gr::buffer_reader Class Reference

How we keep track of the readers of a gr::buffer. More...

#include <gnuradio/buffer_reader.h>

Public Member Functions
virtual	~buffer_reader ()
void	declare_sample_delay (unsigned delay)
unsigned	sample_delay () const
virtual int	items_available () const
	Return number of items available for reading. More...
buffer_sptr	buffer () const
	Return buffer this reader reads from. More...
int	max_possible_items_available () const
	Return maximum number of items that could ever be available for reading. This is used as a sanity check in the scheduler to avoid looping forever. More...
const void *	read_pointer ()
	return pointer to read buffer. More...
void	update_read_pointer (int nitems)
void	set_done (bool done)
bool	done () const
gr::thread::mutex *	mutex ()
uint64_t	nitems_read () const
void	reset_nitem_counter ()
size_t	get_sizeof_item ()
block_sptr	link () const
	Return the block that reads via this reader. More...
void	get_tags_in_range (std::vector< tag_t > &v, uint64_t abs_start, uint64_t abs_end, long id)
	Given a [start,end), returns a vector all tags in the range. More...
virtual bool	input_blkd_cb_ready (int items_required) const
	Returns true when the current thread is ready to call the callback, false otherwise. Delegate calls to buffer class's input_blkd_cb_ready(). Note if input_blocked_callback is overridden then this function should also be overridden. More...
virtual bool	input_blocked_callback (int items_required, int items_avail)
	Callback function that the scheduler will call when it determines that the input is blocked. Delegate calls to buffer class's input_blocked_callback(). Override this function if needed. More...
unsigned int	get_read_index () const
uint64_t	get_abs_read_offset () const

Protected Member Functions
	buffer_reader (buffer_sptr buffer, unsigned int read_index, block_sptr link)
	constructor is private. Use gr::buffer::add_reader to create instances More...

Protected Attributes
buffer_sptr	d_buffer
unsigned int	d_read_index
uint64_t	d_abs_read_offset
std::weak_ptr< block >	d_link
unsigned	d_attr_delay

Friends
class	buffer
class	buffer_double_mapped
class	buffer_single_mapped
class	buffer_reader_sm
GR_RUNTIME_API buffer_reader_sptr	buffer_add_reader (buffer_sptr buf, int nzero_preload, block_sptr link, int delay)
	Create a new gr::buffer_reader and attach it to buffer buf. More...

Detailed Description

How we keep track of the readers of a gr::buffer.

Constructor & Destructor Documentation

~buffer_reader()

virtual gr::buffer_reader::~buffer_reader ( )

virtual

buffer_reader()

gr::buffer_reader::buffer_reader ( buffer_sptr  buffer, unsigned int  read_index, block_sptr  link  )

protected

constructor is private. Use gr::buffer::add_reader to create instances

Member Function Documentation

buffer()

buffer_sptr gr::buffer_reader::buffer ( ) const

inline

Return buffer this reader reads from.

declare_sample_delay()

void gr::buffer_reader::declare_sample_delay

(

unsigned

delay

)

Declares the sample delay for this reader.

See gr::block::declare_sample_delay for details.

Parameters

delay

The new sample delay

done()

bool gr::buffer_reader::done ( ) const

inline

get_abs_read_offset()

uint64_t gr::buffer_reader::get_abs_read_offset ( ) const

inline

get_read_index()

unsigned int gr::buffer_reader::get_read_index ( ) const

inline

get_sizeof_item()

size_t gr::buffer_reader::get_sizeof_item ( )

inline

get_tags_in_range()

void gr::buffer_reader::get_tags_in_range	(	std::vector< tag_t > &	v,
		uint64_t	abs_start,
		uint64_t	abs_end,
		long	id
	)

Given a [start,end), returns a vector all tags in the range.

Get a vector of tags in given range. Range of counts is from start to end-1.

Tags are tuples of: (item count, source id, key, value)

Parameters

v	a vector reference to return tags into
abs_start	a uint64 count of the start of the range of interest
abs_end	a uint64 count of the end of the range of interest
id	the unique ID of the block to make sure already deleted tags are not returned

input_blkd_cb_ready()

virtual bool gr::buffer_reader::input_blkd_cb_ready ( int  items_required ) const

inlinevirtual

Returns true when the current thread is ready to call the callback, false otherwise. Delegate calls to buffer class's input_blkd_cb_ready(). Note if input_blocked_callback is overridden then this function should also be overridden.

Reimplemented in gr::buffer_reader_sm.

input_blocked_callback()

virtual bool gr::buffer_reader::input_blocked_callback ( int  items_required, int  items_avail  )

inlinevirtual

Callback function that the scheduler will call when it determines that the input is blocked. Delegate calls to buffer class's input_blocked_callback(). Override this function if needed.

Reimplemented in gr::buffer_reader_sm.

items_available()

virtual int gr::buffer_reader::items_available ( ) const

virtual

Return number of items available for reading.

Reimplemented in gr::buffer_reader_sm.

link()

block_sptr gr::buffer_reader::link ( ) const

inline

Return the block that reads via this reader.

max_possible_items_available()

int gr::buffer_reader::max_possible_items_available ( ) const

inline

Return maximum number of items that could ever be available for reading. This is used as a sanity check in the scheduler to avoid looping forever.

mutex()

gr::thread::mutex * gr::buffer_reader::mutex ( )

inline

nitems_read()

uint64_t gr::buffer_reader::nitems_read ( ) const

inline

read_pointer()

const void * gr::buffer_reader::read_pointer

(

)

return pointer to read buffer.

The return value points to items_available() number of items

reset_nitem_counter()

void gr::buffer_reader::reset_nitem_counter ( )

inline

sample_delay()

unsigned gr::buffer_reader::sample_delay

(

)

const

Gets the sample delay for this reader.

See gr::block::sample_delay for details.

set_done()

void gr::buffer_reader::set_done ( bool  done )

inline

update_read_pointer()

void gr::buffer_reader::update_read_pointer

(

int

nitems

)

Friends And Related Function Documentation

buffer

friend class buffer

friend

buffer_add_reader

GR_RUNTIME_API buffer_reader_sptr buffer_add_reader ( buffer_sptr  buf, int  nzero_preload, block_sptr  link, int  delay  )

friend

Create a new gr::buffer_reader and attach it to buffer buf.

Parameters

buf	is the buffer the gr::buffer_reader reads from.
nzero_preload	– number of zero items to "preload" into buffer.
link	is the block that reads from the buffer using this gr::buffer_reader.
delay	Optional setting to declare the buffer's sample delay.

buffer_double_mapped

friend class buffer_double_mapped

friend

buffer_reader_sm

friend class buffer_reader_sm

friend

buffer_single_mapped

friend class buffer_single_mapped

friend

Member Data Documentation

d_abs_read_offset

uint64_t gr::buffer_reader::d_abs_read_offset

protected

d_attr_delay

unsigned gr::buffer_reader::d_attr_delay

protected

d_buffer

buffer_sptr gr::buffer_reader::d_buffer

protected

d_link

std::weak_ptr<block> gr::buffer_reader::d_link

protected

d_read_index

unsigned int gr::buffer_reader::d_read_index

protected

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

• buffer_reader.h