Assignment $2$: sed

For this assignment, you will use sed, bash, and some other command$-$line utilities to create a program

for formatting C code. Your program should take a source code file as input and apply the following:

$$ No more than one space between tokens.

$$ No trailing whitespace after a line.

$$ Binary operators should always surrounded by a single space on either side $($including assignment

and Boolean$).$ Only the following operators must be accounted for: $+,-,*,/,=,==,<=,>=,<,>.$

$$ Conditions should not have whitespace immediately inside of the parentheses.

$$ The program should not modify spaces which are leading, expanded tabs$.$

$$ Comments should be left alone. You may assume comments $($single$-$ and multi$-$line$)$ will not appear

on lines with source code.

Hint: The above need not be performed in a single pass.

This assignment requires only sed and bash. Do not use awk, Python, or any other languages, utilities,

or programs unless explicitly approved. The assignment is best solved using the specific topics discussed

in class and that you will find in the $$sed$$ slide deck.

Example

In the code below, underscores $(\_)$ represent spaces. Note that there are no changes to comments or

#include pre$-$processor directives. This file is merely an example; you should test your script against

input files you have formulated yourself, with the aim of developing test cases that cover as many

potential input types, groups, and values as possible.

Input $($inputProgram$.$c$)$:

$1/**$

$2$ author : $\_\_\_\_\_$som e$\_$stud ent

$3**/$

$4$ # include$\_<$ stdio $.$h $>$

$5$

$6$ int$\_$main $()\_\{$

$7\_\_\_\_$int$\_$numberIn ;

$8$

$9\_\_\_\_$printf $("$ Enter$\_$a$\_$number : $\_")$ ;

$10$

$11\_\_\_\_$scanf $("\%$ d $",\_$ & numberIn $)$ ; $\_\_$

$12$

$13\_\_\_\_$if$\_(\_$numberIn$\_>\_10\_)\_\{$

$14\_\_\_\_//\_\_\_\_$add$\_\_$two

$15\_\_\_\_\_\_\_\_$ r e t u r n $\_$ n u m b e r I n $\_+\_\_2$ ;

Assignment $2$: sed Page $1$ of $3$

$16\_\_\_\_\}\_$else$\_\_\_$if$\_\_\_\_($ numberIn $<5)\{$

$17\_\_\_\_//\_\_\_\_$ s ub t r ac t $\_$ tw o $\_\_\_$

$18\_\_\_\_\_\_\_\_$return$\_\_$numberIn$\_-\_2$ ;

$19$

$20\_\_\_\_$ r e t u r n $\_\_$ n u m b e r I n $*2$;

$21\}$

Output $($outputProgram$.$c$)$:

$1/**$

$2$ author : $\_\_\_\_\_$som e$\_$stud ent

$3**/$

$4$ # include$\_<$ stdio $.$h $>$

$5$

$6$ int$\_$main $()\_\{$

$7\_\_\_\_$int$\_$numberIn ;

$8$

$9\_\_\_\_$printf $("$ Enter$\_$a$\_$number : $\_")$ ;

$10$

$11\_\_\_\_$scanf $("\%$ d $",\_$ & numberIn $)$ ;

$12$

$13\_\_\_\_$if $($ numberIn$\_>\_10)\_\{$

$14\_\_\_\_//\_\_\_\_$add$\_\_$two

$15\_\_\_\_\_\_\_\_$ r e t u r n $\_$ n u m b e r I n $\_+\_2$ ;

$16\_\_\_\_\}\_$else$\_$if $($ numberIn$\_<\_5)\{$

$17\_\_\_\_//\_\_\_\_$ s ub t r ac t $\_$ tw o $\_\_\_$

$18\_\_\_\_\_\_\_\_$return$\_$numberIn$\_-\_2$ ;

$19$

$20\_\_\_\_$ r e t u r n $\_$ n u m b e r I n $\_*\_2$ ;

$21\}$

Script Execution

Your program should be invoked through a single bash file $($see below$)$ with the path to the input text file

specified as the first and only argument. The resulting output file should be printed directly to standard

out.

$ bash assign$2.$bash $/$path$/$to$/$input$/$file$.$txt

Assignment Data

Script Files

Your program should consist of at least two files:

$$ assign$2.$bash $$ the main file which is initially invoked

$$ At least one $.$sed file which is used for a sed invocation, run via assign$2.$bash. Each sed

invocation should have its own $.$sed file which may contain multiple sed commands.

For example, your submission may include assign$2.$bash, command$1.$sed, and command$2.$sed where

the two $.$sed files are used for two corresponding sed invocations within assign$2.$bash.