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#include "bbs.h"
#include <err.h>
void usage(void);
int connectserver(char *, int);
void listennetwork(int, int);
void listenmsgqueue(int, int);
int main(int argc, char **argv)
{
char *host = NULL;
int port = 0, ch, sfd, msto, mtos;
pid_t pid;
while( (ch = getopt(argc, argv, "s:p:")) != -1 )
switch( ch ){
case 's':
host = strdup(optarg);
break;
case 'p':
port = atoi(optarg);
break;
default:
usage();
}
if( host == NULL || port == 0 )
usage();
printf("connecting to server %s:%d\n", host, port);
sfd = connectserver(host, port);
puts("connected");
puts("attaching message queue");
if( (msto = msgget(OC_msto, 0600 | IPC_CREAT)) < 0 )
err(1, "msgget OC_msto");
if( (mtos = msgget(OC_mtos, 0600 | IPC_CREAT)) < 0 )
err(1, "msgget OC_mtos");
puts("attached");
if( (pid = fork()) < 0 )
err(1, "fork()");
else if( pid == 0 )
listennetwork(sfd, msto);
listenmsgqueue(sfd, mtos);
return 0;
}
void usage(void)
{
fprintf(stderr, "usage:\tlocalserver -s host -p port\n");
exit(0);
}
int connectserver(char *host, int port)
{
struct sockaddr_in servaddr;
int fd;
if( (fd = socket(AF_INET, SOCK_STREAM, 0)) < 0 )
err(1, "socket");
bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;
inet_pton(AF_INET, host, &servaddr.sin_addr);
servaddr.sin_port = htons(port);
if( connect(fd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0 )
err(1, "connect");
return fd;
}
void listennetwork(int netfd, int msgfd)
{
int len;
char buf[CACHE_BUFSIZE];
printf("(%d)listening network %d => message queue %d\n",
getpid(), netfd, msgfd);
while( Read(netfd, &len, 4) > 0 ){
if( Read(netfd, buf, len) < 0 )
err(1, "(network)read()");
if( msgsnd(msgfd, buf, len, 0) < 0 )
err(1, "(network)msgsnd()");
}
exit(0);
}
void listenmsgqueue(int netfd, int msgfd)
{
char buf[CACHE_BUFSIZE];
OCbuf_t *ptr;
int len;
printf("(%d)listening message queue %d => network %d\n",
getpid(), msgfd, netfd);
while( msgrcv(msgfd, buf, CACHE_BUFSIZE, 0, 0) > 0 ){
ptr = (OCbuf_t *)buf;
len = ptr->length + OC_HEADERLEN;
if( write(netfd, &len, sizeof(len)) < 0 ||
write(netfd, ptr, ptr->length + OC_HEADERLEN) < 0 )
err(1, "(msgqueue)write()");
}
err(1, "(msgqueue)msgrcv()");
exit(0);
}
ssize_t Read(int fd, void *BUF, size_t nbytes)
{
char *buf = (char *)BUF;
size_t thisgot, totalgot = nbytes;
while( nbytes > 0 ){
if( (thisgot = read(fd, buf, nbytes)) <= 0 )
err(1, "read from socket: ");
nbytes -= thisgot;
buf += thisgot;
}
return totalgot;
}
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