= The VAMOS Project =

Topic of the project is variability of system software evoked by the
non-functional properties of operating-system functions, which emerges
from (a) different implementations of the same system function to make
an appearance of certain non-functional properties and (b) the using
level of those implementations in order to compensate for effects of
these properties.

With this project, the undertaker, we provide tools to examine and
evaluate CPP based source files. See
http://www4.informatik.uni-erlangen.de/Research/VAMOS/publications.shtml
for a list of publications.


For a up-to-date version of this document see

http://vamos.informatik.uni-erlangen.de/trac/undertaker/wiki

= undertaker =

The undertaker is an implementation of our preprocessor and
configuration analysis approaches. It can check the structure of your
preprocessor directives against different configuration models to find
blocks than can't be selected or deselected.

= Requirements =
 * libboost-wave (1.40 or above)
 * libboost-regex (1.40 or above)
 * libboost-filesystem (1.40 or above)
 * libboost (1.40 or above)
 * [http://check.sourceforge.net check] - testing suite for C
 * [http://fmv.jku.at/picosat/ picosat] (913-4 or above)

= Building = 
To install the dependencies in Debian or Ubuntu, you
paste this in your shell, but be aware that the picosat package in
Debian Lenny is far to outdated.

,----
| apt-get install libboost-wave1.40-dev libboost-regex1.40-dev libboost-filesystem1.40-dev \
|    libboost1.40-dev check picosat
`----


Compiling and installation

,----
|     $ make
| and
|     $ make install
| or  $ PREFIX=/path/to/install make install
`----


= Workflow (example) = 
To check a single file (or all files) in the
Linux kernel for dead or undead preprocessor blocks, you have to
extract the configuration models from the kconfig first. Therefore you
just have to execute undertaker-kconfigdump in the root of an Linux
tree. This will generate models for each architecture and place them
in the subfolder models.


,----[ $ ls models ]
| alpha.model  blackfin.model  h8300.model  m68k.model        mips.model     powerpc.model  sh.model     x86.model
| arm.model    cris.model      ia64.model   m68knommu.model   mn10300.model  s390.model     sparc.model  xtensa.model
| avr32.model  frv.model       m32r.model   microblaze.model  parisc.model   score.model    tile.model
`----


If you want to examine a single file for dead blocks with checks
against the models you can execute

,----[ $ undertaker -j dead -m models kernel/sched.c ]
| I: loaded rsf model for alpha
| [...]
| I: loaded rsf model for xtensa
| I: found 23 rsf models
| I: Using x86 as primary model
| I: creating kernel/sched.c.B250.x86.missing.dead
| I: creating kernel/sched.c.B360.x86.missing.dead
| I: creating kernel/sched.c.B362.x86.missing.dead
| I: creating kernel/sched.c.B364.missing.globally.dead
| I: creating kernel/sched.c.B368.x86.missing.dead
| I: creating kernel/sched.c.B396.x86.missing.dead
| I: creating kernel/sched.c.B408.x86.missing.dead
| I: creating kernel/sched.c.B421.x86.missing.dead
| I: creating kernel/sched.c.B437.x86.missing.dead
| I: creating kernel/sched.c.B447.missing.globally.dead
| I: creating kernel/sched.c.B556.x86.missing.dead
`----


This means in detail:
 * -j dead: do an dead analysis
 * -m models: load all models from directory models/
 * kernel/sched.c: examine this file

 * I: Using x86 as primary model": x86 is the default model which the
   file is checked against (this can be changed with -M <arch>) All
 * x86.missing.dead files are just dead on x86, there is at least one
   architecture this block can be enabled missing.globally.dead files
   are dead on every architecture.

To check all files in the Linux kernel there is the helper script
undertaker-linux-tree, which starts the undertaker with the correct
list of working files and gives it the correct count of parallel
worker processes on your multicore machine.


,----
| $ undertaker-linux-tree
`----