Network/Network/IcmpClientImpl.cpp

#include "IcmpClientImpl.h"
#include <chrono>


namespace Network {

IcmpClientImpl::IcmpClientImpl() :
	m_socket(m_ioContext, asio::ip::icmp::v4()),
	m_done(false)
{
	StartReceive();
	m_thread = std::thread([&] { m_ioContext.run(); });

#ifdef __linux__
	pthread_setname_np(m_thread.native_handle(), "IcmpClientImpl");
#endif
}

IcmpClientImpl::~IcmpClientImpl()
{
	m_ioContext.stop();
	m_thread.join();
}

bool IcmpClientImpl::Ping(const std::string& targetAddress)
{
	m_done = false;

	SendEchoRequest(asio::ip::icmp::endpoint(asio::ip::address::from_string(targetAddress), 0), std::string());

	std::unique_lock<std::mutex> lock(m_mutex);
	if (m_condition.wait_for(lock, std::chrono::seconds(3), [&] { return m_done; }))
		return true;

	return false;
}

void IcmpClientImpl::SendEchoRequest(const asio::ip::icmp::endpoint& targetEndpoint, const std::string& data)
{
	Internal::IcmpHeader echoRequest;
	echoRequest.type(Internal::IcmpHeader::echo_request);
	echoRequest.code(0);
	echoRequest.identifier(GetIdentifier());
	echoRequest.sequence_number(0);
	Internal::ComputeChecksum(echoRequest, data.begin(), data.end());

	asio::streambuf requestBuffer;
	std::ostream os(&requestBuffer);
	os << echoRequest << data;

	m_socket.send_to(requestBuffer.data(), targetEndpoint);
}

void IcmpClientImpl::StartReceive()
{
	m_replyBuffer.consume(m_replyBuffer.size());
	m_socket.async_receive(m_replyBuffer.prepare(65536), std::bind(&IcmpClientImpl::HandleReceive, this, std::placeholders::_1, std::placeholders::_2));
}

void IcmpClientImpl::HandleReceive(const asio::error_code& error, std::size_t length)
{
	m_replyBuffer.commit(length);

	std::istream is(&m_replyBuffer);
	Internal::Ipv4Header ipv4Header;
	Internal::IcmpHeader icmpHeader;
	is >> ipv4Header >> icmpHeader;

	if (is && icmpHeader.type() == Internal::IcmpHeader::echo_reply
	       && icmpHeader.identifier() == GetIdentifier()
	       && icmpHeader.sequence_number() == 0)
	{
		m_done = true;
		m_condition.notify_all();
	}

	StartReceive();
}

unsigned short IcmpClientImpl::GetIdentifier()
{
	return static_cast<unsigned short>(::getpid());
}

} // namespace Network