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/* posix */
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
/* socket extensions */
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/un.h>
#include <netdb.h>
#include "priv.h"
static char pbotch[] = "rcmd: protocol botch\n";
static char lbotch[] = "rcmd: botch starting error stream\n";
static void
ding(int x)
{
}
int
rcmd(char **dst, int port, char *luser, char *ruser, char *cmd, int *fd2p)
{
char c;
int i, fd, lfd, fd2, port2;
struct hostent *h;
Rock *r;
struct sockaddr_in in;
char buf[128];
void (*x)(int);
h = gethostbyname(*dst);
if(h == 0)
return -1;
*dst = h->h_name;
/* connect using a reserved tcp port */
fd = socket(PF_INET, SOCK_STREAM, 0);
if(fd < 0)
return -1;
r = _sock_findrock(fd, 0);
if(r == 0){
errno = ENOTSOCK;
return -1;
}
r->reserved = 1;
in.sin_family = AF_INET;
in.sin_port = htons(port);
memmove(&in.sin_addr, h->h_addr_list[0], sizeof(in.sin_addr));
if(connect(fd, &in, sizeof(in)) < 0){
close(fd);
return -1;
}
/* error stream */
if(fd2p){
/* create an error stream and wait for a call in */
for(i = 0; i < 10; i++){
lfd = rresvport(&port2);
if(lfd < 0)
continue;
if(listen(lfd, 1) == 0)
break;
close(lfd);
}
if(i >= 10){
fprintf(stderr, pbotch);
return -1;
}
snprintf(buf, sizeof buf, "%d", port2);
if(write(fd, buf, strlen(buf)+1) < 0){
close(fd);
close(lfd);
fprintf(stderr, lbotch);
return -1;
}
} else {
if(write(fd, "", 1) < 0){
fprintf(stderr, pbotch);
return -1;
}
}
/* pass id's and command */
if(write(fd, luser, strlen(luser)+1) < 0
|| write(fd, ruser, strlen(ruser)+1) < 0
|| write(fd, cmd, strlen(cmd)+1) < 0){
if(fd2p)
close(fd2);
fprintf(stderr, pbotch);
return -1;
}
if(fd2p){
x = signal(SIGALRM, ding);
alarm(15);
fd2 = accept(lfd, &in, &i);
alarm(0);
close(lfd);
signal(SIGALRM, x);
if(fd2 < 0){
close(fd);
close(lfd);
fprintf(stderr, lbotch);
return -1;
}
*fd2p = fd2;
}
/* get reply */
if(read(fd, &c, 1) != 1){
if(fd2p)
close(fd2);
fprintf(stderr, pbotch);
return -1;
}
if(c == 0)
return fd;
i = 0;
while(c){
buf[i++] = c;
if(read(fd, &c, 1) != 1)
break;
if(i >= sizeof(buf)-1)
break;
}
buf[i] = 0;
fprintf(stderr, "rcmd: %s\n", buf);
close(fd);
return -1;
}
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