CMake 笔记

说明

• 本页汇总 CMake 常用命令, 语法片段, 变量与属性排查方式.
• 适合作为写 CMakeLists.txt 或调试构建脚本时的速查页.

cmake 命令

cmake -B build 配置 编译目录 cmake –build build 运行 指定的编译路径 cmake –build build –target clean 清除编译目录 cmake -E remove_directory build

windows平台下指定架构: -A Win32 或 Win64 或 x64, 2019开始 无法使用 x86

cmake –trace-expand –loglevel=VERBOSE … –trace-expand 可以使变量值显示 –loglevel=VERBOSE 可以使message(VERBOSE …)有输出

cmake常用语法

set(ENV{WCHEVT_SDK_BASE} ${CMAKE_CURRENT_LIST_DIR})                     设置环境变量

include_directories(include)                                            设置头文件路径
link_directories(/usr/lib)                                              设置库路径

add_library(hello1 src/hello.cpp)                                       添加静态库
add_library(hello2 SHARED src/hello.cpp)                                添加动态库
add_executable(sayHello src/useHello.cpp)                               添加可执行程序
target_link_libraries(sayHello hello)                                   链接库

set(CMAKE_BUILD_TYPE Release)                                           设置编译类型, 默认就是Release

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")                    设置编译参数

set(CMAKE_CXX_STANDARD 11)

ADD_DEFINITIONS(-DmacroName -DmacroName=macroValue ......)              设置宏

file(GLOB SRC_FILES src/*.c src/*.h)                                    生成一个匹配条件的文件列表

set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR}/exec/)         设置可执行程序的生成目录

set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR}/lib/)          设置动态库的生成目录

set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR}/lib/static/)   设置静态库的生成目录

安装可执行程序或库:
install(
    TARGETS hello1 hello2
    RUNTIME DESTINATION bin
    ARCHIVE DESTINATION lib　#安装静态库到/usr/local/lib目录
    LIBRARY DESTINATION lib　#安装动态库到/usr/local/lib目录
)

install(
    #安装头文件到/usr/local/include目录
    FILES ${PROJECT_SOURCE_DIR}/include/hello.h DESTINATION include
)

install(
    DIRECTORIES ${PROJECT_SOURCE_DIR}/include/utils DESTINATION include
)

执行一个command,生成${TEST_FILE}文件
add_custom_command(OUTPUT  ${TEST_FILE}
    COMMAND echo "Generating log.txt file..."
    COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_LIST_FILE} ${TEST_FILE}
    COMMENT  "This is a test"
)
目标Test1,会等待${TEST_FILE}的生成,然后执行
add_custom_target(Test1 ALL DEPENDS ${TEST_FILE})

执行Test1 command
add_custom_command(TARGET Test1
    PRE_BUILD
    COMMAND echo "executing a fake command"
    COMMENT "This command will be executed before building target Test1"
)

搜集所有在指定路径下的源文件的文件名
aux_source_directory(< dir > < variable >)

CMAKE_C_FLAGS 设置C编译选项
CMAKE_CXX_FLAGS 设置C++编译选项


-DCMAKE_INSTALL_RPATH=/usr 编译期与运行期的rpath都会多一条
-DCMAKE_SKIP_RPATH=FALSE 编译期与运行期都不忽略RPATH


# cmake 获取所有的 include_directories
get_property(dirs DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY INCLUDE_DIRECTORIES)
foreach(dir ${dirs})
  message(STATUS "dir='${dir}'")
endforeach()


# cmake 获取target所有的属性
# Get all propreties that cmake supports
execute_process(COMMAND cmake --help-property-list OUTPUT_VARIABLE CMAKE_PROPERTY_LIST)

# Convert command output into a CMake list
STRING(REGEX REPLACE ";" "\\\\;" CMAKE_PROPERTY_LIST "${CMAKE_PROPERTY_LIST}")
STRING(REGEX REPLACE "\n" ";" CMAKE_PROPERTY_LIST "${CMAKE_PROPERTY_LIST}")

function(print_properties)
    message ("CMAKE_PROPERTY_LIST = ${CMAKE_PROPERTY_LIST}")
endfunction(print_properties)

function(print_target_properties tgt)

    if(NOT TARGET ${tgt})
      message("There is no target named '${tgt}'")
      return()
    endif()

    foreach (prop ${CMAKE_PROPERTY_LIST})
        string(REPLACE "<CONFIG>" "${CMAKE_BUILD_TYPE}" prop ${prop})
    # Fix https://stackoverflow.com/questions/32197663/how-can-i-remove-the-the-location-property-may-not-be-read-from-target-error-i
    if(prop STREQUAL "LOCATION" OR prop MATCHES "^LOCATION_" OR prop MATCHES "_LOCATION$")
        continue()
    endif()
        # message ("Checking ${prop}")
        get_property(propval TARGET ${tgt} PROPERTY ${prop} SET)
        if (propval)
            get_target_property(propval ${tgt} ${prop})
            message(STATUS "${tgt} ${prop} = ${propval}")
        endif()
    endforeach(prop)
endfunction(print_target_properties)

cmake常用的变量

PROJECT_NAME       项目名称
PROJECT_SOURCE_DIR 工程的根目录
PROJECT_BINARY_DIR 运行cmake命令的目录
CMAKE_INCLUDE_PATH 环境变量,非cmake变量
CMAKE_LIBRARY_PATH 环境变量
CMAKE_CURRENT_SOURCE_DIR 当前处理的CMakeLists.txt所在的路径
CMAKE_SOURCE_DIR cmake配置文件的顶层目录
CMAKE_BINARY_DIR
CMAKE_PREFIX_PATH
CMAKE_FILES_DIRECTORY
CMAKE_INSTALL_PREFIX

cmake_minimum_required(VERSION 2.8)

find_package(PkgConfig)
pkg_check_modules(audio_processing REQUIRED audio_processing)

# pkg-config --libs --cflags audio_processing
pkg_check_modules:
    <audio_processing>_FOUND          ... set to 1 if module(s) exist
    <audio_processing>_LIBRARIES      ... only the libraries (w/o the '-l')
    <audio_processing>_LIBRARY_DIRS   ... the paths of the libraries (w/o the '-L')
    <audio_processing>_LDFLAGS        ... all required linker flags
    <audio_processing>_LDFLAGS_OTHER  ... all other linker flags
    <audio_processing>_INCLUDE_DIRS   ... the '-I' preprocessor flags (w/o the '-I')
    <audio_processing>_CFLAGS         ... all required cflags
    <audio_processing>_CFLAGS_OTHER   ... the other compiler flags

    <audio_processing>_LIBDIR
    <audio_processing>_PREFIX

对于/usr/local/lib/pkgconfig下的pc文件

example: /usr/local/lib/pkgconfig/audio_process.pc:
    libdir=/usr/local/lib
    includedir=/usr/local/include

    Name: audio_processing
    Description: Webrtc audio process module
    Version: 0.1
    Libs: -L${libdir} -laudio_processing
    Cflags: -DWEBRTC_AUDIO_PROCESSING_ONLY_BUILD -I${includedir}/webrtc -DWEBRTC_POSIX

libdir:
    指定了库的路径

includedir:
    指定了库的头文件路径

Libs:
    -L: ${audio_process_LIBRARY_DIRS}
    -l: ${audio_process_LIBRARIES}

Cflags中的-I:
    指定了${audio_process_INCLUDE_DIRS}

-DWEBRTC_POSIX:
    表明需要一个WEBRTC_POSIX宏