📚 ISBN Validator and Generator

🔍 A Simple and Efficient C Utility for Validating and Generating ISBN-10 and ISBN-13 Codes 🔍

Table of Contents

• Introduction
• Features
• System Requirements
• Installation
• Getting Started
• Usage
• Contributing
• Security
• Code of Conduct
• Support
• License
• Acknowledgements

Introduction

ISBN Validator and Generator is an open-source command-line utility written in C, designed to validate and generate International Standard Book Number (ISBN) codes in both ISBN-10 and ISBN-13 formats. It provides a simple and efficient way to check the validity of ISBN codes or create valid or intentionally invalid codes for testing purposes. This tool is ideal for developers, librarians, publishers, or anyone working with book identifiers.

The utility adheres to the official ISBN standards, handling checksum calculations and input validation robustly. As an open-source project, it encourages contributions to enhance functionality, improve performance, or add new features.

Note: This project is actively maintained. Some edge cases (e.g., malformed input handling) may have limitations. Your feedback is valuable!

Features

• ISBN Validation:
  • Validates ISBN-10 (10-digit) and ISBN-13 (13-digit) codes.
  • Supports input with or without hyphens (e.g., 0-306-40615-2 or 0306406152).
  • Checks for correct format and calculates checksums to confirm validity.
  • Handles ISBN-10’s special case where the checksum may be 'X'.
• ISBN Generation:
  • Generates valid ISBN-10 and ISBN-13 codes with correct checksums.
  • Generates invalid (fake) ISBN-10 and ISBN-13 codes with intentionally incorrect checksums for testing.
  • Randomly creates digits for the ISBN body, ensuring realistic output.
• User Interface:
  • Interactive command-line menu for selecting validation or generation tasks.
  • Clear prompts and error messages for user input.
• Robust Input Handling:
  • Removes hyphens from input for consistent validation.
  • Validates input length and character types (digits, 'X' for ISBN-10).
• Portable Code:
  • Written in standard C, compatible with most platforms (Windows, Linux, macOS).
  • Minimal dependencies (standard C libraries only).

System Requirements

To build and run ISBN Validator and Generator, ensure you have:

• Operating System: Windows, Linux, macOS, or any system with a C compiler.
• C Compiler: GCC, Clang, MSVC, or any standard-compliant C compiler.
• Disk Space: Minimal (~1 MB for source code and compiled binary).
• Dependencies: Standard C libraries (stdio.h, stdlib.h, time.h, string.h, ctype.h).
• Build Tools: make (optional, for automating compilation).

Installation

Follow these steps to set up and build the project locally:

1. Clone the Repository:

   git clone https://github.com/VoxDroid/ISBN-Validator-Generator.git

2. Navigate to the Project Directory:

   cd ISBN-Validator-Generator

3. Compile the Source Code:

   • Using GCC or Clang:

     gcc main.c -o isbn_validator

   • Using MSVC (Windows):

     cl main.c /o isbn_validator.exe

   • Alternatively, create a Makefile for convenience:

     CC = gcc
     CFLAGS = -Wall -O2
     TARGET = isbn_validator
     
     all: $(TARGET)
     
     $(TARGET): main.c
         $(CC) $(CFLAGS) main.c -o $(TARGET)
     
     clean:
         rm -f $(TARGET)

     Then run:

     make

4. Verify Compilation:

   • Ensure the executable (isbn_validator or isbn_validator.exe) is created.
   • Run the program to confirm it starts:

     ./isbn_validator

Note: If compilation fails, ensure your compiler is installed and configured correctly. Check for errors related to missing standard libraries.

Getting Started

To use ISBN Validator and Generator:

1. Run the Program:

   • On Linux/macOS:

     ./isbn_validator

   • On Windows:

     isbn_validator.exe

2. Interact with the Menu:

   • The program displays a menu with four options:
     • 1. Validate ISBN: Check if an ISBN-10 or ISBN-13 is valid.
     • 2. Generate Fake ISBN: Create an invalid ISBN-10 or ISBN-13.
     • 3. Generate Real ISBN: Create a valid ISBN-10 or ISBN-13.
     • 4. Exit: Quit the program.
   • Enter a number (1–4) to select an option.

3. Test Functionality:

   • Validation: Enter a known ISBN (e.g., 0-306-40615-2 for ISBN-10 or 978-0-306-40615-7 for ISBN-13) to verify it’s recognized as valid.
   • Generation: Generate a real ISBN-10 and validate it manually or with the program to confirm correctness.
   • Fake Generation: Generate a fake ISBN and attempt to validate it to ensure it’s flagged as invalid.

Usage

Validating an ISBN

• Select option 1 from the menu.
• Enter an ISBN-10 (10 digits) or ISBN-13 (13 digits), with or without hyphens.
• The program:
  • Removes hyphens for processing.
  • Checks the length (10 or 13 digits).
  • Validates the format (digits only, except 'X' for ISBN-10’s checksum).
  • Computes the checksum and confirms validity.
• Output: “The ISBN-10/13 code is valid” or “The ISBN-10/13 code is invalid.”

Example:

Enter the ISBN to validate: 0-306-40615-2
The ISBN-10 code is valid.

Generating a Fake ISBN

• Select option 2 and choose the ISBN type (1 for ISBN-10, 2 for ISBN-13).
• The program:
  • Generates random digits for the ISBN body (9 for ISBN-10, 12 for ISBN-13).
  • Calculates a correct checksum, then selects an incorrect one to ensure invalidity.
  • For ISBN-10, the checksum may be 'X' (if 10).
• Output: A fake ISBN that will fail validation.

Example:

Choose ISBN type: 1
Generated Fake ISBN-10: 1234567890

Generating a Real ISBN

• Select option 3 and choose the ISBN type (1 for ISBN-10, 2 for ISBN-13).
• The program:
  • Generates random digits for the ISBN body.
  • Computes the correct checksum per ISBN standards.
  • For ISBN-10, the checksum may be 'X' (if 10).
• Output: A valid ISBN that passes validation.

Example:

Choose ISBN type: 2
Generated Real ISBN-13: 9781234567890

Exiting

• Select option 4 to close the program.

Contributing

We welcome contributions to ISBN Validator and Generator! To get involved:

• Review the Contributing Guidelines for details on submitting issues, feature requests, or pull requests.
• Fork the repository, make changes, and submit a pull request.
• Adhere to the Code of Conduct to ensure a respectful community.

Example contributions:

• Add support for ISBN prefix validation (e.g., valid EAN prefixes for ISBN-13).
• Improve input handling for edge cases (e.g., whitespace, special characters).
• Optimize checksum calculations for performance.
• Add unit tests for validation and generation functions.

Security

Security is a priority for ISBN Validator and Generator. If you discover a vulnerability:

• Report it privately as outlined in the Security Policy.
• Avoid public disclosure until the issue is resolved.

Code of Conduct

All contributors and users are expected to follow the Code of Conduct to maintain a welcoming and inclusive environment.

Support

Need help with ISBN Validator and Generator? Visit the Support page for resources, including:

• Filing bug reports or feature requests.
• Community discussions and contact information.
• FAQs for common issues (e.g., compilation errors, invalid input handling).

License

ISBN Validator and Generator is licensed under the MIT License. See the LICENSE file for details.

Acknowledgements

• VoxDroid: For creating and maintaining the project.
• Contributors: Thanks to all who report issues, suggest features, or contribute code.
• ISBN Standards: Based on the official specifications from the International ISBN Agency.

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Developed by VoxDroid

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