> For the complete documentation index, see [llms.txt](https://faglobal.gitbook.io/fa-global-white-paper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://faglobal.gitbook.io/fa-global-white-paper/product-guides/contract.md). # Contract Contract Link : Code : /\*\* \*Submitted for verification at BscScan.com on 2024-08-16 \*/ // SPDX-License-Identifier: MIT // File @openzeppelin/contracts/utils/Context.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol) pragma solidity ^0.8.20; /\*\* * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. \*/ abstract contract Context { function \_msgSender() internal view virtual returns (address) { return msg.sender; } function \_msgData() internal view virtual returns (bytes calldata) { return msg.data; } function \_contextSuffixLength() internal view virtual returns (uint256) { return 0; } } // File @openzeppelin/contracts/access/Ownable.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol) pragma solidity ^0.8.20; /\*\* * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * The initial owner is set to the address provided by the deployer. This can * later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. \*/ abstract contract Ownable is Context { address private \_owner; /\*\* * @dev The caller account is not authorized to perform an operation. \*/ error OwnableUnauthorizedAccount(address account); /\*\* * @dev The owner is not a valid owner account. (eg. `address(0)`) \*/ error OwnableInvalidOwner(address owner); event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /\*\* * @dev Initializes the contract setting the address provided by the deployer as the initial owner. \*/ constructor(address initialOwner) { if (initialOwner == address(0)) { revert OwnableInvalidOwner(address(0)); } \_transferOwnership(initialOwner); } /\*\* * @dev Throws if called by any account other than the owner. \*/ modifier onlyOwner() { \_checkOwner(); \_; } /\*\* * @dev Returns the address of the current owner. \*/ function owner() public view virtual returns (address) { return \_owner; } /\*\* * @dev Throws if the sender is not the owner. \*/ function \_checkOwner() internal view virtual { if (owner() != \_msgSender()) { revert OwnableUnauthorizedAccount(\_msgSender()); } } /\*\* * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby disabling any functionality that is only available to the owner. \*/ function renounceOwnership() public virtual onlyOwner { \_transferOwnership(address(0)); } /\*\* * @dev Transfers ownership of the contract to a new account (`newOwner`). * Can only be called by the current owner. \*/ function transferOwnership(address newOwner) public virtual onlyOwner { if (newOwner == address(0)) { revert OwnableInvalidOwner(address(0)); } \_transferOwnership(newOwner); } /\*\* * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. \*/ function \_transferOwnership(address newOwner) internal virtual { address oldOwner = \_owner; \_owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } } // File @openzeppelin/contracts/interfaces/draft-IERC6093.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (interfaces/draft-IERC6093.sol) pragma solidity ^0.8.20; /\*\* * @dev Standard ERC20 Errors * Interface of the ] custom errors for ERC20 tokens. */ interface IERC20Errors { /*\* * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. * @param balance Current balance for the interacting account. * @param needed Minimum amount required to perform a transfer. \*/ error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed); /\*\* * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. \*/ error ERC20InvalidSender(address sender); /\*\* * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. \*/ error ERC20InvalidReceiver(address receiver); /\*\* * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers. * @param spender Address that may be allowed to operate on tokens without being their owner. * @param allowance Amount of tokens a `spender` is allowed to operate with. * @param needed Minimum amount required to perform a transfer. \*/ error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed); /\*\* * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. \*/ error ERC20InvalidApprover(address approver); /\*\* * @dev Indicates a failure with the `spender` to be approved. Used in approvals. * @param spender Address that may be allowed to operate on tokens without being their owner. \*/ error ERC20InvalidSpender(address spender); } /\*\* * @dev Standard ERC721 Errors * Interface of the ] custom errors for ERC721 tokens. */ interface IERC721Errors { /*\* * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20. * Used in balance queries. * @param owner Address of the current owner of a token. \*/ error ERC721InvalidOwner(address owner); /\*\* * @dev Indicates a `tokenId` whose `owner` is the zero address. * @param tokenId Identifier number of a token. \*/ error ERC721NonexistentToken(uint256 tokenId); /\*\* * @dev Indicates an error related to the ownership over a particular token. Used in transfers. * @param sender Address whose tokens are being transferred. * @param tokenId Identifier number of a token. * @param owner Address of the current owner of a token. \*/ error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner); /\*\* * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. \*/ error ERC721InvalidSender(address sender); /\*\* * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. \*/ error ERC721InvalidReceiver(address receiver); /\*\* * @dev Indicates a failure with the `operator`’s approval. Used in transfers. * @param operator Address that may be allowed to operate on tokens without being their owner. * @param tokenId Identifier number of a token. \*/ error ERC721InsufficientApproval(address operator, uint256 tokenId); /\*\* * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. \*/ error ERC721InvalidApprover(address approver); /\*\* * @dev Indicates a failure with the `operator` to be approved. Used in approvals. * @param operator Address that may be allowed to operate on tokens without being their owner. \*/ error ERC721InvalidOperator(address operator); } /\*\* * @dev Standard ERC1155 Errors * Interface of the ] custom errors for ERC1155 tokens. */ interface IERC1155Errors { /*\* * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. * @param balance Current balance for the interacting account. * @param needed Minimum amount required to perform a transfer. * @param tokenId Identifier number of a token. \*/ error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId); /\*\* * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. \*/ error ERC1155InvalidSender(address sender); /\*\* * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. \*/ error ERC1155InvalidReceiver(address receiver); /\*\* * @dev Indicates a failure with the `operator`’s approval. Used in transfers. * @param operator Address that may be allowed to operate on tokens without being their owner. * @param owner Address of the current owner of a token. \*/ error ERC1155MissingApprovalForAll(address operator, address owner); /\*\* * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. \*/ error ERC1155InvalidApprover(address approver); /\*\* * @dev Indicates a failure with the `operator` to be approved. Used in approvals. * @param operator Address that may be allowed to operate on tokens without being their owner. \*/ error ERC1155InvalidOperator(address operator); /\*\* * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation. * Used in batch transfers. * @param idsLength Length of the array of token identifiers * @param valuesLength Length of the array of token amounts \*/ error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength); } // File @openzeppelin/contracts/token/ERC20/IERC20.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol) pragma solidity ^0.8.20; /\*\* * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /*\* * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. \*/ event Transfer(address indexed from, address indexed to, uint256 value); /\*\* * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. \*/ event Approval(address indexed owner, address indexed spender, uint256 value); /\*\* * @dev Returns the value of tokens in existence. \*/ function totalSupply() external view returns (uint256); /\*\* * @dev Returns the value of tokens owned by `account`. \*/ function balanceOf(address account) external view returns (uint256); /\*\* * @dev Moves a `value` amount of tokens from the caller's account to `to`. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. \*/ function transfer(address to, uint256 value) external returns (bool); /\*\* * @dev Returns the remaining number of tokens that `spender` will be * allowed to spend on behalf of `owner` through {transferFrom}. This is * zero by default. * * This value changes when {approve} or {transferFrom} are called. \*/ function allowance(address owner, address spender) external view returns (uint256); /\*\* * @dev Sets a `value` amount of tokens as the allowance of `spender` over the * caller's tokens. * * Returns a boolean value indicating whether the operation succeeded. * * IMPORTANT: Beware that changing an allowance with this method brings the risk * that someone may use both the old and the new allowance by unfortunate * transaction ordering. One possible solution to mitigate this race * condition is to first reduce the spender's allowance to 0 and set the * desired value afterwards: * * * Emits an {Approval} event. \*/ function approve(address spender, uint256 value) external returns (bool); /\*\* * @dev Moves a `value` amount of tokens from `from` to `to` using the * allowance mechanism. `value` is then deducted from the caller's * allowance. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. \*/ function transferFrom(address from, address to, uint256 value) external returns (bool); } // File @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol) pragma solidity ^0.8.20; /\*\* * @dev Interface for the optional metadata functions from the ERC20 standard. */ interface IERC20Metadata is IERC20 { /*\* * @dev Returns the name of the token. \*/ function name() external view returns (string memory); /\*\* * @dev Returns the symbol of the token. \*/ function symbol() external view returns (string memory); /\*\* * @dev Returns the decimals places of the token. \*/ function decimals() external view returns (uint8); } // File @openzeppelin/contracts/token/ERC20/ERC20.sol\@v5.0.2 // Original license: SPDX\_License\_Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol) pragma solidity ^0.8.20; /\*\* * @dev Implementation of the {IERC20} interface. * * This implementation is agnostic to the way tokens are created. This means * that a supply mechanism has to be added in a derived contract using {\_mint}. * * TIP: For a detailed writeup see our guide * * to implement supply mechanisms]. * * The default value of {decimals} is 18. To change this, you should override * this function so it returns a different value. * * We have followed general OpenZeppelin Contracts guidelines: functions revert * instead returning `false` on failure. This behavior is nonetheless * conventional and does not conflict with the expectations of ERC20 * applications. * * Additionally, an {Approval} event is emitted on calls to {transferFrom}. * This allows applications to reconstruct the allowance for all accounts just * by listening to said events. Other implementations of the EIP may not emit * these events, as it isn't required by the specification. \*/ abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors { mapping(address account => uint256) private \_balances; mapping(address account => mapping(address spender => uint256)) private \_allowances; uint256 private \_totalSupply; string private \_name; string private \_symbol; /\*\* * @dev Sets the values for {name} and {symbol}. * * All two of these values are immutable: they can only be set once during * construction. \*/ constructor(string memory name\_, string memory symbol\_) { *name = name*; *symbol = symbol*; } /\*\* * @dev Returns the name of the token. \*/ function name() public view virtual returns (string memory) { return \_name; } /\*\* * @dev Returns the symbol of the token, usually a shorter version of the * name. \*/ function symbol() public view virtual returns (string memory) { return \_symbol; } /\*\* * @dev Returns the number of decimals used to get its user representation. * For example, if `decimals` equals `2`, a balance of `505` tokens should * be displayed to a user as `5.05` (`505 / 10 ** 2`). * * Tokens usually opt for a value of 18, imitating the relationship between * Ether and Wei. This is the default value returned by this function, unless * it's overridden. * * NOTE: This information is only used for *display* purposes: it in * no way affects any of the arithmetic of the contract, including * {IERC20-balanceOf} and {IERC20-transfer}. \*/ function decimals() public view virtual returns (uint8) { return 18; } /\*\* * @dev See {IERC20-totalSupply}. \*/ function totalSupply() public view virtual returns (uint256) { return \_totalSupply; } /\*\* * @dev See {IERC20-balanceOf}. \*/ function balanceOf(address account) public view virtual returns (uint256) { return \_balances\[account]; } /\*\* * @dev See {IERC20-transfer}. * * Requirements: * * * `to` cannot be the zero address. * * the caller must have a balance of at least `value`. \*/ function transfer(address to, uint256 value) public virtual returns (bool) { address owner = \_msgSender(); \_transfer(owner, to, value); return true; } /\*\* * @dev See {IERC20-allowance}. \*/ function allowance(address owner, address spender) public view virtual returns (uint256) { return \_allowances\[owner]\[spender]; } /\*\* * @dev See {IERC20-approve}. * * NOTE: If `value` is the maximum `uint256`, the allowance is not updated on * `transferFrom`. This is semantically equivalent to an infinite approval. * * Requirements: * * * `spender` cannot be the zero address. \*/ function approve(address spender, uint256 value) public virtual returns (bool) { address owner = \_msgSender(); \_approve(owner, spender, value); return true; } /\*\* * @dev See {IERC20-transferFrom}. * * Emits an {Approval} event indicating the updated allowance. This is not * required by the EIP. See the note at the beginning of {ERC20}. * * NOTE: Does not update the allowance if the current allowance * is the maximum `uint256`. * * Requirements: * * * `from` and `to` cannot be the zero address. * * `from` must have a balance of at least `value`. * * the caller must have allowance for `from`'s tokens of at least * `value`. \*/ function transferFrom(address from, address to, uint256 value) public virtual returns (bool) { address spender = \_msgSender(); \_spendAllowance(from, spender, value); \_transfer(from, to, value); return true; } /\*\* * @dev Moves a `value` amount of tokens from `from` to `to`. * * This internal function is equivalent to {transfer}, and can be used to * e.g. implement automatic token fees, slashing mechanisms, etc. * * Emits a {Transfer} event. * * NOTE: This function is not virtual, {\_update} should be overridden instead. \*/ function \_transfer(address from, address to, uint256 value) internal { if (from == address(0)) { revert ERC20InvalidSender(address(0)); } if (to == address(0)) { revert ERC20InvalidReceiver(address(0)); } \_update(from, to, value); } /\*\* * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from` * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding * this function. * * Emits a {Transfer} event. \*/ function \_update(address from, address to, uint256 value) internal virtual { if (from == address(0)) { // Overflow check required: The rest of the code assumes that totalSupply never overflows \_totalSupply += value; } else { uint256 fromBalance = \_balances\[from]; if (fromBalance < value) { revert ERC20InsufficientBalance(from, fromBalance, value); } unchecked { // Overflow not possible: value <= fromBalance <= totalSupply. \_balances\[from] = fromBalance - value; } } if (to == address(0)) { unchecked { // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply. \_totalSupply -= value; } } else { unchecked { // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256. \_balances\[to] += value; } } emit Transfer(from, to, value); } /\*\* * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0). * Relies on the `_update` mechanism * * Emits a {Transfer} event with `from` set to the zero address. * * NOTE: This function is not virtual, {\_update} should be overridden instead. \*/ function \_mint(address account, uint256 value) internal { if (account == address(0)) { revert ERC20InvalidReceiver(address(0)); } \_update(address(0), account, value); } /\*\* * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply. * Relies on the `_update` mechanism. * * Emits a {Transfer} event with `to` set to the zero address. * * NOTE: This function is not virtual, {\_update} should be overridden instead \*/ function \_burn(address account, uint256 value) internal { if (account == address(0)) { revert ERC20InvalidSender(address(0)); } \_update(account, address(0), value); } /\*\* * @dev Sets `value` as the allowance of `spender` over the `owner` s tokens. * * This internal function is equivalent to `approve`, and can be used to * e.g. set automatic allowances for certain subsystems, etc. * * Emits an {Approval} event. * * Requirements: * * * `owner` cannot be the zero address. * * `spender` cannot be the zero address. * * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument. \*/ function \_approve(address owner, address spender, uint256 value) internal { \_approve(owner, spender, value, true); } /\*\* * @dev Variant of {\_approve} with an optional flag to enable or disable the {Approval} event. * * By default (when calling {\_approve}) the flag is set to true. On the other hand, approval changes made by * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any * `Approval` event during `transferFrom` operations. * * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to * true using the following override: * ``` ``` * function \_approve(address owner, address spender, uint256 value, bool) internal virtual override { * ``` super._approve(owner, spender, value, true); ``` * } * ``` ``` * * Requirements are the same as {\_approve}. \*/ function \_approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual { if (owner == address(0)) { revert ERC20InvalidApprover(address(0)); } if (spender == address(0)) { revert ERC20InvalidSpender(address(0)); } \_allowances\[owner]\[spender] = value; if (emitEvent) { emit Approval(owner, spender, value); } } /\*\* * @dev Updates `owner` s allowance for `spender` based on spent `value`. * * Does not update the allowance value in case of infinite allowance. * Revert if not enough allowance is available. * * Does not emit an {Approval} event. \*/ function \_spendAllowance(address owner, address spender, uint256 value) internal virtual { uint256 currentAllowance = allowance(owner, spender); if (currentAllowance != type(uint256).max) { if (currentAllowance < value) { revert ERC20InsufficientAllowance(spender, currentAllowance, value); } unchecked { \_approve(owner, spender, currentAllowance - value, false); } } } } // File contracts/access/BEP20TokenOwner.sol // Original license: SPDX\_License\_Identifier: MIT pragma solidity ^0.8.20; /\*\* * @title BEP20TokenOwner * @dev Ownable contract with deployer set as initial owner. Adds the required `getOwner` method for BEP20. */ abstract contract BEP20TokenOwner is Ownable { /*\* * @dev Initializes the contract setting the deployer as the initial owner. \*/ constructor() Ownable(\_msgSender()) {} /\*\* * @dev Returns the contract owner. \*/ function getOwner() external view returns (address) { return owner(); } } // File contracts/service/ServicePayer.sol // Original license: SPDX\_License\_Identifier: MIT pragma solidity ^0.8.20; /\*\* * @title IPayable \*/ interface IPayable { function pay(string calldata serviceName, bytes calldata signature, address wallet) external payable; } /\*\* * @title ServicePayer * @dev Utility contract to pay the deployment fee. Used only during construction. \*/ abstract contract ServicePayer { constructor(address payable receiver, string memory serviceName, bytes memory signature, address wallet) payable { IPayable(receiver).pay{value: msg.value}(serviceName, signature, wallet); } } // File contracts/token/ERC20/extensions/ERC20Decimals.sol // Original license: SPDX\_License\_Identifier: MIT pragma solidity ^0.8.20; /\*\* * @title ERC20Decimals * @dev Extension of ERC20 that adds decimals storage slot. \*/ abstract contract ERC20Decimals is ERC20 { // indicates the decimals amount uint8 private immutable \_decimals; /\*\* * @dev Sets the value of the `_decimals`. * This value is immutable, it can only be set once during construction. \*/ constructor(uint8 decimals\_) { *decimals = decimals*; } /\*\* * @inheritdoc IERC20Metadata \*/ function decimals() public view virtual override returns (uint8) { return \_decimals; } } // File contracts/token/ERC20/extensions/ERC20Detailed.sol // Original license: SPDX\_License\_Identifier: MIT pragma solidity ^0.8.20; /\*\* * @title ERC20Detailed * @dev Extension of ERC20 and ERC20Decimals. \*/ abstract contract ERC20Detailed is ERC20Decimals { constructor( string memory name\_, string memory symbol\_, uint8 decimals\_ ) ERC20(name\_, symbol\_) ERC20Decimals(decimals\_) {} } // File contracts/token/BEP20/StandardBEP20.sol // Original license: SPDX\_License\_Identifier: MIT pragma solidity ^0.8.20; /\*\* * @title StandardBEP20 * @dev Implementation of the StandardBEP20. \*/ contract StandardBEP20 is ERC20Detailed, BEP20TokenOwner, ServicePayer { constructor( string memory name\_, string memory symbol\_, uint8 decimals\_, uint256 initialBalance\_, bytes memory signature\_, address payable feeReceiver\_ ) payable ERC20Detailed(name\_, symbol\_, decimals\_) ServicePayer(feeReceiver\_, "StandardBEP20", signature\_, *msgSender()) { require(initialBalance* > 0, "Initial supply cannot be zero"); ``` _mint(_msgSender(), initialBalance_); ``` } }