MAKEFLAGS += --no-builtin-rules --no-builtin-variables --warn-undefined-variables
.ONESHELL:

# configurables

CC ?= cc
CC := $(CC)
CFLAGS ?=
LDFLAGS ?=

# end configurables

BASE_CFLAGS := \
	-std=c11 \
	-isystem/usr/local/lib/erlang/usr/include \
	-isystem/usr/lib/erlang/usr/include \
	-O2 \
	-fno-unwind-tables -fno-asynchronous-unwind-tables \
	-fno-plt \
	-fPIC \
	-flto

WARNING_CFLAGS := \
	-Wall -Wextra -Wvla -Wpedantic -Wconversion -Winline

BASE_LDFLAGS := -fPIC -flto -lzstd

DEPFLAGS = -MT $@ -MMD -MF c_out/$*.d

SOURCES := $(wildcard c_src/*.c)
HEADERS := $(wildcard c_src/*.h)
OBJECTS := $(SOURCES:%.c=c_out/%.o)
DEPFILES := $(SOURCES:%.c=c_out/%.d)

ALL_OBJECTS := $(OBJECTS)

all: c_out/ex_zstd_nif.so

c_out/ex_zstd_nif.so: $(ALL_OBJECTS)
	mkdir -p $(@D)
	$(CC) $(BASE_LDFLAGS) $(DEPFLAGS) $(LDFLAGS) \
	-fPIC -shared -o $@ $(ALL_OBJECTS)

c_out/c_src/%.o: c_src/%.c
	mkdir -p $(@D)
	$(CC) $(BASE_CFLAGS) $(WARNING_CFLAGS) $(DEPFLAGS) $(CFLAGS) -c -o $@ $<

-include $(DEPFILES)

.PHONY: install
install: c_out/ex_zstd_nif.so
	mkdir -p $(DESTDIR)
	cp c_out/ex_zstd_nif.so $(DESTDIR)

.PHONY: format
format:
	clang-format --style=file -i $(SOURCES) $(HEADERS)

.PHONY: lint
lint:
	clang-tidy --fix $(SOURCES)

.PHONY: clean
clean:
	rm -rf c_out

compile_commands.json:
	bear -- $(MAKE) \
		CC="$(CC)" \
		CFLAGS="$(BASE_CFLAGS) $(WARNING_CFLAGS) $(CFLAGS)" \
		LDFLAGS="$(BASE_LDFLAGS) $(LDFLAGS)" \
		$(OBJECTS)