The article describes the main preconditions and stages of development of open VivaCore library intended for code analysis and creation of metaprogramming systems. VivaCore project is a development of OpenC++ library in which support of C and C++ language peculiarities specific for Visual Studio 2005/2008 is implemented.

1. How VivaCore library appeared
Author: Andrey Karpov
Date: 10.08.2008
Abstract
The article describes the main preconditions and stages of development of open VivaCore library
intended for code analysis and creation of metaprogramming systems. VivaCore project is a
development of OpenC++ library in which support of C and C++ language peculiarities specific for Visual
Studio 2005/2008 is implemented.
Introduction
This article is intended for software developers who use or plan to use VivaCore library in their
developments. The article touches upon the history of creating VivaCore library and relating peculiarities
of the library's implementation.
VivaCore library is a project with open program code built on the basis of an older library OpenC++
(OpenCxx). VivaCore library is implemented in C++ and meant to be used in VisualStudio 2005/2008
environment.
VivaCore library was created and continues to develop thanks to OOO "Program Verification Systems".
VivaCore code analysis library has a State Computer program certificate N 2008610480.
You can use VivaCore library free. The only license limitation concerning it is the necessity to mention
that your project has been developed on the basis of OpenC++ library and its development VivaCore.
The library is used to develop projects in which analysis of source code of C and C++ programs is
performed. Such an example is systems of language syntax extension, code editing and coloring systems,
static analyzers, systems of building documentation on the code. To learn more about the library and
possible ways to use it see article "The essence of the code analysis library VivaCore" [1].
VivaCore library as part of Viva64 product
Creation of VivaCore has never been planned purposely but it appeared in an absolutely natural way
while working on Viva64 project. Viva64 product is a specialized tool for testing source code of C/C++
programs to establish if they are compatible with 64-bit platforms [2]. Viva64 is a typical static code
analyzer meant to help programmers while developing 64-bit applications.
Of course, an essential part of Viva64 project is the system of parsing source code of programs for
further analysis. OpenC++ (OpenCxx) was used as a library for code parsing. On the initial stage of
Viva64 product's development its inner structure was as shown on Picture 1.

2. Picture 1. How we imagined Viva64 project's structure to look.
As seen from the picture there was the code of Viva64 project which used functionality of OpenC++
library inside it.
But it became clear already at early stages of implementation that OpenC++ library doesn't implement
the whole necessary functionality, contains some disappointing errors and doesn't support fully key
words used in Visual C++ compiler. This was the stimulus to develop new functionality and improve
OpenC++ library.
Let's give some examples of improvements. C language support was implemented (OpenC++ works only
with C++ code) as well as calculation of values of literal constants. Specific key words __noop,
__if_exists, __ptr32 became supported too. And so on.
As the result of these changes, large code has been written which related to a code analysis library in its
meaning, but it was implemented in Viva64's code. Because of it Viva64's architecture looked as shown
on Picture 2.

3. Picture 2. Implementation of functionality relating to C/C++ code parsing in Viva64.
It became evident that some functionality relating to code parsing should be enclosed into a separate
module. Thus VivaCore library appeared. Although its code was still inside Viva64 project, it was
separated logically. Viva64's structure became as shown on Picture 3.
Picture 3. A decision is made to enclose functionality relating to C/C++ code parsing into a separate
library VivaCore.
The new architecture where code parsing functionality was enclosed into a separate subsystem
VivaCore was convenient for us. But we decided to go further.
VivaCore library's independent life
We decided to provide other developers with an opportunity to use new abilities implemented within
the framework of VivaCore. It turned out to be too difficult a task to update OpenC++ library up to the
necessary level. That's why we decided simply to make VivaCore library a separate project (Picture 4)
and put it on OOO "Program Verification Systems" site. You can download source code of VivaCore
library here: http://www.viva64.com/vivacore-library/download/.

4. Picture 4. Viva64's new structure.
Now VivaCore library can be used not only within the framework of OOO "Program Verification
Systems" projects such as Viva64, VivaMP, but in projects of third-party developers as well (Picture 5).

5. Picture 5. Open library VivaCore for developing projects dealing with source C/C++ code.
Besides VivaCore library itself developers can download a demo program VivaVisualCode [3]. It shows
some abilities of VivaCore library by an example of graphic representation of a parse tree. An example of
such a tree is shown on Picture 6.

6. Picture 6. Parse tree for expression "const bool is64bitInt = sizeof(int) == 8;".
Peculiarities of the library relating to the history of its development
As VivaCore library has been developed as part of Viva64 project it was reflected in some peculiarities of
its implementation. These peculiarities are:
1. Accurate diagnosis of syntax errors in program text was sacrificed to the ability of processing as
much code as possible. In case of parsing of code with the purpose to perform its static analysis
or some other processing (for example, coloring) it is more important to process as much text as
possible ignoring errors met. To detect syntax errors a compiler is used. VivaCore library
supposes that the code is correct. If it is not, it tries to ignore an incorrect section and starts
parsing at the next correct construction. It is useful if the code is incomplete or contains new
unknown key words or too complex constructions based on generic classes. However, nothing
prevents the user from inserting corresponding processors of incorrect input data.
2. Garbage Collector mechanism is not implemented in OpenC++. VivaCore library has the same
problem. As the result, while working VivaCore is constantly allocating memory without
returning it. It is not critically for Viva64 analyzer because it is launched for each file separately.
If a developer needs to work with the library for a long time, he will have to implement the
missing functionality.
3. The library is optimized for working on 64-bit systems.
4. There is no integral documentation. However, it is absent in OpenC++ as well. That's why
developers must be ready to spend some time on mastering it. Contact us if you have any
questions. We'll try to help you.
5. The library contains some functions which don't take part in the very code parsing but are
necessary for Viva64 and VivaMP projects.

7. Conclusion
I hope this article will help you to decide whether you should use VivaCore library in your projects. If you
are not sure - write. We'll try to provide you with additional information and answer your questions.
References
1. Andrey Karpov, Evgeniy Ryzhkov. The essence of the code analysis library VivaCore.
http://www.viva64.com/art-2-2-449187005.html
2. Evgeniy Ryzhkov. Viva64: working up of 64-bit applications.
3. http://www.viva64.com/art-1-2-206176447.html
4. Andrey Karpov. Description of VivaVisualCode. http://www.viva64.com/art-2-2-
1281792295.html