mac 電腦上交叉編譯n2n,目標機arm linux
下載openssl-1.0.2p,並交叉編譯openssl，openssl的安裝目錄/opt/ssh/openssl-1.0.2p/_install
git clone https://github.com/meyerd/n2n.git
brew install cmake
~/n2n/n2n_v2$ mkdir build
~/n2n/n2n_v2$ cd build
編輯~/n2n/2n2_v2/CMakeLists.txt,找到set(CMAKE_C_FLAGS 和set(CMAKE_CXX_FLAGS 兩行
在這兩行的裏面括號裏面的部分, 加入編譯參數-I /opt/ssh/openssl-1.0.2p/_install/include -L /opt/ssh/openssl-1.0.2p/_install/lib
修改的內容如下:
# None
if(NOT WIN32)
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wshadow -Wpointer-arith -Wmissing-declarations -Wnested-externs -fPIC -I /opt/ssh/openssl-1.0.2p/_install/include -L /opt/ssh/openssl-1.0.2p/_install/lib")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wshadow -Wpointer-arith -Wmissing-declarations -Wnested-externs -I /opt/ssh/openssl-1.0.2p/_install/include -L /opt/ssh/openssl-1.0.2p/_install/lib")
# Debug
set(CMAKE_C_FLAGS_DEBUG "-g -fsanitize=address")
set(CMAKE_CXX_FLAGS_DEBUG "-g -fsanitize=address")
# Release
set(CMAKE_C_FLAGS_RELEASE "-O2 -DNDEBUG")
set(CMAKE_CXX_FLAGS_RELEASE "-O2 -DNDEBUG")
endif(NOT WIN32)
#for macOS, add openssl include dir
if(APPLE)
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -I /opt/ssh/openssl-1.0.2p/_install/include -L /opt/ssh/openssl-1.0.2p/_install/lib")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I /opt/ssh/openssl-1.0.2p/_install/include -L /opt/ssh/openssl-1.0.2p/_install/lib")
endif(APPLE)
~/n2n/n2n_v2/build$ cmake -DCMAKE_TOOLCHAIN_FILE=../cmake/am335x_armlinux_cmake.cmake --build ./ ../
~/n2n/n2n_v2/build$ make
沒有設置openssl的編譯路徑的話, 編譯到transform_aes.c.o會有提示錯誤openssl/aes.h: No such file or directory
~/n2n/n2n_v2/cmake/am335x_armlinux_cmake.cmake內容如下:
# the name of the target operating system
SET(CMAKE_SYSTEM_NAME Linux)
SET(OPENSSL_ROOT_DIR /opt/ssh/openssl-1.0.2p/_install)
# which compilers to use for C and C++
SET(CMAKE_C_COMPILER /Volumes/linux/gcc4.7.3-arm-linux-gnueabihf/install/bin/arm-cortex_a8-linux-gnueabihf-gcc)
SET(CMAKE_CXX_COMPILER /Volumes/linux/gcc4.7.3-arm-linux-gnueabihf/install/bin/arm-cortex_a8-linux-gnueabihf-g++)
# here is the target environment located
SET(CMAKE_FIND_ROOT_PATH /Volumes/linux/gcc4.7.3-arm-linux-gnueabihf/install /opt/ssh/openssl-1.0.2p/_install)
# adjust the default behaviour of the FIND_XXX() commands:
# search headers and libraries in the target environment, search
# programs in the host environment
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)