gr::buffer Class Reference

Single writer, multiple reader fifo. More...

#include <buffer.h>

List of all members.

Public Member Functions
virtual	~buffer ()
int	space_available ()
	return number of items worth of space available for writing
int	bufsize () const
	return size of this buffer in items
void *	write_pointer ()
	return pointer to write buffer.
void	update_write_pointer (int nitems)
	tell buffer that we wrote nitems into it
void	set_done (bool done)
bool	done () const
block_sptr	link ()
	Return the block that writes to this buffer.
size_t	nreaders () const
buffer_reader *	reader (size_t index)
gr::thread::mutex *	mutex ()
uint64_t	nitems_written ()
size_t	get_sizeof_item ()
void	add_item_tag (const tag_t &tag)
	Adds a new tag to the buffer.
void	remove_item_tag (const tag_t &tag, long id)
	Removes an existing tag from the buffer.
void	prune_tags (uint64_t max_time)
	Removes all tags before max_time from buffer.
std::deque< tag_t >::iterator	get_tags_begin ()
std::deque< tag_t >::iterator	get_tags_end ()
Protected Attributes
char *	d_base
unsigned int	d_bufsize
Friends
class	buffer_reader
GR_RUNTIME_API buffer_sptr	make_buffer (int nitems, size_t sizeof_item, block_sptr link)
	Allocate a buffer that holds at least nitems of size sizeof_item.
GR_RUNTIME_API buffer_reader_sptr	buffer_add_reader (buffer_sptr buf, int nzero_preload, block_sptr link)
	Create a new gr::buffer_reader and attach it to buffer buf.

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Detailed Description

Single writer, multiple reader fifo.

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Constructor & Destructor Documentation

virtual gr::buffer::~buffer

(

)

[virtual]

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Member Function Documentation

void gr::buffer::add_item_tag

(

const tag_t &

tag

)

Adds a new tag to the buffer.

Parameters:

tag	the new tag

int gr::buffer::bufsize

(

)

const [inline]

return size of this buffer in items

bool gr::buffer::done

(

)

const [inline]

size_t gr::buffer::get_sizeof_item

(

)

[inline]

std::deque<tag_t>::iterator gr::buffer::get_tags_begin

(

)

[inline]

std::deque<tag_t>::iterator gr::buffer::get_tags_end

(

)

[inline]

block_sptr gr::buffer::link

(

)

[inline]

Return the block that writes to this buffer.

gr::thread::mutex* gr::buffer::mutex

(

)

[inline]

uint64_t gr::buffer::nitems_written

(

)

[inline]

size_t gr::buffer::nreaders

(

)

const [inline]

void gr::buffer::prune_tags

(

uint64_t

max_time

)

Removes all tags before max_time from buffer.

Parameters:

max_time

the time (item number) to trim up until.

buffer_reader* gr::buffer::reader

(

size_t

index

)

[inline]

void gr::buffer::remove_item_tag	(	const tag_t &	tag,
		long	id
	)

Removes an existing tag from the buffer.

If no such tag is found, does nothing. Note: Doesn't actually physically delete the tag, but marks it as deleted. For the user, this has the same effect: Any subsequent calls to get_tags_in_range() will not return the tag.

Parameters:

tag	the tag that needs to be removed
id	the unique ID of the block calling this function

void gr::buffer::set_done

(

bool

done

)

int gr::buffer::space_available

(

)

return number of items worth of space available for writing

void gr::buffer::update_write_pointer

(

int

nitems

)

tell buffer that we wrote nitems into it

void* gr::buffer::write_pointer

(

)

return pointer to write buffer.

The return value points at space that can hold at least space_available() items.

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Friends And Related Function Documentation

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

friend class buffer_reader [friend]

GR_RUNTIME_API buffer_sptr make_buffer	(	int	nitems,
		size_t	sizeof_item,
		block_sptr	link
	)		[friend]

Allocate a buffer that holds at least nitems of size sizeof_item.

The total size of the buffer will be rounded up to a system dependent boundary. This is typically the system page size, but under MS windows is 64KB.

Parameters:

nitems	is the minimum number of items the buffer will hold.
sizeof_item	is the size of an item in bytes.
link	is the block that writes to this buffer.

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Member Data Documentation

char* gr::buffer::d_base [protected]

unsigned int gr::buffer::d_bufsize [protected]

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

• buffer.h