How to convert NSData to a C struct and use it in Swift program

Question

the data should be binary data, it came from a 360 camera with bluetooth or wifi link ,it will call the function when data is prepared

//ins_gyro_info binary @property (nullable, nonatomic, strong) NSData *gyroData;

struct ins_gyro_info {   
    int64_t timestamp;   //millisecond   
    double gravity_x;   
    double gravity_y;   
    double gravity_z;   
    double rotation_x;   
    double rotation_y;   
    double rotation_z; 
};

- (void)rawDataOutput:(INSCameraRawDataOutput *)rawDataOutput didOutputGyro:(NSData *)gyroData timestamp:(int64_t)timestamp;

and I wanna use this gyro info in my Swift program, the function in Swift like below

func rawDataOutput(_ rawDataOutput: INSCameraRawDataOutput, didOutputGyro gyroData: Data, timestamp: Int64)

I am hard to try stuff the data into ins_gyro_info