I have a .dll file which I've decompiled with the software called "Reflector7.4.1" to get the source code. After decompiling, to my surprise, I got a folder instead of a single source code file.The folder contained a bunch of other files and subfolders with files.
I have identified the file in which I have to modify the code.But the problem is,after I have modified the only 1 file, how do I compile the whole bunch of folders and subfolders and many other files that I have not edited-into a single .dll file as they were before?
You should not recompile decompiled code, since the compilation process is not completely reversible, even for .NET binaries. There are many missing libraries you might need, mismatches in libraries, etc. I would suggest decompiling and then patching the DLL using a .NET assembly editor of some sort.
Reflexil is one you should check out.
You should also understand .NET disassembly and understand how to move back and forth from the decompiled source and the binaries, so you'll know exactly what you want to change.
Related
I have compiled Lua 5.3 as a 32 bit c++ DLL and exe. The DLL contains all the lua code except for lua.cpp and luac.cpp. The exe compiles lua.cpp and uses the DLL to run the lua interpreter. This works fine when running on its own from the command line. I wish to be able to run from the IDE using this DLL and exe.
If I replace /ZeroBraneStudio/bin/lua53.dll and lua53.exe with my own versions, I can run scripts (clicking the two green arrows). However, debugging does not work, giving the following error:
The procedure entry point luaL_addlstring could not be located in the dynamic link library lua53.dll.
I can see that this is happening because the debugger is making use of luasocket. \ZeroBraneStudio\bin\clibs53\socket\core.dll is dependent on lua53.dll, and is expecting it to contain lua compiled as c.
So, what is the correct solution to this - is it to compile luasocket as c++ as well?
(And, if so, does anybody have instructions/guidance for doing so? I have been unable to find anything on this.)
Thanks.
I'm not sure how exactly the DLL was compiled, but the error message likely indicates that the luaL_addlstring and other functions are not exported by it. If the symbols are exported correctly, you should be able to load luasocket and get the debugging working. See this thread for the related discussion.
Also, you don't need to replace lua53 library and executable, as you can configure the IDE to use your own copy of it using path.lua53 configuration setting as described in the documentation.
Okay, I was able to get it working. The solution was to compile luasocket as c++. I won't give full instructions on how to do this here, but some points to hopefully help anybody else with the same issue:
Got luasocket from here: https://github.com/diegonehab/luasocket
Renamed all *.c files to *.cpp
Renamed Lua52.props to Lua.props (I am using lua 5.3 but seems like it is compatible?)
Placed lua headers and lib in appropriate folders
Opened solution in Visual Studio 2012
Fixed up minor issues with project files, like the renaming of the files.
Added 'extern "C"' to declaration of luaopen_socket_core and luaopen_mime_core functions (necessary for lua to be able to load libraries).
Built solution
Copied new dlls into clibs53/socket and clibs53/mime folders.
I used Dependency Walker to help with this. If anybody wants further details in the future please leave a comment.
Given the following:
the 32-bit DLL code file of some old Firefox plugin (i.e. a DLL containing among other a Typelib, XSD and XSL entries), without source code or debug info, originally coded in C++ and compiled with Visual Studio,
the name and parameters of an exported function/method in this DLL (a function of the Firefox plugin, accessable in JS code),
Visual Studio Community 2013 running on Windows 7,
experience in C++ development, but not with COM or Firefox,
experience with debugging Intel assembler code,
a code license which does not prohibit disassembling the DLL,
I would like to do this: Load the DLL into some C++ code, and step on CPU level into the code of the function to find out what it exactly does.
Can you give me any hint on where to start and how get this done? I guess the DLL may need some Firefox-specific initialization before I can call the function which I would like to debug. Could this be done with the Firefox SDK, without source code and debug info for the DLL? Or may I succeed in "nakedly" loading the DLL, finding the entry point of the - rather simple - function (how?) and calling it?
Thanks for any hints.
If no pdb file or source code, it is hard for you to debug the dll file, since the debugger loads debugging information from the PDB file and uses it to locate symbols or relate current execution state of a program source code. Visual Studio uses PDB files as its primary file format for debugging information during debugging. If no those files, you couldn't debug that library.
Update:
We are dynamically loading a dll to one project using LoadLibrary() function, but if you want to step into your dll file, it really require the pdb file. A simple sample is that you could create and place one pdb file in the same folder as one simple custom dll library project located. I think Visual Studio will automatically search the directory and load them, you could find the information in your Debug modules windows.
The following case is not the same issue as yours, but it also shared us that it would load the pdb file if the dll file was really called by one project/process:
Does winbase::LoadLibrary() load .pdbs?
When I was going to set up my developing environment for (SDLSimple DirectMediaLayer), I downloaded the package provided by the website, from the readme.txt file I found that I need both .lib and .dll...
My question is :
I am not sure if my understanding is correct : in my thought, .lib for windows is like .a for linux, is static library, and .dll for windows is like .so for linux, is shared library, is this correct ?
If the idea above is correct, I think we can only use .lib or .dll, since the work they do is the same ? So why bother to get both two in one program ?
And I do not quite understand .dll, if my memory servers me right, the one of the advantage for shared library is they can be updated while the program is running, so how can people do this, if we update the .dll file, how can an running program get to know the changes of the .dll and reload it to memory ?
In VC, there are two kinds of libs.
First type is a "real library", generated by the "static library project", which contains everything you can link and run, without dll.
The second type is "import library", generated by the "dll project", which just contains the symbols the link.exe needs. You can link to the library, but you need the dll to run.
There are two ways to use a dll. Link to the "import library" or "use LoadLibrary API".
You can not change the dll file when the dll is loaded.
But if you use LoadLibrary to load the dll, you can use FreeLibrary to unload the dll, change the dll and then use LoadLibrary to load the new dll. Of course, you need to monitor something to invoke this procedure.
Still the easier way is that, use a loader to do the update, then load the real exe.
Is it possible in MSBuild 4.0 and/or 4.5 to specify additional files to be treated as a manifest output of a project by its dependencies, and copied with the binary project output, whenever that is copied? Ideally, I want to create some files beside a .dll during build, and would like these files to stay in the same folder as the .dll whenever it is copied to a directory of a project depending on it.
If this is not clear, I am thinking of .pdb and documentation .xml files created by the C# compiler. These files treated specially: Whenever another project requests the .dll be copied locally into its binary directory, these files go with the .dll. Can I augment this set with my own special files?
This is not possible, and here is why. Actually, there is no concept of project output accessible externally between MSBuild projects. Rather, when a reference to a project is added, the SDK-provided build framework (based on MSBuild scripts) looks for a few specific files matching the name of the referenced DLL, and copies these files with the DLL itself into the current project output directory (assuming CopyLocal is set, which is probably true for a referenced project).
In framework v4.0, this is done by the task ResolveAssemblyReference which is called from an identically named target from the file %windir%\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.targets. The task looks for specially named files placed beside the target DLL, including its matchin PDB files and an XML documentation file. Other files are also discovered, as I infer from the decompiled source.
So nothing in a given project specifically marks these files as somehow "exported" from the project. The magic happens on the pulling side.
i did a build in vb.net and got one exe file
however, when a user runs the file, it says it is missing one of the libraries (itextsharp).
so the question is, if there is actually a build option in vb.net, why does it not include the library in the same exe file?
You can distribute the iTextSharp DLL with your application. The easiest way to do this is to simply include it in the same folder as your EXE. The DLL should be output to your Project's Debug/Release folder each time you build assuming you've added it as a Reference in your project and the Reference's 'Copy Local' property is set to True.
If you want to distribute one EXE and include the iTextSharp in that, you can use the ILMerge tool (or alternately Gilma from SourceForge) after you build your EXE.
in the properties for the reference set the Copy To Output to Always
ITextSharp is not a library linked in your project output; it's an assembly referenced by your project output. And while VB.Net builds one executable from your source code, the CLR still needs all the referenced assemblies in the same folder as your executable.
To make everything work, you can distribute ITextSharp assemblies along with your app. Alternatively, if you indeed need only one file, you can use ILMerge on your project output and the assemblies you want included. However, you might need to determine all the correct assemblies you need merged. I wouldn't revommend using this tool, unless you understand how it works.
Note: If you want to use ILMerge with .Net v4.0, read this page.