Buffer of simple structures that becomes file backed if it grows beyond a certain size. More...

#include <structbuf.h>

Public Member Functions
size_t	size () const
	Get the number of structures that have been added to the buffer so far.

bool	is_file_backed () const
	Return true if the buffer has become file-backed.

void	append (const T &val)
	Append an item to the buffer.

void	ready_to_read ()
	Stop appending and get ready to read back the data.

const T &	operator[] (size_t idx) const
	Read back an item.

Protected Attributes
T *	membuf = nullptr
	In-memory buffer using during appending.

unsigned	membuf_last = 0
	Number of items in membuf.

const T *	readbuf = (const T*)MAP_FAILED
	Memory area used for reading.

size_t	m_count = 0
	Number of items appended so far.

int	tmpfile_fd = -1
	Unix file descriptor to the temporary file, or -1 if we are memory backed.

Detailed Description

template<typename T, int bufsize = 1024>
class dballe::Structbuf< T, bufsize >

Buffer of simple structures that becomes file backed if it grows beyond a certain size.

bufsize is the number of T items that we keep in memory before becoming file-backed.

Member Data Documentation

template<typename T, int bufsize = 1024>

T* dballe::Structbuf< T, bufsize >::membuf = nullptr

protected

In-memory buffer using during appending.

When it becomes full, it is flushed out to a temporary file.

template<typename T, int bufsize = 1024>

const T* dballe::Structbuf< T, bufsize >::readbuf = (const T*)MAP_FAILED

protected

Memory area used for reading.

It points to membuf if we are memory-backed, or it is the mmap view of the file if we are file-backed

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