#!/bin/sh

set -eu

trap config_failure 1 2 EXIT

usage()
{
	cat "$mb_project_dir"/config.usage

	if [ _$mb_use_custom_cfgdefs = _yes ]; then
		printf '\n\n%s%s\n' \
			" ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" \
			"^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"

		printf '%s%s\n' \
			"| Listed above are configure's common switches " \
			"and environment variables.     |"

		printf '%s%s\n' \
			"| Found below are project-specific variables " \
			"and other customization options. |"

		printf '%s%s\n\n\n' \
			" ___________________________________________" \
			"__________________________________"

		cat "$mb_project_dir"/project/config/cfgdefs.usage
	fi

	exit 0
}

error_msg()
{
	echo "$@" >&2
}

warning_msg()
{
	echo "$@" >&2
}


init_vars()
{
	mb_project_dir=$(cd "$(dirname $0)" ; pwd)
	mb_pwd=$(pwd)

	mb_custom_cfgdefs_args=''
	mb_custom_cfgdefs_space=''

	mb_vars=$(cat $mb_project_dir/sofort/config.vars | grep -v '^#')

	for mb_var in $mb_vars; do
		mb_expr=$mb_var='${'$mb_var':-}'
		eval "$mb_expr"
	done

	if [ -z "$mb_config" ]; then
		. $mb_project_dir/config.project
	else
		. "$mb_config"
	fi

	# project-specific config definitions
	if [ _$mb_use_custom_cfgdefs = _yes ]; then
		cat $mb_project_dir/sofort/cfgdefs.in \
			> cfgdefs.mk
	else
		printf '%s %s\n\n' \
				'# this project does not include' \
				'a custom config step.'           \
			> cfgdefs.mk
		cat $mb_project_dir/sofort/cfgdefs.in >> cfgdefs.mk
	fi

	# user build-time overrides
	touch usrdefs.mk

	# project
	mb_nickname=$NICKNAME
	mb_source_dir=$SOURCE_DIR

	# dirs
	mb_prefix=$PREFIX
	mb_exec_prefix=$EXEC_PREFIX
	mb_bindir=$BINDIR
	mb_sbindir=$SBINDIR
	mb_libdir=$LIBDIR
	mb_includedir=$INCLUDEDIR
	mb_oldincludedir=$OLDINCLUDEDIR
	mb_mandir=$MANDIR
	mb_docdir=$DOCDIR
	mb_libexecdir=$LIBEXECDIR

	mb_sysconfdir=$SYSCONFDIR
	mb_sharedstatedir=$SHAREDSTATEDIR
	mb_localstatedir=$LOCALSTATEDIR
	mb_runstatedir=$RUNSTATEDIR
	mb_datarootdir=$DATAROOTDIR
	mb_datadir=$DATADIR
	mb_infodir=$INFODIR
	mb_localedir=$LOCALEDIR
	mb_htmldir=$HTMLDIR
	mb_dvidir=$DVIDIR
	mb_pdfdir=$PDFDIR
	mb_psdir=$PSDIR


	# build
	mb_build=$BUILD
	mb_host=$HOST
	mb_cchost=$CCHOST
	mb_cfghost=$CFGHOST
	mb_target=$TARGET
	mb_arch=$ARCH
	mb_compiler=$COMPILER
	mb_toolchain=$TOOLCHAIN
	mb_sysroot=$SYSROOT
	mb_cross_compile=$CROSS_COMPILE
	mb_shell=$SHELL

	# switches
	mb_cflags=$CFLAGS
	mb_cflags_debug=$CFLAGS_DEBUG
	mb_cflags_common=$CFLAGS_COMMON
	mb_cflags_cmdline=$CFLAGS_CMDLINE
	mb_cflags_config=$CFLAGS_CONFIG
	mb_cflags_sysroot=$CFLAGS_SYSROOT
	mb_cflags_os=$CFLAGS_OS
	mb_cflags_site=$CFLAGS_SITE
	mb_cflags_path=$CFLAGS_PATH
	mb_cflags_strict=$CFLAGS_STRICT
	mb_cflags_util=$CFLAGS_UTIL
	mb_cflags_last=$CFLAGS_LAST
	mb_cflags_once=$CFLAGS_ONCE

	mb_ldflags=$LDFLAGS
	mb_ldflags_debug=$LDFLAGS_DEBUG
	mb_ldflags_common=$LDFLAGS_COMMON
	mb_ldflags_cmdline=$LDFLAGS_CMDLINE
	mb_ldflags_config=$LDFLAGS_CONFIG
	mb_ldflags_sysroot=$LDFLAGS_SYSROOT
	mb_ldflags_path=$LDFLAGS_PATH
	mb_ldflags_strict=$LDFLAGS_STRICT
	mb_ldflags_util=$LDFLAGS_UTIL
	mb_ldflags_last=$LDFLAGS_LAST
	mb_ldflags_once=$LDFLAGS_ONCE

	mb_pe_subsystem=$PE_SUBSYSTEM
	mb_pe_image_base=$PE_IMAGE_BASE
	mb_pe_config_defs=$PE_CONFIG_DEFS

	mb_elf_eh_frame=$ELF_EH_FRAME
	mb_elf_hash_style=$ELF_HASH_STYLE
	mb_elf_config_defs=$ELF_CONFIG_DEFS

	# overrides
	mb_native_cc=$NATIVE_CC
	mb_native_cc_host=$NATIVE_CC_HOST
	mb_native_cc_cfghost=$NATIVE_CC_CFGHOST
	mb_native_cc_cflags=$NATIVE_CC_CFLAGS
	mb_native_cc_ldflags=$NATIVE_CC_LDFLAGS

	mb_native_os=$NATIVE_OS
	mb_native_os_bits=$NATIVE_OS_BITS
	mb_native_os_underscore=$NATIVE_OS_UNDERSCORE

	mb_user_cc=$CC
	mb_user_cpp=$CPP
	mb_user_cxx=$CXX
}


verify_build_directory()
{
	if [ "$mb_project_dir" = "$mb_pwd" ]; then
		if [ _$mb_require_out_of_tree = _yes ]; then
			error_msg "$mb_package: out-of-tree builds are required."
			error_msg "please invoke configure again from a clean build directory."
			exit 1
		else
			mb_project_dir='.'
		fi
	fi

	rm -f Makefile Makefile.host Makefile.tmp Makefile.failed
}


verify_source_directory()
{
	if [ -z "$mb_source_dir" ]; then
		if [ _$mb_require_source_dir = _yes ]; then
			error_msg "$mb_package: specifying an external source directory is required."
			error_msg "you can set the source directory either via --source-dir=<path>,"
			error_msg "or by setting the SOURCE_DIR variable."
			exit 1
		fi
	fi
}


common_defaults()
{
	# git
	if [ -n "$mb_source_dir" ]; then
		if [ -d "$mb_source_dir/.git" ]; then
			mb_git_reference_index="\$(SOURCE_DIR)/.git/index"
		fi
	elif [ -d "$mb_project_dir/.git" ]; then
		mb_git_reference_index="\$(PROJECT_DIR)/.git/index"
	fi

	# project
	[ -z "$mb_nickname" ] 		&& mb_nickname=$mb_package
	[ -z "$mb_source_dir" ] 	&& mb_source_dir=$mb_project_dir
	[ -z "$mb_avoid_version" ] 	&& mb_avoid_version='no'

	# pkgconfig
	[ -z "$mb_pkgname" ]		&& mb_pkgname="$mb_default_pkgname"
	[ -z "$mb_pkgdesc" ]		&& mb_pkgdesc="$mb_default_pkgdesc"
	[ -z "$mb_pkgusrc" ]		&& mb_pkgusrc="$mb_default_pkgusrc"
	[ -z "$mb_pkgrepo" ]		&& mb_pkgrepo="$mb_default_pkgrepo"
	[ -z "$mb_pkgpsrc" ]		&& mb_pkgpsrc="$mb_default_pkgpsrc"
	[ -z "$mb_pkgdurl" ]		&& mb_pkgdurl="$mb_default_pkgdurl"
	[ -z "$mb_pkgdefs" ]		&& mb_pkgdefs="$mb_default_pkgdefs"
	[ -z "$mb_pkglibs" ]		&& mb_pkglibs="$mb_default_pkglibs"

	# dirs
	[ -z "$mb_prefix" ] 		&& [ -z "$mb_prefix_set" ] \
					&& mb_prefix='/usr/local'

	[ -z "$mb_exec_prefix" ] 	&& [ -z "$mb_exec_prefix_set" ]	\
					&& mb_exec_prefix=$mb_prefix

	[ -z "$mb_bindir" ] 		&& [ -z "$mb_bindir_set" ] \
					&& [ -z "$mb_bindir_basename" ] \
					&& mb_bindir=$mb_exec_prefix/bin

	[ -z "$mb_bindir" ] 		&& [ -z "$mb_bindir_set" ] \
					&& mb_bindir=$mb_exec_prefix/$mb_bindir_basename

	[ -z "$mb_sbindir" ] 		&& mb_sbindir=$mb_exec_prefix/sbin
	[ -z "$mb_libdir" ] 		&& mb_libdir=$mb_exec_prefix/lib
	[ -z "$mb_includedir" ]		&& mb_includedir=$mb_prefix/include
	[ -z "$mb_oldincludedir" ]	&& mb_oldincludedir=$mb_prefix/include
	[ -z "$mb_datarootdir" ] 	&& mb_datarootdir=$mb_prefix/share
	[ -z "$mb_mandir" ] 		&& mb_mandir=$mb_datarootdir/man
	[ -z "$mb_docdir" ] 		&& mb_docdir=$mb_datarootdir/doc
	[ -z "$mb_libexecdir" ]		&& mb_libexecdir=$mb_exec_prefix/libexec

	[ -z "$mb_sysconfdir" ] 	&& mb_sysconfdir=$mb_exec_prefix/etc
	[ -z "$mb_sharedstatedir" ] 	&& mb_sharedstatedir=$mb_prefix/com
	[ -z "$mb_localstatedir" ] 	&& mb_localstatedir=$mb_prefix/var
	[ -z "$mb_runstatedir" ] 	&& mb_runstatedir=$mb_localstatedir/run
	[ -z "$mb_datarootdir" ] 	&& mb_datarootdir=$mb_prefix/share
	[ -z "$mb_datadir" ] 		&& mb_datadir=$mb_datarootdir
	[ -z "$mb_infodir" ] 		&& mb_infodir=$mb_datarootdir/info
	[ -z "$mb_localedir" ] 		&& mb_localedir=$mb_datarootdir/locale
	[ -z "$mb_htmldir" ] 		&& mb_htmldir=$mb_docdir
	[ -z "$mb_dvidir" ] 		&& mb_dvidir=$mb_docdir
	[ -z "$mb_pdfdir" ] 		&& mb_pdfdir=$mb_docdir
	[ -z "$mb_psdir" ] 		&& mb_psdir=$mb_docdir


	# build
	[ -z "$mb_build" ] 		&& mb_build=$mb_default_build
	[ -z "$mb_host" ] 		&& mb_host=$mb_default_host
	[ -z "$mb_cchost" ] 		&& mb_cchost=$mb_default_cchost
	[ -z "$mb_cfghost" ] 		&& mb_cfghost=$mb_default_cfghost
	[ -z "$mb_target" ] 		&& mb_target=$mb_default_target
	[ -z "$mb_arch" ] 		&& mb_arch=$mb_default_arch
	[ -z "$mb_compiler" ] 		&& mb_compiler=$mb_default_compiler
	[ -z "$mb_toolchain" ] 		&& mb_toolchain=$mb_default_toolchain
	[ -z "$mb_sysroot" ] 		&& mb_sysroot=$mb_default_sysroot
	[ -z "$mb_cross_compile" ] 	&& mb_cross_compile=$mb_default_cross_compile
	[ -z "$mb_shell" ] 		&& mb_shell=$mb_default_shell

	# switches
	[ -z "$mb_cflags_debug" ]	&& mb_cflags_debug=$mb_default_cflags_debug
	[ -z "$mb_cflags_common" ]	&& mb_cflags_common=$mb_default_cflags_common
	[ -z "$mb_cflags_cmdline" ]	&& mb_cflags_cmdline=$mb_default_cflags_cmdline
	[ -z "$mb_cflags_config" ]	&& mb_cflags_config=$mb_default_cflags_config
	[ -z "$mb_cflags_sysroot" ]	&& mb_cflags_sysroot=$mb_default_cflags_sysroot
	[ -z "$mb_cflags_os" ]		&& mb_cflags_os=$mb_default_cflags_os
	[ -z "$mb_cflags_site" ]	&& mb_cflags_site=$mb_default_cflags_site
	[ -z "$mb_cflags_path" ]	&& mb_cflags_path=$mb_default_cflags_path
	[ -z "$mb_cflags_strict" ]	&& mb_cflags_strict=$mb_default_cflags_strict
	[ -z "$mb_cflags_util" ]	&& mb_cflags_util=$mb_default_cflags_util
	[ -z "$mb_cflags_last" ]	&& mb_cflags_last=$mb_default_cflags_last
	[ -z "$mb_cflags_once" ]	&& mb_cflags_once=$mb_default_cflags_once

	[ -z "$mb_ldflags_debug" ]	&& mb_ldflags_debug=$mb_default_ldflags_debug
	[ -z "$mb_ldflags_common" ]	&& mb_ldflags_common=$mb_default_ldflags_common
	[ -z "$mb_ldflags_cmdline" ]	&& mb_ldflags_cmdline=$mb_default_ldflags_cmdline
	[ -z "$mb_ldflags_config" ]	&& mb_ldflags_config=$mb_default_ldflags_config
	[ -z "$mb_ldflags_sysroot" ]	&& mb_ldflags_sysroot=$mb_default_ldflags_sysroot
	[ -z "$mb_ldflags_path" ]	&& mb_ldflags_path=$mb_default_ldflags_path
	[ -z "$mb_ldflags_strict" ]	&& mb_ldflags_strict=$mb_default_ldflags_strict
	[ -z "$mb_ldflags_util" ]	&& mb_ldflags_util=$mb_default_ldflags_util
	[ -z "$mb_ldflags_last" ]	&& mb_ldflags_last=$mb_default_ldflags_last
	[ -z "$mb_ldflags_once" ]	&& mb_ldflags_once=$mb_default_ldflags_once

	[ -z "$mb_pe_subsystem" ]	&& mb_pe_subsystem=$mb_default_pe_subsystem
	[ -z "$mb_pe_image_base" ]	&& mb_pe_image_base=$mb_default_pe_image_base
	[ -z "$mb_pe_config_defs" ]	&& mb_pe_config_defs=$mb_default_pe_config_defs

	[ -z "$mb_elf_eh_frame" ]	&& mb_elf_eh_frame=$mb_default_elf_eh_frame
	[ -z "$mb_elf_hash_style" ]	&& mb_elf_hash_style=$mb_default_elf_hash_style
	[ -z "$mb_elf_config_defs" ]	&& mb_elf_config_defs=$mb_default_elf_config_defs

	# config
	[ -z "$mb_all_static" ]		&& mb_all_static='no'
	[ -z "$mb_all_shared" ]		&& mb_all_shared='no'
	[ -z "$mb_disable_frontend" ]	&& mb_disable_frontend='no'
	[ -z "$mb_disable_static" ]	&& mb_disable_static='no'
	[ -z "$mb_disable_shared" ]	&& mb_disable_shared='no'

	# host/target
	[ -z "$mb_host" ] 		&& mb_host=$mb_target
	[ -z "$mb_target" ] 		&& mb_target=$mb_host

	# sysroot
	if [ -n "$mb_sysroot" ]; then
		if [ -z "$mb_cflags_sysroot" ]; then
			mb_cflags_sysroot="--sysroot=$mb_sysroot"
		fi

		if [ -z "$mb_ldflags_sysroot" ]; then
			mb_ldflags_sysroot="--sysroot=$mb_sysroot"
		fi
	fi

	# debug
	if [ _$mb_debug = _yes ]; then
		if [ -z "$mb_cflags_debug" ]; then
			mb_cflags_debug='-g3 -O0'
		fi
	fi

	# toolchain
	if [ -z "$mb_toolchain" ]; then
		mb_toolchain='binutils'
	fi

	# fallback host recipe
	if [ -n "$mb_host" ]; then
		if ! [ -f $mb_project_dir/sysinfo/host/$mb_host.mk ]; then
			if [ -z "$mb_cross_compile" ]; then
				mb_cross_compile=$mb_host-
			fi

			mb_host='any-host';
		fi
	fi

	# fallback compiler recipe
	if [ -n "$mb_compiler" ]; then
		if ! [ -f $mb_project_dir/sysinfo/compiler/$mb_compiler.mk ]; then
			mb_compiler='any-compiler'
		fi
	fi
}


native_defaults()
{
	# CC (when set, must be valid)
	if [ -n "$CC" ]; then
		$CC -dM -E - < /dev/null > /dev/null
	fi

	# compiler
	[ -z "$mb_native_cc" ] && mb_native_cc='cc'
	$mb_native_cc -dM -E - < /dev/null > /dev/null 2>/dev/null || mb_native_cc=

	[ -z "$mb_native_cc" ] && mb_native_cc='gcc'
	$mb_native_cc -dM -E - < /dev/null > /dev/null 2>/dev/null || mb_native_cc=

	[ -z "$mb_native_cc" ] && mb_native_cc='clang'
	$mb_native_cc -dM -E - < /dev/null > /dev/null 2>/dev/null || mb_native_cc=

	[ -z "$mb_native_cc" ] && mb_native_cc='cparser'
	$mb_native_cc -dM -E - < /dev/null > /dev/null 2>/dev/null || mb_native_cc=

	if [ -z "$mb_native_cc" ]; then
		echo "configure: info: could not find a working native compiler."
		mb_native_cc='false'
	fi

	if [ -z "$mb_native_cc_host" ]; then
		mb_native_cc_host=$($mb_native_cc $mb_native_cc_cflags -dumpmachine)
	fi

	if [ -z "$mb_compiler" ]; then
		$mb_native_cc -dM -E - < /dev/null | grep -q '__clang__' && mb_compiler='clang'
	fi

	if [ -z "$mb_compiler" ]; then
		$mb_native_cc -dM -E - < /dev/null | grep -q '__GCC' && mb_compiler='gcc'
	fi

	if [ -z "$mb_compiler" ]; then
		$mb_native_cc -dM -E - < /dev/null | grep -q "^gcc" && mb_compiler='gcc'
	fi

	if [ -z "$mb_compiler" ]; then
		$mb_native_cc -dM -E - < /dev/null | grep -q '__CPARSER__' && mb_compiler='cparser'
	fi

	if [ -z "$mb_compiler" ]; then
		echo "configure: info: could not identify the native compiler."
		mb_compiler='any-compiler'
	fi


	# host
	if [ -z "$mb_host" ]; then
		mb_host='native'
	fi


	# target
	if [ -z "$mb_target" ]; then
		mb_target='native'
	fi


	# os
	if [ -z "$mb_native_os" ]; then
		mb_native_os=$(uname | tr '[:upper:]' '[:lower:]')
	fi

	mb_native_os_sizeof_pointer=$($mb_native_cc -dM -E - < /dev/null \
			| awk '$2 == "__SIZEOF_POINTER__" { print $3 }')

	mb_native_os_bits=$((8 * ${mb_native_os_sizeof_pointer:-0}))

	if [ $mb_native_os_bits = 32 ]; then
		mb_native_os_underscore='_'
	else
		mb_native_os_underscore=''
	fi

	if [ -z "$mb_native_os_sizeof_pointer" ]; then
		warning_msg "config error: could not determine size of pointer on native system."
	fi

	# grumpily support crooked uname output
	if ! [ -f $mb_project_dir/sysinfo/os/$mb_native_os.mk ]; then
		mb_native_os=$(echo $mb_native_os | cut -d'_' -f1)
	fi

	# fallback os recipe
	if ! [ -f $mb_project_dir/sysinfo/os/$mb_native_os.mk ]; then
		mb_native_os='any-os';
	fi
}


cross_defaults()
{
	if [ -z "$mb_cross_compile" ] && [ "$mb_host" != native ]; then
		mb_cross_compile=$mb_host'-'
	fi
}


config_flags()
{
	mb_ldflags_tmp=" $mb_ldflags "
	mb_ldflags_libs=$(echo "$mb_ldflags_tmp" | sed 's/ -static / /g')

	if [ "$mb_ldflags_tmp" != "$mb_ldflags_libs" ]; then
		mb_ldflags="$mb_ldflags_libs"
		mb_ldflags_util="$mb_ldflags_util -static"
	fi

	# ccstrict
	if [ _$mb_ccstrict = _yes ]; then
		mb_cflags_strict='-Wall -Werror -Wextra -Wundef'
	fi

	# ldstrict
	if [ _$mb_ldstrict = _yes ]; then
		mb_ldflags_strict='-Wl,--no-undefined'
	fi
}


config_copy()
{
	sed 		-e 's^@package@^'"$mb_package"'^g' 				\
			-e 's^@nickname@^'"$mb_nickname"'^g'				\
			-e 's^@project_dir@^'"$mb_project_dir"'^g'			\
			-e 's^@source_dir@^'"$mb_source_dir"'^g'			\
			-e 's^@git_reference_index@^'"$mb_git_reference_index"'^g'	\
			-e 's^@custom_install_headers@^'"$mb_custom_install_headers"'^g' \
			-e 's^@avoid_version@^'"$mb_avoid_version"'^g'			\
											\
			-e 's^@pkgname@^'"$mb_pkgname"'^g'				\
			-e 's^@pkgdesc@^'"$mb_pkgdesc"'^g'				\
			-e 's^@pkgusrc@^'"$mb_pkgusrc"'^g'				\
			-e 's^@pkgrepo@^'"$mb_pkgrepo"'^g'				\
			-e 's^@pkgpsrc@^'"$mb_pkgpsrc"'^g'				\
			-e 's^@pkgdurl@^'"$mb_pkgdurl"'^g'				\
			-e 's^@pkgdefs@^'"$mb_pkgdefs"'^g'				\
			-e 's^@pkglibs@^'"$mb_pkglibs"'^g'				\
											\
			-e 's^@build@^'"$mb_build"'^g'					\
			-e 's^@host@^'"$mb_host"'^g'					\
			-e 's^@target@^'"$mb_target"'^g'				\
			-e 's^@arch@^'"$mb_arch"'^g'					\
			-e 's^@compiler@^'"$mb_compiler"'^g'				\
			-e 's^@toolchain@^'"$mb_toolchain"'^g'				\
			-e 's^@sysroot@^'"$mb_sysroot"'^g'				\
			-e 's^@cross_compile@^'"$mb_cross_compile"'^g'			\
			-e 's^@shell@^'"$mb_shell"'^g'					\
											\
			-e 's^@cflags@^'"$mb_cflags"'^g'				\
			-e 's^@cflags_debug@^'"$mb_cflags_debug"'^g'			\
			-e 's^@cflags_common@^'"$mb_cflags_common"'^g'			\
			-e 's^@cflags_cmdline@^'"$mb_cflags $mb_cflags_cmdline"'^g'	\
			-e 's^@cflags_config@^'"$mb_cflags_config"'^g'			\
			-e 's^@cflags_sysroot@^'"$mb_cflags_sysroot"'^g'		\
			-e 's^@cflags_os@^'"$mb_cflags_os"'^g'				\
			-e 's^@cflags_site@^'"$mb_cflags_site"'^g'			\
			-e 's^@cflags_path@^'"$mb_cflags_path"'^g'			\
			-e 's^@cflags_strict@^'"$mb_cflags_strict"'^g'			\
			-e 's^@cflags_util@^'"$mb_cflags_util"'^g'			\
			-e 's^@cflags_last@^'"$mb_cflags_last"'^g'			\
			-e 's^@cflags_once@^'"$mb_cflags_once"'^g'			\
											\
			-e 's^@ldflags@^'"$mb_ldflags"'^g'				\
			-e 's^@ldflags_debug@^'"$mb_ldflags_debug"'^g'			\
			-e 's^@ldflags_common@^'"$mb_ldflags_common"'^g'		\
			-e 's^@ldflags_cmdline@^'"$mb_ldflags $mb_ldflags_cmdline"'^g'	\
			-e 's^@ldflags_config@^'"$mb_ldflags_config"'^g'		\
			-e 's^@ldflags_sysroot@^'"$mb_ldflags_sysroot"'^g'		\
			-e 's^@ldflags_path@^'"$mb_ldflags_path"'^g'			\
			-e 's^@ldflags_strict@^'"$mb_ldflags_strict"'^g'		\
			-e 's^@ldflags_util@^'"$mb_ldflags_util"'^g'			\
			-e 's^@ldflags_last@^'"$mb_ldflags_last"'^g'			\
			-e 's^@ldflags_once@^'"$mb_ldflags_once"'^g'			\
											\
			-e 's^@pe_subsystem@^'"$mb_pe_subsystem"'^g'			\
			-e 's^@pe_image\_base@^'"$mb_pe_image_base"'^g'			\
			-e 's^@pe_config\_defs@^'"$mb_pe_config_defs"'^g'		\
											\
			-e 's^@elf_eh\_frame@^'"$mb_elf_eh_frame"'^g'			\
			-e 's^@elf_hash\_style@^'"$mb_elf_hash_style"'^g'		\
			-e 's^@elf_config\_defs@^'"$mb_elf_config_defs"'^g'		\
											\
			-e 's^@prefix@^'"$mb_prefix"'^g'				\
			-e 's^@exec_prefix@^'"$mb_exec_prefix"'^g'			\
			-e 's^@bindir@^'"$mb_bindir"'^g'				\
			-e 's^@sbindir@^'"$mb_sbindir"'^g'				\
			-e 's^@libdir@^'"$mb_libdir"'^g'				\
			-e 's^@includedir@^'"$mb_includedir"'^g'			\
			-e 's^@oldincludedir@^'"$mb_oldincludedir"'^g'			\
			-e 's^@mandir@^'"$mb_mandir"'^g'				\
			-e 's^@docdir@^'"$mb_docdir"'^g'				\
			-e 's^@libexecdir@^'"$mb_libexecdir"'^g'			\
											\
			-e 's^@sysconfdir@^'"$mb_sysconfdir"'^g'			\
			-e 's^@sharedstatedir@^'"$mb_sharedstatedir"'^g'		\
			-e 's^@localstatedir@^'"$mb_localstatedir"'^g'			\
			-e 's^@runstatedir@^'"$mb_runstatedir"'^g'			\
			-e 's^@datarootdir@^'"$mb_datarootdir"'^g'			\
			-e 's^@datadir@^'"$mb_datadir"'^g'				\
			-e 's^@infodir@^'"$mb_infodir"'^g'				\
			-e 's^@localedir@^'"$mb_localedir"'^g'				\
			-e 's^@htmldir@^'"$mb_htmldir"'^g'				\
			-e 's^@dvidir@^'"$mb_dvidir"'^g'				\
			-e 's^@pdfdir@^'"$mb_pdfdir"'^g'				\
			-e 's^@psdir@^'"$mb_psdir"'^g'					\
											\
			-e 's^@native_cc@^'"$mb_native_cc"'^g'				\
			-e 's^@native_cc_host@^'"$mb_native_cc_host"'^g'		\
			-e 's^@native_cc_cfghost@^'"$mb_native_cc_cfghost"'^g'		\
			-e 's^@native_cc_cflags@^'"$mb_native_cc_cflags"'^g'		\
			-e 's^@native_cc_ldflags@^'"$mb_native_cc_ldflags"'^g'		\
											\
			-e 's^@native_os@^'"$mb_native_os"'^g'				\
			-e 's^@native_os_bits@^'"$mb_native_os_bits"'^g'		\
			-e 's^@native_os_underscore@^'"$mb_native_os_underscore"'^g'	\
											\
			-e 's^@user_cc@^'"$mb_user_cc"'^g'				\
			-e 's^@user_cpp@^'"$mb_user_cpp"'^g'				\
			-e 's^@user_cxx@^'"$mb_user_cxx"'^g'				\
											\
			-e 's^@all_static@^'"$mb_all_static"'^g'			\
			-e 's^@all_shared@^'"$mb_all_shared"'^g'			\
			-e 's^@disable_frontend@^'"$mb_disable_frontend"'^g'		\
			-e 's^@disable_static@^'"$mb_disable_static"'^g'		\
			-e 's^@disable_shared@^'"$mb_disable_shared"'^g'		\
											\
			-e 's^@use_custom_cfgdefs@^'"$mb_use_custom_cfgdefs"'^g'	\
			-e 's^@use_custom_usrdefs@^'"$mb_use_custom_usrdefs"'^g'	\
		$mb_project_dir/Makefile.in > $mb_pwd/Makefile.tmp

	if [ -z "$mb_cchost" ]; then
		if [ "$mb_host" = 'native' ]; then
			if [ -n "$mb_user_cc" ]; then
				mbt_cc="$mb_user_cc"
			else
				mbt_cc="$mb_native_cc"
			fi

			mbt_cflags=$(make -f $mb_pwd/Makefile.tmp .display-cflags)
			mb_cchost=$($mbt_cc $mbt_cflags -dumpmachine)
		else
			mb_cchost=$mb_host
		fi
	fi
}


config_custom()
{
	if [ _$mb_use_custom_cfgdefs = _yes ]; then
		eval . $mb_project_dir/project/config/cfgdefs.sh \
			"$mb_custom_cfgdefs_args"
		config_copy
	fi

	if [ _$mb_use_custom_usrdefs = _yes ]; then
		. $mb_project_dir/project/usrdefs.sh
	fi
}


config_cfghost()
{
	if [ -z "$mb_cfghost" ]; then
		mb_cfghost=$mb_cchost
	fi

	sed		-e 's^@cchost@^'"$mb_cchost"'^g'     \
			-e 's^@cfghost@^'"$mb_cfghost"'^g'   \
		$mb_pwd/Makefile.tmp > $mb_pwd/Makefile.host

	rm  $mb_pwd/Makefile.tmp
	mv  $mb_pwd/Makefile.host $mb_pwd/Makefile
}


config_support()
{
	[ _$mb_disable_shared = _yes ] && return 0

	mbt_cc=$(make .display-cc)
	mbt_cflags=$(make .display-cflags)
	mbt_source='int foo(int x){return ++x;}'
	mbt_result=no

	rm -f a.out
	printf '%s' "$mbt_source" | $mbt_cc -shared -o a.out -xc -
	[ -f a.out ] && mbt_result=yes
	rm -f a.out

	if [ $mbt_result = no ]; then
		mb_disable_shared=yes
		config_copy
	fi
}


config_host()
{
	make -s host.tag && return 0

	error_msg "configure was able to generate a Makefile for the selected host,"
	error_msg "however the host-targeting compiler was found to be missing"
	error_msg "at least one of the required headers or features."
	exit 2
}


config_status()
{
	printf "\n\n"
	make .display
	printf "\nconfiguration completed successfully.\n\n"
}


config_failure()
{
	if [ -f Makefile ]; then
		mb_error='failed to use the generated Makefile.'
		printf '\n%s: error: %s\n' "${0}" "$mb_error" >&2
		mv Makefile Makefile.failed
	fi

	exit 2
}


config_success()
{
	trap '' EXIT
	exit 0
}


# one: init
init_vars
verify_build_directory


# two: args
for arg ; do
	case "$arg" in
		--help)	usage
			;;

		# dirs
		--prefix=*)
			mb_prefix_set=yes
			mb_prefix=${arg#*=}
			;;
		--exec-prefix=*)
			mb_exec_prefix_set=yes
			mb_exec_prefix=${arg#*=}
			;;
		--bindir=*)
			mb_bindir_set=yes
			mb_bindir=${arg#*=}
			;;
		--sbindir=*)
			mb_sbindir=${arg#*=}
			;;
		--libdir=*)
			mb_libdir=${arg#*=}
			;;
		--includedir=*)
			mb_includedir=${arg#*=}
			;;
		--oldincludedir=*)
			mb_oldincludedir=${arg#*=}
			;;
		--mandir=*)
			mb_mandir=${arg#*=}
			;;
		--libexecdir=*)
			mb_libexecdir=${arg#*=}
			;;


		--sysconfdir=*)
			mb_sysconfdir=${arg#*=}
			;;
		--sharedstatedir=*)
			mb_sharedstatedir=${arg#*=}
			;;
		--localstatedir=*)
			mb_localstatedir=${arg#*=}
			;;
		--runstatedir=*)
			mb_runstatedir=${arg#*=}
			;;
		--datarootdir=*)
			mb_datarootdir=${arg#*=}
			;;
		--datadir=*)
			mb_datadir=${arg#*=}
			;;
		--infodir=*)
			mb_infodir=${arg#*=}
			;;
		--localedir=*)
			mb_localedir=${arg#*=}
			;;
		--htmldir=*)
			mb_htmldir=${arg#*=}
			;;
		--dvidir=*)
			mb_dvidir=${arg#*=}
			;;
		--pdfdir=*)
			mb_pdfdir=${arg#*=}
			;;
		--psdir=*)
			mb_psdir=${arg#*=}
			;;


		# build
		--build=*)
			mb_build=${arg#*=}
			;;
		--host=*)
			mb_host=${arg#*=}
			;;
		--cchost=*)
			mb_cchost=${arg#*=}
			;;
		--cfghost=*)
			mb_cfghost=${arg#*=}
			;;
		--target=*)
			mb_target=${arg#*=}
			;;
		--arch=*)
			mb_arch=${arg#*=}
			;;
		--compiler=*)
			mb_compiler=${arg#*=}
			;;
		--toolchain=*)
			mb_toolchain=${arg#*=}
			;;
		--sysroot=*)
			mb_sysroot=${arg#*=}
			;;
		--cross-compile=*)
			mb_cross_compile=${arg#*=}
			;;
		--shell=*)
			mb_shell=${arg#*=}
			;;
		--debug)
			mb_debug=yes
			;;

		# config
		--all-static)
			mb_all_static=yes
			;;
		--all-shared)
			mb_all_shared=yes
			;;
		--disable-frontend)
			mb_disable_frontend=yes
			;;
		--disable-app)
			mb_disable_frontend=yes
			;;
		--enable-frontend)
			mb_disable_frontend='no'
			;;
		--enable-app)
			mb_disable_frontend='no'
			;;
		--disable-static)
			mb_disable_static=yes
			;;
		--disable-shared)
			mb_disable_shared=yes
			;;
		--enable-static)
			mb_disable_static='no'
			;;
		--enable-shared)
			mb_disable_shared='no'
			;;

		# convenience
		--strict)
			mb_ccstrict=yes
			mb_ldstrict=yes
			;;
		--ccstrict)
			mb_ccstrict=yes
			;;
		--ldstrict)
			mb_ldstrict=yes
			;;

		# project
		--nickname=*)
			mb_nickname=${arg#*=}
			;;
		--program-prefix=*)
			mb_program_prefix=${arg#*=}
			;;
		--avoid-version)
			mb_avoid_version=yes
			;;
		--source-dir=*)
			mb_source_dir=${arg#*=}
			;;

		# pkgconfig
		--pkgname=*)
			mb_pkgname=${arg#*=}
			;;

		--pkgdesc=*)
			mb_pkgdesc=${arg#*=}
			;;

		--pkgusrc=*)
			mb_pkgusrc=${arg#*=}
			;;

		--pkgrepo=*)
			mb_pkgrepo=${arg#*=}
			;;

		--pkgpsrc=*)
			mb_pkgpsrc=${arg#*=}
			;;

		--pkgdurl=*)
			mb_pkgdurl=${arg#*=}
			;;

		--pkgdefs=*)
			mb_pkgdefs=${arg#*=}
			;;

		--pkglibs=*)
			mb_pkglibs=${arg#*=}
			;;

		# compatibility
		--enable-dependency-tracking)
			;;
		--disable-dependency-tracking)
			;;

		*)
			if [ _$mb_use_custom_cfgdefs = _yes ]; then
				mb_escaped_arg=\'$(printf '%s\n' "$arg" | sed -e "s/'/'\\\\''/g")\'
				mb_escaped_arg="$mb_custom_cfgdefs_space$mb_escaped_arg"
				mb_custom_cfgdefs_args="$mb_custom_cfgdefs_args$mb_escaped_arg"
				mb_custom_cfgdefs_space=' '
			else
				error_msg ${arg#}: "unsupported config argument."
				exit 2
			fi
			;;
	esac
done



# three: validation
verify_source_directory

if ! [ -z "$mb_program_prefix" ]; then
	error_msg "--program-prefix is not yet fully support (must be null)."
fi



# four: defaults
common_defaults
native_defaults
cross_defaults



# five: config
config_flags
config_copy
config_custom
config_cfghost
config_support
config_host
config_status


# all done
config_success