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#ifndef RBUFFER_H
#define RBUFFER_H
#include <stddef.h>
#define EEMPTY -1
#define EFULL -2
typedef char rbuffer_byte_t;
struct rbuffer_t {
rbuffer_byte_t* address;
size_t size;
size_t head;
size_t tail;
};
#define RBUFFER_INIT(array, length) \
{ \
.address = array, \
.size = length, \
.head=0, \
.tail=0 \
}
void rbuffer_init(struct rbuffer_t* rb, rbuffer_byte_t* address, size_t size);
/** Read data from ringbuffer. */
static inline int rbuffer_read(struct rbuffer_t* const rb, rbuffer_byte_t* const data_out) {
if (rb->head == rb->tail) return EEMPTY;
*data_out = rb->address[rb->head];
rb->head = rb->head + 1;
if (rb->head >= rb->size) rb->head=0;
return 0;
}
static inline int rbuffer_write(struct rbuffer_t* const rb, rbuffer_byte_t data_in) {
size_t next_tail = rb->tail + 1;
if (next_tail >= rb->size) next_tail = 0;
if (rb->head == next_tail) return EFULL;
rb->address[rb->tail] = data_in;
rb->tail = next_tail;
return 0;
}
#endif
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