CProjects - six short assignments to be implemented in the C programming language
CSSE 221 – Fundamentals of Software Development Honors
Fall 2008–2009

Work on these exercises individually, but be quick to get help as needed from your student assistants, your instructor and your classmates.

CProject: Dog (structures)

Overview

This project introduces you to structures. Key ideas include:

• Use a typedef to define a structure type.
• Throughout, use pointers to structure objects rather than structure objects themselves. Following this Java style will keep you out of trouble.
• Don't forget to malloc space for pointers to point to, much as new does in Java.
• Don't forget to free previously malloc'ed space when it is no longer needed. Unlike Java, you cannot rely on a garbage collecter.

Instructions

1. Construct new CProject that is an ANSI C Project called Dog.
2. Add a new Header File to the src folder, choosing the "Default C header template" (not the C++ one) and calling the file Dog.h.
3. #include "Dog.h" in Dog.c.
4. In Dog.h, define a structure called Dog that has the following fields:

   • A name that is a C-style string of at most 6 characters.
   • A breed that is a C-style string of unlimited length.
   • An owner that is a C-style string of unlimited length.
   • An age that is an integer.
   • A weight that is a float.

5. In function main, declare a pointer to a Dog.
6. Get your work so far graded, by your instructor, student assistant or a newly-promoted student assistant.
• The grader should refer to the written answer key.
7. Write and test the following pair of functions (put their prototypes in Dog.h):

   • constructDog

     • It takes an age, allocates space for a Dog, sets the allocated Dog's age to the given age, and returns a pointer to the allocated Dog space.
     • Ignore the other fields of Dog for now.

   • printDog

     • It takes a pointer to a Dog and prints the dog's age.
     • Ignore the other fields of Dog for now.

8. Extend your pair of functions to deal with the following (write and test them one by one, in the order listed):

   • weight

   • name

   • breed

   • owner

   Assume (i.e. do NOT check) that the string arguments to constructDog are valid C-style strings. Also assume that the argument passed for the name is at most 6 characters. However, you must allow the breed and owner arguments to be strings of any length.

9. Get your work so far graded, by your instructor, student assistant or a newly-promoted student assistant.

• The grader should refer to the written answer key.
• With the grader, try passing in strings of length 7, 8, 9 and 20 for the dog's name.
  • For some of these, the run should execute as if nothing was wrong.
  • For others of these, you should see spurious characters.
  • Worse still, you should sometimes see unrelated variables modified by the buffer overflow.

10. Write a destructDog function that takes a Dog pointer and deallocates space for that Dog, including the malloc'ed space for its fields.
11. Get your work so far graded, by your instructor, student assistant or a newly-promoted student assistant.
    • The grader should refer to the written answer key.
12. Turn in your work by adding and committing your project to your individual repository.