Contract Name:
SonikCoinToken
Contract Source Code:
File 1 of 1 : SonikCoinToken
// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;
/**
* @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 amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` 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 amount) 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 `amount` 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:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` 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 amount
) external returns (bool);
}
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
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);
}
/**
* @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;
}
}
/**
* @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.
*
* By default, the owner account will be the one that deploys the contract. 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;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @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 {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @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 {
require(
newOwner != address(0),
"Ownable: new owner is the zero address"
);
_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);
}
}
contract SonikCoinToken is Context, IERC20Metadata, Ownable {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
uint8 private constant _decimals = 18;
uint256 public constant hardCap = 299_792_458_000 * (10 ** _decimals);
/**
* @dev Contract constructor.
* @param name_ The name of the token.
* @param symbol_ The symbol of the token.
* @param _to The initial address to mint the total supply to.
*/
constructor(string memory name_, string memory symbol_, address _to) {
_name = name_;
_symbol = symbol_;
_mint(_to, hardCap);
}
/**
* @dev Returns the name of the token.
* @return The name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token.
* @return The symbol of the token.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used for token display.
* @return The number of decimals.
*/
function decimals() public view virtual override returns (uint8) {
return _decimals;
}
/**
* @dev Returns the total supply of the token.
* @return The total supply.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev Returns the balance of the specified account.
* @param account The address to check the balance for.
* @return The balance of the account.
*/
function balanceOf(
address account
) public view virtual override returns (uint256) {
return _balances[account];
}
/**
* @dev Transfers tokens from the caller to a specified recipient.
* @param recipient The address to transfer tokens to.
* @param amount The amount of tokens to transfer.
* @return A boolean value indicating whether the transfer was successful.
*/
function transfer(
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev Returns the amount of tokens that the spender is allowed to spend on behalf of the owner.
* @param from The address that approves the spending.
* @param to The address that is allowed to spend.
* @return The remaining allowance for the spender.
*/
function allowance(
address from,
address to
) public view virtual override returns (uint256) {
return _allowances[from][to];
}
/**
* @dev Approves the specified address to spend the specified amount of tokens on behalf of the caller.
* @param to The address to approve the spending for.
* @param amount The amount of tokens to approve.
* @return A boolean value indicating whether the approval was successful.
*/
function approve(
address to,
uint256 amount
) public virtual override returns (bool) {
_approve(_msgSender(), to, amount);
return true;
}
/**
* @dev Transfers tokens from one address to another.
* @param sender The address to transfer tokens from.
* @param recipient The address to transfer tokens to.
* @param amount The amount of tokens to transfer.
* @return A boolean value indicating whether the transfer was successful.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
uint256 currentAllowance = _allowances[sender][_msgSender()];
require(
currentAllowance >= amount,
"ERC20: transfer amount exceeds allowance"
);
unchecked {
_approve(sender, _msgSender(), currentAllowance - amount);
}
return true;
}
/**
* @dev Increases the allowance of the specified address to spend tokens on behalf of the caller.
* @param to The address to increase the allowance for.
* @param addedValue The amount of tokens to increase the allowance by.
* @return A boolean value indicating whether the increase was successful.
*/
function increaseAllowance(
address to,
uint256 addedValue
) public virtual returns (bool) {
_approve(_msgSender(), to, _allowances[_msgSender()][to] + addedValue);
return true;
}
/**
* @dev Decreases the allowance granted by the owner of the tokens to `to` account.
* @param to The account allowed to spend the tokens.
* @param subtractedValue The amount of tokens to decrease the allowance by.
* @return A boolean value indicating whether the operation succeeded.
*/
function decreaseAllowance(
address to,
uint256 subtractedValue
) public virtual returns (bool) {
uint256 currentAllowance = _allowances[_msgSender()][to];
require(
currentAllowance >= subtractedValue,
"ERC20: decreased allowance below zero"
);
unchecked {
_approve(_msgSender(), to, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Transfers `amount` tokens from `sender` to `recipient`.
* @param sender The account to transfer tokens from.
* @param recipient The account to transfer tokens to.
* @param amount The amount of tokens to transfer.
*/
function _transfer(
address sender,
address recipient,
uint256 amount
) internal virtual {
require(amount > 0, "ERC20: transfer amount zero");
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
uint256 senderBalance = _balances[sender];
require(
senderBalance >= amount,
"ERC20: transfer amount exceeds balance"
);
unchecked {
_balances[sender] = senderBalance - amount;
}
_balances[recipient] += amount;
emit Transfer(sender, recipient, amount);
}
/**
* @dev Creates `amount` tokens and assigns them to `account`.
* @param account The account to assign the newly created tokens to.
* @param amount The amount of tokens to create.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply += amount;
_balances[account] += amount;
emit Transfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the total supply.
* @param account The account to burn tokens from.
* @param amount The amount of tokens to burn.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
}
_totalSupply -= amount;
emit Transfer(account, address(0), amount);
}
/**
* @dev Destroys `amount` tokens from the caller's account, reducing the total supply.
* @param amount The amount of tokens to burn.
*/
function burn(uint256 amount) external {
_burn(_msgSender(), amount);
}
/**
* @dev Sets `amount` as the allowance of `to` over the caller's tokens.
* @param from The account granting the allowance.
* @param to The account allowed to spend the tokens.
* @param amount The amount of tokens to allow.
*/
function _approve(
address from,
address to,
uint256 amount
) internal virtual {
require(from != address(0), "ERC20: approve from the zero address");
require(to != address(0), "ERC20: approve to the zero address");
_allowances[from][to] = amount;
emit Approval(from, to, amount);
}
}