Ringbuffer implementation, tailored for logging. More...

#include <stdio.h>
#include <string.h>
#include <osmocom/core/strrb.h>
#include <osmocom/core/talloc.h>

Functions
struct osmo_strrb *	osmo_strrb_create (void *talloc_ctx, size_t rb_size)
	Create an empty, initialized osmo_strrb. More...

bool	osmo_strrb_is_empty (const struct osmo_strrb *rb)
	Check if an osmo_strrb is empty. More...

const char *	osmo_strrb_get_nth (const struct osmo_strrb *rb, unsigned int string_index)
	Return a pointer to the Nth string in the osmo_strrb. More...

bool	_osmo_strrb_is_bufindex_valid (const struct osmo_strrb *rb, unsigned int bufi)

size_t	osmo_strrb_elements (const struct osmo_strrb *rb)
	Count the number of log messages in an osmo_strrb. More...

int	osmo_strrb_add (struct osmo_strrb rb, const char data)
	Add a string to the osmo_strrb. More...

Detailed Description

Ringbuffer implementation, tailored for logging.

This is a lossy ringbuffer. It keeps up to N of the newest messages, overwriting the oldest as newer ones come in.

Ringbuffer assumptions, invarients, and notes:

start is the index of the first used index slot in the ring buffer.
end is the index of the next index slot in the ring buffer.
start == end => buffer is empty
Consequence: the buffer can hold at most size - 1 messages (if this were not the case, full and empty buffers would be indistinguishable given the conventions in this implementation).
Whenever the ringbuffer is full, start is advanced. The second oldest message becomes unreachable by valid indexes (end is not a valid index) and the oldest message is overwritten (if there was a message there, which is the case unless this is the first time the ringbuffer becomes full).

Functions