dx::stream::cursor Struct Reference

a client's own place in a ring and the margin it keeps to the transport More...

#include <dx_stream.h>

Public Member Functions
bool	anchor (const circular &circular)
	the position against the transport's index, every cycle: false where the client stands
	operator bool () const
void	unanchor ()

Static Public Member Functions
static uint64_t	bytes (uint32_t ticks, uint32_t interval, uint64_t linesize)
	a safety offset in bytes: ticks of the transport's interval (samples), in lines of the ring's format
template<typename stream_t>
static uint32_t	ticks (const stream_t &stream, direction::direction direction, uint32_t out, uint32_t in, uint32_t block)
	the margin ticks a host answers a client of a stream: behind a transport writer a reader trails the client writers' cycle, which a bidirectional stream alone carries

Public Attributes
bool	anchored {}
uint64_t	block {}
	one cycle's move: a client trails a transport writer by a whole one
uint64_t	margin {}
	the client's safety offset to the transport
uint64_t	position {}
	the client's index into the ring
direction::direction	transport {direction::none}
	the stream's transport: in writes the ring at tx, out reads it at rx

Detailed Description

a client's own place in a ring and the margin it keeps to the transport

The ring's shared indices are the transport's: a transport writer's tx, a transport reader's rx; the other index hangs. A client keeps its own position beside them, anchored to the transport's index by its margin: behind a writer's tx by a whole block more, so its own cycle never reaches the transport's; ahead of a reader's rx. Client writers mix at their positions, tx staying the high-water of all writers; client readers read at theirs and publish nothing. A client moves only as the transport moves: every cycle it checks its position against the transport's index - it stands, without access, where the transport moved no block since, and anchors afresh where it fell behind the transport's reach or at the session's start. Margin and block are bytes in the ring's format, cached out of the tick, the transport the stream's from its desc.

Member Function Documentation

anchor()

bool dx::stream::cursor::anchor ( const circular & circular )

inline

the position against the transport's index, every cycle: false where the client stands

bytes()

uint64_t dx::stream::cursor::bytes ( uint32_t ticks, uint32_t interval, uint64_t linesize )

inlinestatic

a safety offset in bytes: ticks of the transport's interval (samples), in lines of the ring's format

Here is the call graph for this function:

Here is the caller graph for this function:

operator bool()

dx::stream::cursor::operator bool ( ) const

inlineexplicit

ticks()

template<typename stream_t>

uint32_t dx::stream::cursor::ticks ( const stream_t & stream, direction::direction direction, uint32_t out, uint32_t in, uint32_t block )

inlinestatic

the margin ticks a host answers a client of a stream: behind a transport writer a reader trails the client writers' cycle, which a bidirectional stream alone carries

Here is the caller graph for this function:

unanchor()

void dx::stream::cursor::unanchor ( )

inline

Member Data Documentation

anchored

bool dx::stream::cursor::anchored {}

the position is anchored to the transport's index

block

uint64_t dx::stream::cursor::block {}

one cycle's move: a client trails a transport writer by a whole one

margin

uint64_t dx::stream::cursor::margin {}

the client's safety offset to the transport

position

uint64_t dx::stream::cursor::position {}

the client's index into the ring

transport

direction::direction dx::stream::cursor::transport {direction::none}

the stream's transport: in writes the ring at tx, out reads it at rx

---

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

• dx_stream.h