# SPDX-License-Identifier: GPL-2.0

PACKAGE := dss
SLOGAN := the dyadic snapshot scheduler
define DESCRIPTION1 :=
	$(PACKAGE) maintains hardlink-based snapshots of a given directory on a
	remote or local host using rsync's link-dest feature. The snapshots
	are organized so that any snapshot can directly be deployed as an
	(emergency) replacement for the primary system.
endef
define DESCRIPTION2 :=
	$(PACKAGE) is admin friendly: It is easy to configure and needs little
	attention after the initial setup. In particular, no full, incremental
	or differential backups need to be configured, and there is no database
	to maintain. $(PACKAGE) is also user-friendly: Assuming the snapshot server
	allows read-only user access over the network, users can restore
	accidentically removed files without admin intervention, using their
	favorite file browser to copy files from the snapshot directory back
	to the primary system.
endef
define DESCRIPTION3 :=
	$(PACKAGE) keeps track of the age and the state of existing snapshots and
	triggers snapshot creation and removal according to the configuration
	settings. It tries to maintain a scheme where many recent snapshots
	and few old snapshots exist, for example 16 snapshots newer than a
	week, 8 snapshots between one and two weeks old, 4 snapshots between
	two and three weeks old, and so on.
endef
AUTHOR := Andre Noll
EMAIL := maan@tuebingen.mpg.de
URL := https://people.tuebingen.mpg.de/maan/$(PACKAGE)/
CLONE_URL := https://git.tuebingen.mpg.de/$(PACKAGE)
GITWEB_URL := https://git.tuebingen.mpg.de/$(PACKAGE).git
PACKAGE_HOMEPAGE := https://people.tuebingen.mpg.de/maan/$(PACKAGE)/
HOME_URL := https://people.tuebingen.mpg.de/maan/
LICENSE := GPL-2.0
LICENSE_URL := https://www.gnu.org/licenses/

PREFIX ?= /usr/local
INSTALL ?= install
INSTALL_PROGRAM ?= $(INSTALL)
INSTALL_DATA ?= $(INSTALL) -m 644
MKDIR_P := mkdir -p
VERSION := $(shell ./version-gen.sh $(PACKAGE) version.c)
RM := rm -f
LSG := lopsubgen
GROFF := groff -m man -Thtml -P -l -P -r
GZIP := gzip -cfn9
units := $(PACKAGE) $(PACKAGE).lsg str file exec sig daemon df tv snap ipc version
M4 := m4 \
	-D "AUTHOR=$(AUTHOR)" \
	-D "PACKAGE=$(PACKAGE)" \
	-D "SLOGAN=$(SLOGAN)" \
	-D "EMAIL=$(EMAIL)" \
	-D "URL=$(URL)" \
	-D "CLONE_URL=$(CLONE_URL)" \
	-D "GITWEB_URL=$(GITWEB_URL)" \
	-D "HOME_URL=$(HOME_URL)" \
	-D "PACKAGE_HOMEPAGE=$(PACKAGE_HOMEPAGE)" \
	-D "LICENSE=$(LICENSE)" \
	-D "LICENSE_URL=$(LICENSE_URL)" \
	-D "DESCRIPTION1=$(DESCRIPTION1)" \
	-D "DESCRIPTION2=$(DESCRIPTION2)" \
	-D "DESCRIPTION3=$(DESCRIPTION3)"
objs := $(addsuffix .o, $(units))
deps := $(addsuffix .d, $(units))
all := $(PACKAGE) $(PACKAGE).1.gz

all: $(all)
man: $(PACKAGE).1.gz
$(objs): $(PACKAGE).lsg.h Makefile
-include $(deps)

DSS_CPPFLAGS += -Wunused-macros

DSS_CFLAGS := -Wno-sign-compare -g -Wunused -Wundef
DSS_CFLAGS += -Wredundant-decls
DSS_CFLAGS += -Os
DSS_CFLAGS += -Wall
DSS_CFLAGS += -Wuninitialized
DSS_CFLAGS += -Wchar-subscripts
DSS_CFLAGS += -Wformat-security
DSS_CFLAGS += -Werror-implicit-function-declaration
DSS_CFLAGS += -Wmissing-format-attribute
DSS_CFLAGS += -Wunused-parameter
DSS_CFLAGS += -Wbad-function-cast
DSS_CFLAGS += -Wshadow

.ONESHELL:
.SHELLFLAGS := -ec
ifeq ("$(origin V)", "command line")
	SAY =
else
	SAY = @printf '%s\n' '$(strip $(1))'
endif
version.c:
	$(call SAY, VG $@)
	./version-gen.sh $(PACKAGE) version.c > /dev/null
$(PACKAGE): $(objs)
	$(call SAY, LD $@)
	$(CC) -o $@ $(objs) $(LDFLAGS) -llopsub
%.o: %.c
	$(call SAY, CC $<)
	$(CC) -c -o $@ $(DSS_CPPFLAGS) $(CPPFLAGS) $(DSS_CFLAGS) $(CFLAGS) \
		-MMD -MF $(*F).d -MT $@ $<
.PHONY: all clean install README
.PRECIOUS: %.lsg.c %.lsg.h %.suite %.1
$(PACKAGE).suite: $(PACKAGE).suite.m4 Makefile
	$(call SAY, M4 $<)
	$(M4) $< > $@
%.lsg.h: %.suite
	$(call SAY, LSGH $<)
	$(LSG) --gen-h=$@ < $<
%.lsg.c: %.suite
	$(call SAY, LSGC $<)
	$(LSG) --gen-c=$@ < $<
%.1: %.suite
	$(call SAY, LSGM $<)
	$(LSG) --gen-man=$@ --version-string=$(VERSION) < $<
%.1.gz: %.1
	$(call SAY, GZIP $<)
	$(GZIP) < $< > $@
%.1.html: %.1
	$(call SAY, GROFF $<)
	$(GROFF) $< > $@
clean:
	$(call SAY, CLEAN)
	$(RM) *.[od] $(all) *.html $(PACKAGE).1 $(PACKAGE).suite \
		$(PACKAGE).lsg.[ch] version.c

ifneq ($(findstring strip, $(MAKECMDGOALS)),)
       strip_option := -s
endif
bindir := $(DESTDIR)$(PREFIX)/bin
mandir := $(DESTDIR)$(PREFIX)/share/man/man1
install install-strip: all
	$(MKDIR_P) $(bindir) $(mandir)
	$(INSTALL_PROGRAM) $(strip_option) $(PACKAGE) $(bindir)
	$(INSTALL_DATA) $(PACKAGE).1.gz $(mandir)

define README :=
$(PACKAGE) - $(SLOGAN)

$(DESCRIPTION1)

$(DESCRIPTION2)

$(DESCRIPTION3)

Resources
~~~~~~~~~
web page: $(PACKAGE_HOMEPAGE)
git clone URL: $(CLONE_URL)
gitweb: $(GITWEB_URL)
author home page: $(HOME_URL)
report bugs to: $(AUTHOR) <$(EMAIL)>
endef

README:
	@printf '%s\n' "$(README)"

index.html.in: index.html.m4
	$(call SAY, M4 $<)
	$(M4) $< > $@
index.html: index.html.in INSTALL NEWS
	$(call SAY, MD $@)
	sed -e '/@README@/,$$d' index.html.in > $@
	printf '<p> %s </p>\n' "$(DESCRIPTION1)" >> $@
	printf '<p> %s </p>\n' "$(DESCRIPTION2)" >> $@
	printf '<p> %s </p>\n' "$(DESCRIPTION3)" >> $@
	sed -e '1,/@README@/d' -e '/@NEWS@/,$$d' index.html.in >> $@
	markdown NEWS >> $@
	sed -e '1,/@NEWS@/d' -e '/@INSTALL@/,$$d' index.html.in >> $@
	markdown INSTALL >> $@
	sed -e '1,/@INSTALL@/d' -e '/@MAN_PAGE@/,$$d' index.html.in >> $@

-include Makefile.local