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// *****************************************************************************
// * This file is part of the FreeFileSync project. It is distributed under *
// * GNU General Public License: https://www.gnu.org/licenses/gpl-3.0 *
// * Copyright (C) Zenju (zenju AT freefilesync DOT org) - All Rights Reserved *
// *****************************************************************************
#ifndef SOCKET_H_23498325972583947678456437
#define SOCKET_H_23498325972583947678456437
#include <zen/zstring.h>
#include "sys_error.h"
#include <unistd.h> //close
#include <sys/socket.h>
#include <netdb.h> //getaddrinfo
namespace zen
{
#define THROW_LAST_SYS_ERROR_WSA(functionName) \
do { const ErrorCode ecInternal = getLastError(); throw SysError(formatSystemError(functionName, ecInternal)); } while (false)
//Winsock needs to be initialized before calling any of these functions! (WSAStartup/WSACleanup)
class Socket //throw SysError
{
public:
Socket(const Zstring& server, const Zstring& serviceName) //throw SysError
{
::addrinfo hints = {};
hints.ai_socktype = SOCK_STREAM; //we *do* care about this one!
hints.ai_flags = AI_ADDRCONFIG; //save a AAAA lookup on machines that can't use the returned data anyhow
::addrinfo* servinfo = nullptr;
ZEN_ON_SCOPE_EXIT(if (servinfo) ::freeaddrinfo(servinfo));
const int rcGai = ::getaddrinfo(server.c_str(), serviceName.c_str(), &hints, &servinfo);
if (rcGai != 0)
throw SysError(formatSystemError(L"getaddrinfo", replaceCpy(_("Error Code %x"), L"%x", numberTo<std::wstring>(rcGai)), utfTo<std::wstring>(::gai_strerror(rcGai))));
if (!servinfo)
throw SysError(L"getaddrinfo: empty server info");
auto getConnectedSocket = [&](const auto& /*::addrinfo*/ ai)
{
SocketType testSocket = ::socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol);
if (testSocket == invalidSocket)
THROW_LAST_SYS_ERROR_WSA(L"socket");
ZEN_ON_SCOPE_FAIL(closeSocket(testSocket));
if (::connect(testSocket, ai.ai_addr, static_cast<int>(ai.ai_addrlen)) != 0)
THROW_LAST_SYS_ERROR_WSA(L"connect");
return testSocket;
};
std::optional<SysError> firstError;
for (const auto* /*::addrinfo*/ si = servinfo; si; si = si->ai_next)
try
{
socket_ = getConnectedSocket(*si); //throw SysError; pass ownership
return;
}
catch (const SysError& e) { if (!firstError) firstError = e; }
throw* firstError; //list was not empty, so there must have been an error!
}
~Socket() { closeSocket(socket_); }
using SocketType = int;
SocketType get() const { return socket_; }
private:
Socket (const Socket&) = delete;
Socket& operator=(const Socket&) = delete;
static const SocketType invalidSocket = -1;
static void closeSocket(SocketType s) { ::close(s); }
SocketType socket_ = invalidSocket;
};
}
#endif //SOCKET_H_23498325972583947678456437
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