Operating Systems Homework 4

Nehal Naeem Haji, nh07884

Overview

The deliverable of this assignment was a multi-threaded server in C, which takes the number of threads and the filename from the client (via the terminal) and sends a request to the server, through a TCP socket.

Principle of Action

1. Client Initialization:

   • The client program is started with the filename and the number of threads as command-line arguments.
   • The client establishes a connection to the server using a TCP socket.

2. Request Transmission:

   • The client sends the filename and the number of threads to the server.
   • The server receives the request and prepares to process the file.

3. File Splitting:

   • The server opens the requested file and calculates its size.
   • The server splits the file into chunks based on the number of threads specified by the client.

4. Thread Creation on Server:

   • The server creates multiple threads, each responsible for sending a chunk of the file to the client.
   • Each thread sends its assigned chunk to the client over a new socket connection.

5. Thread Creation on Client:

   • The client creates multiple threads, each responsible for receiving a chunk of the file from the server.
   • Each thread establishes a new socket connection to the server to receive its assigned chunk.

6. Data Transfer:

   • Each server thread sends its chunk of the file to the corresponding client thread.
   • Each client thread receives its chunk and writes it to a temporary file.

7. File Assembly:

   • After all chunks have been received, the client combines the temporary files into the final output file.
   • The client ensures that the chunks are combined in the correct order to reconstruct the original file.

8. Completion:

   • The client and server close their respective socket connections.
   • The client cleans up any temporary files created during the process.

How to run

Simply type make client to compile the client, and make server to compile the server. In order to get rid of the compiled files, including all object files, type make clean into the terminal.

To run all test cases, type ./tests.sh into the terminal. Note, you must give the script permission to execute by typing chmod +x tests.sh into the terminal.

Assumptions

The program assumes the files to be tested are already in the folder named test_files. If not, place them there before running the test script.

Limitations

• The server can only handle one client at a time.
• The maximum chunk size is 64KiB, meaning the server has to read the file in chunks of 64KiB.

Future work

A database server, such as MySQL or Microsoft SSMS, can be a future extension of this work.

Additionally, this server can be implemented across different machines on the same network.