libreoffice-online/wsd/LOOLWebSocket.hpp
Jan Holesovsky 9842f3239f Make sure we don't use the jitter / delay in production builds.
And default to 0 even for debug; who wants to use that for debugging, they
know what to do.

Change-Id: I23dd0c5f806b2b31a883b7a2b8d822ea8c0bb6c5
2016-11-28 11:31:06 +01:00

147 lines
4.7 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef INCLUDED_LOOLWEBSOCKET_HPP
#define INCLUDED_LOOLWEBSOCKET_HPP
#include <cstdlib>
#include <mutex>
#include <thread>
#include <Poco/Net/WebSocket.h>
#include <Common.hpp>
#include <Protocol.hpp>
#include <Log.hpp>
/// WebSocket that is thread safe, and handles large frames transparently.
/// Careful - sendFrame and receiveFrame are _not_ virtual,
/// we need to make sure that we use LOOLWebSocket all over the place.
/// It would be a kind of more natural to encapsulate Poco::Net::WebSocket
/// instead of inheriting (from that reason,) but that would requite much
/// larger code changes.
class LOOLWebSocket : public Poco::Net::WebSocket
{
private:
std::mutex _mutex;
#if ENABLE_DEBUG
std::chrono::milliseconds getWebSocketDelay()
{
unsigned long baseDelay = 0;
unsigned long jitter = 0;
if (std::getenv("LOOL_WS_DELAY"))
{
baseDelay = std::stoul(std::getenv("LOOL_WS_DELAY"));
}
if (std::getenv("LOOL_WS_JITTER"))
{
jitter = std::stoul(std::getenv("LOOL_WS_JITTER"));
}
return std::chrono::milliseconds(baseDelay + (jitter > 0 ? (std::rand() % jitter) : 0));
}
#endif
public:
LOOLWebSocket(const Socket& socket) :
Poco::Net::WebSocket(socket)
{
}
LOOLWebSocket(Poco::Net::HTTPServerRequest& request,
Poco::Net::HTTPServerResponse& response) :
Poco::Net::WebSocket(request, response)
{
}
LOOLWebSocket(Poco::Net::HTTPClientSession& cs,
Poco::Net::HTTPRequest& request,
Poco::Net::HTTPResponse& response) :
Poco::Net::WebSocket(cs, request, response)
{
}
LOOLWebSocket(Poco::Net::HTTPClientSession& cs,
Poco::Net::HTTPRequest& request,
Poco::Net::HTTPResponse& response,
Poco::Net::HTTPCredentials& credentials) :
Poco::Net::WebSocket(cs, request, response, credentials)
{
}
/// Wrapper for Poco::Net::WebSocket::receiveFrame() that handles PING frames
/// (by replying with a PONG frame) and PONG frames. PONG frames are ignored.
/// Should we also factor out the handling of non-final and continuation frames into this?
int receiveFrame(char* buffer, const int length, int& flags)
{
#if ENABLE_DEBUG
// Delay receiving the frame
std::this_thread::sleep_for(getWebSocketDelay());
#endif
// Timeout given is in microseconds.
static const Poco::Timespan waitTime(POLL_TIMEOUT_MS * 1000);
while (poll(waitTime, Poco::Net::Socket::SELECT_READ))
{
const int n = Poco::Net::WebSocket::receiveFrame(buffer, length, flags);
if ((flags & WebSocket::FRAME_OP_BITMASK) == WebSocket::FRAME_OP_PING)
{
sendFrame(buffer, n, WebSocket::FRAME_FLAG_FIN | WebSocket::FRAME_OP_PONG);
}
else if ((flags & WebSocket::FRAME_OP_BITMASK) == WebSocket::FRAME_OP_PONG)
{
// In case we do send pongs in the future.
}
else
{
return n;
}
}
return -1;
}
/// Wrapper for Poco::Net::WebSocket::sendFrame() that handles large frames.
int sendFrame(const char* buffer, const int length, const int flags = FRAME_TEXT)
{
#if ENABLE_DEBUG
// Delay sending the frame
std::this_thread::sleep_for(getWebSocketDelay());
#endif
std::unique_lock<std::mutex> lock(_mutex);
if (length >= LARGE_MESSAGE_SIZE)
{
const std::string nextmessage = "nextmessage: size=" + std::to_string(length);
Poco::Net::WebSocket::sendFrame(nextmessage.data(), nextmessage.size());
LOG_TRC("Message is long, sent " + nextmessage);
}
const int result = Poco::Net::WebSocket::sendFrame(buffer, length, flags);
lock.unlock();
if (result != length)
{
LOG_ERR("Sent incomplete message, expected " << length << " bytes but sent " << result <<
" while sending: " << LOOLProtocol::getAbbreviatedMessage(buffer, length));
}
else
{
LOG_TRC("Sent frame: " << LOOLProtocol::getAbbreviatedMessage(buffer, length));
}
return result;
}
};
#endif
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */