#include "circbuff.h"

void circbuff_init(circbuff_t* buf) {
    buf->num_entries = 0;
    buf->head = 0;
    buf->tail = 0;
}

bool circbuff_empty(circbuff_t* buf) {
    return (buf->num_entries == 0);
}

bool circbuff_full(circbuff_t* buf) {
    return (buf->num_entries == CIRCBUFF_SIZE);
}

bool circbuff_write(circbuff_t* buf, unsigned char value) {
    if (circbuff_full(buf)) return false;
    buf->buffer[buf->tail] = value;
    buf->num_entries++;
    buf->tail = (unsigned char)(buf->tail + 1) % CIRCBUFF_SIZE;
    return true;
}

bool circbuff_read(circbuff_t* buf, unsigned char* value) {
    if (circbuff_empty(buf)) return false;
    *value = buf->buffer[buf->head];
    buf->num_entries--;
    buf->head = (unsigned char)(buf->head + 1) % CIRCBUFF_SIZE;
    return true;
}