CPE 101
Spring 2007
Laboratory 10
Due Date
Friday 8 June 5:00pm
You must turn in your source electronically on hornet using the
handin command – instructions are provided below.
Objectives
- To practice creating and using records (structs) in C.
- To practice using and creating arrays of records.
- To practice using FILE I/O.
- To practice developing functions to work with array data.
- To practice writing functions with output parameters (using
pointers).
Resources
- Your instructor, peers, texts, and your own innate capabilities
and resourcefulness!
- A skeleton, lab10skeleton.c, to start
from that contains three complete functions. Rename this file to
lab10.c.
Orientation...
This lab will involve developing a small C program which handles data
about a running "log book". You will be creating your own record type
in order to store the run information used by the
running log. You will need to develop a variety of functions to
process this data. (Note that part of this lab is intended to
help
you practice using output parameters (pointers), so all of your
functions should be void functions.) Read this entire lab before
you begin working.
Part 0: Creating the data type and
reading in data...
Start out by defining a record to
store run data. This record must be named
run_t and
must include:
- The name of the run (20 character maximum)
- The distance of the run in miles
- The PR (personal record) for the run in seconds.
- The number of times the run has been done.
The lab10skeleton.c file should compile once you define your
run_t struct.
You will also be writing a variety of functions which operate on the
run data. You will read an initial 'run' database from file,
however, every time the user goes for a run, the program data must
change to reflect this. The run database will hold at most 30
different runs.
Write a function
readFile to read the run data
from an input file named
run.data
and store it in your internal data
structure. This function must populate your array of runs and
return the number of runs read from the file (either via the return
value or an output parameter). You must develop this entire
function yourself. You are not given a prototype to work from.
Note that the strings representing
the run names have
underscores instead of spaces in them. This program will
be much
more difficult if you try to implement it with strings that have spaces
in them. Use an underscore whenever you mean to put a
space in the run name.
good: los_osos_loop
bad: los osos loop
Write a funcion to print out the run data. The print function
should use the PR seconds to print the PR time in hours, minutes, and
seconds. Additionally, it should use the PR seconds and distance
to compute the PR mile pace. (Note that the pace does not print
hours because it is highly unusual for a runner to take a runner longer
than 59 minutes to run a mile.) The initial input should print
out as follows:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 7
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:42:30 9:26
3
Remember to make this a void function. Tip: a placeholder of "%02d"
will place leading zeroes in a field of width 2.
void
displayRuns(const run_t list[], /* input
- run list
*/
int numRuns); /* input - number of runs in the list */
In order to
print the PR and Pace, you need to use a function that will
convert seconds to hours, minutes, and seconds. The function
takes the total seconds as an input paramenter and hours,
minutes, and seconds as output paramters. This function is written for you.
void
secsToHMS(int totalSecs, /* input - total seconds */
int *h, /* output - hours */
int *m, /* output - minutes */
int *s); /* output - seconds */
Part 2: Creating a function to add a
run to the list...
Next you will be writing a function to edit the run list. There
are two possible ways to edit the list. Either the user will add
a new run to the list or update an existing run.
void
addRun(run_t list[], /* input - run
list
*/
int
*numRuns); /* input/output - number of runs in the list */
First, prompt the user for the name of the run. Then call a
function findRun
to determine if the run is already in the database:
It takes as input the array of run data, the current number of
runs
in the list, and the run to search for as input parameters. It
takes the index location were the run
is found as an output parameter. The function sets the index to
the position in
the list of the target run or a -1 if the run is not found. This function is written for you.
void
findRun(const run_t r[], /* input - run list */
int numRuns, /* input - number of runs in the list */
const char name[], /* input - run to search for */
int *index); /* output - position of found run */
If the run is
not in the list...
- Set the name of the run in the next available spot in the list.
- Get the distance in miles.
- Get the time the user took to do the run in hours, minutes, and
seconds. Convert that to seconds and set the PR seconds for the
run. Note that whatever time the user enters will be the PR since
it is the first time the run is done.
- Set the count for the run to one.
- Increment the number of runs in the list.
If the run exists in the list...
- Prompt the user for the time it took for them to complete the
run. Check to see if this time is less than the PR time and
update the PR accordingly.
- Increment the count for the current run. (Do not increment
the number of runs in the list since no new run was added.)
Each time the database is updated, please print it out again.
A database is useless if the data is
not saved between runs of the program. You will call a function
to write
the run list out to the run.data
file before the user quits the program. This function is written for you.
void
writeFile(const run_t
list[], /* input - run list */
int numRuns); /* input - number of runs in the list */
Part 4: Create a main function to
drive your program...
Create a main function to orchestrate how your program runs. It
would be useful to work on this function as you write the above
functions to test your work.
Using the functions above, this function should...
- declare the array of runs to hold the run list,
- read the data from the file into the array,
- display the intial run list,
- in a loop, prompt the user for whether they would like to add a
run or quit,
- write the data to a file if the user chooses to quit and display "Happy trails!"
The following is an example run. The user input is in bold for
illustration only. Also note that the % sign is an example prompt
on hornet. Do not print the %.
% a.out
Run Report:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 7
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:42:30 9:26
3
(a)dd run or (q)uit: a
Run Name: calpoly
Time (hh mm ss): 1 10 45
Run Report:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 8
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:42:30 9:26
3
(a)dd run or (q)uit: a
Run Name: los_osos_loop
Time (hh mm ss): 0 41 23
Run Report:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 8
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:41:23 9:11
4
(a)dd run or (q)uit: a
Run Name: dog_park
Distance in Miles: 2.3
Time (hh mm ss): 0 22 10
Run Report:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 8
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:41:23 9:11
4
dog_park
2.30 0:22:10 9:38
1
(a)dd run or (q)uit: q
Happy trails!
% a.out
Run Report:
Name
Distance PR
Pace Count
------------------------------------------------------
diablo_loop
1.00 0:08:52 8:52 12
calpoly
6.20 1:07:30 10:53 8
prefumo_canyon
11.40 1:55:45 10:09 2
los_osos_loop
4.50 0:41:23 9:11
4
dog_park
2.30 0:22:10 9:38
1
(a)dd run or (q)uit: q
Happy trails!
%
1. Transfer
the source code file lab10.c to hornet as you’ve done for
previous labs.
2.
Log on to hornet using the Secure Shell Client program
(or your favorite equivalent).
3.
Change directory (cd-command)
to the directory containing the source file or files to hand in.
4.
Execute the following command – be sure to replace
the x in cs101-x with your section number:
handin cs101-x lab10 lab10.c
5.
You should see messages that indicate handin occurred without error. You can
(and should) always verify what has been handed in by executing the
following command:
handin cs101-x lab10