# This Jamfile requires boost-build v2 to build.
# The version shipped with boost 1.34.0

import modules ;
import path ;
import os ;
import errors ;
import feature : feature ;
import package ;
import virtual-target ;
import cast ;

BOOST_ROOT = [ modules.peek : BOOST_ROOT ] ;
CXXFLAGS = [ modules.peek : CXXFLAGS ] ;
LDFLAGS = [ modules.peek : LDFLAGS ] ;

ECHO "CXXFLAGS =" $(CXXFLAGS) ;
ECHO "LDFLAGS =" $(LDFLAGS) ;
ECHO "OS =" [ os.name ] ;

if $(BOOST_ROOT)
{
	ECHO "building boost from source directory: " $(BOOST_ROOT) ;

	use-project /boost : $(BOOST_ROOT) ;
	alias boost_system : /boost/system//boost_system : : : <include>$(BOOST_ROOT) ;
}
else
{
	local boost-lib-search-path =
		<search>/usr/local/opt/boost/lib
		;

	local boost-include-path =
		<include>/usr/local/opt/boost/include
	;

	# the names are decorated in MacPorts.
	lib boost_system : : <target-os>darwin <name>boost_system-mt $(boost-lib-search-path)
		: : $(boost-include-path) ;

	# we can't add /usr/local/lib to the search path on mac, as that will
	# interfere with system libraries (specifically libjpeg)
	lib boost_system : : <name>boost_system $(boost-lib-search-path) <search>/usr/local/lib
		: : $(boost-include-path) <include>/usr/local/include ;
}

VERSION = 1.2.6 ;

rule linking ( properties * )
{
	local result ;
	if <simulator>on in $(properties)
	{
		result += <library>/libsimulator//simulator ;
	}

	if <target-os>windows in $(properties)
		&& ( <asserts>on in $(properties)
			|| <asserts>production in $(properties)
			|| <asio-debugging>on in $(properties) )
	{
		result += <library>dbghelp ;
	}

	# gcrypt libraries, if enabled
	if <crypto>gcrypt in $(properties)
	{
		result += <library>gcrypt ;
	}
	else if <crypto>openssl in $(properties)
	{
		result += <library>ssl ;
		result += <library>crypto ;
		if <target-os>linux in $(properties)
		{
			result += <library>dl ;
		}
	}
	else if <crypto>libcrypto in $(properties)
	{
		result += <library>crypto ;
		if <target-os>linux in $(properties)
		{
			result += <library>dl ;
		}
	}

	if <target-os>windows in $(properties)
		|| <target-os>cygwin in $(properties)
	{
		# socket functions on windows require winsock libraries
		result += <library>ws2_32
			<library>wsock32
			<library>iphlpapi
			<define>WIN32_LEAN_AND_MEAN
			<define>__USE_W32_SOCKETS
			<define>WIN32
			<define>_WIN32
		;

		# when DHT is enabled, we need ed25519 which in turn
		# needs entropy
		if ! <dht>off in $(properties)
		{
			result += <library>advapi32 ;
		}
	}

	if <target-os>android in $(properties)
	{
		result += <library>dl ;
	}

	if <target-os>beos in $(properties)
	{
		result += <library>netkit <library>gcc ;
	}

	if <target-os>haiku in $(properties)
	{
		result += <library>libnetwork <library>gcc ;
	}


	if <target-os>solaris in $(properties)
	{
		result += <library>libsocket <library>libnsl ;
	}

	if <target-os>darwin in $(properties)
		|| <target-os>iphone in $(properties)
	{
		# for ip_notifier
		result += <framework>CoreFoundation <framework>SystemConfiguration ;
	}

	if <iconv>on in $(properties)
	{
		result += <library>libiconv ;
	}

	if ( <toolset>gcc in $(properties)
			|| <toolset>clang in $(properties) )
		&& <target-os>linux in $(properties)
		&& ( <asserts>on in $(properties)
			|| <asserts>production in $(properties)
			|| <asio-debugging>on in $(properties) )
	{
		# for backtraces in assertion failures
		# which only works on ELF targets with gcc
		result += <linkflags>-export-dynamic <linkflags>-rdynamic ;
	}

	if <boost-link>static in $(properties)
	{
		if <link>shared in $(properties)
		{
			# if libtorrent is being built as a shared library
			# but we're linking against boost statically, we still
			# need to make boost think it's being built as a shared
			# library, so that it properly exports its symbols
			result += <define>BOOST_ALL_DYN_LINK ;
			result += <library>boost_system/<link>static/<define>BOOST_ALL_DYN_LINK ;
		}
		else
		{
			result += <library>boost_system/<link>static ;
		}

		if <toolset>gcc in $(properties)
			&& ! <target-os>windows in $(properties)
			&& <link>shared in $(properties)
		{
			result += <fpic>on ;
		}

	}
	else if <boost-link>shared in $(properties)
	{
		result += <library>boost_system/<link>shared ;
	}
	else
	{
		result += <library>boost_system ;
	}

	result += <define>BOOST_ALL_NO_LIB
		<define>BOOST_MULTI_INDEX_DISABLE_SERIALIZATION
		<define>BOOST_SYSTEM_NO_DEPRECATED
		;

	return $(result) ;
}

rule warnings ( properties * )
{
	local result ;

	if <warnings>off in $(properties)
	{
		return $(result) ;
	}

	if <toolset>clang in $(properties)
		|| <toolset>darwin in $(properties)
	{
		result += <cflags>-Weverything ;
		result += <cflags>-Wno-documentation ;
		result += <cxxflags>-Wno-c++98-compat-pedantic ;
		result += <cflags>-Wno-padded ;
		result += <cflags>-Wno-global-constructors ;
# this warns on any global static object, which are used for error_category
# objects
		result += <cflags>-Wno-exit-time-destructors ;

# enable these warnings again, once the other ones are dealt with
		result += <cflags>-Wno-weak-vtables ;

		result += <cflags>-Wno-return-std-move-in-c++11 ;
		result += <cflags>-Wno-unknown-warning-option ;

# libtorrent uses alloca() carefully
		result += <cflags>-Wno-alloca ;
	}

	if <toolset>gcc in $(properties)
	{
		result += <cflags>-Wall ;
		result += <cflags>-Wextra ;
		result += <cflags>-Wpedantic ;
#		result += <cflags>-Wmisleading-indentation ;
		result += <cflags>-Wparentheses ;
		result += <cflags>-Wvla ;
		result += <cxxflags>-Wc++11-compat ;
		result += <cflags>-Wno-format-zero-length ;
	}

	if <toolset>msvc in $(properties)
	{
		# on msvc this resolves to /W4
		result += <warnings>all ;

# enable these warnings again, once the other ones are dealt with

# disable warning C4251: 'identifier' : class 'type' needs to have dll-interface to be used by clients of class 'type2'
		result += <cflags>/wd4251 ;
# disable warning C4275: non DLL-interface classkey 'identifier' used as base for DLL-interface classkey 'identifier'
		result += <cflags>/wd4275 ;
# disable warning C4373: virtual function overrides, previous versions of the compiler did not override when parameters only differed by const/volatile qualifiers
		result += <cflags>/wd4373 ;
		# C4268: 'identifier' : 'const' static/global data initialized
		#        with compiler generated default constructor fills the object with zeros
		result += <cflags>/wd4268 ;
		# C4503: 'identifier': decorated name length exceeded, name was truncated
		result += <cflags>/wd4503 ;
	}

	return $(result) ;
}

# rule for adding the right source files
# depending on target-os and features
rule building ( properties * )
{
	local result ;

	if ( <asserts>off in $(properties) &&
		! <invariant-checks>off in $(properties) )
	{
		ECHO "'invariant-check' requires enabled 'asserts' mode. (e.g. specify build params: invariant-check=on asserts=on)" ;
		result += <build>no ;
	}

	if <toolset>msvc in $(properties)
	{
		# allow larger .obj files (with more sections)
		result += <cflags>/bigobj ;
	}

	if ( <asserts>production in $(properties)
		|| <asserts>on in $(properties) )
	{
		result += <source>src/assert.cpp ;
	}

	if <encryption>on in $(properties)
	{
		result += <source>src/pe_crypto.cpp ;
	}

	if ( <toolset>darwin in $(properties)
		|| <toolset>gcc in $(properties)
		|| <toolset>clang in $(properties)
		|| <toolset>clang-darwin in $(properties) )
		&& <link>shared in $(properties)
		# on GCC, enabling debugging in libstdc++
		# breaks the ABI and its ability to appear
		# in shared object interfaces, so when it's
		# enabled, just export everything (since we're)
		# probably not a production build anyway
		&& ! <debug-iterators>on in $(properties)
	{
		# hide non-external symbols
		result += <cflags>-fvisibility=hidden ;
		result += <cxxflags>-fvisibility-inlines-hidden ;

		if ( <toolset>gcc in $(properties) )
		{
			result += <linkflags>-Wl,-Bsymbolic ;
		}
	}

	return $(result) ;
}

rule tag ( name : type ? : property-set )
{
	name = [ virtual-target.add-prefix-and-suffix $(name) : $(type) : $(property-set) ] ;

	if $(type) = SHARED_LIB &&
		( ! ( [ $(property-set).get <target-os> ] in windows cygwin ) )
	{
		name = $(name).$(VERSION) ;
	}

	return $(name) ;
}

# the search path to pick up the openssl libraries from. This is the <search>
# property of those libraries
rule openssl-lib-path ( properties * )
{
	local OPENSSL_LIB = [ feature.get-values <openssl-lib> : $(properties) ] ;

	if <target-os>darwin in $(properties) && $(OPENSSL_LIB) = ""
	{
		# on macOS, default to pick up openssl from the homebrew installation
		# brew install openssl
		OPENSSL_LIB = /usr/local/opt/openssl/lib ;
	}
	else if <target-os>windows in $(properties) && $(OPENSSL_LIB) = ""
	{
		# on windows, assume openssl is installed to c:\OpenSSL-Win32
		if <address-model>64 in $(properties)
		{ OPENSSL_LIB = c:\\OpenSSL-Win64\\lib ; }
		else
		{ OPENSSL_LIB = c:\\OpenSSL-Win32\\lib ; }
	}

	local result ;
	result += <search>$(OPENSSL_LIB) ;
	return $(result) ;
}

# the include path to pick up openssl headers from. This is the
# usage-requirement for the openssl-related libraries
rule openssl-include-path ( properties * )
{
	local OPENSSL_INCLUDE = [ feature.get-values <openssl-include> : $(properties) ] ;

	if <target-os>darwin in $(properties) && $(OPENSSL_INCLUDE) = ""
	{
		# on macOS, default to pick up openssl from the homebrew installation
		# brew install openssl
		OPENSSL_INCLUDE = /usr/local/opt/openssl/include ;
	}
	else if <target-os>windows in $(properties) && $(OPENSSL_INCLUDE) = ""
	{
		# on windows, assume openssl is installed to c:\OpenSSL-Win32
		if <address-model>64 in $(properties)
		{ OPENSSL_INCLUDE = c:\\OpenSSL-Win64\\include ; }
		else
		{ OPENSSL_INCLUDE = c:\\OpenSSL-Win32\\include ; }
	}

	local result ;
	result += <include>$(OPENSSL_INCLUDE) ;
	return $(result) ;
}

feature openssl-lib : : free path ;
feature openssl-include : : free path ;

feature test-coverage : off on : composite propagated link-incompatible ;
feature.compose <test-coverage>on : <cflags>--coverage <linkflags>--coverage ;

feature predictive-pieces : on off : composite propagated ;
feature.compose <predictive-pieces>off : <define>TORRENT_DISABLE_PREDICTIVE_PIECES ;

feature share-mode : on off : composite propagated ;
feature.compose <share-mode>off : <define>TORRENT_DISABLE_SHARE_MODE ;

feature streaming : on off : composite propagated ;
feature.compose <streaming>off : <define>TORRENT_DISABLE_STREAMING ;

feature super-seeding : on off : composite propagated ;
feature.compose <super-seeding>off : <define>TORRENT_DISABLE_SUPERSEEDING ;

feature i2p : on off : composite propagated ;
feature.compose <i2p>on : <define>TORRENT_USE_I2P=1 ;
feature.compose <i2p>off : <define>TORRENT_USE_I2P=0 ;

feature iconv : auto on off : composite propagated ;
feature.compose <iconv>on : <define>TORRENT_USE_ICONV=1 ;
feature.compose <iconv>off : <define>TORRENT_USE_ICONV=0 ;

feature asserts : off on production system : composite propagated ;
feature.compose <asserts>on : <define>TORRENT_USE_ASSERTS=1 ;
feature.compose <asserts>production : <define>TORRENT_USE_ASSERTS=1 <define>TORRENT_PRODUCTION_ASSERTS=1 ;
feature.compose <asserts>system : <define>TORRENT_USE_ASSERTS=1 <define>TORRENT_USE_SYSTEM_ASSERTS=1 ;

feature windows-version : vista win7 xp : composite propagated ;
feature.compose <windows-version>vista : <define>_WIN32_WINNT=0x0600 ;
feature.compose <windows-version>win7 : <define>_WIN32_WINNT=0x0601 ;
feature.compose <windows-version>xp : <define>_WIN32_WINNT=0x0501 ;

feature extensions : on off : composite propagated link-incompatible ;
feature.compose <extensions>off : <define>TORRENT_DISABLE_EXTENSIONS ;

feature asio-debugging : off on : composite propagated link-incompatible ;
feature.compose <asio-debugging>on : <define>TORRENT_ASIO_DEBUGGING ;

feature picker-debugging : off on : composite propagated link-incompatible ;
feature.compose <picker-debugging>on : <define>TORRENT_DEBUG_REFCOUNTS ;

feature simulator : off on : composite propagated link-incompatible ;
feature.compose <simulator>on : <define>TORRENT_BUILD_SIMULATOR ;

feature invariant-checks : off on full : composite propagated link-incompatible ;
feature.compose <invariant-checks>on : <define>TORRENT_USE_INVARIANT_CHECKS=1 ;
feature.compose <invariant-checks>full : <define>TORRENT_USE_INVARIANT_CHECKS=1 <define>TORRENT_EXPENSIVE_INVARIANT_CHECKS ;

feature utp-log : off on : composite propagated link-incompatible ;
feature.compose <utp-log>on : <define>TORRENT_UTP_LOG_ENABLE ;

feature simulate-slow-read : off on : composite propagated ;
feature.compose <simulate-slow-read>on : <define>TORRENT_SIMULATE_SLOW_READ ;

feature logging : on off : composite propagated link-incompatible ;
feature.compose <logging>off : <define>TORRENT_DISABLE_LOGGING ;

feature dht : on off : composite propagated link-incompatible ;
feature.compose <dht>off : <define>TORRENT_DISABLE_DHT ;

feature encryption : on off : composite propagated link-incompatible ;
feature.compose <encryption>off : <define>TORRENT_DISABLE_ENCRYPTION ;

feature mutable-torrents : on off : composite propagated link-incompatible ;
feature.compose <mutable-torrents>off : <define>TORRENT_DISABLE_MUTABLE_TORRENTS ;

feature crypto : built-in openssl libcrypto gcrypt : composite propagated ;
feature.compose <crypto>openssl : <define>TORRENT_USE_LIBCRYPTO <define>TORRENT_USE_OPENSSL <define>OPENSSL_NO_SSL2 ;
feature.compose <crypto>libcrypto : <define>TORRENT_USE_LIBCRYPTO ;
feature.compose <crypto>gcrypt : <define>TORRENT_USE_LIBGCRYPT ;

feature openssl-version : 1.1 pre1.1 : composite propagated ;

feature deprecated-functions : on off : composite propagated link-incompatible ;
feature.compose <deprecated-functions>off : <define>TORRENT_NO_DEPRECATE ;

feature boost-link : default static shared : propagated composite ;

# msvc enables debug iterators by default in debug builds whereas GCC and
# clang do not, that's why "default" is there. msvc has incorrect noexcept
# constructors on some containers when enabling debug iterators, so it's
# possible to turn them off
feature debug-iterators : default off on : composite propagated link-incompatible ;
feature.compose <debug-iterators>on : <define>_GLIBCXX_DEBUG <define>_GLIBCXX_DEBUG_PEDANTIC ;
feature.compose <debug-iterators>off : <define>_ITERATOR_DEBUG_LEVEL=0 ;

feature fpic : off on : composite propagated link-incompatible ;
feature.compose <fpic>on : <cflags>-fPIC ;

feature profile-calls : off on : composite propagated link-incompatible ;
feature.compose <profile-calls>on : <define>TORRENT_PROFILE_CALLS=1 ;

# controls whether or not to export some internal
# libtorrent functions. Used for unit testing
feature export-extra : off on : composite propagated ;
# export some internal libtorrent functions
# in order to me able to unit test them.
# this is off by default to keep the export
# symbol table reasonably small
feature.compose <export-extra>on : <define>TORRENT_EXPORT_EXTRA ;


# this is a trick to get filename paths to targets to become shorter
# making it possible to build on windows, especially mingw seems particular
# for release builds, disable optimizations as they bump GCC over the edge of
# allowed memory usage on travis-ci
variant test_release : release
	: <asserts>production <debug-symbols>on
	<invariant-checks>full <boost-link>shared <optimization>off
	<export-extra>on <threading>multi
	<inlining>on <deprecated-functions>off
	;
variant test_debug : debug
	: <logging>on
	<invariant-checks>full <boost-link>shared
	<export-extra>on <threading>multi <asserts>on
	;
variant test_barebones : debug
	: <dht>off <extensions>off <logging>off <boost-link>shared
	<deprecated-functions>off <invariant-checks>off
	<export-extra>on <threading>multi <asserts>on
	;
variant test_arm : debug
	: <dht>off <extensions>off <logging>off
	<deprecated-functions>off <invariant-checks>off
	<export-extra>on <asserts>on
	;

lib advapi32 : : <name>advapi32 ;
lib user32 : : <name>user32 ;
lib shell32 : : <name>shell32 ;
lib gdi32 : : <name>gdi32 ;
lib z : : <link>shared <name>z ;

# openssl libraries on windows
alias ssl-deps : advapi32 user32 shell32 gdi32 ;

# pre OpenSSL 1.1 windows
lib crypto : ssl-deps : <target-os>windows <openssl-version>pre1.1 <name>libeay32
	<conditional>@openssl-lib-path : : <conditional>@openssl-include-path ;
lib ssl : ssl-deps : <target-os>windows <openssl-version>pre1.1 <name>ssleay32
	<use>crypto <conditional>@openssl-lib-path : : <conditional>@openssl-include-path ;

# OpenSSL 1.1+ windows
lib crypto : ssl-deps : <toolset>msvc <openssl-version>1.1 <name>libcrypto
	<conditional>@openssl-lib-path : : <conditional>@openssl-include-path ;
lib ssl : ssl-deps : <toolset>msvc <openssl-version>1.1 <name>libssl <use>crypto
	<conditional>@openssl-lib-path : : <conditional>@openssl-include-path ;

# generic OpenSSL
lib crypto : : <name>crypto <use>z <conditional>@openssl-lib-path : :
	<conditional>@openssl-include-path ;
lib ssl : : <name>ssl <use>crypto <conditional>@openssl-lib-path : :
	<conditional>@openssl-include-path ;

lib dbghelp : : <name>dbghelp ;

# required for networking on beos
lib netkit : : <name>net <search>/boot/system/lib <link>shared ;
lib gcc : : <name>gcc <link>static ;

# when using iconv
lib libiconv : : <name>iconv <link>shared <search>/usr/local/lib ;

# openssl on linux/bsd etc.
lib gcrypt : : <name>gcrypt <link>shared <search>/opt/local/lib ;
lib dl : : <link>shared <name>dl ;

lib libsocket : : <use>libnsl <name>socket <link>shared <search>/usr/sfw/lib <link>shared ;
lib libnsl : : <name>nsl <link>shared <search>/usr/sfw/lib <link>shared ;
lib libnetwork : : <name>network <link>shared ;

# socket libraries on windows
lib wsock32 : : <name>wsock32 <link>shared ;
lib ws2_32 : : <name>ws2_32 <link>shared ;
lib iphlpapi : : <name>iphlpapi <link>shared ;

SOURCES =
	alert
	alert_manager
	announce_entry
	assert
	bandwidth_limit
	bandwidth_manager
	bandwidth_queue_entry
	bdecode
	bitfield
	block_cache
	bloom_filter
	chained_buffer
	choker
	close_reason
	cpuid
	crc32c
	create_torrent
	disk_buffer_holder
	disk_buffer_pool
	disk_io_job
	disk_io_thread
	disk_io_thread_pool
	disk_job_fence
	disk_job_pool
	entry
	error_code
	file_storage
	escape_string
	string_util
	file
	path
	fingerprint
	gzip
	hasher
	hex
	http_connection
	http_stream
	http_parser
	identify_client
	ip_filter
	ip_notifier
	ip_voter
	listen_socket_handle
	merkle
	peer_connection
	platform_util
	bt_peer_connection
	web_connection_base
	web_peer_connection
	http_seed_connection
	peer_connection_handle
	i2p_stream
	instantiate_connection
	lazy_bdecode
	natpmp
	openssl
	packet_buffer
	piece_picker
	peer_list
	proxy_base
	puff
	random
	read_resume_data
	write_resume_data
	receive_buffer
	resolve_links
	session
	session_handle
	session_impl
	session_call
	settings_pack
	sha1
	sha1_hash
	socket_io
	socket_type
	socks5_stream
	stat
	storage
	storage_piece_set
	storage_utils
	torrent
	torrent_handle
	torrent_info
	torrent_peer
	torrent_peer_allocator
	torrent_status
	time
	tracker_manager
	http_tracker_connection
	udp_tracker_connection
	timestamp_history
	udp_socket
	upnp
	utf8
	utp_socket_manager
	utp_stream
	file_pool
	lsd
	enum_net
	broadcast_socket
	magnet_uri
	parse_url
	ConvertUTF
	xml_parse
	version
	peer_class
	peer_class_set
	part_file
	stat_cache
	request_blocks
	session_stats
	performance_counters
	resolver
	session_settings
	proxy_settings
	file_progress
	ffs
	add_torrent_params
	peer_info
	stack_allocator
	generate_peer_id

# -- extensions --
	ut_pex
	ut_metadata
	smart_ban
	;

KADEMLIA_SOURCES =
	dht_state
	dht_storage
	dht_tracker
	msg
	node
	node_entry
	refresh
	rpc_manager
	find_data
	node_id
	routing_table
	traversal_algorithm
	dos_blocker
	get_peers
	item
	get_item
	put_data
	ed25519
	sample_infohashes
	dht_settings
	;

ED25519_SOURCES =
	add_scalar
	fe
	ge
	key_exchange
	keypair
	sc
	sign
	verify
	;

local usage-requirements =
	<include>./include
	<include>./include/libtorrent
	<include>/usr/sfw/include
# freebsd doesn't seem to include this automatically
# and iconv.h is installed there
	<include>/usr/local/include
	<variant>release:<define>NDEBUG
	<define>_FILE_OFFSET_BITS=64
# enable cancel support in asio
	<define>BOOST_ASIO_ENABLE_CANCELIO
# make sure asio uses std::chrono
	<define>BOOST_ASIO_HAS_STD_CHRONO
	<conditional>@linking
# msvc optimizations
	<toolset>msvc,<variant>release:<linkflags>"/OPT:ICF=5"
	<toolset>msvc,<variant>release:<linkflags>"/OPT:REF"

	# disable bogus deprecation warnings on msvc8
	<toolset>msvc:<define>_SCL_SECURE_NO_DEPRECATE
	<toolset>msvc:<define>_CRT_SECURE_NO_DEPRECATE

	<cxxflags>$(CXXFLAGS)
	<linkflags>$(LDFLAGS)
	;

project torrent ;

lib torrent

	: # sources
	src/$(SOURCES).cpp

	: # requirements
	<threading>multi
	<define>TORRENT_BUILDING_LIBRARY
	<link>shared:<define>TORRENT_BUILDING_SHARED
	<define>BOOST_NO_DEPRECATED
	<link>shared:<define>BOOST_SYSTEM_SOURCE

	<dht>on:<source>src/kademlia/$(KADEMLIA_SOURCES).cpp
	<dht>on:<source>ed25519/src/$(ED25519_SOURCES).cpp
	<dht>on:<source>src/hasher512.cpp
	<dht>on:<source>src/sha512.cpp

	<conditional>@building
	<conditional>@warnings
	<cxxflags>$(CXXFLAGS)

	<tag>@tag

	$(usage-requirements)

	: # default build
	<threading>multi
	<c++-template-depth>512

	: # usage requirements
	$(usage-requirements)
	<link>shared:<define>TORRENT_LINKING_SHARED

	;

headers = [ path.glob-tree include/libtorrent : *.hpp ] ;

package.install install
	: <install-source-root>libtorrent
	:
	: torrent
	: $(headers)
	;

local header_targets ;
for local target in $(headers)
{
	if ! [ path.basename $(target) ] in windows.hpp win_util.hpp win_crypto_provider.hpp torrent_impl.hpp cppint_import_export.hpp
	{
		# this cast tells boost build that the header files really *are* cpp files
		# otherwise the object rule doesn't know which language to interpret them as
		obj header-build/$(target).o : [ cast.cast _ cpp : $(target) ]
			: <library>/torrent <cxxflags>-fsyntax-only ;
		explicit header-build/$(target).o ;
		header_targets += $(target) ;
	}
}

alias check-headers : header-build/$(header_targets).o ;
explicit check-headers ;