# SPDX-License-Identifier: GPL-2.0+
.SUFFIXES:
MAKEFLAGS += -Rr
ifeq ("$(origin CC)", "default")
        CC := cc
endif
ifeq ("$(origin V)", "command line")
	SAY =
else
	SAY = @echo '$(strip $(1))'
endif

.ONESHELL:
.SHELLFLAGS := -ec
PREFIX ?= /usr/local
INSTALL ?= install
MKDIR_P := mkdir -p
RM := rm -f
CHMOD := chmod
GROFF := groff
B := build
all := misma misma.8
all: $(all)

PACKAGE := misma
SLOGAN := the minimal snapshot manager
AUTHOR := Andre Noll
EMAIL := maan@tuebingen.mpg.de
COPYRIGHT_YEAR := 2024
URL := http://people.tuebingen.mpg.de/maan/$(PACKAGE)/
CLONE_URL := git://git.tuebingen.mpg.de/$(PACKAGE)
GITWEB_URL := http://git.tuebingen.mpg.de/$(PACKAGE).git
HOME_URL := http://people.tuebingen.mpg.de/maan/
LICENSE := GPL-2.0+
LICENSE_URL := https://www.gnu.org/licenses/gpl-3.0-standalone.html
LOGLEVELS := LL_DEBUG,LL_INFO,LL_NOTICE,LL_WARNING,LL_ERROR,LL_CRIT,LL_EMERG

units := misma util version misma.lsg
deps := $(addprefix $(B)/, $(addsuffix .d, $(units)))
objs := $(addprefix $(B)/, $(addsuffix .o, $(units)))

ifeq ($(findstring clean, $(MAKECMDGOALS)),)
ifeq ($(findstring README, $(MAKECMDGOALS)),)
-include $(deps)
-include $(B)/config.mak
endif
endif

XCPPFLAGS :=
XCPPFLAGS += -I$(B)
XCPPFLAGS += -Wunused-macros
XCPPFLAGS += -DCOPYRIGHT_YEAR='"$(COPYRIGHT_YEAR)"'
XCPPFLAGS += -DPACKAGE='"$(PACKAGE)"'
XCPPFLAGS += -DAUTHOR='"$(AUTHOR)"'
XCPPFLAGS += -DEMAIL='"$(EMAIL)"'
XCPPFLAGS += -DURL='"$(URL)"'
XCPPFLAGS += -DCLONE_URL='"$(CLONE_URL)"'
XCPPFLAGS += -DGITWEB_URL='"$(GITWEB_URL)"'
XCPPFLAGS += -DHOME_URL='"$(HOME_URL)"'
XCPPFLAGS += -DGET_VERSION='$(PACKAGE)_version'
XCPPFLAGS += -DLOGLEVELS='$(LOGLEVELS)'
XCPPFLAGS += -DBUILD_DATE='"$(build_date)"'
XCPPFLAGS += -DCC_VERSION='"$(cc_version)"'
XCPPFLAGS += -DUNAME_RS='"$(uname_rs)"'
XCPPFLAGS += -DLICENSE='"$(LICENSE)"'
XCPPFLAGS += -DLICENSE_URL='"$(LICENSE_URL)"'

XCFLAGS :=
XCFLAGS += -fno-strict-aliasing
XCFLAGS += -g
XCFLAGS += -Os
XCFLAGS += -Wundef -W -Wuninitialized
XCFLAGS += -Wchar-subscripts
XCFLAGS += -Werror-implicit-function-declaration
XCFLAGS += -Wmissing-noreturn
XCFLAGS += -Wbad-function-cast
XCFLAGS += -Wredundant-decls
XCFLAGS += -Wno-sign-compare -Wno-unknown-pragmas
XCFLAGS += -Wdeclaration-after-statement
XCFLAGS += -Wformat -Wformat-security -Wmissing-format-attribute
XCFLAGS += -fdata-sections -ffunction-sections
XCFLAGS += -Wstrict-prototypes
XCFLAGS += -Wshadow
XCFLAGS += -Wunused -Wall
XCFLAGS += -Wformat-signedness
XCFLAGS += -Wdiscarded-qualifiers

XLDFLAGS := -Wl,--gc-sections
version_file := $(B)/version.c
GIT_VERSION := $(shell $(MKDIR_P) $(B) && ./version-gen.sh $(PACKAGE) $(version_file))

CC_CMD = $(CC) -c -o $@ $(XCPPFLAGS) $(CPPFLAGS) \
	$(XCFLAGS) $(CFLAGS) -MMD -MF $(B)/$(*F).d -MT $@

$(objs): misma.h $(B)/misma.lsg.h Makefile

$(B):
	@$(MKDIR_P) $@

$(B)/config.h.in: configure.ac | $(B)
	$(call SAY, AH $<)
	cd $(B)
	autoheader -f ../configure.ac
$(B)/configure.sh: configure.ac | $(B)
	$(call SAY, AC $<)
	cd $(B)
	autoconf ../configure.ac > configure.sh
	$(CHMOD) 755 configure.sh
$(B)/config.status: $(B)/configure.sh | $(B)
	$(call SAY, SH $<)
	cd $(B)
	if test -x config.status; then \
		./config.status --quiet --recheck; \
	else \
		./configure.sh --no-create; \
	fi
$(B)/config.mak $(B)/config.h: $(B)/config.status config.mak.in $(B)/config.h.in
	$(call SAY, CS $@)
	cd $(B)
	ln -f ../config.mak.in
	./config.status -q
	test -f config.h && touch config.h

define DESCRIPTION1 :=
	PACKAGE() is an open source application which maintains snapshots of one
	or more thin provisioned logical volumes on Linux systems.
endef

define DESCRIPTION2 :=
	Snapshots are created and removed automatically according to the
	configured schedule. Old snapshots are replaced so that the time
	between two consecutive snapshots doubles at each step. To prevent data
	or metadata space exhaustion, the available space of the underlying
	thin pools is monitored periodically and snapshots are removed early
	when space gets tight.
endef

define DESCRIPTION3 :=
	Besides the run subcommand which implements snapshot scheduling and
	free space monitoring, PACKAGE() supports additional subcommands
	to list existing snapshots and the utilization of the thin pools,
	or to create/remove snapshots manually.
endef

define M4_CMD =
	$(call SAY, M4 $<)
	$(M4) -D "AUTHOR=$(AUTHOR)" -D "COPYRIGHT_YEAR=$(COPYRIGHT_YEAR)" \
		-D "PACKAGE=$(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 "LICENSE=$(LICENSE)" \
		-D "LICENSE_URL=$(LICENSE_URL)" \
		-D "DESCRIPTION1=$(DESCRIPTION1)" \
		-D "DESCRIPTION2=$(DESCRIPTION2)" \
		-D "DESCRIPTION3=$(DESCRIPTION3)"
endef

$(B)/logo.svg: index.html.m4 Makefile
	$(M4_CMD) -D MODE=svg $< > $@
$(B)/index.html: index.html.m4 Makefile
	$(M4_CMD) $< > $@
$(B)/misma.suite: misma.suite.m4 Makefile
	$(M4_CMD) $< > $@
$(B)/%.lsg.c: $(B)/%.suite
	$(call SAY, LSGC $<)
	$(LOPSUBGEN) --gen-c --output-dir $(B) < $<
$(B)/%.lsg.h: $(B)/%.suite
	$(call SAY, LSGH $<)
	$(LOPSUBGEN) --gen-header --output-dir $(B) < $<
%.8: $(B)/%.suite $(B)/version.c
	$(call SAY, LSGM $<)
	$(LOPSUBGEN) --gen-man=$(*F).8 --version-string $(GIT_VERSION) < $<
$(B)/%.8.html: %.8
	$(GROFF) -m man -Thtml -Wbreak < $< > $@

$(B)/%.o: %.c | $(B)
	$(call SAY, CC $<)
	$(CC_CMD) $<
$(B)/%.o: $(B)/%.c
	$(call SAY, CC $<)
	$(CC_CMD) $<
$(PACKAGE): $(objs)
	$(call SAY, LD $@)
	$(CC) -o $@ $^ $(XLDFLAGS) $(LDFLAGS) -llopsub -lm
$(B)/$(PACKAGE): $(objs)
	$(call SAY, LD-STATIC $@)
	$(CC) -static -o $@ $^ $(XLDFLAGS) $(LDFLAGS) -llopsub -lm

mandir := $(datarootdir)/man/man8
INSTALL ?= install
INSTALL_PROGRAM ?= $(INSTALL) -m 755
INSTALL_DATA ?= $(INSTALL) -m 644
ifneq ($(findstring strip, $(MAKECMDGOALS)),)
	strip_option := -s
endif
install install-strip: all
	$(MKDIR_P) $(DESTDIR)$(sbindir) $(DESTDIR)$(mandir)
	$(INSTALL_PROGRAM) $(strip_option) misma $(DESTDIR)$(sbindir)
	$(INSTALL_DATA) misma.8 $(DESTDIR)$(mandir)

clean:
	$(RM) $(B)/*.o $(all)
distclean: clean
	$(RM) -r $(B)
maintainer-clean:
	git clean -dfqx > /dev/null 2>&1

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

$(DESCRIPTION1)

$(DESCRIPTION2)

$(DESCRIPTION3)

Resources
~~~~~~~~~
|	web page: $(URL)
|	git clone URL: $(CLONE_URL)
|	gitweb: $(GITWEB_URL)
|	author's home page: $(HOME_URL)
|	Send feedback to: $(AUTHOR) <$(EMAIL)>

License
~~~~~~~
Open source, licensed under the $(LICENSE) license.

Documentation
~~~~~~~~~~~~~
See misma.suite.m4. Or build the man page with \"make\" and run
\"man -l misma.8\".

Dependencies
~~~~~~~~~~~~
This package requires m4, autoconf, gnu make, gcc or clang, and
lopsub. The configure script checks if all dependencies are installed
and prints a meaningful error message if one of them is missing.

Building
~~~~~~~~
Run \"make\" to build the package with the default settings. Run
\"./configure -h\" to list configuration options.

Installation
~~~~~~~~~~~~
Run \"sudo make install\" to install to /usr/local. To install to
/somewhere/else, run \"./configure --prefix /somewhere/else && make\"
first.
endef

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

.PRECIOUS: $(B)/%.lsg.c $(B)/%.lsg.h $(B)/%.8
.PHONY: all clean install distclean maintainer-clean README
-include Makefile.local