socket多人聊天程序C語言版(一)
本文實例為大家分享了C語言實現(xiàn)socket多人聊天程序的第一篇,供大家參考,具體內(nèi)容如下
首先,不要一步登天直接解決多人聊天這個問題,先把問題化簡。
1.多人聊天的核心問題是服務(wù)器如何標識不同的客戶端,如何根據(jù)客戶端的需求轉(zhuǎn)發(fā)消息給指定客戶端。
2.多人聊天轉(zhuǎn)化為C-C聊天,但是不再是直接C-C,而是通過server轉(zhuǎn)發(fā)消息,所以變成==>C-S-C。
3.server如何允許2個client同時連接,設(shè)置listen函數(shù)的第二個參數(shù),最大連接數(shù)。
4.server如何標識兩個client,用一個結(jié)構(gòu)體數(shù)組來存放兩個client的信息。
5.server如何轉(zhuǎn)發(fā)消息給client,很簡單,先接收到的發(fā)送給還沒接收到的。如圖:
6.server如何管理兩個client的連接狀態(tài),連接成功很簡單,就是accpet成功后就是連接成功了。但是怎么判斷連接斷開呢?這個涉及到的select函數(shù)的使用,有點復雜~,所以我就簡單的用了一個send函數(shù)發(fā)送一個空消息來判斷是否斷開連接,這個不嚴謹,容易出BUG,但是實踐起來簡單就使用了它。
7.要用線程來管理接收消息、發(fā)送消息、接受請求、管理連接狀態(tài)。
技術(shù)要點:C語言線程函數(shù)的使用。
_beginthreadex函數(shù)原型 _ACRTIMP uintptr_t __cdecl _beginthreadex ( _In_opt_ void* _Security,//安全屬性,NULL為默認安全屬性 _In_ unsigned _StackSize,//線程堆棧的大小。如果為0,則線程堆棧大小和創(chuàng)建它的線程的相同。一般用0 _In_ _beginthreadex_proc_type _StartAddress, //線程函數(shù)的地址 _In_opt_ void* _ArgList, //傳進線程的函數(shù) _In_ unsigned _InitFlag, //線程初始狀態(tài),0:立即運行;CREATE_SUSPEND:懸掛(如果出事狀態(tài)定義為懸掛,就要調(diào)用ResumeThread(HANDLE) 來激活線程的運行) _Out_opt_ unsigned* _ThrdAddr //用于記錄線程ID的地址 )
例子:
#include <process.h> #include <stdio.h> unsigned __stdcall Thread(void* param) { printf("%d\n", *(int*)param); //這里必須先要強行轉(zhuǎn)換為int*,不然void* 直接解引用會出錯。 return 0; } int main() { int i = 0; _beginthreadex(NULL, 0, Thread, &i, 0, NULL); return 0; }
1V1,C-S-C聊天例子:
編寫環(huán)境:win10,VS2015
效果圖:
server code:
#include <WinSock2.h> #include <process.h> #include <stdio.h> #include <stdlib.h> #pragma comment(lib,"ws2_32.lib") #define SEND_OVER 1 //已經(jīng)轉(zhuǎn)發(fā)消息 #define SEND_YET 0 //還沒轉(zhuǎn)發(fā)消息 int g_iStatus = SEND_YET; SOCKET g_ServerSocket = INVALID_SOCKET; //服務(wù)端套接字 SOCKADDR_IN g_ClientAddr = { 0 }; //客戶端地址 int g_iClientAddrLen = sizeof(g_ClientAddr); bool g_bCheckConnect = false; //檢查連接情況 HANDLE g_hRecv1 = NULL; HANDLE g_hRecv2 = NULL; //客戶端信息結(jié)構(gòu)體 typedef struct _Client { SOCKET sClient; //客戶端套接字 char buf[128]; //數(shù)據(jù)緩沖區(qū) char userName[16]; //客戶端用戶名 char IP[20]; //客戶端IP UINT_PTR flag; //標記客戶端,用來區(qū)分不同的客戶端 }Client; Client g_Client[2] = { 0 }; //創(chuàng)建一個客戶端結(jié)構(gòu)體 //發(fā)送數(shù)據(jù)線程 unsigned __stdcall ThreadSend(void* param) { int ret = 0; int flag = *(int*)param; SOCKET client = INVALID_SOCKET; //創(chuàng)建一個臨時套接字來存放要轉(zhuǎn)發(fā)的客戶端套接字 char temp[128] = { 0 }; //創(chuàng)建一個臨時的數(shù)據(jù)緩沖區(qū),用來存放接收到的數(shù)據(jù) memcpy(temp, g_Client[!flag].buf, sizeof(temp)); sprintf(g_Client[flag].buf, "%s: %s", g_Client[!flag].userName, temp);//添加一個用戶名頭 if (strlen(temp) != 0 && g_iStatus == SEND_YET) //如果數(shù)據(jù)不為空且還沒轉(zhuǎn)發(fā)則轉(zhuǎn)發(fā) ret = send(g_Client[flag].sClient, g_Client[flag].buf, sizeof(g_Client[flag].buf), 0); if (ret == SOCKET_ERROR) return 1; g_iStatus = SEND_OVER; //轉(zhuǎn)發(fā)成功后設(shè)置狀態(tài)為已轉(zhuǎn)發(fā) return 0; } //接受數(shù)據(jù) unsigned __stdcall ThreadRecv(void* param) { SOCKET client = INVALID_SOCKET; int flag = 0; if (*(int*)param == g_Client[0].flag) //判斷是哪個客戶端發(fā)來的消息 { client = g_Client[0].sClient; flag = 0; } else if (*(int*)param == g_Client[1].flag) { client = g_Client[1].sClient; flag = 1; } char temp[128] = { 0 }; //臨時數(shù)據(jù)緩沖區(qū) while (1) { memset(temp, 0, sizeof(temp)); int ret = recv(client, temp, sizeof(temp), 0); //接收數(shù)據(jù) if (ret == SOCKET_ERROR) continue; g_iStatus = SEND_YET; //設(shè)置轉(zhuǎn)發(fā)狀態(tài)為未轉(zhuǎn)發(fā) flag = client == g_Client[0].sClient ? 1 : 0; //這個要設(shè)置,否則會出現(xiàn)自己給自己發(fā)消息的BUG memcpy(g_Client[!flag].buf, temp, sizeof(g_Client[!flag].buf)); _beginthreadex(NULL, 0, ThreadSend, &flag, 0, NULL); //開啟一個轉(zhuǎn)發(fā)線程,flag標記著要轉(zhuǎn)發(fā)給哪個客戶端 //這里也可能是導致CPU使用率上升的原因。 } return 0; } //管理連接 unsigned __stdcall ThreadManager(void* param) { while (1) { if (send(g_Client[0].sClient, "", sizeof(""), 0) == SOCKET_ERROR) { if (g_Client[0].sClient != 0) { CloseHandle(g_hRecv1); //這里關(guān)閉了線程句柄,但是測試結(jié)果斷開連C/S接后CPU仍然瘋漲 CloseHandle(g_hRecv2); printf("Disconnect from IP: %s,UserName: %s\n", g_Client[0].IP, g_Client[0].userName); closesocket(g_Client[0].sClient); //這里簡單的判斷:若發(fā)送消息失敗,則認為連接中斷(其原因有多種),關(guān)閉該套接字 g_Client[0] = { 0 }; } } if (send(g_Client[1].sClient, "", sizeof(""), 0) == SOCKET_ERROR) { if (g_Client[1].sClient != 0) { CloseHandle(g_hRecv1); CloseHandle(g_hRecv2); printf("Disconnect from IP: %s,UserName: %s\n", g_Client[1].IP, g_Client[1].userName); closesocket(g_Client[1].sClient); g_Client[1] = { 0 }; } } Sleep(2000); //2s檢查一次 } return 0; } //接受請求 unsigned __stdcall ThreadAccept(void* param) { int i = 0; int temp1 = 0, temp2 = 0; _beginthreadex(NULL, 0, ThreadManager, NULL, 0, NULL); while (1) { while (i < 2) { if (g_Client[i].flag != 0) { ++i; continue; } //如果有客戶端申請連接就接受連接 if ((g_Client[i].sClient = accept(g_ServerSocket, (SOCKADDR*)&g_ClientAddr, &g_iClientAddrLen)) == INVALID_SOCKET) { printf("accept failed with error code: %d\n", WSAGetLastError()); closesocket(g_ServerSocket); WSACleanup(); return -1; } recv(g_Client[i].sClient, g_Client[i].userName, sizeof(g_Client[i].userName), 0); //接收用戶名 printf("Successfuuly got a connection from IP:%s ,Port: %d,UerName: %s\n", inet_ntoa(g_ClientAddr.sin_addr), htons(g_ClientAddr.sin_port), g_Client[i].userName); memcpy(g_Client[i].IP, inet_ntoa(g_ClientAddr.sin_addr), sizeof(g_Client[i].IP)); //記錄客戶端IP g_Client[i].flag = g_Client[i].sClient; //不同的socke有不同UINT_PTR類型的數(shù)字來標識 i++; } i = 0; if (g_Client[0].flag != 0 && g_Client[1].flag != 0) //當兩個用戶都連接上服務(wù)器后才進行消息轉(zhuǎn)發(fā) { if (g_Client[0].flag != temp1) //每次斷開一個連接后再次連上會新開一個線程,導致cpu使用率上升,所以要關(guān)掉舊的 { if (g_hRecv1) //這里關(guān)閉了線程句柄,但是測試結(jié)果斷開連C/S接后CPU仍然瘋漲 CloseHandle(g_hRecv1); g_hRecv1 = (HANDLE)_beginthreadex(NULL, 0, ThreadRecv, &g_Client[0].flag, 0, NULL); //開啟2個接收消息的線程 } if (g_Client[1].flag != temp2) { if (g_hRecv2) CloseHandle(g_hRecv2); g_hRecv2 = (HANDLE)_beginthreadex(NULL, 0, ThreadRecv, &g_Client[1].flag, 0, NULL); } } temp1 = g_Client[0].flag; //防止ThreadRecv線程多次開啟 temp2 = g_Client[1].flag; Sleep(3000); } return 0; } //啟動服務(wù)器 int StartServer() { //存放套接字信息的結(jié)構(gòu) WSADATA wsaData = { 0 }; SOCKADDR_IN ServerAddr = { 0 }; //服務(wù)端地址 USHORT uPort = 18000; //服務(wù)器監(jiān)聽端口 //初始化套接字 if (WSAStartup(MAKEWORD(2, 2), &wsaData)) { printf("WSAStartup failed with error code: %d\n", WSAGetLastError()); return -1; } //判斷版本 if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2) { printf("wVersion was not 2.2\n"); return -1; } //創(chuàng)建套接字 g_ServerSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (g_ServerSocket == INVALID_SOCKET) { printf("socket failed with error code: %d\n", WSAGetLastError()); return -1; } //設(shè)置服務(wù)器地址 ServerAddr.sin_family = AF_INET;//連接方式 ServerAddr.sin_port = htons(uPort);//服務(wù)器監(jiān)聽端口 ServerAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);//任何客戶端都能連接這個服務(wù)器 //綁定服務(wù)器 if (SOCKET_ERROR == bind(g_ServerSocket, (SOCKADDR*)&ServerAddr, sizeof(ServerAddr))) { printf("bind failed with error code: %d\n", WSAGetLastError()); closesocket(g_ServerSocket); return -1; } //設(shè)置監(jiān)聽客戶端連接數(shù) if (SOCKET_ERROR == listen(g_ServerSocket, 20000)) { printf("listen failed with error code: %d\n", WSAGetLastError()); closesocket(g_ServerSocket); WSACleanup(); return -1; } _beginthreadex(NULL, 0, ThreadAccept, NULL, 0, 0); for (int k = 0;k < 100;k++) //讓主線程休眠,不讓它關(guān)閉TCP連接. Sleep(10000000); //關(guān)閉套接字 for (int j = 0;j < 2;j++) { if (g_Client[j].sClient != INVALID_SOCKET) closesocket(g_Client[j].sClient); } closesocket(g_ServerSocket); WSACleanup(); return 0; } int main() { StartServer(); //啟動服務(wù)器 return 0; }
client code:
#define _WINSOCK_DEPRECATED_NO_WARNINGS #include <WinSock2.h> #include <process.h> #include <stdio.h> #include <stdlib.h> #include <conio.h> #pragma comment(lib,"ws2_32.lib") #define RECV_OVER 1 #define RECV_YET 0 char userName[16] = { 0 }; int iStatus = RECV_YET; //接受數(shù)據(jù) unsigned __stdcall ThreadRecv(void* param) { char buf[128] = { 0 }; while (1) { int ret = recv(*(SOCKET*)param, buf, sizeof(buf), 0); if (ret == SOCKET_ERROR) { Sleep(500); continue; } if (strlen(buf) != 0) { printf("%s\n", buf); iStatus = RECV_OVER; } else Sleep(100); } return 0; } //發(fā)送數(shù)據(jù) unsigned __stdcall ThreadSend(void* param) { char buf[128] = { 0 }; int ret = 0; while (1) { int c = getch(); if(c == 72 || c == 0 || c == 68)//為了顯示美觀,加一個無回顯的讀取字符函數(shù) continue; //getch返回值我是經(jīng)過實驗得出如果是返回這幾個值,則getch就會自動跳過,具體我也不懂。 printf("%s: ", userName); gets_s(buf); ret = send(*(SOCKET*)param, buf, sizeof(buf), 0); if (ret == SOCKET_ERROR) return 1; } return 0; } //連接服務(wù)器 int ConnectServer() { WSADATA wsaData = { 0 };//存放套接字信息 SOCKET ClientSocket = INVALID_SOCKET;//客戶端套接字 SOCKADDR_IN ServerAddr = { 0 };//服務(wù)端地址 USHORT uPort = 18000;//服務(wù)端端口 //初始化套接字 if (WSAStartup(MAKEWORD(2, 2), &wsaData)) { printf("WSAStartup failed with error code: %d\n", WSAGetLastError()); return -1; } //判斷套接字版本 if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2) { printf("wVersion was not 2.2\n"); return -1; } //創(chuàng)建套接字 ClientSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (ClientSocket == INVALID_SOCKET) { printf("socket failed with error code: %d\n", WSAGetLastError()); return -1; } //輸入服務(wù)器IP printf("Please input server IP:"); char IP[32] = { 0 }; gets_s(IP); //設(shè)置服務(wù)器地址 ServerAddr.sin_family = AF_INET; ServerAddr.sin_port = htons(uPort);//服務(wù)器端口 ServerAddr.sin_addr.S_un.S_addr = inet_addr(IP);//服務(wù)器地址 printf("connecting......\n"); //連接服務(wù)器 if (SOCKET_ERROR == connect(ClientSocket, (SOCKADDR*)&ServerAddr, sizeof(ServerAddr))) { printf("connect failed with error code: %d\n", WSAGetLastError()); closesocket(ClientSocket); WSACleanup(); return -1; } printf("Connecting server successfully IP:%s Port:%d\n", IP, htons(ServerAddr.sin_port)); printf("Please input your UserName: "); gets_s(userName); send(ClientSocket, userName, sizeof(userName), 0); printf("\n\n"); _beginthreadex(NULL, 0, ThreadRecv, &ClientSocket, 0, NULL); //啟動接收和發(fā)送消息線程 _beginthreadex(NULL, 0, ThreadSend, &ClientSocket, 0, NULL); for (int k = 0;k < 1000;k++) Sleep(10000000); closesocket(ClientSocket); WSACleanup(); return 0; } int main() { ConnectServer(); //連接服務(wù)器 return 0; }
這程序還有一些BUG,其中最大的就是關(guān)掉一個連接后CPU使用率瘋漲,我測試過我想到的可能,還是找不到結(jié)果~,希望有大神懂的告知一下。
下篇請點擊socket多人聊天程序C語言版(二)
以上就是本文的全部內(nèi)容,希望對大家的學習有所幫助,也希望大家多多支持腳本之家。
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