linux网络编程笔记——UDP
目前这部分代码会出现阻塞问题,暂时尚未解决
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#include "udp.h" #include <stdio.h> #include <string.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <malloc.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <time.h> #include <arpa/inet.h> int PrintDiff(diff_t *diff) { printf("\n\n-----------------------\n"); printf("tow : %f\n", diff->tow); printf("numBds: %d\n", diff->numBds); printf("numGps: %d\n", diff->numGps); printf("numGln: %d\n", diff->numGln); int j; printf("system: "); for (j = 0; j < MAXSAT; ++j) { printf("%d ", diff->system[j]); } printf("\n"); printf("PRN: "); for (j = 0; j < MAXSAT; ++j) { printf("%d ", diff->PRN[j]); } printf("\n"); printf("dDO: "); for (j = 0; j < MAXSAT; ++j) { printf("%f ", diff->dDO[j]); } printf("\n"); printf("dPR: "); for (j = 0; j < MAXSAT; ++j) { printf("%f ", diff->dPR[j]); } printf("\n"); printf("------------------------------------\n"); } int server_len; int client_len; #define RECV_LOOP_COUNT 10 int recv_within_time(int fd, char *buf, size_t buf_n,struct sockaddr* addr,socklen_t *len,unsigned int sec,unsigned usec) { struct timeval tv; fd_set readfds; int i=0; unsigned int n=0; for(i=0;i<RECV_LOOP_COUNT;i++) { FD_ZERO(&readfds); FD_SET(fd,&readfds); tv.tv_sec=sec; tv.tv_usec=usec; select(fd+1,&readfds,NULL,NULL,&tv); if(FD_ISSET(fd,&readfds)) { if((n=recvfrom(fd,buf,buf_n,0,addr,len))>=0) { return n; } } } return -1; } int rover_sock_fd;/*套接字文件描述符*/ struct sockaddr_in addr_rover_server; int UdpRoverInit(char *server_ip) { char SERVER_IP_ADDRESS[20]="127.0.0.1"; strcpy(SERVER_IP_ADDRESS, server_ip); rover_sock_fd = socket(AF_INET,SOCK_DGRAM,0);//创建套接子 //初始化服务器端地址 memset(&addr_rover_server,0,sizeof(addr_rover_server)); addr_rover_server.sin_family = AF_INET; addr_rover_server.sin_addr.s_addr = inet_addr(SERVER_IP_ADDRESS); addr_rover_server.sin_port = htons(SERVER_PORT); server_len = sizeof(struct sockaddr_in); //printf("begin:\n"); return rover_sock_fd; } int UdpRoverRecieve(diff_t *diff) { int recv_num, i=0; unsigned char recv_buf[MAX_LEN_ONCE]; unsigned char send_buf[MAX_LEN_ONCE]; unsigned char *_dest=malloc(sizeof(diff_t)+MAX_LEN_ONCE); memset((void *)_dest,0,sizeof(diff_t)+MAX_LEN_ONCE); //发送命令 memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nrover_get\n"); //do sendto(rover_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_rover_server,server_len); usleep(5); while(1) { recv_num = recv_within_time(rover_sock_fd,recv_buf,MAX_LEN_ONCE,(struct sockaddr *)&addr_rover_server,&server_len,0,1000); if (recv_num<MAX_LEN_ONCE) { continue; } if(strncmp(recv_buf,"\nserver_start\n",strlen("\nserver_start\n"))) { putchar(recv_buf); printf("@@%d\n", recv_num); //return 1; } else{ printf("good\n"); break;} } while(1) { recv_within_time(rover_sock_fd,recv_buf,MAX_LEN_ONCE,(struct sockaddr *)&addr_rover_server,&server_len,0,1000); if (!strncmp(recv_buf,"\nserver_end\n",strlen("\nserver_end\n"))) break; if (!strncmp("\nserver |",recv_buf,strlen("\nserver |"))) { memcpy(_dest+i*(MAX_LEN_ONCE/2),recv_buf+(MAX_LEN_ONCE/2),MAX_LEN_ONCE/2); ++i; } printf("."); } printf("-------------%d------------\n", i); if (i!=sizeof(diff_t)/(MAX_LEN_ONCE/2)+1) { printf("%d ,get wrong, will not update this time!\n", i); } else{ memcpy((void *)diff, _dest, sizeof(diff_t)+MAX_LEN_ONCE); if (1) { PrintDiff(diff); } } free(_dest); UdpClose(rover_sock_fd); return 0; } int station_sock_fd; struct sockaddr_in addr_station_server; int UdpStationInit(char *server_ip) { char SERVER_IP_ADDRESS[20]="127.0.0.1"; strcpy(SERVER_IP_ADDRESS, server_ip); station_sock_fd = socket(AF_INET,SOCK_DGRAM,0);//创建套接子 //初始化服务器端地址 memset(&addr_station_server,0,sizeof(addr_station_server)); addr_station_server.sin_family = AF_INET; addr_station_server.sin_addr.s_addr = inet_addr(SERVER_IP_ADDRESS); addr_station_server.sin_port = htons(SERVER_PORT); server_len = sizeof(struct sockaddr_in); printf("begin send:\n"); return 0; } int UdpStationSend(diff_t *diff) { int i=0; int send_num; unsigned char send_buf[MAX_LEN_ONCE]; unsigned char *src = (unsigned char *)diff; memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nstation_start\n"); sendto(station_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_station_server,server_len); int j; for (j = 0; j < MAX_LEN_ONCE; ++j) { putchar(send_buf[j]); } for(i=0;i<sizeof(diff_t)/16+1;++i) { memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nstation|"); memcpy(send_buf+16,src+i*(MAX_LEN_ONCE/2),MAX_LEN_ONCE/2); for (j = 0; j < MAX_LEN_ONCE; ++j) { putchar(send_buf[j]); } send_num = sendto(station_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_station_server,server_len); usleep(10); } printf("---%d----%d----%d----%d----\n", i,sizeof(diff_t),MAX_LEN_ONCE/2,sizeof(diff_t)/(MAX_LEN_ONCE/2)); memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nstation_end\n"); sendto(station_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_station_server,server_len); for (j = 0; j < MAX_LEN_ONCE; ++j) { putchar(send_buf[j]); } return 0; } int server_sock_fd; //套接子描述符号 struct sockaddr_in addr_server, addr_server_client; int UdpServerInit() { int recv_num; int send_num; char recv_buf[MAX_LEN_ONCE]; server_sock_fd = socket(AF_INET,SOCK_DGRAM,0); if(server_sock_fd < 0){ perror("client socket"); exit(1); } else{ printf("client sock sucessful\n"); } memset(&addr_server,0,sizeof(struct sockaddr_in)); addr_server.sin_family = AF_INET;//协议族 addr_server.sin_port = htons(SERVER_PORT); addr_server.sin_addr.s_addr = htonl(INADDR_ANY);//任意本地址 client_len = sizeof(struct sockaddr_in); /*绑定套接字*/ if(bind(server_sock_fd,(struct sockaddr *)&addr_server,sizeof(struct sockaddr_in))<0 ){ perror("server bind"); return -1; } else{ printf("server bind sucess\n"); } return 0; } int UdpServerLoop(diff_t *diff, int arg) { int recv_num,send_num, i=0; unsigned char recv_buf[MAX_LEN_ONCE]; unsigned char send_buf[MAX_LEN_ONCE]; unsigned char *dest=malloc(sizeof(diff_t)+MAX_LEN_ONCE); memset((void *)dest,0,sizeof(diff_t)+MAX_LEN_ONCE); unsigned char *src = (unsigned char *)diff; while(1) { //update diff data recv_num = recvfrom(server_sock_fd,recv_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_server_client,&client_len); int j; if(recv_num <0 ) { perror("recv_from"); return -1; } //update diff data if (!strncmp(recv_buf,"\nstation_start\n",strlen("\nstation_start\n"))) { i=0; while(1) { recv_num = recvfrom(server_sock_fd,recv_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_server_client,&client_len); if(recv_num <0 ) { perror("recv_from"); return -1; } if (!strncmp(recv_buf,"\nstation_end\n",strlen("\nstation_end\n"))) break; if (!strncmp("\nstation|",recv_buf,strlen("\nstation|"))) { memcpy(dest+i*(MAX_LEN_ONCE/2),recv_buf+(MAX_LEN_ONCE/2),MAX_LEN_ONCE/2); ++i; } //printf("recv sucessful\n"); } printf("-------------%d------------\n", i); if (i!=sizeof(diff_t)/(MAX_LEN_ONCE/2)+1) { printf("get wrong, will not update this time!\n"); } else{ memcpy((void *)diff, dest, sizeof(diff_t)+MAX_LEN_ONCE); if (arg) { PrintDiff(diff); } } } //send diff data if(!strncmp(recv_buf,"\nrover_get\n",strlen("\nrover_get\n"))) { memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nserver_start\n"); sendto(server_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_server_client,client_len); //以后要防溢出s for(i=0;i<sizeof(diff_t)/(MAX_LEN_ONCE/2)+1;++i) { strcpy(send_buf,"\nserver |"); memcpy(send_buf+(MAX_LEN_ONCE/2),src+i*(MAX_LEN_ONCE/2),MAX_LEN_ONCE/2); send_num = sendto(server_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_server_client,client_len); if(send_num < 0){ perror("sendto"); return -1; } } memset(send_buf,0,MAX_LEN_ONCE); strcpy(send_buf,"\nserver_end\n"); sendto(server_sock_fd,send_buf,MAX_LEN_ONCE,0,(struct sockaddr *)&addr_server_client,client_len); } } return 0; } int UdpClose(int sock_fd) { close(sock_fd); return 0; }
作者:catmelo
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