cmake——效率高跨平台的makefile生成神器

在 linux 平台下使用 CMake 生成 Makefile 并编译的流程如下:
1、编写 CmakeLists.txt。
2、执行命令“cmake PATH”或者“ccmake PATH”生成 Makefile ( PATH 是 CMakeLists.txt 所在的目录 )。

3、使用 make 命令进行编译。

1、单源文件目录

zjy@ubuntu:~/cmkTest$ ls

CMakeLists.txt  main.cc

zjy@ubuntu:~/cmkTest$ cat main.cc 

#include<iostream>

int main()

{

std::cout<<"hello"<<std::endl;

return 0;

}

zjy@ubuntu:~/cmkTest$ cat CMakeLists.txt 

CMAKE_MINIMUM_REQUIRED(VERSION 2.6)

PROJECT(main)

AUX_SOURCE_DIRECTORY(. DIR_SRCS)

ADD_EXECUTABLE(main ${DIR_SRCS})

zjy@ubuntu:~/cmkTest$ 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/zjy/cmkTest

zjy@ubuntu:~/cmkTest$ ls

CMakeCache.txt  cmake_install.cmake  main.cc

CMakeFiles      CMakeLists.txt       Makefile

zjy@ubuntu:~/cmkTest$ make

Scanning dependencies of target main

[ 50%] Building CXX object CMakeFiles/main.dir/main.cc.o

[100%] Linking CXX executable main

[100%] Built target main

zjy@ubuntu:~/cmkTest$ ls

CMakeCache.txt  cmake_install.cmake  main     Makefile

CMakeFiles      CMakeLists.txt       main.cc

zjy@ubuntu:~/cmkTest$ ./main 

hello

zjy@ubuntu:~/cmkTest$ 

CMakeLists.txt:

关键字正确显示橙色，错误显示黑色。

CMAKE_MINIMUM_REQUIRED(VERSION 2.6)——限定了最小版本是2.6

PROJECT(main)——设置生成执行文件的名字为main

AUX_SOURCE_DIRECTORY(. DIR_SRCS)——将源文件目录赋值给变量DIR_SRCS，原型是aux_source_directory(<dir> <variable>)

ADD_EXECUTABLE(main ${DIR_SRCS})——将变量 DIR_SRCS 中的源文件需要编译成一个名称为 main 的可执行文件

2、多源文件目录

zjy@ubuntu:~$ tree cmkTest/

cmkTest/

├── CMakeLists.txt

├── main

├── main.cc

└── print

    ├── CMakeLists.txt

    ├── print.cc

    └── print.h

1 directory, 6 files

zjy@ubuntu:~$ cd cmkTest/

zjy@ubuntu:~/cmkTest$ ls

CMakeLists.txt  main  main.cc print

zjy@ubuntu:~/cmkTest$ cat CMakeLists.txt 

CMAKE_MINIMUM_REQUIRED(VERSION 2.6)

PROJECT(main)

add_subdirectory( print )

AUX_SOURCE_DIRECTORY(. DIR_SRCS)

ADD_EXECUTABLE(main ${DIR_SRCS})

target_link_libraries( main print)

zjy@ubuntu:~/cmkTest$ cat print/CMakeLists.txt 

AUX_SOURCE_DIRECTORY(. DIR_PRINT_SRCS)

add_library(print ${DIR_PRINT_SRCS})

zjy@ubuntu:~/cmkTest$ cat print/print.cc 

#include<iostream>

#include"print.h"

void print()

{

std::cout<<"hello"<<std::endl;

}

zjy@ubuntu:~/cmkTest$ 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/zjy/cmkTest

zjy@ubuntu:~/cmkTest$ make

Scanning dependencies of target print

[ 25%] Building CXX object print/CMakeFiles/print.dir/print.cc.o

[ 50%] Linking CXX static library libprint.a

[ 50%] Built target print

Scanning dependencies of target main

[ 75%] Building CXX object CMakeFiles/main.dir/main.cc.o

[100%] Linking CXX executable main

[100%] Built target main

zjy@ubuntu:~/cmkTest$ ls -lh

total 52K

-rw-rw-r-- 1 zjy zjy  12K Aug  2 16:49 CMakeCache.txt

drwxrwxr-x 5 zjy zjy 4.0K Aug  2 16:49 CMakeFiles

-rw-rw-r-- 1 zjy zjy 1.5K Aug  2 16:49 cmake_install.cmake

-rw-rw-r-- 1 zjy zjy  177 Aug  2 16:40 CMakeLists.txt

-rwxrwxr-x 1 zjy zjy 9.2K Aug  2 16:49 main

-rw-rw-r-- 1 zjy zjy  112 Aug  2 16:36 main.cc

-rw-rw-r-- 1 zjy zjy 5.0K Aug  2 16:49 Makefile

drwxrwxr-x 3 zjy zjy 4.0K Aug  2 16:49 print

zjy@ubuntu:~/cmkTest$ ./main 

hello

hello

zjy@ubuntu:~/cmkTest$ 

/CMakeLists.txt:

CMAKE_MINIMUM_REQUIRED(VERSION 2.6)

PROJECT(main)

add_subdirectory( print )——增加一个子目录

AUX_SOURCE_DIRECTORY(. DIR_SRCS)

ADD_EXECUTABLE(main ${DIR_SRCS})

target_link_libraries( main print)——main需要一个print链接库

/print/MakeLists.txt:

AUX_SOURCE_DIRECTORY(. DIR_PRINT_SRCS)

add_library(print ${DIR_PRINT_SRCS})——增加一个print链接库

在根目录下执行"cmake ."，先解析根目录下的MakeLists.txt，遇到add_subdirectory( print )后进入print目录解析/print/MakeLists.txt。

其他常用命令汇总：

include_directories(${PROJECT_SOURCE_DIR}/print)——main目录与print目录在同一层，PROJECT_SOURCE_DIR代表根目录
target_link_libraries(main print) ——执行文件main链接print链接库

set(LIB_SRC hello.c) ——设置变量set(LIB_SRC hello.c hello2.c)
add_library(libhello ${LIB_SRC})
set_target_properties(libhello PROPERTIES OUTPUT_NAME "hello")——文件是hello.c如果与外面名字有冲突，可以修改为libhello

set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)——设置执行文件输出目录
set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib) ——设置库文件输出目录