_tun.h"])])])])])


# should the build process be building the documentation?
AC_MSG_CHECKING(whether to build documentation)
AC_ARG_ENABLE([documentation],
              [AS_HELP_STRING([--disable-documentation],
                              [do not build the documentation])],
              [documentation=${enableval}],
              [documentation=yes])
AC_MSG_RESULT($documentation)
AS_IF([test "x$documentation" = "xyes"],
      [AM_CONDITIONAL([DOCUMENTATION],
                      true)
       AC_DEFINE([DOCUMENTATION],
                 [1],
                 [Building the documentation])],
      [AM_CONDITIONAL([DOCUMENTATION],
                      false)
       AC_DEFINE([DOCUMENTATION],
                 [0],
                 [Not building the documentation])])

# COMMENT: Check whether to transpile texinfo to mdoc.
# COMMENT: This is TRUE when --enable-texi2mdoc-generation
# COMMENT: but ERRORS when texi2mdoc binary is missing in your $PATH
# COMMENT: and makes the configure fail if it is missing.
# COMMENT: Consequential the DEFINE and CONDITIONAL are set to true.
# COMMENT: This is FALSE when --disable-texi2mdoc-generation was set
# COMMENT: or nothing was set (this is the default).
# COMMENT: There are 2 nested AS_IFs because we need to catch the
# COMMENT: potential non-existence of the texi2mdoc binary.
# COMMENT: Default return value / setting: no
AC_MSG_CHECKING(whether to include generated texi2mdoc output in installation)
AC_ARG_ENABLE([texi2mdoc-generation],
              [AS_HELP_STRING([--enable-texi2mdoc-generation],
                              [include generated texi2mdoc output in installation])],
              [texi2mdoc_generation=${enableval}],
              [texi2mdoc_generation=no])
AC_MSG_RESULT($texi2mdoc_generation)
AS_IF([test "x$texi2mdoc_generation" = "xyes"],
      [AS_IF([test "$texi2mdoc" = 0],
             [AC_MSG_WARN([ERROR: transpiled mdoc output requires texi2mdoc.])
              AC_MSG_WARN([ERROR: texi2mdoc can be obtained via your])
              AC_MSG_WARN([ERROR: Operating System package manager or from])
              AC_MSG_WARN([ERROR: https://mandoc.bsd.lv/texi2mdoc/])],
             [AM_CONDITIONAL([TEXI2MDOC_GENERATION],true)
              AC_DEFINE([TEXI2MDOC_GENERATION],
                        [1],
                        [Building section 7 mdoc output])])],
      [AM_CONDITIONAL([TEXI2MDOC_GENERATION],
                      false)
       AC_DEFINE([TEXI2MDOC_GENERATION],
                 [0],
                 [Not building section 7 mdoc output])])

# test for texi2mdoc (the binary, not the script distributed
# with autogen)
# TODO: refactor this and the check above.
AC_MSG_CHECKING(for texi2mdoc binary)
AC_CHECK_PROGS(TEXI2MDOC_BINARY, [texi2mdoc], false)
AM_CONDITIONAL(HAVE_TEXI2MDOC, test x$TEXI2MDOC_BINARY != xfalse)

# texi2man is a tool which needs to be investigated and
# is probably incompatible to texi2mdoc in invocation.
# Detection at this point only serves as a reminder that
# I will work this into the build-system.
AC_MSG_CHECKING(for texi2man perl script)
AC_CHECK_PROGS(TEXI2MAN_SCRIPT, [texi2man], false)
AM_CONDITIONAL(HAVE_TEXI2MAN, test x$TEXI2MAN_SCRIPT != xfalse)


# test for mandoc
AC_MSG_CHECKING(for mandoc binary)
AC_CHECK_PROGS(MANDOC_BINARY, [mandoc], false)
AM_CONDITIONAL(HAVE_MANDOC, test x$MANDOC_BINARY != xfalse)

# should the build process be building only the documentation?
AC_MSG_CHECKING(whether to build only documentation)
AC_ARG_ENABLE([documentation-only],
   [AS_HELP_STRING([--enable-documentation-only],
                   [build only the documentation])],
   [documentation_only=${enableval}],
   [documentation_only=no])
AC_MSG_RESULT($documentation_only)
AS_IF([test "x$documentation_only" = "xyes"],
 [
  AM_CONDITIONAL([DOCUMENTATION_ONLY],true)
  AC_DEFINE([DOCUMENTATION_ONLY],[1],[Building only the documentation])
 ],[
  AM_CONDITIONAL([DOCUMENTATION_ONLY],false)
  AC_DEFINE([DOCUMENTATION_ONLY],[0],[Doing a normal build, more than only documentation])
 ])

# should the build process be including the manpages? (default: yes)
AC_MSG_CHECKING(whether to include man pages)
AC_ARG_ENABLE([include-manpages],
   [AS_HELP_STRING([--disable-include-manpages],
                   [Do not include the man pages in build and installation])],
   [include_manpages=${enableval}],
   [include_manpages=yes])
AC_MSG_RESULT($include_manpages)
AS_IF([test "x$include_manpages" = "xyes"],
 [
  AM_CONDITIONAL([INCLUDE_MANPAGES],true)
  AC_DEFINE([INCLUDE_MANPAGES],[1],[Including the man pages in the build and installation])
 ],[
  AM_CONDITIONAL([INCLUDE_MANPAGES],false)
  AC_DEFINE([INCLUDE_MANPAGES],[0],[Not including the man pages in the build and installation])
 ])

# Do we have texinfo4? If yes, it is used to set texinfo4 specific switches
# (not syntax!) to the commandline tools which generate the html. If not,
# texinfo5 switches are used. This comes with no version checks, is
# enabled only at distributors action (ie defaults to "no").
# Mantis #3914 for more details (https://bugs.gnunet.org/view.php?id=3914)
AC_MSG_CHECKING(whether to enable texinfo4 switches)
AC_ARG_ENABLE([texinfo4],
   [AS_HELP_STRING([--enable-texinfo4], [Use texinfo version 4 specific switches])],
   [activate_texinfo4=${enableval}],
   [activate_texinfo4=no])
AC_MSG_RESULT($activate_texinfo4)
AS_IF([test "x$activate_texinfo4" = "xyes"],
 [
  AM_CONDITIONAL([ACTIVATE_TEXINFO4],true)
  AC_DEFINE([ACTIVATE_TEXINFO4],[1],[Using texinfo version 4 specific switches])
 ],[
  AM_CONDITIONAL([ACTIVATE_TEXINFO4],false)
  AC_DEFINE([INCLUDE_MANPAGES],[0],[Using texinfo version 5 or later switches])
 ])


# Adam shostack suggests the following for Windows:
# -D_FORTIFY_SOURCE=2 -fstack-protector-all
AC_ARG_ENABLE([gcc-hardening],
   AS_HELP_STRING(--enable-gcc-hardening, enable compiler security checks),
[AS_IF([test x$enableval = xyes],[
    CFLAGS="$CFLAGS -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fstack-protector-all"
    CFLAGS="$CFLAGS -fwrapv -fPIE -Wstack-protector"
    CFLAGS="$CFLAGS --param ssp-buffer-size=1"
    LDFLAGS="$LDFLAGS -pie"
 ])])

# Linker hardening options
# Currently these options are ELF specific - you can't use this with MacOSX
AC_ARG_ENABLE([linker-hardening],
  AS_HELP_STRING(--enable-linker-hardening, enable linker security fixups),
[AS_IF([test x$enableval = xyes],
   [LDFLAGS="$LDFLAGS -z relro -z now"])])


AC_ARG_ENABLE([sanitizer],
  AS_HELP_STRING(--enable-sanitizer, enable Address Sanitizer and Undefined Behavior Sanitizer),
[AS_IF([test x$enableval = xyes],[
   LDFLAGS="$CFLAGS -fsanitize=address,undefined -fno-omit-frame-pointer"
 ])])


extra_logging=GNUNET_NO
AC_ARG_ENABLE([logging],
   AS_HELP_STRING([--enable-logging@<:@=value@:>@],[Enable logging calls. Possible values: yes,no,verbose,veryverbose ('yes' is the default)]),
   [AS_IF([test "x$enableval" = "xyes"], [],
          [test "x$enableval" = "xno"], [AC_DEFINE([GNUNET_CULL_LOGGING],[],[Define to cull all logging calls])],
          [test "x$enableval" = "xverbose"], [extra_logging=GNUNET_YES]
          [test "x$enableval" = "xveryverbose"], [extra_logging=\(GNUNET_YES+1\)])
   ], [])
AC_DEFINE_UNQUOTED([GNUNET_EXTRA_LOGGING],[$extra_logging],[1 if extra logging is enabled, 2 for very verbose extra logging, 0 otherwise])

# should memory poisoning be enabled?
AC_MSG_CHECKING(whether to poison freed memory)
AC_ARG_ENABLE([poisoning],
   [AS_HELP_STRING([--enable-poisoning], [enable poisoning of freed memory (good for debugging)])],
   [enable_poisoning=${enableval}],
   [
     AS_IF([test "x$extra_logging" != "xGNUNET_NO"],
       [enable_poisoning="defaults to yes (extra logging is enabled)"],
       [enable_poisoning=no])
   ])
AC_MSG_RESULT($enable_poisoning)
AS_IF([test ! "x$enable_poisoning" = "xno"],
  [enable_poisoning=1],
  [enable_poisoning=0])
AC_DEFINE_UNQUOTED([ENABLE_POISONING],[$enable_poisoning],[1 if freed memory should be poisoned, 0 otherwise])

AS_IF([test $build = $target],
[
AC_MSG_CHECKING([for working HMAC])
AC_LANG_PUSH(C)
LIBS="$LIBS $LIBGCRYPT_LIBS"
CFLAGS="$CFLAGS $LIBGCRYPT_CFLAGS"
AC_RUN_IFELSE(
  [AC_LANG_PROGRAM([#include <gcrypt.h>
  	#include <stdio.h>], [[
        gcry_md_hd_t mac;

        unsigned char data[] = { 0xbf, 0x16, 0x6e, 0x46, 0x3a, 0x6c, 0xf3, 0x93, 0xa7, 0x72,
            0x11, 0xa1, 0xdc, 0x0b, 0x07, 0xdb, 0x1a, 0x5e, 0xd9, 0xb9, 0x81, 0xbe,
            0xea, 0xe4, 0x31, 0x5f, 0x24, 0xff, 0xfe, 0x50, 0x8a, 0xde };
        unsigned char key[] = { 0xfc, 0x62, 0x76, 0x35 };
        unsigned char result[] = {0xa2, 0xb, 0x1, 0xd9, 0xc0, 0x8b, 0x5a, 0x12, 0x80,
            0xd5, 0x50, 0x12, 0x8e, 0xd0, 0x5b, 0xb6, 0x5c, 0x87, 0x24, 0xe2, 0xd0,
            0xd2, 0xaf, 0x63, 0xae, 0xd1, 0xd6, 0x64, 0x14, 0xe3, 0x6e, 0x61, 0x5b,
            0xd, 0xba, 0x17, 0x7d, 0xd3, 0x10, 0xb1, 0x37, 0x41, 0x91, 0x7d, 0xeb,
            0x1, 0x4d, 0x71, 0xe8, 0x59, 0x71, 0x42, 0x8e, 0xd6, 0xf3, 0x29, 0x3b,
            0x90, 0xf2, 0xd1, 0xaf, 0x65, 0x1e, 0xb3};

        if (!gcry_check_version (GCRYPT_VERSION))
        {
          fprintf (stderr, "Version mismatch %s <-> %s \n", gcry_check_version (NULL), GCRYPT_VERSION);
          return 1;
        }

        gcry_control (GCRYCTL_DISABLE_SECMEM, 0);
        gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);

        if (gcry_md_open(&mac, GCRY_MD_SHA512, GCRY_MD_FLAG_HMAC) != GPG_ERR_NO_ERROR)
        {
          fprintf (stderr, "gcry_md_open error\n");
          return 2;
        }

        gcry_md_setkey (mac, key, sizeof (key));
        gcry_md_write (mac, data, sizeof (data));

        if (memcmp(gcry_md_read (mac, 0), result, gcry_md_get_algo_dlen (gcry_md_get_algo (mac))) != 0)
        {
          fprintf (stderr, "memcmp error\n");
          return 3;
        }

        gcry_md_close (mac);

        return 0;
    ]])],
  [AC_MSG_RESULT([yes])],
  [
   RESULT=$?
   if test $RESULT = 3
   then
     AC_MSG_FAILURE([HMAC test vector does not match. This is a known problem with libgcrypt 1.2.2 on Windows and fixed in 1.4.6.])
   fi
   if test $RESULT = 2
   then
     AC_MSG_FAILURE([HMAC test failed])
   fi
   if test $RESULT = 1
   then
     AC_MSG_FAILURE([libgcrypt header version does not match library version])
   fi
  ],
  [AC_MSG_RESULT([cross compiling, test skipped])])
AC_LANG_POP(C)
])	# $build = $target

AC_COMPILE_IFELSE([AC_LANG_SOURCE(
  [[int main() {
      _Static_assert(sizeof(int) >= 4, "not big enough");
      return 0;
    };]])],
  [AC_DEFINE([HAVE_STATIC_ASSERT],[1],[Static assertions supported])],
  [AC_DEFINE([HAVE_STATIC_ASSERT],[0],[Static assertions not supported])])

# check for bluetooth library
bluetooth=0
AC_MSG_CHECKING(for libbluetooth)
AC_ARG_WITH(libbluetooth,
    [  --with-libbluetooth=PREFIX (base of libbluetooth installation)],
    [AC_MSG_RESULT([$with_libbluetooth])
     AS_CASE([$with_libbluetooth],
        [no],[],
        [yes],[
            CHECK_LIBHEADER(BLUETOOTH,
                            bluetooth,
                            ba2str,
                            bluetooth/bluetooth.h,
                            bluetooth=1,)
        ],[
            LDFLAGS="-L$with_libbluetooth/lib $LDFLAGS"
            CPPFLAGS="-I$with_libbluetooth/include $CPPFLAGS"
            AC_CHECK_HEADERS(bluetooth/bluetooth.h,
                             AC_CHECK_LIB([bluetooth],
                                          [ba2str],
                                          EXT_LIB_PATH="-L$with_libbluetooth/lib $EXT_LIB_PATH"
                                          bluetooth=1))
        ])
    ],
    [AC_MSG_RESULT([--with-libbluetooth not specified])
     CHECK_LIBHEADER(BLUETOOTH,
                     bluetooth,
                     ba2str,
                     bluetooth/bluetooth.h,
                     bluetooth=1,)])
AM_CONDITIONAL(HAVE_LIBBLUETOOTH, [test "$bluetooth" = 1])
AS_IF([test "$bluetooth" = 1],
      [AC_DEFINE([HAVE_LIBBLUETOOTH],[1],[Have bluetooth library])],
      [AC_DEFINE([HAVE_LIBBLUETOOTH],[0],[Lacking bluetooth library])])

# check for zbar library
# NOTE: Do not add checks for: -lSM, -lICE, -lX11, -lXv and -ljpeg
# NOTE: they must be provided by the build environment, not the
# NOTE: build-system of gnunet, as they are 2nd or 3rd level dependencies.
zbar=0
AC_MSG_CHECKING(for libzbar)
AC_ARG_WITH(zbar,
   [  --with-zbar=PREFIX (base of libzbar installation)],
   [AC_MSG_RESULT([$with_zbar])
    AS_CASE([$with_zbar],
      [no],[],
      [yes],[CHECK_LIBHEADER(ZBAR, zbar, zbar_processor_create, zbar.h,zbar=1,,)],
      [
        LDFLAGS="-L$with_zbar/lib $LDFLAGS"
        CPPFLAGS="-I$with_zbar/include $CPPFLAGS"
        AC_CHECK_HEADERS(zbar.h,
          AC_CHECK_LIB([zbar], [zbar_processor_create],
            EXT_LIB_PATH="-L$with_zbar/lib $EXT_LIB_PATH"
            zbar=1))
       ])
   ],
   [AC_MSG_RESULT([--with-zbar not specified])
    CHECK_LIBHEADER(ZBAR, zbar, zbar_processor_create, zbar.h,zbar=1,,)])
AM_CONDITIONAL(HAVE_ZBAR, [test "$zbar" = 1])
AS_IF([test "x$zbar" = x1],
      [AC_DEFINE([HAVE_ZBAR],[1],[Have zbar library])],
      [AC_DEFINE([HAVE_ZBAR],[0],[Lacking zbar library])])

# check for jansson library
jansson=0
AC_MSG_CHECKING(for libjansson)
AC_ARG_WITH(jansson,
   [  --with-jansson=PREFIX (base of libjansson installation)],
   [AC_MSG_RESULT([$with_jansson])
    AS_CASE([$with_jansson],
      [no],[],
      [yes],[
        CHECK_LIBHEADER(JANSSON, jansson, json_loads, jansson.h,jansson=1,)
      ],[
        LDFLAGS="-L$with_jansson/lib $LDFLAGS"
        CPPFLAGS="-I$with_jansson/include $CPPFLAGS"
        AC_CHECK_HEADERS(jansson.h,
          AC_CHECK_LIB([jansson], [json_loads],
            EXT_LIB_PATH="-L$with_jansson/lib $EXT_LIB_PATH"
            jansson=1))
      ])
   ],
   [AC_MSG_RESULT([--with-jansson not specified])
    CHECK_LIBHEADER(JANSSON, jansson, json_loads, jansson.h,jansson=1,)])

AS_IF([test "x$jansson" != x1],
      [AC_MSG_ERROR([GNUnet requires libjansson])])

# check for sss (Shamir Secret Sharing) library
sss=0
AC_MSG_CHECKING(for sss)
AC_ARG_WITH(sss,
   [  --with-sss=PREFIX (base of sss installation)],
   [AC_MSG_RESULT([$with_sss])
    AS_CASE([$with_sss],
      [no],[],
      [yes],[
        CHECK_LIBHEADER(SSS, sss, sss_create_shares, sss.h, sss=1,)
      ],[
        LDFLAGS="-L$with_sss/lib $LDFLAGS"
        CPPFLAGS="-I$with_sss/include $CPPFLAGS"
        AC_CHECK_HEADERS(sss.h,
          AC_CHECK_LIB([sss], [sss_create_shares],
            EXT_LIB_PATH="-L$with_sss/lib $EXT_LIB_PATH"
            sss=1))
      ])
   ],
   [AC_MSG_RESULT([--with-sss not specified])
    CHECK_LIBHEADER(SSS, sss, sss_create_shares, sss.h,sss=1,)])
AM_CONDITIONAL(HAVE_SSS, [test "$sss" = 1])
AS_IF([test "$sss" = 1],
      [AC_DEFINE([HAVE_SSS],[1],[Have sss library])
       sss_msg="yes"],
      [AC_DEFINE([HAVE_SSS],[0],[Lacking sss library])
       sss_msg="no"])

# check for libpulse(audio) library
pulse=0
libpulse_msg="no"
AC_MSG_CHECKING(for libpulse)
# TODO: --with-libpulse or --with-pulseaudio? What is more established
# TODO: in this context?
AC_ARG_WITH(libpulse,
    [  --with-libpulse=PREFIX (base of libpulse installation)],
    [AC_MSG_RESULT([$with_libpulse])
     AS_CASE([$with_libpulse],
        [no],[],
        [yes],[
            CHECK_LIBHEADER(LIBPULSE,
                            pulse,
                            pa_stream_peek,
                            pulse/simple.h,
                            pulse=1,)
        ],[
            LDFLAGS="-L$with_libpulse/lib $LDFLAGS"
            CPPFLAGS="-I$with_libpulse/include $CPPFLAGS"
            AC_CHECK_HEADERS(pulse/simple.h,
                             AC_CHECK_LIB([pulse],
                                          [pa_stream_peek],
                                          EXT_LIB_PATH="-L$with_libpulse/lib $EXT_LIB_PATH"
                                          pulse=1))
        ])
    ],
    [AC_MSG_RESULT([--with-libpulse not specified])
     CHECK_LIBHEADER(LIBPULSE,
                     pulse,
                     pa_stream_peek,
                     pulse/simple.h,
                     pulse=1,)])
AM_CONDITIONAL(HAVE_PULSE, [test "$pulse" = 1])
AS_IF([test x"$pulse" = x1],
      [AC_DEFINE([HAVE_PULSE],[1],[Have libpulse(audio) library])
       libpulse_msg="yes"],
      [AC_DEFINE([HAVE_PULSE],[0],[Lacking libpulse(audio) library])
       libpulse_msg="no"])

# check for libopus(audio) library
opus=0
libopus_msg="no"
AC_MSG_CHECKING(for libopus)
AC_ARG_WITH(libopus,
    [  --with-libopus=PREFIX (base of libopus installation)],
    [AC_MSG_RESULT([$with_libopus])
     AS_CASE([$with_libopus],
        [no],[],
        [yes],[
            CHECK_LIBHEADER(LIBOPUS,
                            opus,
                            opus_decode_float,
                            opus/opus.h,
                            AC_CHECK_DECL([OPUS_SET_GAIN],
                                          [opus=1],
                                          [],
                                          [[
                                          #include <opus/opus.h>
                                          ]]))
    ],[
        LDFLAGS="-L$with_libopus/lib $LDFLAGS"
        CPPFLAGS="-I$with_libopus/include $CPPFLAGS"
        AC_CHECK_HEADERS(opus/opus.h,
                         AC_CHECK_LIB([opus],
                                      [OPUS_SET_GAIN],
                                      EXT_LIB_PATH="-L$with_libopus/lib $EXT_LIB_PATH"
                                      opus=1))
      ])
    ],
    [AC_MSG_RESULT([--with-libopus not specified])
     CHECK_LIBHEADER(LIBOPUS,
                     opus,
                     opus_decode_float,
                     opus/opus.h,
                     AC_CHECK_DECL([OPUS_SET_GAIN],
                                   [opus=1],
                                   [],
                                   [[
                                     #include <opus/opus.h>
                                   ]]))])
AM_CONDITIONAL(HAVE_OPUS, [test "$opus" = 1])
AS_IF([test "x$opus" = x1],
      [AC_DEFINE([HAVE_OPUS],[1],[Have libopus library])
       libopus_msg="yes"],
      [AC_DEFINE([HAVE_OPUS],[0],[Lacking libopus library])
       libopus_msg="no (required for conversation)"])

# libogg
AC_MSG_CHECKING(for libogg)
AC_ARG_WITH(libogg,
    [  --with-libogg=PREFIX (base of libogg installation)],
    [AC_MSG_RESULT([$with_libogg])
     AS_CASE([$with_libogg],
        [no],[],
        [yes],[
            CHECK_LIBHEADER(LIBOGG,
                            ogg,
                            ogg_stream_flush_fill,
                            ogg/ogg.h,
                            ogg=1,)
        ],[
            LDFLAGS="-L$with_libogg/lib $LDFLAGS"
            CPPFLAGS="-I$with_libogg/include $CPPFLAGS"
            AC_CHECK_HEADERS(ogg/ogg.h,
                             AC_CHECK_LIB([ogg],
                                          [ogg_stream_flush_fill],
                                          EXT_LIB_PATH="-L$with_libogg/lib $EXT_LIB_PATH"
                                          ogg=1))
        ])
     ],
     [AC_MSG_RESULT([--with-libogg not specified])
      CHECK_LIBHEADER(LIBOGG,
                      ogg,
                      ogg_stream_flush_fill,
                      ogg/ogg.h,
                      ogg=1,)])
AM_CONDITIONAL(HAVE_OGG, [test "$ogg" = 1])
AS_IF([test x"$ogg" = x1],
      [AC_DEFINE([HAVE_OGG],[1],[Have ogg])]
      [AC_DEFINE([HAVE_OGG],[0],[Lacking ogg])])


PKG_CHECK_MODULES([GLIB],
                  [glib-2.0],
  [# check for pbc library
  pbc=0
   AC_CHECK_HEADER([pbc/pbc.h],pbc=1)
   AC_CHECK_HEADER([gabe.h],abe=1)
   AM_CONDITIONAL(HAVE_PBC, [test "x$pbc" = x1])
   AM_CONDITIONAL(HAVE_ABE, [test "x$abe" = x1])
   AS_IF([test "x$pbc" = x1],
     [AC_DEFINE([HAVE_PBC],[1],[Have pbc library])],
     [AC_DEFINE([HAVE_PBC],[0],[Lacking pbc library])])
   AS_IF([test "x$abe" = x1],
    [AC_DEFINE([HAVE_ABE],[1],[Have ABE library])],
    [AC_DEFINE([HAVE_ABE],[0],[Lacking ABE library])])],
  [# glib-2 not found
   AM_CONDITIONAL(HAVE_PBC, [false])
   AM_CONDITIONAL(HAVE_ABE, [false])
   AC_DEFINE([HAVE_PBC],[0],[Lacking glib library])])


gst=0
gstreamer_msg="no"
AC_MSG_CHECKING(for gstreamer)
PKG_CHECK_MODULES(
  [GST],
  [glib-2.0 gobject-2.0 gstreamer-1.0 gstreamer-app-1.0 gstreamer-audio-1.0],
  [gst=1
   gstreamer_msg="yes"],
  [gst=0])

# conversation
AC_MSG_CHECKING(conversation feature set to build)
AS_IF([test "x$pulse" != "x1" -o "x$opus" != "x1" -o "x$ogg" != "x1"],[
 AS_IF([test "x$gst" != "x1"],[
  conversation_backend=none
  AM_CONDITIONAL(BUILD_PULSE_HELPERS, false)
  AM_CONDITIONAL(BUILD_GST_HELPERS, false)
  AM_CONDITIONAL(BUILD_EXPERIMENTAL_HELPERS, false)
 ],[
   conversation_backend=gst
   AM_CONDITIONAL(BUILD_PULSE_HELPERS, false)
   AM_CONDITIONAL(BUILD_GST_HELPERS, true)
   AM_CONDITIONAL(BUILD_EXPERIMENTAL_HELPERS, false)
 ])
],[
 conversation_backend=pulse
 AM_CONDITIONAL(BUILD_PULSE_HELPERS, true)
 AM_CONDITIONAL(BUILD_GST_HELPERS, false)
 AM_CONDITIONAL(BUILD_EXPERIMENTAL_HELPERS, false)
])

AS_IF([test "x$conversation_backend" = "xnone"],
      AM_CONDITIONAL(BUILD_CONVERSATION, false),
      AM_CONDITIONAL(BUILD_CONVERSATION, true))

# libgnurl
LIBGNURL_CHECK_CONFIG(,7.34.0,gnurl=1,gnurl=0)

SAVE_CPPFLAGS=$CPPFLAGS
CPPFLAGS="$LIBGNURL_CPPFLAGS $LIBCURL_CPPFLAGS $CPPFLAGS"
LIBS="$LIBGNURL $LIBCURL $LIBS"

# libcurl-gnutls
LIBCURL_CHECK_CONFIG(,7.34.0,[curl=true],[curl=false])
AS_IF([test "x$curl" = xtrue],[
 AC_CHECK_HEADER([curl/curl.h],
  AC_CHECK_DECLS(CURLINFO_TLS_SESSION,[curl=true],[curl=false],[[#include <curl/curl.h>]]),
  [curl=false])
 # need libcurl-gnutls.so for proxy, warn later if not found.
 AC_CHECK_LIB([curl-gnutls],[curl_easy_getinfo],[curl_gnutls=true],[curl_gnutls=false])
 # cURL must support CURLINFO_TLS_SESSION, version >= 7.34
])

# libcurl and libgnurl should be mutually exclusive
AS_IF([test "$gnurl" = 1],
      [AM_CONDITIONAL(HAVE_LIBGNURL, true)
       AC_DEFINE([HAVE_LIBGNURL],[1],[Have libgnurl])
       AM_CONDITIONAL(HAVE_LIBCURL, false)
       AC_DEFINE([HAVE_LIBCURL],[0],[Lacking libcurl])],
      [AS_IF([test "$curl" = true],
             [AM_CONDITIONAL(HAVE_LIBGNURL, false)
              AC_DEFINE([HAVE_LIBGNURL],[0],[Lacking libgnurl])
              AM_CONDITIONAL(HAVE_LIBCURL, true)
              AC_DEFINE([HAVE_LIBCURL],[1],[Have libcurl])],
             [AC_MSG_ERROR([GNUnet requires libcurl or gnurl >= 7.34])
              AM_CONDITIONAL(HAVE_LIBGNURL, false)
              AC_DEFINE([HAVE_LIBGNURL],[0],[Lacking libgnurl])
              AM_CONDITIONAL(HAVE_LIBCURL, false)
              AC_DEFINE([HAVE_LIBCURL],[0],[Lacking libcurl])])])

AC_SEARCH_LIBS(__atomic_load_8, atomic, [have_libatomic=1 AC_DEFINE(HAVE_LIBATOMIC,1,[external libatomic])])
AM_CONDITIONAL(HAVE_LIBATOMIC, [test "$have_libatomic" = 1])

# restore LIBS & CPPFLAGS
LIBS=$SAVE_LIBS
CPPFLAGS=$SAVE_CPPFLAGS


AC_CHECK_HEADERS([nss.h],[nss=true],[nss=false])
AS_IF([test x$nss = xfalse],
  [
	AM_CONDITIONAL(HAVE_GLIBCNSS, false)
	AC_MSG_WARN([No GNU libc nss header, will not build NSS plugin])
  ],[
	NSS_INCLUDES="
	#include <nss.h>
	"
	AC_CHECK_DECL([NSS_STATUS_UNAVAIL],
		[AM_CONDITIONAL(HAVE_GLIBCNSS, true)],
		[AM_CONDITIONAL(HAVE_GLIBCNSS, false)
		 AC_MSG_WARN([No nss header fails to define NSS_STATUS_UNAVAIl, will not build NSS plugin])],
		[$NSS_INCLUDES])
])



# test for kvm and kstat (for CPU stats under BSD/Solaris)
AC_CHECK_LIB([kvm],[kvm_open])
AC_CHECK_LIB([kstat],[kstat_open])

libsodium=0
# test for libsodium >=1.017 (introduction of
# crypto_scalarmult_ed25519_base_noclamp API)
AC_CHECK_HEADER([sodium.h],
                [AC_CHECK_LIB([sodium], [crypto_scalarmult_ed25519_base_noclamp],
                              [libsodium=1])])

AS_IF([test x$libsodium = x0],
      [AC_MSG_ERROR([GNUnet requires libsodium.])])

# test for libextractor
extractor=0
AC_MSG_CHECKING(for libextractor)
AC_ARG_WITH(extractor,
   [  --with-extractor=PREFIX (base of libextractor installation)],
   [AC_MSG_RESULT([$with_extractor])
    AS_CASE([$with_extractor],
      [no],[],
      [yes],[
        AC_CHECK_HEADERS([extractor.h],
          AC_CHECK_LIB([extractor], [EXTRACTOR_plugin_add_defaults],
            extractor=1))
      ],[
        LDFLAGS="-L$with_extractor/lib $LDFLAGS"
        CPPFLAGS="-I$with_extractor/include $CPPFLAGS"
        AC_CHECK_HEADERS([extractor.h],
          AC_CHECK_LIB([extractor], [EXTRACTOR_plugin_add_defaults],
            EXT_LIB_PATH="-L$with_extractor/lib $EXT_LIB_PATH"
            extractor=1))
      ])
   ],
   [AC_MSG_RESULT([--with-extractor not specified])
    AC_CHECK_HEADERS([extractor.h],
     AC_CHECK_LIB([extractor], [EXTRACTOR_plugin_add_defaults],
      extractor=1))])
# restore LIBS
LIBS=$SAVE_LIBS

AS_IF([test "$extractor" != 1],
 [
 AM_CONDITIONAL(HAVE_LIBEXTRACTOR, false)
 AC_DEFINE([HAVE_LIBEXTRACTOR],[0],[Lacking libextractor])
 ],[
 AM_CONDITIONAL(HAVE_LIBEXTRACTOR, true)
 AC_DEFINE([HAVE_LIBEXTRACTOR],[1],[Have libextractor])
 ])


# Check for libltdl header (#2999)
ltdl=0
AC_MSG_CHECKING(for libltdl)
AC_ARG_WITH(ltdl,
   [AS_HELP_STRING([--with-ltdl=PREFIX],[base of libltdl installation])],
   [AC_MSG_RESULT([$with_ltdl])
    AS_CASE([$with_ltdl],
      [no],[],
      [yes],[
        AC_CHECK_HEADERS(ltdl.h,
          AC_CHECK_LIB([ltdl], [lt_dlopenext],
            ltdl=1))
      ],[
        LDFLAGS="-L$with_ltdl/lib $LDFLAGS"
        CPPFLAGS="-I$with_ltdl/include $CPPFLAGS"
        AC_CHECK_HEADERS(ltdl.h,
          AC_CHECK_LIB([ltdl], [lt_dlopenext],
            EXT_LIB_PATH="-L$with_ltdl/lib $EXT_LIB_PATH"
            ltdl=1))
      ])
   ],
   [AC_MSG_RESULT([--with-ltdl not specified])
    AC_CHECK_HEADERS(ltdl.h,
     AC_CHECK_LIB([ltdl], [lt_dlopenext],
      ltdl=1))])
AS_IF([test x$ltdl = x1],
[
 AC_MSG_RESULT([libltdl found])
],[
 AC_MSG_ERROR([GNUnet requires libltdl (from GNU libtool).])
])
# restore LIBS
LIBS=$SAVE_LIBS

# libidn and libidn2. The ideal goal is this:
# check for libidn2, if it doesn't exist check for libidn
# if both exist, prefer libidn2
# if none exist, fail and message that libidn or libidn2
# is required with a preference for libidn2.
# TODO: What we have right here can probably be improved.
AC_MSG_CHECKING(for idn or idn2)

AC_MSG_CHECKING(for idn)
my_with_libidn=1
AC_ARG_WITH(libidn,
            AS_HELP_STRING([--with-libidn=pathname],
                           [Support IDN (needs libidn)]),
            [],
            [withval="yes"])
AS_IF([test x_$withval = x_yes],
      [AC_CHECK_HEADERS([idna.h],
                        AC_MSG_NOTICE([Found idna.h]),
                        AC_CHECK_HEADERS([idn/idna.h],
                                         AC_MSG_NOTICE([Found idn/idna.h]),
                                         my_with_libidn=0))],
      [AS_IF([test x_$withval != x_no],
             [CFLAGS="$CFLAGS -I$withval/include"
              LDFLAGS="$LDFLAGS -L$withval/lib"
              AC_CHECK_HEADERS([idna.h],
                               AC_MSG_NOTICE([Found idna.h]),
	                           [AC_MSG_NOTICE([Failed to find idna.h])
                               my_with_libidn=0])],
             [my_with_libidn=0])])

AC_MSG_CHECKING(for idn2)
my_with_libidn2=1
AC_ARG_WITH(libidn2,
            AS_HELP_STRING([--with-libidn2=pathname],
                           [Support IDN (needs libidn2)]),
            [],
            [withval="yes"])
AS_IF([test x_$withval = x_yes],
      [AC_CHECK_HEADERS([idn2.h],
                        AC_MSG_NOTICE([Found idn2.h]),
                        AC_CHECK_HEADERS([idn2/idn2.h],
                                         AC_MSG_NOTICE([Found idn2/idn2.h]),
                                         [AC_MSG_NOTICE([Failed to find idn2.h])
                                         my_with_libidn2=0]))],
      [AS_IF([test x_$withval != x_no],
             [CFLAGS="$CFLAGS -I$withval/include"
              LDFLAGS="$LDFLAGS -L$withval/lib"
              AC_CHECK_HEADERS([idn2/idn2.h],
                               AC_MSG_NOTICE([Found idn2/idn2.h]),
                               [AC_MSG_NOTICE([Failed to find idn2.h])
                               my_with_libidn2=0])],
             [my_with_libidn2=0])])

AC_MSG_CHECKING([if libidn can be used])
# Check for LIBIDNs
there_can_only_be_one=1

working_libidn1=0
working_libidn2=0
AS_IF([test x$my_with_libidn2 = x1],
      [AC_MSG_NOTICE([Checking for libidn2])
       AC_CHECK_LIB([idn2],
                    [idn2_to_unicode_8z8z],
                    [working_libidn2=1
                    LIBS="-lidn2 $LIBS"
 	            AC_DEFINE_UNQUOTED([HAVE_LIBIDN2],
                                       [1],
                                       [Define to 1 if you have 'libidn2' (-lidn2).])],
                    [MISSING_DEPS="${MISSING_DEPS}${MISSING_SEP}libidn2"
                     MISSING_SEP=", "])])
AM_CONDITIONAL(HAVE_LIBIDN2, test x$working_libidn2 = x1)
AS_IF([test x$working_libidn2 = x0],
      [AS_IF([test x$my_with_libidn = x1],
             [AC_MSG_NOTICE([Checking for libidn])
              AC_CHECK_LIB([idn],
                           [idna_to_ascii_8z],
                           [working_libidn1=1
                           LIBS="-lidn $LIBS"
                           AC_DEFINE_UNQUOTED([HAVE_LIBIDN],
                                              [1],
                                              [Define to 1 if you have 'libidn' (-lidn).])],
                           [there_can_only_be_one=0])],
             [AS_IF([test x$my_with_libidn2 = x1],
                    [there_can_only_be_one=0
                     AC_MSG_FAILURE([* There can only be one libidn.
                                     * Provide either libidn >= 1.13
                                     * or
                                     * libidn2 to the configure
                                     * script via
                                     * --with-libidn2
                                     * --with-libidn])])])])
AM_CONDITIONAL(HAVE_LIBIDN, test x$working_libidn1 = x1)

AS_IF([test "$working_libidn1" = 0 -a "$working_libidn2" = 0],
      [AC_MSG_ERROR([GNUnet requires libidn (or libidn2)])])

AS_IF([test x$there_can_only_be_one = x0],
      [AC_MSG_FAILURE([Missing dependencies: $MISSING_DEPS])])

# test for zlib
SAVE_LDFLAGS=$LDFLAGS
SAVE_CPPFLAGS=$CPPFLAGS
AC_ARG_WITH(zlib,
	    [  --with-zlib[[=DIR]]       use libz in DIR],
	    [AS_IF([test "$withval" = "no"],
		   [AC_MSG_ERROR([GNUnet requires zlib])],
		   [test "$withval" != "yes"],
		   [Z_DIR=$withval
		    CPPFLAGS="${CPPFLAGS} -I$withval/include"
		    LDFLAGS="${LDFLAGS} -L$withval/lib"])])
AC_CHECK_HEADER(zlib.h,
		[],
	       	[AC_MSG_ERROR([GNUnet requires zlib])])
AC_CHECK_LIB(z,
             compress2,
	     [AC_DEFINE([HAVE_ZLIB],
                        [],
                        [Have compression library])
	      if test "x${Z_DIR}" != "x"; then
		      Z_CFLAGS="-I${Z_DIR}/include"
		      Z_LIBS="-L${Z_DIR}/lib -lz"
	      else
		      Z_LIBS="-lz"
	      fi],
	      [AC_MSG_ERROR([GNUnet requires zlib])])
AC_SUBST(Z_CFLAGS)
AC_SUBST(Z_LIBS)

AS_IF([test "$enable_shared" = "no"],
      [AC_MSG_ERROR([GNUnet only works with shared libraries. Sorry.])])


# restore LIBS
LIBS=$SAVE_LIBS


# check for iconv
AM_ICONV

# test for libunistring
gl_LIBUNISTRING
AS_IF([test $HAVE_LIBUNISTRING != yes],
      [AC_MSG_ERROR([GNUnet requires libunistring])])

AS_IF([test "x$gl_libunistring_hexversion" = "x" || test "$gl_libunistring_hexversion" -le 2305],
      [AC_MSG_ERROR([GNUnet requires libunistring >= 0.9.1.1])])
AC_CHECK_HEADERS([unistr.h],
                 ,
                 AC_MSG_ERROR([Compiling GNUnet requires unistr.h (from libunistring) to be installed]))

# restore LIBS
LIBS=$SAVE_LIBS



# Checks for standard header files.
AC_HEADER_DIRENT
AC_HEADER_STDC

# Check for headers that are ALWAYS required
AC_CHECK_HEADERS([fcntl.h math.h errno.h ctype.h limits.h stdio.h stdlib.h string.h unistd.h stdarg.h signal.h locale.h sys/stat.h sys/types.h],,AC_MSG_ERROR([Compiling GNUnet requires standard UNIX headers files: fcntl.h math.h errno.h ctype.h limits.h stdio.h stdlib.h string.h unistd.h stdarg.h signal.h locale.h sys/stat.h sys/types.h]))



# Checks for headers that are only required on some systems or
# opional (and where we do NOT abort if they are not there)
AC_CHECK_HEADERS([stdatomic.h malloc.h malloc/malloc.h malloc/malloc_np.h langinfo.h sys/param.h sys/mount.h sys/statvfs.h sys/select.h sockLib.h sys/mman.h sys/msg.h sys/vfs.h arpa/inet.h fcntl.h libintl.h netdb.h netinet/in.h sys/ioctl.h sys/socket.h sys/time.h unistd.h kstat.h sys/sysinfo.h kvm.h sys/file.h sys/resource.h ifaddrs.h mach/mach.h stddef.h sys/timeb.h argz.h ucred.h sys/ucred.h endian.h sys/endian.h execinfo.h byteswap.h])

# FreeBSD requires this for netinet/in_systm.h and netinet/ip.h
AC_CHECK_HEADERS([sys/types.h netinet/in_systm.h netinet/in.h netinet/ip.h],,,
[#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_NETINET_IN_SYSTM_H
#include <netinet/in_systm.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
])

SAVE_LDFLAGS=$LDFLAGS
SAVE_CPPFLAGS=$CPPFLAGS

# test for sqlite
sqlite=false
AC_MSG_CHECKING(for SQLite)
AC_ARG_WITH(sqlite,
  [  --with-sqlite=PFX       base of SQLite installation],
  [AC_MSG_RESULT("$with_sqlite")
   AS_CASE([$with_sqlite],
     [no],[],
     [yes],[
      AC_CHECK_HEADERS(sqlite3.h,
      sqlite=true)],
     [
    LDFLAGS="-L$with_sqlite/lib $LDFLAGS"
    CPPFLAGS="-I$with_sqlite/include $CPPFLAGS"
    AC_CHECK_HEADERS(sqlite3.h,
     EXT_LIB_PATH="-L$with_sqlite/lib $EXT_LIB_PATH"
     SQLITE_LDFLAGS="-L$with_sqlite/lib"
     SQLITE_CPPFLAGS="-I$with_sqlite/include"
     sqlite=true)
    LDFLAGS=$SAVE_LDFLAGS
    CPPFLAGS=$SAVE_CPPFLAGS
    ])
  ],
  [AC_MSG_RESULT([--with-sqlite not specified])
    AC_CHECK_HEADERS(sqlite3.h, sqlite=true)])
AM_CONDITIONAL(HAVE_SQLITE, test x$sqlite = xtrue)
AC_SUBST(SQLITE_CPPFLAGS)
AC_SUBST(SQLITE_LDFLAGS)

LDFLAGS=$SAVE_LDFLAGS
CPPFLAGS=$SAVE_CPPFLAGS

# test for postgres:
postgres=false
AX_LIB_POSTGRESQL([9.5],
  [CPPFLAGS="$CPPFLAGS $POSTGRESQL_CPPFLAGS"
   AC_CHECK_HEADERS([libpq-fe.h],
   postgres=true)
  ],
  [AC_MSG_RESULT([no postgres])])

AM_CONDITIONAL(HAVE_POSTGRESQL, test x$postgres = xtrue)
AS_IF([test "x$postgres" = xtrue],
      [AC_DEFINE([HAVE_POSTGRESQL],[1],[Have PostgreSQL])],
      [AC_DEFINE([HAVE_POSTGRESQL],[0],[Lacking PostgreSQL])])

LDFLAGS=$SAVE_LDFLAGS
CPPFLAGS=$SAVE_CPPFLAGS

# mysql & windows
AC_CHECK_TYPES([sigset_t, off_t], [], [], [#include <sys/types.h>])
AC_CHECK_TYPES([size_t], [], [], [#include <stdio.h>])

# test for mysql
mysql=false
mysqlfail=false
SAVE_LDFLAGS=$LDFLAGS
SAVE_CPPFLAGS=$CPPFLAGS
AC_MSG_CHECKING(for mysql)
AC_ARG_WITH(mysql,
  [  --with-mysql=PFX        base of MySQL installation],
  [AC_MSG_RESULT([$with_mysql])
   AS_CASE([$with_mysql],
     [no],[],
     [yes|""],[
      AC_CHECK_HEADERS(mysql/mysql.h,
       AC_CHECK_LIB(mysqlclient, mysql_init,
       mysql=true), [], [])
     ],[
      LDFLAGS="-L$with_mysql/lib -L$with_mysql/lib/mysql $LDFLAGS $ZLIBS"
      CPPFLAGS="-I$with_mysql/include $CPPFLAGS"
      AC_CHECK_HEADERS(mysql/mysql.h,
       AC_CHECK_LIB(mysqlclient, mysql_init,
        MYSQL_LDFLAGS="-L$with_mysql/lib -L$with_mysql/lib/mysql"
        MYSQL_CPPFLAGS="-I$with_mysql/include"

        mysql=true), [], [])
     ])
  ],
  [AC_MSG_RESULT([--with-mysql not specified])
   if test -d "/usr/lib64/mysql"; then
    MYSQL_LIBDIR="/usr/lib64/mysql"
   elif test -d "/usr/lib/mysql"; then
    MYSQL_LIBDIR="/usr/lib/mysql"
   else
    MYSQL_LIBDIR="/usr/lib"
   fi
   LDFLAGS="-L$MYSQL_LIBDIR $LDFLAGS $ZLIBS"
   AC_CHECK_LIB(mysqlclient, mysql_init,
    [AC_CHECK_HEADERS(mysql/mysql.h,
      MYSQL_LDFLAGS="-L$MYSQL_LIBDIR"
      mysql=true

     , [], [])])
  ])

AC_SUBST(MYSQL_LDFLAGS)
AC_SUBST(MYSQL_CPPFLAGS)

# additional version check for mysql
AC_ARG_ENABLE(mysql-version-check, [  --disable-mysql-version-check  do not check MySQL version],, enable_mysql_version_check=yes)
AS_IF([test "$mysql" = "true" -a "x$enable_mysql_version_check" = "xyes"],
 [
  AC_MSG_CHECKING(mysql version)
  AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
    [[
      #include <mysql/mysql_version.h>]],
    [[
      #if (MYSQL_VERSION_ID < 40100)
      #error needs at least version >= 4.1
      #endif
    ]])
    ],
    [mysql=true],
    [mysql=false])
  AS_IF([test x$mysql = xfalse],
   [
    mysqlfail=true
    AC_MSG_WARN([fail, MySQL >= 4.1 required])
   ],[
    AC_MSG_NOTICE([success, will keep $mysqlfail])
    mysqlfail=false
    AC_MSG_RESULT(ok)
   ])
  AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
    [[
      #include <mysql/mysql_version.h>]],
    [[
      #if (MYSQL_VERSION_ID < 80000)
      #error needs at least version >= 4.1
      #endif
    ]])
    ],
    [mysql8=true],
    [mysql8=false])
  AS_IF([test x$mysql8 = xtrue],
   [
    AC_DEFINE([HAVE_MYSQL8],[1],[Have mysql8])
   ],[])
])

AM_CONDITIONAL(HAVE_MYSQL, test x$mysql = xtrue)
AM_CONDITIONAL(HAVE_MYSQLE, false)
# restore LIBS
LIBS=$SAVE_LIBS
LDFLAGS=$SAVE_LDFLAGS
CPPFLAGS=$SAVE_CPPFLAGS

# TODO: should this test for "or" not "and"?
# TODO: Add postgres?
AS_IF([test "$sqlite" = 0 -a "$mysql" = 0],
[
 AC_MSG_ERROR([GNUnet requires SQLite or MySQL / MariaDB.])
])

# libmicrohttpd
lmhd=0
m4_define([MHD_MODULE], [libmicrohttpd >= 0.9.63])
AC_ARG_WITH(microhttpd,
   [AS_HELP_STRING([--with-microhttpd[[=PFX]]],
       [base of libmicrohttpd installation])],
   [],
   [with_microhttpd=check])
AS_CASE([$with_microhttpd],
   [no], [],
   [yes], [PKG_CHECK_MODULES([MHD], [MHD_MODULE], [lmhd=1])],
   [check], [PKG_CHECK_MODULES([MHD], [MHD_MODULE],
       [lmhd=1],
       [AC_MSG_WARN([Building without libmicrohttpd])])],
   [SAVE_PKG_CONFIG_PATH=$PKG_CONFIG_PATH
    PKG_CONFIG_PATH=$with_microhttpd/lib/pkgconfig
    export PKG_CONFIG_PATH
    PKG_CHECK_MODULES([MHD], [MHD_MODULE], [lmhd=1])
    PKG_CONFIG_PATH=$SAVE_PKG_CONFIG_PATH])
AM_CONDITIONAL(HAVE_MHD, test x$lmhd = x1)
AC_DEFINE_UNQUOTED([HAVE_MHD], $lmhd, [We have libmicrohttpd])

AM_CONDITIONAL(HAVE_JSON, [test x$jansson = x1])
AM_CONDITIONAL(HAVE_REST, [test x$jansson = x1 -a x$lmhd = x1])
AS_IF([test "x$lmhd" != "x1"],
      [AC_MSG_ERROR([GNUnet requires libmicrohttpd >= 0.9.63.])])


# restore LIBS
LIBS=$SAVE_LIBS

# check for gettext
AM_GNU_GETTEXT([external])
AM_GNU_GETTEXT_VERSION([0.18.1])

# Checks for standard typedefs, structures, and compiler characteristics.
AC_TYPE_PID_T
AC_TYPE_SIZE_T
AC_TYPE_MODE_T
AC_HEADER_TIME
AC_HEADER_STAT
AC_HEADER_STDBOOL
AC_STRUCT_TM

AC_CHECK_MEMBER([struct sockaddr_in.sin_len],
   [ AC_DEFINE(HAVE_SOCKADDR_IN_SIN_LEN, 1, [Do we have sockaddr_in.sin_len?])
   ],
   [],
   [
      #include <sys/types.h>
      #include <sys/socket.h>
      #include <netinet/in.h>
   ])

AC_CHECK_MEMBER([struct sockaddr_un.sun_len],
                [ AC_DEFINE(HAVE_SOCKADDR_UN_SUN_LEN,
                            1,
                            [Do we have sockaddr_un.sun_len?])],
                [],
                [
                #include <sys/types.h>
                #include <sys/socket.h>
                #include <sys/un.h>
                ])



# Checks for library functions.
AC_FUNC_CLOSEDIR_VOID
AC_FUNC_FORK
AC_PROG_GCC_TRADITIONAL
AC_FUNC_MEMCMP
AC_FUNC_SELECT_ARGTYPES
AC_FUNC_CHOWN

AC_TYPE_SIGNAL
AC_FUNC_STAT
AC_FUNC_STRFTIME
AC_FUNC_VPRINTF
AC_HEADER_SYS_WAIT
AC_TYPE_OFF_T
AC_TYPE_UID_T
AC_CHECK_FUNCS([atoll stat64 strnlen mremap getrlimit setrlimit sysconf initgroups strndup gethostbyname2 getpeerucred getpeereid setresuid $funcstocheck getifaddrs freeifaddrs getresgid mallinfo malloc_size malloc_usable_size getrusage random srandom stat statfs statvfs wait4])

# restore LIBS
LIBS=$SAVE_LIBS

GN_INTLINCL=""
GN_LIBINTL="$LTLIBINTL"
GN_LIB_LDFLAGS="-export-dynamic -no-undefined"
GN_PLUGIN_LDFLAGS="-export-dynamic -avoid-version -module -no-undefined"

AC_SUBST(GN_LIB_LDFLAGS)
AC_SUBST(GN_PLUGIN_LDFLAGS)
AC_SUBST(GN_INTLINCL)
AC_SUBST(GN_LIBINTL)

AC_SUBST(CPPFLAGS)
AC_SUBST(LIBS)
AC_SUBST(LDFLAGS)
AC_SUBST(EXT_LIB_PATH)
AC_SUBST(EXT_LIBS)

AC_SUBST(LIBPREFIX)
AC_SUBST(DLLDIR)
AC_SUBST(EXT_LIB_PATH)

DATAROOTDIR=$datarootdir
AC_SUBST(DATAROOTDIR)

# test for sudo
AC_MSG_CHECKING(for sudo)
#AC_CHECK_PROGS(SUDO_BINARY, [sudo], false)
#AM_CONDITIONAL(HAVE_SUDO, test x$SUDO_BINARY != xfalse)
AC_ARG_WITH(sudo,
           [  --with-sudo=PATH       path to sudo binary (or just yes)],
           [AC_MSG_RESULT("$with_sudo")
            AS_CASE([$with_sudo],
                    [no],[SUDO_BINARY=],
                    [yes],[SUDO_BINARY=sudo],
                    [SUDO_BINARY=$with_sudo])],
           [AC_MSG_RESULT([no])])
AC_SUBST(SUDO_BINARY)
AM_CONDITIONAL([HAVE_SUDO],
              [test "x$SUDO_BINARY" != "x" -o -w /])

# test for doas
AC_MSG_CHECKING(for doas)
AC_CHECK_PROGS(DOAS_BINARY, [doas], false)
AM_CONDITIONAL(HAVE_DOAS_BINARY, test x$DOAS_BINARY != xfalse)

# test for gnunetdns group name
GNUNETDNS_GROUP=gnunetdns
AC_MSG_CHECKING(for gnunetdns group name)
AC_ARG_WITH(gnunetdns,
            [  --with-gnunetdns=GRPNAME       name for gnunetdns group],
            [AC_MSG_RESULT("$with_gnunetdns")
             AS_CASE([$with_gnunetdns],
                     [no],[GNUNETDNS_GROUP=gnunet],
                     [yes],[GNUNETDNS_GROUP=gnunetdns],
                     [GNUNETDNS_GROUP=$with_gnunetdns])],
            [AC_MSG_RESULT([gnunetdns])])
AC_SUBST(GNUNETDNS_GROUP)



# gnutls
gnutls=0
gnutls_dane=0
AC_MSG_CHECKING(for gnutls)
AC_ARG_WITH(gnutls,
            [  --with-gnutls=PFX   base of gnutls installation],
            [AC_MSG_RESULT([$with_gnutls])
             AS_CASE([$with_gnutls],
                     [no],[],
                     [yes],
                     [AC_CHECK_HEADERS([gnutls/abstract.h],
                                       AC_CHECK_LIB([gnutls],
                                                    [gnutls_priority_set],
	                                            gnutls=true))
                      AC_CHECK_HEADERS([gnutls/dane.h],
                                       AC_CHECK_LIB([gnutls-dane],
                                                    [dane_verify_crt_raw],
	                                            gnutls_dane=1))],

        [LDFLAGS="-L$with_gnutls/lib $LDFLAGS"
        CPPFLAGS="-I$with_gnutls/include $CPPFLAGS"
        AC_CHECK_HEADERS([gnutls/abstract.h],
            AC_CHECK_LIB([gnutls], [gnutls_priority_set],
              EXT_LIB_PATH="-L$with_gnutls/lib $EXT_LIB_PATH"
              gnutls=true))
        AC_CHECK_HEADERS([gnutls/dane.h],
            AC_CHECK_LIB([gnutls-dane], [dane_verify_crt_raw],
	      gnutls_dane=1))
      ])
   ],
   [AC_MSG_RESULT([--with-gnutls not specified])
    AC_CHECK_HEADERS([gnutls/abstract.h],
        AC_CHECK_LIB([gnutls], [gnutls_priority_set],
          gnutls=true))
    AC_CHECK_HEADERS([gnutls/dane.h],
        AC_CHECK_LIB([gnutls-dane], [dane_verify_crt_raw],
    	             gnutls_dane=1))
   ])
AM_CONDITIONAL(HAVE_GNUTLS, test x$gnutls = xtrue)
AC_DEFINE_UNQUOTED([HAVE_GNUTLS], $gnutls, [We have GnuTLS])
AM_CONDITIONAL(HAVE_GNUTLS_DANE, test x$gnutls_dane = x1)
AC_DEFINE_UNQUOTED([HAVE_GNUTLS_DANE], $gnutls_dane, [We have GnuTLS with DANE support])



# Test if we are building for superMUC
AC_MSG_CHECKING(if GNUnet is being configured to run on the SuperMUC)
AC_ARG_ENABLE([supermuc],
    [AS_HELP_STRING([--enable-supermuc],
       [build GNUnet with support to run on the SuperMUC (default is NO)])],
    [AS_IF([test "x$enable_supermuc" = "xno"],
      [supermuc=0],
      [supermuc=1])],
    [supermuc=0
     enable_supermuc=no])
AC_MSG_RESULT($enable_SUPERMUC)
AM_CONDITIONAL([ENABLE_SUPERMUC], [test "x$supermuc" = "x1"])
AC_DEFINE_UNQUOTED([ENABLE_SUPERMUC], [$supermuc], [Build with support for SuperMUC])

# Check if NSE has to send timestamp information to testbed logger for
# generating histogram of messages received
AC_MSG_CHECKING(if NSE has to send timestamp information to testbed logger)
AC_ARG_ENABLE([nse-histogram],
    [AS_HELP_STRING([--enable-nse-histogram],
       [have NSE send timestamp information to testbed logger for generating
       histogram of received messages.  NOT useful for production (default is
       NO)])],
    [AS_IF([test "x$enableval" = "xno"],
      [nse_histogram=0],
      [nse_histogram=1])],
    [nse_histogram=0
     enable_nse_histogram=no])
AC_MSG_RESULT($enable_nse_histogram)
AM_CONDITIONAL([ENABLE_NSE_HISTOGRAM], [test "x$nse_histogram" = "x1"])
AC_DEFINE_UNQUOTED([ENABLE_NSE_HISTOGRAM], [$nse_histogram],
                   [have NSE send timestamp information to testbed logger])

# should 'make check' run tests?
AC_MSG_CHECKING(whether to run tests)
AC_ARG_ENABLE([testruns],
   [AS_HELP_STRING([--disable-testruns], [disable running tests on make check (default is YES)])],
   [enable_tests_run=${enableval}],
   [enable_tests_run=yes])
AC_MSG_RESULT($enable_test_run)
AM_CONDITIONAL([ENABLE_TEST_RUN], [test "x$enable_tests_run" = "xyes"])


AC_MSG_CHECKING([whether to compile in benchmarks (currently for http and crypto)])
AC_ARG_ENABLE([benchmark],
   [AS_HELP_STRING([--enable-benchmark], [enable benchmarking])],
   [enable_benchmark=${enableval}],
   [enable_benchmark=no])
AC_MSG_RESULT($enable_benchmark)
AS_IF([test "x$enable_benchmark" = "xyes"],
      [AC_DEFINE_UNQUOTED(ENABLE_BENCHMARK,1,[Benchmarks are enabled])])
AM_CONDITIONAL([ENABLE_BENCHMARK], [test "x$enable_benchmark" = "xyes"])


# should expensive tests be run?
AC_MSG_CHECKING(whether to run expensive tests)
AC_ARG_ENABLE([expensivetests],
   [AS_HELP_STRING([--enable-expensivetests], [enable running expensive testcases])],
   [enable_expensive=${enableval}],
   [enable_expensive=no])
AC_MSG_RESULT($enable_expensive)
AM_CONDITIONAL([HAVE_EXPENSIVE_TESTS], [test "x$enable_expensive" = "xyes"])

# should ports be open for Java services?
AC_MSG_CHECKING(whether to enable ports for gnunet-java)
AC_ARG_ENABLE([javaports],
   [AS_HELP_STRING([--enable-javaports], [use non-zero ports for services with Java bindings (default is NO)])],
   [enable_java_ports=${enableval}],
   [enable_java_ports=no])
AC_MSG_RESULT($enable_java_ports)
AS_IF([test "x$enable_java_ports" = "xyes"],
 [JAVAPORT=""],
 [JAVAPORT="$UNIXONLY"])
AC_SUBST(JAVAPORT)

# should benchmarks be run?
AC_MSG_CHECKING(whether to run benchmarks during make check)
AC_ARG_ENABLE([benchmarks],
   [AS_HELP_STRING([--enable-benchmarks], [enable running benchmarks during make check])],
   [enable_benchmarks=${enableval}],
   [enable_benchmarks=no])
AC_MSG_RESULT($enable_benchmarks)
AM_CONDITIONAL([HAVE_BENCHMARKS], [test "x$enable_benchmarks" = "xyes"])

# should gnunet-testing be compiled
AC_MSG_CHECKING(whether to compile gnunet-testing)
AC_ARG_ENABLE([testing],
   [AS_HELP_STRING([--disable-testing], [do not build gnunet-testing])],
   [enable_testing=${enableval}],
   [enable_testing=yes])
AC_MSG_RESULT($enable_testing)
AM_CONDITIONAL([HAVE_TESTING], [test "x$enable_testing" = "xyes"])

# should experimental code be compiled (code that may not yet compile)?
AC_MSG_CHECKING(whether to compile experimental code)
AC_ARG_ENABLE([experimental],
   [AS_HELP_STRING([--enable-experimental], [enable compiling experimental code])],
   [enable_experimental=${enableval}],
   [enable_experimental=no])
AC_MSG_RESULT($enable_experimental)
AM_CONDITIONAL([HAVE_EXPERIMENTAL], [test "x$enable_experimental" = "xyes"])

# should malicious code be compiled (should only be used for testing)?
AC_MSG_CHECKING(whether to compile malicious code)
AC_ARG_ENABLE([malicious],
   [AS_HELP_STRING([--enable-malicious], [enable compiling malicious code])],
   [AS_IF([test "x$enableval" = "xno"],
     [malicious=0],
     [malicious=1])],
   [malicious=0
    enable_malicious=no])
AC_MSG_RESULT($enable_malicious)
AM_CONDITIONAL([ENABLE_MALICIOUS], [test 1=$malicious])
AC_DEFINE_UNQUOTED([ENABLE_MALICIOUS], [$malicious],
                   [enable compilation of malicious code])

# should services be started on demand when needed?
# Some services may choose to never start by default
# and it is up to the service/module developer to decide
# by having "START_ON_DEMAND = NO" instead of
# "START_ON_DEMAND = @START_ON_DEMAND@"
# in the service/module's conf.in file.
# See also IMMEDIATE_START for an unconditional immediate start.
START_ON_DEMAND="YES"
AC_MSG_CHECKING(whether to start peer's services on demand by default)
AC_ARG_ENABLE([autostart],
   [AS_HELP_STRING([--disable-autostart], [do not start peer's services by default])],
   [enable_autostart=${enableval}
    AS_IF([test "x$enable_autostart" = "xno"],
      [START_ON_DEMAND="NO"])
   ],
   [enable_autostart=yes])
AC_MSG_RESULT($enable_autostart)
#AM_CONDITIONAL([HAVE_START_ON_DEMAND], [test "x$enable_autostart" = "xyes"])
AC_SUBST(START_ON_DEMAND)

# should memory statistics be kept (very expensive CPU-wise!)
AC_MSG_CHECKING(whether to create expensive statistics on memory use)
AC_ARG_ENABLE([heapstats],
   [AS_HELP_STRING([--enable-heapstats], [enable expensive heap statistics])],
   [enable_heapstats=1],
   [enable_heapstats=0])
AC_MSG_RESULT($enable_heapstats)
AC_DEFINE_UNQUOTED([ENABLE_HEAP_STATISTICS],$enable_heapstats,[enable expensive heap statistics])


# Check if the __thread storage class for
# thread-local storage is available.
AC_MSG_CHECKING(whether __thread is supported)
AC_LINK_IFELSE(
[AC_LANG_PROGRAM([#include <stdlib.h>
                   #undef __thread
                   static __thread int a = 1;],
                  [exit(a-1);])],
 [have_thread_local_gcc=1],[have_thread_local_gcc=0])
AC_DEFINE_UNQUOTED([HAVE_THREAD_LOCAL_GCC],$have_thread_local_gcc,[Define this if __thread is supported])
AS_IF([test "x$have_thread_local_gcc" = "x1"],
      [AC_MSG_RESULT(yes)],
      [AC_MSG_RESULT(no)])

# gcov compilation
AC_MSG_CHECKING(whether to compile with support for code coverage analysis)
AC_ARG_ENABLE([coverage],
              AS_HELP_STRING([--enable-coverage],
                             [compile the library with code coverage support]),
              [use_gcov=${enableval}],
              [use_gcov=no])
AC_MSG_RESULT($use_gcov)
AM_CONDITIONAL([USE_COVERAGE], [test "x$use_gcov" = "xyes"])


# version info
# TODO: git blame says this predates our switch to git.
# git-svn should be adjusted to simply git, or
# an external script that does the job.
AC_PATH_PROG(svnversioncommand, svnversion)
AC_PATH_PROG(gitcommand, git)
AC_MSG_CHECKING(for source being under a VCS)


# version info
AC_PATH_PROG(gitcommand, git)
AC_MSG_CHECKING(for source being under a VCS)
git_version=
AS_IF([test ! "X$gitcommand" = "X"],
[
  git_version=$(cd $srcdir ; git rev-list --full-history --all --abbrev-commit | head -n 1 2>/dev/null)
])
AS_IF([test "X$git_version" = "X"],
  [
    vcs_name="no"
    vcs_version="\"release\""
  ],
  [
    vcs_name="yes, git-svn"
    vcs_version="\"git-$git_version\""
  ])
AC_MSG_RESULT($vcs_name)

AC_MSG_CHECKING(VCS version)
AC_MSG_RESULT($vcs_version)
AC_DEFINE_UNQUOTED(VCS_VERSION, [$vcs_version], [VCS revision/hash or tarball version])

AC_CONFIG_FILES([
Makefile
bin/Makefile
contrib/Makefile
contrib/hellos/Makefile
contrib/services/Makefile
contrib/services/openrc/Makefile
contrib/services/systemd/Makefile
contrib/scripts/Makefile
contrib/scripts/gnunet-logread/Makefile
doc/Makefile
doc/man/Makefile
doc/doxygen/Makefile
doc/handbook/Makefile
doc/tutorial/Makefile
m4/Makefile
po/Makefile.in
src/Makefile
src/arm/Makefile
src/arm/arm.conf
src/ats/Makefile
src/ats/ats.conf
src/ats-tool/Makefile
src/ats-tests/Makefile
src/auction/Makefile
src/block/Makefile
src/cadet/Makefile
src/cadet/cadet.conf
src/core/Makefile
src/core/core.conf
src/consensus/Makefile
src/consensus/consensus.conf
src/conversation/Makefile
src/conversation/conversation.conf
src/curl/Makefile
src/datacache/Makefile
src/datastore/Makefile
src/datastore/datastore.conf
src/dht/Makefile
src/dht/dht.conf
src/dns/Makefile
src/dns/dns.conf
src/exit/Makefile
src/fragmentation/Makefile
src/fs/Makefile
src/fs/fs.conf
src/gns/Makefile
src/gns/gns.conf
src/gns/nss/Makefile
src/gnsrecord/Makefile
src/hello/Makefile
src/identity/Makefile
src/identity/identity.conf
src/abd/Makefile
src/abd/abd.conf
src/include/Makefile
src/integration-tests/Makefile
src/json/Makefile
src/hostlist/Makefile
src/my/Makefile
src/mysql/Makefile
src/namecache/Makefile
src/namecache/namecache.conf
src/namestore/Makefile
src/namestore/namestore.conf
src/nat/Makefile
src/nat/nat.conf
src/nat-auto/Makefile
src/nat-auto/nat-auto.conf
src/nse/Makefile
src/nse/nse.conf
src/nt/Makefile
src/peerinfo/Makefile
src/peerinfo/peerinfo.conf
src/peerinfo-tool/Makefile
src/peerstore/Makefile
src/peerstore/peerstore.conf
src/pq/Makefile
src/pt/Makefile
src/regex/Makefile
src/regex/regex.conf
src/revocation/Makefile
src/revocation/revocation.conf
src/rps/Makefile
src/rps/rps.conf
src/secretsharing/Makefile
src/secretsharing/secretsharing.conf
src/scalarproduct/Makefile
src/scalarproduct/scalarproduct.conf
src/set/Makefile
src/set/set.conf
src/seti/Makefile
src/seti/seti.conf
src/setu/Makefile
src/setu/setu.conf
src/sq/Makefile
src/statistics/Makefile
src/statistics/statistics.conf
src/template/Makefile
src/testbed/Makefile
src/testbed/testbed.conf
src/testbed-logger/Makefile
src/testbed-logger/testbed-logger.conf
src/testing/Makefile
src/topology/Makefile
src/transport/Makefile
src/transport/transport.conf
src/util/Makefile
src/util/resolver.conf
src/vpn/Makefile
src/vpn/vpn.conf
src/zonemaster/Makefile
src/zonemaster/zonemaster.conf
src/rest/Makefile
src/abe/Makefile
src/reclaim/Makefile
src/escrow/Makefile
pkgconfig/Makefile
pkgconfig/gnunetarm.pc
pkgconfig/gnunetats.pc
pkgconfig/gnunetblock.pc
pkgconfig/gnunetcadet.pc
pkgconfig/gnunetconsensus.pc
pkgconfig/gnunetconversation.pc
pkgconfig/gnunetcore.pc
pkgconfig/gnunetdatacache.pc
pkgconfig/gnunetdatastore.pc
pkgconfig/gnunetdht.pc
pkgconfig/gnunetdns.pc
pkgconfig/gnunetenv.pc
pkgconfig/gnunetfragmentation.pc
pkgconfig/gnunetfs.pc
pkgconfig/gnunetgns.pc
pkgconfig/gnunethello.pc
pkgconfig/gnunetidentity.pc
pkgconfig/gnunetmicrophone.pc
pkgconfig/gnunetmysql.pc
pkgconfig/gnunetnamestore.pc
pkgconfig/gnunetnat.pc
pkgconfig/gnunetnse.pc
pkgconfig/gnunetpeerinfo.pc
pkgconfig/gnunetpq.pc
pkgconfig/gnunetregex.pc
pkgconfig/gnunetrevocation.pc
pkgconfig/gnunetrps.pc
pkgconfig/gnunetscalarproduct.pc
pkgconfig/gnunetset.pc
pkgconfig/gnunetspeaker.pc
pkgconfig/gnunetstatistics.pc
pkgconfig/gnunettestbed.pc
pkgconfig/gnunettesting.pc
pkgconfig/gnunettransport.pc
pkgconfig/gnunetutil.pc
pkgconfig/gnunetvpn.pc
])
AC_OUTPUT


# FIXME: `some modules' -> be more specific which exact modules.

# java ports
AS_IF([test "x$enable_java_ports" = "xyes"],
      [AC_MSG_NOTICE([Opening TCP ports by default to enable gnunet-java bindings.])])

####
#### This could be moved to the checks above,
#### but for now let's keep it here.
####
transport_msg="tcp udp unix http"
AS_IF([test "x$build_target" = "xlinux" -a "x$enable_experimental" = "xyes"],
      [transport_msg="$transport_msg wlan"])
# -- print message regarding enabled experimental features
experimental_msg="no"
AS_IF([test "x$enable_experimental" = "xyes"],
      [experimental_msg="yes"])
# -- libidn 2
AS_IF([test "x$working_libidn2" = x1],
      [libidn2_msg="libidn2"])
# -- libidn 1
AS_IF([test "x$working_libidn1" = x1],
      [libidn1_msg="libidn1"])
# -- texi2mdoc-generation
AS_IF([test "x$texi2mdoc_generation" = "xyes"],
      [mdocml_msg="yes"],
      [mdocml_msg="no"])
# -- texi2mdoc
AS_IF([test "x$TEXI2MDOC_BINARY" = "false"],
      [AC_MSG_NOTICE([texi2mdoc binary not found (will not generate mdoc documentation)])
       texi2mdoc_msg="no (optional)"],
      [texi2mdoc_msg="yes"])
# -- mandoc
AS_IF([test "x$MANDOC_BINARY" = "false"],
      [AC_MSG_NOTICE([mandoc binary not found (will not generate handbook as man page)])
       mandoc_msg="no"],
      [mandoc_msg="yes"])
# -- texinfo
AS_IF([test "x$makeinfo" != "x1"],
      [texinfo_msg="no"],
      [texinfo_msg="yes"])
# -- conversation
conversation_msg="no"
AS_IF([test "x$conversation_backend" = "xnone"],
      [AS_IF([test "x$pulse" != "x1"],
             [libpulse_msg="no (required for conversation)"],
             [libpulse_msg="yes"])
       AS_IF([test "x$opus" != "x1"],
             [libopus_msg="no (required for conversation)"],
             [libopus_msg="yes"])
       AS_IF([test "x$gst" != "x1"],
             [gstreamer_msg="no (required for conversation)"],
             [gstreamer_msg="yes"])],
      [AS_IF([test "x$opus" = x1],
             [conversation_msg="yes (x$conversation_backend)"],
             [AC_MSG_WARN([libopus not found (required to build conversation)])])])

# -- interface
interface_msg=`echo $DEFAULT_INTERFACE | tr -d \"`
# -- jansson
# -- sss
AS_IF([test "$sss" != 1],
      [AC_MSG_WARN([sss library not found. GNS escrow plugin will not be compiled.])],
      [sss_msg="yes"])
# -- libextractor
AS_IF([test "$extractor" != 1],
      [AC_MSG_WARN([libextractor not found, but various file-sharing functions require it])],
      [libextractor_msg="yes"])
# -- libzbar
AS_IF([test "x$zbar" = "x1"],
      [libzbar_msg="yes"],
      [libzbar_msg="no (gnunet-qr will not be built)"])
# -- libgnurl
AS_IF([test "$gnurl" = "0"],
      [AS_IF([test "x$curl" = "xfalse"],
             [AC_MSG_WARN([libgnurl not found. http client support will not be compiled.])
              AC_MSG_WARN([IMPORTANT: No HTTP client library found. HTTP transports and hostlist daemon will not be compiled, and you probably WANT the hostlist daemon])
              http_client="none"],
             [AC_MSG_NOTICE([Using libcurl as HTTP client library.])
              http_client="curl"])],
       [AC_MSG_NOTICE([Using libgnurl as HTTP client library.])
        http_client="gnurl"])
AS_IF([test "x$curl" = "xtrue" -a "x$curl_gnutls" != "xtrue"],
      [AC_MSG_WARN([libcurl TLS backend is not gnutls. The GNS Proxy will likely not function properly.])
       http_client="curl-openssl"],
      [http_client="curl-gnutls"])
# -- ifconfig
AS_IF([test "$VAR_IFCONFIG_BINARY" = "false"],
      [ifconfig_msg="no (optional, some features will not work)"],
      [ifconfig_msg="yes"])
# -- upnpc
AS_IF([test "$VAR_UPNPC_BINARY" = "false"],
      [upnpc_msg="no (optional, NAT traversal using UPnPc will not work)"],
      [upnpc_msg="yes"])
# -- iptables
AS_IF([test "$VAR_IPTABLES_BINARY" = "false"],
      [iptables_msg="no (optional, DNS query interception will not work)"],
      [iptables_msg="yes"])
# -- bluetooth
AS_IF([test "x$bluetooth" = "x0"],
      [bluetooth_msg="no (optional)"],
      [bluetooth_msg="yes"
       transport_msg="$transport_msg bluetooth"])
# -- gnutls
AS_IF([test x$gnutls != xtrue],
      [AC_MSG_WARN([GnuTLS not found, gnunet-gns-proxy will not be built])
       gnutls_msg="no (gnunet-gns-proxy will not be built)"],
      [AS_IF([test "x$gnutls_dane" != "x1"],
             [AC_MSG_WARN([GnuTLS lacks DANE support, DANE validation will not be possible])
              gnutls_msg="yes (without DANE support)"],
             [gnutls_msg="yes (with DANE support)"])])
# -- databases
# TODO: this always returns true, the check might
# TODO: not be working as intended (for msqlfail).
AS_IF([test "$mysql" = true],
      [features_msg="$features_msg mysql"
       mysql_msg="yes"],
      [mysql_msg="no"])
AS_IF([test x$mysqlfail = xtrue],
      [AC_MSG_WARN([MySQL not found (or too old), will not create MySQL database support])
       mysql_msg="unsupported version"])
AS_IF([test "$sqlite" = true],
      [features_msg="$features_msg sqlite"
       sqlite_msg="yes"],
      [AC_MSG_ERROR([sqlite3 not found, but sqlite3 is required.])
       sqlite_msg="no"])
AS_IF([test "$postgres" = true],
      [features_msg="$features_msg postgres"
       postgres_msg="yes"],
      [postgres_msg="no"])
# -- features
# ---- 1. replace spaces with newlines,
# ---- 2. sort the lines,
# ---- 3. replace the newlines with spaces.
features_msg=`echo $features_msg | tr ' ' '\012' | sort | tr '\012' ' '`
AC_SUBST(features_msg)


# The summary
# TODO: reduce the length of the last message block, following "IMPORTANT".

AC_MSG_NOTICE([
Detected system
===============

GNUnet version:                 ${VERSION}

Host setup:                     ${host}
Install prefix:                 ${prefix}
Compiler:                       ${CC}
CFLAGS:                         ${CFLAGS}
CPPFLAGS:                       ${CPPFLAGS}
LDFLAGS:                        ${LDFLAGS}
LIBS:                           ${LIBS}
Build Target:                   $build_target

Default Interface:              ${interface_msg}

MySQL:                          ${mysql_msg}
PostgreSQL:                     ${postgres_msg}
sqlite3:                        ${sqlite_msg}
http client:                    ${http_client}
bluetooth:                      ${bluetooth_msg}
iptables:                       ${iptables_msg}
ifconfig:                       ${ifconfig_msg}
upnpc:                          ${upnpc_msg}
gnutls:                         ${gnutls_msg}
libzbar:                        ${libzbar_msg}
java:                           ${java_msg}
libidn:                         ${libidn1_msg}${libidn2_msg}
libopus:                        ${libopus_msg}
gstreamer:                      ${gstreamer_msg}
libpulse:                       ${libpulse_msg}
libextractor:                   ${libextractor_msg}
texi2mdoc:                      ${texi2mdoc_msg}
mandoc:                         ${mandoc_msg}
sss:                            ${sss_msg}

GNUnet configuration:
=====================
transports:                     ${transport_msg}
conversation:                   ${conversation_msg}
database backends:              ${features_msg}
experimental:                   ${experimental_msg}

texinfo manual:                 ${texinfo_msg}
transpiled mdocml manual:       ${mdocml_msg}
])

AS_IF([test x$MSG_USER_SETUP != xfalse],
 [AC_MSG_WARN([Please make sure NOW to create a user and group 'gnunet' and additionally a group 'gnunetdns'. Make sure that '/var/lib/gnunet' is owned (and writable) by user 'gnunet'.])
  AS_IF([test x$HAVE_GNUNET_USER != 0],
    [AC_MSG_NOTICE([To do this on this system, run:
# addgroup gnunetdns
# adduser --system --disabled-login --home /var/lib/gnunet gnunet
])])
  AC_MSG_WARN([Each user of GNUnet should be added to the 'gnunet' group.])
  AS_IF([test x$HAVE_GNUNET_USER != 0],
    [AC_MSG_NOTICE([To do this on this system, run:
# adduser USERNAME gnunet
   for each of your users, replacing \"USERNAME\" with the respective login name. Users may have to login again for the changes to take effect.
])])])

AC_MSG_NOTICE([For detailed setup instructions, type 'info gnunet' after the installation or visit https://docs.gnunet.org/])