Construct UART Data Frame with Parity Bit

Code

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

typedef struct {
    uint8_t parity_enable : 1;
    uint8_t parity_type   : 1;
    uint8_t reserved      : 6;
} UART_Control;

int countSetBits(unsigned int n) {
    //Write your code here
    int ctr;
    for (int i=0; i < ((sizeof(int)*8)) ; i++) if (n & (1 << i)) ctr++;
    return ctr;
}

uint8_t create_uart_frame(uint8_t data, UART_Control *ctrl) {
    // Your logic here
    int ones;
    if (ctrl->parity_enable == 0)
        return data;
    else{
        ones = countSetBits (data);
        if (ctrl->parity_type == 0 && ((ones % 2) == 1) )
            data |= (1<<7);
        else if (ctrl->parity_type == 1 && ((ones % 2) == 0) )
            data |= (1<<7);
        return data;
    }
    return 0;
}

int main() {
    uint8_t data;
    scanf("%hhu", &data);  // 7-bit input

    uint8_t parity_enable, parity_type;
    scanf("%hhu %hhu", &parity_enable, &parity_type);

    UART_Control ctrl;
    ctrl.parity_enable = parity_enable;
    ctrl.parity_type = parity_type;

    uint8_t frame = create_uart_frame(data, &ctrl);
    printf("frame = 0x%02X", frame);

    return 0;
}

Solving Approach