#!/bin/sh
# Try and be like autotools configure, but without autotools

echo "configure args: $*"
exec 3>config.log

# Ensure that we do not inherit these from env
OS=
BUILD=
HOST=
HOSTCC=
TARGET=
: ${PREFIX=/usr}
INCLUDEDIR=
DEBUG=
POLL=

for x do
	opt=${x%%=*}
	var=${x#*=}
	case "$opt" in
	--os|OS) OS=$var;;
	--debug) DEBUG=$var;;
	--disable-debug) DEBUG=no;;
	--enable-debug) DEBUG=yes;;
	--prefix) PREFIX=$var;;
	--sysconfdir) SYSCONFDIR=$var;;
	--bindir|--sbindir) SBINDIR=$var;;
	--libexecdir) LIBEXECDIR=$var;;
	--statedir|--localstatedir) STATEDIR=$var;;
	--dbdir) DBDIR=$var;;
	--rundir|--runstatedir) RUNDIR=$var;;
	--mandir) MANDIR=$var;;
	--datadir) DATADIR=$var;;
	--with-ccopts|CFLAGS) CFLAGS=$var;;
	-I|--includedir) INCLUDEDIR="$INCLUDEDIR${INCLUDEDIR:+ }-I$var";;
	CC) CC=$var;;
	CPPFLAGS) CPPFLAGS=$var;;
	PKG_CONFIG) PKG_CONFIG=$var;;
	--with-hook) HOOKSCRIPTS="$HOOKSCRIPTS${HOOKSCRIPTS:+ }$var";;
	--with-hooks|HOOKSCRIPTS) HOOKSCRIPTS=$var; HOOKSET=true;;
	--build) BUILD=$var;;
	--host) HOST=$var; HOSTCC=$var-;;
	--target) TARGET=$var;;
	--libdir) LIBDIR=$var;;
	--with-poll) POLL="$var";;
	--infodir) ;; # ignore autotools
	--disable-maintainer-mode|--disable-dependency-tracking) ;;
	--disable-silent-rules) ;;
	-V|--version)
		v=$(sed -ne 's/.*VERSION[[:space:]]*"\([^"]*\).*/\1/p' src/parpd.h);
		c=$(sed -ne 's/^.*copyright\[\] = "\([^"]*\).*/\1/p' src/parpd.c);
		echo "parpd-$v $c";
		exit 0;;
	-h|--help) cat <<EOF
\`configure' configures this package to adapt to many kinds of systems.

Usage: configure [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

Configuration:
  -h, --help              display this help and exit
      --help=short        display options specific to this package
  -V, --version           display version information and exit

Installation directories:
  --prefix=PREFIX         install architecture-independent files in PREFIX [/]

By default, \`make install' will install all the files in \'/sbin',
\`/libexec', etc. You can specify
an installation prefix other than \`/' using \`--prefix',
for instance \`--prefix=$HOME'.

For better control, use the options below.

Fine tuning of the installation directories:
  --bindir=DIR            user executables [PREFIX/bin]
  --sbindir=DIR           system admin executables [PREFIX/sbin]
  --libexecdir=DIR        program executables [PREFIX/libexec]
  --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
  --localstatedir=DIR     modifiable single-machine data [/var]
  --libdir=DIR            object code libraries [PREFIX/lib]
  --includedir=DIR        C header files [PREFIX/include]
  --mandir=DIR            man documentation [PREFIX/man]

System types:
  --build=BUILD           configure for building on BUILD [guessed]
  --host=HOST       build programs to run on HOST [BUILD]
  --target=TARGET   configure for building compilers for TARGET [HOST]

Optional Features:
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]

Some influential environment variables:
  CC          C compiler command
  CFLAGS      C compiler flags
  LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a
              nonstandard directory <lib dir>
  CPPFLAGS    C/C++ preprocessor flags, e.g. -I<include dir> if you have
              headers in a nonstandard directory <include dir>
  CPP         C preprocessor
  PKG_CONFIG  pkg-config executable

Use these variables to override the choices made by \`configure' or to help
it to find libraries and programs with nonstandard names/locations.
EOF
exit 0
;;
	*) echo "$0: WARNING: unknown option $opt" >&2;;
	esac
done

: ${SED:=sed}
: ${GREP:=grep}
: ${PKG_CONFIG:=pkg-config}
: ${WC:=wc}

_which()
{
	x="$(which "$1" 2>/dev/null)"
	if [ $? = 0 -a -n "$x" ]; then
		echo "$x"
		return 0
	fi
	for x in /sbin/"$1" /usr/sbin/"$1" \
		/usr/pkg/sbin/"$1" /usr/local/sbin/"$1"
	do
		if [ -e "$x" ]; then
			echo "$x"
			return 0
		fi
	done
	return 1
}

CONFIG_H=config.h
CONFIG_MK=config.mk

if [ -z "$BUILD" ]; then
	# autoconf target triplet: cpu-vendor-os
	BUILD=$(uname -m)-unknown-$(uname -s | tr '[:upper:]' '[:lower:]')
fi
: ${HOST:=$BUILD}

if [ -z "$OS" ]; then
	echo "Deriving operating system from ... $HOST"
	# Derive OS from cpu-vendor-[kernel-]os
	CPU=${HOST%%-*}
	REST=${HOST#*-}
	if [ "$CPU" != "$REST" ]; then
		VENDOR=${REST%%-*}
		REST=${REST#*-}
		if [ "$VENDOR" != "$REST" ]; then
			# Use kernel if given, otherwise os
			OS=${REST%%-*}
		else
			# 2 tupple
			OS=$VENDOR
			VENDOR=
		fi
	fi

        # Work with cpu-kernel-os, ie Debian
	case "$VENDOR" in
	linux*|kfreebsd*) OS=$VENDOR; VENDOR= ;;
	esac
	case "$REST" in
	gnu/kfreebsd*)		OS="kfreebsd"; VENDOR= ;;
	esac
	# Special case
	case "$OS" in
	dragonfly*)
		# This means /usr HAS to be mounted not via dhcpcd
		: ${LIBEXECDIR:=${PREFIX:-/usr}/libexec}
		;;
	gnu*) OS=hurd;; # No HURD support as yet
	esac
fi

echo "Configuring parpd for ... $OS"
rm -f $CONFIG_H $CONFIG_MK
echo "# $OS" >$CONFIG_MK
echo "/* $OS */" >$CONFIG_H

if [ "$PREFIX" = /usr ]; then
	: ${SYSCONFDIR:=/etc}
else
	: ${SYSCONFDIR:=$PREFIX/etc}
fi
: ${SBINDIR:=$PREFIX/sbin}
: ${STATEDIR:=/var}
: ${RUNDIR:=$STATEDIR/run}
: ${MANDIR:=${PREFIX:-/usr}/share/man}

eval SYSCONFDIR="$SYSCONFDIR"
eval SBINDIR="$SBINDIR"
eval RUNDIR="$RUNDIR"
eval MANDIR="$MANDIR"

echo "#ifndef	SYSCONFDIR" >>$CONFIG_H
for x in SYSCONFDIR SBINDIR RUNDIR; do
	eval v=\$$x
	# Make files look nice for import
	l=$((10 - ${#x}))
	unset t
	[ $l -gt 3 ] && t="	"
	echo "$x=$t	$v" >>$CONFIG_MK
	unset t
	[ $l -gt 2 ] && t="	"
	echo "#define	$x$t		\"$v\"" >>$CONFIG_H
done
echo "#endif" >>$CONFIG_H

echo "MANDIR=		$MANDIR" >>$CONFIG_MK

# Always obey CC.
if [ -n "$CC" ]; then
	HOSTCC=
else
	CC=cc
	_COMPILERS="cc clang gcc pcc icc"
fi
# Only look for a cross compiler if --host and --build are not the same
if [ -n "$HOSTCC" -a "$BUILD" != "$HOST" ]; then
	for _CC in $_COMPILERS; do
		_CC=$(_which "$HOSTCC$_CC")
		if [ -x "$_CC" ]; then
			CC=$_CC
			break
		fi
	done
fi
if ! type "$CC" >/dev/null 2>&1; then
	for _CC in $_COMPILERS; do
		_CC=$(_which "$_CC")
		if [ -x "$_CC" ]; then
			CC=$_CC
			break
		fi
	done
fi

# Set to blank, then append user config
# We do this so our SED call to append to XCC remains portable
if [ -n "$CFLAGS" ]; then
	echo "CFLAGS=" >>$CONFIG_MK
	echo "CFLAGS+=	$CFLAGS" >>$CONFIG_MK
fi
if [ -n "$CPPFLAGS" ]; then
	echo "CPPFLAGS=" >>$CONFIG_MK
	echo "CPPFLAGS+=	$CPPFLAGS" >>$CONFIG_MK
fi
if [ -n "$INCLUDEDIR" ]; then
	echo "CPPFLAGS+=	$INCLUDEDIR" >>$CONFIG_MK
fi
if [ -n "$LDFLAGS" ]; then
	echo "LDFLAGS=" >>$CONFIG_MK
	echo "LDFLAGS+=	$LDFLAGS" >>$CONFIG_MK
fi

echo "CPPFLAGS+=	-DHAVE_CONFIG_H" >>$CONFIG_MK

if [ "$STATIC" = yes ]; then
	echo "LDFLAGS+=	-static" >>$CONFIG_MK
fi

if [ -z "$DEBUG" -a -d .git ]; then
	printf "Found git checkout ... "
	DEBUG=yes
fi
if [ -n "$DEBUG" -a "$DEBUG" != no -a "$DEBUG" != false ]; then
	echo "Adding debugging CFLAGS"
	cat <<EOF >>$CONFIG_MK
CPPFLAGS+=	-DSANITIZE_MEMORY
CFLAGS+=	-g -Wall -Wextra
CFLAGS+=	-Wmissing-prototypes -Wmissing-declarations
CFLAGS+=	-Wmissing-format-attribute -Wnested-externs
CFLAGS+=	-Winline -Wcast-align -Wcast-qual -Wpointer-arith
CFLAGS+=	-Wreturn-type -Wswitch -Wshadow
CFLAGS+=	-Wcast-qual -Wwrite-strings
CFLAGS+=	-Wformat=2
CFLAGS+=	-Wpointer-sign -Wmissing-noreturn
EOF
	case "$OS" in
	mirbsd*|openbsd*);; # OpenBSD has many redundant decs in system headers
	bitrig*|solaris*|sunos*)
			echo "CFLAGS+=	-Wredundant-decls" >>$CONFIG_MK
			;; # Bitrig spouts many conversion errors with htons
			   # sunos has many as well
	*)		echo "CFLAGS+=	-Wredundant-decls" >>$CONFIG_MK
			echo "CFLAGS+=	-Wconversion" >>$CONFIG_MK
			;;
	esac

	case "$OS" in
	solaris*|sunos*);;
	*)		echo "CFLAGS+=	-Wstrict-overflow" >>$CONFIG_MK;;
	esac

	# Turn on extra per compiler debugging
	case "$CC" in
	*gcc*)		echo "CFLAGS+=	-Wlogical-op" >>$CONFIG_MK;;
	esac
else
	echo "CPPFLAGS+=	-DNDEBUG" >>$CONFIG_MK
fi

case "$OS" in
linux*)
	echo "SRC_PF=		lpf.c" >>$CONFIG_MK
	;;
*)
	echo "SRC_PF=		bpf.c" >>$CONFIG_MK
	;;
esac

echo "Using compiler .. $CC"
# Add CPPFLAGS and CFLAGS to CC for testing features
XCC="$CC `$SED -n -e 's/CPPFLAGS+=*\(.*\)/\1/p' $CONFIG_MK`"
XCC="$XCC `$SED -n -e 's/CFLAGS+=*\(.*\)/\1/p' $CONFIG_MK`"

# When running tests, treat all warnings as errors.
# This avoids the situation where we link to a libc symbol
# without the correct header because it might be hidden behind
# a _*_SOURCE #define guard.
XCC="$XCC -Wall -Werror"

# Now test we can use the compiler with our CFLAGS
cat <<EOF >_test.c
int main(void) {
	return 0;
}
EOF
_CC=false
if $XCC _test.c -o _test >/dev/null 2>&3; then
	[ -x _test ] && _CC=true
fi
rm -f _test.c _test
if ! $_CC; then
	echo "$CC does not create executables" >&2
	exit 1
fi
[ "$CC" != cc ] && echo "CC=		$CC" >>$CONFIG_MK
$CC --version | $SED -e '1!d'

abort=false
# We require the libc to support non standard functions, like getifaddrs
printf "Testing for getifaddrs ... "
cat <<EOF >_getifaddrs.c
#include <sys/types.h>
#include <ifaddrs.h>
int main(void) {
	struct ifaddrs *ifap;
	return getifaddrs(&ifap);
}
EOF
LIBSOCKET=
if $XCC _getifaddrs.c -o _getifaddrs 2>&3; then
	echo "yes"
elif $XCC _getifaddrs.c -o _getifaddrs -lsocket 2>&3; then
	LIBSOCKET=-lsocket
	echo "yes (-lsocket)"
	echo "LDADD+=		-lsocket" >>$CONFIG_MK
else
	echo "no"
	echo "libc support for getifaddrs is required - aborting" >&2
	abort=true
fi
rm -f _getifaddrs.c _getifaddrs
$abort && exit 1

printf "Testing for clock_gettime ... "
cat <<EOF >_clock_gettime.c
#include <time.h>
int main(void) {
	struct timespec ts;
	return clock_gettime(CLOCK_MONOTONIC, &ts);
}
EOF
if $XCC _clock_gettime.c -o _clock_gettime 2>&3; then
	echo "yes"
elif $XCC _clock_gettime.c -lrt -o _clock_gettime 2>&3; then
	echo "yes (-lrt)"
	echo "LDADD+=		-lrt" >>$CONFIG_MK
else
	echo "no"
	echo "libc support for clock_getttime is required - aborting" >&2
	abort=true
fi
rm -f _clock_gettime.c _clock_gettime
$abort && exit 1

printf "Testing for inet_ntoa ... "
cat <<EOF >_inet_ntoa.c
#include <netinet/in.h>
#include <arpa/inet.h>
int main(void) {
	struct in_addr in = { .s_addr = 0 };
	inet_ntoa(in);
	return 0;
}
EOF
if $XCC _inet_ntoa.c -o _inet_ntoa 2>&3; then
	echo "yes"
elif $XCC _inet_ntoa.c -lnsl -o _inet_ntoa 2>&3; then
	echo "yes (-lnsl)"
	echo "LDADD+=		-lnsl" >>$CONFIG_MK
elif $XCC _inet_ntoa.c -lsocket -o _inet_ntoa 2>&3; then
	echo "yes (-lsocket)"
	echo "LDADD+=		-lsocket" >>$CONFIG_MK	
else
	echo "no"
	echo "libc support for inet_ntoa is required - aborting" >&2
	abort=true
fi
rm -f _inet_ntoa.c _inet_ntoa
$abort && exit 1

if [ -z "$STRLCPY" ]; then
	printf "Testing for strlcpy ... "
	cat <<EOF >_strlcpy.c
#include <string.h>
int main(void) {
	const char s1[] = "foo";
	char s2[10];
	strlcpy(s2, s1, sizeof(s2));
	return 0;
}
EOF
	if $XCC _strlcpy.c -o _strlcpy 2>&3; then
		STRLCPY=yes
	else
		STRLCPY=no
	fi
	echo "$STRLCPY"
	rm -f _strlcpy.c _strlcpy
fi
if [ "$STRLCPY" = no ]; then
	echo "COMPAT_SRCS+=	compat/strlcpy.c" >>$CONFIG_MK
	echo "#include			\"compat/strlcpy.h\"" >>$CONFIG_H
fi

if [ -z "$TAILQ_FOREACH_SAFE" ]; then
	printf "Testing for TAILQ_FOREACH_SAFE ... "
	cat <<EOF >_queue.c
#include <sys/queue.h>
int main(void) {
#ifndef TAILQ_FOREACH_SAFE
#error TAILQ_FOREACH_SAFE
#endif
	return 0;
}
EOF
	if $XCC _queue.c -o _queue 2>&3; then
		TAILQ_FOREACH_SAFE=yes
		TAILQ_FOREACH=yes
	else
		TAILQ_FOREACH_SAFE=no
	fi
	echo "$TAILQ_FOREACH_SAFE"
	rm -f _queue.c _queue
fi
if [ "$TAILQ_FOREACH_SAFE" = no ] && [ -z "$TAILQ_FOREACH_MUTABLE" ]; then
	printf "Testing for TAILQ_FOREACH_MUTABLE ... "
	cat <<EOF >_queue.c
#include <sys/queue.h>
int main(void) {
#ifndef TAILQ_FOREACH_MUTABLE
#error TAILQ_FOREACH_MUTABLE
#endif
	return 0;
}
EOF
	if $XCC _queue.c -o _queue 2>&3; then
		TAILQ_FOREACH_MUTABLE=yes
		TAILQ_FOREACH_SAFE=yes
		TAILQ_FOREACH=yes
		echo "#define	TAILQ_FOREACH_SAFE	TAILQ_FOREACH_MUTABLE" \
			>> $CONFIG_H
	else
		TAILQ_FOREACH_MUTABLE=no
	fi
	echo "$TAILQ_FOREACH_MUTABLE"
	rm -f _queue.c _queue
fi

if [ -z "$TAILQ_FOREACH" ]; then
	printf "Testing for TAILQ_FOREACH ... "
	cat <<EOF >_queue.c
#include <sys/queue.h>
int main(void) {
#ifndef TAILQ_FOREACH
#error TAILQ_FOREACH
#endif
	return 0;
}
EOF
	if $XCC _queue.c -o _queue 2>&3; then
		TAILQ_FOREACH=yes
	else
		TAILQ_FOREACH=no
	fi
	echo "$TAILQ_FOREACH"
	rm -f _queue.c _queue
fi
if [ "$TAILQ_FOREACH_SAFE" = no ]; then
	# If we don't include sys/queue.h then clang analyser finds
	# too many false positives.
	# See http://llvm.org/bugs/show_bug.cgi?id=18222
	# Strictly speaking this isn't needed, but I like it to help
	# catch any nasties.
	if [ "$TAILQ_FOREACH" = yes ]; then
		echo "#include			<sys/queue.h>">>$CONFIG_H
	fi
	echo "#include			\"compat/queue.h\"">>$CONFIG_H
else
	echo "#define	HAVE_SYS_QUEUE_H" >>$CONFIG_H
fi

if [ -z "$POLL" ]; then
	printf "Testing for kqueue1 ... "
	cat <<EOF >_kqueue.c
#include <sys/types.h>
#include <sys/event.h>
int main(void) {
	return kqueue1(0);
}
EOF
	if $XCC _kqueue.c -o _kqueue 2>&3; then
		POLL=kqueue1
 		echo "yes"
 	else
 		echo "no"
 	fi
	rm -f _kqueue.c _kqueue
fi
if [ -z "$POLL" ]; then
	printf "Testing for kqueue ... "
	cat <<EOF >_kqueue.c
#include <sys/types.h>
#include <sys/event.h>
int main(void) {
	return kqueue();
}
EOF
	if $XCC _kqueue.c -o _kqueue 2>&3; then
		POLL=kqueue
 		echo "yes"
 	else
 		echo "no"
 	fi
	rm -f _kqueue.c _kqueue
fi
if [ -z "$POLL" ]; then
	printf "Testing for epoll ... "
	cat <<EOF >_epoll.c
#ifdef __linux__
#include <linux/version.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 37)
#error kernel has buggy epoll_wait timeout
#endif
#endif

#include <sys/epoll.h>
#include <unistd.h>
int main(void) {
	epoll_create1(EPOLL_CLOEXEC);
	epoll_pwait(-1, NULL, 0, 0, NULL);
	return 0;
}
EOF
	if $XCC _epoll.c -o _epoll 2>&3; then
		POLL=epoll
		echo "#define	HAVE_EPOLL" >>$CONFIG_MK
		echo "yes"
	else
		echo "no"
	fi
	rm -f _epoll.c _epoll
fi
if [ -z "$POLL" ]; then
	printf "Testing for pselect ... "
	cat <<EOF >_pselect.c
#include <sys/select.h>
#include <stdlib.h>
int main(void) {
	pselect(0, NULL, NULL, NULL, NULL, NULL);
	return 0;
}
EOF
	if $XCC _pselect.c -o _pselect 2>&3; then
		POLL=pselect
		echo "yes"
	else
		echo "no"
	fi
	rm -f _pselect.c _pselect
fi
case "$POLL" in
kqueue1)
	echo "#define	HAVE_KQUEUE" >>$CONFIG_H
	echo "#define	HAVE_KQUEUE1" >>$CONFIG_H
	;;
kqueue)
	echo "#define	HAVE_KQUEUE" >>$CONFIG_H
	;;
epoll)
	echo "#define	HAVE_EPOLL" >>$CONFIG_H
	;;
pollts)
	echo "#define	HAVE_POLLTS" >>$CONFIG_H
	;;
ppoll)
	echo "#define	HAVE_PPOLL" >>$CONFIG_H
	;;
pselect)
	echo "#define	HAVE_PSELECT" >>$CONFIG_H
	;;
*)
	echo "No suitable polling function is available, not even pselect" >&2
	exit 1
	;;
esac

echo
echo "   SYSCONFDIR =		$SYSCONFDIR"
echo "   SBINDIR =		$SBINDIR"
echo "   RUNDIR =		$RUNDIR"	
echo "   MANDIR =		$MANDIR"
echo

rm -f parpd
