Files
pvAccess/pvAccessApp/server/beaconEmitter.cpp
2012-07-24 23:00:20 +02:00

151 lines
3.9 KiB
C++

/**
* Copyright - See the COPYRIGHT that is included with this distribution.
* pvAccessCPP is distributed subject to a Software License Agreement found
* in file LICENSE that is included with this distribution.
*/
#ifdef _WIN32
#define NOMINMAX
#endif
#include <pv/beaconEmitter.h>
#include <pv/serializationHelper.h>
#include <pv/logger.h>
#include <algorithm>
#include <pv/serverContext.h>
using namespace std;
using namespace epics::pvData;
namespace epics { namespace pvAccess {
const float BeaconEmitter::EPICS_CA_MIN_BEACON_PERIOD = 1.0;
const float BeaconEmitter::EPICS_CA_MIN_BEACON_COUNT_LIMIT = 3.0;
//BeaconEmitter::BeaconEmitter(Transport::shared_pointer const & transport, ServerContextImpl::shared_pointer const & context) :
BeaconEmitter::BeaconEmitter(Transport::shared_pointer const & transport, std::tr1::shared_ptr<ServerContextImpl>& context) :
_transport(transport),
_beaconSequenceID(0),
_startupTime(),
_fastBeaconPeriod(std::max(context->getBeaconPeriod(), EPICS_CA_MIN_BEACON_PERIOD)),
_slowBeaconPeriod(std::max(180.0, _fastBeaconPeriod)), // TODO configurable
_beaconCountLimit((int16)std::max(10.0f, EPICS_CA_MIN_BEACON_COUNT_LIMIT)), // TODO configurable
_serverAddress(*(context->getServerInetAddress())),
_serverPort(context->getServerPort()),
_serverStatusProvider(context->getBeaconServerStatusProvider()),
_timer(context->getTimer())
{
_startupTime.getCurrent();
}
BeaconEmitter::BeaconEmitter(Transport::shared_pointer const & transport, const osiSockAddr& serverAddress) :
_transport(transport),
_beaconSequenceID(0),
_startupTime(),
_fastBeaconPeriod(EPICS_CA_MIN_BEACON_PERIOD),
_slowBeaconPeriod(180.0),
_beaconCountLimit(10),
_serverAddress(serverAddress),
_serverPort(serverAddress.ia.sin_port),
_serverStatusProvider(),
_timer(new Timer("pvAccess-server timer", lowPriority))
{
_startupTime.getCurrent();
}
BeaconEmitter::~BeaconEmitter()
{
destroy();
}
void BeaconEmitter::lock()
{
//noop
}
void BeaconEmitter::unlock()
{
//noop
}
void BeaconEmitter::send(ByteBuffer* buffer, TransportSendControl* control)
{
// get server status
PVField::shared_pointer serverStatus;
if(_serverStatusProvider.get())
{
try
{
serverStatus = _serverStatusProvider->getServerStatusData();
}
catch (...) {
// we have to proctect internal code from external implementation...
LOG(logLevelDebug, "BeaconServerStatusProvider implementation thrown an exception.");
}
}
// send beacon
control->startMessage((int8)0, (sizeof(int16)+2*sizeof(int32)+128+sizeof(int16))/sizeof(int8));
buffer->putShort(_beaconSequenceID);
buffer->putLong((int64)_startupTime.getSecondsPastEpoch());
buffer->putInt((int32)_startupTime.getNanoSeconds());
// NOTE: is it possible (very likely) that address is any local address ::ffff:0.0.0.0
encodeAsIPv6Address(buffer, &_serverAddress);
buffer->putShort((int16)_serverPort);
if (serverStatus)
{
// introspection interface + data
serverStatus->getField()->serialize(buffer, control);
serverStatus->serialize(buffer, control);
}
else
{
SerializationHelper::serializeNullField(buffer, control);
}
control->flush(true);
// increment beacon sequence ID
_beaconSequenceID++;
reschedule();
}
void BeaconEmitter::timerStopped()
{
//noop
}
void BeaconEmitter::destroy()
{
_timer->cancel(shared_from_this());
}
void BeaconEmitter::start()
{
_timer->scheduleAfterDelay(shared_from_this(), 0.0);
}
void BeaconEmitter::reschedule()
{
const double period = (_beaconSequenceID >= _beaconCountLimit) ? _slowBeaconPeriod : _fastBeaconPeriod;
if (period > 0)
{
_timer->scheduleAfterDelay(shared_from_this(), period);
}
}
void BeaconEmitter::callback()
{
// requires this instance has already a valid pointer to this
TransportSender::shared_pointer thisSender = shared_from_this();
_transport->enqueueSendRequest(thisSender);
}
}}