© 2000, SUNY at Stony Brook
XMC is a model checker implemented using the XSB tabled logic programming system. XMC is an explicit-state, local model checker for processes specified in XL, a sugared version of value-passing CCS, and the alternation-free fragment of the modal mu-calculus. The XMC system is a result of the LMC (Logic-Programming-Based Model Checking) project at Stony Brook.
The LMC project is funded by a four-year grant from NSF's Experimental Software Systems (ESS) program. The project aims to combine the latest developments in concurrency research and in logic programming to advance the state-of-the art of system specification and verification. For more information on the LMC project, see http://www.cs.sunysb.edu/~lmc.
This is the first public release of XMC, dated April 2000. You may freely copy and distribute verbatim copies of the XMC system, provided this Readme.txt file is prominently placed in every copy. You may also modify any of the sources of the XMC system, and redistribute the modifications. However, (1) the modified sources must be freely available, under the same terms as the original XMC system; (2) the modified system should prominently state the complete revision history.
The software is provided "AS-IS" with NO WARRANTIES of any kind, express or implied including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the program is with you. Should the XMC system prove defective, you assume the cost of all necessary servicing, repair or correction.
In no event unless required by applicable law will SUNY at Stony Brook and/or any other party who may modify and redistribute XMC as permitted above, be liable to you for damages, including any lost profits, lost monies, or other special, incidental or consequential damages arising out of the use or inability to use (including but not limited to loss of data or data being rendered inaccurate or losses sustained by third parties or a failure of the program to operate with any other program) the program, even if you have been advised of the possibility of such damages, or for any claim by any other party.
For using XMC, the XSB system (version 2.0 or higher) must be installed first. XSB is a full-fledged Prolog system extended with tabled resolution, and is available for many platforms including Unix (SunOS, Solaris, HPUX, Linux, IRIX, etc.), Windows 95, and Windows NT. To obtain a free copy of XSB and associated documentation (including installation notes) see http://xsb.sourceforge.net.
The GUI components of the system are implemented in iTCL/Tk, which is avaliable from http://www.tcltk.com/itcl. The web site includes links to a source distribution and installation notes. This distribution of iTcl/Tk can be run on Unix systems, Windows 95/NT as well as Macintosh systems.
The XMC system release consists of source files and examples in tarred, compressed (gzip) form. Once unpacked, the XMC system will contain the following files and directories: GUI/ source programs for XMC user interface Examples/ a collection of example specifications Readme.txt plain-text version of this file System/ source programs for the XMC model checker install.sh installation script
XMC is implemented starting from a simple specification of the SOS semantics of CCS and modal mu-calculus as logic programs, (see files System/ccs.P and System/mucalculus.P). The syntactic sugar in the input specifications are stripped away and some preprocessing is performed by the XMC compiler "xlc". The file System/xmc.P contains the top-level code for the XMC system.
To install the XMC system, first unpack the tarball using
tar zxvf xmc.tar.gzor
gunzip -c xmc.tar.gz | tar xvf -This will create a directory xmc-1.0 which contains install.sh. Simply run ./install.sh to install the XMC system; the script will prompt you for 3 installation parameters:
The XMC system can now be started by using the shell script xmc in the bin directory. Any arguments used in the command line are passed to the XSB system. This can be used, for example, to set the default stack sizes of the XSB system. For instance: xmc -m 50000 makes the XSB system start with a global/local stack size of 50M. For other command line options of the XSB system, please see the XSB manual pages--- manual subdirectory of your XSB installation, or see XSB's online manual pages at http://xsb.sourceforge.net.
Once the XMC system is invoked, you will see a series of loader messages followed by a prompt ('| ?- '). From the prompt, you can compile and load XL specification files using xlc(_) command, or modelcheck using mck(_,_) command. The following is an example session for modelchecking the alternating bit protocol specification in Examples/ABP. [The commands typed by the user are underlined with ^^^ ; the rest are the responses of the XMC system].
$ xmc ^^^ [xsb_configuration loaded] [sysinitrc loaded] [packaging loaded] XSB Version 2.1 (Skol) of November 25, 1999 [sparc-sun-solaris2.6; mode: optimal; engine: chat; scheduling: batched] Evaluating command line goal: | ?- consult('/usr/pkg/XMC/System/xmc'). [xmc loaded] [mucalculus loaded] | ?- xlc(buggyabp). ^^^^^^^^^^^^^^ [/usr/pkg/XMC/System/stdtype.P dynamically loaded, cpu time used: 0.0190 seconds] [./buggyabp.xlo dynamically loaded, cpu time used: 0.0390 seconds] typechecking ... medium : $type(chan(_h766)) * $type(chan(_h766)) sender : $type(chan(_h872)) * $type(chan($type(integer))) * $type(integer) sendnew : $type(chan(_h656)) * $type(chan($type(integer))) * $type(integer) receiver : $type(chan($type(integer))) * $type(chan($type(integer))) * $type(integer) abp : [/usr/pkg/XMC/System/runlib.P dynamically loaded, cpu time used: 0.0190 seconds] yes | ?- mck(abp, drop_packet). ^^^^^^^^^^^^^^^^^^^^^^ ++Warning: Removing incomplete tables... yes | ?- halt. ^^^^^ End XSB (cputime 0.42 secs, elapsetime 28.70 secs) $For measuring the time taken to modelcheck or the space consumed, you can use XSB's builtin predicates cputime(_) and statisitics. Please see XSB manual for usage notes on these builtins.
Please send comments about the XMC system, suggestions for improvements, and bug reports to email@example.com.