DynaLib-Extraction - A Dynamic Library Extraction Tool for RAT

RAT takes a dynamic library which contains user's custom function and extracts the function from the library so that it can be used in RAT and perhaps dynamically load a function from the library.

You must be either of the following to use this tool:

A user who wants to create a dynamic lib from a C++ source code.
A user who wants to create a dynamic lib from a MATLAB source code.

Note : Loading a function from a dynamic lib that was created with Matlab source code is not yet supported by RAT.

Inorder to make it easy for the users to create a DLL/.so, this repository has been created

Requirements:

As a basic requirement, user must have CMake installed on their machine. Download CMake from here

Windows Users

Windows 10 or higher
Visual Studio C++ compiler
CMake. Download CMake from here
Dylib.hpp. This is a header file that lets us export our functions. Download it from here or you can find it in the repository.

Unix Users

GCC compiler or Clang compiler
CMake. Download CMake from here
Dylib.hpp. This is a header file that lets us export our functions. Download it from here or you can find it in the repository.

How to Use:

Extracting a function from a dynamic library made with C++

The following example shows how to use the tool.

Download the repository and open C++_DLL_extraction folder.
For the example, main.cpp is used. This should user's custom model function. This is the file that will contain a function that will be extracted and used in RAT.

NOTE: Make sure you put "DYLIB_API" infront of the function you want to export or use (see example). It enables a function to be exported.

The example main.cpp should look like this:

// C++ file that uses the dylib class:
// Include Files
#include <iostream>
#include "dylib.hpp"

DYLIB_API void print_hello()
{
    std::cout << "Hello" << std::endl;
}

// function to print n even numbers
DYLIB_API void print_even(int n)
{
    for (int i = 0; i < n; i++)
    {
        if (i % 2 == 0)
            std::cout << i << std::endl;
    }
}

DYLIB_API int main(){

    std::cout << "Printing 9 even numbers" << std::endl;
    int n = 9;
    print_even(n);
    return 0;
}

Create a dynamic library from the main.cpp file. This is done by using CMake. A template has been made to make it easy. The template is called CMakeLists.txt.

NOTE: It is important that you name CMakeLists.txt as CMakeLists.txt. This is because CMake looks for CMakeLists.txt when it is run.

CMakeLists.txt should look like this:

cmake_minimum_required(VERSION 3.14)
project(matlab_loader CXX)

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR})

if(MSVC)
    set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS TRUE)
endif()
#[replace main.cpp with ur custom file but for example, it is fine to use main.cpp]
#[matlab_lib.dll is generated]
add_library(matlab_lib SHARED main.cpp) 
set_target_properties(matlab_lib PROPERTIES PREFIX "")

Now that we have CMakeLists.txt and main.cpp setup, we can run CMake commands to generate the dynamic library.

Open terminal and navigate to the directory where you have the CMakeLists.txt file and it is suggested for users unfamiliar with CMake to place CMakeLists.txt in the same directory as main.cpp.

Run the following command to make a build folder in current directory:

cmake . -B build

Now, you should see a build folder in the current directory if everything went well.

Then, run the following command to generate the dynamic library.

cmake --build build

Now, you should see a matlab_lib.dll (or matlab_lib.so depending on the OS) in the build/Debug folder.

    Directory of C:\Users\C++_DLL_extraction\build\Debug

02/03/2022  17:02    <DIR>          .
02/03/2022  17:02    <DIR>          ..
02/03/2022  17:02            69,632 matlab_lib.dll
02/03/2022  17:02            12,257 matlab_lib.exp
02/03/2022  17:02            20,736 matlab_lib.lib
02/03/2022  17:02           987,136 matlab_lib.pdb

Thats it! Now, you can input the dynamic library into RAT and use the function.

Extracting a function from a dynamic library made with MATLAB

NOTE: This is not yet supported.

Currently, the only way to extract a function from a dynamic library made with MATLAB is to use the MATLAB Coder/Libray compiler but there seems to be some issues with function names.

Current workflow is Matlab code - > C++ code - > dynamic library - > RAT.

sethupavan12 / DynaLib-Extraction