Server(poller)-Client(pollSwayer) application for vote counting
Assignment 2 for Κ24 - System-Programming Semester 2022 - 2023

Author: sdi2000064 - Konstantinos Kanellakis

Summary

This project implements a server-client application for conducting a pre-election poll. The server, called poller, listens for client connections, receives votes, and stores them in a log file. The client, called pollSwayer, reads a list of voter names and votes from an input file and sends them to the server.

How to Run the Application

1. Compilation/Execution:

   • Compile the server (poller) and client (pollSwayer) applications using the following command:

     make all
     

   • Run the server (poller) with the following command:

     ./poller [portnum] [numWorkerthreads] [bufferSize] [poll-log] [poll-stats]
     

   • Run the client (pollSwayer) with the following command:

     ./pollSwayer [serverName] [portNum] [inputFile.txt]
     

2. Scripts:

   • Use the following scripts for various tasks:
     • create_input.sh: Generates an input file with random voter names and votes.

       ./create_input.sh politicalParties.txt numLines
       

     • tallyVotes.sh: Counts the number of votes each party received from the input file.

       ./tallyVotes.sh inputFile
       

     • processLogFile.sh: Counts the number of votes for each party from the poll-log file.

       ./processLogFile.sh poll-log
       

3. Checking Results:

   • To check if the poller and tallyVotes results match, run the following commands:

     cmp pollerResultsFile tallyResultsFile
     sort -o poll-stats poll-stats
     cmp tallyResultsFile poll-stats
     

Programming Design Choices - Server (poller)

• The server implementation utilizes multiple threads and synchronization mechanisms such as mutexes and condition variables.
• The main thread accepts client connections and places them in a buffer for worker threads to handle.
• Worker threads read requests from the clients, record votes, and update the log and stats files.
• The server ensures synchronization between the master thread and worker threads using condition variables and mutexes.

Programming Design Choices - Client (pollSwayer)

• The client application creates a thread for each line in the input file.
• Each thread connects to the server and sends the voter's name and vote.
• The client continues to read lines from the input file until all votes are sent.

Note

• The implementation does not have any memory leaks.
• The server runs until it receives a SIGINT (Ctrl+C) signal.
• The results are stored in the poll-stats file when the server terminates.

Purpose

The purpose of this assignment is to familiarize you with system programming in a Unix environment. It involves threading and network communication, specifically implementing a multithreaded server and a client application.

Problem 1: Multi-threaded network server

The server application, poller, runs a pre-election poll. It accepts connections from clients, receives votes, and stores them in log and stats files.

Problem 2: Batch client for testing purposes

The client application, pollSwayer, reads voter names and votes from an input file and sends them to the server for recording.

Problem 3: Bash scripts

Bash scripts are provided to assist in debugging the program and generating input files. These scripts include create_input.sh, tallyVotes.sh, and processLogFile.sh.

For more details on each problem and the implementation, please refer to the comments in the code files or send me a message.