Validate Configuration Register Layout

Code

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

typedef struct {
    unsigned short reg;
} ConfigRegister;

typedef union {
    struct{
        uint8_t Enable       : 1;
        uint8_t Priority     : 2;
        uint8_t Mode         : 1;
        short Reserved       : 12;
    }raw_bits;
        short raw;
} ConfigRegister_bits;

int validate_config(ConfigRegister *cfg) {
    // Write logic using pointer access
    ConfigRegister_bits ctrl_raw;

    ctrl_raw.raw = cfg->reg;    //access the config reg value in to the union to validate the bit positions

    if((ctrl_raw.raw_bits.Enable == 0) 
        || (ctrl_raw.raw_bits.Priority == 3) 
            || (ctrl_raw.raw_bits.Reserved != 0))
            {
                return 0;
            }
    else
    {
        return 1;
    }
}

int main() {
    ConfigRegister cfg;
    scanf("%hx", &cfg.reg);

    int result = validate_config(&cfg);
    printf("%d", result);

    return 0;
}

Solving Approach