1、流程图
2、ERC20代码详解
1）、基本合约提供总发行量，余额，交易转账函数以及转账事件
2）、SafeMath加减乘除library 库
library SafeMath {
/**
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
assert(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Substracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
3）、ERC20合约提供允许转账金额查询，从A账户到B账户的交易，授权A-》B的转账以及授权事件
4）、实现ERC20Basic合约的function
5）、实现ERC20, BasicToken合约
3、锁仓解锁代码：
1）、创建创世块
2）、定义管理员，为了对代币进行管理，首先需要给合约添加一个管理者。
3）、锁仓解锁合约核心代码，由于注释完备，所以就不叙述。
/**
* @dev 锁仓解锁合约
*/
contract LibraTokenVault is Ownable {
using SafeMath for uint256;
/**
* @dev 创建三个账户地址，将解锁后的余额预分配到三个地址
* 每个地址根据不同的解锁时间，在调用合约后将对应的余额按照一定规则转移到相应的地址
*/
address public teamReserveWallet = 0x373c69fDedE072A3F5ab1843a0e5fE0102Cc6793;
address public firstReserveWallet = 0x99C83f62DBE1a488f9C9d370DA8e86EC55224eB4;
address public secondReserveWallet = 0x90DfF11810dA6227d348C86C59257C1C0033D307;
/** 三个账户地址对应的锁仓金额 */
uint256 public teamReserveAllocation = 2 * (10 ** 8) * (10 ** 18);
uint256 public firstReserveAllocation = 15 * (10 ** 7) * (10 ** 18);
uint256 public secondReserveAllocation = 15 * (10 ** 7) * (10 ** 18);
// 总锁仓的金额
uint256 public totalAllocation = 5 * (10 ** 8) * (10 ** 18);
/** 三个账户地址对应的锁仓时间 */
uint256 public teamTimeLock = 2 * 365 days;
/** 分多少次解锁到对应的地址 */
uint256 public teamVestingStages = 8;
uint256 public firstReserveTimeLock = 2 * 365 days;
uint256 public secondReserveTimeLock = 3 * 365 days;
/** Reserve allocations */
mapping(address => uint256) public allocations; // 每个地址对应锁仓金额的映射表
/** When timeLocks are over (UNIX Timestamp) */
mapping(address => uint256) public timeLocks; // 每个地址对应锁仓时间的映射表
/** How many tokens each reserve wallet has claimed */
mapping(address => uint256) public claimed; // 每个地址对应锁仓后已经解锁的金额的映射表
/** When this vault was locked (UNIX Timestamp)*/
uint256 public lockedAt = 0;
LibraToken public token;
/** Allocated reserve tokens */
event Allocated(address wallet, uint256 value);
/** Distributed reserved tokens */
event Distributed(address wallet, uint256 value);
/** Tokens have been locked */
event Locked(uint256 lockTime);
//Any of the three reserve wallets
modifier onlyReserveWallets { // 合约调用者的锁仓余额大于0才能查询锁仓余额
require(allocations[msg.sender] > 0);
_;
}
//Only Libra team reserve wallet
modifier onlyTeamReserve { // 合约调用者的地址为teamReserveWallet
require(msg.sender == teamReserveWallet);
require(allocations[msg.sender] > 0);
_;
}
//Only first and second token reserve wallets
modifier onlyTokenReserve { // 合约调用者的地址为firstReserveWallet或者secondReserveWallet
require(msg.sender == firstReserveWallet || msg.sender == secondReserveWallet);
require(allocations[msg.sender] > 0);
_;
}
//Has not been locked yet
modifier notLocked { // 未锁定
require(lockedAt == 0);
_;
}
modifier locked { // 锁定
require(lockedAt > 0);
_;
}
//Token allocations have not been set
modifier notAllocated { // 没有为每个地址分配对应的锁仓金额时
require(allocations[teamReserveWallet] == 0);
require(allocations[firstReserveWallet] == 0);
require(allocations[secondReserveWallet] == 0);
_;
}
function LibraTokenVault(ERC20 _token) public { // 构造LibraToken模式的合约
owner = msg.sender; // msg.sender 是指直接调用当前合约的调用方地址
token = LibraToken(_token);
}
/* 当合约调用者是ower时才可执行锁仓功能，锁仓为解锁对应的地址分配对应金额
* 调用分配事件
* 分配成功后，执行锁操作
*/
function allocate() public notLocked notAllocated onlyOwner {
//Makes sure Token Contract has the exact number of tokens
require(token.balanceOf(address(this)) == totalAllocation); // 合约调用方要求锁的金额与预定义分配的金额是否相等
allocations[teamReserveWallet] = teamReserveAllocation;
allocations[firstReserveWallet] = firstReserveAllocation;
allocations[secondReserveWallet] = secondReserveAllocation;
Allocated(teamReserveWallet, teamReserveAllocation);
Allocated(firstReserveWallet, firstReserveAllocation);
Allocated(secondReserveWallet, secondReserveAllocation);
lock();
}
/* internal：内部函数，并且只有owner才拥有才权限
* 从调用该合约的lock方法起，算出每一个地址对应的解锁时间
* 执行锁事件
*/
function lock() internal notLocked onlyOwner {
lockedAt = block.timestamp; // 区块当前时间
timeLocks[teamReserveWallet] = lockedAt.add(teamTimeLock);
timeLocks[firstReserveWallet] = lockedAt.add(firstReserveTimeLock);
timeLocks[secondReserveWallet] = lockedAt.add(secondReserveTimeLock);
Locked(lockedAt);
}
//In the case locking failed, then allow the owner to reclaim the tokens on the contract.
//Recover Tokens in case incorrect amount was sent to contract.
// 失败回滚
function recoverFailedLock() external notLocked notAllocated onlyOwner {
// Transfer all tokens on this contract back to the owner
require(token.transfer(owner, token.balanceOf(address(this))));
}
// Total number of tokens currently in the vault
// 查询当前合约所持有的金额
function getTotalBalance() public view returns (uint256 tokensCurrentlyInVault) {
return token.balanceOf(address(this));
}
// Number of tokens that are still locked
// 根据锁住的地址查询对应锁住的金额
function getLockedBalance() public view onlyReserveWallets returns (uint256 tokensLocked) {
return allocations[msg.sender].sub(claimed[msg.sender]); // 某一个地址对应的分配金额-该地址已经解锁的金额
}
//Claim tokens for first/second reserve wallets
/* 解锁函数，拥有firstReserveWallet或者secondReserveWallet地址的用户才具有此权限，并且此地址已经被锁住，当前时间大于该地址的解锁时间
* 从调用该合约的lock方法起，算出每一个地址对应的解锁时间
* 执行锁事件
*/
function claimTokenReserve() onlyTokenReserve locked public {
address reserveWallet = msg.sender;
// Can't claim before Lock ends
require(block.timestamp > timeLocks[reserveWallet]); // 当前时间大于第一个或者第二个解锁时间
// Must Only claim once
require(claimed[reserveWallet] == 0); // 已解锁发放出额度为0
uint256 amount = allocations[reserveWallet]; // 当前账号分配量
claimed[reserveWallet] = amount; // 一次性解锁发放
require(token.transfer(reserveWallet, amount)); // 解锁到对应的地址
Distributed(reserveWallet, amount);
}
//Claim tokens for Libra team reserve wallet
/* 解锁函数，拥有teamReserveWallet地址的用户才具有此权限，并且此地址已经被锁住，当前时间大于该地址的解锁时间
* 从调用该合约的lock方法起，算出每一个地址对应的解锁时间,每三个月发放一次
* 执行锁事件
*/
function claimTeamReserve() onlyTeamReserve locked public {
uint256 vestingStage = teamVestingStage();
//Amount of tokens the team should have at this vesting stage
uint256 totalUnlocked = vestingStage.mul(allocations[teamReserveWallet]).div(teamVestingStages); // 总的解锁量
require(totalUnlocked <= allocations[teamReserveWallet]);
//Previously claimed tokens must be less than what is unlocked
require(claimed[teamReserveWallet] < totalUnlocked); // 解锁已经发放量<总的解锁量
uint256 payment = totalUnlocked.sub(claimed[teamReserveWallet]); // 本次解锁发放量 = 总的解锁量 - 解锁已经发放量
claimed[teamReserveWallet] = totalUnlocked; // 解锁已经发放量 = 总的解锁量
require(token.transfer(teamReserveWallet, payment)); // 发放
Distributed(teamReserveWallet, payment);
}
//Current Vesting stage for Libra team
function teamVestingStage() public view onlyTeamReserve returns(uint256){
// Every 3 months
uint256 vestingMonths = teamTimeLock.div(teamVestingStages); // 解锁每个的时间=锁定时间/解锁次数
uint256 stage = (block.timestamp.sub(lockedAt)).div(vestingMonths); // 已经解锁的次数 =（当前时间-锁定时间)/每个解锁时间
//Ensures team vesting stage doesn't go past teamVestingStages
if(stage > teamVestingStages){ // 已经解锁的次数大于解锁次数
stage = teamVestingStages;
}
return stage;
}
}
4、全部代码
pragma solidity ^0.4.18;
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/179
*/
contract ERC20Basic {
function totalSupply() public view returns (uint256); // totalSupply - 总发行量
function balanceOf(address who) public view returns (uint256); // 余额
function transfer(address to, uint256 value) public returns (bool); // 交易
event Transfer(address indexed from, address indexed to, uint256 value); // 交易事件
}
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
assert(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Substracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender) public view returns (uint256); // 获取被授权令牌余额,获取 _owner 地址授权给 _spender 地址可以转移的令牌的余额
function transferFrom(address from, address to, uint256 value) public returns (bool); // A账户-》B账户的转账
function approve(address spender, uint256 value) public returns (bool); // 授权，允许 _spender 地址从你的账户中转移 _value 个令牌到任何地方
event Approval(address indexed owner, address indexed spender, uint256 value); // 授权事件
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances; // 余额
uint256 totalSupply_; // 发行总量
/**
* @dev total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return totalSupply_;
}
/**
* @dev transfer token for a specified address
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/
function transfer(address _to, uint256 _value) public returns (bool) {
require(_to != address(0)); // 无效地址
require(_value <= balances[msg.sender]); // 转账账户余额大于转账数目
// SafeMath.sub will throw if there is not enough balance.
balances[msg.sender] = balances[msg.sender].sub(_value); // 转账账户余额=账户余额-转账金额
balances[_to] = balances[_to].add(_value); // 接收账户的余额=原先账户余额+账金额
Transfer(msg.sender, _to, _value); // 转账
return true;
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner]; // 查询合约调用者的余额
}
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* @dev https://github.com/ethereum/EIPs/issues/20
* @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract StandardToken is ERC20, BasicToken {
mapping (address => mapping (address => uint256)) internal allowed;
/**
* @dev Transfer tokens from one address to another
* @param _from address The address which you want to send tokens from
* @param _to address The address which you want to transfer to
* @param _value uint256 the amount of tokens to be transferred
*/
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
require(_to != address(0)); // 到达B账户的地址不能为无效地址
require(_value <= balances[_from]); // 转账账户余额大于转账金额
require(_value <= allowed[_from][msg.sender]); // 允许_from地址转账给 _to地址
balances[_from] = balances[_from].sub(_value);
balances[_to] = balances[_to].add(_value);
allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value); // 允许转账的余额
Transfer(_from, _to, _value);
return true;
}
/**
* 设置帐户允许支付的最大金额
*
* 一般在智能合约的时候，避免支付过多，造成风险
*
* @param _spender 帐户地址
* @param _value 金额
*/
function approve(address _spender, uint256 _value) public returns (bool) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param _owner address The address which owns the funds.
* @param _spender address The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address _owner, address _spender) public view returns (uint256) {
return allowed[_owner][_spender];
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param _spender The address which will spend the funds.
* @param _addedValue The amount of tokens to increase the allowance by.
增加允许支付的最大额度
*/
function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param _spender The address which will spend the funds.
* @param _subtractedValue The amount of tokens to decrease the allowance by.
减少允许支付的最大额度
*/
function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
uint oldValue = allowed[msg.sender][_spender];
if (_subtractedValue > oldValue) {
allowed[msg.sender][_spender] = 0;
} else {
allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
}
Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
}
/**
* @title SimpleToken
* @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
* Note they can later distribute these tokens as they wish using `transfer` and other
* `StandardToken` functions. 初始化合约，并且把初始的所有代币都给这合约的创建者
*/
contract LibraToken is StandardToken {
string public constant name = "LibraToken"; // solium-disable-line uppercase
string public constant symbol = "LBA"; // solium-disable-line uppercase
uint8 public constant decimals = 18; // solium-disable-line uppercase
uint256 public constant INITIAL_SUPPLY = (10 ** 9) * (10 ** uint256(decimals));
/**
* @dev Constructor that gives msg.sender all of existing tokens.
*/
function LibraToken() public {
totalSupply_ = INITIAL_SUPPLY;
balances[msg.sender] = INITIAL_SUPPLY;
Transfer(0x0, msg.sender, INITIAL_SUPPLY);
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions". 为了对代币进行管理，首先需要给合约添加一个管理者
*/
contract Ownable {
address public owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() public {
owner = msg.sender;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to. 指派一个新的管理员
*/
function transferOwnership(address newOwner) public onlyOwner {
require(newOwner != address(0));
OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
}
/**
* @dev 锁仓解锁合约
*/
contract LibraTokenVault is Ownable {
using SafeMath for uint256;
/**
* @dev 创建三个账户地址，将解锁后的余额预分配到三个地址
*/
address public teamReserveWallet = 0x373c69fDedE072A3F5ab1843a0e5fE0102Cc6793;
address public firstReserveWallet = 0x99C83f62DBE1a488f9C9d370DA8e86EC55224eB4;
address public secondReserveWallet = 0x90DfF11810dA6227d348C86C59257C1C0033D307;
/** 三个账户地址对应的锁仓金额 */
uint256 public teamReserveAllocation = 2 * (10 ** 8) * (10 ** 18);
uint256 public firstReserveAllocation = 15 * (10 ** 7) * (10 ** 18);
uint256 public secondReserveAllocation = 15 * (10 ** 7) * (10 ** 18);
// 总锁仓的金额
uint256 public totalAllocation = 5 * (10 ** 8) * (10 ** 18);
/** 三个账户地址对应的锁仓时间 */
uint256 public teamTimeLock = 2 * 365 days;
uint256 public teamVestingStages = 8;
uint256 public firstReserveTimeLock = 2 * 365 days;
uint256 public secondReserveTimeLock = 3 * 365 days;
/** Reserve allocations */
mapping(address => uint256) public allocations; // 每个地址对应锁仓金额的映射表
/** When timeLocks are over (UNIX Timestamp) */
mapping(address => uint256) public timeLocks; // 每个地址对应锁仓时间的映射表
/** How many tokens each reserve wallet has claimed */
mapping(address => uint256) public claimed; // 每个地址对应锁仓后已经解锁的金额的映射表
/** When this vault was locked (UNIX Timestamp)*/
uint256 public lockedAt = 0;
LibraToken public token;
/** Allocated reserve tokens */
event Allocated(address wallet, uint256 value);
/** Distributed reserved tokens */
event Distributed(address wallet, uint256 value);
/** Tokens have been locked */
event Locked(uint256 lockTime);
//Any of the three reserve wallets
modifier onlyReserveWallets { // 合约调用者的锁仓余额大于0才能查询锁仓余额
require(allocations[msg.sender] > 0);
_;
}
//Only Libra team reserve wallet
modifier onlyTeamReserve { // 合约调用者的地址为teamReserveWallet
require(msg.sender == teamReserveWallet);
require(allocations[msg.sender] > 0);
_;
}
//Only first and second token reserve wallets
modifier onlyTokenReserve { // 合约调用者的地址为firstReserveWallet或者secondReserveWallet
require(msg.sender == firstReserveWallet || msg.sender == secondReserveWallet);
require(allocations[msg.sender] > 0);
_;
}
//Has not been locked yet
modifier notLocked { // 未锁定
require(lockedAt == 0);
_;
}
modifier locked { // 锁定
require(lockedAt > 0);
_;
}
//Token allocations have not been set
modifier notAllocated { // 没有为每个地址分配对应的锁仓金额时
require(allocations[teamReserveWallet] == 0);
require(allocations[firstReserveWallet] == 0);
require(allocations[secondReserveWallet] == 0);
_;
}
function LibraTokenVault(ERC20 _token) public { // 构造LibraToken模式的合约
owner = msg.sender; // msg.sender 是指直接调用当前合约的调用方地址
token = LibraToken(_token);
}
function allocate() public notLocked notAllocated onlyOwner {
//Makes sure Token Contract has the exact number of tokens
require(token.balanceOf(address(this)) == totalAllocation);
allocations[teamReserveWallet] = teamReserveAllocation;
allocations[firstReserveWallet] = firstReserveAllocation;
allocations[secondReserveWallet] = secondReserveAllocation;
Allocated(teamReserveWallet, teamReserveAllocation);
Allocated(firstReserveWallet, firstReserveAllocation);
Allocated(secondReserveWallet, secondReserveAllocation);
lock();
}
function lock() internal notLocked onlyOwner {
lockedAt = block.timestamp; // 区块当前时间
timeLocks[teamReserveWallet] = lockedAt.add(teamTimeLock);
timeLocks[firstReserveWallet] = lockedAt.add(firstReserveTimeLock);
timeLocks[secondReserveWallet] = lockedAt.add(secondReserveTimeLock);
Locked(lockedAt);
}
function recoverFailedLock() external notLocked notAllocated onlyOwner {
// Transfer all tokens on this contract back to the owner
require(token.transfer(owner, token.balanceOf(address(this))));
}
// Total number of tokens currently in the vault
// 查询当前合约所持有的金额
function getTotalBalance() public view returns (uint256 tokensCurrentlyInVault) {
return token.balanceOf(address(this));
}
// Number of tokens that are still locked
function getLockedBalance() public view onlyReserveWallets returns (uint256 tokensLocked) {
return allocations[msg.sender].sub(claimed[msg.sender]);
}
//Claim tokens for first/second reserve wallets
function claimTokenReserve() onlyTokenReserve locked public {
address reserveWallet = msg.sender;
// Can't claim before Lock ends
require(block.timestamp > timeLocks[reserveWallet]);
// Must Only claim once
require(claimed[reserveWallet] == 0);
uint256 amount = allocations[reserveWallet];
claimed[reserveWallet] = amount; // 一次性解锁发放
require(token.transfer(reserveWallet, amount));
Distributed(reserveWallet, amount);
}
//Claim tokens for Libra team reserve wallet
function claimTeamReserve() onlyTeamReserve locked public {
uint256 vestingStage = teamVestingStage();
//Amount of tokens the team should have at this vesting stage
uint256 totalUnlocked = vestingStage.mul(allocations[teamReserveWallet]).div(teamVestingStages); // 总的解锁量
require(totalUnlocked <= allocations[teamReserveWallet]);
//Previously claimed tokens must be less than what is unlocked
require(claimed[teamReserveWallet] < totalUnlocked);
uint256 payment = totalUnlocked.sub(claimed[teamReserveWallet]);
claimed[teamReserveWallet] = totalUnlocked;
require(token.transfer(teamReserveWallet, payment));
Distributed(teamReserveWallet, payment);
}
//Current Vesting stage for Libra team
function teamVestingStage() public view onlyTeamReserve returns(uint256){
// Every 3 months
uint256 vestingMonths = teamTimeLock.div(teamVestingStages);
uint256 stage = (block.timestamp.sub(lockedAt)).div(vestingMonths);
//Ensures team vesting stage doesn't go past teamVestingStages
return stage;
}
}
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