/*!
* cpuminer.js - inefficient cpu miner for bcoin (because we can)
* Copyright (c) 2014-2015, Fedor Indutny (MIT License)
* Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
* https://github.com/bcoin-org/bcoin
*/
'use strict';
const assert = require('bsert');
const EventEmitter = require('events');
const {Lock} = require('bmutex');
const util = require('../utils/util');
const mine = require('./mine');
/**
* CPU miner.
* @alias module:mining.CPUMiner
*/
class CPUMiner extends EventEmitter {
/**
* Create a CPU miner.
* @constructor
* @param {Miner} miner
*/
constructor(miner) {
super();
this.opened = false;
this.miner = miner;
this.network = this.miner.network;
this.logger = this.miner.logger.context('cpuminer');
this.workers = this.miner.workers;
this.chain = this.miner.chain;
this.locker = new Lock();
this.running = false;
this.stopping = false;
this.job = null;
this.stopJob = null;
this.init();
}
/**
* Initialize the miner.
* @private
*/
init() {
this.chain.on('tip', (tip) => {
if (!this.job)
return;
if (this.job.attempt.prevBlock.equals(tip.prevBlock))
this.job.destroy();
});
}
/**
* Open the miner.
* @returns {Promise}
*/
async open() {
assert(!this.opened, 'CPUMiner is already open.');
this.opened = true;
}
/**
* Close the miner.
* @returns {Promise}
*/
async close() {
assert(this.opened, 'CPUMiner is not open.');
this.opened = false;
return this.stop();
}
/**
* Start mining.
* @method
*/
start() {
assert(!this.running, 'Miner is already running.');
this._start().catch(() => {});
}
/**
* Start mining.
* @method
* @private
* @returns {Promise}
*/
async _start() {
assert(!this.running, 'Miner is already running.');
this.running = true;
this.stopping = false;
for (;;) {
this.job = null;
try {
this.job = await this.createJob();
} catch (e) {
if (this.stopping)
break;
this.emit('error', e);
break;
}
if (this.stopping)
break;
let block;
try {
block = await this.mineAsync(this.job);
} catch (e) {
if (this.stopping)
break;
this.emit('error', e);
break;
}
if (this.stopping)
break;
if (!block)
continue;
let entry;
try {
entry = await this.chain.add(block);
} catch (e) {
if (this.stopping)
break;
if (e.type === 'VerifyError') {
this.logger.warning('Mined an invalid block!');
this.logger.error(e);
continue;
}
this.emit('error', e);
break;
}
if (!entry) {
this.logger.warning('Mined a bad-prevblk (race condition?)');
continue;
}
if (this.stopping)
break;
// Log the block hex as a failsafe (in case we can't send it).
this.logger.info('Found block: %d (%h).', entry.height, entry.hash);
this.emit('block', block, entry);
}
const job = this.stopJob;
if (job) {
this.stopJob = null;
job.resolve();
}
}
/**
* Stop mining.
* @method
* @returns {Promise}
*/
async stop() {
const unlock = await this.locker.lock();
try {
return await this._stop();
} finally {
unlock();
}
}
/**
* Stop mining (without a lock).
* @method
* @returns {Promise}
*/
async _stop() {
if (!this.running)
return;
assert(this.running, 'Miner is not running.');
assert(!this.stopping, 'Miner is already stopping.');
this.stopping = true;
if (this.job) {
this.job.destroy();
this.job = null;
}
await this.wait();
this.running = false;
this.stopping = false;
this.job = null;
}
/**
* Wait for `done` event.
* @private
* @returns {Promise}
*/
wait() {
return new Promise((resolve, reject) => {
assert(!this.stopJob);
this.stopJob = { resolve, reject };
});
}
/**
* Create a mining job.
* @method
* @param {ChainEntry?} tip
* @param {Address?} address
* @returns {Promise} - Returns {@link Job}.
*/
async createJob(tip, address) {
const attempt = await this.miner.createBlock(tip, address);
return new CPUJob(this, attempt);
}
/**
* Mine a single block.
* @method
* @param {ChainEntry?} tip
* @param {Address?} address
* @returns {Promise} - Returns [{@link Block}].
*/
async mineBlock(tip, address) {
const job = await this.createJob(tip, address);
return await this.mineAsync(job);
}
/**
* Notify the miner that a new
* tx has entered the mempool.
*/
notifyEntry() {
if (!this.running)
return;
if (!this.job)
return;
if (util.now() - this.job.start > 10) {
this.job.destroy();
this.job = null;
}
}
/**
* Hash until the nonce overflows.
* @param {CPUJob} job
* @returns {Number} nonce
*/
findNonce(job) {
const data = job.getHeader();
const target = job.attempt.target;
const interval = CPUMiner.INTERVAL;
let min = 0;
let max = interval;
let nonce;
while (max <= 0xffffffff) {
nonce = mine(data, target, min, max);
if (nonce !== -1)
break;
this.sendStatus(job, max);
min += interval;
max += interval;
}
return nonce;
}
/**
* Hash until the nonce overflows.
* @method
* @param {CPUJob} job
* @returns {Promise} Returns Number.
*/
async findNonceAsync(job) {
if (!this.workers)
return this.findNonce(job);
const data = job.getHeader();
const target = job.attempt.target;
const interval = CPUMiner.INTERVAL;
let min = 0;
let max = interval;
let nonce;
while (max <= 0xffffffff) {
nonce = await this.workers.mine(data, target, min, max);
if (nonce !== -1)
break;
if (job.destroyed)
return nonce;
this.sendStatus(job, max);
min += interval;
max += interval;
}
return nonce;
}
/**
* Mine synchronously until the block is found.
* @param {CPUJob} job
* @returns {Block}
*/
mine(job) {
job.start = util.now();
let nonce;
for (;;) {
nonce = this.findNonce(job);
if (nonce !== -1)
break;
job.updateNonce();
this.sendStatus(job, 0);
}
return job.commit(nonce);
}
/**
* Mine asynchronously until the block is found.
* @method
* @param {CPUJob} job
* @returns {Promise} - Returns {@link Block}.
*/
async mineAsync(job) {
let nonce;
job.start = util.now();
for (;;) {
nonce = await this.findNonceAsync(job);
if (nonce !== -1)
break;
if (job.destroyed)
return null;
job.updateNonce();
this.sendStatus(job, 0);
}
return job.commit(nonce);
}
/**
* Send a progress report (emits `status`).
* @param {CPUJob} job
* @param {Number} nonce
*/
sendStatus(job, nonce) {
const attempt = job.attempt;
const tip = attempt.prevBlock;
const hashes = job.getHashes(nonce);
const hashrate = job.getRate(nonce);
this.logger.info(
'Status: hashrate=%dkhs hashes=%d target=%d height=%d tip=%h',
Math.floor(hashrate / 1000),
hashes,
attempt.bits,
attempt.height,
tip);
this.emit('status', job, hashes, hashrate);
}
}
/**
* Nonce range interval.
* @const {Number}
* @default
*/
CPUMiner.INTERVAL = 0xffffffff / 1500 | 0;
/**
* Mining Job
* @ignore
*/
class CPUJob {
/**
* Create a mining job.
* @constructor
* @param {CPUMiner} miner
* @param {BlockTemplate} attempt
*/
constructor(miner, attempt) {
this.miner = miner;
this.attempt = attempt;
this.destroyed = false;
this.committed = false;
this.start = util.now();
this.nonce1 = 0;
this.nonce2 = 0;
this.refresh();
}
/**
* Get the raw block header.
* @param {Number} nonce
* @returns {Buffer}
*/
getHeader() {
const attempt = this.attempt;
const n1 = this.nonce1;
const n2 = this.nonce2;
const time = attempt.time;
const root = attempt.getRoot(n1, n2);
const data = attempt.getHeader(root, time, 0);
return data;
}
/**
* Commit job and return a block.
* @param {Number} nonce
* @returns {Block}
*/
commit(nonce) {
const attempt = this.attempt;
const n1 = this.nonce1;
const n2 = this.nonce2;
const time = attempt.time;
assert(!this.committed, 'Job already committed.');
this.committed = true;
const proof = attempt.getProof(n1, n2, time, nonce);
return attempt.commit(proof);
}
/**
* Mine block synchronously.
* @returns {Block}
*/
mine() {
return this.miner.mine(this);
}
/**
* Mine block asynchronously.
* @returns {Promise}
*/
mineAsync() {
return this.miner.mineAsync(this);
}
/**
* Refresh the block template.
*/
refresh() {
return this.attempt.refresh();
}
/**
* Increment the extraNonce.
*/
updateNonce() {
if (++this.nonce2 === 0x100000000) {
this.nonce2 = 0;
this.nonce1++;
}
}
/**
* Destroy the job.
*/
destroy() {
assert(!this.destroyed, 'Job already destroyed.');
this.destroyed = true;
}
/**
* Calculate number of hashes computed.
* @param {Number} nonce
* @returns {Number}
*/
getHashes(nonce) {
const extra = this.nonce1 * 0x100000000 + this.nonce2;
return extra * 0xffffffff + nonce;
}
/**
* Calculate hashrate.
* @param {Number} nonce
* @returns {Number}
*/
getRate(nonce) {
const hashes = this.getHashes(nonce);
const seconds = util.now() - this.start;
return Math.floor(hashes / Math.max(1, seconds));
}
/**
* Add a transaction to the block.
* @param {TX} tx
* @param {CoinView} view
*/
addTX(tx, view) {
return this.attempt.addTX(tx, view);
}
/**
* Add a transaction to the block
* (less verification than addTX).
* @param {TX} tx
* @param {CoinView?} view
*/
pushTX(tx, view) {
return this.attempt.pushTX(tx, view);
}
}
/*
* Expose
*/
module.exports = CPUMiner;