freebsd-nq/lib/libdevdctl/event.h
2016-05-30 19:25:00 +00:00

424 lines
11 KiB
C++

/*-
* Copyright (c) 2011, 2012, 2013, 2016 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_event.h
*
* \brief Class hierarchy used to express events received via
* the devdctl API.
*/
#ifndef _DEVDCTL_EVENT_H_
#define _DEVDCTL_EVENT_H_
/*============================ Namespace Control =============================*/
namespace DevdCtl
{
/*=========================== Forward Declarations ===========================*/
class EventFactory;
/*============================= Class Definitions ============================*/
/*-------------------------------- NVPairMap ---------------------------------*/
/**
* NVPairMap is a specialization of the standard map STL container.
*/
typedef std::map<std::string, std::string> NVPairMap;
/*----------------------------------- Event ----------------------------------*/
/**
* \brief Container for the name => value pairs that comprise the content of
* a device control event.
*
* All name => value data for events can be accessed via the Contains()
* and Value() methods. name => value pairs for data not explicitly
* received as a name => value pair are synthesized during parsing. For
* example, ATTACH and DETACH events have "device-name" and "parent"
* name => value pairs added.
*/
class Event
{
friend class EventFactory;
public:
/** Event type */
enum Type {
/** Generic event notification. */
NOTIFY = '!',
/** A driver was not found for this device. */
NOMATCH = '?',
/** A bus device instance has been added. */
ATTACH = '+',
/** A bus device instance has been removed. */
DETACH = '-'
};
/**
* Factory method type to construct an Event given
* the type of event and an NVPairMap populated from
* the event string received from devd.
*/
typedef Event* (BuildMethod)(Type, NVPairMap &, const std::string &);
/** Generic Event object factory. */
static BuildMethod Builder;
static Event *CreateEvent(const EventFactory &factory,
const std::string &eventString);
/**
* Returns the devname, if any, associated with the event
*
* \param name Devname, returned by reference
* \return True iff the event contained a devname
*/
virtual bool DevName(std::string &name) const;
/**
* Returns the absolute pathname of the device associated with this
* event.
*
* \param name Devname, returned by reference
* \return True iff the event contained a devname
*/
bool DevPath(std::string &path) const;
/**
* Returns true iff this event refers to a disk device
*/
bool IsDiskDev() const;
/** Returns the physical path of the device, if any
*
* \param path Physical path, returned by reference
* \return True iff the event contains a device with a physical
* path
*/
bool PhysicalPath(std::string &path) const;
/**
* Provide a user friendly string representation of an
* event type.
*
* \param type The type of event to map to a string.
*
* \return A user friendly string representing the input type.
*/
static const char *TypeToString(Type type);
/**
* Determine the availability of a name => value pair by name.
*
* \param name The key name to search for in this event instance.
*
* \return true if the specified key is available in this
* event, otherwise false.
*/
bool Contains(const std::string &name) const;
/**
* \param key The name of the key for which to retrieve its
* associated value.
*
* \return A const reference to the string representing the
* value associated with key.
*
* \note For key's with no registered value, the empty string
* is returned.
*/
const std::string &Value(const std::string &key) const;
/**
* Get the type of this event instance.
*
* \return The type of this event instance.
*/
Type GetType() const;
/**
* Get the original DevdCtl event string for this event.
*
* \return The DevdCtl event string.
*/
const std::string &GetEventString() const;
/**
* Convert the event instance into a string suitable for
* printing to the console or emitting to syslog.
*
* \return A string of formatted event data.
*/
std::string ToString() const;
/**
* Pretty-print this event instance to cout.
*/
void Print() const;
/**
* Pretty-print this event instance to syslog.
*
* \param priority The logging priority/facility.
* See syslog(3).
*/
void Log(int priority) const;
/**
* Create and return a fully independent clone
* of this event.
*/
virtual Event *DeepCopy() const;
/** Destructor */
virtual ~Event();
/**
* Interpret and perform any actions necessary to
* consume the event.
*
* \return True if this event should be queued for later reevaluation
*/
virtual bool Process() const;
/**
* Get the time that the event was created
*/
timeval GetTimestamp() const;
/**
* Add a timestamp to the event string, if one does not already exist
* TODO: make this an instance method that operates on the std::map
* instead of the string. We must fix zfsd's CaseFile serialization
* routines first, so that they don't need the raw event string.
*
* \param[in,out] eventString The devd event string to modify
*/
static void TimestampEventString(std::string &eventString);
/**
* Access all parsed key => value pairs.
*/
const NVPairMap &GetMap() const;
protected:
/** Table entries used to map a type to a user friendly string. */
struct EventTypeRecord
{
Type m_type;
const char *m_typeName;
};
/**
* Constructor
*
* \param type The type of event to create.
*/
Event(Type type, NVPairMap &map, const std::string &eventString);
/** Deep copy constructor. */
Event(const Event &src);
/** Always empty string returned when NVPairMap lookups fail. */
static const std::string s_theEmptyString;
/** Unsorted table of event types. */
static EventTypeRecord s_typeTable[];
/** The type of this event. */
const Type m_type;
/**
* Event attribute storage.
*
* \note Although stored by reference (since m_nvPairs can
* never be NULL), the NVPairMap referenced by this field
* is dynamically allocated and owned by this event object.
* m_nvPairs must be deleted at event destruction.
*/
NVPairMap &m_nvPairs;
/**
* The unaltered event string, as received from devd, used to
* create this event object.
*/
std::string m_eventString;
private:
/**
* Ingest event data from the supplied string.
*
* \param[in] eventString The string of devd event data to parse.
* \param[out] nvpairs Returns the parsed data
*/
static void ParseEventString(Type type, const std::string &eventString,
NVPairMap &nvpairs);
};
inline Event::Type
Event::GetType() const
{
return (m_type);
}
inline const std::string &
Event::GetEventString() const
{
return (m_eventString);
}
inline const NVPairMap &
Event::GetMap() const
{
return (m_nvPairs);
}
/*--------------------------------- EventList --------------------------------*/
/**
* EventList is a specialization of the standard list STL container.
*/
typedef std::list<Event *> EventList;
/*-------------------------------- DevfsEvent --------------------------------*/
class DevfsEvent : public Event
{
public:
/** Specialized Event object factory for Devfs events. */
static BuildMethod Builder;
virtual Event *DeepCopy() const;
/**
* Interpret and perform any actions necessary to
* consume the event.
* \return True if this event should be queued for later reevaluation
*/
virtual bool Process() const;
bool IsWholeDev() const;
virtual bool DevName(std::string &name) const;
protected:
/**
* Given the device name of a disk, determine if the device
* represents the whole device, not just a partition.
*
* \param devName Device name of disk device to test.
*
* \return True if the device name represents the whole device.
* Otherwise false.
*/
static bool IsWholeDev(const std::string &devName);
/** DeepCopy Constructor. */
DevfsEvent(const DevfsEvent &src);
/** Constructor */
DevfsEvent(Type, NVPairMap &, const std::string &);
};
/*--------------------------------- GeomEvent --------------------------------*/
class GeomEvent : public Event
{
public:
/** Specialized Event object factory for GEOM events. */
static BuildMethod Builder;
virtual Event *DeepCopy() const;
virtual bool DevName(std::string &name) const;
const std::string &DeviceName() const;
protected:
/** Constructor */
GeomEvent(Type, NVPairMap &, const std::string &);
/** Deep copy constructor. */
GeomEvent(const GeomEvent &src);
std::string m_devname;
};
/*--------------------------------- ZfsEvent ---------------------------------*/
class ZfsEvent : public Event
{
public:
/** Specialized Event object factory for ZFS events. */
static BuildMethod Builder;
virtual Event *DeepCopy() const;
virtual bool DevName(std::string &name) const;
const std::string &PoolName() const;
Guid PoolGUID() const;
Guid VdevGUID() const;
protected:
/** Constructor */
ZfsEvent(Type, NVPairMap &, const std::string &);
/** Deep copy constructor. */
ZfsEvent(const ZfsEvent &src);
Guid m_poolGUID;
Guid m_vdevGUID;
};
//- ZfsEvent Inline Public Methods --------------------------------------------
inline const std::string&
ZfsEvent::PoolName() const
{
/* The pool name is reported as the subsystem of ZFS events. */
return (Value("subsystem"));
}
inline Guid
ZfsEvent::PoolGUID() const
{
return (m_poolGUID);
}
inline Guid
ZfsEvent::VdevGUID() const
{
return (m_vdevGUID);
}
} // namespace DevdCtl
#endif /*_DEVDCTL_EVENT_H_ */