CMakeLists.txt for lazybones like me

CMakeLists.txt

cmake_minimum_required(VERSION 3.3.0)
project(blablabla VERSION 0.1.0)

set(CMAKE_CXX_STANDARD 20)

#include(${CMAKE_BINARY_DIR}/conanbuildinfo.cmake)
#conan_basic_setup()

#include_directories(${CONAN_INCLUDE_DIRS})
#link_directories(${CONAN_LIB_DIRS})
#link_libraries(${CONAN_LIBS} ${CONAN_SYSTEM_LIBS})

message("-- Search files in ${CMAKE_CURRENT_SOURCE_DIR}")

set(accepted_extension .cc .cpp .cxx)

file(GLOB entries RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} "*")
foreach(filepath IN LISTS entries)
    set(filepath "${CMAKE_CURRENT_SOURCE_DIR}/${filepath}")
    if(IS_DIRECTORY "${filepath}" AND EXISTS "${filepath}/CMakeLists.txt" AND NOT IS_DIRECTORY "${filepath}/CMakeLists.txt")
        message("-- including subdir ${filepath}")
        add_subdirectory(${filepath})
    else()
        get_filename_component(extension ${filepath} LAST_EXT)
        if(extension IN_LIST accepted_extension)
            get_filename_component(target ${filepath} NAME_WE)
            message(" -- build ${filepath} -> ${target}")
            add_executable(${target} ${filepath})
        endif()
    endif()
endforeach()

CMakeListsInSubdir.cmake

message("-- Search files in ${CMAKE_CURRENT_SOURCE_DIR}")

set(accepted_extension .cc .cpp .cxx)

file(GLOB entries RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} "*")
foreach(filepath IN LISTS entries)
    set(filepath "${CMAKE_CURRENT_SOURCE_DIR}/${filepath}")
    if(IS_DIRECTORY "${filepath}" AND EXISTS "${filepath}/CMakeLists.txt" AND NOT IS_DIRECTORY "${filepath}/CMakeLists.txt")
        message("-- including subdir ${filepath}")
        add_subdirectory(${filepath})
    else()
        get_filename_component(extension ${filepath} LAST_EXT)
        if(extension IN_LIST accepted_extension)
            get_filename_component(target ${filepath} NAME_WE)
            message(" -- build ${filepath} -> ${target}")
            add_executable(${target} ${filepath})
        endif()
    endif()
endforeach()

最近重新学C++，重新写C++，一个个文件创建也没有多麻烦……但是就是懒……就写了简单的一个个目录自己找源文件的逻辑。不需要自己一个个写add_executable，只要复制CMakeLists就够了。万一要改个配置啊什么的，也可以在目录里面的CMakeLists直接改就行。

还有一种写法是直接用file(GLOB_RECURSE ...)获取所有文件，然后每个文件根据路径生成一个target，一个CMakeLists搞定。如果只是打打oj，那这样做完全ok。但是这样有个问题是如果要对单个target做一些修改，比如说想要几个文件生成一个target或者生成lib或者什么的，就会非常麻烦。所以自己决定啦。要用这种更无脑但是比较难改的也很简单，只要把GLOB改成GLOB_RECURSE在CMAKE_SOURCE_DIR中搜索就可以了。

message("-- Search files in ${CMAKE_SOURCE_DIR}")

set(accepted_extension .cc .cpp .cxx)

file(GLOB entries RELATIVE ${CMAKE_SOURCE_DIR} "*")
foreach(filepath IN LISTS entries)
    set(filepath "${CMAKE_SOURCE_DIR}/${filepath}")
    get_filename_component(extension ${filepath} LAST_EXT)
    if(extension IN_LIST accepted_extension)
        get_filename_component(target ${filepath} NAME_WE)
        message(" -- build ${filepath} -> ${target}")
        add_executable(${target} ${filepath})
    endif()
endforeach()