I'm a total noob when it comes to linking and building with Visual Studio. I would like to integrate Lua into my C++ console application.
Can someone give a step by step on how to do this from getting the Lua dependencies from lua.org, to actually running a "Hello World from Lua" in VS, and all the steps in between.
Finding something like this online has been very difficult since most require prerequisite knowledge of building Lua and such.
Thanks :)
Start with the Lua for Windows package. It will get you a self-contained batteries included Lua installation. Lua for Windows is not an official distribution, but it is well respected by the Lua user community. You can use its lua.exe to gain experience with the language in a Windows environment, and its rich collection of tested extension modules is also available for use.
If you add its include and lib folders to your VS project configuration, you should be able to compile and link against Lua in short order.
One possible complication is that the LfW distribution is built against VC8's C runtime library. If that becomes a problem, then you can either compile Lua yourself as part of your Solution, or get a known good DLL that matches your specific version of Visual Studio from the Lua Binaries project.
Do remember that if you are using one of the distributed DLLs, it will have been compiled as C, and not C++. That means that you must wrap any references to the Lua include files in extern "C" {...} or you will have problems with linkage.
It really helps to have some experience with VS project configuration and building. In particular, experience with mixing C and C++ in a VS project is very helpful.
I heartily recommend following the advice already given about learning C and C++ and mixing the two together. Once you have that under your belt, you may want to check out LuaBind or LuaPlus for connecting C++ and Lua. You can do it manually (and you probably should, at first, to understand what's going on under the hood), but it's more efficient and cleaner, code-wise, to use one of those binding libraries. For debugging purposes, Decoda is a good choice; it can attach to processes started in VS which contain Lua code you want to check.
Related
I am developing a project on C++ which relies on many of third-party libraries (*.lib files and *.h files). I store these libraries in a folder which is not dependant to project, like C:/thirdpartylib. Relative paths is not an option, since it becomes way too long. I have defined connections to libraries in linker setting and in general C++ settings.
But when I pass the project to supervisor he has to reset all paths to libraries to match his environment. We use git, and the project file is being tracked. He stores thirdparty libraries in another way than me.
Is there any way to make a project more portable? Maybe it is possible to store paths in some sort of config files?
As #gaurav says, the way to deal with this in Visual Studio is with property sheets. It's unfortunate that this term is used for two different things in VS, but I guess they just ran out of names (spoiler alert).
These are very powerful, once you learn how they work, and they're just what you need here because they let you define macros, and these macros can in turn be used in the rest of your project to refer to the (volatile) location of your various libraries. This is a trick that everyone who uses VS should know, but it seems that a lot of people don't.
I don't think it's worth me trying to walk you through the mechanics of setting one up here because Microsoft already document it in the Visual Studio help file. Suffice to say, you do it in the Property Manager, that should help you track down the relevant information.
There is also an excellent blog post here which I recommend you read before you do anything else:
http://www.dorodnic.com/blog/2014/03/20/visual-studio-macros/
It's also on Wayback Machine here:
https://web.archive.org/web/20171203113027/http://www.dorodnic.com/blog/2014/03/20/visual-studio-macros/
OK, so now we know how to define a macro, what can we do with it?
Well, that's actually the easy part. If we have a macro called, say, FOO, then wherever we want to expand that macro in some project setting or other we can just use $(FOO). There's also a bunch of macros built into the IDE as listed here:
https://msdn.microsoft.com/en-us/library/c02as0cs.aspx
So, you, I imagine, will want to define macros for the include and lib directories for each of your external libraries and you can then use these to replace the hard-coded paths you are currently using in your project.
And that, I reckon, should sort you out, because the definitions of the macros themselves are stored in a separate file, external to your project file, and different users / build machines can use different files. IIRC, these have extension .props.
Also, you can define a macro in terms of another macro or macros, and that makes the job easier still.
So, who still thinks that Microsoft don't know how to create a build system? Visual Studio is a fantastic piece of software once you get used to it, there's just a bit of a learning curve.
The way to go for large project is to use a package manager. There are some good options out there. Perhaps in windows and visual studio you can use vcpkg or NuGet unmanaged.
If you cannot use a package manager for some reason, the next thing to do is to commit all the dependencies to the GIT repo. If you only target windows platforms like windows 8 or 10 and want to support only VS2017 then committing the compiled dependencies is not a problem. The downside is that the repo will become huge.
For a tiny school project the latter option is viable.
I'm lost here and I have no clue how to proceed. This is not a question about how to make my program work, this is a question about how to stop wasting my time.
My programming environment is Visual Studio 2013 on windows, in C++.
I use 3 libraries extensively, namely: boost (using dynamic linking), OpenCV, and Qt.
During the development, I have configured VS to look at those 3 libraries by default for include and .lib. I have also added the 3 folders containing all the dlls to my PATH environment variable.
It works, but it is sometime painful, let me explain you when.
First hassle: Anytime I have a LNK error telling me I miss a function, it is usually on OpenCV since it has only one include file referencing all the functions. I have to look at OpenCV's source code to see what module this function belongs to and to know what I must link my program to.
Second Hassle: When comes the time to deploy my application, I have to ship it with all the relevant dlls. To know which one I need, I open dependency walker and try to forget nothing, I have then to test it on a different computer because 102% of the time I have missed a couple, and then I have to configure my Installer generator to include all those one by one.
Third Hassle: To ease a little bit the process of configuring a new development machine, I have recently switched to NuGet. It is great, I add boost with a couple of clicks to any project. But now my boost DLLs are everywhere, I have one folder per boost library, and since there are dozens of those I can't even add them all at once to my PATH now, so I have to move them manually to the appropriate folder, and that is really not what I want to do with my not-so-precious-but-who-are-you-to-judge time
I have looked around and couldn't find any good practice regarding this issue, maybe because they are too obvious, or too specific to a particular setup.
How do you do? How would you do if you were me?
We put all our external dependencies in version control along with the code. This ensures that all code can build "out of the box" on any of our development machines and also ensures that for any given version of the code, we know exactly which dependencies is has.
The best way to check for missing dependencies is how have a good automated test suite, if you've got comprehensive converge then if your tests pass you must have deployed the required libraries.
In terms of linking to the appropriate libraries, unfortunately, that just sounds like an issue with the structure of OpenCV (I'm not familiar with OpenCV). I tend to use dumpbin under Windows and nm under Linux to easily grep for symbols when I get link errors with an unfamiliar library.
I'm trying to write my first game in c++, and I want it to dynamically load everything from files. This includes the enemies, and I was wondering if there was a way to dynamically include their code at runtime, instead of linking the on compile, so that the levels are easily interchangeable. Lua might be an option but I have no clue where to start, and dll seems to be Windows-only (and I wouldn't know where to start there anyway). Can anyone help with this?
tl;dr I want to link in code to my c++ game at runtime.
For the Lua approach you first need to choose the version first. Right now there is the major version 5.1 and 5.2. My previous work was using 5.1 and for my new project I decided to update to 5.2, however I found that my favorite script wrapping tool (SWIG) does not work with 5.2. Just something to decide at the beginning, because you do not want to get a version working and then have to change it.
Lua comes with makefile build environment. My first experience of trying to build on Windows was a bit of a nightmare, did not appear to just run out-of-the-box, so I opted to create my own Visual Studio project at the time, and just include all the .C files in the project. There are two files which need to selectively included/excluded depending on how you intend to compile: lua.c and luac.c. If you are planning to embed Lua in your app, then exclude both of these files; they both contain a main() function and are designed to build console apps. Include all the rest of the C files in your project.
You should be able to compile easy from this point.
When you include the headers of Lua, keep in mind that the functions are C functions so if you are including them from C++ you need to wrap the file inclusion inside of: extern "C" {} - example: C++ Lua 5.1 Issue
Wrapping your interfaces in another topic and there are lots of resources available. My favorite is SWIG but there are lots of options, including hand coding the conversion of your C/C++ -> LUA -> C/C++ code. Would recommend just focusing on getting the first part working first, get the interpreter embedded so that you can run a "hello, world!" script from Lua inside your app.
So going by your requirement of crossplatform use and dynamic linking, what you're probably looking for is an environment like QT which has QLibrary: https://stackoverflow.com/a/9675063/453673
But https://softwareengineering.stackexchange.com/questions/88685/why-arent-more-desktop-apps-written-with-qt
MingW is the open-source equivalent for Visual C++, so it can help you writing code for Windows (though if I had a choice, I'd directly use Visual C++). The way dll's are loaded in Windows is somewhat similar to the way they're loaded in Linux, so you'll be able to write code with #ifdef's to do conditional compilation. I've written one such program a couple of years back.
To load a shared library(always with .so as suffix) under Linux, you could use dlopen(), dlsym() and dlclose()
The situation is the following: I have the source code of one programm (lets call it programA) (written in C and C++), as well as the CMakeLists.txt and CTestConfig.cmake files. I already installed programA using CMake's graphical user interface and, as it is obvious, it worked. It created the .exe file (I'm working on Windows 7 OS).
The problem is that, right now, I've been asked to edit the program (and so, I must be able to edit the code and degugging it as changes are made). I also need to compile it but not in .exe anymore but in .dll so I can add it to a website we have.
I've read in forums that CMake can compile programA into a .dll if I need to, but as I would need to make some changes I consider that CMake debugging is not as useful and easy as using entirely VS. From the little I know from CMake language, the CMakeLists.txt is mainly used to check the OS of the user as well as adding some libraries in case they are not found.
I have to admit I have no idea in programming CMake directives, as I have been working with ASP.NET, C, C++ and C# mostly. Then, my idea is to try to work only in visual studio 2010 instead of using cmake as well, so once I have the program 'adapted' to VS and can be compiled just using VS, I'm ready to start my job. So the question I have is how can I perform the same task CMake did just using Visual Studio (Is there any way of implementing CMake directives in VS?), can VS compile by receiving as an argument something similar to that CMake.txt file (though it needs to be translated into another language)?
To skip the use of CMake I tried to copy the source code into a new project in VS. However as it does not use the CMake directives when compiling, it gives several errors, most of them related to the fact that some headers.h can't be found (cause they might be in a subfolder). And there are so many subfolders to add the paths to the predefined directories of search that it would take ages.
I'm sorry I can't be more precise in my explanation. I'm good at programming little projects on my own, but it's the first time I have to work on other's programm. Please don't hesitate to ask if anything was not properly understood
I would appreciate a lot any suggestion / advice /guidance you can give.
To make a dll, use add_library command and the SHARED keyword
add_library(mylib SHARED ${files})
this is easy with CMake, don't go back in visual that will be harder at the end
The Good News
Fortunately, cmake can generate VS Projects automaticaly for you (this tutorial s specific for OpenTissue, but Steps 1 to 3 should be the same for you).
The [not so] Bad News
Depending on the complexity of the project, VS Projects automaticaly generated by cmake can get pretty nasty, to the point of illegibility. It will, for example, hard link any library dependencies using the specific paths of your machine, so the project will most certainly not be portable across setups. In any case, that's the intended bahavior, because the primary idea of supporting this generator is simply making it work, thus allowing users to easily compile projects using MSVC, so there's not much you can do here. Nonetheless, it should work in your machine and will certainly be a great starting point for you, just create a project yourself from scratch copying the relevant parts out of the automatic generated version.
I am currently working on an opensource C++ project. I don't have much experience in C++ as my daily job mainly involves with Java. I am now planning to release my C++ project and I would like to know how should I should I arrange the packaging of my project. E.g, in Java, all the class files are packaged into jar file. So what is the equivalent approach in C++? Is there any good practise for organizing the source code/binary? My target platform is Linux by the way.
Another question is I am currently using Eclipse CDT plugin for development and building. So is there anyway that I can extract build script from Eclipse project and use it as generic build script? Is there any good reference regarding C++ build/packaging? Thanks in advance.
Edited
To clarify a bit more, I think the release of my project can be considered as an application. It's a command line tool for software configuration management.
I am currently working on an opensource C++ project.
That simplifies many things. You should supply the build scripts for you project and support them for different use cases (learn about Makefiles, there are similar concepts like "target").
I don't have much experience in C++ as my daily job mainly involves with Java.
Most of the things you're used to have (and ask for right now) in Java are invented because they lack in C/C++. Learn at least something about dynamic(shared)/static libraries (.so and .a files to be simple).
I am now planning to release my C++ project and I would like to know how should I should I arrange the packaging of my project.
The "packaging of a C++ project" is something informal. You may supply the sources, build scripts and some project-files for the well-known IDEs.
EDIT: you've specified that you're building the command-line application. I believe all you need is to start from a simple Makfile for that application. The reference Makefile can be automatically generated by Eclipse. If you are planning to deploy your application as a stand-alone software, then you have to earn about packaging (rpm, deb, tgz).
E.g, in Java, all the class files are packaged into jar file.
There are no such thing as a C++ "package" compatible accross compilers (even the "modules" were rejected in the latest C++11 standard)
because there is no binary standard to encode C++ classes (ABI). On linux you're most likely going to use GCC (or Intel's compiler, or LLVM's CLang, or custom build of OpenWatcom or...),
but the version of standard library you are linking to makes the release of binary builds close to useless.
That is the reason for redistibuting source code.
So what is the equivalent approach in C++?
No clear answer here.
Is there any good practise for organizing the source code/binary?
Look at the large-scale projects, see the way they organize their builds. The term "build engineer" as an occupation emphasizes the difficulties of large-scale projects compilation/linking.
My target platform is Linux by the way.
This is also something of an incomplete description. "Linux" is a blurry term. You should speak about the Linux distribution, compiler toolchain and package manager. E.g., Ubuntu 12, amd64, GCC 4.6 toolchain, APT package manager.
There are different "linuxes" built around the same kernel source. There are different compilers. There are at least three major package managers to consider: Debian/Ubuntu(deb,apt), Red Hat(rpm), Slackware(tgz).
Another question is I am currently using Eclipse CDT plugin for development and building. So is there anyway that I can extract build script from Eclipse project
There's a sort of "meta-technique": you write a "description" of your project and then a tool generates the project-file and build scripts for your sources. Have a look at CMake. Since you're on "linux", try looking at the somewhat standard way of autotools (autoconf).
Is there any good reference regarding C++ build/packaging?
You should start by building your application and then move on to the deployment issues. C/C++ is a hard-to-learn legacy with a lot of subtleties which are avoided in Java.