This can be used to read data from a stream channel. More...

#include <StreamAccessToken.hxx>

Inheritance diagram for dueca::StreamChannelReadToken< T >:

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Collaboration diagram for dueca::StreamChannelReadToken< T >:

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Public Member Functions
void	getAccess (const T *&data, const TimeSpec &ts)
	Makes the reference to the data valid, does not return the data's age.

void	getAccessToLatest (const T *&data, DataTimeSpec &ts)
	Get always the latest version of the data.

int	getNumWaitingSets () const
	Returns the number of data points available.

void	releaseAccess (const T *&data)
	Returns the read channel access pointer.

bool	amILagging (const TimeSpec &t)
	Determines whether the current process is behind in data reading.

bool	amILaggingMuch (const TimeSpec &t)
	Determine whether you are more than one cycle behind in reading the data.

int	getChannelDepth ()
	Figure out how many data copies are configured.

	StreamChannelReadToken (const GlobalId &holder, const NameSet &name_set, int ndc=11, Channel::TransportClass tclass=Channel::HighPriority, GenericCallback *when_valid=NULL)
	Constructor.

	~StreamChannelReadToken ()
	Destructor.

Public Member Functions inherited from dueca::ChannelReadToken
	ChannelReadToken (const GlobalId &owner, const NameSet &channelname, const std::string &dataclassname, entryid_type entryhandle=0, Channel::EntryTimeAspect time_aspect=Channel::Continuous, Channel::EntryArity arity=Channel::OnlyOneEntry, Channel::ReadingMode rmode=Channel::AdaptEventStream, double requested_span=0.2, const UCallbackOrActivity &when_valid=UCallbackOrActivity())
	Constructor, creates a token and if needed creates the associated channel end.

	ChannelReadToken (const GlobalId &owner, const NameSet &channelname, const std::string &dataclassname, entryid_type entryhandle, Channel::EntryTimeAspect time_aspect, Channel::EntryArity arity, Channel::ReadingMode rmode, double requested_span, Channel::TransportClass tclass, GenericCallback *when_valid=NULL)
	ChannelReadToken constructor, deprecated version.

	ChannelReadToken (const GlobalId &owner, const NameSet &channelname, const std::string &dataclassname, const std::string &entrylabel, Channel::EntryTimeAspect time_aspect=Channel::Continuous, Channel::EntryArity arity=Channel::OnlyOneEntry, Channel::ReadingMode rmode=Channel::AdaptEventStream, double requested_span=0.2, const UCallbackOrActivity &when_valid=UCallbackOrActivity())
	Constructor, creates a token and if needed creates the associated channel end.

	ChannelReadToken (const GlobalId &owner, const NameSet &channelname, const std::string &dataclassname, const std::string &entrylabel, Channel::EntryTimeAspect time_aspect, Channel::EntryArity arity, Channel::ReadingMode rmode, double requested_span, Channel::TransportClass tclass, GenericCallback *when_valid=NULL)
	ChannelReadToken constructor, deprecated version.

	ChannelReadToken (const GlobalId &owner, const NameSet &channelname, const std::string &dataclassname, entryid_type entryhandle, Channel::EntryTimeAspect time_aspect, Channel::EntryArity arity, Channel::ReadingMode rmode, const UCallbackOrActivity &when_valid, unsigned requested_depth)
	Constructor, creates a token and if needed creates the associated channel end.

bool	isValid ()
	Check the validity of the token.

const GlobalId &	getClientId () const
	Return the client ID.

const GlobalId &	getChannelId () const
	Return the channel ID.

bool	isSequential () const
	Data access type, sequential?

Channel::EntryTimeAspect	getTimeAspect () const
	Time aspect of read data.

DataTimeSpec	getOldestDataTime () const
	Return the span of the oldest data in the current entry.

DataTimeSpec	getLatestDataTime () const
	Return the span of the latest data in the current entry.

void	selectFirstEntry ()
	Instruct the token to start dealing with the first entry in the channel.

void	selectNextEntry ()
	Instruct the token to start dealing with the next entry.

bool	haveEntry () const
	Check that there is a valid entry to read.

const entryid_type	getEntryId () const
	Get the entry handle id.

const std::string &	getEntryLabel () const
	Get the current entry's label, if available.

unsigned int	getNumVisibleSets (const TimeTickType ts=MAX_TIMETICK) const
	Returns the number of data points older than the given time.

unsigned int	getNumVisibleSets (const DataTimeSpec ts) const
	Returns the number of data points older than the given, for any of the entries read by this token.

unsigned int	getNumVisibleSetsInEntry (const TimeTickType ts=MAX_TIMETICK) const
	Returns the number of data points older than the given time for the currently selected entry read by this token.

unsigned int	getNumVisibleSetsInEntry (const DataTimeSpec ts) const
	Returns the number of data points older than the given time, for the currently selected entry read by this token.

bool	haveVisibleSets (const TimeTickType ts=MAX_TIMETICK) const
	Returns true if there are data points visible at the given time, for any of the entries read by this token.

bool	haveVisibleSets (const DataTimeSpec ts) const
	Returns true if there are data points visible at the given time.

bool	haveVisibleSetsInEntry (const TimeTickType ts=MAX_TIMETICK) const
	Returns true if there are data points visible at the given time, for the current entry read by this token.

bool	haveVisibleSetsInEntry (const DataTimeSpec ts) const
	Returns true if there are data points visible at the given time, for the current entry read by this token.

unsigned int	flushTotalAvailableSets () const
	Flush all data in a channel for this reader.

unsigned int	flushOlderSets () const
	Flush almost all data in a channel for this reader, but leave one dataset in.

unsigned int	flushOlderSets (const TimeTickType ts) const
	Flush almost all data in a channel for this reader, but leave datasets newer than ts.

unsigned int	flushOne () const
	Flush a single dataset for this reader.

ChannelEntryInfo	getChannelEntryInfo () const
	Retrieve creation/entry information.

AccessResult	readAndStoreData (AmorphStore &s, TimeTickType &tsprev)
	Read channel data into an amorph store object.

bool	readAndPack (AmorphStore &s, DataTimeSpec &ts, const TimeSpec &tsreq=TimeSpec(0U, MAX_TIMETICK))
	Read channel data into an amorph store object.

	~ChannelReadToken ()
	Destructor.

bool	applyFunctor (DCOFunctor *fnct, TimeTickType time=MAX_TIMETICK)
	Apply a given functor to channel data.

Public Member Functions inherited from dueca::GenericToken
const GlobalId &	getTokenHolder () const
	Return the ID of the owner.

const GlobalId &	getChannelId () const
	Return the ID of the channel.

const NameSet &	getName () const
	Return the local name specified for the token.

const std::string &	getDataClassName () const
	Return the data class name.

uint32_t	getDataClassMagic () const
	Access the data class magic.

virtual	~GenericToken ()
	Destructor.

	GenericToken (const GlobalId &holder, const NameSet &name, const std::string &dataclassname)
	Constructor.

template<class MFT >
std::weak_ptr< MFT >	getMetaFunctor (const std::string &fname) const
	Obtain a specific metafunctor for interaction with channel data.

Public Member Functions inherited from dueca::TriggerPuller
const std::string &	getTriggerName () const
	Find a name.

Additional Inherited Members
Public Types inherited from dueca::ChannelReadToken
enum	AccessResult { NoData , TimeSkip , DataSuccess }
	Different type of access result. More...

Protected Types inherited from dueca::TriggerPuller
typedef list< TargetData >	targetlist_type
	Combination of a target, someone to pull if requested, and the index that target needs to identify this puller.

Protected Member Functions inherited from dueca::ChannelReadToken
const void *	getAccess (TimeTickType t_request, DataTimeSpec &ts, GlobalId &origin, uint32_t magic)
	Return a void pointer to the data in the current entry.

void	releaseAccess (const void *data_ptr)
	Return the read access given previously.

void	releaseAccessKeepData (const void *data_ptr)
	Return the read access given previously, but keep the data.

void	addTarget (const boost::intrusive_ptr< TriggerTarget > &t, unsigned id)
	Override the addTarget method from the TriggerPuller class.

Protected Member Functions inherited from dueca::GenericToken
void	checkChannelEndPresent () const
	Check preconditions.

Protected Member Functions inherited from dueca::TriggerPuller
void	pull (const DataTimeSpec &ts)
	activate and notify the targets

	TriggerPuller (const std::string &name=std::string())
	Constructor.

virtual	~TriggerPuller ()
	Destructor.

virtual void	removeTarget (const TriggerTarget *target)
	Remove a target from the puller, only called by destructor.

virtual void	setTriggerName ()
	Update the name, used by ConditionAnd and ConditionOr.

Protected Attributes inherited from dueca::GenericToken
std::string	dataclassname
	name of the data type

const DataSetConverter *	converter
	Converter for the data.

uint32_t	magic_number
	magic number for the data class name claimed here

UnifiedChannel *	channel
	pointer to the channel

Protected Attributes inherited from dueca::TriggerPuller
targetlist_type	targets
	List of targets and indices.

std::bitset< MAX_MANAGERS >	activitylevels
	Index of activitymanager levels.

std::string	name
	Name, for debugging purposes.

Detailed Description

template<class T>
class dueca::StreamChannelReadToken< T >

This can be used to read data from a stream channel.

The access token objects are used in conjunction with the channel system. When a component requests access to a channel, an access token is created and returned to the component.

For the component, the accessToken acts as a key. Using the accessToken on the channel, access to the data on the channel can be got.

For the channel, the accessToken acts as an identifier. It contains the sequence number of the component, as used in the channel object, and a GlobalId of the component. These are used for accounting purposes.

Note that StreamChannelReadToken is obsolete; please use ChannelReadToken in new code.

Constructor & Destructor Documentation

◆ StreamChannelReadToken()

template<class T >

dueca::StreamChannelReadToken< T >::StreamChannelReadToken	(	const GlobalId &	holder,
		const NameSet &	name_set,
		int	ndc = 11,
		Channel::TransportClass	tclass = Channel::HighPriority,
		GenericCallback *	when_valid = NULL )

Constructor.

Constructs an access token to read the stream channel with the specified name.

Parameters

holder	ID of the requester.
name_set	NameSet with the name of the channel that you request access for.
ndc	For older, legacy applications, this represented the number of data copies held in parallel in the channel. The first module to specify this called the shots. For compatibility, in DUECA 2.0 and above this is converted to a time span in seconds for the data in the channel, by multiplying the ndc value with 0.01, the assumed most common update interval. Currently the largest value specified in the local dueca node is used.
tclass	Transport class for the channel. Current options are Regular and Bulk. Bulk is really not recommended for stream channels.
when_valid	Callback called when the token becomes valid.

◆ ~StreamChannelReadToken()

template<class T >

dueca::StreamChannelReadToken< T >::~StreamChannelReadToken ( )

Destructor.

The existence of the channel may continue, it is really destroyed when you were the last user.

Member Function Documentation

◆ getAccess()

template<class T >

void dueca::StreamChannelReadToken< T >::getAccess	(	const T *&	data,
		const TimeSpec &	ts )

Makes the reference to the data valid, does not return the data's age.

As a side effect the access to the data is registered.

Deprecated: As of July 2001, this call is deprecated. Use a StreamReader instead!

Parameters

data	Pointer will be pointing to data afterward.
ts	Time for which access is requested.

◆ getAccessToLatest()

template<class T >

void dueca::StreamChannelReadToken< T >::getAccessToLatest	(	const T *&	data,
		DataTimeSpec &	ts )

Get always the latest version of the data.

Use this only in special applications, e.g. for projection on interfaces etc.

Parameters

data	Pointer will be pointing to data afterward.
ts	Time for which access is requested.

Deprecated: As of july 2001, this call is deprecated. Use a StreamReaderLatest instead!

◆ releaseAccess()

template<class T >

void dueca::StreamChannelReadToken< T >::releaseAccess ( const T *& data )

Returns the read channel access pointer.

The data access registration is undone.

Deprecated: As of july 2001, this call is deprecated. Use a StreamReader or StreamReaderLatest instead!

◆ amILagging()

template<class T >

bool dueca::StreamChannelReadToken< T >::amILagging ( const TimeSpec & t )

Determines whether the current process is behind in data reading.

For if you can afford to skip.

Deprecated: Using this function produces more or less random results when triggering on multiple channels. Use the noScheduledBehind() function on the Activity instead.

◆ amILaggingMuch()

template<class T >

bool dueca::StreamChannelReadToken< T >::amILaggingMuch ( const TimeSpec & t )

Determine whether you are more than one cycle behind in reading the data.

Deprecated: Using this function produces more or less random results when triggering on multiple channels. Use the noScheduledBehind() function on the Activity instead.

◆ getChannelDepth()

template<class T >

int dueca::StreamChannelReadToken< T >::getChannelDepth ( )

Figure out how many data copies are configured.

Note that while there is no writer for this channel, the channel will not be prepared, and this function will return 0.

Returns: "Depth" of a channel, i.e. how many data copies it remembers.

The documentation for this class was generated from the following file:

/home/abuild/rpmbuild/BUILD/dueca-4.1.3/dueca/StreamAccessToken.hxx

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ StreamChannelReadToken()

◆ ~StreamChannelReadToken()

Member Function Documentation

◆ getAccess()

◆ getAccessToLatest()

◆ releaseAccess()

◆ amILagging()

◆ amILaggingMuch()

◆ getChannelDepth()