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;

uint8_t create_uart_frame(uint8_t data, UART_Control *ctrl) {
    uint8_t count = 0;
    uint8_t temp = data;
    uint8_t even_odd = 0; 

    if(ctrl->parity_enable){    // if parity enable.
        
        // count the bits that are set in data.
        while(temp){
            temp &= (temp - 1);
            count++;
        }

        // check if the count is even or odd.
        even_odd = count % 2;
        
        if(even_odd == 0 && ctrl->parity_type == 0){
            return data;
        }
        else if(even_odd == 0 && ctrl->parity_type == 1){
            return 0x80 | data; 
        }
        else if(even_odd == 1 && ctrl->parity_type == 1){
            return data; 
        }
        else if(even_odd == 1 && ctrl->parity_type == 0){
            return 0x80 | data; 
        }
    }
    else{
        return data;
    }
}

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