pragma solidity ^0.4.24;
import "../token/ERC20/ERC20.sol";
import "../math/SafeMath.sol";
import "../token/ERC20/SafeERC20.sol";
/**
* @title Crowdsale
* @dev Crowdsale is a base contract for managing a token crowdsale,
* allowing investors to purchase tokens with ether. This contract implements
* such functionality in its most fundamental form and can be extended to provide additional
* functionality and/or custom behavior.
* The external interface represents the basic interface for purchasing tokens, and conform
* the base architecture for crowdsales. They are *not* intended to be modified / overridden.
* The internal interface conforms the extensible and modifiable surface of crowdsales. Override
* the methods to add functionality. Consider using 'super' where appropriate to concatenate
* behavior.
*/
contract Crowdsale {
using SafeMath for uint256;
using SafeERC20 for ERC20;
// The token being sold
ERC20 public token; // 用于发型的TOKEN
// Address where funds are collected
address public wallet; // 钱包地址，用于存储众筹所得的以太币
// How many token units a buyer gets per wei.
// The rate is the conversion between wei and the smallest and indivisible token unit.
// So, if you are using a rate of 1 with a DetailedERC20 token with 3 decimals called TOK
// 1 wei will give you 1 unit, or 0.001 TOK.
uint256 public rate; // 和以太币的汇率兑换(以wei位基本单位)
// Amount of wei raised
uint256 public weiRaised;
/**
* Event for token purchase logging
* @param purchaser who paid for the tokens
* @param beneficiary who got the tokens
* @param value weis paid for purchase
* @param amount amount of tokens purchased
*/
// 购买token的记录
event TokenPurchase(
address indexed purchaser, // 买家
address indexed beneficiary, // 受益人
uint256 value, // 费用
uint256 amount // 购买的token数量
);
/**
* @param _rate Number of token units a buyer gets per wei
* @param _wallet Address where collected funds will be forwarded to
* @param _token Address of the token being sold
*/
constructor(uint256 _rate, address _wallet, ERC20 _token) public {
require(_rate > 0);
require(_wallet != address(0));
require(_token != address(0));
rate = _rate;
wallet = _wallet;
token = _token;
}
// -----------------------------------------
// Crowdsale external interface
// -----------------------------------------
/**
* @dev fallback function ***DO NOT OVERRIDE***
*/
function () external payable {
buyTokens(msg.sender);
}
/**
* @dev low level token purchase ***DO NOT OVERRIDE***
* @param _beneficiary Address performing the token purchase
*/
// 买token
function buyTokens(address _beneficiary) public payable {
uint256 weiAmount = msg.value;
_preValidatePurchase(_beneficiary, weiAmount);
// calculate token amount to be created
uint256 tokens = _getTokenAmount(weiAmount);
// update state
weiRaised = weiRaised.add(weiAmount);
_processPurchase(_beneficiary, tokens);
emit TokenPurchase(
msg.sender,
_beneficiary,
weiAmount,
tokens
);
_updatePurchasingState(_beneficiary, weiAmount);
_forwardFunds();
_postValidatePurchase(_beneficiary, weiAmount);
}
// -----------------------------------------
// Internal interface (extensible)
// -----------------------------------------
/**
* @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met. Use `super` in contracts that inherit from Crowdsale to extend their validations.
* Example from CappedCrowdsale.sol's _preValidatePurchase method:
* super._preValidatePurchase(_beneficiary, _weiAmount);
* require(weiRaised.add(_weiAmount) <= cap);
* @param _beneficiary Address performing the token purchase
* @param _weiAmount Value in wei involved in the purchase
*/
// 前置检查
function _preValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
{
require(_beneficiary != address(0));
require(_weiAmount != 0);
}
/**
* @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid conditions are not met.
* @param _beneficiary Address performing the token purchase
* @param _weiAmount Value in wei involved in the purchase
*/
// 购买执行之后的验证，在条件不满足时，回滚状态
function _postValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
{
// optional override
}
/**
* @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends its tokens.
* @param _beneficiary Address performing the token purchase
* @param _tokenAmount Number of tokens to be emitted
*/
// 交互token
function _deliverTokens(
address _beneficiary,
uint256 _tokenAmount
)
internal
{
token.safeTransfer(_beneficiary, _tokenAmount);
}
/**
* @dev Executed when a purchase has been validated and is ready to be executed. Not necessarily emits/sends tokens.
* @param _beneficiary Address receiving the tokens
* @param _tokenAmount Number of tokens to be purchased
*/
function _processPurchase(
address _beneficiary,
uint256 _tokenAmount
)
internal
{
_deliverTokens(_beneficiary, _tokenAmount);
}
/**
* @dev Override for extensions that require an internal state to check for validity (current user contributions, etc.)
* @param _beneficiary Address receiving the tokens
* @param _weiAmount Value in wei involved in the purchase
*/
function _updatePurchasingState(
address _beneficiary,
uint256 _weiAmount
)
internal
{
// optional override
}
/**
* @dev Override to extend the way in which ether is converted to tokens.
* @param _weiAmount Value in wei to be converted into tokens
* @return Number of tokens that can be purchased with the specified _weiAmount
*/
// 获取到token数量
function _getTokenAmount(uint256 _weiAmount)
internal view returns (uint256)
{
return _weiAmount.mul(rate);
}
/**
* @dev Determines how ETH is stored/forwarded on purchases.
*/
// 确定购买是转发以太币
function _forwardFunds() internal {
wallet.transfer(msg.value);
}
}
pragma solidity ^0.4.24;
import "../../math/SafeMath.sol";
import "../Crowdsale.sol";
/**
* @title CappedCrowdsale
* @dev Crowdsale with a limit for total contributions.
*/
// 众筹上限合约
contract CappedCrowdsale is Crowdsale {
using SafeMath for uint256;
uint256 public cap; // 众筹的上限
/**
* @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
* @param _cap Max amount of wei to be contributed
*/
constructor(uint256 _cap) public {
require(_cap > 0);
cap = _cap;
}
/**
* @dev Checks whether the cap has been reached.
* @return Whether the cap was reached
*/
// 检查众筹金额是否已经达到上限
function capReached() public view returns (bool) {
return weiRaised >= cap;
}
/**
* @dev Extend parent behavior requiring purchase to respect the funding cap.
* @param _beneficiary Token purchaser
* @param _weiAmount Amount of wei contributed
*/
function _preValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
{
super._preValidatePurchase(_beneficiary, _weiAmount);
require(weiRaised.add(_weiAmount) <= cap);
}
}
- IndividuallyCappedCrowdsale.sol:个人的众筹上限
pragma solidity ^0.4.24;
import "../../math/SafeMath.sol";
import "../Crowdsale.sol";
import "../../ownership/Ownable.sol";
/**
* @title IndividuallyCappedCrowdsale
* @dev Crowdsale with per-user caps.
*/
// 每一个用的购买上限
contract IndividuallyCappedCrowdsale is Crowdsale, Ownable {
using SafeMath for uint256;
mapping(address => uint256) public contributions;
mapping(address => uint256) public caps;
/**
* @dev Sets a specific user's maximum contribution.
* @param _beneficiary Address to be capped
* @param _cap Wei limit for individual contribution
*/
// 设置指定地址的上限
function setUserCap(address _beneficiary, uint256 _cap) external onlyOwner {
caps[_beneficiary] = _cap;
}
/**
* @dev Sets a group of users' maximum contribution.
* @param _beneficiaries List of addresses to be capped
* @param _cap Wei limit for individual contribution
*/
// 为指定的地址集合设置相同的上限
function setGroupCap(
address[] _beneficiaries,
uint256 _cap
)
external
onlyOwner
{
for (uint256 i = 0; i < _beneficiaries.length; i++) {
caps[_beneficiaries[i]] = _cap;
}
}
/**
* @dev Returns the cap of a specific user.
* @param _beneficiary Address whose cap is to be checked
* @return Current cap for individual user
*/
// 返回指定地址的购买上限
function getUserCap(address _beneficiary) public view returns (uint256) {
return caps[_beneficiary];
}
/**
* @dev Returns the amount contributed so far by a sepecific user.
* @param _beneficiary Address of contributor
* @return User contribution so far
*/
// 返回当前地址的购买量
function getUserContribution(address _beneficiary)
public view returns (uint256)
{
return contributions[_beneficiary];
}
/**
* @dev Extend parent behavior requiring purchase to respect the user's funding cap.
* @param _beneficiary Token purchaser
* @param _weiAmount Amount of wei contributed
*/
function _preValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
{
super._preValidatePurchase(_beneficiary, _weiAmount);
require(contributions[_beneficiary].add(_weiAmount) <= caps[_beneficiary]);
}
/**
* @dev Extend parent behavior to update user contributions
* @param _beneficiary Token purchaser
* @param _weiAmount Amount of wei contributed
*/
// 更新当前地址的众筹量
function _updatePurchasingState(
address _beneficiary,
uint256 _weiAmount
)
internal
{
super._updatePurchasingState(_beneficiary, _weiAmount);
contributions[_beneficiary] = contributions[_beneficiary].add(_weiAmount);
}
}
pragma solidity ^0.4.24;
import "../../math/SafeMath.sol";
import "../Crowdsale.sol";
/**
* @title TimedCrowdsale
* @dev Crowdsale accepting contributions only within a time frame.
*/
// 众筹时间范围
contract TimedCrowdsale is Crowdsale {
using SafeMath for uint256;
uint256 public openingTime; // 启动时间
uint256 public closingTime; // 结束时间
/**
* @dev Reverts if not in crowdsale time range.
*/
modifier onlyWhileOpen {
// solium-disable-next-line security/no-block-members
require(block.timestamp >= openingTime && block.timestamp <= closingTime);
_;
}
/**
* @dev Constructor, takes crowdsale opening and closing times.
* @param _openingTime Crowdsale opening time
* @param _closingTime Crowdsale closing time
*/
// 设置时间范围
constructor(uint256 _openingTime, uint256 _closingTime) public {
// solium-disable-next-line security/no-block-members
require(_openingTime >= block.timestamp);
require(_closingTime >= _openingTime);
openingTime = _openingTime;
closingTime = _closingTime;
}
/**
* @dev Checks whether the period in which the crowdsale is open has already elapsed.
* @return Whether crowdsale period has elapsed
*/
// 检验众筹是否已经关闭
function hasClosed() public view returns (bool) {
// solium-disable-next-line security/no-block-members
return block.timestamp > closingTime;
}
/**
* @dev Extend parent behavior requiring to be within contributing period
* @param _beneficiary Token purchaser
* @param _weiAmount Amount of wei contributed
*/
function _preValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
onlyWhileOpen
{
super._preValidatePurchase(_beneficiary, _weiAmount);
}
}
- WhitelistedCrowdsale.sol：白名单
pragma solidity ^0.4.24;
import "../Crowdsale.sol";
import "../../access/Whitelist.sol";
/**
* @title WhitelistedCrowdsale
* @dev Crowdsale in which only whitelisted users can contribute.
*/
// 可以参与众筹的白名单地址列表
contract WhitelistedCrowdsale is Whitelist, Crowdsale {
/**
* @dev Extend parent behavior requiring beneficiary to be in whitelist.
* @param _beneficiary Token beneficiary
* @param _weiAmount Amount of wei contributed
*/
function _preValidatePurchase(
address _beneficiary,
uint256 _weiAmount
)
internal
onlyIfWhitelisted(_beneficiary)
{
super._preValidatePurchase(_beneficiary, _weiAmount);
}
}
- IncreasingPriceCrowdsale.sol:token价格变动
pragma solidity ^0.4.24;
import "../validation/TimedCrowdsale.sol";
import "../../math/SafeMath.sol";
/**
* @title IncreasingPriceCrowdsale
* @dev Extension of Crowdsale contract that increases the price of tokens linearly in time.
* Note that what should be provided to the constructor is the initial and final _rates_, that is,
* the amount of tokens per wei contributed. Thus, the initial rate must be greater than the final rate.
*/
// 扩展的TOKEN合约，增加TOKEN价格
contract IncreasingPriceCrowdsale is TimedCrowdsale {
using SafeMath for uint256;
uint256 public initialRate;
uint256 public finalRate;
/**
* @dev Constructor, takes initial and final rates of tokens received per wei contributed.
* @param _initialRate Number of tokens a buyer gets per wei at the start of the crowdsale
* @param _finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
*/
constructor(uint256 _initialRate, uint256 _finalRate) public {
require(_initialRate >= _finalRate);
require(_finalRate > 0);
initialRate = _initialRate;
finalRate = _finalRate;
}
/**
* @dev Returns the rate of tokens per wei at the present time.
* Note that, as price _increases_ with time, the rate _decreases_.
* @return The number of tokens a buyer gets per wei at a given time
*/
// 获取当前兑换率
function getCurrentRate() public view returns (uint256) {
// solium-disable-next-line security/no-block-members
uint256 elapsedTime = block.timestamp.sub(openingTime);
uint256 timeRange = closingTime.sub(openingTime);
uint256 rateRange = initialRate.sub(finalRate);
return initialRate.sub(elapsedTime.mul(rateRange).div(timeRange));
}
/**
* @dev Overrides parent method taking into account variable rate.
* @param _weiAmount The value in wei to be converted into tokens
* @return The number of tokens _weiAmount wei will buy at present time
*/
// 获取当前的token数量
function _getTokenAmount(uint256 _weiAmount)
internal view returns (uint256)
{
uint256 currentRate = getCurrentRate();
return currentRate.mul(_weiAmount);
}
}
- RefundableCrowdsale.sol：退款
pragma solidity ^0.4.24;
import "../../math/SafeMath.sol";
import "./FinalizableCrowdsale.sol";
import "../../payment/RefundEscrow.sol";
/**
* @title RefundableCrowdsale
* @dev Extension of Crowdsale contract that adds a funding goal, and
* the possibility of users getting a refund if goal is not met.
*/
// 扩展合约，增加资金目标，或者在未达到目标是支持用户退块
contract RefundableCrowdsale is FinalizableCrowdsale {
using SafeMath for uint256;
// minimum amount of funds to be raised in weis
uint256 public goal;
// refund escrow used to hold funds while crowdsale is running
RefundEscrow private escrow;
/**
* @dev Constructor, creates RefundEscrow.
* @param _goal Funding goal
*/
constructor(uint256 _goal) public {
require(_goal > 0);
escrow = new RefundEscrow(wallet);
goal = _goal;
}
/**
* @dev Investors can claim refunds here if crowdsale is unsuccessful
*/
function claimRefund() public {
require(isFinalized);
require(!goalReached());
escrow.withdraw(msg.sender);
}
/**
* @dev Checks whether funding goal was reached.
* @return Whether funding goal was reached
*/
function goalReached() public view returns (bool) {
return weiRaised >= goal;
}
/**
* @dev escrow finalization task, called when owner calls finalize()
*/
function finalization() internal {
if (goalReached()) {
escrow.close();
escrow.beneficiaryWithdraw();
} else {
escrow.enableRefunds();
}
super.finalization();
}
/**
* @dev Overrides Crowdsale fund forwarding, sending funds to escrow.
*/
function _forwardFunds() internal {
escrow.deposit.value(msg.value)(msg.sender);
}
}
- PostDeliveryCrowdsale.sol：锁仓
pragma solidity ^0.4.24;
import "../validation/TimedCrowdsale.sol";
import "../../token/ERC20/ERC20.sol";
import "../../math/SafeMath.sol";
/**
* @title PostDeliveryCrowdsale
* @dev Crowdsale that locks tokens from withdrawal until it ends.
*/
// 锁定TOKEN(锁仓)
contract PostDeliveryCrowdsale is TimedCrowdsale {
using SafeMath for uint256;
mapping(address => uint256) public balances;
/**
* @dev Withdraw tokens only after crowdsale ends.
*/
function withdrawTokens() public {
require(hasClosed());
uint256 amount = balances[msg.sender];
require(amount > 0);
balances[msg.sender] = 0;
_deliverTokens(msg.sender, amount);
}
/**
* @dev Overrides parent by storing balances instead of issuing tokens right away.
* @param _beneficiary Token purchaser
* @param _tokenAmount Amount of tokens purchased
*/
function _processPurchase(
address _beneficiary,
uint256 _tokenAmount
)
internal
{
balances[_beneficiary] = balances[_beneficiary].add(_tokenAmount);
}
}
- FinalizableCrowdsale.sol:众筹完成之后的操作
pragma solidity ^0.4.24;
import "../../math/SafeMath.sol";
import "../../ownership/Ownable.sol";
import "../validation/TimedCrowdsale.sol";
/**
* @title FinalizableCrowdsale
* @dev Extension of Crowdsale where an owner can do extra work
* after finishing.
*/
// 在完成众筹之后所进行的额外操作
contract FinalizableCrowdsale is TimedCrowdsale, Ownable {
using SafeMath for uint256;
bool public isFinalized = false;
event Finalized();
/**
* @dev Must be called after crowdsale ends, to do some extra finalization
* work. Calls the contract's finalization function.
*/
function finalize() public onlyOwner {
require(!isFinalized);
require(hasClosed());
finalization();
emit Finalized();
isFinalized = true;
}
/**
* @dev Can be overridden to add finalization logic. The overriding function
* should call super.finalization() to ensure the chain of finalization is
* executed entirely.
*/
function finalization() internal {
}
}