C语言实现linux环境UDP协议接收发送数据
说明上代码运行结果说明
闲来无事，写了个C语言的UDP小程序，程序新建了两个线程，分别用来实现UDP数据到发送和接收。需要的直接拿去用。
上代码
#include <stdio.h>#include <pthread.h>#include <unistd.h>#include <netinet/in.h>#include <string.h>#include <arpa/inet.h>#include <stdbool.h>#define MAX_UDP_RCV_LEN 512#define LS_OK 0#define LS_ERR -1#define TRUE1#define FALSE 0typedef struct UDP_UNICAST_ST{int sockfd;struct sockaddr_in PeerAddr;char RcvBuf[MAX_UDP_RCV_LEN];}UdpUnicastSt;static pthread_t keepAliveThreadId;static UdpUnicastSt g_udpUnicast;static pthread_t NetWorkUdpUnicastThreadId1;static pthread_t NetWorkUdpUnicastThreadId2;/***************************************************************************function: setThreadAttrinput:output:Description:****************************************************************************/void setThreadAttr(pthread_attr_t *thread_attr, unsigned int priority, size_t stack_size){size_t StackSize = 0;pthread_attr_init(thread_attr);//首先需要对属性变量进行初始化pthread_attr_setscope(thread_attr, PTHREAD_SCOPE_PROCESS);pthread_attr_setdetachstate(thread_attr, PTHREAD_CREATE_JOINABLE);struct sched_param param;pthread_attr_getschedparam(thread_attr, ¶m);param.sched_priority = (int)priority;pthread_attr_setschedparam(thread_attr, ¶m);if(stack_size < 0x4000) //以字节为单位 最小16k{StackSize = 0x4000;}pthread_attr_setstacksize(thread_attr, StackSize);}void *keepAliveProcess(){while(1){printf("udp process is alive!\n");sleep(180);}}/***************************************************************************function: createThreadinput:output:Description:提供统一线程创建函数****************************************************************************/int createThread(pthread_t *thread_id, const pthread_attr_t *attr, void *(*thread_fun) (void *), void *thread_arg){int ret = -1;ret = pthread_create(thread_id, attr, thread_fun, thread_arg);return ret;}/***************************************************************************function: keepAliveThreadinput:output:Description:****************************************************************************/static int keepAliveThread(void){int ret = -1;pthread_attr_t Thread_Attr;setThreadAttr(&Thread_Attr, 11, 0x8000);ret = createThread(&keepAliveThreadId, &Thread_Attr, keepAliveProcess, NULL);if(ret != 0){printf("keepAliveThread failed!\n");}return ret;}void threadWaitDone(void **reval){pthread_join(keepAliveThreadId, reval);}/***************************************************************************function: UdpUnicastInitinput:output:Description:udp socket初始化****************************************************************************/int UdpUnicastInit(){int ret = -1;g_udpUnicast.sockfd = socket(AF_INET,SOCK_DGRAM, 0);if (g_udpUnicast.sockfd < 0){printf("Create UDP socket failed!\n");return LS_ERR;}struct sockaddr_in LocalAddr;memset(&LocalAddr, 0, sizeof(struct sockaddr_in));LocalAddr.sin_family = AF_INET;LocalAddr.sin_port = htons(13903); //临时指定为13903,征途智能门锁有线传感器LocalAddr.sin_addr.s_addr = INADDR_ANY;ret = bind(g_udpUnicast.sockfd, (struct sockaddr *)(&LocalAddr), sizeof(struct sockaddr));if (-1 == ret){close(g_udpUnicast.sockfd);g_udpUnicast.sockfd = -1;return LS_ERR;}return LS_OK;}/***************************************************************************function: modbusMsgPrintinput:output:Description:打印串口数据****************************************************************************/void modbusMsgPrint(unsigned char *pBuffer, int buffLen, bool bRcvFlag){if(NULL == pBuffer || 0 == buffLen){return;}char szPrint[4096] = {0};int i = 0;for(i = 0;i < buffLen; i++){snprintf(&(szPrint[strlen(szPrint)]),4096 - strlen(szPrint)," 0x%02X",pBuffer[i]);}if(bRcvFlag){printf("Rcv:%s.\n",szPrint);}else{printf("Send:%s.\n",szPrint);}}/***************************************************************************function: NetWorkUdpUnicastSendThreadinput:output:Description:udp数据发送线程****************************************************************************/void* NetWorkUdpUnicastSendThread(void *param){socklen_taddrLen= 0;unsigned char sendBuff[64] = {1,1,2,2,3,3,4,4,5};int recvRet= 0;struct sockaddr_in LocalAddr;addrLen = sizeof(struct sockaddr);memset(&LocalAddr, 0, sizeof(struct sockaddr_in));LocalAddr.sin_family = AF_INET;LocalAddr.sin_port = htons(13903); //临时指定为13903printf("start NetWorkUdpUnicastSendThread....!\n");while(1){LocalAddr.sin_addr.s_addr = inet_addr("192.168.8.28");//临时指定为192.168.90.56recvRet = (int)sendto(g_udpUnicast.sockfd, sendBuff, 11, 0, (struct sockaddr*)&LocalAddr, addrLen);printf("UDP send %d data: %s\n", recvRet, sendBuff);modbusMsgPrint(sendBuff, recvRet, FALSE);sleep(60);}}/***************************************************************************function: NetWorkUdpUnicastRecvThreadinput:output:Description:udp数据接收线程****************************************************************************/void* NetWorkUdpUnicastRecvThread(void *param){int recvRet= -1;socklen_taddrLen= 0;addrLen = sizeof(struct sockaddr);printf("start NetWorkUdpUnicastRecvThread....!\n");while(1){recvRet = (int)recvfrom(g_udpUnicast.sockfd, g_udpUnicast.RcvBuf, MAX_UDP_RCV_LEN - 1,0,(struct sockaddr*)(&g_udpUnicast.PeerAddr),&addrLen);if (-1 == recvRet){printf("UDP recv data failed!\n");continue;}printf("UDP recv %d data: %s\n", recvRet, g_udpUnicast.RcvBuf);modbusMsgPrint((unsigned char *)g_udpUnicast.RcvBuf, recvRet, TRUE);}}/***************************************************************************function: NetWorkUdpUnicastInitinput:output:Description:udp客户端创建初始化****************************************************************************/int netWorkUdpUnicastInit(){int ret = -1;pthread_attr_t Thread_Attr1;pthread_attr_t Thread_Attr2;memset(&g_udpUnicast, 0,sizeof(UdpUnicastSt));ret = UdpUnicastInit();if(LS_OK != ret){printf("UDP Socket init failed!\n");return LS_ERR;}setThreadAttr(&Thread_Attr1,20,0x8000);ret = createThread(&NetWorkUdpUnicastThreadId1, &Thread_Attr1, NetWorkUdpUnicastSendThread, NULL);if(ret != 0){printf("Create network udp send thread failed!\n");return LS_ERR;}setThreadAttr(&Thread_Attr2,20,0x8000);ret = createThread(&NetWorkUdpUnicastThreadId2, &Thread_Attr2, NetWorkUdpUnicastRecvThread, NULL);if(ret != 0){printf("Create network udp recv thread failed!\n");return LS_ERR;}return LS_OK;}int main(){printf("---udp process start---\n");void *thread_reval = NULL;//udpnetWorkUdpUnicastInit();//进程保活keepAliveThread();threadWaitDone(&thread_reval);if(thread_reval != NULL){printf("thread_reval : %s is not null\n", (char *)thread_reval);}//不会运行至此printf("---udp process end---\n");return 0;}
运行结果
linux环境下运行进程或者直接QT编译运行，这里的结果展示为centos虚拟机的QT运行。
虚拟机ip为192.168.8.235，程序里UDP的端口写死的13903。
宿主机的ip为192.168.8.28，运行一个UDP的模拟工具。
本程序定时发送一串字节流，模拟工具可以正常接收。
模拟工具发送字节流，程序也可以正常接收显示。
打完收工。
