configure

#!/bin/sh

usage(){
	echo >&2 "Usage: $0 [--use-ps]"
	exit 1
}

trace_tool(){
	ed -s config.h > /dev/null <<!
/TRACE_TOOL .*/s/.*/#define TRACE_TOOL "$1"/
wq
!
}

config(){
	echo "$@" >> config.mk
}

cdeps(){
	"${CC}" -MM $@
}

CC=${CC:-cc}

use_ps=0
for arg in $@
do
	case "$arg" in
		--use-ps)
			use_ps=1
			;;
		*)
			usage
			;;
	esac
done

set -e
rm -f config.mk

arch=`uname -s`

case $arch in
	FreeBSD)
		config "LDFLAGS += -lkvm"
		trace_tool ktrace
		;;
	Linux)
		config "CFLAGS += -D_POSIX_SOURCE -D_BSD_SOURCE"
		trace_tool strace
		;;
	*)
		if test $use_ps -eq 0
		then
			echo "unregonised platform ($arch)" >&2
			echo "Using \`ps\` parser"
			use_ps=1
		fi
		;;
esac

if test $use_ps -ne 0
then config "CFLAGS += -DMACHINE_PS"
fi

try_cflag(){
	if echo 'int main(){}' | "${CC}" "$@" -xc - >/dev/null 2>&1
	then config "CFLAGS += $@"
	fi
}

try_cflag -Wmissing-prototypes
try_cflag -Wmissing-noreturn
try_cflag -Wmissing-variable-declarations
try_cflag -Wshadow
try_cflag -Wshorten-64-to-32
try_cflag -Wunused-macros
try_cflag -Wno-dollar-in-identifier-extension

echo Configured for $arch