Compiler for a DSL for Hotel Reservations

Team implementation of a C compiler, using Flex and Bison tools, for hotel room reservations.

📖 Context

This project was developed for the Compilatori examination of Prof. Sabrina Mantaci, during the 2022/2023 Academic Year at the Università degli Studi di Palermo, Computer Science (L-31, 2086) course.

👥 Authors

Andrea Spinelli - Marco Valenti

🛠️ Technologies Used

• Languages: C
• Other: Git

🚀 Installation and Startup

To compile and run this project, you will need a C compiler and the standard compiler-construction tools.

Prerequisites

• A C compiler (e.g., GCC)
• Flex (Lexical Analyzer Generator)
• Bison (Parser Generator)
• make (Build Automation Tool)

Note: On Linux (like Ubuntu/Debian), you can install these tools with: sudo apt-get install build-essential flex bison. On macOS, these are included with the Xcode Command Line Tools. On Windows, you can use a toolchain like MinGW-w64 and install Flex/Bison for Windows.

Instructions

1. Clone the Repository Open your terminal and clone the repository to your local machine.

   git clone https://github.com/A-rgonaut/L-31_Compiler_for_a_DSL_for_Hotel_Reservations.git
   cd L-31_Compiler_for_a_DSL_for_Hotel_Reservations

2. Compile the Project Use the provided Makefile to build the compiler. This will generate the parser/scanner C files and compile all sources into a single executable.

   make

   This will create an executable file named HotelBookingCompiler in the root directory.

3. Run the Compiler The compiler takes one argument: the path to a source file written in the hotel booking DSL. You can use the provided test files to see it in action.

   # Run with the first test file
   ./HotelBookingCompiler test.txt
   
   # Run with the second test file
   ./HotelBookingCompiler test2.txt

4. How to Write Source Files You can create your own .txt files with commands for the compiler to execute. For example:

   # file: my_commands.txt
   
   LIST_ROOMS_AVAILABILITY 2024-12-25
   
   BOOK_ROOM 101 2024-12-24 2024-12-26 "Alice Smith"
   
   SHOW_RESERVATIONS
   

   And then run it with: ./HotelBookingCompiler my_commands.txt

5. Clean Up To remove the generated object files and the final executable, you can use the clean command from the Makefile.

   make clean

✨ Key Features

This project is the implementation of a compiler for a custom Domain-Specific Language (DSL) designed for managing hotel room reservations. The compiler is built in C using the standard compiler-construction tools, Flex and Bison.

The core features are:

1. Custom Domain-Specific Language (DSL): The project defines a simple, readable language for performing hotel management tasks. Based on your test files, the supported commands include:

   • LIST_ROOMS_AVAILABILITY <date>: Checks which rooms are free on a specific date.
   • BOOK_ROOM <room_number> <start_date> <end_date> "<guest_name>": Creates a new reservation for a room.
   • CANCEL_RESERVATION <reservation_id>: Cancels an existing reservation.
   • SHOW_RESERVATIONS: Lists all current reservations.

2. Classic Compiler Architecture: The compiler is built using a standard and robust toolchain:

   • Flex (Lexical Analysis): The scanner.l file defines the tokens of the language (keywords like BOOK_ROOM, numbers, strings, dates).
   • Bison (Syntactic Analysis): The parser.y file defines the grammar of the DSL, ensuring that sequences of tokens form valid commands.

3. Abstract Syntax Tree (AST): The compiler parses the source code and builds an Abstract Syntax Tree (as defined in include/ast.h). This tree is a structured, in-memory representation of the commands, which is a key component of a well-designed compiler.

4. Symbol Table Management: The project uses a Symbol Table (include/stable.h) to keep track of the state of the hotel, such as active reservations, associating reservation IDs with guest details and dates.

5. Direct Execution: The compiler interprets the AST and directly executes the commands, printing the results to the standard output (e.g., confirming a booking or listing available rooms).