简介

CMake是一个比make更高级的编译配置工具，它可以根据不同平台、不同的编译器，生成相应的Makefile或者vcproj项目。通过编写CMakeLists.txt，可以控制生成的Makefile，从而控制编译过程。CMake自动生成的Makefile不仅可以通过make命令构建项目生成目标文件，还支持安装（make install）、测试安装的程序是否能正确执行（make test，或者ctest）、生成当前平台的安装包（make package）、生成源码包（make package_source）、产生Dashboard显示数据并上传等高级功能，只要在CMakeLists.txt中简单配置，就可以完成很多复杂的功能，包括写测试用例。如果有嵌套目录，子目录下可以有自己的CMakeLists.txt。

步骤

编写CMakeLists.txt
执行命令cmake PATH 或 ccmake PATH 生成Makefile
使用make命令编译，make -j4 指定编译并行度
使用 make install 安装

编译

指定安装路径

参考这里

shell

# 3.15 +
$ cmake --install /path/to/build --prefix /path/to/install [--config <CONFIG>]

# < 3.15
$ cd build
$ cmake -DCMAKE_INSTALL_PREFIX=/path/to/install -P cmake_install.cmake

指定编译类型

shell

# 1
$ cmake -DCMAKE_INSTALL_PREFIX:PATH=/path/to/install -DCMAKE_BUILD_TYPE=Release /path/to/src

# 2
$ cmake --config Release --build . --target install

语法

CMakeLists.txt 的语法比较简单，由命令、注释和空格组成。# 后面的是注释。

commond (args ...)

commond为命令名，大小写不敏感
args为参数
- 如果包含空格，使用双引号

变量引用

变量引用用 ${VAR} 语法

命令

`set`

set命令将多变量放在一起。

cmake

set (Foo a b c)

commond(${Foo}) 等价于 command(a b c)
commond("${Foo}") 等价于 command("a b c")

`cmake_minimum_required`

指定运行此配置文件所需的CMake的最低版本。

cmake_minimum_required (VERSION 2.8)

`project`

指定项目信息。

cmake

project (Demo)

`add_executable`

指定生成目标。

cmake

add_executable(Demo demo.cpp)

`aux_source_directory`

查找指定目录下的所有源文件，将结果存进指定变量名。

cmake

aux_source_directory(<dir> <variable>)

cmake

cmake_minimum_required (VERSION 2.8)
project (Demo)
aux_source_directory (. DIR_SRCS)
add_executable(Demo ${DIR_SRCS})

`add_subdirectory`

指明项目包含一个子目录，这样该目录下的CMakeLists.txt文件和源文件也会被处理。

cmake

add_subdirectory(math)

`target_link_libraries`

指明可执行文件需要链接的库。

cmake

target_link_libraries(Demo MathFunctions)

`add_library`

将指定的源文件生成链接文件，然后添加到工程中去

cmake

aux_source_directory(. DIR_LIB_SRCS)
add_library(MathFunctions ${DIR_LIB_SRCS})

`link_directories`

指定连接器查找库的文件夹。此命令的相对路径被解释为相对于当前源目录。

格式

shell

link_directories(directory1 directory2 ...)

示例

cmake

link_directories(${PROJECT_BINARY_DIR}/third_party/googletest/)

`include_directories`

将给定的目录添加到编译器用来搜索头文件的目录中。相对路径被解释为相对于当前源目录。

格式

cmake

include_directories([AFTER|BEFORE] [SYSTEM] dir1 [dir2 ...])

示例

cmake

include_directories(${PROJECT_SOURCE_DIR}/third_party/glog/)
include_directories(${PROJECT_SOURCE_DIR}/third_party/hdfs/)

find_package_handle_standard_args

用于 find_package 的实现。

变量

Cache

cmake

# CACHE, 不覆盖已有值. 
## 用途 
### 1. 在命令行指定变量, 且不被覆盖
set(MY_CACHE_VARIABLE "VALUE" CACHE STRING "Description")

# FORCE, 强制设置
set(MY_CACHE_VARIABLE "VALUE" CACHE STRING "" FORCE)

常用变量

PROJECT_BINARY_DIR
- Full path to build directory for project.
PROJECT_SOURCE_DIR
- Top level source directory for the current project.
CMAKE_CURRENT_SOURCE_DIR
- This the full path to the source directory that is currently being processed by cmake.

Scope

shell

add_subdirectory : 建立新的 scope
include : 不会建立新的 scope
function : 建立新的 scope

示例

shell

bovenson@HP:~/Git/notes/C++/Code/CMake/test$ tree
.
├── CMakeLists.txt
└── t.cpp

0 directories, 2 files
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ cat t.cpp 
#include <iostream>

using namespace std;

int main() {
    cout<<"Hello"<<endl;
    return 0;
}
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ cat CMakeLists.txt 
project("test")
add_executable(Hello t.cpp)
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ cmake .
-- The C compiler identification is GNU 5.4.0
-- The CXX compiler identification is GNU 5.4.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/bovenson/Git/notes/C++/Code/CMake/test
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ tree
.
├── CMakeCache.txt
├── CMakeFiles
│   ├── 3.5.1
│   │   ├── CMakeCCompiler.cmake
│   │   ├── CMakeCXXCompiler.cmake
│   │   ├── CMakeDetermineCompilerABI_C.bin
│   │   ├── CMakeDetermineCompilerABI_CXX.bin
│   │   ├── CMakeSystem.cmake
│   │   ├── CompilerIdC
│   │   │   ├── a.out
│   │   │   └── CMakeCCompilerId.c
│   │   └── CompilerIdCXX
│   │       ├── a.out
│   │       └── CMakeCXXCompilerId.cpp
│   ├── cmake.check_cache
│   ├── CMakeDirectoryInformation.cmake
│   ├── CMakeOutput.log
│   ├── CMakeTmp
│   ├── feature_tests.bin
│   ├── feature_tests.c
│   ├── feature_tests.cxx
│   ├── Hello.dir
│   │   ├── build.make
│   │   ├── cmake_clean.cmake
│   │   ├── DependInfo.cmake
│   │   ├── depend.make
│   │   ├── flags.make
│   │   ├── link.txt
│   │   └── progress.make
│   ├── Makefile2
│   ├── Makefile.cmake
│   ├── progress.marks
│   └── TargetDirectories.txt
├── cmake_install.cmake
├── CMakeLists.txt
├── Makefile
└── t.cpp

6 directories, 31 files
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ make
Scanning dependencies of target Hello
[ 50%] Building CXX object CMakeFiles/Hello.dir/t.cpp.o
[100%] Linking CXX executable Hello
[100%] Built target Hello
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ tree
.
├── CMakeCache.txt
├── CMakeFiles
│   ├── 3.5.1
│   │   ├── CMakeCCompiler.cmake
│   │   ├── CMakeCXXCompiler.cmake
│   │   ├── CMakeDetermineCompilerABI_C.bin
│   │   ├── CMakeDetermineCompilerABI_CXX.bin
│   │   ├── CMakeSystem.cmake
│   │   ├── CompilerIdC
│   │   │   ├── a.out
│   │   │   └── CMakeCCompilerId.c
│   │   └── CompilerIdCXX
│   │       ├── a.out
│   │       └── CMakeCXXCompilerId.cpp
│   ├── cmake.check_cache
│   ├── CMakeDirectoryInformation.cmake
│   ├── CMakeOutput.log
│   ├── CMakeTmp
│   ├── feature_tests.bin
│   ├── feature_tests.c
│   ├── feature_tests.cxx
│   ├── Hello.dir
│   │   ├── build.make
│   │   ├── cmake_clean.cmake
│   │   ├── CXX.includecache
│   │   ├── DependInfo.cmake
│   │   ├── depend.internal
│   │   ├── depend.make
│   │   ├── flags.make
│   │   ├── link.txt
│   │   ├── progress.make
│   │   └── t.cpp.o
│   ├── Makefile2
│   ├── Makefile.cmake
│   ├── progress.marks
│   └── TargetDirectories.txt
├── cmake_install.cmake
├── CMakeLists.txt
├── Hello
├── Makefile
└── t.cpp

6 directories, 35 files
bovenson@HP:~/Git/notes/C++/Code/CMake/test$ ./Hello 
Hello

Data Science

Unraid

docker

k8s

k9s

microk8s

C++

推荐系统

C++

简介 ​

步骤 ​

编译 ​

指定安装路径 ​

指定编译类型 ​

语法 ​

命令 ​

set ​

cmake_minimum_required ​

project ​

add_executable ​

aux_source_directory ​

add_subdirectory ​

target_link_libraries ​

add_library ​

link_directories ​

include_directories ​

find_package_handle_standard_args ​

变量 ​

Cache ​

常用变量 ​

Scope ​

示例 ​

参考 ​

简介

步骤

编译

指定安装路径

指定编译类型

语法

命令

`set`

`cmake_minimum_required`

`project`

`add_executable`

`aux_source_directory`

`add_subdirectory`

`target_link_libraries`

`add_library`

`link_directories`

`include_directories`

find_package_handle_standard_args

变量

Cache

常用变量

Scope

示例

参考