# An explorative peek into generating deterministic primes through a multi-level multi-language tunneling apparatus

, 2 Apr 2010 CPOL
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This paper is a summary of a research exercise conducted in conjunction by Nish Sivakumar, Professor Cuthbert Calculus, and Glenn Quagmire.

This article was written as a joke for April Fools Day 2010. Readers are advised not to take the contents of this article too seriously.

## Introduction

This paper is a summary of a research exercise conducted in conjunction by Nish Sivakumar, Professor Cuthbert Calculus, and Glenn Quagmire. The paper describes an explorative peek into generating deterministic primes through a multi-level multi-language tunneling apparatus. The example code is kept simple enough so as to keep focus on the fundamental problem we are attempting to solve. At the core, we start off with an inline assembler method consumed by an exported C function, wrapped and exported as a C++ class that's then consumed and exposed to the CLR through a C++/CLI wrapper, which is then used by a C# COM DLL that exposes an interface that is consumed through VBScript and executed through a command scriplet.

## Inline assembly

```int GenerateIndex(int num)
{
_asm
{
mov eax, dword ptr [num]
xor edx, edx
mov ecx, 3
idiv ecx
mov eax, edx
}```

This is the core randomization code and it's in assembly to keep things simple and lightweight. In the example we restrict the number of cached prime numbers to 3 and hence the divisor in the code.

## C DLL Export

```int __stdcall DllMain()
{
return 0;
}

int primes[] = { 29, 37, 61 };

__declspec(dllexport) int GetDetPrime()
{
return primes[GenerateIndex(GetTickCount())];
}```

The C DLL essentially exports a simple function that returns a deterministic prime, and the code internally delegates the randomization logic to the assembler code. At this point the library is consumable by any framework or layer capable of calling a C DLL.

## C++ class Export

```// The header file
class __declspec(dllexport) CDetPrimeLib
{
public:
int GetDetPrime();
};

// Implementation file
#pragma comment(lib, "DetPrime.lib")

extern "C" __declspec(dllimport) int GetDetPrime();

int CDetPrimeLib::GetDetPrime()
{
return ::GetDetPrime();
}```

Here we wrap the C DLL and export it as a C++ class to natively support the most popular programming language in the world. It's a very thin wrapper since we don't want to add any overhead at this point.

## CLI wrapper using C++/CLI

```#pragma once

#pragma comment(lib, "DetPrimeLib.lib")

class __declspec(dllimport) CDetPrimeLib
{
public:
int GetDetPrime();
};

namespace DetPrimeManWrap
{
public ref class DetPrimeManaged
{
CDetPrimeLib* pNative;

public:
DetPrimeManaged()
{
pNative = new CDetPrimeLib();
}

~DetPrimeManaged()
{
this->!DetPrimeManaged();
}

!DetPrimeManaged()
{
delete pNative;
}

int GetDetPrime()
{
return pNative->GetDetPrime();
}
};
}```

While we have already provided enough API exposure to be considered mainstream, it makes good sense to also directly support .NET and thus we have a C++/CLI wrapper library that exposes the functionality to managed callers.

## COM wrapper using C#

```[assembly: ComVisible(true)]
[assembly: Guid("6b4bf847-a45d-4f87-ba53-0d4a9fffa975")]
[assembly: AssemblyVersion("1.0.1.1")]
[assembly: AssemblyFileVersion("1.0.1.1")]

namespace DetPrimeCOM
{
using DetPrimeManWrap;

[Guid("18535B5E-0561-4BA8-8CF6-85B148F3A4CF")]
[ComVisible(true)]
[InterfaceType(ComInterfaceType.InterfaceIsDual)]
public interface IDetPrime
{
int GetDetPrime();
}

[Guid("2299461C-1FFB-4D5D-A521-0830F93FB5CC")]
[ComVisible(true)]
[ClassInterface(ClassInterfaceType.AutoDual)]
public class DetPrime : IDetPrime
{
public int GetDetPrime()
{
return new DetPrimeManaged().GetDetPrime();
}
}
}```

Since we support .NET we may as well support COM too and that's what the above C# code does. The code is now ready for COM consumption.

## VBScript caller

```Dim detPrime
Set detPrime = CreateObject("DetPrimeCOM.DetPrime")
Wscript.Echo "The generated Deterministic Prime is " & detPrime.GetDetPrime```

VB6 is now officially extinct and so we resort to a simple VBScript script to invoke the COM library.

## Command scriplet

`@%windir%\syswow64\cscript.exe /nologo DetPrime.vbs`

And the last piece in our architecture is the command scriplet which executes the VBScript through cscript.exe so we can run it on a 64 bit OS, even though the code is 32 bit to support the vast majority of frameworks out there.

## Conclusion

This article was written as a joke for April Fools Day 2010. Readers are advised not to take the contents of this article too seriously.

## About the Authors

United States
Nish is a real nice guy who has been writing code since 1990 when he first got his hands on an 8088 with 640 KB RAM. Originally from sunny Trivandrum in India, he has been living in various places over the past few years and often thinks it’s time he settled down somewhere.

Nish has been a Microsoft Visual C++ MVP since October, 2002 - awfully nice of Microsoft, he thinks. He maintains an MVP tips and tricks web site - www.voidnish.com where you can find a consolidated list of his articles, writings and ideas on VC++, MFC, .NET and C++/CLI. Oh, and you might want to check out his blog on C++/CLI, MFC, .NET and a lot of other stuff - blog.voidnish.com.

Nish loves reading Science Fiction, P G Wodehouse and Agatha Christie, and also fancies himself to be a decent writer of sorts. He has authored a romantic comedy Summer Love and Some more Cricket as well as a programming book – Extending MFC applications with the .NET Framework.

Nish's latest book C++/CLI in Action published by Manning Publications is now available for purchase. You can read more about the book on his blog.

Despite his wife's attempts to get him into cooking, his best effort so far has been a badly done omelette. Some day, he hopes to be a good cook, and to cook a tasty dinner for his wife.

Architect
United States
I am a multiple PhD with a deep interest in science. My recent research has been in the field of deterministic prime numbers.

Program Manager
United States
I am a former airline pilot who's currently doing research on deterministic primes under Professor Calculus.

## Comments and Discussions

 First PrevNext
 My Vote of 5 thatraja 31-Mar-14 21:56
 Re: My Vote of 5 Nish Sivakumar 2-Apr-14 5:06
 My vote of 5 gndnet 7-Nov-12 8:44
 My Vote of 5 thatraja 1-Apr-11 6:44
 Re: My Vote of 5 Nishant Sivakumar 1-Apr-11 10:29
 Excellent article thatraja 14-Jan-11 4:40
 Re: Excellent article Nishant Sivakumar 14-Jan-11 4:53
 Never tell the same joke twice pwasser 22-Dec-10 17:25
 Whoa Andy Brummer 2-Apr-10 6:13
 Re: Whoa Nishant Sivakumar 2-Apr-10 6:22
 Re: Whoa Pete O'Hanlon 2-Apr-10 10:09
 I've had more time to review your code, and I can determine that you had no budget for 1s either. I assume you were left with only 0s. Think how much faster the computation will be when you get the funding to put the missing 1s in place. "WPF has many lovers. It's a veritable porn star!" - Josh SmithAs Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.
 Plzzzz Help Abhinav S 2-Apr-10 5:45
 Re: Plzzzz Help Nishant Sivakumar 2-Apr-10 5:46
 Re: Plzzzz Help Abhinav S 2-Apr-10 6:16
 Nice - but impressive ! emilio_grv 1-Apr-10 22:22
 Re: Nice - but impressive ! Nishant Sivakumar 2-Apr-10 3:02
 This could lead to man love. Pete O'Hanlon 1-Apr-10 10:27
 Re: This could lead to man love. Nishant Sivakumar 1-Apr-10 13:34
 Excellent Douglas Troy 1-Apr-10 10:16
 Re: Excellent Nishant Sivakumar 1-Apr-10 13:34
 Memory hog... Mike Rich 1-Apr-10 9:37
 Re: Memory hog... Nishant Sivakumar 1-Apr-10 13:33
 Brilliant stuff! Ravi Bhavnani 1-Apr-10 8:32
 Re: Brilliant stuff! Nishant Sivakumar 1-Apr-10 13:33
 My vote of 1 sam.hill 1-Apr-10 5:54
 Last Visit: 31-Dec-99 19:00     Last Update: 28-Dec-14 10:52 Refresh 12 Next »

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