#!/usr/bin/make -f
SHELL = /bin/sh -e

# in order to keep output non-intermixed together, disable parallel building
# of different targets in this d/rules but allow running parallel submakes
.NOTPARALLEL:
# DEB_BUILD_OPTIONS=parallel=N
MAKEFLAGS += $(subst parallel=,-j,$(filter parallel=%,${DEB_BUILD_OPTIONS}))

# Uncomment this to turn on verbose mode.
#export DH_VERBOSE=1
V = $(if $(filter terse, ${DEB_BUILD_OPTIONS}),,1)

# Activate full hardening build flags
export DEB_BUILD_MAINT_OPTIONS := hardening=+all
# Fast version of dpkg/architecture.mk defining all vars in one go
ifeq (${DEB_HOST_MULTIARCH},)
   $(foreach d, $(shell dpkg-architecture | sed 's/=/?=/'), $(eval export $d))
endif
include /usr/share/dpkg/default.mk

##############################################################################

TESTSUITE_ENV = SKIP_KNOWN_BUGS=y
#TESTSUITE_ENV = VERBOSE=y
# always run tests in UTF8 mode to verify unicode support
TESTSUITE_ENV += LANG=C.UTF-8 LC_ALL=C.UTF-8
TESTSUITE_ENV += SKIP_INTERNET_TESTS=y
# Required for testsuite/taskset.tests
TESTSUITE_ENV += SHELL='${SHELL}'
# dash echo does not understand -e, bb builds its own in this case
TESTSUITE_ENV += ECHO=/bin/echo

# build directory
b = b

# which flavours to build
flavours = deb static udeb

ifneq (${DEB_HOST_GNU_TYPE},${DEB_BUILD_GNU_TYPE})
export CROSS_COMPILE = ${DEB_HOST_GNU_TYPE}-
endif

# We filter the following from CFLAGS:
# -O2
#   to use the optimization setting from busybox's configuration and build
#   system, causing it to use -Os. This reduces built binaries' size
#   considerably, making it easier to fit on space constrained systems.
CFLAGS := $(filter-out -O2, ${CFLAGS})

# Avoid Kconfig outputting the timestamp into generated configuration files. We
# use this to compare against the configuration files in debian/config/pkg for
# builds on Linux so that we can detect upstream configuration changes (e.g.
# added applets).
export KCONFIG_NOTIMESTAMP=1

install-indep install-arch install \
binary-indep binary-arch binary \
: %:
	dh $@

##############################################################################

configure: $(patsubst %,$b/%/.stamp-setup, ${flavours})
$(addprefix configure-,${flavours}): configure-%: $b/%/.stamp-setup
.PHONY: configure $(addprefix configure-,${flavours})

$b/%/.stamp-setup: d = $b/$*
$b/%/.stamp-setup:
	rm -rf $d
	mkdir -p $d

# Generate the .config file. First variable assignment wins.
# Several steps..

# 1, put any arch-specific overrides so they will have higher precedence
# should be empty for linux
	cat debian/config/os/${DEB_HOST_ARCH_OS} > $d/.config

# 2, use the flavour-specific base config file.
	cat debian/config/pkg/$* >> $d/.config

# 3, sort out the result using oldconfig Kbuild machinery and generate Makefile
	yes "" | ${MAKE} -C $d -f "${CURDIR}/Makefile" KBUILD_SRC="${CURDIR}" silentoldconfig V=$V

# 4, on linux platform only, compare the re-generated config to the shipped
# config in the package in order to catch new/changed upstream options.
ifeq (linux,${DEB_HOST_ARCH_OS})
	diff -u debian/config/pkg/$* $d/.config
endif

	ln -s .config $@

##############################################################################

build-arch: $(patsubst %,$b/%/.stamp-build, ${flavours})
build: build-arch
$(addprefix build-,${flavours}): build-%: $b/%/.stamp-build
build-indep:
.PHONY: build build-arch build-indep $(addprefix build-,${flavours})

# busybox build procedure is very sensitive for (environment) variables, it will
# remake everything if CFLAGS or LD has changed between build and install phases
# (and install depends on build, so busybox will be rebuilt during install if
# any env var has changed).
# Another problem is that upstream build system (as of 1.35) can not take more
# than a single target to build when building in parallel, the build fails in
# this case.  So we can not ask it for `all install' for example.
# To work around this, we use the upstream makefile only at the build stage,
# providing all environment explicitly in a single place.
# And installing will be done without the help from upstream makefiles,
# based on the information in the generated busybox.links file.

$b/%/.stamp-build: d = $b/$*
$b/%/.stamp-build: $b/%/.stamp-setup
	${MAKE} -C $d all \
	 SKIP_STRIP=y \
	 BB_EXTRA_VERSION="${DEB_VENDOR} ${DEB_VERSION}" \
	 CONFIG_EXTRA_CFLAGS='${CFLAGS} ${CPPFLAGS}' \
	 CONFIG_EXTRA_LDFLAGS='${CFLAGS} ${LDFLAGS}' \
	 V=$V
	${MAKE} -C $d busybox.links
	ln -sf busybox $@

##############################################################################

build-arch: $(if $(filter nocheck,${DEB_BUILD_OPTIONS}),,test-deb)
$(addprefix test-,${flavours}): test-%: $b/%/.stamp-test
.PHONY: $(addprefix test-,${flavours})

$b/%/.stamp-test: d = $b/$*
$b/%/.stamp-test: $b/%/.stamp-build
	@echo ======== running testsuite in $d ========
	@if [ ! -f $d/testsuite/.setup ]; then \
	    rm  -rf $d/testsuite ; \
	    cp -al testsuite $d/ ; \
	    rm -f $d/testsuite/mdev.tests; \
	    [ ! -f debian/testsuite-${DEB_HOST_ARCH_OS}.diff ] || \
		patch -p1 -d $d/ \
		  < debian/testsuite-${DEB_HOST_ARCH_OS}.diff ; \
	    touch $d/testsuite/.setup ; \
	fi
	cd $d/testsuite && ${TESTSUITE_ENV} ./runtest
	touch $@

##############################################################################

clean:
	dh_clean $b/
	rm -f .kernelrelease # leftover from the build process
.PHONY: clean

##############################################################################

override_dh_auto_install:

override_dh_install: $(patsubst %,$b/%/.stamp-build, ${flavours})
	dh_install

	dh_install -pbusybox $b/deb/busybox bin/
	dh_install -pbusybox $b/deb/docs/busybox.1 usr/share/man/man1/

	dh_install -pbusybox-static $b/static/busybox bin/
	dh_install -pbusybox-static $b/static/docs/busybox.1 usr/share/man/man1/

	dh_install -pbusybox-udeb $b/udeb/busybox bin/
# for udeb we also need links. But we can not easily use `make install'
# (see comment above). So we run the install rules directly here:
	dh_link -pbusybox-udeb \
	  $$(grep -v sbin/init $b/udeb/busybox.links | sed 's|^|/bin/busybox |')

override_dh_installinit:
	dh_installinit -pbusybox-syslogd
	dh_installinit -pbusybox-syslogd --name=busybox-klogd

ifeq (linux,$(DEB_HOST_ARCH_OS))
# udhcpc
# udhcpd
	dh_installinit -pudhcpd --onlyscripts
endif

override_dh_gencontrol:
# after shlibdeps finished, grab ${shlibs:Depends} from busybox package
# and transform it into Built-Using field (also dpkg-query bug #588505)
	if [ -f debian/busybox.substvars ]; then \
	  pkgs=$$(sed -n -e's/([^)]*)//g' -e's/,//g' -e's/^shlibs:Depends=//p' debian/busybox.substvars); \
	  srcs=; for p in $$pkgs; do \
	    srcs="$$srcs $$(dpkg-query -f '$${source:Package} (= $${source:Version}),' -W $$p)"; \
	  done ; \
	  echo "built-using=$$srcs" >> debian/busybox-static.substvars ; \
	fi
	dh_gencontrol