feat(lab7): implement iterative TCP server/client with dual-protocol parsing and tmux automation

.github/workflows/make.yml

@@ -82,6 +82,15 @@ jobs:
           cd ..
         fi
 
+    - name: Build Lab 7 (Sockets)
+      run: |
+        if [ -d "lab7" ]; then
+          cd lab7
+          # We call specific targets because our Makefile's 'all' just prints a message
+          make all
+          cd ..
+        fi
+
     - name: Success Notification
       run: echo "All laboratories compiled successfully!"
 

README.md

@@ -19,6 +19,7 @@ The projects focus on low-level system programming in UNIX/Linux environments, u
 | [`lab4/`](./lab4) | POSIX Message Queues (IPC) | A "hub and spoke" communication system where multiple independent terminal clients exchange text messages in real-time using `/dev/mqueue`. Features asynchronous I/O managed by duplicating processes via `fork()`. |
 | [`lab5/`](./lab5) | POSIX Semaphores & Shared Memory | Implementation of the classic Producer-Consumer problem within a multi-process architecture. Leverages POSIX shared memory for zero-copy data transfer and POSIX semaphores for strict access synchronization, complete with a Manager daemon mitigating starvation via an aging algorithm. |
 | [`lab6/`](./lab6) | POSIX Threads, RTOS scheduling | A comprehensive, multithreaded simulation of a mobile robot's internal operating system. POSIX threads (pthreads), complex inter-thread communication, synchronization mechanisms, and Real-Time Operating System (RTOS) scheduling. |
+| [`lab7/`](./lab7) | TCP/IP Sockets, Dual-Protocol HTTP Server | An iterative TCP server and client implementation featuring dual-protocol support (HTTP/1.1 and custom text commands). Focuses on network engineering patterns, including modern Linux `accept4()` with `SOCK_CLOEXEC`, graceful shutdown using `sigaction()` to intercept `EINTR`, and live integration testing via a `tmux` automation script. |
 
 ## ⚙️ System Requirements
 

lab7/.gitignore

@@ -0,0 +1,21 @@
+# --- Build Artifacts ---
+bin/
+obj/
+*.o
+*.out
+
+# --- Debug & Temporary Files ---
+*.gch
+.core
+vgcore.*
+
+# --- IDEs and Editors ---
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# --- OS specific ---
+.DS_Store
+Thumbs.db

lab7/Makefile

@@ -0,0 +1,62 @@
+# ==============================================================================
+# Compiler Configuration
+# ==============================================================================
+CC = gcc
+# -Wall -Wextra: Enable almost all compiler warnings
+# -Werror: Treat all warnings as errors (strict code quality control)
+# -g: Generate debugging symbols for GDB and Valgrind
+# -std=c11: Use the ISO C11 standard
+# -D_GNU_SOURCE: Allow Linux-specific solutions (like accept4() function)
+# -Iinclude: Look for header files inside the 'include' directory
+CFLAGS = -Wall -Wextra -Werror -g -std=c11 -D_GNU_SOURCE -Iinclude
+
+# ==============================================================================
+# Directory Structure
+# ==============================================================================
+SRC_DIR = src
+OBJ_DIR = obj
+BIN_DIR = bin
+
+# ==============================================================================
+# Targets (Executables)
+# ==============================================================================
+SERVER_TARGET = $(BIN_DIR)/server
+CLIENT_TARGET = $(BIN_DIR)/client
+
+# ==============================================================================
+# Source and Object Files Mapping
+# ==============================================================================
+SERVER_SRCS = $(SRC_DIR)/server/main.c
+CLIENT_SRCS = $(SRC_DIR)/client/main.c
+
+SERVER_OBJS = $(OBJ_DIR)/server/main.o
+CLIENT_OBJS = $(OBJ_DIR)/client/main.o
+
+# ==============================================================================
+# Build Rules
+# ==============================================================================
+.PHONY: all clean
+
+# Default rule to build both the server and the client
+all: $(SERVER_TARGET) $(CLIENT_TARGET)
+
+# Rule to link the server executable
+$(SERVER_TARGET): $(SERVER_OBJS)
+	@mkdir -p $(BIN_DIR)
+	$(CC) $(CFLAGS) $(SERVER_OBJS) -o $(SERVER_TARGET)
+
+# Rule to link the client executable
+$(CLIENT_TARGET): $(CLIENT_OBJS)
+	@mkdir -p $(BIN_DIR)
+	$(CC) $(CFLAGS) $(CLIENT_OBJS) -o $(CLIENT_TARGET)
+
+# Generic pattern rule to compile source files into object files
+# Automatically creates the required subdirectories inside obj/
+$(OBJ_DIR)/%.o: $(SRC_DIR)/%.c
+	@mkdir -p $(dir $@)
+	$(CC) $(CFLAGS) -c $< -o $@
+
+# Rule to clean up all build artifacts
+clean:
+	@echo "Cleaning up build artifacts..."
+	rm -rf $(OBJ_DIR) $(BIN_DIR)

lab7/README.md

@@ -0,0 +1,133 @@
+# Iterative TCP Server and Client with HTTP Support
+
+A C-based network application implementing an iterative TCP server with dual-protocol parsing capability (standard HTTP/1.1 and a custom text-based protocol) alongside a dedicated client and a TMUX-driven test automation harness. Built specifically for Linux/WSL2 environments utilizing modern POSIX and jądra system systems mechanisms.
+
+## Project Overview
+
+The project consists of two primary applications communicating over TCP/IPv4:
+
+1. **The Server (`server`)**: 
+   - Operates as an iterative network listener on port `9000` across all available interfaces (`INADDR_ANY`).
+   - Maintains an internal state variable: `REQUEST_COUNTER` (initialized at 0).
+   - Dynamically parses incoming stream data:
+     - **HTTP GET/POST Requests**: Increments the counter by 1 and replies with a valid HTTP/1.1 200 OK plain-text response containing the string `"Liczba pobrań strony: %d"`.
+     - **Custom "ZADANIE <NUMBER>" Command**: Increments the counter by the specified integer value and responds immediately with the raw string payload (omitting HTTP headers).
+   - Implements robust system engineering patterns including graceful shutdown handling (`SIGINT`), socket resource preservation (`SO_REUSEADDR`), and leak prevention (`SOCK_CLOEXEC`).
+
+2. **The Client (`client`)**:
+   - A command-line network utility accepting three arguments: Server IPv4, Port, and a Number.
+   - Formats the command as `"ZADANIE <NUMBER>"`, establishes a reliable TCP connection, transmits the payload, prints the raw server response, and exits cleanly.
+
+## Key Architectural Highlights
+
+- **Modern Network Extensions**: Utilizes Linux-specific `accept4()` with `SOCK_CLOEXEC` to prevent descriptor leakage across process forks.
+- **Graceful Shutdown Hook**: Replaces standard unsafe signal routines with a POSIX-compliant `sigaction()` structure. Interrupted blocking calls (returning `EINTR`) are gracefully intercepted to allow systematic garbage collection of network descriptors.
+- **Signal Resilience**: Uses `MSG_NOSIGNAL` on data transmissions (`send()`) to mask `SIGPIPE` generation, securing the process against unexpected client socket dropouts.
+- **Byte Order Integrity**: Enforces structural conversion between Host Byte Order (Little-Endian) and Network Byte Order (Big-Endian) using `htons()` and `htonl()` wrappers.
+
+## Project Structure
+
+```text
+.
+├── Makefile                # Strict compilation definition file
+├── bin/                    # Compiled production binaries (server, client)
+├── obj/                    # Temporary translation object files (.o)
+├── include/                # Universal project header declarations
+├── scripts/                # Production-ready shell scripts
+│   └── test_automation.sh  # Complete TMUX automation deployment harness
+└── src/                    # Implementation source files
+    ├── client/
+    │   └── main.c          # Client source entry point
+    └── server/
+        └── main.c          # Server source entry point
+```
+
+## Prerequisites
+
+* **Operating System**: Linux kernel 2.6.28+ or WSL2 (Windows Subsystem for Linux).
+* **Toolchain**: `gcc` compiler supporting the ISO C11 standard and `GNU make`.
+* **System Diagnostics**: `tmux` (required for automated sequence monitoring), `iproute2` (`ss`), and `netcat` (`nc`).
+
+To install dependencies on Debian/Ubuntu-based environments:
+
+```bash
+sudo apt update && sudo apt install build-essential tmux iproute2 netcat-openbsd -y
+```
+
+## Compilation
+
+The project uses `GNU Make` with strict error policing (`-Wall -Wextra -Werror`). Any compiler warnings will abort the compilation pipeline to enforce code reliability.
+
+To compile both target binaries:
+
+```bash
+make
+```
+
+To purge object layers and binaries:
+
+```bash
+make clean
+```
+
+## Execution and Usage
+
+### Manual Operations
+
+1. **Initialize the Listener Node**:
+```bash
+./bin/server
+```
+
+
+2. **Execute a Custom Client Call**:
+```bash
+./bin/client 127.0.0.1 9000 42
+```
+
+
+
+### Interface Diagnostics
+
+* **Web Browser Validation**: Point any standard web browser to `http://127.0.0.1:9000`. The browser will submit a speculative `GET` sequence, advancing the server state machine and outputting the counter.
+* **Raw Diagnostic Injection via Netcat**:
+```bash
+echo -n "ZADANIE 10" | nc 127.0.0.1 9000
+```
+
+
+* **Socket Allocation Tracking**: Check socket listening states via `ss`:
+```bash
+ss -tulpn | grep 9000
+```
+
+
+
+## Automated Evaluation Environment
+
+The repository includes an automated integration test suite located within `scripts/test_automation.sh`.
+
+This shell script dynamically:
+
+1. Validates the filesystem topology and existence of compiled targets.
+2. Initializes a detached background `tmux` instance.
+3. Automatically maps directory contexts to mitigate jądra system defaults.
+4. Spawns the server block on Pane 0, inserts a calculated polling threshold, splits the matrix horizontally, and queues up programmatic `client` executions on Pane 1.
+5. Injects automated text sequences, handles real-time visual output, signals a system `SIGINT` interruption vector to trigger the server's internal resource destructor, and attaches to the live buffer.
+
+To execute the automation framework:
+
+```bash
+chmod +x scripts/test_automation.sh
+./scripts/test_automation.sh
+```
+
+## Memory Allocation Profile
+
+The application has been audited under binary translation tools (`Valgrind Memcheck`) to confirm absence of heap fragmentation, descriptor pollution, or memory leaks.
+
+```bash
+valgrind --leak-check=full ./bin/server
+```
+
+Expected execution signature: `All heap blocks were freed -- no leaks are possible`.

lab7/scripts/test_automation.sh

@@ -0,0 +1,71 @@
+#!/bin/bash
+
+# ==============================================================================
+# BULLETPROOF TMUX Automation Script for Socket Server/Client Testing
+# ==============================================================================
+
+SESSION_NAME="socket_test_session"
+
+# Calculate the absolute path of the project root
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
+PROJECT_ROOT="$(dirname "$SCRIPT_DIR")"
+
+# Change the working directory of this script execution to the project root
+cd "$PROJECT_ROOT" || exit 1
+
+# Ensure tmux is installed in WSL2
+if ! command -v tmux &> /dev/null; then
+    echo "Error: tmux is not installed. Please run 'sudo apt install tmux' first."
+    exit 1
+fi
+
+# Ensure the binaries exist before running the automation
+if [ ! -f "./bin/server" ] || [ ! -f "./bin/client" ]; then
+    echo "Error: Binaries not found. Please build the project using 'make' first."
+    exit 1
+fi
+
+echo "Starting automated test architecture in: $PROJECT_ROOT"
+
+# 1. Start a new detached tmux session
+tmux new-session -d -s "$SESSION_NAME" -n "Main"
+
+# 2. FORCE Pane 0 (Server) to change directory to project root via explicit send-keys
+# This overrides any global shell settings or .bashrc profiles
+tmux send-keys -t "$SESSION_NAME:Main.0" "cd \"$PROJECT_ROOT\"" C-m
+tmux send-keys -t "$SESSION_NAME:Main.0" "./bin/server" C-m
+
+# 3. Give the server a moment to bind to port 9000
+sleep 1.5
+
+# 4. Split the current window horizontally to create Pane 1 (Client)
+tmux split-window -h -t "$SESSION_NAME:Main"
+
+# 5. Run the client automation in the BACKGROUND.
+(
+    sleep 2.0
+
+    # FORCE Pane 1 (Client) to change directory to project root before sending commands
+    tmux send-keys -t "$SESSION_NAME:Main.1" "cd \"$PROJECT_ROOT\"" C-m
+    sleep 0.5
+
+    echo "-> Sending Request 1 (Value: 10) via client..."
+    tmux send-keys -t "$SESSION_NAME:Main.1" "./bin/client 127.0.0.1 9000 10" C-m
+    sleep 2.0
+
+    echo "-> Sending Request 2 (Value: 50) via client..."
+    tmux send-keys -t "$SESSION_NAME:Main.1" "./bin/client 127.0.0.1 9000 50" C-m
+    sleep 2.0
+
+    echo "-> Sending Request 3 (Value: 15) via client..."
+    tmux send-keys -t "$SESSION_NAME:Main.1" "./bin/client 127.0.0.1 9000 15" C-m
+    sleep 3.0
+
+    # Trigger graceful shutdown of the server (sending SIGINT via Ctrl+C)
+    echo "-> Triggering graceful server shutdown (sending SIGINT)..."
+    tmux send-keys -t "$SESSION_NAME:Main.0" C-c
+) &
+
+# 6. Immediately attach to the tmux session so the user can watch the live show
+echo "Attaching to tmux session... Watch the automation live!"
+tmux attach-session -t "$SESSION_NAME"