/*-
* Copyright (c) 2011, 2012, 2013, 2014 Spectra Logic Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* Authors: Justin T. Gibbs (Spectra Logic Corporation)
*
* $FreeBSD$
*/
/**
* \file devdctl_consumer.h
*/
#ifndef _DEVDCTL_CONSUMER_H_
#define _DEVDCTL_CONSUMER_H_
/*============================ Namespace Control =============================*/
namespace DevdCtl
{
/*=========================== Forward Declarations ===========================*/
class Event;
/*============================ Class Declarations ============================*/
/*----------------------------- DevdCtl::Consumer ----------------------------*/
/**
*/
class Consumer
{
public:
Consumer(Event::BuildMethod *defBuilder = NULL,
EventFactory::Record *regEntries = NULL,
size_t numEntries = 0);
virtual ~Consumer();
bool Connected() const;
/**
* Return file descriptor useful for client's wishing to poll(2)
* for new events.
*/
int GetPollFd();
/**
* Queue an event for deferred processing or replay.
*/
bool SaveEvent(const Event &event);
/**
* Reprocess any events saved via the SaveEvent() facility.
*
* \param discardUnconsumed If true, events that are not consumed
* during replay are discarded.
*/
void ReplayUnconsumedEvents(bool discardUnconsumed);
/** Return an event, if one is available. */
Event *NextEvent();
/**
* Extract events and invoke each event's Process method.
*/
void ProcessEvents();
/** Discard all data pending in m_devdSockFD. */
void FlushEvents();
/**
* Test for data pending in m_devdSockFD
*
* \return True if data is pending. Otherwise false.
*/
bool EventsPending();
/**
* Open a connection to devd's unix domain socket.
*
* \return True if the connection attempt is successsful. Otherwise
* false.
*/
bool ConnectToDevd();
/**
* Close a connection (if any) to devd's unix domain socket.
*/
void DisconnectFromDevd();
EventFactory GetFactory();
protected:
/**
* \brief Reads the most recent record
*
* On error, "" is returned, and errno will be set by the OS
*
* \returns A string containing the record
*/
std::string ReadEvent();
enum {
/*
* The maximum event size supported by libdevdctl.
*/
MAX_EVENT_SIZE = 8192,
};
static const char s_devdSockPath[];
/**
* File descriptor representing the unix domain socket
* connection with devd.
*/
int m_devdSockFD;
EventFactory m_eventFactory;
/** Queued events for replay. */
EventList m_unconsumedEvents;
/**
* Flag controlling whether events can be queued. This boolean
* is set during event replay to ensure that previosuly deferred
* events are not requeued and thus retained forever.
*/
bool m_replayingEvents;
};
//- Consumer Const Public Inline Methods ---------------------------------------
inline bool
Consumer::Connected() const
{
return (m_devdSockFD != -1);
}
//- Consumer Public Inline Methods ---------------------------------------------
inline int
Consumer::GetPollFd()
{
return (m_devdSockFD);
}
inline EventFactory
Consumer::GetFactory()
{
return (m_eventFactory);
}
} // namespace DevdCtl
#endif /* _DEVDCTL_CONSUMER_H_ */
