SFBNet Class Reference

Class supporting 'service gradient routing' via the Net. More...

#include <SFBNet.h>

Collaboration diagram for SFBNet:


Data Structures
struct	Entry
Public Types
enum	Sizes { MAX_TOTAL_SVCS = 64, MAX_LOCAL_SVCS = 32, MAX_RETURN_ROUTE_LENGTH = 100 }
	Scaling limits for SFBNet. More...
Public Member Functions
bool	shouldTakeFirstTie ()
	Access tie-breaking strategy for equal-length routing decisions.
void	setShouldTakeFirstTie (bool on)
	Control tie-breaking strategy for equal-length routing decisions.
void	begin ()
	Initializes the Net, by registering the 'N' reflex and starting the broadcast alarm.
bool	isActive ()
	`true` if the most-recent call to begin() is newer than the most-recent call to end().
void	end ()
	Stops the Net.
void	offer (u8 service)
	Specifies that service is now locally provided.
bool	withhold (u8 service)
	Specifies that service is not (or no longer) locally provided.
bool	isOfferedByNode (u8 service)
	Is service currently being offered locally by this node?
bool	isOfferedByNet (u8 service)
	Is service being currently offered anywhere on the grid (as far as we know)?
void	openServiceStream (u8 service)
	Opens a "connection" with a service provider.
void	printf (const char *fmt,...)
	Prints formatted output to the currently open service.
void	vprintf (const char *fmt, va_list &ap)
	Prints formatted output to the currently open service.
void	printf (u8 service, const char *fmt,...)
	Prints formatted output to a provider of service, if any.
void	setBroadcastPeriod (u32 millis)
	Sets the broadcast period to approximately millis.
void	setHorizon (u32 distance)
	Sets the TTL ('Time To Live') horizon for all Net packets originating at this node to distance.
u32	getHorizon ()
	Gets the TTL ('Time To Live') horizon used for all Net packets originating at this node.
u32	getServiceStreamFace ()
	Get the virtual face used for printing to the internal packet buffer.
bool	neighborActive (u8 face)
	Returns `true` if we have recently heard SFBNet activity from `face`.
void	printPath (u8 toFace, bool skipFirst=true)
void	dump (u8 face, const u8 *prefix=0)
	Log internal state to face for debugging.

Detailed Description

Class supporting 'service gradient routing' via the Net.

Allows a sketch to offer 'services' to a (region of) connected boards. Service requests from the network appear as simple reflex triggerings on the service-offering board; replies generated during reflex processing can be automatically reverse-routed to the requesting board.

Since:: 0.9.18

Member Enumeration Documentation

enum SFBNet::Sizes

Scaling limits for SFBNet.

Increasing these values increases the SFBNet RAM footprint.

See also:: setHorizon(u32) and setBroadcastPeriod(u32) for runtime-settable scaling parameters.

Enumerator:

MAX_TOTAL_SVCS	Maximum services a given node can route to. RAM increases at 9*this bytes.
MAX_LOCAL_SVCS	Maximum services a given node can provide. RAM increases at this bytes.
MAX_RETURN_ROUTE_LENGTH	Maximum hops allowed in a return route. RAM increases at this bytes.

Member Function Documentation

u32 SFBNet::getHorizon ( ) [inline]

Gets the TTL ('Time To Live') horizon used for all Net packets originating at this node.

See also:: setHorizon(u32)

bool SFBNet::isOfferedByNet ( u8 service )

Is service being currently offered anywhere on the grid (as far as we know)?

Returns:: true iff it is.

See also:: isOfferedByNode(u8 service) for a mechanism to determine if service is offered specifically by the current node.

bool SFBNet::isOfferedByNode ( u8 service )

Is service currently being offered locally by this node?

Returns:: true iff it is.

See also:: isOfferedByNet(u8 service) for a mechanism to determine if service is offered anywhere in the Net (not just locally).

void SFBNet::offer ( u8 service )

Specifies that service is now locally provided.

Changes nothing if service was already locally provided.

Blinks:: E_API_RESOURCE_EXHAUSTED if there's no more room to offer local services

See also:: MAX_LOCAL_SVCS
withhold(u8)

Examples:: netled.cpp.

void SFBNet::openServiceStream ( u8 service )

Opens a "connection" with a service provider.

That is, it sets the currently selected service to service, such that, when a newline is printed, the current contents of the internal packet buffer are shipped out to a provider of service.

void SFBNet::printf	(	const char *	fmt,
			...
	)

Prints formatted output to the currently open service.

See also:: openServiceStream(u8)

Examples:: netled.cpp.

void SFBNet::setBroadcastPeriod ( u32 millis )

Sets the broadcast period to approximately millis.

Actual range of values is about 0.25 seconds to about one minute, at a granularity of about a quarter second; millis values outside that range will be clipped to the nearest value. Default value is about 5 seconds. A smaller period responds faster to node connectivity changes, but increases overall network traffic.

void SFBNet::setHorizon ( u32 distance )

Sets the TTL ('Time To Live') horizon for all Net packets originating at this node to distance.

Default value 6. Increasing the TTL increases the effective 'radius' of the Net, but greatly increases the amount of traffic sent during broadcasts.

Blinks:: E_API_MAX_RANGE if distance is not less than half of MAX_RETURN_ROUTE_LENGTH.

void SFBNet::setShouldTakeFirstTie ( bool on ) [inline]

Control tie-breaking strategy for equal-length routing decisions.

Determines whether shortest-direction ties should be resolved in favor of the first such direction encountered (on set to true) or by a random choice (on set to false).

See also:: shouldTakeFirstTie()

bool SFBNet::shouldTakeFirstTie ( ) [inline]

Access tie-breaking strategy for equal-length routing decisions.

Returns:: true if configured to route to the first-encountered among all equally shortest directions; false if picking randomly among all such choices.

See also:: setShouldTakeFirstTie(bool)

void SFBNet::vprintf	(	const char *	fmt,
		va_list &	ap
	)

Prints formatted output to the currently open service.

See also:: openServiceStream(u8)

bool SFBNet::withhold ( u8 service )

Specifies that service is not (or no longer) locally provided.

Returns:: true iff service had been being offered before this call.

See also:: offer(u8)

Examples:: netled.cpp.

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

src/include/SFBNet.h
src/components/library/SFBNet.cpp

SFBNet Class Reference

Data Structures

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

Member Function Documentation