dnl
dnl Copyright (c) 2004, Stefan Walter
dnl All rights reserved.
dnl
dnl Redistribution and use in source and binary forms, with or without
dnl modification, are permitted provided that the following conditions
dnl are met:
dnl
dnl     * Redistributions of source code must retain the above
dnl       copyright notice, this list of conditions and the
dnl       following disclaimer.
dnl     * Redistributions in binary form must reproduce the
dnl       above copyright notice, this list of conditions and
dnl       the following disclaimer in the documentation and/or
dnl       other materials provided with the distribution.
dnl     * The names of contributors to this software may not be
dnl       used to endorse or promote products derived from this
dnl       software without specific prior written permission.
dnl
dnl THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
dnl "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
dnl LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
dnl FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
dnl COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
dnl INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
dnl BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
dnl OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
dnl AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
dnl OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
dnl THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
dnl DAMAGE.


dnl Process this file with autoconf to produce a configure script.
AC_INIT(proxsmtp, 1.10, stef@thewalter.net)
AM_INIT_AUTOMAKE(proxsmtp, 1.10)

LDFLAGS="$LDFLAGS -L/usr/local/lib"
CFLAGS="$CFLAGS -I/usr/local/include"

AC_CONFIG_SRCDIR([src/proxsmtpd.c])
AM_CONFIG_HEADER([config.h])

# Checks for programs.
AC_PROG_CC
AM_PROG_CC_C_O
AC_PROG_INSTALL
AC_PROG_LN_S
AC_PROG_MAKE_SET

# TODO: Figure out why we need this wierd hack
ACX_PTHREAD( , [echo "ERROR: Pthread support not found."; exit 1] )

LIBS="$PTHREAD_LIBS $LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS -D_POSIX_PTHREAD_SEMANTICS"

AC_MSG_CHECKING([whether running on linux])
case "$host" in
*-*-linux-*)
	platform_linux=yes
	;;
*)
	platform_linux=no
	;;
esac
AC_MSG_RESULT([$platform_linux])

# Some checks for Solaris
AC_CHECK_LIB(socket, getsockname)
AC_CHECK_LIB(nsl, getaddrinfo)

# Checks for header files.
AC_HEADER_STDC
AC_CHECK_HEADERS([limits.h err.h paths.h],,)
AC_CHECK_HEADERS([unistd.h stdio.h stddef.h fcntl.h stdlib.h assert.h errno.h stdarg.h string.h netdb.h], ,
	[echo "ERROR: Required C header missing"; exit 1])

# Check for linux type transparent proxy support
AC_CHECK_HEADERS([linux/types.h linux/netfilter_ipv4.h],
	AC_DEFINE(LINUX_NETFILTER, 1, [Whether the system supports a linux type transparent proxy]),
	[test "$platform_linux" = "yes" && echo "ERROR: Required linux header missing" && exit 1],
	[[
	#ifdef HAVE_LIMITS_H
	#include <limits.h>
	#endif
	#include <sys/socket.h>
	#include <netinet/in.h>
	]]
)

# Check for OpenBSD type transparent proxy support
AC_CHECK_HEADERS([net/pfvar.h],
	AC_DEFINE(USE_PF_NATLOOKUP, 1, [Whether the system supports OpenBSD packet filter for transparent proxy]),,)

# Checks for typedefs, structures, and compiler characteristics.
AC_TYPE_SIZE_T

# We use error checking mutexes whenever possible
AC_CHECK_DECL(PTHREAD_MUTEX_ERRORCHECK_NP, [AC_DEFINE(HAVE_ERR_MUTEX, 1, "Error Mutex Type")],
	[AC_CHECK_DECL(PTHREAD_MUTEX_ERRORCHECK, [AC_DEFINE(HAVE_ERR_MUTEX, 2)], ,
	[ #include <pthread.h> ])], [ #include <pthread.h> ])

# Required Variables
AC_CHECK_MEMBER(struct tm.tm_gmtoff,
    [AC_DEFINE(HAVE_TM_GMTOFF, 1, "Time Zone GMT Offset")],
    ,[ #include <time.h> ])
AC_CHECK_GLOBAL(__argv)

# Required Functions
AC_CHECK_FUNCS([memset strerror malloc realloc getopt strchr tolower getaddrinfo usleep], ,
	       [echo "ERROR: Required function missing"; exit 1])
AC_CHECK_FUNCS([strlwr strlcat strlcpy strncat strncpy strcasestr setenv daemon])
AC_CHECK_FUNCS([getline getdelim])

# --------------------------------------------------------------------
# Linux tproxy support
AC_ARG_ENABLE(tproxy,
	AC_HELP_STRING([--enable-tproxy], [Enable linux true transparent proxy]))

# We default to enable if linux
if test "$enable_tproxy" = ""; then
	enable_tproxy="$platform_linux"
fi

if test "$enable_tproxy" = "yes"; then
	AC_CHECK_DECL(IP_TRANSPARENT,
		[have_tproxy="yes"],
		[have_tproxy="no"],
		[[
		#include <sys/socket.h>
		#include <netinet/in.h>
		]]
	)

	if test "$have_tproxy" = "yes"; then
		AC_DEFINE(HAVE_IP_TRANSPARENT, 1, [Linux transparent proxy])

	else
		AC_MSG_CHECKING([whether broken IP_TRANSPARENT definition is present])
		AC_COMPILE_IFELSE([[
			#include <sys/socket.h>
			#include <linux/in.h>
			int main (void) { return IP_TRANSPARENT == 19; }
		]], [have_tproxy="yes"], [have_tproxy="no"])
		AC_MSG_RESULT([$have_tproxy])

		if test "$have_tproxy" = "yes"; then
			AC_DEFINE(HAVE_IP_TRANSPARENT, 1, [Linux transparent proxy])
			AC_DEFINE(IP_TRANSPARENT, 19, [Fix missing linux header definition])
		else
			AC_MSG_ERROR([Only linux 2.6.28 and later support true transparent proxy. See --disable-tproxy])
		fi
	fi
fi

# --------------------------------------------------------------------
# Capabilities support

AC_ARG_ENABLE(capabilities,
	AC_HELP_STRING([--enable-capabilities], [Enable linux capabilities support]))

# We default to enable if linux
if test "$enable_capabilities" = ""; then
	enable_capabilities="$platform_linux"
fi

if test "$enable_capabilities" = "yes"; then
	AC_CHECK_LIB([cap], [cap_get_proc], have_libcap="yes", have_libcap="no")
	if test "$have_libcap" = "yes"; then
		AC_DEFINE(HAVE_LIBCAP, 1, [Have libcap2 package, libcap library])
		LIBS="$LIBS -lcap"
	else
		AC_MSG_ERROR([Could not find the libcap2 libraries. See --disable-capabilities])
	fi
fi

# --------------------------------------------------------------------
# Debug Mode

# Debug mode
AC_ARG_ENABLE(debug,
	    AC_HELP_STRING([--enable-debug],
	    [Compile binaries in debug mode]))

if test "$enable_debug" = "yes"; then
	CFLAGS="$CFLAGS -g -O0 -Wall"
	AC_DEFINE_UNQUOTED(_DEBUG, 1, [In debug mode])
	echo "enabling debug compile mode"
else
	enable_debug="no"
fi

# --------------------------------------------------------------------
# Strict Mode

# Strict mode
AC_ARG_ENABLE(strict,
	    AC_HELP_STRING([--enable-strict],
	    [Compile with all warnings strictly enabled]))

if test "$enable_strict" = "yes"; then
	CFLAGS="$CFLAGS -Wall -Werror"
	echo "enabling strict compile mode"
else
	enable_strict="no"
fi

# --------------------------------------------------------------------

# Have to resolve this for the path below
if test "${prefix}" = "NONE"; then
	prefix=$ac_default_prefix
fi

AC_DEFINE_UNQUOTED(CONF_PREFIX, "`eval echo ${sysconfdir}`", [Installation Prefix] )

AC_CONFIG_FILES([Makefile src/Makefile doc/Makefile])
AC_OUTPUT

# --------------------------------------------------------------------
# Summary

echo "
True transparent proxy:   $enable_tproxy	--enable-tproxy
Capabalities:             $enable_capabilities	--enable-capabilities, libcap2
Debug Mode:               $enable_debug	--enable-debug
Strict Mode:              $enable_strict	--enable-strict
"