CS 0449 – Project 1: Craps & ID3 Tags
Due: Sunday, February 5, 2012, at 11:59pm
Your first project is to write two programs in C that provide some experience with a wide range of the topics we have been discussing in class.
For the first part of this project, you will be implementing the game of Craps. For those unfamiliar with the rules, Craps is played with two dice which are rolled together. The sum of these two dice is computed and if the sum is:
· 2, 3, or 12 – the player immediately loses.
· 7 or 11 – the player immediately wins.
· Any other number is referred to as the “point.” The goal then becomes to keep rolling the dice until:
o The player rolls a 7 – the player loses
o The player rolls the “point” – the player wins.
Your job on this assignment is to make a simple craps game. In this game the
player will enter his or her name, the program will display a welcome message,
and ask if the player would like to play or quit. The program will then roll
two dice, and display them and their total. If the player has won, display a
message congratulating them. If the player has lost, report it to them.
Otherwise, store this first roll as the “point” roll and keep rolling until the
player wins or loses. When the game ends, ask if the player would like to play
again. Example:
Welcome to Jon’s Casino!
Please enter your name: Jonathan
Jonathan, would you like to Play or Quit? play
You have rolled 5 + 2 = 7
You Win!
Would you like to play again? no
Goodbye, Jonathan!
An ID3 version 1.1 tag for MP3s (and other multimedia files) adds metadata describing the file. The contents of an ID3 tag are the following:
Offset |
length |
description |
0 |
3 |
"TAG" identifier string |
3 |
30 |
Song title string |
33 |
30 |
Artist string |
63 |
30 |
Album string |
93 |
4 |
Year string |
97 |
28 |
Comment string |
125 |
1 |
A one-byte separator (always 0) |
126 |
1 |
Track number byte |
127 |
1 |
Genre identifier byte |
An ID3 (v1.1) tag like above is appended to a file as the last 128 bytes. The tag is present if at the -128 from end offset there are the three ASCII characters TAG.
For your project you will make a utility that can print the contents of an existing tag, if there, and add or modify a tag.
Make a program called id3tagEd and make it so that it runs with the following command line options:
id3tagEd FILENAME
should print the contents of the ID3 tag to the console if present, or give a message if not present
id3tagEd FILENAME -FIELD VALUE
should set the specified field to the value that follows it.
You should handle the following field names (specified in lowercase):
· Title
· Artist
· Album
· Year
· Comment
· Track
Make sure you are able to handle multiple {field, value} pairs on the command line at once. If the tag already exists in the specified file, then edit it, if not create a new tag by appending a tag at the end with the specified fields populated. Assume all others are to be empty (filled with 0 bytes.)
Ensure that your program builds on thot.cs.pitt.edu as that will be where we are testing.
If you are running low on AFS space, we’ve provided you a directory on the local harddrive at /u/SysLab/USERNAME where USERNAME is your Pitt user id. Note though that this directory is not backed up, so please save your work in AFS or somewhere else. Lost work due to machine failure is not grounds for an extension.
When you’re done, create a gzipped tarball (as we did in the first lab) of your commented source files and compiled executables and copy them to:
~jrmst106/submit/449/
Make sure you name the file with your username, and that you have your name in the comments of your source file. Please do NOT submit the sample music files we provide.
Note that this directory is insert-only, you may not delete or modify your submissions once in the directory. If you’ve made a mistake before the deadline, resubmit with a number suffix like abc123_1.tar.gz
The highest numbered file before the deadline will be the one that is graded, however for simplicity, please make sure you’ve done all the work and included all necessary files before you submit