This is the final assignment, worth 80% of the module marks, based on the attached archive FINAL-DISTR.zip
computer science
Description
Introduction
This is the final assignment, worth 80% of the module marks,
based on the attached archive FINAL-DISTR.zip
While an automated grading system will be used initially,
your code will be looked at, particularly
in the event of it giving really wrong answers or code failing to
compile. A failure of code to compile for any part below will cap the maximum
mark for that component to 39% of its full mark.
It has three parts, each of which can be done and assessed
independently of the others.
1.
An exercise using Promela/SPIN to model a
non-deterministic finite-state-automaton (NDFA)
2.
An exercise to add dynamic priority
(Linux-style) to the xv6 operating system.
3.
An exercise to add more levels of indirection to
file block access in xv6
Each is described in more detail below.
Part 1 (20% of overall)
Using Promela to model non-deterministic
finite-state-automatons was described in Lecture 16. In the archive you will
find the image for an example (EXAMPLE-NDFA.png) along with a PML file
(ndfa4.pml) that implements that example. This has added printf statements that
make its behaviour easier to observe. It has been setup to allow SPIN to search
for all possible accepting sequences of exactly length 4.
To do this search you need to do the following step: spin -run -E -c0 -e ndfa4.pml
This will generate a number of trail files, of which the nth
can be viewed using spin -tn ndfa4.pml. So, for example, the 3rd trail file can
be viewed using spin -t3 ndfa4.pml.
Task-1
Create a pml file called final.pml, that models the NDFA
shown in FINAL-NDFA.png, and that also can search for accepting sequences of
length less than or equal to 4.
Base your answer on ndfa4.pml, leaving lines 1..4 and 38..42
intact.
For submission for Part-1 :
final.pml
