[Swift vs C] Basic variables interaction

When you interact with Swift and C codes, you will be often confronted with some issues to convert variables.
You have to cast those variables to send/received from/to C, swift in a propper way.

here I simply introduce how to convert variables between Swift and C.
The example codes for C are often written as functions and return variables that may be received by swift.

int type

int of C

C

void NormalInt(int a)
{
    a = 100;
    
    return a;
}

swift

var insertValue:Int = 100

var SwiftValue:Int = Int(NormalInt(Int32(insertValue:Int)))

In this example, you have to convert int type of C to Int type of Swift and equally insertValue is converted to Int32 type of Swift which corresponds to int type of C

int 16 bit

C

void int16bit(int16_t a)
{
    a = 100;
    
    return a;
}

swift

var insertValue:Int = 100

var SwiftValue:Int = Int(NormalInt(Int16(insertValue:Int)))

int 32 bit

C

void int32bit(int32_t a)
{
    a = 100;
    
    return a;
}

swift

var insertValue:Int = 100

var SwiftValue:Int = Int(NormalInt(Int32(insertValue:Int)))

int 64 bit

C

void int64bit(int64_t a)
{
    a = 100;
    
    return a;
}

swift

var insertValue:Int = 100

var SwiftValue:Int = Int(NormalInt(Int64(insertValue:Int)))

float type

C

float floatfunc(float a)
{
    return a;
}

Swift

var insertFloat:Float = 0.1
var varfloat:Float = floatfunc(insertFloat)

double type

C

float doublefunc(double a)
{
    return a;
}

Swift

var insertDouble:Double = 0.1
var varDouble:Double = doublefunc(insertDouble)

It is not necessary to convert float and double types of C to Float and Double types of Swift.