Using libcurl without installing it - c++

How can I use libcurl with my project without actually installing it or curl on the system?
I want to make my source-code portable, so that any developer can copy the folder with all sources and other files, run make and compile the program without the need for system level installations.
I am looking for (probably separate) solutions for Linux and for Windows (dll?). If it is possible, provide some standard/official solution and not hack (I'd like to be educated about linking third party libraries)

I've used it on Windows using Visual Studio, all you need to do under Windows:
Download the source
Using CMake generate the project files (when using Visual Studio).
Build the libraries, 3 files will be built: libcurl.lib, libcurl_imp.lib and libcurl.dll
Include curl.h in your project and add the paths to your .lib files
Build your program, put libcurl.dll in the executable folder and it will work.
On Linux it should be a similar process, build the libraries and include them with your source.

You probably want to build a static library out of libcurl and link agains it. Should be pretty straightforward and the process is almost identical on every OS.

Related

How can I add libraries to a project in a system independent way?

I'm developing an application using Qt and OpenGL, and found it necessary to download the GLM library. It's a header-only library, so I don't need to link to anything. I want this application to build on any system that has the correct libraries installed. My problem is that I don't know where to put GLM so that the system can find it without adding a specific path to the project's .pro file. The .pro file is part of my git repository, which is how the source is distributed to other systems like Linux, etc. So I don't want this file to specify the exact location of GLM because other systems could have it in other places.
I'm currently developing on Windows, compiling in Qt Creator using Visual C++ 2010. I read from MSDN that #include <file> searches using the INCLUDE environment variable, so I tried to add the path to glm.hpp to INCLUDE, but QtCreator's build environment for this project seems to overwrite INCLUDE. So I appended the path to GLM to the new INCLUDE from within QtCreator's Projects tab, but my code still can't find glm.hpp.
In general, how can I add an external library to my system such that my compiler will be able to find it without specifying the exact location in a project file that's distributed to other systems?
What you need is a build system with the power to search the system for the libraries you request, and be able to do so on any platform. One such build system is cmake, and it is the most widely used build system. In essence, cmake allows you to write a build script in which you can specify all the things you normally specify when creating a project in Qt Creator or Visual Studio, like the list of source files, grouped by targets to compile (libraries, executables, etc.), the relative paths to the headers, and libraries to include for linking and for include-paths, amongst many more things. For libraries that are installed on the system, there is a function, called find_package() (part of cmake script commands), that will find out if the library is installed and where to find its lib files and headers (storing those paths as cache strings that you can specify on the targets and such). It usually works great, as long as the libraries are not installed in weird places. The way it works is that when you run cmake, it will generate a build script/configuration for almost any platform you specify, and then you use that to compile your code. It can generate makefiles (Unix-like or windows), CodeBlocks project files, Visual Studio project files, etc.. And many IDEs also have native support for cmake projects.
I wish I could recommend an alternative, just to sound less biased for cmake, but I haven't heard of any that truly compare to it, especially for the purpose of locating external dependencies and working with different platforms. I would guess Boost.Build is decent too.

How to package C++ with dlls and libraries

I'm wondering how to "package" a C++ project for release. It uses various libraries, and I don't want a user to have to go through the same setup I did, with putting the right files in the right place and such. I had difficulty researching this, because I'm not sure the technical term for this issue. If I'm using command line compiling on Linux, is there an easy way to do this?
Your approach to this will differ on Windows and Linux because each OS handles this a different way. I'm more familiar with Linux so I'll restrict my answer to just the Linux side of things.
When you link your executable with a library using -l flag the linker defaults to looking in the normal system library directories so there are four approaches here.
Require the user to properly install the libraries themselves. However, it sounds like you don't want to do that.
Have the user add the library location to LD_LIBRARY_PATH variable.
Your third option is force the linker to look in a certain path for the libraries using the -rpath flag. For example, to have the application look in its working directory for a shared library you can compile with: g++ -rpath ./ -l SomeLib -o MyApp myapp.cpp
One other option is to static link your code with their library that way you only have to distribute one executable. If a static library exists you can use g++ -static -l SomeLib -o MyApp myapp.cpp to tell gcc to link statically.
On windows I would recommand wix http://wix.sourceforge.net/ to create the .msi installer
I would like to point out, the lookup path for .dlls I recommand putting all .dll in the same folder as your .exe since this has the highest priority
However, the vc crt (the c/c++ runtime library) should be installed using the redistributional package from microsoft -> updates automatically http://www.microsoft.com/de-de/download/details.aspx?id=5555
Wix can include the redistributional package into the same .msi therefore you have only to deploy a single installer file.
You mean an installer?
On Windows the program that you run to install a new app which outs everything in the correct directory, creates the start menu and lets you un-install it?
There is an installer builder in Visual Studio (might not be in the free express version) which makes .msi installer files. It's fairly easy to use for simple tasks but becomes complicated to do anything more.
Alternatively, to create traditional setup.exe type installs I use the excellent free Innosetup
On linux you would generally create a package using whatever format your distribution uses (.deb / .rpm ). There are lots of instructions on the specifics of each one and the tools to do so will probably already be installed in your Linux system

Build boost.Log on Windows 7

I recently downloaded http://boost-log.sourceforge.net/libs/log/doc/html/index.html but I can't seem to find out how to build it. The rest of my boost lib was installed by using the installer, so all I did was selecting the files I wanted to include.
So how do I build Logs? Building for windows is completely new to me and I would really appreciate any help!
EDIT
Merge boost.log in the boost directory structure first.
Did you build boost ? If not, you have to go to your boost directory, run boostrap.sh and then run b2.exe. That will build all boost libraries.
Since you are on Windows, boost supports automatic linking, i.e. you just include the header files and the required libraries will be linked automatically when building your project from Visual Studio.

How to include boost::filesystem into a VS2010 project without adding a dependency on bjam?

According to this answer, the intended way to include non-header-only parts of Boost into a Visual Studio 2010 project require the use of bjam to build the correct libraries.
What is unclear to me is whether this is a one-time-only thing, where I just check in the lib files produced by bjam, or whether anyone who wants to build my project will from now on require not only Visual Studio but also bjam.
The project only targets Windows 32-bits, because it builds a plugin for a program that's only available in this configuration, and only needs to support the statically-linked multi-threaded CRT.
(For the record, if I just include the relevant .cpp files into the build, the compile stage succeeds, but at link stage I get a missing library error, which is apparently caused by the "auto-link" feature. Perhaps I should just disable auto-linking, if it's possible?)
You don't need bjam. Like yasouser answered, you can download the installer from boost pro, the downsides being that
you need to register though that's quick and easy
it's usually/sometimes a release or two behind the latest boost release.
What is unclear to me is whether this is a one-time-only thing, where I just check in the lib files produced by bjam, or whether anyone who wants to build my project will from now on require not only Visual Studio but also bjam.
It is a one time thing per machine. Once you have the boost binaries you don't need bjam anymore. The nice thing about the installer is that you can install some selected versions of the boost libraries + the headers (You can select VS version, single-threaded, static/dynamic, etc. on a per library basis e.g. thread, system, etc.) and then at a later point you can just run the installer again and add other binaries.
So if you're auto-linking and are missing a specific lib, just run the installer again.
FYI, you can disable boost's autolinking option by defining BOOST_ALL_NO_LIB and then manually linking in the lib versions you want.
Some of the boost libraries require you to build them as static or shared libraries and link them in your project. Either you can download the source and build it for yourself using bjam or you can install the pre-built binaries from here.
Yes this is a one time install (if you are installing from pre-built binaries or built by yourself). And those building your project will also need to do the boost install once for them to be able to build your project.
if I just include the relevant .cpp
files into the build
Direct including cpp files has many drawbacks. The only reason of borrowing .cpp files I can imagine is to allow build the project on other PCs without installing boost there. But I think it can be solved by distributing particular boost .lib files as well.

Compiling libpng and using it with netbeans and mingw

I have only previously used visual studio for developing c++ but I've just moved to netbeans and am having some issues.
I got mingw installed so that my projects will compile but I dont know how to add external libraries to that. I want to use a static library, not a dll.
The library I specifically am looking at is libpng
I hope this isn't too IDE specific, I'm also looking to know how to prepare the library.
Windows OS.
I figured it out more or less. I used the cmake gui, configured for msys make and mingw g++ and gcc, on the zlib source directory and then ran msys make and make install on the output directory. After that I did the same on libpng, but I had to add some variables to point to the zlib include and library directories within cmake.
Then in netbeans, I right clicked>>properties on my project and added include and lib location for each of the two libraries. I also could have copied the files into my mingw directories.
Now I'm just stuck with this issue.