how is the build order of kernel by Wince 6.0 - build

I've changed the file "handle.c" in winceos\COREOS\nk\kernel.. and need to build according to take the changes into the core.dll for nk.bin
is there any build order to follow to avoid to build the hole solution?

First, let me say that making that change where you did is a bad, bad idea. Never change the public or private trees directly. If Microsoft issues a QFE that changes that code, when you apply the QFE, your changes will be overwritten and without warning. Always clone the code and change the clone.
As far as making kernel changes without having to rebuild the entire project, the answer is no, you can't. Changes in the code potentially change addresses, and a vast amount of the OS is fixed up with those addresses during the build process. You'll have to rebuild the entire thing after a change like that (as opposed to, for example, drivers which you can build individually without rebuilding the entire OS).

thanks for your answer.
what I found now by trying myself is yes, it's possible by doing "build & sysgen" of "winceos" folder under PRIVATE.
The change execution on kernel code was just adding a RETAILMSG to see the HANDLE count.
The file handle.c create handle table and give handles. There is a number of commands creating/allocating handle. I do not really know, by which handle requests the kernel calls handle.c(??), but it "can" for some developers be usefull to be able to manuplate it??
But in summary, doing "build & sysgen"+"MakeRunTimeImage" makes the changes on kernel valid.
I did it on "PRIVATE/winceos", but perhaps it's also possible by doing iy more locally, for example on PRIVATE/winceos/COREOS/nk/kernel folder. I didn't tried it ;)

Related

Run own code elevated at will from non-elevated plugin DLL

I am making a suite of 64-bit plugin DLLs for a Windows host application using Visual Studio/C++, and from the current version onward, the setup.exe that they come in creates a single shared user-writable folder under ProgramData in which I cache all sorts of (non-user specific) data files. Older versions didn't have that folder yet.
However, the distribution of my plugin binaries is often out of my hands too. They are repackaged by a 3rd party bundle which can only do dumb file copies of the DLLs (so no real setup.exe functionality I need like creating folder + set permissions). And since my binary DLLs are all 100% self-contained, users also historically have a hand of just copying the DLLs around to other machines as they see fit, but that ofc also lacks the new folder setup phase.
I am looking into a workaround to have my DLLs create the folder at runtime if it is missing. I know I can't elevate the host process in-place whenever I want, but I thought of the following ways:
Have an extra "FixSetup" entry point in my DLL, and when the need arises, start an elevated RunDLL32.exe and let it use this entry point in my DLL.However, I see all sorts of people all over the place talking about RunDLL being as good as deprecated and advising against using it, but then again that was already since Windows XP and it's still with us. I also hear of RunDLL having it's own runtime context which can change with every Windows release (like switching to high-DPI aware when that came available), and that it thus is a 'hostile' environment to run in (read it on Raymond Chan's blog IIRC). Should I really be afraid of using it, or is my use case so simple it can barely break? (no GUI, just a wrapped CreateDirectory call)
Create a small "FixSetup.exe" which just does the folder creation, package it into my DLL's resources, and extract-to-temp + run-elevated it at runtime.While this would bloat my DLLs (depending on how small I can get the .exe), I feel like it's also a more fragile + convoluted solution than 1. above (with file extraction and all; prob. best to sign the utility exe too to keep HIPS / antivirus from acting funny etc?).
Alter my DLLs so that they're actually .exes in disguise which happen to export the host-expected DLL entry points, so that I can call them directly (elevated).I know there are some major caveats here (like conflicts between the C runtime being included in DLL or non-DLL mode, Visual Studio prob. not approving of these shenanigans, etc.), and honestly I already feel I need a shower just after talking about this one. So while theoretically maybe feasible, it is my last resort.
Does anyone have any advise on my uncertainties above? Or maybe an even better suggestion?
EDIT
I've already managed to get option 1. working, and while it works seamlessly there's one drawback I spotted: the UAC prompt (understandably) asks whether the user wants to run RunDLL32.exe, signed by Microsoft. This might confuse/scare people no end (that is: if they even read these prompts...). I'd rather have the UAC prompt asking about MyPluginSetup.exe signed by MyCompany, so now I'm more inclined to go with option 2. instead.

how to append data to an executable and use it inside this application

I want to build an C#/Wpf Packer.
I am using a C++ application which will start the packed/crypted C# application.
Currently I have to build this C++ app everytime I want to release my Main-App.
(C#/Wpf-App is included as external Array of Bytes)
Now I want to build a simple tool to do this work, but I dont want to build the "launcher" all the time!
So my idea is just to modify the launcher.
For that I need a way to modify this executable and I need to be able to use this modified data inside the launcher, like it would be compiled.
I dont want to reserve a static sized array inside the launcher, cause I dont know what could be the biggest data-size.
There are different ways to do that. Unfortunately none of them is straightforward nor standard except one: use a makefile that automatically builds the launcher. IMHO, unless you have special requirements such as building the launcher on a system with no development environment, it is probably the most simple and robust way.
As you explicitely ask for other solutions, I will give 2:
on Windows, you could store the c# app as a resource. Once that's done, you can use a resource editor to change it on the fly or build a custom editor using the WinAPI functions BeginUpdateResource, UpdateResource and EndUpdateResource. You later load the resource with LoadResource in the launcher.
you could make the laucher program know its real size and just seek behind that size and load what follows as the C# app. To build it, you just need to copy the actual C++ executable and whatever you want it to process. The hard part here is that there is no portable way to identify the size or the end of an executable at compile time. You could try a two pass build:
first pass, you set the size to an arbitrary value. You build and look at the real size
second pass, you set the size to what has been observed in first pass. As you only modify a size_t value, the size of the executable should not change. But I strongly urge you to control that size twice. Repeat if it is not the same (it could happen if the compiler was too clever and merged identical constants).
But as I already said, my choice would be to use a makefile to automatically generate the launcher each time the C# app is rebuilt

Emscripten application not executing

When running my asmjs\emscripten application, compiled from C++, it has suddenly started to log: "run() called, but dependencies remain, so not running" to the web console, and nothing more happens.
I've added some cout's at the absolute start of my main, but even they aren't reached.
The application executed successfully before, but suddenly this started to happen and I don't know what change triggered this.
Does anyone know how to debug this?
Update
After removing as much source code as I could, this happens as soon as I #include , even due my main simply consists of a single cout.
Ideally you would have the entire environment when it was running in version control, and build every version since to see where it broke.
You might have your code in version control, but perhaps not Emscripten itself. If you've updated Emscripten, this could lead to differences in behaviour. I would try going back to whatever version you used when it was running. Note that sometimes various cache directories survive an Emscripten version change, and might need to be cleared manually (I forgot which exactly).
The dependencies remaining could mean that you are trying to do something before Emscripten has loaded any other files it needs to, say files requested by --preload-file or --memory-init-file. Note that according to https://kripken.github.io/emscripten-site/docs/getting_started/FAQ.html#faq-when-safe-to-call-compiled-functions you should not try to run any Emscripten functions, until the C++ main function has run. To detect this, you can, for example, call your own Javascript function from main (there are other ways).
The fact this wasn't causing a problem before could have been something that seems quite unrelated: a change or update in the web browser, changing limits of concurrent downloads, or a change in the web server this is running from. You could look in the Network tab in the browser to see if anything leaps out at you as being different or suspicious.
However, as main isn't even reached, then it might not be that. I would try commenting out virtually all of your code, and make it so you have practically nothing but a hello-world program. Perhaps you don't have a correct setting in the Module object, or maybe the request for the memory initialization file is failing (you can check in the Network tab in the browser for that one). If your basic hello world program still isn't working, then you could post again, with its code, in a separate question.
This can also happens when the browser runs out of memory. Unfortunately, the browser's memory handling is not in our control so there isn't much you can do beside reducing your payload. This includes code size, preload content size, etc. Basically anything that can reduce the total memory consumption of your program will help fixing this. Browser vendors are constantly working to improve this, but it's going to take a while still.
I think you haven't given enough information to really know for sure. But it might be for instance that your js suddenly crossed some memory threshold which exceeds what the browser wants to allocate to it. You could try reducing the amount of memory used / streaming some assets instead of preloading them / ship less code / use -Os optimization level?

Versioning executable and modifying it in runtime

What I'm trying to do is to sign my compiled executable's first 32 bytes with a version signature, say "1.2.0" and I need to modify this signature in runtime, keeping in mind that:
this will be done by the executable itself
the executable resides on the client side, meaning no recompilation is possible
using an external file to track the version instead of encoding it in the binary itself is also not an option
the solution has to be platform-independent; I'm aware that Windows/VC allows you to version an executable using a .rc resource, but I'm unaware of an equivalent for Mac (maybe Info.plist?) and Linux
The solution in my head was to write the version signature in the first or last 32 bytes of the binary (which I didn't figure out how to do yet) and then I'll modify those bytes when I need to. Sadly it's not that simple as I'm trying to modify the same binary that I'm executing.
If you know of how I can do this, or of a cleaner/mainstream solution for this problem, I'd be very grateful. FWIW, the application is a patcher/launcher for a game; I chose to encode the version in the patcher itself instead of the game executable as I'd like it to be self-contained and target-independent.
Update: from your helpful answers and comments, I see that messing with the header/footer of the binary is not the way to go. But regarding the write permission for the running users, the game has to be patched one way or another and the game files need to be modified, there's no way to circumvent that: to update the game, you'll need admin privileges.
I would opt for using an external file to hold the signature, and modify that with every update, but I can't see how I can guard against the user spoofing with that file: if they mess up the version numbers, how can I detect which version I'm running?
Update2: Thanks for all your answers and comments, in truth there are 2 ways to do this: either use an external resource to track the version or embed it in the main application's binary itself. I could choose only 1 answer on SO so I did the one I'm going with, although it's not the only one. :-)
Modern Windows versions will not allow you to update an installed program file unless you're running with administrator privileges. I believe all versions of Windows block modifications to a running file altogether; this is why you're forced to reboot after an update. I think you're asking for the impossible.
This is going to be a bit of a challenge, for a number of reasons. First, writing to the first N bytes of the binary is likely to step on the binary file's header information, which is used by the program loader to determine where the code & data segments, etc. are located within the file. This will be different on different platforms (see the ELF format and executable format comparison)--there are a lot of different binary format standards.
Assuming you can overcome that one, you're likely to run afoul of security/antivirus systems if you start modifying a program's code at runtime. I don't believe most current operating systems will allow you to overwrite a currently-running executable. At the very least, they might allow you to do so with elevated permissions--not likely to be present while gaming.
If your application is meant to patch a game, why not embed the version in there while you're at it? You can use a string like #Juliano shows and modify that from the patcher while the game is not running - which should be the case if you're currently patching anyways. :P
Edit: If you're working with Visual Studio, it's really easy to embed such a string in the executable with a #pragma comment, according to this MSDN page:
#pragma comment(user, "Version: 1.4.1")
Since the second argument is a simple string literal, it can be concatenated, and I'd have the version in a simple #define:
// somehwere
#define MY_EXE_VERSION "1.4.1"
// somewhere else
#pragma comment(user, "Version: " MY_EXE_VERSION)
I'll give just some ideas on how to do this.
I think it's not possible to change some arbitrary bytes in the executable without side effects. To overcome this, I would create some string in your source code, like:
char *Version = "Version: AA.BB.CC";
I don't know if this is a rule, but you can look for this string in your binary code (open it in a text editor and you will see). So, you search and change this bytes for your version number in the binary file. Probably, their position will vary each time you compile the application, so this it is possible only if that location is not a problem for you.
Because the file is being used (it's running), you have to launch an external program that would do this. After modifying the file, this external program could relaunch the original application.
The version will be stored in your binary code in some part. Is that useful? How will you retrieve the version number?

IThumbnailProvider and IInitializeWithItem

I am trying to develop an IThumbnailProvider for use in Windows 7. Since this particular thumbnail would also be dependant on some other files in the same directory, I need to use something other than IInitializeWithStream to a path to work with, this being IInitializeWithItem. (Alternatively, I could use IInitializeWithFile, but that is even more frowned upon apparently.)
No matter what I do, I cannot get it to work. I have Microsoft's FileTypeVerifier.exe tool which gives the green light on using IInitializeWithItem, but when explorer calls it, it only seems to try IInitializeWithStream, ever. (This was tested by temporarily implementing said interface, and Beep()ing away in its Initialize()) Did I forget to configure something?
In short: how do I get this to work?
Okay, I finally found out what is the matter. To quote the Building Thumbnail Providers link on the MSDN website:
There are cases where initialization with streams is not possible. In scenarios where your thumbnail provider does not implement IInitializeWithStream, it must opt out of running in the isolated process where the system indexer places it by default when there is a change to the stream. To opt out of the process isolation feature, set the following registry value.
HKEY_CLASSES_ROOT
CLSID
{66742402-F9B9-11D1-A202-0000F81FEDEE}
DisableProcessIsolation = 1
I knew I was running out of process since I read elsewhere that thumbnailproviders ALWAYS ran out of process. But since that particular snippet is on almost -all- shell extension handlers, I interpreted it to be a overly happy copy-paste job, since it was -required- to run in-process the way I understood it.
And I was wrong. I hope this will help someone else in the near future. :)