ZeroTierOne/node/DeferredPackets.hpp

100 lines
2.8 KiB
C++

/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2015 ZeroTier, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#ifndef ZT_DEFERREDPACKETS_HPP
#define ZT_DEFERREDPACKETS_HPP
#include "Constants.hpp"
#include "SharedPtr.hpp"
#include "Mutex.hpp"
#include "DeferredPackets.hpp"
#include "BinarySemaphore.hpp"
/**
* Maximum number of deferred packets
*/
#define ZT_DEFFEREDPACKETS_MAX 1024
namespace ZeroTier {
class IncomingPacket;
class RuntimeEnvironment;
/**
* Deferred packets
*
* IncomingPacket can defer its decoding this way by enqueueing itself here.
* When this is done, deferredDecode() is called later. This is done for
* operations that may be expensive to allow them to potentially be handled
* in the background or rate limited to maintain quality of service for more
* routine operations.
*/
class DeferredPackets
{
public:
DeferredPackets(const RuntimeEnvironment *renv);
~DeferredPackets();
/**
* Enqueue a packet
*
* Since packets enqueue themselves, they call it with 'this' and we wrap
* them in a SharedPtr<>. This is safe as SharedPtr<> is introspective and
* supports this. This should not be called from any other code outside
* IncomingPacket.
*
* @param pkt Packet to process later (possibly in the background)
* @return False if queue is full
*/
bool enqueue(IncomingPacket *pkt);
/**
* Wait for and then process a deferred packet
*
* If we are shutting down (in destructor), this returns -1 and should
* not be called again. Otherwise it returns the number of packets
* processed.
*
* @return Number processed or -1 if shutting down
*/
int process();
private:
SharedPtr<IncomingPacket> _q[ZT_DEFFEREDPACKETS_MAX];
const RuntimeEnvironment *const RR;
unsigned long _readPtr;
unsigned long _writePtr;
volatile int _waiting;
volatile bool _die;
Mutex _q_m;
BinarySemaphore _q_s;
};
} // namespace ZeroTier
#endif