如何从Makefile中的其他目录导入所有源代码和头文件

Question

I am very unfamiliar with makefiles and am trying to figure out how to setup googletest and the makefile in a project. How would one import all source and header files from the project which can be found in other directories, into the makefile build so that I could access the header files within the test files?

The structure looks like this

project_root/
            commons/core/{lots of files}
            commons/backends/{lots of files}
            os/core/{lots of files}
            public/os/{lots of files}
            wsi/comp/{lots of files}
            tests/googletests/[Makefile tests/ include/ src/] # where I am testing from.

I would like to have all the .h and .cpp files accessible to files in tests/googletests/tests/ but I am unsure how to do that with the Makefile.

Inside the tests folder I am using the sample1.h, sample1.cc, and sample1_unnitetest.cc to play around with trying to load header files from other places found here: https://github.com/google/googletest/tree/master/googletest/samples

The makefile i am using is:

# A sample Makefile for building Google Test and using it in user
# tests.  Please tweak it to suit your environment and project.  You
# may want to move it to your project's root directory.
#
# SYNOPSIS:
#
#   make [all]  - makes everything.
#   make TARGET - makes the given target.
#   make clean  - removes all files generated by make.

# Please tweak the following variable definitions as needed by your
# project, except GTEST_HEADERS, which you can use in your own targets
# but shouldn't modify.

# Points to the root of Google Test, relative to where this file is.
# Remember to tweak this if you move this file.
GTEST_DIR = .

# Where to find user code.
USER_DIR = ./tests

# Flags passed to the preprocessor.
# Set Google Test's header directory as a system directory, such that
# the compiler doesn't generate warnings in Google Test headers.
CPPFLAGS += -isystem $(GTEST_DIR)/include

# Flags passed to the C++ compiler.
CXXFLAGS += -g -Wall -Wextra -pthread

# All tests produced by this Makefile.  Remember to add new tests you
# created to the list.
TESTS = sample1_unittest

# All Google Test headers.  Usually you shouldn't change this
# definition.
GTEST_HEADERS = $(GTEST_DIR)/include/gtest/*.h \
                $(GTEST_DIR)/include/gtest/internal/*.h

# House-keeping build targets.

all : $(TESTS)

clean :
    rm -f $(TESTS) gtest.a gtest_main.a *.o

# Builds gtest.a and gtest_main.a.

# Usually you shouldn't tweak such internal variables, indicated by a
# trailing _.
GTEST_SRCS_ = $(GTEST_DIR)/src/*.cc $(GTEST_DIR)/src/*.h $(GTEST_HEADERS)

# For simplicity and to avoid depending on Google Test's
# implementation details, the dependencies specified below are
# conservative and not optimized.  This is fine as Google Test
# compiles fast and for ordinary users its source rarely changes.
gtest-all.o : $(GTEST_SRCS_)
    $(CXX) $(CPPFLAGS) -I$(GTEST_DIR) $(CXXFLAGS) -c \
            $(GTEST_DIR)/src/gtest-all.cc

gtest_main.o : $(GTEST_SRCS_)
    $(CXX) $(CPPFLAGS) -I$(GTEST_DIR) $(CXXFLAGS) -c \
            $(GTEST_DIR)/src/gtest_main.cc

gtest.a : gtest-all.o
    $(AR) $(ARFLAGS) $@ $^

gtest_main.a : gtest-all.o gtest_main.o
    $(AR) $(ARFLAGS) $@ $^

# Builds a sample test.  A test should link with either gtest.a or
# gtest_main.a, depending on whether it defines its own main()
# function.

sample1.o : $(USER_DIR)/sample1.cc $(USER_DIR)/sample1.h $(GTEST_HEADERS)
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $(USER_DIR)/sample1.cc

sample1_unittest.o : $(USER_DIR)/sample1_unittest.cc \
                     $(USER_DIR)/sample1.h $(GTEST_HEADERS)
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $(USER_DIR)/sample1_unittest.cc

sample1_unittest : sample1.o sample1_unittest.o gtest_main.a
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -lpthread $^ -o $@

Answer 1

You haven't given us enough information to reproduce your problem , but this may be enough:

PROJECT_ROOT := ../../..
# or you can use an absolute path

OTHER_DIRS := $(addprefix $(PROJECT_ROOT)/, commons/core commons/backends os/core public/os wsi/comp)

VPATH = $(OTHER_DIRS)
CPPFLAGS += $(addprefix -I, $(OTHER_DIRS))

Now you can construct a new test:

something.o : something.cc whatever.h $(GTEST_HEADERS)
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $<

something_unittest.o : $(USER_DIR)/something_unittest.cc whatever.h $(GTEST_HEADERS)
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $<

something_unittest : something.o something_unittest.o gtest_main.a
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -lpthread $^ -o $@

If this doesn't work, we can investigate and adjust. Further refinements are possible, once this much is working.