Function InterruptibleRecv

src/netbase.cpp:318–349

* Try to read a specified number of bytes from a socket. Please read the "see * also" section for more detail. * * @param data The buffer where the read bytes should be stored. * @param len The number of bytes to read into the specified buffer. * @param timeout The total timeout for this read. * @param sock The socket (has to be in non-blocking mode) from which to read bytes. * * @returns

 *      Sockets can be made non-blocking with Sock::SetNonBlocking().
 */
static IntrRecvError InterruptibleRecv(uint8_t* data, size_t len, std::chrono::milliseconds timeout, const Sock& sock)
{
    auto curTime{Now<SteadyMilliseconds>()};
    const auto endTime{curTime + timeout};
    while (len > 0 && curTime < endTime) {
        ssize_t ret = sock.Recv(data, len, 0); // Optimistically try the recv first
        if (ret > 0) {
            len -= ret;
            data += ret;
        } else if (ret == 0) { // Unexpected disconnection
            return IntrRecvError::Disconnected;
        } else { // Other error or blocking
            int nErr = WSAGetLastError();
            if (nErr == WSAEINPROGRESS || nErr == WSAEWOULDBLOCK || nErr == WSAEINVAL) {
                // Only wait at most MAX_WAIT_FOR_IO at a time, unless
                // we're approaching the end of the specified total timeout
                const auto remaining = std::chrono::milliseconds{endTime - curTime};
                const auto timeout = std::min(remaining, std::chrono::milliseconds{MAX_WAIT_FOR_IO});
                if (!sock.Wait(timeout, Sock::RecvEvent)) {
                    return IntrRecvError::NetworkError;
                }
            } else {
                return IntrRecvError::NetworkError;
            }
        }
        if (g_socks5_interrupt) {
            return IntrRecvError::Interrupted;
        }
        curTime = Now<SteadyMilliseconds>();
    }
    return len == 0 ? IntrRecvError::OK : IntrRecvError::Timeout;
}

/** Convert SOCKS5 reply to an error message */
static std::string Socks5ErrorString(uint8_t err)