makefile

# Thanks to Job Vranish (https://spin.atomicobject.com/2016/08/26/makefile-c-projects/)
TARGET_EXEC := ca-1d

PACKAGE_DIR := ./package
PACKAGE_NAME := ca-1d.zip
BUILD_DIR := ./build/release
DBG_DIR := ./build/debug
SRC_DIRS := ./src

# Find all the C and C++ files we want to compile
# Note the single quotes around the * expressions. The shell will incorrectly expand these otherwise, but we want to send the * directly to the find command.
SRCS := $(shell find $(SRC_DIRS) -name '*.cpp' -or -name '*.c' -or -name '*.s')

# Prepends BUILD_DIR and appends .o to every src file
# As an example, ./your_dir/hello.cpp turns into ./build/./your_dir/hello.cpp.o
OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
DBG_OBJS := $(SRCS:%=$(DBG_DIR)/%.o)

# String substitution (suffix version without %).
# As an example, ./build/hello.cpp.o turns into ./build/hello.cpp.d
DEPS := $(OBJS:.o=.d)
DBG_DEPS := $(DBG_OBJS:.o=.d)

# Every folder in ./src will need to be passed to GCC so that it can find header files
INC_DIRS := $(shell find $(SRC_DIRS) -type d)
# Add a prefix to INC_DIRS. So moduleA would become -ImoduleA. GCC understands this -I flag
INC_FLAGS := $(addprefix -I,$(INC_DIRS))

# The -MMD and -MP flags together generate Makefiles for us!
# These files will have .d instead of .o as the output.
CPPFLAGS := $(INC_FLAGS) -MMD -MP

all: $(BUILD_DIR)/$(TARGET_EXEC)

debug: CXXFLAGS += -DDEBUG -g
debug: CFLAGS += -DDEBUG -g
debug: $(DBG_DIR)/$(TARGET_EXEC)

# The final build step.
$(DBG_DIR)/$(TARGET_EXEC): $(DBG_OBJS)
	$(CXX) $(DBG_OBJS) -o $@ $(LDFLAGS)

# Build step for C source
$(DBG_DIR)/%.c.o: %.c
	mkdir -p $(dir $@)
	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@

# Build step for C++ source
$(DBG_DIR)/%.cpp.o: %.cpp
	mkdir -p $(dir $@)
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $< -o $@

# The final build step.
$(BUILD_DIR)/$(TARGET_EXEC): $(OBJS)
	$(CXX) $(OBJS) -o $@ $(LDFLAGS)

# Build step for C source
$(BUILD_DIR)/%.c.o: %.c
	mkdir -p $(dir $@)
	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@

# Build step for C++ source
$(BUILD_DIR)/%.cpp.o: %.cpp
	mkdir -p $(dir $@)
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $< -o $@

format:
	find -iname "*.c" -o -iname "*.cc" -o -iname "*.cpp" -o -iname "*.cxx" -o -iname "*.h" -o -iname "*.hpp" | xargs clang-format -i --style=file

install: all
	@echo installing executable file to ${DESTDIR}${PREFIX}/bin
	@mkdir -p ${DESTDIR}${PREFIX}/bin
	@cp -f ${BUILD_DIR}/${TARGET_EXEC} ${DESTDIR}${PREFIX}/bin
	@chmod 755 ${DESTDIR}${PREFIX}/bin/${TARGET_EXEC}

package: all
	@echo packaging executable file to ${PACKAGE_DIR}/${PACKAGE_NAME}
	@mkdir -p ${PACKAGE_DIR}/${TARGET_EXEC}
	@cp -f ${BUILD_DIR}/${TARGET_EXEC} ${PACKAGE_DIR}/${TARGET_EXEC}/${TARGET_EXEC}
	@zip -r ${PACKAGE_DIR}/${PACKAGE_NAME} ${PACKAGE_DIR}/${TARGET_EXEC}

uninstall:
	@echo removing executable file from ${DESTDIR}${PREFIX}/bin
	$(RM) ${DESTDIR}${PREFIX}/bin/${TARGET_EXEC}

.PHONY: clean install uninstall format
clean:
	rm -rf $(BUILD_DIR)
	rm -rf $(DBG_DIR)

# Include the .d makefiles. The - at the front suppresses the errors of missing
# Makefiles. Initially, all the .d files will be missing, and we don't want those
# errors to show up.
-include $(DEPS)
-include $(DBG_DEPS)