I'm relatively new to Swift (I've tinkered with Python and HTML in the past)- but I'm currently working on an app with a group.
This app already exists as a desktop program written in Ada and we were hoping to port it over to Swift and put out an iPhone app.
My understanding is that I can (likely?) turn the Ada into C with a converter, then reference the C in Swift? Is this correct, or have I overlooked something due to not being familiar with the languages?
If correct, how would I go about actually executing this since I have little experience in Swift and C?
This is a pretty loaded question, so thank you for any help or insight!
edit: said desktop application is open source and available for all use- I do not intend on stealing anyone's work
I'm assuming that you can easily pull out the parts of the Ada program that you want to use in the iPhone program. If the code that you want to port over has other dependencies, then you have to make sure that you can get all of these dependencies for iOS as well. This may be extremely difficult for UI toolkits, if you use one.
To call foreign functions in Swift, you usually need to use a bridging header. Your target's bridging header contains C and Objective-C declarations of classes, functions and variables that Swift should be able to call into. As long as the language that you want to call into can export C-compatible bindings (which should be the case of Ada), then you will be able to call these bindings by declaring them in your bridging header.
If the part of the desktop Ada program that you want to use can easily be isolated in a library (static or dynamic), and you are capable of building that library as an ARM Mach-O library, then it's simply a matter of declaring the functions that you want to use from the library in your app's bridging header. You can refer to GNAT User's Guide for Native Platforms: Interfacing to C for the directives to use to expose an Ada function to C, and by exposing it to C, you're also exposing it to Swift. I'd try this first, as maintaining the almost-unmodified Ada source is almost certainly going to be easier than maintaining a mechanically-translated C version of the Ada source.
If that doesn't work, then yes, translating the Ada source to C code will also allow you to reference it from Swift. You will also have to ensure that the functions that you need to call are declared in your bridging header.
It looks like it used to be possible to compile Ada in Xcode when Xcode still supported the GCC compiler. That was removed a while ago.
If there are translators that will translate Ada to C then you could use C natively in an Objective-C iOS app. (Objective-C is a pure superset of C, meaning that all C code is also legal objective-C.)
Swift "plays nice" with C and Objective-C as long as you limit yourself to the types and classes that C and Objective-C understand, but inter-operating between Swift and C/Objective-C is somewhat tricky and tedious. You would have a fair amount of reading and study to do in order to learn how to build an app that uses both, on top of everything else you would need to learn.
Unless you're dealing with many thousands of lines of Ada code it might be better to find somebody who knows both Ada and Swift to translate the code for you, or for you to learn Swift and then translate it yourself.
Unfortunately, There is, at this time, no Ada compiler which targets iOS available to the public.
If you have cash to spend you could contact AdaCore for one, don’t expect it to be cheap though.
Believe me, there are some of us who would like to target iOS with Ada.
I am only aware of two Ada to C compilers, the most powerful one (AdaMagic) is now known as MapuSoft Ada-to-C/C++ changer. You'll need either Windows or Linux execution environment to run translator (Wine, Docker, etc. on macOS). Also, you'll need to limit yourself to Ada 95. AdaMagic is said to support a "subset of Ada 2005", but I am yet to stumble upon this subset. Also you'll need to port the runtime or a part of it. If you disable runtime checks, the amount of runtime required to port becomes lower, so it is up to you how much time you are willing to spend on it.
It has two modes of operation, either targeting C, or C++, I recommend C++ because throw-catch is a better match with modern Objective-C runtime (utilizing C++ ABI behind the scenes) than C setjmp/longjmp.
With some effort you'll get something up and running.
It is a pity Ada developers are so unaware of this option. Maybe somebody could find time to port AdaMagic to EmScripten, iOS, Elbrus or whatever essential target the humanity is missing to start mass Ada adoption.
Others advised producing Swift bindings from bridging headers, but IMO the winning strategy would be to write glue code in Objective-C++ hybrid. Objective-C++ will have access to both Swift code (viewed as external Objective-C classes) and Ada-to-C++ translated code. For instance, it will be able to catch C++ exceptions from Ada and throw Objective-C ones or vice versa.
Another compiler is GNAT CCG aka SPARK2C. It is designed to target embedded devices having no other Ada compiler. It supports recent Ada standards, but is very limited with regards to features requiring runtime. Basicly, there is no runtime. No runtime, no problem. Nothing to port. In this compiler one can return limited record from function (Ada 2005+ feature), but cannot have RAII, tasking, etc. I guess, that are far more strict requirements than Ada 95. GNAT CCG is not yet publicly available, but I expect it to appear before annual Make with Ada, otherwise that would be a very stupid situation.
Another options are Ada-to-Java or Ada-to-.NET, maybe they can work for your application better than others.
Related
By checking the Codename One website and ParparVM Github, its guide only show how to build the Java (with Java Main function entry point) into the native executable/app (iOS), but I can't find any guide to build/compile Java into iOS share library (either in C source or binary, as long as can be reused by swift/objective-C from iOS app).
So are we able to do so? is there any guide for that?
It wasn't designed for that purpose so it probably won't work well for it. There are some inherent design decisions that would make it very difficult to get ParparVM to work with a library. Two big ones:
The GC needs to work with roots and would have a hard time collecting without full control of the app
The code generated looks "awful". Method names translate to very long function names in C with a very convoluted syntax to allow all sort of VM edge cases such as covariance
I suggest you look at J2ObjC. I haven't checked it out in ages but it was designed exactly with this use case in mind. It doesn't have a "real" GC but that might be OK with ARC. It works with your sources and produces libraries that look a bit more "natural" on iOS.
I'm interested is it possible to install and use Android Things(former Brillo) on custom produced hardware?
I can see from the official documentation there is preselected and certified SoMs listed, but I'm interested in using my own hardware.
Is it possible to have best of both worlds - use the familiar to me Android & Android Things but run it on proprietary hardware?
If not, what other options do I have - I researched about micropython, but apparently it seems it also comes with designated board(pyboard).
So my question is what are options to not thinks too much about the firmware on the device(and write C code), but focus on more higher-level business logic and programming languages(Java, Python).
Android Things isn't open source, so you can't put it into that isn't officially supported.
If you're looking for custom options, you will need to find a compiled language like C that works for that board. While C may be a bit intimidating, you may be able to find languages that compile to similar machine code. Rust and Go may work on microcontrollers too if you check.
I'm not too familiar with micro python. It says that it compiles to bare metal/machine code, so I believe you should be able to use it on other boards. While they may officially support the compiler for one board, the community may have support for additional microcontrollers.
I work with an App that's 100% Objective-C and I'd like to start transitioning over to include Swift. Due to the size of the codebase, it's unrealistic that I'll have a 100% Swift app anytime soon.
As soon as a swift file is added, I noticed that the app size increases because now, the app needs to the include Swift run-time.
How else does things change? As soon as you include a Swift file, what is the process that the compiler and linker undergoes to ship a binary that is now multiple language & related frameworks?
Are there any other caveats in transitioning into a mixed language world in a somewhat large codebase?
In my experience, it works surprisingly well. It is advisable however, to wait to Xcode 7 / Swift 2.0 / Objective-C with generics support as that will eliminate a round of updates, allow you to interop from Objective-C with more elegant Swift code, and eliminate the Swift RT linking concern now that they have stabilized the runtime.
Aside from that, both compilers need to run, Swift first, Objective-C second, the swiftc compiler can be pretty fast or really really slow, depending on what innocent and otherwise legal Swift code that you write (this is also true of a Swift-only app of course).
Getting started, you need to read the interop guide, learn how the bridging header works, and are then mostly on your way. I would say that having a mixed app is actually a blessing as you are not pressed to learn and do everything at once. Opinions will vary of course, but this is mine.
I am familiar with Matlab and would like to use what I know to add the functionality I am looking for in my iOS application. The title really says it all, I would like my app to be able to use the mathematics capabilities that matlab provides like integrals, derivatives, cross products, etc. not any graphing or any of that but just basic equation solving things. Is there a way to add this functionality to it while keeping my application agile. I have heard of the matlab coder that allow code to be switched from matlab to c or c++ that could be used for an Xcode project. If this is the best solution, is that a very difficult coder to work with? This is my first application, I have literally been working with Xcode and objective-c for a few weeks but I have the basic framework of my application good to go. I need this to add the real functionality to it and make it very useable. Please go easy on me if any of my questions seem obvious, I'm a nube, I really appreciate your answers.
Josh
As you mentioned, MATLAB Coder can generate C code from your MATLAB function. The header (.h) and source (.c) files can be plugged into your XCode project. The key part of the work is to decide what the input and output of the function should be and how to interface the rest of the XCode project with the Coder-generated function. Also, existing MATLAB code may not be completely compatible with the Coder, so that some modifications to your MATLAB code may be necessary. The Coder has interactive processes that guide you through this process.
If you haven't done so yet, you should start by looking at some examples of MATLAB Coder provided by MathWorks, e.g.,
http://www.mathworks.com/help/coder/examples/c-code-generation-for-a-matlab-kalman-filtering-algorithm.html?prodcode=ME&language=en
I would like to try some ARM assembly code with apple iOS just for educational purpose. I would like to start with some in line code within Xcode.
My understanding is that I need to compile for a iOS device, for example for my iPhone, which means that I need to pay $99/year for membership.
I don't think I can use ASM assembly code with a iOS phone simulator.
I am having an hard time on finding examples, books or documentation on ARM assembly code in Xcode env with an iPhone.
Am I doing this wrong? Maybe iOS is not the most user friendly environment to learn ARM Assembly.
Back up...
What are you trying to learn? Arm assembly or iOS programming? Pick one...
Do you have any assembly experience?
What is it you think you are wanting to learn in arm assembly? Jump in and write some full blown gui applications? You need to learn to put immediates in registers add and or and xor and save answers in registers. then read and write some memory locations. Learn to use the stack, make calls, etc. Then write your applications in C or whatever and use asm for hand tuning or use your asm skills to debug the compiler and or code. Writing applications or operating systems, etc in asm is for folks who want to make a statement, or have a specific reason, not for educational purposes.
There is some leaning toward a unified ARM assembly language that works both on the ARM based cores and the thumb2 based cores. Not for all of the assembly language needed but for places where you might want to write a module of code and not have to have a lot of if thumb elses littering the code. You can certainly get your feet wet with that here and take some of that code straight to full 32 bit ARM instructions on some other platform. thumbulator is thumb only, the common instruction set between the ARM based cores and the thumb2 based cores, basically it is the portable ARM instruction set, write the code once, it works on almost all of their cores.
If your goal is to learn iOS programming, get the kit or whatever and learn using whatever language they want you to learn, get proficient at that, learn the apis, etc. Then if you do some of the assembler stuff above then you can start to think about making calls to asm functions or inline assembler, etc, from your iOS programs. How much assembler, your choice. I wouldnt expect to see applications written in assembler for that platform I would instead search for how do I call this assembly code from my ios application or how do I do inline assembly. (dont learn inline assembly until you are good at real assembly).
There is no reason at all to pay for access to a simulator, there are many many arm simulators out there, one in mame, arms armulator in gdb and other places, a number of gameboy advance and nintendo ds simultators, etc, etc, etc. Of course there is qemu-arm. there are more simulators than you probably are willing to take the time to try, i am about 10 years or so into it myself and not tried them all.
learning assembly is not like C or python or java, I will write a minesweeper game to learn this language. You are learning the mechanics of moving the bits around, small steps, not writing usable applications. For example adding two 128 bit numbers using a 16 bit processor is a worthy assembly language project. Multiplying two numbers, any size, with a processor without a multiply instruction, that is another assembler type learning project. yes, I agree you CAN learn those things by calling asm from an iOS application, but if you dont already have the iOS developers kit and know how to write iOS applications, you have a lot of learning to do before you start thinking about assembler.
If I am way off the mark with what you were asking, no problem I will gladly remove this answer...
Even without a code signing cert, I think you should be able to go to the scheme pop-up menu (the right side of it) and choose "iOS Device"
Once you do that, then you can choose any .c or .m (or .cpp or .mm) file in your project, open the assistant editor, and choose "Assembly" from the assistant editor jumpbar. Then you can see your source code and assembly code side by side.
Or you can just go to Product menu and Generate Output -> assembly
You may find it easier to start with C code, where the function calls will be much easier to follow initially than Objective-C method calls.
What you need is an ARM development kit with a Linux-based programming toolkit. You can then install VirtualBox on your Mac, create a Linux virtual machine and install the ARM development tools on the virtual Linux machine. Make sure that when you buy an ARM dev kit, it comes with the ARM cpu, complete dev/test board, USB cables for software transfer/debugging and the complete Linux toolchain. You can find such kits for less than $99.
Another quick introduction to ARM assembly and reverse engineering: http://yurichev.com/writings/RE_for_beginners-en.pdf