🛠 Solidity Smart Contract Libraries

This repository contains a collection of versatile Solidity contracts and libraries designed to enhance smart contract development. The modules cover data structures, proxy patterns, access control, and security utilities like reentrancy locks.

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📚 Contents

🏗 Data Structures

1. Generalized Linked List Structure
2. BitMaps & MultiBitsMaps

🔄 Proxy Implementations

3. Self-Implemented Upgrade Proxy (ERC1967)
4. EIP-2535 Diamond Standard Implementation

🔒 Security & Utility Tools

5. Grant Privileges Smart Contract
6. Reentrancy Lock Libraries

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🏗 1. Generalized Linked List Structure

A flexible linked list implementation supporting various data types, optimized for performance and gas efficiency.

📄 Code Location

contracts/structs/LinkedList.sol

✨ Features

• Multi-Type Support: Stores bytes32, uint256, and address types.
• CRUD Operations: Add, remove, retrieve, and update elements with ease.
• Queue Implementation: Supports efficient LIFO (Last In, First Out) and FIFO (First In, First Out) queues.
• Gas Optimized: All operations are constant time O(1), including {clear} (excluding {values}).

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🏗 2. BitMaps & MultiBitsMaps

Efficient bitmap implementations to optimize storage and gas costs.

📄 Code Location

• contracts/utils/BitMaps.sol
• contracts/utils/MultiBitsMaps.sol

✨ Features

BitMaps

• Boolean value storage: Each bit represents true or false.
• Compact representation: Uses uint256 mapping for gas efficiency.
• Bitwise operations: Supports setting, clearing, and checking bits.

MultiBitsMaps

• Compact integer storage: Packs small values into a single uint256.
• Supported structures:
  • FourBitsMap: Stores values from {0, ..., 15} (4-bit values).
  • ByteMap: Stores values from {0, ..., 255} (8-bit values).
• Optimized storage: Reduces SSTORE operations for lower gas costs.

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🔄 3. Self-Implemented Transparent Upgradeable Proxy

A Transparent Upgradeable Proxy based on EIP-1967, ensuring smooth logic upgrades.

📄 Code Location

• contracts/proxy/ERC1967/ERC1967Utils.sol
• contracts/proxy/ERC1967/ProxyAdmin.sol
• contracts/proxy/ERC1967/TransparentUpgradeableProxy.sol

✨ Features

• EIP-1967 Compliant: Uses standard storage slots for proxy management.
• Admin-Controlled Upgrades: Allows only authorized addresses to upgrade the contract.
• Transparent Proxy Pattern: Prevents accidental admin calls by users.
• Fallback and Receive Functions: Supports forwarding of calls and Ether handling.

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🔄 4. EIP-2535 Diamond Standard Implementation

A modular and scalable smart contract system that enables dynamic function management.

📄 Code Location

• contracts/proxy/EIP2535/*.sol

✨ Features

• Modular Upgradability: Functions can be added, replaced, or removed.
• Storage Efficiency: Uses structured storage for managing multiple facets.
• Optimized Gas Usage: Calls only relevant functions, reducing execution costs.

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🔒 5. Grant Privileges Smart Contract

Implements time-based access control, allowing admins to grant temporary permissions.

📄 Code Location

• contracts/utils/GrantPrivileges.sol

✨ Features

• Admin-Controlled Access: Only the admin can manage privileged users.
• Time-Limited Roles: Users receive temporary access based on an expiration timestamp.
• Dynamic Management:
  • addOwner(address, uint): Grants access to a user for a limited time.
  • getRemainingTime(): Checks remaining access time.
  • changeAdmin(address): Transfers admin rights.

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🔒 6. Reentrancy Lock Libraries

Provides robust protection against reentrancy attacks using storage-based and transient storage-based locks (EIP-1153).

📄 Code Locations

• Transient Storage-Based Locks (EIP-1153)

  • contracts/utils/AbstractNonReentrantLockTransient.sol
  • contracts/utils/NonReentrantLockTransient.sol

• Standard Storage-Based Locks

  • contracts/utils/AbstractNonReentrantLock.sol
  • contracts/utils/NonReentrantLock.sol

✨ Features

• Default & Custom Locks: Supports simple and fine-grained locks.
• Gas Optimization: Transient storage locks reset automatically, reducing gas costs.
• EIP-1153 Compatibility: Uses transient storage if available, otherwise falls back to storage-based locks.

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🚀 Contributing

We welcome contributions! Feel free to submit pull requests or open issues for improvements and bug fixes.

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📜 License

This project is licensed under the MIT License.