このコードを実行すると、「Hello」と入力するとすぐに別れが表示されず、エラーとして「非ソケットでのソケット操作」で終了します。また、クライアントからメッセージを送信すると (localhost ubuntu/複数のコンソールを使用) .I 2 番目のコンソール (クライアント) 以降からのメッセージのみを表示できますが、最初のコンソールからは表示されません。最初のクライアントの場合は、メッセージが表示された後に接続が終了します。
Cのサーバーコード
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#define PORT "3490"
#define STDIN 0
#define STDOUT 1
char *opt;
void *get_in_addr(struct sockaddr *sa)
{
if (sa->sa_family == AF_INET) {
return &(((struct sockaddr_in*)sa)->sin_addr);
}
return &(((struct sockaddr_in6*)sa)->sin6_addr);
}
int main(void)
{
fd_set master;
fd_set read_fds;
int fdmax;
// master file descriptor list
// temp file descriptor list for select()
// maximum file descriptor number
int listener;
// listening socket descriptor
int newfd;
// newly accept()ed socket descriptor
struct sockaddr_storage remoteaddr; // client address
socklen_t addrlen;
char buf[256];
int nbytes;
// buffer for client data
char remoteIP[INET6_ADDRSTRLEN];
int yes=1;
int i, j, rv;
// for setsockopt() SO_REUSEADDR, below
struct addrinfo hints, *ai, *p;
FD_ZERO(&master);
FD_ZERO(&read_fds);
// clear the master and temp sets
// get us a socket and bind it
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_PASSIVE;
if ((rv = getaddrinfo(NULL, PORT, &hints, &ai)) != 0) {
fprintf(stderr, "selectserver: %s\n", gai_strerror(rv));
exit(1);
}
for(p = ai; p != NULL; p = p->ai_next) {
listener = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
if (listener < 0) {
continue;
}
// lose the pesky "address already in use" error message
setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int));
if (bind(listener, p->ai_addr, p->ai_addrlen) < 0) {
close(listener);
continue;
}
break;
}
// if we got here, it means we didn't get bound
if (p == NULL) {
fprintf(stderr, "selectserver: failed to bind\n");
exit(2);
}
freeaddrinfo(ai); // all done with this
// listen
if (listen(listener, 10) == -1) {
perror("listen");
exit(3);
}
// add the listener to the master set
FD_SET(listener, &master);
FD_SET(STDIN,&master);
// keep track of the biggest file descriptor
fdmax = listener; // so far, it's this one
// main loop
for(;;) {
read_fds = master; // copy it
if (select(fdmax+1, &read_fds, NULL, NULL, NULL) == -1) {
perror("select");
exit(4);
}
// run through the existing connections looking for data to read
for(i = 0; i <= fdmax; i++) {
if (FD_ISSET(i, &read_fds)) { // we got one!!
if (i == listener) {
// handle new connections
addrlen = sizeof remoteaddr;
newfd = accept(listener,
(struct sockaddr *)&remoteaddr,
&addrlen);
if (newfd == -1) {
perror("accept");
} else {
FD_SET(newfd, &master); // add to master set
if (newfd > fdmax) {
// keep track of the max
fdmax = newfd;
}
printf("selectserver: new connection from %s on "
"socket %d\n",inet_ntop(remoteaddr.ss_family,
get_in_addr((struct sockaddr*)&remoteaddr),
remoteIP, INET6_ADDRSTRLEN),
newfd);
}
} else {
// handle data from a client
if ((nbytes = recv(i, buf, sizeof buf, 0)) <= 0) {
// got error or connection closed by client
if (nbytes == 0) {
// connection closed
printf("selectserver: socket %d hung up\n", i);
} else {
perror("recv");
}
close(i); // bye!
FD_CLR(i, &master); // remove from master set
} else {
if(i==STDIN){
printf("Goodbye");
}
// we got some data from a client
for(j = 0; j <= fdmax; j++) {
// send to everyone!
if (FD_ISSET(j, &master)) {
// except the listener and ourselves
if (j != listener && j != i) {
if (send(j, buf, nbytes, 0) == -1) {
perror("send");
}
}
}
}
}
} // END handle data from client
} // END got new incoming connection
} // END looping through file descriptors
} // END for(;;)--and you thought it would never end!
return 0;
}
//新しいコードが変更されました。読み取りによって stdin データが取得されると、おそらくブロッキングが原因で他の接続に応答しません助けてください
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/time.h>
#define TRUE 1
#define FALSE 0
//Var
int mode,info;
int PORT;
char *ip_host;
int i,len,rc,on=1;
int listen_sd,max_sd,new_sd;
int desc_ready,end_server=FALSE;
int close_conn;
char buffer[256];
//struct sockaddr_in addr;
struct timeval timeout;
fd_set master_set,working_set;
struct sockaddr_storage remoteaddr; // client addres//s
socklen_t addrlen;
char remoteIP[INET6_ADDRSTRLEN];
char s[INET6_ADDRSTRLEN];
struct addrinfo hints, *loadinfo, *ptr;
void *get_in_addr(struct sockaddr *sa)
{
if (sa->sa_family == AF_INET) {
return &(((struct sockaddr_in*)sa)->sin_addr);
}
return &(((struct sockaddr_in6*)sa)->sin6_addr);
}
void servcl_memset(){
memset(&hints, 0, sizeof(hints));
hints.ai_family= AF_UNSPEC;
hints.ai_socktype= SOCK_STREAM;
}
void cl_connect()
{
for(ptr = loadinfo; ptr != NULL; ptr = ptr->ai_next) {
if ((listen_sd = socket(ptr->ai_family, ptr->ai_socktype,ptr->ai_protocol)) == -1) {
perror("client: socket");
continue;
}
if (connect(listen_sd, ptr->ai_addr, ptr->ai_addrlen) == -1) {
close(listen_sd);
perror("client: connect");
continue;
}
break;
}
if (ptr == NULL) {
fprintf(stderr, "client: failed to connect(bind)\n");
exit(0);
}
inet_ntop(ptr->ai_family, get_in_addr((struct sockaddr *)ptr->ai_addr),s, sizeof s);
printf("client: connecting to %s\n", s);
freeaddrinfo(loadinfo); // all done with this structure
}
void init_socket(){
for(ptr = loadinfo; ptr != NULL; ptr = ptr->ai_next) {
if ((listen_sd = socket(ptr->ai_family, ptr->ai_socktype,ptr->ai_protocol)) == -1) {
perror("server: socket");
continue;
}
rc = setsockopt(listen_sd, SOL_SOCKET, SO_REUSEADDR,(char *)&on, sizeof(on));
if (rc < 0)
{
perror("setsockopt() failed");
close(listen_sd);
continue;
}
rc = bind(listen_sd,ptr->ai_addr,ptr->ai_addrlen);
if (rc < 0)
{
perror("bind() failed");
close(listen_sd);
continue;
}
break;
}//End For
if (ptr == NULL) {
fprintf(stderr, "client/server: failed to connect(bind)\n");
exit(0);
}
freeaddrinfo(loadinfo); // all done with this structure
}
void unblock(){
rc = ioctl(listen_sd, FIONBIO, (char *)&on);
if (rc < 0)
{
perror("ioctl() failed");
close(listen_sd);
exit(-1);
}
}
void sock_listen(){
rc = listen(listen_sd, 32);
if (rc < 0)
{
perror("listen() failed");
close(listen_sd);
exit(-1);
}
/*************************************************************/
/* Initialize the master fd_set
*/
/*************************************************************/
FD_ZERO(&master_set);
max_sd = listen_sd;
FD_SET(0,&master_set);
FD_SET(listen_sd, &master_set);
}
void conn_timeout(){
timeout.tv_sec = 3 * 60;
timeout.tv_usec = 0;
}
/*void client_listen(){
do
{
memcpy(&working_set, &master_set, sizeof(master_set));
printf("Waiting on select()...\n");
rc = select(max_sd + 1, &working_set, NULL, NULL, &timeout);
if (rc < 0)
{
perror(" select() failed");
break;
}
if (rc == 0)
{
printf(" select() timed out. End program.\n");
break;
}
desc_ready = rc;
*/
void start_listen(){
do
{
memcpy(&working_set, &master_set, sizeof(master_set));
printf("Waiting on select()...\n");
rc = select(max_sd + 1, &working_set, NULL, NULL, &timeout);
if (rc < 0)
{
perror(" select() failed");
break;
}
if (rc == 0)
{
printf(" select() timed out. End program.\n");
break;
}
desc_ready = rc;
for (i=0; i <= max_sd && desc_ready > 0; ++i)
{
if (FD_ISSET(i, &working_set))
{
desc_ready -= 1;
if (i == listen_sd)
{
printf(" Listening socket is readable\n");
do
{
addrlen = sizeof remoteaddr;
new_sd = accept(listen_sd, (struct sockaddr *)&remoteaddr,&addrlen);
if (new_sd < 0)
{
if (errno != EWOULDBLOCK)
{
perror(" accept() failed");
end_server = TRUE;
}
break;
}
printf(" New incoming connection - %d\n", new_sd);
printf("selectserver: new connection from %s on "
"socket %d\n",
inet_ntop(remoteaddr.ss_family,
get_in_addr((struct sockaddr*)&remoteaddr),
remoteIP, INET6_ADDRSTRLEN),
new_sd);
FD_SET(new_sd, &master_set);
if (new_sd > max_sd)
max_sd = new_sd;
} while (new_sd != -1);
}
else
{
printf(" Descriptor %d is readable\n", i);
close_conn = FALSE;
//do
//{
rc = read(i, buffer, sizeof(buffer)-1);
if (rc < 0)
{
if (errno != EWOULDBLOCK)
{
perror(" recv() failed");
close_conn = TRUE;
}
break;
}
if (rc == 0)
{
printf(" Connection closed\n");
close_conn = TRUE;
break;
}
len = rc;
printf(" %d bytes received\n", len);
if (i==0)i=1;
rc = write(i, buffer, len);
if (i==1)i=0;
if (rc < 0)
{
perror(" send() failed");
close_conn = TRUE;
break;
}
//} while (TRUE);
if (close_conn)
{
close(i);
FD_CLR(i, &master_set);
if (i == max_sd)
{
while (FD_ISSET(max_sd, &master_set) == FALSE)
max_sd -= 1;
}
}
} /* End of existing connection is readable */
} /* End of if (FD_ISSET(i, &working_set)) */
} /* End of loop through selectable descriptors */
end_server==TRUE;} while (end_server == FALSE);
}
void conn_close(){
for (i=0; i <= max_sd; ++i)
{
if (FD_ISSET(i, &master_set))
close(i);
}
}
void cl_socket() {
printf("Please enter the message: ");
do
{
memcpy(&working_set, &master_set, sizeof(master_set));
printf("Waiting on select()...\n");
rc = select(max_sd + 1, &working_set, NULL, NULL,NULL);
if (rc < 0)
{
perror(" select() failed");
break;
}
desc_ready = rc;
for (i=0; i <= max_sd && desc_ready > 0; ++i)
{
if (FD_ISSET(i, &working_set))
{
desc_ready -= 1;
printf(" Descriptor %d is readable\n", i);
close_conn = FALSE;
do
{
fgets(buffer,255,stdin);
rc = write(listen_sd, buffer,strlen(buffer));
if (rc < 0)
{
perror(" send() failed");
close_conn = TRUE;
}
rc = read(listen_sd, buffer, sizeof(buffer)-1);
if (rc < 0)
{
if (errno != EWOULDBLOCK)
{
perror(" recv() failed");
close_conn = TRUE;
}
}
if (rc == 0)
{
printf(" Connection closed\n");
close_conn = TRUE;
}
len = rc;
printf(" %d bytes received\n", len);
} while (TRUE);
if (close_conn)
{
close(i);
FD_CLR(i, &master_set);
if (i == max_sd)
{
while (FD_ISSET(max_sd, &master_set) == FALSE)
max_sd -= 1;
}
}
}//Working set
}//For loop
end_server==TRUE;} while (end_server == FALSE);
}
main(int argc,char * argv[])
{
mode=atoi(argv[1]);
PORT=atoi(argv[2]);
ip_host=(argv[3]);
servcl_memset();
if (mode ==1){
printf("In client mode\n");
if ((info = getaddrinfo(argv[3], argv[2], &hints, &loadinfo)) != 0) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(info));
return 1;
}
cl_connect();
unblock();
conn_timeout();
cl_socket();
conn_close();
}
else {
printf("In server mode\n");
hints.ai_flags=AI_PASSIVE;
if ((info = getaddrinfo(NULL, argv[2], &hints, &loadinfo)) != 0) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(info));
return 1;
}
init_socket();
unblock();
sock_listen();
conn_timeout();
start_listen();
conn_close();
}
}
/*
*/
テストに使用している別のクライアントもあります。
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
void error(const char *msg)
{
perror(msg);
exit(0);
}
int main(int argc, char *argv[])
{
int sockfd, portno, n;
struct sockaddr_in serv_addr;
struct hostent *server;
char buffer[256];
if (argc < 3) {
fprintf(stderr,"usage %s hostname port\n", argv[0]);
exit(0);
}
portno = atoi(argv[2]);
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
error("ERROR opening socket");
server = gethostbyname(argv[1]);
if (server == NULL) {
fprintf(stderr,"ERROR, no such host\n");
exit(0);
}
bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
bcopy((char *)server->h_addr,
(char *)&serv_addr.sin_addr.s_addr,
server->h_length);
serv_addr.sin_port = htons(portno);
if (connect(sockfd,(struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0)
error("ERROR connecting");
printf("Please enter the message: ");
bzero(buffer,256);
fgets(buffer,255,stdin);
n = write(sockfd,buffer,strlen(buffer));
if (n < 0)
error("ERROR writing to socket");
bzero(buffer,256);
n = read(sockfd,buffer,255);
if (n < 0)
error("ERROR reading from socket");
printf("%s\n",buffer);
close(sockfd);
return 0;
}