Introduction

cppstats is a tool for analyzing software systems regarding their variability. Therefore, we focus on software systems written in C using the capabilities of the cpp (The C preprocessor) to express variability.

Basic work

C source		xml representation
	⇔

Data about the cpp

The project statement is to get information about the usage of the cpp in C software projects. Apart from the quantity of cpp usage within software projects, more information about, where the preprocessor is used and what is the extension that cpp annotations are enframing. This leads to the question of granularity of cpp within software projects.

We have developed a tool, called cppstats to analyze 40 public available open source projects from different domains including compilers, database management systems, operating systems, and application software. The following table contains (1) the names of all analyzed software systems, (2) its version (development versions with date of download in brackets), (3) the domain the software refers to, and (4) the output of the analysis as CSV file.

number	software system	version	domain	data
01	apache	2.2.11	Web server	apache.csv
02	berkeley db	4.7.25	database system	berkeley.csv
03	cherokee	0.99.11	Web server	cherokee.csv
04	clamav	0.94.2	antivirus program	clamav.csv
05	dia	0.96.1	diagramming software	dia.csv
06	emacs	22.3	text editor	emacs.csv
07	freebsd	7.1	operating system	freebsd.csv
08	gcc	4.3.3	compiler framework	gcc.csv
09	ghostscript	8.62.0	postscript/pdf interpreter	ghostscript
10	gimp	2.6.4	graphics editor	gimp.csv
11	glibc	2.9	programming library	glibc.csv
12	gnumeric	1.9.5	spreadsheet appl.	gnumeric.csv
13	gnuplot	4.2.5	plotting tool	gnuplot.csv
14	irssi	0.8.13	IRC client	irssi.csv
15	libxml2	2.7.3	XML library	libxml2.csv
16	lighttpd	1.4.22	Web server	lighttpd.csv
17	linux	2.6.28.7	operating system	linux.csv
18	lynx	2.8.6	Web browser	lynx.csv
19	minix	3.1.1	operating system	minix.csv
20	mplayer	1.0rc2	media player	mplayer.csv
21	mpsolve	2.2	mathematical software	mpsolve.csv
22	openldap	2.4.16	LDAP directory service	openldap.csv
23	opensolaris	(2009-05-08)	operating system	solaris.csv
24	openvpn	2.0.9	security application	openvpn.csv
25	parrot	0.9.1	virtual machine	parrot.csv
26	php	5.2.8	programming language	php.csv
27	pidgin	2.4.0	instant messenger	pidgin.csv
28	postgresql	(2009-05-08)	database system	postgresql.csv
29	privoxy	3.0.12	proxy server	privoxy.csv
30	python	2.6.1	programming language	python.csv
31	sendmail	8.14.2	mail transfer agent	sendmail.csv
32	sqlite	3.6.10	database system	sqlite.csv
33	subversion	1.5.1	revision control system	subversion.csv
34	sylpheed	2.6.0	e-mail client	sylpheed.csv
35	tcl	8.5.7	programming language	tcl.csv
36	vim	7.2	text editor	vim.csv
37	xfig	3.2.5	vector graphics editor	xfig.csv
38	xine-lib	1.1.16.2	media library	xine.csv
39	xorg-server	1.5.1	X server	xorg.csv
40	xterm	2.4.3	terminal emulator	xterm.csv

HowTo

Prerequisites

cppstats is written in Python and relies on certain libraries and other tools in order to work. It has been tested with Python (version 2.5.2) and runs on Linux-based systems.

• python-lxml (python binding to libxml2 and libxslt; python-lxml download)
• astyle (source code indention and reformatting filter; astyle download)
• xsltproc (command line XSLT processor; xsltproc download)
• cpp (The C preprocessor, as a part of the compiler-suite gcc; cpp download)

After installing all the programs and libraries cppstats relies on, download cppstats from here and unzip the archive. An example of the invokation of the tool is given below. Get a C software program of Your choice and download it. Unpack the sources and apply the cppstats analyzer.

Typical workflow:

# select all projects that should be analyzed by editing the cppstats_input.txt
# note, the project selected in cppstats_input.txt should have the following form:
# project-folder/
#             -> source
# cppstats_input.txt contains all absolute paths to the project-folders
	vim cppstats_input.txt

# for a general analysis run following scripts; see ICSE 2010 paper
	./cppstats_general_prepareall.sh
	./cppstats_general_checkall.sh

# for discipline analysis run following scripts; see AOSD 2011 paper
	./cppstats_dmacros_prepareall.sh
	./cppstats_dmacros_checkall.sh
	

After a successful analysis a csv-file (cppstats.csv) with the results can be found in the _cppstats subfolder of the given folder parameter (ICSE 2010) or the txt-file (disciplined_stats.txt) in the cppstats folder (AOSD 2011).

Downloads

• We enhanced cppstats for another study. Further information and the enhanced tool are available on the supplementary website.
• cppstats is also available on github -- github: project website
• Version 0.7 -- Sources: cppstats_0.7.zip
• Version 0.5 -- Sources: cppstats_0.5.zip
• Version 0.4 -- Sources: cppstats_0.4.zip
• Version 0.3 -- Sources: cppstats_0.3.zip (includes the script dmacros.py for analyzing the discipline of ifdef annotations
• Condensed data of the analysis regarding the discipline of preprocessor usage: ifdef_discipline.csv
• Version 0.2 -- Sources: cppstats_0.2.zip
• Version 0.1 -- Sources: cppstats_0.1.zip

Examples

• A variable list implementation in C -- Sources: sortedlist.c
• Manual and automated expansion of ill-formed or undisciplined annotations: manual_autmated_expansion.tar.gz

C grammar

• BNF-like C grammar for YACC -- Sources: c.html

Contact

cppstats has been developed at the University of Passau, Germany cppstats project, please contact the developer:

• Jörg Liebig (University of Passau, Germany)