ring_buffer.c

#define BUF_SIZE 8

typedef struct {
    int buffer[BUF_SIZE];
    int head;   // write index
    int tail;   // read index
} RingBuffer;

void init_buffer(RingBuffer *rb){
    rb->head = 0;
    rb->tail = 0;
}

int  is_empty(RingBuffer *rb){
    return rb->head == rb->tail;
}

int  is_full(RingBuffer *rb){
    return (((rb->head + 1) % BUF_SIZE) == rb->tail);
}

int  enqueue(RingBuffer *rb, int data){
    if(is_full(rb))
        return 0;
    
    rb->buffer[rb->head] = data;
    rb->head = (rb->head + 1) % BUF_SIZE;
    return 1;
}

int  dequeue(RingBuffer *rb, int *data){
    if(is_empty(rb))
        return 0;
    
    *data = rb->buffer[rb->tail];
    rb->tail = (rb->tail + 1) % BUF_SIZE;
    return 1;
}