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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/ArgsParser.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
int main(int argc, char** argv)
{
if (pledge("stdio unix", nullptr) < 0) {
perror("pledge");
return 1;
}
const char* name_or_ip = nullptr;
Core::ArgsParser args_parser;
args_parser.set_general_help("Convert between domain name and IPv4 address.");
args_parser.add_positional_argument(name_or_ip, "Domain name or IPv4 address", "name");
args_parser.parse(argc, argv);
// If input looks like an IPv4 address, we should do a reverse lookup.
struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(53);
int rc = inet_pton(AF_INET, name_or_ip, &addr.sin_addr);
if (rc == 1) {
// Okay, let's do a reverse lookup.
auto* hostent = gethostbyaddr(&addr.sin_addr, sizeof(in_addr), AF_INET);
if (!hostent) {
warnln("Reverse lookup failed for '{}'", name_or_ip);
return 1;
}
outln("{} is {}", name_or_ip, hostent->h_name);
return 0;
}
auto* hostent = gethostbyname(name_or_ip);
if (!hostent) {
warnln("Lookup failed for '{}'", name_or_ip);
return 1;
}
char buffer[INET_ADDRSTRLEN];
const char* ip_str = inet_ntop(AF_INET, hostent->h_addr_list[0], buffer, sizeof(buffer));
outln("{} is {}", name_or_ip, ip_str);
return 0;
}
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