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#include <stdlib.h>
#include <sys/types.h>
#include <string.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <libnet.h>
#define NAMELEN 28
static int
call(char *clone, char *dest, int *cfdp, char *dir, char *local)
{
int fd, cfd;
int n;
char name[3*NAMELEN+5];
char data[3*NAMELEN+10];
char *p;
cfd = open(clone, O_RDWR);
if(cfd < 0)
return -1;
/* get directory name */
n = read(cfd, name, sizeof(name)-1);
if(n < 0){
close(cfd);
return -1;
}
name[n] = 0;
p = strrchr(clone, '/');
*p = 0;
if(dir)
sprintf(dir, "%.*s/%.*s", 2*NAMELEN+1, clone, NAMELEN, name);
sprintf(data, "%.*s/%.*s/data", 2*NAMELEN+1, clone, NAMELEN, name);
/* set local side (port number, for example) if we need to */
if(local)
sprintf(name, "connect %.*s %.*s", 2*NAMELEN, dest, NAMELEN, local);
else
sprintf(name, "connect %.*s", 2*NAMELEN, dest);
/* connect */
if(write(cfd, name, strlen(name)) < 0){
close(cfd);
return -1;
}
/* open data connection */
fd = open(data, O_RDWR);
if(fd < 0){
close(cfd);
return -1;
}
if(cfdp)
*cfdp = cfd;
else
close(cfd);
return fd;
}
int
dial(char *dest, char *local, char *dir, int *cfdp)
{
char net[128];
char netdir[128], csname[NETPATHLEN], *slp;
char clone[NAMELEN+12];
char *p;
int n;
int fd;
int rv;
/* go for a standard form net!... */
p = strchr(dest, '!');
if(p == 0){
sprintf(net, "net!%.*s", sizeof(net)-5, dest);
} else {
strncpy(net, dest, sizeof(net)-1);
net[sizeof(net)-1] = 0;
}
slp = strrchr(net, '/');
if (slp != 0) {
*slp++ = '\0';
strcpy(netdir, net);
memmove(net, slp, strlen(slp)+1);
} else
strcpy(netdir, "/net");
/* call the connection server */
sprintf(csname, "%s/cs", netdir);
fd = open(csname, O_RDWR);
if(fd < 0){
/* no connection server, don't translate */
p = strchr(net, '!');
*p++ = 0;
sprintf(clone, "%s/%s/clone", netdir, net);
return call(clone, p, cfdp, dir, local);
}
/*
* send dest to connection to translate
*/
if(write(fd, net, strlen(net)) < 0){
close(fd);
return -1;
}
/*
* loop through each address from the connection server till
* we get one that works.
*/
rv = -1;
lseek(fd, 0, 0);
while((n = read(fd, net, sizeof(net) - 1)) > 0){
net[n] = 0;
p = strchr(net, ' ');
if(p == 0)
continue;
*p++ = 0;
rv = call(net, p, cfdp, dir, local);
if(rv >= 0)
break;
}
close(fd);
return rv;
}
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