I am trying to port some c++ code to my android application using NDK.
But the c++ code involves calls to some pthread_rwlock functions which is absent in the libc provided with the NDK.
I have found implementations of these functions but including them, it asks for more header files and more implementations and the problem grows.
Does somebody have a solution to this.
Thanks!
I stumbled over the same issue with NDK r5b where rwlock was in the header but not in the lib.
In the latest r5c this seems resolved.
Android's pthread implementation lacks read/write locks. You'll need to use standard locks instead. A work around may be to write some wrappers that simply use the standard locks. Another approach may be to use Android's atomic APIs to roll your own.
Relevant items in the AOSP bug database:
pthread_rwlock functions are missing
pthread_rwlock static init constant is broken
Related
New to Swift, couldn't find an answer to this with a reliable source.
I have some commented code, but would like to know if they are removed when compiled/run in Debug/Release, and if this is enforced or can be turned on/off.
If they are indeed removed, what about those instances where I really need them to be inside, e.g. some framework or something?
Thanks in advance!
If you create inline docs in a swift package, they're available to the consumer. If you provide a Docc asset, that will also be available to the consumer.
If you create a binary, that depends on how it's created and distributed.
Unless there is a security concern not to share the source code, I would do a vanilla SwiftPackage with documentation comments.
I'm trying to find more information / explanation for the following scenario:
I'm writing a library in Swift and would like to use some open source library in it.
If I just integrate them into my library, is there a chance of namespace collision?
What would happen if the host app will use:
The exact same open source library
The same library but different version
Does using CocoaPods changes something here?
Consider a scenario where I import AFNetworking for example (via CocoaPods) in my library, and the host app will use it too.
Using the same library, you won't have any issues. Using different version will likely cause problems, but that is going to be dependent on the changes made in the different versions.
Namespace collisions in Swift are rare. As #mattt stated, each module acts as a namespace, so naming conflicts with classes or functions from another module won't exist as they do in Objective-C. If you have a naming conflict, the compiler will tell you. In that case, you can just prefix the conflicting signature with the module name.
I would highly recommend you use Cocoapods for dependency management. It handles version control and will make your life much easier.
I saw them in libc-8XX/pthreads on opensource.apple.com, but since libc-9xx the pthreads folder are gone, so did these two functions. I saw these two functions were used in _Unwind_SjLj_Register in exception handling on 32-bit IOS platform, but where are they now? or am I just misunderstanding something about them?
I have just finished porting a decent amount of c-sources to the iOS platform and packaged them as a universal static framework. I, then, added the framework (not the project) to a sample iOS app in order to test linkage and proper function. That's when I ran into a humbling problem.
In my attempt to solve the problem described here, I also came across some symbols that are composed through the heavy use of macros (i HATE those). Some of those macros use function attributes that are really extensions of gcc rather than of standard C.
Of course I can always add -std=gnu89, but even then, I am not sure it will resolve the original problem of undefined symbols in the static library.
Not only that, I am now worried that my port to iOS of those sources may not be an accurate port and may result in the type of bugs/issues that maybe related to compiler's codeine and/or optimization policies.
If you can share some of your experience/advice in how best to go about that port, I would really appreciate it.
Thanks!
From manual testing with clang 8.0, it seems that both __attribute__((constructor)) and __attribute__((__constructor__)) work for your purpose.
Hi, I'm just wondering how you could obfuscate functions in iOS binary?
If you tried to reverse iOS binaries using tools like ida you will see part of the binaries have obfuscated functions like all or partly named sub_xxxxxxxx but the other have human readable functions
Someone said, add those lines to the top of your header without any further explaining:
#define SecurityClass ah7p
#define checkCopyProtection xcyc
What the methods used to secure your App?
Sorry for the dumb question, but I'm new there and I ended up with no answer explained what I need.
There are a couple of ways to obfuscate an iOS binary.
Open Source compiler named llvm-obfuscate (https://github.com/obfuscator-llvm/obfuscator/wiki) It has some nice features to obfuscate during compilation. You are replacing your default compiler with that one.
There are for Windows of course VMWare oder Themdia that can post process but that is not the case.
Besides that I just know one more which is Liasoft antispy. It is a very advanced anti analysis toolkit that allows you to encrypt functions and much more during compilation using mixed Objective-C and C++ code. ( https://www.liasoft.de/en/products/antispy/ )
Not sure if one of these is the right one for you. Except these things you are pretty lost since Objective-C is a compiled language with lots of metadata.
Hope I could help you, this is my first post.
If you only care about obfuscating method names then the easiest way is to write relevant parts of your application in C or C++. For instance, you can rewrite your SecurityClass as a C++ class instead of Objective-C class. This will not make your code reverse-engineering-proof, but it will at least raise the bar a bit. (NOTE: I'm not saying this is the right thing to do from software engineering point of view, though).
If you need to obfuscate code, then you are in a search for a tool that can do this. There are several such tools, both commercial and free. One project for doing exactly this is obfuscator-llvm.