SHA256-FIFO-Server

Small POSIX server/client project that computes the SHA-256 digest of files on request.

• Communication via named pipes (FIFOs)
• Server uses a master thread and a worker thread pool (pthreads)
• Duplicate requests for the same file are aggregated and served together
• Results are cached to avoid recomputation when the file has not changed
• Client sends a pathname and receives the SHA-256 hex string

Build

mkdir build && cd build
cmake ..
make

Requires OpenSSL development headers.

Usage

Start the server (creates /tmp/fifo_server_SHA256):

./server

In another shell run a client:

./client /path/to/file

The client creates a FIFO /tmp/fifo_client_SHA256.<PID> and receives a Response struct containing the hash (or an error code).

Example output

$ ./client test.bin
SHA-256(/home/user/test.bin) = 7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069

Files

• src/server.c — server implementation
• src/client.c — client implementation
• src/request_response.c — error helper
• src/errExit.c — error exit helper
• include/request_response.h — shared structs and error codes

Documentation

See docs/Architecture.md for details on design, synchronization, and caching.

License

This project is licensed under the MIT License — see the LICENSE file for details.