Circular Buffer Read

Code

#include <stdio.h>

typedef struct {
    int buffer[10];
    int head;
    int tail;
    int count;
    int capacity;
} CircularBuffer;

void read_bytes(CircularBuffer *cb, int n) {
    if (!cb) return; 
    
    int to_read = n < cb->count ? n : cb->count; 
    int print_null = n - cb->count;

    for (int i = 0; i < to_read; i++)
    {
        printf("%d", cb->buffer[cb->tail]);
        if (i < to_read - 1) printf(" ");
        cb->tail = (cb->tail + 1) % cb->capacity;
        cb->count--; 
    }
    
    for (int i = 0; i < print_null; i++)
    {
        if (i == 0) printf(" ");
        printf("%s", "NULL");
        if (i < print_null - 1) printf(" ");
    }

    printf("\nTail: %d\n", cb->tail);

}

int main() {
    CircularBuffer cb = {
        .buffer = {10, 20, 30, 40, 50, 60, 70, 80, 90, 100},
        .head = 3,
        .tail = 7,
        .count = 6,
        .capacity = 10
    };

    int n;
    scanf("%d", &n);
    read_bytes(&cb, n);

    return 0;
}

Solving Approach