lbrycrd/src/miner.cpp
2015-12-13 18:08:39 +01:00

520 lines
19 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2015 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "miner.h"
#include "amount.h"
#include "chain.h"
#include "chainparams.h"
#include "coins.h"
#include "consensus/consensus.h"
#include "consensus/merkle.h"
#include "consensus/validation.h"
#include "hash.h"
#include "main.h"
#include "net.h"
#include "policy/policy.h"
#include "pow.h"
#include "primitives/transaction.h"
#include "script/standard.h"
#include "timedata.h"
#include "txmempool.h"
#include "util.h"
#include "utilmoneystr.h"
#include "validationinterface.h"
#include <boost/thread.hpp>
#include <boost/tuple/tuple.hpp>
#include <queue>
using namespace std;
//////////////////////////////////////////////////////////////////////////////
//
// BitcoinMiner
//
//
// Unconfirmed transactions in the memory pool often depend on other
// transactions in the memory pool. When we select transactions from the
// pool, we select by highest priority or fee rate, so we might consider
// transactions that depend on transactions that aren't yet in the block.
uint64_t nLastBlockTx = 0;
uint64_t nLastBlockSize = 0;
class ScoreCompare
{
public:
ScoreCompare() {}
bool operator()(const CTxMemPool::txiter a, const CTxMemPool::txiter b)
{
return CompareTxMemPoolEntryByScore()(*b,*a); // Convert to less than
}
};
int64_t UpdateTime(CBlockHeader* pblock, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev)
{
int64_t nOldTime = pblock->nTime;
int64_t nNewTime = std::max(pindexPrev->GetMedianTimePast()+1, GetAdjustedTime());
if (nOldTime < nNewTime)
pblock->nTime = nNewTime;
// Updating time can change work required on testnet:
if (consensusParams.fPowAllowMinDifficultyBlocks)
pblock->nBits = GetNextWorkRequired(pindexPrev, pblock, consensusParams);
return nNewTime - nOldTime;
}
CBlockTemplate* CreateNewBlock(const CChainParams& chainparams, const CScript& scriptPubKeyIn)
{
// Create new block
auto_ptr<CBlockTemplate> pblocktemplate(new CBlockTemplate());
if(!pblocktemplate.get())
return NULL;
CBlock *pblock = &pblocktemplate->block; // pointer for convenience
// -regtest only: allow overriding block.nVersion with
// -blockversion=N to test forking scenarios
if (chainparams.MineBlocksOnDemand())
pblock->nVersion = GetArg("-blockversion", pblock->nVersion);
// Create coinbase tx
CMutableTransaction txNew;
txNew.vin.resize(1);
txNew.vin[0].prevout.SetNull();
txNew.vout.resize(1);
txNew.vout[0].scriptPubKey = scriptPubKeyIn;
// Add dummy coinbase tx as first transaction
pblock->vtx.push_back(CTransaction());
pblocktemplate->vTxFees.push_back(-1); // updated at end
pblocktemplate->vTxSigOps.push_back(-1); // updated at end
// Largest block you're willing to create:
unsigned int nBlockMaxSize = GetArg("-blockmaxsize", DEFAULT_BLOCK_MAX_SIZE);
// Limit to between 1K and MAX_BLOCK_SIZE-1K for sanity:
nBlockMaxSize = std::max((unsigned int)1000, std::min((unsigned int)(MAX_BLOCK_SIZE-1000), nBlockMaxSize));
// How much of the block should be dedicated to high-priority transactions,
// included regardless of the fees they pay
unsigned int nBlockPrioritySize = GetArg("-blockprioritysize", DEFAULT_BLOCK_PRIORITY_SIZE);
nBlockPrioritySize = std::min(nBlockMaxSize, nBlockPrioritySize);
// Minimum block size you want to create; block will be filled with free transactions
// until there are no more or the block reaches this size:
unsigned int nBlockMinSize = GetArg("-blockminsize", DEFAULT_BLOCK_MIN_SIZE);
nBlockMinSize = std::min(nBlockMaxSize, nBlockMinSize);
// Collect memory pool transactions into the block
CTxMemPool::setEntries inBlock;
CTxMemPool::setEntries waitSet;
// This vector will be sorted into a priority queue:
vector<TxCoinAgePriority> vecPriority;
TxCoinAgePriorityCompare pricomparer;
std::map<CTxMemPool::txiter, double, CTxMemPool::CompareIteratorByHash> waitPriMap;
typedef std::map<CTxMemPool::txiter, double, CTxMemPool::CompareIteratorByHash>::iterator waitPriIter;
double actualPriority = -1;
std::priority_queue<CTxMemPool::txiter, std::vector<CTxMemPool::txiter>, ScoreCompare> clearedTxs;
bool fPrintPriority = GetBoolArg("-printpriority", DEFAULT_PRINTPRIORITY);
uint64_t nBlockSize = 1000;
uint64_t nBlockTx = 0;
unsigned int nBlockSigOps = 100;
int lastFewTxs = 0;
CAmount nFees = 0;
{
LOCK2(cs_main, mempool.cs);
CBlockIndex* pindexPrev = chainActive.Tip();
const int nHeight = pindexPrev->nHeight + 1;
pblock->nTime = GetAdjustedTime();
const int64_t nMedianTimePast = pindexPrev->GetMedianTimePast();
int64_t nLockTimeCutoff = (STANDARD_LOCKTIME_VERIFY_FLAGS & LOCKTIME_MEDIAN_TIME_PAST)
? nMedianTimePast
: pblock->GetBlockTime();
bool fPriorityBlock = nBlockPrioritySize > 0;
if (fPriorityBlock) {
vecPriority.reserve(mempool.mapTx.size());
for (CTxMemPool::indexed_transaction_set::iterator mi = mempool.mapTx.begin();
mi != mempool.mapTx.end(); ++mi)
{
double dPriority = mi->GetPriority(nHeight);
CAmount dummy;
mempool.ApplyDeltas(mi->GetTx().GetHash(), dPriority, dummy);
vecPriority.push_back(TxCoinAgePriority(dPriority, mi));
}
std::make_heap(vecPriority.begin(), vecPriority.end(), pricomparer);
}
CTxMemPool::indexed_transaction_set::nth_index<3>::type::iterator mi = mempool.mapTx.get<3>().begin();
CTxMemPool::txiter iter;
while (mi != mempool.mapTx.get<3>().end() || !clearedTxs.empty())
{
bool priorityTx = false;
if (fPriorityBlock && !vecPriority.empty()) { // add a tx from priority queue to fill the blockprioritysize
priorityTx = true;
iter = vecPriority.front().second;
actualPriority = vecPriority.front().first;
std::pop_heap(vecPriority.begin(), vecPriority.end(), pricomparer);
vecPriority.pop_back();
}
else if (clearedTxs.empty()) { // add tx with next highest score
iter = mempool.mapTx.project<0>(mi);
mi++;
}
else { // try to add a previously postponed child tx
iter = clearedTxs.top();
clearedTxs.pop();
}
if (inBlock.count(iter))
continue; // could have been added to the priorityBlock
const CTransaction& tx = iter->GetTx();
bool fOrphan = false;
BOOST_FOREACH(CTxMemPool::txiter parent, mempool.GetMemPoolParents(iter))
{
if (!inBlock.count(parent)) {
fOrphan = true;
break;
}
}
if (fOrphan) {
if (priorityTx)
waitPriMap.insert(std::make_pair(iter,actualPriority));
else
waitSet.insert(iter);
continue;
}
unsigned int nTxSize = iter->GetTxSize();
if (fPriorityBlock &&
(nBlockSize + nTxSize >= nBlockPrioritySize || !AllowFree(actualPriority))) {
fPriorityBlock = false;
waitPriMap.clear();
}
if (!priorityTx &&
(iter->GetModifiedFee() < ::minRelayTxFee.GetFee(nTxSize) && nBlockSize >= nBlockMinSize)) {
break;
}
if (nBlockSize + nTxSize >= nBlockMaxSize) {
if (nBlockSize > nBlockMaxSize - 100 || lastFewTxs > 50) {
break;
}
// Once we're within 1000 bytes of a full block, only look at 50 more txs
// to try to fill the remaining space.
if (nBlockSize > nBlockMaxSize - 1000) {
lastFewTxs++;
}
continue;
}
if (!IsFinalTx(tx, nHeight, nLockTimeCutoff))
continue;
unsigned int nTxSigOps = iter->GetSigOpCount();
if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS) {
if (nBlockSigOps > MAX_BLOCK_SIGOPS - 2) {
break;
}
continue;
}
CAmount nTxFees = iter->GetFee();
// Added
pblock->vtx.push_back(tx);
pblocktemplate->vTxFees.push_back(nTxFees);
pblocktemplate->vTxSigOps.push_back(nTxSigOps);
nBlockSize += nTxSize;
++nBlockTx;
nBlockSigOps += nTxSigOps;
nFees += nTxFees;
if (fPrintPriority)
{
double dPriority = iter->GetPriority(nHeight);
CAmount dummy;
mempool.ApplyDeltas(tx.GetHash(), dPriority, dummy);
LogPrintf("priority %.1f fee %s txid %s\n",
dPriority , CFeeRate(iter->GetModifiedFee(), nTxSize).ToString(), tx.GetHash().ToString());
}
inBlock.insert(iter);
// Add transactions that depend on this one to the priority queue
BOOST_FOREACH(CTxMemPool::txiter child, mempool.GetMemPoolChildren(iter))
{
if (fPriorityBlock) {
waitPriIter wpiter = waitPriMap.find(child);
if (wpiter != waitPriMap.end()) {
vecPriority.push_back(TxCoinAgePriority(wpiter->second,child));
std::push_heap(vecPriority.begin(), vecPriority.end(), pricomparer);
waitPriMap.erase(wpiter);
}
}
else {
if (waitSet.count(child)) {
clearedTxs.push(child);
waitSet.erase(child);
}
}
}
}
nLastBlockTx = nBlockTx;
nLastBlockSize = nBlockSize;
LogPrintf("CreateNewBlock(): total size %u txs: %u fees: %ld sigops %d\n", nBlockSize, nBlockTx, nFees, nBlockSigOps);
// Compute final coinbase transaction.
txNew.vout[0].nValue = nFees + GetBlockSubsidy(nHeight, chainparams.GetConsensus());
txNew.vin[0].scriptSig = CScript() << nHeight << OP_0;
pblock->vtx[0] = txNew;
pblocktemplate->vTxFees[0] = -nFees;
// Fill in header
pblock->hashPrevBlock = pindexPrev->GetBlockHash();
UpdateTime(pblock, chainparams.GetConsensus(), pindexPrev);
pblock->nBits = GetNextWorkRequired(pindexPrev, pblock, chainparams.GetConsensus());
pblock->nNonce = 0;
pblocktemplate->vTxSigOps[0] = GetLegacySigOpCount(pblock->vtx[0]);
CValidationState state;
if (!TestBlockValidity(state, chainparams, *pblock, pindexPrev, false, false)) {
throw std::runtime_error(strprintf("%s: TestBlockValidity failed: %s", __func__, FormatStateMessage(state)));
}
}
return pblocktemplate.release();
}
void IncrementExtraNonce(CBlock* pblock, const CBlockIndex* pindexPrev, unsigned int& nExtraNonce)
{
// Update nExtraNonce
static uint256 hashPrevBlock;
if (hashPrevBlock != pblock->hashPrevBlock)
{
nExtraNonce = 0;
hashPrevBlock = pblock->hashPrevBlock;
}
++nExtraNonce;
unsigned int nHeight = pindexPrev->nHeight+1; // Height first in coinbase required for block.version=2
CMutableTransaction txCoinbase(pblock->vtx[0]);
txCoinbase.vin[0].scriptSig = (CScript() << nHeight << CScriptNum(nExtraNonce)) + COINBASE_FLAGS;
assert(txCoinbase.vin[0].scriptSig.size() <= 100);
pblock->vtx[0] = txCoinbase;
pblock->hashMerkleRoot = BlockMerkleRoot(*pblock);
}
//////////////////////////////////////////////////////////////////////////////
//
// Internal miner
//
//
// ScanHash scans nonces looking for a hash with at least some zero bits.
// The nonce is usually preserved between calls, but periodically or if the
// nonce is 0xffff0000 or above, the block is rebuilt and nNonce starts over at
// zero.
//
bool static ScanHash(const CBlockHeader *pblock, uint32_t& nNonce, uint256 *phash)
{
// Write the first 76 bytes of the block header to a double-SHA256 state.
CHash256 hasher;
CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
ss << *pblock;
assert(ss.size() == 80);
hasher.Write((unsigned char*)&ss[0], 76);
while (true) {
nNonce++;
// Write the last 4 bytes of the block header (the nonce) to a copy of
// the double-SHA256 state, and compute the result.
CHash256(hasher).Write((unsigned char*)&nNonce, 4).Finalize((unsigned char*)phash);
// Return the nonce if the hash has at least some zero bits,
// caller will check if it has enough to reach the target
if (((uint16_t*)phash)[15] == 0)
return true;
// If nothing found after trying for a while, return -1
if ((nNonce & 0xfff) == 0)
return false;
}
}
static bool ProcessBlockFound(const CBlock* pblock, const CChainParams& chainparams)
{
LogPrintf("%s\n", pblock->ToString());
LogPrintf("generated %s\n", FormatMoney(pblock->vtx[0].vout[0].nValue));
// Found a solution
{
LOCK(cs_main);
if (pblock->hashPrevBlock != chainActive.Tip()->GetBlockHash())
return error("BitcoinMiner: generated block is stale");
}
// Inform about the new block
GetMainSignals().BlockFound(pblock->GetHash());
// Process this block the same as if we had received it from another node
CValidationState state;
if (!ProcessNewBlock(state, chainparams, NULL, pblock, true, NULL))
return error("BitcoinMiner: ProcessNewBlock, block not accepted");
return true;
}
void static BitcoinMiner(const CChainParams& chainparams)
{
LogPrintf("BitcoinMiner started\n");
SetThreadPriority(THREAD_PRIORITY_LOWEST);
RenameThread("bitcoin-miner");
unsigned int nExtraNonce = 0;
boost::shared_ptr<CReserveScript> coinbaseScript;
GetMainSignals().ScriptForMining(coinbaseScript);
try {
// Throw an error if no script was provided. This can happen
// due to some internal error but also if the keypool is empty.
// In the latter case, already the pointer is NULL.
if (!coinbaseScript || coinbaseScript->reserveScript.empty())
throw std::runtime_error("No coinbase script available (mining requires a wallet)");
while (true) {
if (chainparams.MiningRequiresPeers()) {
// Busy-wait for the network to come online so we don't waste time mining
// on an obsolete chain. In regtest mode we expect to fly solo.
do {
bool fvNodesEmpty;
{
LOCK(cs_vNodes);
fvNodesEmpty = vNodes.empty();
}
if (!fvNodesEmpty && !IsInitialBlockDownload())
break;
MilliSleep(1000);
} while (true);
}
//
// Create new block
//
unsigned int nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
CBlockIndex* pindexPrev = chainActive.Tip();
auto_ptr<CBlockTemplate> pblocktemplate(CreateNewBlock(chainparams, coinbaseScript->reserveScript));
if (!pblocktemplate.get())
{
LogPrintf("Error in BitcoinMiner: Keypool ran out, please call keypoolrefill before restarting the mining thread\n");
return;
}
CBlock *pblock = &pblocktemplate->block;
IncrementExtraNonce(pblock, pindexPrev, nExtraNonce);
LogPrintf("Running BitcoinMiner with %u transactions in block (%u bytes)\n", pblock->vtx.size(),
::GetSerializeSize(*pblock, SER_NETWORK, PROTOCOL_VERSION));
//
// Search
//
int64_t nStart = GetTime();
arith_uint256 hashTarget = arith_uint256().SetCompact(pblock->nBits);
uint256 hash;
uint32_t nNonce = 0;
while (true) {
// Check if something found
if (ScanHash(pblock, nNonce, &hash))
{
if (UintToArith256(hash) <= hashTarget)
{
// Found a solution
pblock->nNonce = nNonce;
assert(hash == pblock->GetHash());
SetThreadPriority(THREAD_PRIORITY_NORMAL);
LogPrintf("BitcoinMiner:\n");
LogPrintf("proof-of-work found \n hash: %s \ntarget: %s\n", hash.GetHex(), hashTarget.GetHex());
ProcessBlockFound(pblock, chainparams);
SetThreadPriority(THREAD_PRIORITY_LOWEST);
coinbaseScript->KeepScript();
// In regression test mode, stop mining after a block is found.
if (chainparams.MineBlocksOnDemand())
throw boost::thread_interrupted();
break;
}
}
// Check for stop or if block needs to be rebuilt
boost::this_thread::interruption_point();
// Regtest mode doesn't require peers
if (vNodes.empty() && chainparams.MiningRequiresPeers())
break;
if (nNonce >= 0xffff0000)
break;
if (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - nStart > 60)
break;
if (pindexPrev != chainActive.Tip())
break;
// Update nTime every few seconds
if (UpdateTime(pblock, chainparams.GetConsensus(), pindexPrev) < 0)
break; // Recreate the block if the clock has run backwards,
// so that we can use the correct time.
if (chainparams.GetConsensus().fPowAllowMinDifficultyBlocks)
{
// Changing pblock->nTime can change work required on testnet:
hashTarget.SetCompact(pblock->nBits);
}
}
}
}
catch (const boost::thread_interrupted&)
{
LogPrintf("BitcoinMiner terminated\n");
throw;
}
catch (const std::runtime_error &e)
{
LogPrintf("BitcoinMiner runtime error: %s\n", e.what());
return;
}
}
void GenerateBitcoins(bool fGenerate, int nThreads, const CChainParams& chainparams)
{
static boost::thread_group* minerThreads = NULL;
if (nThreads < 0)
nThreads = GetNumCores();
if (minerThreads != NULL)
{
minerThreads->interrupt_all();
delete minerThreads;
minerThreads = NULL;
}
if (nThreads == 0 || !fGenerate)
return;
minerThreads = new boost::thread_group();
for (int i = 0; i < nThreads; i++)
minerThreads->create_thread(boost::bind(&BitcoinMiner, boost::cref(chainparams)));
}