我目前正在制作一个将使用OpenSSL的静态库。当CMake生成MakeFiles时，OpenSSL库没有链接在其中，因此编译失败并出现错误：
iot.c:(.text+0x3f5): undefined reference to `EVP_sha256'
iot.c:(.text+0x41c): undefined reference to `HMAC'
我首先想到的可能是CMake指令应该放在应该放在iotlib / CMakeLists.txt中的CMakeLists.txt中，但是在生成MakeFiles时我会遇到错误。
主文件只是使用iotlib和测试，而库的所有代码都在iotlib文件中。
我的CMakeLists.txt的代码
cmake_minimum_required(VERSION 3.5)
project(iotcloud_lib)
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/CMakeModules/")
enable_testing()
# Includes for checkers
include(cppcheck.cmake) # TODO: Move to a module
set(CMAKE_BINARY_DIR ${CMAKE_SOURCE_DIR}/bin)
set(EXECUTABLE_OUTPUT_PATH ${CMAKE_BINARY_DIR})
set(LIBRARY_OUTPUT_PATH ${CMAKE_BINARY_DIR})
# Set compiler flags
set (warnings "-Wall -Wextra -Werror")
include_directories("${PROJECT_SOURCE_DIR}")
add_subdirectory(iotlib)
add_subdirectory(tests)
add_executable(iotcloud ${PROJECT_SOURCE_DIR}/main.c)
find_package(OpenSSL REQUIRED)
include_directories(${OPENSSL_INCLUDE_DIR})
target_link_libraries(iotcloud ${OPENSSL_LIBRARIES})
target_link_libraries(iotcloud iotlib)
我的iotlib / CMakeLists.txt中的行
add_library (iotlib STATIC iot.c)
这就是我决定使用我的文件夹结构的方式。
+-- bin
+-- build
| +-- MakeFile
| +-- iotlib
| +-- MakeFile
+-- CMakeLists.txt
+-- CMakeModules
| +-- FindCheck.cmake
| +-- FindOpenSSL.cmake
| +-- FindPackageHandleStandardArgs.cmake
| +-- FindPackageMessage.cmake
+-- cppcheck.cmake
+-- iotlib
| +-- algo.h
| +-- CMakeLists.txt
| +-- iot.c
| +-- iot_error.h
| +-- iot.h
+-- main.c
+-- tests