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/*
* $smu-mark$
* $name: resolve.c$
* $author: Salvatore Sanfilippo <antirez@invece.org>$
* $copyright: Copyright (C) 1999 by Salvatore Sanfilippo$
* $license: This software is under GPL version 2 of license$
* $date: Fri Nov 5 11:55:49 MET 1999$
* $rev: 8$
*/
/* $Id: resolve.c,v 1.2 2003/09/01 00:22:06 antirez Exp $ */
#include <stdlib.h>
#include <sys/types.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
/* On error -1 is returned, on success 0 */
int resolve_addr(struct sockaddr * addr, char *hostname)
{
struct sockaddr_in *address;
struct hostent *host;
address = (struct sockaddr_in *)addr;
memset(address, 0, sizeof(struct sockaddr_in));
address->sin_family = AF_INET;
address->sin_addr.s_addr = inet_addr(hostname);
if ( (int)address->sin_addr.s_addr == -1) {
host = gethostbyname(hostname);
if (host) {
memcpy(&address->sin_addr, host->h_addr,
host->h_length);
return 0;
} else {
return -1;
}
}
return 0;
}
/* Like resolve_addr but exit on error */
void resolve(struct sockaddr *addr, char *hostname)
{
if (resolve_addr(addr, hostname) == -1) {
fprintf(stderr, "Unable to resolve '%s'\n", hostname);
exit(1);
}
}
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