Hammer Shell

Authors: Justin Schopick and Neal Goyal

Project Description

This program will mimic a linux or unix terminal. The program will run by allowing the user to take in a command. The program will parse each command into different vectors based on commands and connectors. Then, we use system calls to give each command functionality. For example:

 $ ls -a
 $ echo hello
 $ mkdir test

Is Equal To

 $ ls -a; echo hello; mkdir test

Requirements

Need to install the boost library to run the program. To get instructions on how to install, follow the website here. Also, you need to compile using C++11. In order to compile, you can either run our makefile or use the command

  $ g++ *.cpp -std=c++11

Features

• "||" executes the next command if the previous command fails.
• "&&" executes the next command if the previous command succeeds.
• ";" always executes the next command.
• "#" turns everything following it into a comment.
• "<" Has a command read in input from a file instead of the command prompt.
• ">" Outputs the result of a command into a file instead of the command prompt(replaces file contents).
• ">>" Appends the result of a command into a file instead of the command prompt.
• "|" Takes the output from a command and reads it in as input for the command on the other side of the pipe.

The test command can be executed using "test" or "[]". This will print (True) if the input exists and (False) if it does not exist. The following flags can be specified for the Test Command:

• No flag: treat as if -e flag.
• -e flag: test if the input is a directory or regular file.
• -d flag: test if the input is a directory.
• -f flag: test if the input is a regular file.

Scripts

In this lab, we used scripts to thoroughly test all the commands.

  single_command.sh        #tests single commands
  multi_command.sh         #tests commands with ;, &&, or ||
  commented_command.sh     #tests commands with comments
  test_test.sh             #tests the Test command
  precedence_test.sh       #tests if precedence is accounted for ()
  exit.sh                  #tests the Exit command
  input_redirect_test.sh   #tests input redirection (<)
  output_redirect_test.sh  #tests single output redirection (>)
  append_redirect_test.sh  #tests double output redirection (>>)
  pipe_test.sh             #tests piping (|)

Running RShell

$ git clone  https://github.com/nealgoyal/hammershell.git
$ cd hammershell
$ make
$ bin/rshell

Known Bugs

• We currently cannot account for non bin items, such as commands like "cd"
• Issues with shell scripts running accordingly to each test
• Cannot account for quotations within the commands
• Will run with a connector at the end of the program
• Cannot account for multiple parenthesis