Earlier projects were part of work for the company (mostly Tektronix) but there are also a number of opensource projects that I had started privately or based on a university task. The sourcecode for the latter are freely available on the internet.

SMACS - Schema Mapping Application Compiler System

This compiler system is part of my master thesis which reads a set of transformation rules in a SQL-like language. As a result it generates program sourcecode that can be compiled into an application which will effectivly convert a database by reading entries from a database and writing converted values to a database with a different structure. The generator can optionally create sourcecode as a PL/SQL script in the different dialects of Oracle or Postgres, or otherwise it can create a Java Application with embedded JDBC access portions. The compiler itself is being written in Java with some JavaCC portions totaling to a medium size project of some fivehundred class definitions.

PFE - Portable Forth Environment

The protocol simulation environment of Tektronix measurement systems did require an engine that was capable of running all of the Forth scripts that had been developed in the decades before but this time doing telecom protocol testing on modern hardware. Other than the original series the new hardware generation was a lot more diverse including embedded boards of a different make up to virtual execution on a server system. The new system was supposed to be fully Standard ANS Forth compatible to allow ongoing transformation of older code to a contemporary level. The Forth system itself is written in portable C and additionally it can take advantage of GCC extras and assembly snippets for some targets. The derivate of this Forth engine at Tektronix is supporting about a thousand five hundred user commands.

AC-Archive - Autoconf Macro Archive

While working on numerous opensource projects I did create a larger set of Autoconf macros which are in themselves a series of unixshell commands embedded into macro directives of the m4 macro processor. My own set of macros grew with contributions that were sent by other Autoconf developers so that I bundled them into a public archive. The archive is being presented on the web in the AC Archive at Sourceforge. At the moment it does contain more than three hundred AC macros rendered through a Perl script into HTML and Docbook XML.

AST/TA - XML/DB

In the course of my student thesis I came to work on the XEE project of the local university being a C++ implementation of a new approach to XML databases. The underlying XML/TA model does store the XML nodes in an optimized disk tree structure separated from the text content. The text content can be stored linear (without interpersed markup) on disk which makes it easier accessible for classic text retrieval operations. While the XEE was targeting databases in the size of terabytes I was creating my own offspring project working in main memory. This XML/g project was written in C/glib as an engine for a documentation processor that is supposedly faster than any other in the field.

ZZipLib - a ZIP file system layer

The ZZipLib project is perhaps the most well-known of my opensource projects as it is the layer behind the PHP ZIP module which in turn allows to store compressed documents in ZIP-type archives on the server. Later some similar ZIP-based file system layers have become standard in webserver frameworks to bundle a number of small files into a common container. The DLL is implement in portable C matching the style of a posix file system. The obfuscation extension is quite popular among game developers to store and ship game data (artwork) files now.