VERSION    := 0.2.0
SOVERSION  := 1

CC         ?= cc
AR         ?= ar
CLANG_TIDY ?= clang-tidy
FORMAT     ?= clang-format
PREFIX     ?= /usr/local
LIBDIR     ?= $(PREFIX)/lib
INCLUDEDIR ?= $(PREFIX)/include
BINDIR     ?= $(PREFIX)/bin

FEATURES  := -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 -D_DEFAULT_SOURCE
WARNINGS  := -Wall -Wextra -Wpedantic -Wshadow -Wstrict-prototypes \
             -Wmissing-prototypes -Wold-style-definition -Wvla \
             -Wpointer-arith -Wcast-qual -Wredundant-decls

SAN       := -fsanitize=address,undefined -fno-omit-frame-pointer \
             -fno-sanitize-recover=all

CPPFLAGS  += -Iinclude -Isrc $(FEATURES)
CFLAGS    ?= -O2 -g
CFLAGS    += -std=c11 $(WARNINGS) $(EXTRA_CFLAGS)
LDFLAGS   += $(EXTRA_LDFLAGS)
LDLIBS    += -lcurl -lm

BUILD     := build
LIB_SRC   := src/client.c src/model.c src/util.c src/json.c src/csv.c
LIB_OBJ   := $(LIB_SRC:%.c=$(BUILD)/%.o)
PIC_OBJ   := $(LIB_SRC:%.c=$(BUILD)/%.pic.o)
TEST_SRC  := tests/test_cepis.c tests/test_server.c
TEST_OBJ  := $(TEST_SRC:%.c=$(BUILD)/%.o)
ALL_SRC   := $(LIB_SRC) src/cli.c $(TEST_SRC)
ALL_HDR   := include/cepis.h src/internal.h src/json.h src/csv.h \
             tests/test_server.h

STATIC    := $(BUILD)/libcepis.a
SHARED    := $(BUILD)/libcepis.so.$(VERSION)
CLI       := $(BUILD)/cepis
TESTS     := $(BUILD)/test_cepis

.DEFAULT_GOAL := help
.PHONY: help build test lint format check clean memcheck sanitize install \
	uninstall

help:
	@echo 'Targets:'
	@echo '  build      static and shared libraries, plus the cepis CLI'
	@echo '  test       build and run the suite against a local HTTP server'
	@echo '  lint       clang-format --dry-run + clang-tidy (read-only)'
	@echo '  format     apply clang-format (writes)'
	@echo '  check      lint, then test, then build'
	@echo '  memcheck   run the suite under valgrind'
	@echo '  sanitize   rebuild and run the suite under ASan + UBSan'
	@echo '  install    install headers, libraries and the CLI under PREFIX'
	@echo '  clean      remove $(BUILD)/'
	@echo
	@echo 'Override the compiler with e.g. make test CC=clang'

build: $(STATIC) $(SHARED) $(CLI)

$(BUILD)/%.o: %.c
	@mkdir -p $(dir $@)
	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@

$(BUILD)/%.pic.o: %.c
	@mkdir -p $(dir $@)
	$(CC) $(CPPFLAGS) $(CFLAGS) -fPIC -c $< -o $@

$(STATIC): $(LIB_OBJ)
	@mkdir -p $(dir $@)
	$(AR) rcs $@ $(LIB_OBJ)

$(SHARED): $(PIC_OBJ)
	@mkdir -p $(dir $@)
	$(CC) -shared -Wl,-soname,libcepis.so.$(SOVERSION) $(PIC_OBJ) \
		$(LDFLAGS) $(LDLIBS) -o $@
	ln -sf libcepis.so.$(VERSION) $(BUILD)/libcepis.so.$(SOVERSION)
	ln -sf libcepis.so.$(VERSION) $(BUILD)/libcepis.so

$(CLI): $(BUILD)/src/cli.o $(STATIC)
	$(CC) $(BUILD)/src/cli.o $(STATIC) $(LDFLAGS) $(LDLIBS) -o $@

$(TESTS): $(TEST_OBJ) $(STATIC)
	$(CC) $(TEST_OBJ) $(STATIC) $(LDFLAGS) $(LDLIBS) -lpthread -o $@

test: $(TESTS)
	$(TESTS)

# Read-only by design, so it is safe in CI and in a pre-commit hook: it reports
# what `make format` would change without changing anything.
lint:
	$(FORMAT) --dry-run --Werror $(ALL_SRC) $(ALL_HDR)
	$(CLANG_TIDY) --quiet $(ALL_SRC) -- $(CPPFLAGS) -std=c11

format:
	$(FORMAT) -i $(ALL_SRC) $(ALL_HDR)

# The order matters: lint is the fastest to fail, build the slowest, so a
# broken run reports the cheapest problem first.
check: lint test build

memcheck: $(TESTS)
	valgrind --error-exitcode=9 --leak-check=full --show-leak-kinds=definite,indirect \
		--errors-for-leak-kinds=definite,indirect --track-origins=yes $(TESTS)

# Rebuilt from scratch: the sanitizers change the ABI of the objects, so they
# must not be mixed with objects from an ordinary build.
sanitize:
	$(MAKE) clean
	$(MAKE) test EXTRA_CFLAGS='$(SAN)' EXTRA_LDFLAGS='$(SAN)'
	$(MAKE) clean

install: build
	install -d $(DESTDIR)$(INCLUDEDIR) $(DESTDIR)$(LIBDIR) $(DESTDIR)$(BINDIR)
	install -m 644 include/cepis.h $(DESTDIR)$(INCLUDEDIR)/
	install -m 644 $(STATIC) $(DESTDIR)$(LIBDIR)/
	install -m 755 $(SHARED) $(DESTDIR)$(LIBDIR)/
	ln -sf libcepis.so.$(VERSION) $(DESTDIR)$(LIBDIR)/libcepis.so.$(SOVERSION)
	ln -sf libcepis.so.$(VERSION) $(DESTDIR)$(LIBDIR)/libcepis.so
	install -m 755 $(CLI) $(DESTDIR)$(BINDIR)/

uninstall:
	rm -f $(DESTDIR)$(INCLUDEDIR)/cepis.h
	rm -f $(DESTDIR)$(LIBDIR)/libcepis.a
	rm -f $(DESTDIR)$(LIBDIR)/libcepis.so*
	rm -f $(DESTDIR)$(BINDIR)/cepis

clean:
	rm -rf $(BUILD)