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#ifndef RING_BUFFER_H
#define RING_BUFFER_H
/*--------------------------------------------------------------------
* Ring buffer to store scan codes from keyboard
*------------------------------------------------------------------*/
#ifndef RBUF_SIZE
# define RBUF_SIZE 32
#endif
#include <util/atomic.h>
#include <stdint.h>
#include <stdbool.h>
static uint8_t rbuf[RBUF_SIZE];
static uint8_t rbuf_head = 0;
static uint8_t rbuf_tail = 0;
static inline bool rbuf_enqueue(uint8_t data) {
bool ret = false;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
if (next != rbuf_tail) {
rbuf[rbuf_head] = data;
rbuf_head = next;
ret = true;
}
}
return ret;
}
static inline uint8_t rbuf_dequeue(void) {
uint8_t val = 0;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
if (rbuf_head != rbuf_tail) {
val = rbuf[rbuf_tail];
rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
}
}
return val;
}
static inline bool rbuf_has_data(void) {
bool has_data;
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { has_data = (rbuf_head != rbuf_tail); }
return has_data;
}
static inline void rbuf_clear(void) {
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { rbuf_head = rbuf_tail = 0; }
}
#endif /* RING_BUFFER_H */
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