LIB_FILENAME ?= libvieter.a

BUILD_DIR ?= build
SRC_DIR ?= src
INC_DIRS ?= include

SRCS != find '$(SRC_DIR)' -iname '*.c'
OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
DEPS := $(SRCS:%=$(BUILD_DIR)/%.d)

INC_FLAGS := $(addprefix -I,$(INC_DIRS))

# -MMD: generate a .d file for every source file. This file can be imported by
#  make and makes make aware that a header file has been changed, ensuring an
#  object file is also recompiled if only a header is changed.
# -MP: generate a dummy target for every header file (according to the  docs it
#  prevents some errors when removing header files)
CFLAGS ?= $(INC_FLAGS) -O3 -MMD -MP -Wall -Werror -Wextra

.PHONY: all
all: vieter


# =====COMPILATION=====
.PHONY: vieter
vieter: $(BUILD_DIR)/$(LIB_FILENAME)
$(BUILD_DIR)/$(LIB_FILENAME): $(OBJS)
	ar -rcs $@ $(OBJS)

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


.PHONY: clean
clean:
	rm -rf $(BUILD_DIR)


# Make make aware of the .d files
-include $(DEPS)