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#ifndef RING_BUFFER_H
#define RING_BUFFER_H
/*--------------------------------------------------------------------
* Ring buffer to store scan codes from keyboard
*------------------------------------------------------------------*/
#define RBUF_SIZE 32
static uint8_t rbuf[RBUF_SIZE];
static uint8_t rbuf_head = 0;
static uint8_t rbuf_tail = 0;
static inline void rbuf_enqueue(uint8_t data)
{
uint8_t sreg = SREG;
cli();
uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
if (next != rbuf_tail) {
rbuf[rbuf_head] = data;
rbuf_head = next;
} else {
print("rbuf: full\n");
}
SREG = sreg;
}
static inline uint8_t rbuf_dequeue(void)
{
uint8_t val = 0;
uint8_t sreg = SREG;
cli();
if (rbuf_head != rbuf_tail) {
val = rbuf[rbuf_tail];
rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
}
SREG = sreg;
return val;
}
static inline bool rbuf_has_data(void)
{
uint8_t sreg = SREG;
cli();
bool has_data = (rbuf_head != rbuf_tail);
SREG = sreg;
return has_data;
}
static inline void rbuf_clear(void)
{
uint8_t sreg = SREG;
cli();
rbuf_head = rbuf_tail = 0;
SREG = sreg;
}
#endif /* RING_BUFFER_H */
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