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/*
* Copyright (C) 2022 Amazon.com, Inc. or its affiliates. All rights reserved.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*/
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef __wasi__
#include <wasi_socket_ext.h>
#else
#include <netdb.h>
#endif
int
lookup_host(const char *host)
{
struct addrinfo hints, *res, *result;
int errcode;
char addrstr[100];
void *ptr;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
errcode = getaddrinfo(host, NULL, &hints, &result);
if (errcode != 0) {
perror("getaddrinfo");
return -1;
}
res = result;
printf("Host: %s\n", host);
while (res) {
switch (res->ai_family) {
case AF_INET:
ptr = &((struct sockaddr_in *)res->ai_addr)->sin_addr;
break;
case AF_INET6:
ptr = &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr;
break;
default:
printf("Unsupported address family: %d\n", res->ai_family);
continue;
}
inet_ntop(res->ai_family, ptr, addrstr, 100);
printf("IPv%d address: %s (%s)\n", res->ai_family == AF_INET6 ? 6 : 4,
addrstr, res->ai_socktype == SOCK_STREAM ? "TCP" : "UDP");
res = res->ai_next;
}
freeaddrinfo(result);
return EXIT_SUCCESS;
}
int
main(int argc, char *argv[])
{
if (argc < 2) {
printf("Usage: %s DOMAIN\n", argv[0]);
return EXIT_FAILURE;
}
return lookup_host(argv[1]);
}
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