ladybird/Userland/Utilities/host.cpp
brapru 8b370f988b host: Use AK/IPv4Address to determine if argument is host/ip
It's a bit cleaner to just rely on AK/IPv4Address' ability to determine
the validity of the given input. If a valid IP address is not returned,
then input will be processed as a hostname.
2022-04-16 22:16:29 -07:00

51 lines
1.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/IPv4Address.h>
#include <LibCore/ArgsParser.h>
#include <LibCore/System.h>
#include <LibMain/Main.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <netinet/in.h>
#include <string.h>
ErrorOr<int> serenity_main(Main::Arguments args)
{
TRY(Core::System::pledge("stdio unix"));
char const* 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(args);
// If input looks like an IPv4 address, we should do a reverse lookup.
auto ip_address = IPv4Address::from_string(name_or_ip);
if (ip_address.has_value()) {
// Okay, let's do a reverse lookup.
auto addr = ip_address.value().to_in_addr_t();
auto* hostent = gethostbyaddr(&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];
char const* ip_str = inet_ntop(AF_INET, hostent->h_addr_list[0], buffer, sizeof(buffer));
outln("{} is {}", name_or_ip, ip_str);
return 0;
}