操作系统-进程通信（信号量、匿名管道、命名管道、Socket）

进程通信（信号量、匿名管道、命名管道、Socket）

具体的概念就没必要说了，参考以下链接。

• 信号量
• 匿名管道
• 命名管道
• Socket

Source Code：

1. 信号量（生产者消费者问题）

 #include <iostream>
 #include <Windows.h>
 #include <process.h>
 #include <vector>
 using namespace std;

 #define STD _stdcall  //被调用者负责清栈
 int BufferSize;       //缓冲区大小

 CRITICAL_SECTION CR;  //临界区
 HANDLE Empty = NULL;  //信号量：空闲缓冲区
 HANDLE Full = NULL;   //信号量：满缓冲区
 vector<int>Buffer;    //缓冲区

 /*生产者线程*/
 DWORD STD Producer(void *lp)
 {
     while(true)//自旋测试
     {
         //等待空缓冲区:P(empty)
         WaitForSingleObject(Full, INFINITE);//一直等待
         //进入缓冲区P(mutex)
         EnterCriticalSection(&CR);
         //生产数据
         int s = rand()%;
         Buffer.push_back(s);
         cout << "Producer produces an element : " << s <<endl;
         //退出缓冲区V(mutex)
         LeaveCriticalSection(&CR);
         //增加满缓冲区V(full)
         ReleaseSemaphore(Empty, , NULL);
         //睡一会儿
         Sleep();
     }
 }

 /*消费者线程*/
 DWORD STD Consumer(void *lp)
 {
     while(true)//自旋测试
     {
         //等待满缓冲区:P(empty)
         WaitForSingleObject(Empty, INFINITE);//一直等待
         //进入缓冲区P(mutex)
         EnterCriticalSection(&CR);
         //取出数据
         int r = Buffer[Buffer.size()-];
         Buffer.pop_back();
         cout << "   Consumer consumes an element : " << r <<endl;
         //退出缓冲区V(mutex)
         LeaveCriticalSection(&CR);
         //增加空缓冲区V(full)
         ReleaseSemaphore(Full, , NULL);
         //睡一会儿
         Sleep();
     }
 }

 int main()
 {
     cout << "Input the number of BufferSize : "; cin >> BufferSize;
     //创建信号量
     Empty = CreateSemaphore(NULL, , BufferSize, NULL);
     Full = CreateSemaphore(NULL, BufferSize, BufferSize,NULL);

     //初始化临界区
     InitializeCriticalSection(&CR);

     int pNum, cNum;
     cout << "Input the number of Producer(Max:10) : "; cin >> pNum;
     cout << "Input the number of Consumer(Max:10) : "; cin >> cNum;

     //创建线程
     int i;
     HANDLE handle[];
     for(i=; i<pNum; i++)
     {
         handle[i] = CreateThread(, , &Producer, , , );
     }
     for(i=pNum; i<pNum+cNum; i++)
     {
         handle[i] = CreateThread(, , &Consumer, , , );
     }

     //回收线程
     WaitForMultipleObjects(pNum+cNum, handle, true, INFINITE);

     //释放线程
     for(i=; i<pNum+cNum; i++)
     {
         CloseHandle(handle[]);
     }

     //释放缓冲区
     DeleteCriticalSection(&CR);
     return ;
 }

结果：

2. 匿名管道（本地父进程与子进程通信）

原理：

源码：

 /*
 *匿名管道：父子进程通信
 *date : 2018/12/3
 *author : yocichen
 *status : Done
 */
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 int main()
 {
     //pipe1 p to s, pipe2 s to p
     int fd_1[], fd_2[];

     if(pipe(fd_1)< || pipe(fd_2)<)//fail to create pipe
     {
         printf("Fail to create the pipe.\n");
         return -;
     }

     char buf[];//
     const char *temp;

     //child
     int fork_result = fork();
     if(fork_result == )
     {
         close(fd_1[]);//close read port
         close(fd_2[]);//close write port

         //read message
         read(fd_1[], buf, sizeof(buf));//read message from father port
         printf("\nChild  : receive a message from pipe1: %s\n", buf);

         //write message
         temp = "Hi, my parent, I love you too.";
         write(fd_2[], temp, strlen(temp));//child write message to pipe2
     }

     else
     {
         close(fd_2[]);
         close(fd_1[]);

         //write message
         temp = "My child, I love you.";
         write(fd_1[], temp, strlen(temp));//parent write message to pipe1

         //read message
         read(fd_2[], buf, sizeof(buf));//read message from pipe2
         printf("\nParent : receive a message from pipe2: %s\n", buf);
     }
     return ;
 }

（注意：该匿名管道程序为Linux系统开发，注意运行环境，windows下使用CodeBlocks可以运行）

3.命名管道

原理：

源码：

 #include <windows.h>
 #include <stdio.h>
 #include <stdlib.h>

 int main()
 {
     //创建命名管道
     HANDLE namedPipe = CreateNamedPipeA("\\\\.\\pipe\\testName", PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED, PIPE_TYPE_BYTE, , , , , NULL);

     //校验状态
     if(namedPipe == INVALID_HANDLE_VALUE)
     {
         printf("Server: Fail to create named pipe.\n");
     }
     else
     {
         printf("Server: Succeed to create pipe.\n");
     }

     OVERLAPPED op;
     ZeroMemory(&op, sizeof(OVERLAPPED));

     //创建事件对象
     op.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

     //等待连接
     bool b = ConnectNamedPipe(namedPipe, &op);
     printf("Server: Listen...\n");

     int status = WaitForSingleObject(op.hEvent, INFINITE);
     //连接成功
     if(status == )
     {
         printf("Server: Succeed to connect.\n");
     }
     else
     {
         printf("Server: Fail to connect.\n");
     }

     //通信
     char buf[] = "来玩个猜数游戏吧！\n";
     DWORD wp;
     WriteFile(namedPipe, buf, strlen(buf), &wp, NULL);

     int ans = rand()%+;
     while(status == )
     {
         ZeroMemory(buf, );
         ReadFile(namedPipe, buf, , &wp, NULL);
         printf("收到：%s\n", buf);

         if(int(buf[] - '') < ans)
         {
             WriteFile(namedPipe, "小了，再猜一次!\n", strlen("小了，再猜一次！\n"), &wp, NULL);
         }
         else if((buf[]-'') > ans)
         {
             WriteFile(namedPipe, "大了，再猜一次!\n", strlen("大了，再猜一次！\n"), &wp, NULL);
         }
         else
         {
             WriteFile(namedPipe, "猜对了！\n", strlen("小了，再猜一次！\n"), &wp, NULL);
             break;
         }

         if(buf[] == '')
         {
             printf("客户已退出！\n");
             break;
         }
     }

     //通信结束
     DisconnectNamedPipe(namedPipe);
     return ;
 }

Server

 #include <windows.h>
 #include <stdio.h>
 #include <stdlib.h>

 int main()
 {
     //检查管道是否存在
     bool b = WaitNamedPipeA("\\\\.\\pipe\\testName", );

     //打开管道
     HANDLE hFile = CreateFileA("\\\\.\\pipe\\testName", GENERIC_READ | GENERIC_WRITE, , NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

     //是否连接成功
     if(b == || hFile == INVALID_HANDLE_VALUE)
     {
         printf("Client: fail to connect.\n");
         return ;
     }
     else
     {
         printf("Client: Succeed to connect.\n");
     }

     //通信
     char buf[];
     ZeroMemory(buf, );
     DWORD rp;
     ReadFile(hFile, buf, , &rp, NULL);//读取
     printf(buf);

     while(true)
     {
         printf("输入数字：");
         scanf("%s", buf);
         WriteFile(hFile, buf, strlen(buf), &rp, NULL);

         while(ReadFile(hFile, buf, , &rp, NULL) == true)
         {
             printf("Server: ");
             printf(buf);
             break;
         }
     }

     CloseHandle(hFile);
     return ;
 }

Client

4.Socket网络进程通信

原理：

源码：

 /*注意头文件顺序*/
 #include <winsock2.h>
 #include <stdio.h>
 #include <stdlib.h>
 #pragma comment(lib, "ws2_32.lib")      //引入动态链接库

 int main()
 {
     WORD ws_version = MAKEWORD(, );   //指定Winsock version
     WSADATA wsaData;                    //WSA 函数的参数

     /*初始化winsock*/
     WSAStartup(ws_version, &wsaData);

     /*socket*/
     SOCKET s_server = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

     SOCKADDR_IN addr_server;
     addr_server.sin_family = AF_INET;   //协议
     addr_server.sin_port = htons(); //端口
     addr_server.sin_addr.s_addr = htonl(INADDR_ANY);    //IP:任意IP

     /*bind*/
     int bind_status;
     bind_status = bind(s_server, (SOCKADDR*)&addr_server, sizeof(SOCKADDR));
     if(bind_status == SOCKET_ERROR)
     {
         printf("bind error : fail to bind! \n");
     }
     else
     {
         printf("bind successfully!\n");
     }

     /*listen*/
     listen(s_server, );//max=5
     printf("listening ... \n");

     SOCKADDR_IN addr_client;            //存储client地址信息
     int len = sizeof(SOCKADDR);
     int count = ;                        //统计客户数目
     SOCKET s_client;                    //连接的socket

     char buf[];
     while(true)
     {
         printf("等待客户端连接...\n");
         /*accept*/
         s_client = accept(s_server, (SOCKADDR*)&addr_client, &len);
         if(s_client == INVALID_SOCKET)
         {
             printf("Accept error : fail to accept client! ");
         }
         else//连接成功
         {
             count++;
             printf("\nAccept successfully!\n");

             printf("---------------------------------------------\n");
             printf(" 编号：%d \n", count);
             printf(" Port：%d\n", ntohs(addr_client.sin_port));
             printf(" IP：%s\n", inet_ntoa(addr_client.sin_addr));//inet_ntoa(SOCKADDR.in_addr)网络地址转换为IP

             int recv_status = recv(s_client, buf, , );
             if(recv_status > )
             {
                 printf("收到：");
                 buf[recv_status] = 0x00;//截断
                 printf(buf);
                 printf("\n---------------------------------------------\n");
             }
             const char *sendData = "你好!客户端!我是服务器";
             send(s_client, sendData, strlen(sendData), );
             closesocket(s_client);
         }
     }

     closesocket(s_server);      //关闭socket
     WSACleanup();

     return ;
 }

Server

 #include <winsock2.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <windows.h>
 #include <iostream>
 #pragma comment(lib, "ws2_32.lib")      //引入动态链接库
 #define SERVER_IP "192.168.31.102"        //客户端IP
 using namespace std;

 int main()
 {
     WORD ws_version = MAKEWORD(, );   //指定Winsock version
     WSADATA wsaData;                    //WSA 函数的参数

     /*初始化winsock*/
     WSAStartup(ws_version, &wsaData);

     while(true)
     {
         /*socket*/
         SOCKET s_client = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

         SOCKADDR_IN addr_server;
         addr_server.sin_family = AF_INET;   //协议
         addr_server.sin_port = htons(); //端口
         addr_server.sin_addr.s_addr = inet_addr(SERVER_IP);

         char buf[];
         int send_status, recv_status;

         /*Connect*/
         int cnct_status = connect(s_client, (SOCKADDR*)&addr_server, sizeof(SOCKADDR));
         if(cnct_status == )//连接成功
         {
                 printf("\nConnecting... done\n");

                 //向服务端发送消息
                 printf("输入发送信息：");
                 scanf("%s", buf);
                 send_status = send(s_client, buf, , );
                 if(send_status == SOCKET_ERROR)//发送失败
                 {
                     printf("send error!\n");
                 }
                 else
                 {
                     printf("发送：%s\n", buf);
                     //接受服务端消息
                     recv_status = recv(s_client, buf, , );
                     buf[recv_status] = 0x00;//截断
                     printf("收到：%s\n", buf);
                 }
         }
         else
         {
             printf("Test:fail to connect server! \n");
         }
         closesocket(s_client);
     }

     WSACleanup();

     return ;
 }

Client