Circular Buffer Read

Code

  #include <stdio.h>
#include <stdint.h>

typedef struct{
    int buffer[10];
    int head;    
    int tail;   
    int size;    
    int capacity;    
} Circular_t; 

void create_circular(Circular_t *cb){
    cb->capacity = 10;


    for(int i = 0; i < cb->capacity; i++){
        cb->buffer[i] = (i + 1) * 10;
    }

  
    cb->size = 6;
    cb->tail = 7; 
    cb->head = (cb->tail + cb->size) % cb->capacity;  // (7 + 6) % 10 = 3
}

void read_bytes_Circular(Circular_t *cb, int n){
    if(n <= cb->size){
        for(int i = 0; i < n; i++){
        printf("%d", cb->buffer[cb->tail]);
        if(i < (n - 1)){
          printf(" ");
        }
        cb->tail = (cb->tail + 1) % cb->capacity;
        cb->size--;
    }
    printf("\n");
    printf("Tail: %d",cb->tail);
    }
    else{
      int tmp = cb->size; 
      for(int i = 0; i < tmp; i++){
        printf("%d", cb->buffer[cb->tail]);
          printf(" ");
        cb->tail = (cb->tail + 1) % cb->capacity;
        cb->size--;
    }
    for(int i = 0; i< n - tmp; i++){
      printf("NULL"); 
      if(i< (n- tmp - 1)){
        printf(" ");
      }
    }
    printf("\n");
    printf("Tail: %d",cb->tail);
    }
    
}

int main(void){
    Circular_t cb; 
    create_circular(&cb); 

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

    read_bytes_Circular(&cb, n);
    return 0;
} 

Solving Approach