Ubuntu VScode C++ 编译、引用.so--多项目编译+解決No such file or directory问题

1.Ubuntu VScode C++配置

參考：

https://blog.youkuaiyun.com/weixin_43374723/article/details/84064644

https://blog.youkuaiyun.com/wangxiao7474/article/details/103164235

 

2. 编译、引用.so

2.1 新建项目 

```
buildSo
├─ .vscode
│  ├─ c_cpp_properties.json
│  ├─ launch.json
│  └─ tasks.json
├─ common
│  ├─ include
│  │  ├─ a.h
│  │  ├─ b.h
│  │  └─ c.h
│  └─ src
│     ├─ a.cpp
│     ├─ b.cpp
│     └─ c.cpp
├─ lib
│  └─ callso
├─ testDemo
│  ├─ buildso.cpp
│  └─ callso.cpp
└─ utils
   └─ buildso
      ├─ include
      │  └─ buildso.h
      └─ lib
         └─ libbuildso.so

//a.h
#include "stdio.h"
void test_a();

//b.h
#include "stdio.h"
void test_b();

//c.h
#include "stdio.h"
void test_c();

//a.cpp：
#include "a.h"
void test_a()
{
    printf("this is in test_a...\n");
}

//b.cpp：
#include "b.h"
void test_b()
{
    printf("this is in test_b...\n");
}

//c.cpp：
#include "c.h"
void test_c()
{
    printf("this is in test_c...\n");
}

//buildso.h：
#include "stdio.h"
#include "a.h"
#include "b.h"
#include "c.h"
void test_buildso();

//buildso.cpp：
#include "buildso.h"
void test_buildso()
{
    test_a();
    test_b();
    test_c();
    printf("this is in test_buildso...\n");
}

//callso.cpp
#include "stdio.h"
#include "buildso.h"
int main()
{
    test_buildso();
    test_a();
}

 

2.2 修改编译、引用.so 的配置文件

（1）Ctrl+shift+D --> 点击运行和调试 --> 选择"C++（GDB/LLDB）" --> 选择“g++ -生成和调试活动文件“ --> 生成“launch.json”和“tasks.json”文件；

（2）Ctrl+Shift+P --> 打开搜索框，键入c++ --> 选择“Edit configurations (JSON)“ --> 生成“c_cpp_properties.json”；

參考：https://blog.youkuaiyun.com/cdknight_happy/article/details/106574300

task.json:

// ************buildso,生成so包时的配置文件*************
{
    "tasks": [
        {
            "type": "cppbuild",
            "label": "C/C++: g++ build active file",
            "command": "/usr/bin/g++",
            "args": [
                "-g","-std=c++11",
                "${workspaceFolder}/common/src/*.cpp",           //so包函数实现的文件
                "${workspaceFolder}/testDemo/buildso.cpp",
                "-o",
                "${workspaceFolder}/utils/buildso/lib/libbuildso.so",  //生成的包一定要是lib+包名+.so的形式
                "-fPIC",                                         //生成和位置无关的so文件
                "-shared",							             //生成动态链接库，即so文件
                "-I", "${workspaceFolder}/common/include",
                "-I", "${workspaceFolder}/utils/buildso/include"
            ],
            "options": {
                "cwd": "${workspaceFolder}"
            },
            "problemMatcher": [
                "$gcc"
            ],
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "detail": "Task generated by Debugger."
        }
    ],
    "version": "2.0.0"
}

// ************callso,调用so包时的配置文件*************
/*
{
    "tasks": [
        {
            "type": "cppbuild",
            "label": "C/C++: g++ build active file",
            "command": "/usr/bin/g++",
            "args": [
                "-g","-std=c++11",          
                "${workspaceFolder}/testDemo/callso.cpp",               //so包函数实现的文件
                "-o",
                "${workspaceFolder}/lib/${fileBasenameNoExtension}",
                "-I", "${workspaceFolder}/utils/buildso/include",
                "-I", "${workspaceFolder}/common/include",
                "-L", "${workspaceFolder}/utils/buildso/lib",	   //库文件路径，多个路径时逗号分割
                "-l", "buildso"                                    //具体的库文件，这里是指libhello.so
            ],
            "options": {
                "cwd": "${workspaceFolder}"
            },
            "problemMatcher": [
                "$gcc"
            ],
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "detail": "Task generated by Debugger."
        }
    ],
    "version": "2.0.0"
}
*/

fPIC的含义，请参考：https://www.cnblogs.com/fengliu-/p/10216878.html
shared的含义，请参考：https://www.cnblogs.com/ziyunlong/p/6023121.html，就是创建动态链接库，对应于windows下的dll，所以在运行程序的时候的时候要通过系统的环境变量能找到对应的so文件。

lauch.json:

// ************buildso,生成so包时的配置文件*************
{
    // 使用 IntelliSense 了解相关属性。 
    // 悬停以查看现有属性的描述。
    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "g++ - 生成和调试活动文件",
            "type": "cppdbg",
            "request": "launch",    
            "program": "{workspaceFolder}/utils/buildso/lib/libbuildso.so",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "为 gdb 启用整齐打印",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "C/C++: g++ build active file",
            "miDebuggerPath": "/usr/bin/gdb"
        }
    ]
}

// ************callso,调用so包时的配置文件*************
/*
{
    // 使用 IntelliSense 了解相关属性。 
    // 悬停以查看现有属性的描述。
    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "g++ - 生成和调试活动文件",
            "type": "cppdbg",
            "request": "launch",
            "program": "${workspaceFolder}/lib/${fileBasenameNoExtension}",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "为 gdb 启用整齐打印",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "C/C++: g++ build active file",
            "miDebuggerPath": "/usr/bin/gdb"
        }
    ]
}
*/

c_cpp_properties.json:

// ************buildso,生成so包时的配置文件*************
{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/common/include",
                "${workspaceFolder}/utils/buildso/include"    
            ],
            "defines": [],
            "compilerPath": "/usr/bin/gcc",
            "cStandard": "gnu17",
            "cppStandard": "gnu++14",
            "intelliSenseMode": "gcc-x64"
        }
    ],
    "version": 4
}

// ************callso,调用so包时的配置文件*************
/*
{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/utils/buildso/include",
                "${workspaceFolder}/common/include"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/gcc",
            "cStandard": "gnu17",
            "cppStandard": "gnu++14",
            "intelliSenseMode": "gcc-x64"
        }
    ],
    "version": 4
}
*/

 

2.3 配置Linux动态链接库搜索路径

编译生成.so文件之后， 引用.so，若直接F5运行，会出现如下问题：

/home/morgandas/VScodeProjects/testSo/lib/main: error while loading shared libraries: libhello.so: cannot open shared object file: No such file or directory

解决办法：

參考：https://blog.youkuaiyun.com/yjk13703623757/article/details/53217377

1.将用户用到的库统一放到一个目录，如 /usr/loca/lib/vscodeDevelop
# cp libXXX.so.X /usr/loca/lib/vscodeDevelop           

2.向库配置文件中，写入库文件所在目录
# vim /etc/ld.so.conf.d/usr-libs.conf    
  /usr/local/lib/vscodeDevelop  

3.更新/etc/ld.so.cache文件
# ldconfig  

4. 重启系统生效

采用这种办法，对于原系统的改动也最小。而/etc/ld.so.conf的文件内容是include /etc/ld.so.conf.d/*.conf，所以在/etc/ld.so.conf.d目录下，加入任何以.conf为后缀的文件，都能被ld识别。

2.4  测试

按F5运行，调用成功。

this is in test_a...
this is in test_b...
this is in test_c...
this is in test_buildso...

this is in test_a...