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/*
 * Karl Palsson <karlp@tweak.net.au>
 * Considered to be released under your choice of:
 * MIT/ISC/Apache2/BSD2Clause/GPLv2
 * If you're looking for elegant compact performance you've come to the wrong
 * place hombre.
 */

#pragma once

#ifdef	__cplusplus
extern "C" {
#endif

#include <stdbool.h>
#include <stdint.h>

struct ringb {
	volatile unsigned int idx_r;
	volatile unsigned int idx_w;
	uint8_t *buf;
	int buf_len;
};

/**
 * Load up a ring buffer. Always suceeds
 * @param ring struct saving state, provided by the user
 * @param buf where the data will be kept
 * @param len size of buf in in elements.
 */
void ringb_init(struct ringb *ring, uint8_t *buf, int len);

/**
 * push data in
 * @param ring
 * @param c
 * @return true if space was available
 */
bool ringb_put(struct ringb *ring, uint8_t c);

/**
 * pull data out
 * @param ring
 * @return -1 for no data, uint8_t range for valid.
 */
int ringb_get(struct ringb *ring);

/**
 * Toss data and reset to empty
 * @param ring
 */
void ringb_flush(struct ringb *ring);

int ringb_depth(struct ringb *ring);



#ifdef	__cplusplus
}
#endif