daytime/0040755001362700136270000000000007550352574010656 5ustar evaevadaytime/tcpserver.c0100640001362700136270000000331307550347245013027 0ustar evaeva#include #include #include #include #include #include #include #include "listen_server.h" const char *DAYTIME_PORT="13111"; int main(int argc, char *argv[]) { int listenfd, connfd; socklen_t addrlen; char timeStr[256]; struct sockaddr_storage clientaddr; time_t now; char clienthost[NI_MAXHOST]; char clientservice[NI_MAXSERV]; /* local server socket listening at daytime port=13 */ listenfd = listen_server(NULL, DAYTIME_PORT, AF_UNSPEC, SOCK_STREAM); if (listenfd < 0) { fprintf(stderr, "listen_socket error:: could not create listening " "socket\n"); return -1; } for ( ; ;) { addrlen = sizeof(clientaddr); /* accept daytime client connections */ connfd = accept(listenfd, (struct sockaddr *)&clientaddr, &addrlen); if (connfd < 0) continue; memset(clienthost, 0, sizeof(clienthost)); memset(clientservice, 0, sizeof(clientservice)); getnameinfo((struct sockaddr *)&clientaddr, addrlen, clienthost, sizeof(clienthost), clientservice, sizeof(clientservice), NI_NUMERICHOST); printf("Received request from host=[%s] port=[%s]\n", clienthost, clientservice); /* process daytime request from a client */ memset(timeStr, 0, sizeof(timeStr)); time(&now); sprintf(timeStr, "%s", ctime(&now)); write(connfd, timeStr, strlen(timeStr)); close(connfd); } return 0; } daytime/tcpclient.c0100640001362700136270000000140607550347257013003 0ustar evaeva#include #include #include #include #include #include #include "connect_client.h" const char *DAYTIME_PORT="13111"; int main(int argc, char *argv[]) { int connfd; char *myhost; char timeStr[256]; myhost = "localhost"; if (argc > 1) myhost = argv[1]; connfd = connect_client(myhost, DAYTIME_PORT, AF_UNSPEC, SOCK_STREAM); if (connfd < 0) { fprintf(stderr, "client error:: could not create connected socket " "socket\n"); return -1; } memset(timeStr, 0, sizeof(timeStr)); while (read(connfd, timeStr, sizeof(timeStr)) > 0) printf("%s", timeStr); close(connfd); return 0; } daytime/udpserver.c0100640001362700136270000000333707550347222013032 0ustar evaeva#include #include #include #include #include #include #include "listen_server.h" const char *DAYTIME_PORT="13111"; int main(int argc, char *argv[]) { int listenfd, n; socklen_t addrlen; char *myhost; char timeStr[256]; struct sockaddr_storage clientaddr; time_t now; char b[256]; char clienthost[NI_MAXHOST]; char clientservice[NI_MAXSERV]; myhost="localhost"; if (argc > 1) myhost=argv[1]; listenfd = listen_server(myhost, DAYTIME_PORT, AF_UNSPEC, SOCK_DGRAM); if (listenfd < 0) { fprintf(stderr, "listen_server error:: could not create listening " "socket\n"); return -1; } addrlen = sizeof(clientaddr); for ( ; ;) { n = recvfrom(listenfd, b, sizeof(b), 0, (struct sockaddr *)&clientaddr, &addrlen); if (n < 0) continue; memset(clienthost, 0, sizeof(clienthost)); memset(clientservice, 0, sizeof(clientservice)); getnameinfo((struct sockaddr *)&clientaddr, addrlen, clienthost, sizeof(clienthost), clientservice, sizeof(clientservice), NI_NUMERICHOST); printf("Received request from host=[%s] port=[%s]\n", clienthost, clientservice); memset(timeStr, 0, sizeof(timeStr)); time(&now); sprintf(timeStr, "%s", ctime(&now)); n = sendto(listenfd, timeStr, sizeof(timeStr), 0, (struct sockaddr *)&clientaddr, addrlen); } return 0; } daytime/udpclient.c0100644001362700136270000000156207550347233013006 0ustar evaeva#include #include #include #include #include #include #include "connect_client.h" const char *DAYTIME_PORT="13111"; int main(int argc, char *argv[]) { int connfd, n, m; char *myhost; char timeStr[256]; char letter; myhost = "localhost"; if (argc > 1) myhost=argv[1]; connfd = connect_client(myhost, DAYTIME_PORT, AF_UNSPEC, SOCK_DGRAM); if (connfd < 0) { fprintf(stderr, "client error:: could not create connected socket " "socket\n"); return -1; } letter = '1'; m= write(connfd, &letter, sizeof(letter)); memset(timeStr, 0, sizeof(timeStr)); n = read(connfd, timeStr, sizeof(timeStr)); printf("%s\n", timeStr); close(connfd); return 0; } daytime/Makefile0100644001362700136270000000050007550344333012300 0ustar evaeva CXX=gcc CXXFLAGS=-pedantic -Wall LD=$(CXX) LDFLAGS=$(CXXFLAGS) all: tcpserver udpserver tcpclient udpclient tcpserver: listen_server.o udpserver: listen_server.o tcpclient: connect_client.o udpclient: connect_client.o listen_server.o: connect_client.o: clean: rm -f *.o tcpserver udpserver tcpclient udpclient daytime/listen_server.c0100640001362700136270000000354507550344255013703 0ustar evaeva#include #include #include #include #include "listen_server.h" const int LISTEN_QUEUE=128; int listen_server(const char *hostname, const char *service, int family, int socktype) { struct addrinfo hints, *res, *ressave; int n, sockfd; memset(&hints, 0, sizeof(struct addrinfo)); /* AI_PASSIVE flag: we use the resulting address to bind to a socket for accepting incoming connections. So, when the hostname==NULL, getaddrinfo function will return one entry per allowed protocol family containing the unspecified address for that family. */ hints.ai_flags = AI_PASSIVE; hints.ai_family = family; hints.ai_socktype = socktype; n = getaddrinfo(hostname, service, &hints, &res); if (n <0) { fprintf(stderr, "getaddrinfo error:: [%s]\n", gai_strerror(n)); return -1; } ressave=res; /* Try open socket with each address getaddrinfo returned, until we get a valid listening socket. */ sockfd=-1; while (res) { sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (!(sockfd < 0)) { if (bind(sockfd, res->ai_addr, res->ai_addrlen) == 0) break; close(sockfd); sockfd=-1; } res = res->ai_next; } if (sockfd < 0) { freeaddrinfo(ressave); fprintf(stderr, "socket error:: could not open socket\n"); return -1; } listen(sockfd, LISTEN_QUEUE); freeaddrinfo(ressave); return sockfd; } daytime/listen_server.h0100640001362700136270000000061307550344255013701 0ustar evaeva#ifndef listen__server__h__ #define listen__server__h__ /* listen_server creates a server server socket listening at a hostname:service using the family and socket type specified in the function arguments. */ int listen_server(const char *hostname, const char *service, int family, int socktype); #endif daytime/connect_client.h0100640001362700136270000000034007550344255014001 0ustar evaeva#ifndef connect__client__h__ #define connect__client__h__ int connect_client (const char *hostname, const char *service, int family, int socktype); #endif daytime/connect_client.c0100640001362700136270000000222207550344255013775 0ustar evaeva#include #include #include #include #include "connect_client.h" int connect_client (const char *hostname, const char *service, int family, int socktype) { struct addrinfo hints, *res, *ressave; int n, sockfd; memset(&hints, 0, sizeof(struct addrinfo)); hints.ai_family = family; hints.ai_socktype = socktype; n = getaddrinfo(hostname, service, &hints, &res); if (n <0) { fprintf(stderr, "getaddrinfo error:: [%s]\n", gai_strerror(n)); return -1; } ressave = res; sockfd=-1; while (res) { sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (!(sockfd < 0)) { if (connect(sockfd, res->ai_addr, res->ai_addrlen) == 0) break; close(sockfd); sockfd=-1; } res=res->ai_next; } freeaddrinfo(ressave); return sockfd; } daytime/readme0100644001362700136270000000031307550352570012024 0ustar evaevaThese are TCP/UDP client/server simple applications which could be used over IPv4 and IPv6 networks. Daytime port is number 13, instead of this one we use 13111. Comments are welcome, eva@dit.upm.es.