EchoServer.cpp

// SPDX-License-Identifier: LGPL-3.0-or-later
// Copyright © 2020-2021 Florian Fischer
#include <sys/types.h>

#include <cerrno>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <string>

#include "Common.hpp"
#include "Runtime.hpp"
#include "emper-common.h"
#include "io.hpp"

const int DECIMAL = 10;
const std::string HOST = "0.0.0.0";
const int PORT = 12345;

auto main(int argc, char* argv[]) -> int {
	int port = PORT;
	std::string host = HOST;

	if (argc > 2) {
		std::cerr << "Usage: " << argv[0] << " [port]" << std::endl;
		exit(EXIT_FAILURE);
	}

	if (argc > 1) {
		long aport = strtol(argv[1], nullptr, DECIMAL);
		assert(aport <= INT_MAX && aport >= INT_MIN);
		port = (int)aport;
	}

	std::cout << "Echoserver listening on " << host << ":" << port << std::endl;

	Runtime runtime;
	auto* listener = emper::io::tcp_listener(host, port, [](int socket) {
		// NOLINTNEXTLINE(modernize-avoid-c-arrays)
		char buf[1024];
		for (;;) {
			ssize_t bytes_recv = emper::io::recvAndWait(socket, buf, sizeof(buf), 0);
			if (unlikely(bytes_recv <= 0)) {
				// socket was shutdown
				if (bytes_recv < 0) {
					LOGE("server read failed:" << strerror(errno));
				}

			finish:
				emper::io::closeAndForget(socket);
				return;
			}

			if (unlikely(bytes_recv == 5 && strncmp("quit\n", buf, bytes_recv) == 0)) {
				exit(EXIT_SUCCESS);
			}

			ssize_t bytes_send = emper::io::sendAndWait(socket, buf, bytes_recv, MSG_NOSIGNAL, true);
			if (unlikely(bytes_recv != bytes_send)) {
				LOGE("server send failed: " << strerror(errno));
				goto finish;
			}
		}
	});

	if (!listener) {
		exit(EXIT_FAILURE);
	}

	runtime.scheduleFromAnywhere(*listener);

	runtime.waitUntilFinished();

	return EXIT_FAILURE;
}