NAME := kernel
SPECFILE := kernel.spec


WORKDIR := $(shell pwd)
SPECDIR ?= $(WORKDIR)
SRCRPMDIR ?= $(WORKDIR)/srpm
BUILDDIR ?= $(WORKDIR)
RPMDIR ?= $(WORKDIR)/rpm
SOURCEDIR := $(WORKDIR)

NO_OF_CPUS := $(shell grep -c ^processor /proc/cpuinfo)

RPM_DEFINES := --define "_sourcedir $(SOURCEDIR)" \
		--define "_specdir $(SPECDIR)" \
		--define "_builddir $(BUILDDIR)" \
		--define "_srcrpmdir $(SRCRPMDIR)" \
		--define "_rpmdir $(RPMDIR)"

ifndef NAME
$(error "You can not run this Makefile without having NAME defined")
endif
ifndef VERSION
VERSION := $(shell cat version)
endif
ifndef RELEASE
RELEASE := $(shell cat rel)
endif

ifneq ($(VERSION),$(subst -rc,,$(VERSION)))
DOWNLOAD_FROM_GIT=1
VERIFICATION := hash
else
VERIFICATION := signature
endif

all: help

MIRROR := cdn.kernel.org
ifeq (,$(DISTFILES_MIRROR))
SRC_BASEURL := https://${MIRROR}/pub/linux/kernel/v$(shell echo $(VERSION) | sed 's/^\(2\.[0-9]*\).*/\1/;s/^3\..*/3.x/;s/^4\..*/4.x/;s/^5\..*/5.x/')
else
SRC_BASEURL := $(DISTFILES_MIRROR)
endif

ifeq ($(VERIFICATION),signature)
SRC_FILE := linux-${VERSION}.tar.xz
SIGN_FILE := linux-${VERSION}.tar.sign
else
SRC_FILE := linux-${VERSION}.tar.gz
HASH_FILE := $(SRC_FILE).sha512
endif

WG_BASE_URL := https://git.zx2c4.com/wireguard-linux-compat/snapshot
WG_SRC_FILE := wireguard-linux-compat-0.0.20200105.tar.xz

WG_SRC_URL := $(WG_BASE_URL)/$(WG_SRC_FILE)
WG_SIG_FILE := $(WG_SRC_FILE:%.xz=%.asc)
WG_SIG_URL := $(WG_BASE_URL)/$(WG_SIG_FILE)

URL := $(SRC_BASEURL)/$(SRC_FILE)
URL_SIGN := $(SRC_BASEURL)/$(SIGN_FILE)

ifeq ($(DOWNLOAD_FROM_GIT),1)
URL := https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/snapshot/linux-$(VERSION).tar.gz
endif

get-sources: $(SRC_FILE) $(SIGN_FILE) $(WG_SRC_FILE) $(WG_SIG_FILE)

$(SRC_FILE):
	@wget -q -N $(URL)

$(SIGN_FILE):
	@wget -q -N $(URL_SIGN)

$(WG_SRC_FILE):
	@wget -q -N $(WG_SRC_URL)

$(WG_SIG_FILE):
	@wget -q -N $(WG_SIG_URL)

import-keys:
	@if [ -n "$$GNUPGHOME" ]; then rm -f "$$GNUPGHOME/linux-kernel-trustedkeys.gpg"; fi
	@gpg --no-auto-check-trustdb --no-default-keyring --keyring linux-kernel-trustedkeys.gpg -q --import kernel*-key.asc
	@if [ -n "$$GNUPGHOME" ]; then rm -f "$$GNUPGHOME/wireguard-trustedkeys.gpg"; fi
	@gpg --no-auto-check-trustdb --no-default-keyring --keyring wireguard-trustedkeys.gpg -q --import wireguard*-key.asc

verify-sources: import-keys
	@xzcat $(WG_SRC_FILE) | gpgv --keyring wireguard-trustedkeys.gpg $(WG_SIG_FILE) - 2>/dev/null
ifeq ($(VERIFICATION),signature)
	@xzcat $(SRC_FILE) | gpgv --keyring linux-kernel-trustedkeys.gpg $(SIGN_FILE) - 2>/dev/null
else
	# there are no signatures for rc tarballs
	# verify locally based on a signed git tag and commit hash file
	sha512sum --quiet -c $(HASH_FILE)
endif

.PHONY: clean-sources
clean-sources:
ifneq ($(SRC_FILE), None)
	-rm $(SRC_FILE) $(SIGN_FILE)
endif
ifneq ($(WG_SRC_FILE), None)
	-rm $(WG_SRC_FILE) $(WG_SIG_FILE)
endif


#RPM := rpmbuild --buildroot=/dev/shm/buildroot/
RPM := rpmbuild 

RPM_WITH_DIRS = $(RPM) $(RPM_DEFINES)

rpms: rpms-dom0

rpms-vm:

rpms-dom0: get-sources $(SPECFILE)
	$(RPM_WITH_DIRS) -bb $(SPECFILE)
	rpm --addsign $(RPMDIR)/x86_64/*$(VERSION)-$(RELEASE)*.rpm

rpms-nobuild:
	$(RPM_WITH_DIRS) --nobuild -bb $(SPECFILE)

rpms-just-build: 
	$(RPM_WITH_DIRS) --short-circuit -bc $(SPECFILE)

rpms-install: 
	$(RPM_WITH_DIRS) -bi $(SPECFILE)

prep: get-sources $(SPECFILE)
	$(RPM_WITH_DIRS) -bp $(SPECFILE)

srpm: get-sources $(SPECFILE)
	$(RPM_WITH_DIRS) -bs $(SPECFILE)

verrel:
	@echo $(NAME)-$(VERSION)-$(RELEASE)

# mop up, printing out exactly what was mopped.

.PHONY : clean
clean ::
	@echo "Running the %clean script of the rpmbuild..."
	$(RPM_WITH_DIRS) --clean --nodeps $(SPECFILE)

help:
	@echo "Usage: make <target>"
	@echo
	@echo "get-sources      Download kernel sources from kernel.org"
	@echo "verify-sources"
	@echo
	@echo "prep             Just do the prep"	
	@echo "rpms             Build rpms"
	@echo "rpms-nobuild     Skip the build stage (for testing)"
	@echo "rpms-just-build  Skip packaging (just test compilation)"
	@echo "srpm             Create an srpm"
	@echo
	@echo "make update-repo-current  -- copy newly generated rpms to qubes yum repo"
	@echo "make update-repo-current-testing  -- same, but to -current-testing"
	@echo "make update-repo-unstable -- same, but to -unstable repo"