Custom HTTP Server in C

Overview

This project implements a custom HTTP server using C, designed to handle simple HTTP requests such as serving static files, echoing back parts of the URL, and handling user-agent queries. This server is built using basic socket programming and is intended as a learning tool or a simple, lightweight HTTP server for specific use cases.

Features

Serving static files: Handles GET requests to serve files from a specified directory.
Echo service: Echoes back the text provided in the URL.
User-Agent handling: Responds with the User-Agent header sent by the client.
Basic error handling: Returns appropriate HTTP status codes for various errors (e.g., 404 Not Found, 500 Internal Server Error).

Building the Server

Prerequisites

A C compiler (e.g., gcc)
Basic knowledge of socket programming in C

Instructions

Clone the repository (if applicable):

git clone <repository_url>
cd <repository_directory>

Compile the server:
```
gcc -o http_server http_server.c
```
Run the server:
```
./http_server --directory <directory_path>
```
Replace <directory_path> with the path to the directory you want to serve files from.

Code Explanation

Argument Parsing

The parse_args function uses getopt_long to parse command-line arguments. It requires a --directory argument to specify the directory to serve files from.

Main Function

Socket creation:

server_fd = socket(AF_INET, SOCK_STREAM, 0);

Set socket options:

setsockopt(server_fd, SOL_SOCKET, SO_REUSEPORT, &reuse, sizeof(reuse));

Bind the socket to a port:

bind(server_fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));

Listen for incoming connections:
```
listen(server_fd, connection_backlog);
```
Accept and handle connections: The server uses accept to wait for incoming connections. For each connection, it forks a new process to handle the request. The child process handles the request and sends a response back to the client.

Request Handling

Root (/): Responds with a simple message.
Echo (/echo/): Echoes back the part of the URL following /echo/.
Files (/files/):
- GET: Reads and serves the requested file from the specified directory.
- POST: Writes the request body to the specified file in the directory.
User-Agent: Parses the headers to find and respond with the User-Agent header.

Error Handling

Appropriate HTTP status codes and messages are returned for various error conditions, such as file not found or internal server errors.

Contributing

If you wish to contribute to this project:

Fork the repository.
Create a new branch for your feature or bugfix:
```
git checkout -b feature-name
```
Make your changes.
Commit your changes:
```
git commit -m "Description of changes"
```
Push to the branch:
```
git push origin feature-name
```
Create a pull request.

Please ensure your code follows the existing style and includes comments where necessary. Contributions are welcome, especially in the areas of improving functionality, fixing bugs, and enhancing documentation.

oyejateen/server-in-c