// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_MAIN_H
#define BITCOIN_MAIN_H
#if defined(HAVE_CONFIG_H)
#include "bitcoin-config.h"
#endif
#include "core.h"
#include "bignum.h"
#include "sync.h"
#include "net.h"
#include "script.h"
#include <list>
class CWallet;
class CBlock;
class CBlockIndex;
class CKeyItem;
class CReserveKey;
class CAddress;
class CInv;
class CNode;
struct CBlockIndexWorkComparator;
/** The maximum allowed size for a serialized block, in bytes (network rule) */
static const unsigned int MAX_BLOCK_SIZE = 1000000;
/** The maximum size for mined blocks */
static const unsigned int MAX_BLOCK_SIZE_GEN = MAX_BLOCK_SIZE/2;
/** The maximum size for transactions we're willing to relay/mine */
static const unsigned int MAX_STANDARD_TX_SIZE = MAX_BLOCK_SIZE_GEN/5;
/** The maximum allowed number of signature check operations in a block (network rule) */
static const unsigned int MAX_BLOCK_SIGOPS = MAX_BLOCK_SIZE/50;
/** The maximum number of orphan transactions kept in memory */
static const unsigned int MAX_ORPHAN_TRANSACTIONS = MAX_BLOCK_SIZE/100;
/** The maximum size of a blk?????.dat file (since 0.8) */
static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
/** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
/** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
/** Fake height value used in CCoins to signify they are only in the memory pool (since 0.8) */
static const unsigned int MEMPOOL_HEIGHT = 0x7FFFFFFF;
/** No amount larger than this (in satoshi) is valid */
static const int64 MAX_MONEY = 21000000 * COIN;
inline bool MoneyRange(int64 nValue) { return (nValue >= 0 && nValue <= MAX_MONEY); }
/** Coinbase transaction outputs can only be spent after this number of new blocks (network rule) */
static const int COINBASE_MATURITY = 100;
/** Threshold for nLockTime: below this value it is interpreted as block number, otherwise as UNIX timestamp. */
static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov 5 00:53:20 1985 UTC
/** Maximum number of script-checking threads allowed */
static const int MAX_SCRIPTCHECK_THREADS = 16;
/** Default amount of block size reserved for high-priority transactions (in bytes) */
static const int DEFAULT_BLOCK_PRIORITY_SIZE = 27000;
#ifdef USE_UPNP
static const int fHaveUPnP = true;
#else
static const int fHaveUPnP = false;
#endif
extern CScript COINBASE_FLAGS;
extern CCriticalSection cs_main;
extern std::map<uint256, CBlockIndex*> mapBlockIndex;
extern std::vector<CBlockIndex*> vBlockIndexByHeight;
extern std::set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid;
extern CBlockIndex* pindexGenesisBlock;
extern int nBestHeight;
extern uint256 nBestChainWork;
extern uint256 nBestInvalidWork;
extern uint256 hashBestChain;
extern CBlockIndex* pindexBest;
extern unsigned int nTransactionsUpdated;
extern uint64 nLastBlockTx;
extern uint64 nLastBlockSize;
extern const std::string strMessageMagic;
extern double dHashesPerSec;
extern int64 nHPSTimerStart;
extern int64 nTimeBestReceived;
extern CCriticalSection cs_setpwalletRegistered;
extern std::set<CWallet*> setpwalletRegistered;
extern bool fImporting;
extern bool fReindex;
extern bool fBenchmark;
extern int nScriptCheckThreads;
extern bool fTxIndex;
extern unsigned int nCoinCacheSize;
extern bool fHaveGUI;
// Settings
extern int64 nTransactionFee;
// Minimum disk space required - used in CheckDiskSpace()
static const uint64 nMinDiskSpace = 52428800;
class CReserveKey;
class CCoinsDB;
class CBlockTreeDB;
struct CDiskBlockPos;
class CCoins;
class CTxUndo;
class CCoinsView;
class CCoinsViewCache;
class CScriptCheck;
class CValidationState;
struct CBlockTemplate;
/** Register a wallet to receive updates from core */
void RegisterWallet(CWallet* pwalletIn);
/** Unregister a wallet from core */
void UnregisterWallet(CWallet* pwalletIn);
/** Unregister all wallets from core */
void UnregisterAllWallets();
/** Push an updated transaction to all registered wallets */
void SyncWithWallets(const uint256 &hash, const CTransaction& tx, const CBlock* pblock = NULL, bool fUpdate = false);
/** Register with a network node to receive its signals */
void RegisterNodeSignals(CNodeSignals& nodeSignals);
/** Unregister a network node */
void UnregisterNodeSignals(CNodeSignals& nodeSignals);
void PushGetBlocks(CNode* pnode, CBlockIndex* pindexBegin, uint256 hashEnd);
/** Process an incoming block */
bool ProcessBlock(CValidationState &state, CNode* pfrom, CBlock* pblock, CDiskBlockPos *dbp = NULL);
/** Check whether enough disk space is available for an incoming block */
bool CheckDiskSpace(uint64 nAdditionalBytes = 0);
/** Open a block file (blk?????.dat) */
FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly = false);
/** Open an undo file (rev?????.dat) */
FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly = false);
/** Import blocks from an external file */
bool LoadExternalBlockFile(FILE* fileIn, CDiskBlockPos *dbp = NULL);
/** Initialize a new block tree database + block data on disk */
bool InitBlockIndex();
/** Load the block tree and coins database from disk */
bool LoadBlockIndex();
/** Unload database information */
void UnloadBlockIndex();
/** Verify consistency of the block and coin databases */
bool VerifyDB(int nCheckLevel, int nCheckDepth);
/** Print the loaded block tree */
void PrintBlockTree();
/** Find a block by height in the currently-connected chain */
CBlockIndex* FindBlockByHeight(int nHeight);
/** Process protocol messages received from a given node */
bool ProcessMessages(CNode* pfrom);
/** Send queued protocol messages to be sent to a give node */
bool SendMessages(CNode* pto, bool fSendTrickle);
/** Run an instance of the script checking thread */
void ThreadScriptCheck();
/** Check whether a block hash satisfies the proof-of-work requirement specified by nBits */
bool CheckProofOfWork(uint256 hash, unsigned int nBits);
/** Calculate the minimum amount of work a received block needs, without knowing its direct parent */
unsigned int ComputeMinWork(unsigned int nBase, int64 nTime);
/** Get the number of active peers */
int GetNumBlocksOfPeers();
/** Check whether we are doing an initial block download (synchronizing from disk or network) */
bool IsInitialBlockDownload();
/** Format a string that describes several potential problems detected by the core */
std::string GetWarnings(std::string strFor);
/** Retrieve a transaction (from memory pool, or from disk, if possible) */
bool GetTransaction(const uint256 &hash, CTransaction &tx, uint256 &hashBlock, bool fAllowSlow = false);
/** Connect/disconnect blocks until pindexNew is the new tip of the active block chain */
bool SetBestChain(CValidationState &state, CBlockIndex* pindexNew);
/** Find the best known block, and make it the tip of the block chain */
bool ConnectBestBlock(CValidationState &state);
int64 GetBlockValue(int nHeight, int64 nFees);
unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHeader *pblock);
void UpdateTime(CBlockHeader& block, const CBlockIndex* pindexPrev);
/** Create a new block index entry for a given block hash */
CBlockIndex * InsertBlockIndex(uint256 hash);
/** Verify a signature */
bool VerifySignature(const CCoins& txFrom, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
/** Abort with a message */
bool AbortNode(const std::string &msg);
bool GetWalletFile(CWallet* pwallet, std::string &strWalletFileOut);
struct CDiskBlockPos
{
int nFile;
unsigned int nPos;
IMPLEMENT_SERIALIZE(
READWRITE(VARINT(nFile));
READWRITE(VARINT(nPos));
)
CDiskBlockPos() {
SetNull();
}
CDiskBlockPos(int nFileIn, unsigned int nPosIn) {
nFile = nFileIn;
nPos = nPosIn;
}
friend bool operator==(const CDiskBlockPos &a, const CDiskBlockPos &b) {
return (a.nFile == b.nFile && a.nPos == b.nPos);
}
friend bool operator!=(const CDiskBlockPos &a, const CDiskBlockPos &b) {
return !(a == b);
}
void SetNull() { nFile = -1; nPos = 0; }
bool IsNull() const { return (nFile == -1); }
};
struct CDiskTxPos : public CDiskBlockPos
{
unsigned int nTxOffset; // after header
IMPLEMENT_SERIALIZE(
READWRITE(*(CDiskBlockPos*)this);
READWRITE(VARINT(nTxOffset));
)
CDiskTxPos(const CDiskBlockPos &blockIn, unsigned int nTxOffsetIn) : CDiskBlockPos(blockIn.nFile, blockIn.nPos), nTxOffset(nTxOffsetIn) {
}
CDiskTxPos() {
SetNull();
}
void SetNull() {
CDiskBlockPos::SetNull();
nTxOffset = 0;
}
};
enum GetMinFee_mode
{
GMF_RELAY,
GMF_SEND,
};
int64 GetMinFee(const CTransaction& tx, bool fAllowFree, enum GetMinFee_mode mode);
//
// Check transaction inputs, and make sure any
// pay-to-script-hash transactions are evaluating IsStandard scripts
//
// Why bother? To avoid denial-of-service attacks; an attacker
// can submit a standard HASH... OP_EQUAL transaction,
// which will get accepted into blocks. The redemption
// script can be anything; an attacker could use a very
// expensive-to-check-upon-redemption script like:
// DUP CHECKSIG DROP ... repeated 100 times... OP_1
//
/** Check for standard transaction types
@param[in] mapInputs Map of previous transactions that have outputs we're spending
@return True if all inputs (scriptSigs) use only standard transaction forms
*/
bool AreInputsStandard(const CTransaction& tx, CCoinsViewCache& mapInputs);
/** Count ECDSA signature operations the old-fashioned (pre-0.6) way
@return number of sigops this transaction's outputs will produce when spent
@see CTransaction::FetchInputs
*/
unsigned int GetLegacySigOpCount(const CTransaction& tx);
/** Count ECDSA signature operations in pay-to-script-hash inputs.
@param[in] mapInputs Map of previous transactions that have outputs we're spending
@return maximum number of sigops required to validate this transaction's inputs
@see CTransaction::FetchInputs
*/
unsigned int GetP2SHSigOpCount(const CTransaction& tx, CCoinsViewCache& mapInputs);
inline bool AllowFree(double dPriority)
{
// Large (in bytes) low-priority (new, small-coin) transactions
// need a fee.
return dPriority > COIN * 144 / 250;
}
// Check whether all inputs of this transaction are valid (no double spends, scripts & sigs, amounts)
// This does not modify the UTXO set. If pvChecks is not NULL, script checks are pushed onto it
// instead of being performed inline.
bool CheckInputs(const CTransaction& tx, CValidationState &state, CCoinsViewCache &view, bool fScriptChecks = true,
unsigned int flags = SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC,
std::vector<CScriptCheck> *pvChecks = NULL);
// Apply the effects of this transaction on the UTXO set represented by view
void UpdateCoins(const CTransaction& tx, CValidationState &state, CCoinsViewCache &inputs, CTxUndo &txundo, int nHeight, const uint256 &txhash);
// Context-independent validity checks
bool CheckTransaction(const CTransaction& tx, CValidationState& state);
/** Check for standard transaction types
@return True if all outputs (scriptPubKeys) use only standard transaction forms
*/
bool IsStandardTx(const CTransaction& tx, std::string& reason);
bool IsFinalTx(const CTransaction &tx, int nBlockHeight = 0, int64 nBlockTime = 0);
/** Amount of bitcoins spent by the transaction.
@return sum of all outputs (note: does not include fees)
*/
int64 GetValueOut(const CTransaction& tx);
/** Undo information for a CBlock */
class CBlockUndo
{
public:
std::vector<CTxUndo> vtxundo; // for all but the coinbase
IMPLEMENT_SERIALIZE(
READWRITE(vtxundo);
)
bool WriteToDisk(CDiskBlockPos &pos, const uint256 &hashBlock)
{
// Open history file to append
CAutoFile fileout = CAutoFile(OpenUndoFile(pos), SER_DISK, CLIENT_VERSION);
if (!fileout)
return error("CBlockUndo::WriteToDisk() : OpenUndoFile failed");
// Write index header
unsigned int nSize = fileout.GetSerializeSize(*this);
fileout << FLATDATA(Params().MessageStart()) << nSize;
// Write undo data
long fileOutPos = ftell(fileout);
if (fileOutPos < 0)
return error("CBlockUndo::WriteToDisk() : ftell failed");
pos.nPos = (unsigned int)fileOutPos;
fileout << *this;
// calculate & write checksum
CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION);
hasher << hashBlock;
hasher << *this;
fileout << hasher.GetHash();
// Flush stdio buffers and commit to disk before returning
fflush(fileout);
if (!IsInitialBlockDownload())
FileCommit(fileout);
return true;
}
bool ReadFromDisk(const CDiskBlockPos &pos, const uint256 &hashBlock)
{
// Open history file to read
CAutoFile filein = CAutoFile(OpenUndoFile(pos, true), SER_DISK, CLIENT_VERSION);
if (!filein)
return error("CBlockUndo::ReadFromDisk() : OpenBlockFile failed");
// Read block
uint256 hashChecksum;
try {
filein >> *this;
filein >> hashChecksum;
}
catch (std::exception &e) {
return error("%s() : deserialize or I/O error", __PRETTY_FUNCTION__);
}
// Verify checksum
CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION);
hasher << hashBlock;
hasher << *this;
if (hashChecksum != hasher.GetHash())
return error("CBlockUndo::ReadFromDisk() : checksum mismatch");
return true;
}
};
/** Closure representing one script verification
* Note that this stores references to the spending transaction */
class CScriptCheck
{
private:
CScript scriptPubKey;
const CTransaction *ptxTo;
unsigned int nIn;
unsigned int nFlags;
int nHashType;
public:
CScriptCheck() {}
CScriptCheck(const CCoins& txFromIn, const CTransaction& txToIn, unsigned int nInIn, unsigned int nFlagsIn, int nHashTypeIn) :
scriptPubKey(txFromIn.vout[txToIn.vin[nInIn].prevout.n].scriptPubKey),
ptxTo(&txToIn), nIn(nInIn), nFlags(nFlagsIn), nHashType(nHashTypeIn) { }
bool operator()() const;
void swap(CScriptCheck &check) {
scriptPubKey.swap(check.scriptPubKey);
std::swap(ptxTo, check.ptxTo);
std::swap(nIn, check.nIn);
std::swap(nFlags, check.nFlags);
std::swap(nHashType, check.nHashType);
}
};
/** A transaction with a merkle branch linking it to the block chain. */
class CMerkleTx : public CTransaction
{
public:
uint256 hashBlock;
std::vector<uint256> vMerkleBranch;
int nIndex;
// memory only
mutable bool fMerkleVerified;
CMerkleTx()
{
Init();
}
CMerkleTx(const CTransaction& txIn) : CTransaction(txIn)
{
Init();
}
void Init()
{
hashBlock = 0;
nIndex = -1;
fMerkleVerified = false;
}
IMPLEMENT_SERIALIZE
(
nSerSize += SerReadWrite(s, *(CTransaction*)this, nType, nVersion, ser_action);
nVersion = this->nVersion;
READWRITE(hashBlock);
READWRITE(vMerkleBranch);
READWRITE(nIndex);
)
int SetMerkleBranch(const CBlock* pblock=NULL);
int GetDepthInMainChain(CBlockIndex* &pindexRet) const;
int GetDepthInMainChain() const { CBlockIndex *pindexRet; return GetDepthInMainChain(pindexRet); }
bool IsInMainChain() const { return GetDepthInMainChain() > 0; }
int GetBlocksToMaturity() const;
bool AcceptToMemoryPool(bool fLimitFree=true);
};
/** Data structure that represents a partial merkle tree.
*
* It respresents a subset of the txid's of a known block, in a way that
* allows recovery of the list of txid's and the merkle root, in an
* authenticated way.
*
* The encoding works as follows: we traverse the tree in depth-first order,
* storing a bit for each traversed node, signifying whether the node is the
* parent of at least one matched leaf txid (or a matched txid itself). In
* case we are at the leaf level, or this bit is 0, its merkle node hash is
* stored, and its children are not explorer further. Otherwise, no hash is
* stored, but we recurse into both (or the only) child branch. During
* decoding, the same depth-first traversal is performed, consuming bits and
* hashes as they written during encoding.
*
* The serialization is fixed and provides a hard guarantee about the
* encoded size:
*
* SIZE <= 10 + ceil(32.25*N)
*
* Where N represents the number of leaf nodes of the partial tree. N itself
* is bounded by:
*
* N <= total_transactions
* N <= 1 + matched_transactions*tree_height
*
* The serialization format:
* - uint32 total_transactions (4 bytes)
* - varint number of hashes (1-3 bytes)
* - uint256[] hashes in depth-first order (<= 32*N bytes)
* - varint number of bytes of flag bits (1-3 bytes)
* - byte[] flag bits, packed per 8 in a byte, least significant bit first (<= 2*N-1 bits)
* The size constraints follow from this.
*/
class CPartialMerkleTree
{
protected:
// the total number of transactions in the block
unsigned int nTransactions;
// node-is-parent-of-matched-txid bits
std::vector<bool> vBits;
// txids and internal hashes
std::vector<uint256> vHash;
// flag set when encountering invalid data
bool fBad;
// helper function to efficiently calculate the number of nodes at given height in the merkle tree
unsigned int CalcTreeWidth(int height) {
return (nTransactions+(1 << height)-1) >> height;
}
// calculate the hash of a node in the merkle tree (at leaf level: the txid's themself)
uint256 CalcHash(int height, unsigned int pos, const std::vector<uint256> &vTxid);
// recursive function that traverses tree nodes, storing the data as bits and hashes
void TraverseAndBuild(int height, unsigned int pos, const std::vector<uint256> &vTxid, const std::vector<bool> &vMatch);
// recursive function that traverses tree nodes, consuming the bits and hashes produced by TraverseAndBuild.
// it returns the hash of the respective node.
uint256 TraverseAndExtract(int height, unsigned int pos, unsigned int &nBitsUsed, unsigned int &nHashUsed, std::vector<uint256> &vMatch);
public:
// serialization implementation
IMPLEMENT_SERIALIZE(
READWRITE(nTransactions);
READWRITE(vHash);
std::vector<unsigned char> vBytes;
if (fRead) {
READWRITE(vBytes);
CPartialMerkleTree &us = *(const_cast<CPartialMerkleTree*>(this));
us.vBits.resize(vBytes.size() * 8);
for (unsigned int p = 0; p < us.vBits.size(); p++)
us.vBits[p] = (vBytes[p / 8] & (1 << (p % 8))) != 0;
us.fBad = false;
} else {
vBytes.resize((vBits.size()+7)/8);
for (unsigned int p = 0; p < vBits.size(); p++)
vBytes[p / 8] |= vBits[p] << (p % 8);
READWRITE(vBytes);
}
)
// Construct a partial merkle tree from a list of transaction id's, and a mask that selects a subset of them
CPartialMerkleTree(const std::vector<uint256> &vTxid, const std::vector<bool> &vMatch);
CPartialMerkleTree();
// extract the matching txid's represented by this partial merkle tree.
// returns the merkle root, or 0 in case of failure
uint256 ExtractMatches(std::vector<uint256> &vMatch);
};
/** Functions for disk access for blocks */
bool WriteBlockToDisk(CBlock& block, CDiskBlockPos& pos);
bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos);
bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex);
/** Functions for validating blocks and updating the block tree */
/** Undo the effects of this block (with given index) on the UTXO set represented by coins.
* In case pfClean is provided, operation will try to be tolerant about errors, and *pfClean
* will be true if no problems were found. Otherwise, the return value will be false in case
* of problems. Note that in any case, coins may be modified. */
bool DisconnectBlock(CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& coins, bool* pfClean = NULL);
// Apply the effects of this block (with given index) on the UTXO set represented by coins
bool ConnectBlock(CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& coins, bool fJustCheck = false);
// Add this block to the block index, and if necessary, switch the active block chain to this
bool AddToBlockIndex(CBlock& block, CValidationState& state, const CDiskBlockPos& pos);
// Context-independent validity checks
bool CheckBlock(const CBlock& block, CValidationState& state, bool fCheckPOW = true, bool fCheckMerkleRoot = true);
// Store block on disk
// if dbp is provided, the file is known to already reside on disk
bool AcceptBlock(CBlock& block, CValidationState& state, CDiskBlockPos* dbp = NULL);
class CBlockFileInfo
{
public:
unsigned int nBlocks; // number of blocks stored in file
unsigned int nSize; // number of used bytes of block file
unsigned int nUndoSize; // number of used bytes in the undo file
unsigned int nHeightFirst; // lowest height of block in file
unsigned int nHeightLast; // highest height of block in file
uint64 nTimeFirst; // earliest time of block in file
uint64 nTimeLast; // latest time of block in file
IMPLEMENT_SERIALIZE(
READWRITE(VARINT(nBlocks));
READWRITE(VARINT(nSize));
READWRITE(VARINT(nUndoSize));
READWRITE(VARINT(nHeightFirst));
READWRITE(VARINT(nHeightLast));
READWRITE(VARINT(nTimeFirst));
READWRITE(VARINT(nTimeLast));
)
void SetNull() {
nBlocks = 0;
nSize = 0;
nUndoSize = 0;
nHeightFirst = 0;
nHeightLast = 0;
nTimeFirst = 0;
nTimeLast = 0;
}
CBlockFileInfo() {
SetNull();
}
std::string ToString() const {
return strprintf("CBlockFileInfo(blocks=%u, size=%u, heights=%u...%u, time=%s...%s)", nBlocks, nSize, nHeightFirst, nHeightLast, DateTimeStrFormat("%Y-%m-%d", nTimeFirst).c_str(), DateTimeStrFormat("%Y-%m-%d", nTimeLast).c_str());
}
// update statistics (does not update nSize)
void AddBlock(unsigned int nHeightIn, uint64 nTimeIn) {
if (nBlocks==0 || nHeightFirst > nHeightIn)
nHeightFirst = nHeightIn;
if (nBlocks==0 || nTimeFirst > nTimeIn)
nTimeFirst = nTimeIn;
nBlocks++;
if (nHeightIn > nHeightFirst)
nHeightLast = nHeightIn;
if (nTimeIn > nTimeLast)
nTimeLast = nTimeIn;
}
};
extern CCriticalSection cs_LastBlockFile;
extern CBlockFileInfo infoLastBlockFile;
extern int nLastBlockFile;
enum BlockStatus {
BLOCK_VALID_UNKNOWN = 0,
BLOCK_VALID_HEADER = 1, // parsed, version ok, hash satisfies claimed PoW, 1 <= vtx count <= max, timestamp not in future
BLOCK_VALID_TREE = 2, // parent found, difficulty matches, timestamp >= median previous, checkpoint
BLOCK_VALID_TRANSACTIONS = 3, // only first tx is coinbase, 2 <= coinbase input script length <= 100, transactions valid, no duplicate txids, sigops, size, merkle root
BLOCK_VALID_CHAIN = 4, // outputs do not overspend inputs, no double spends, coinbase output ok, immature coinbase spends, BIP30
BLOCK_VALID_SCRIPTS = 5, // scripts/signatures ok
BLOCK_VALID_MASK = 7,
BLOCK_HAVE_DATA = 8, // full block available in blk*.dat
BLOCK_HAVE_UNDO = 16, // undo data available in rev*.dat
BLOCK_HAVE_MASK = 24,
BLOCK_FAILED_VALID = 32, // stage after last reached validness failed
BLOCK_FAILED_CHILD = 64, // descends from failed block
BLOCK_FAILED_MASK = 96
};
/** The block chain is a tree shaped structure starting with the
* genesis block at the root, with each block potentially having multiple
* candidates to be the next block. A blockindex may have multiple pprev pointing
* to it, but at most one of them can be part of the currently active branch.
*/
class CBlockIndex
{
public:
// pointer to the hash of the block, if any. memory is owned by this CBlockIndex
const uint256* phashBlock;
// pointer to the index of the predecessor of this block
CBlockIndex* pprev;
// height of the entry in the chain. The genesis block has height 0
int nHeight;
// Which # file this block is stored in (blk?????.dat)
int nFile;
// Byte offset within blk?????.dat where this block's data is stored
unsigned int nDataPos;
// Byte offset within rev?????.dat where this block's undo data is stored
unsigned int nUndoPos;
// (memory only) Total amount of work (expected number of hashes) in the chain up to and including this block
uint256 nChainWork;
// Number of transactions in this block.
// Note: in a potential headers-first mode, this number cannot be relied upon
unsigned int nTx;
// (memory only) Number of transactions in the chain up to and including this block
unsigned int nChainTx; // change to 64-bit type when necessary; won't happen before 2030
// Verification status of this block. See enum BlockStatus
unsigned int nStatus;
// block header
int nVersion;
uint256 hashMerkleRoot;
unsigned int nTime;
unsigned int nBits;
unsigned int nNonce;
CBlockIndex()
{
phashBlock = NULL;
pprev = NULL;
nHeight = 0;
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
nChainWork = 0;
nTx = 0;
nChainTx = 0;
nStatus = 0;
nVersion = 0;
hashMerkleRoot = 0;
nTime = 0;
nBits = 0;
nNonce = 0;
}
CBlockIndex(CBlockHeader& block)
{
phashBlock = NULL;
pprev = NULL;
nHeight = 0;
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
nChainWork = 0;
nTx = 0;
nChainTx = 0;
nStatus = 0;
nVersion = block.nVersion;
hashMerkleRoot = block.hashMerkleRoot;
nTime = block.nTime;
nBits = block.nBits;
nNonce = block.nNonce;
}
CDiskBlockPos GetBlockPos() const {
CDiskBlockPos ret;
if (nStatus & BLOCK_HAVE_DATA) {
ret.nFile = nFile;
ret.nPos = nDataPos;
}
return ret;
}
CDiskBlockPos GetUndoPos() const {
CDiskBlockPos ret;
if (nStatus & BLOCK_HAVE_UNDO) {
ret.nFile = nFile;
ret.nPos = nUndoPos;
}
return ret;
}
CBlockHeader GetBlockHeader() const
{
CBlockHeader block;
block.nVersion = nVersion;
if (pprev)
block.hashPrevBlock = pprev->GetBlockHash();
block.hashMerkleRoot = hashMerkleRoot;
block.nTime = nTime;
block.nBits = nBits;
block.nNonce = nNonce;
return block;
}
uint256 GetBlockHash() const
{
return *phashBlock;
}
int64 GetBlockTime() const
{
return (int64)nTime;
}
CBigNum GetBlockWork() const
{
CBigNum bnTarget;
bnTarget.SetCompact(nBits);
if (bnTarget <= 0)
return 0;
return (CBigNum(1)<<256) / (bnTarget+1);
}
bool IsInMainChain() const
{
return nHeight < (int)vBlockIndexByHeight.size() && vBlockIndexByHeight[nHeight] == this;
}
CBlockIndex *GetNextInMainChain() const {
return nHeight+1 >= (int)vBlockIndexByHeight.size() ? NULL : vBlockIndexByHeight[nHeight+1];
}
bool CheckIndex() const
{
return CheckProofOfWork(GetBlockHash(), nBits);
}
enum { nMedianTimeSpan=11 };
int64 GetMedianTimePast() const
{
int64 pmedian[nMedianTimeSpan];
int64* pbegin = &pmedian[nMedianTimeSpan];
int64* pend = &pmedian[nMedianTimeSpan];
const CBlockIndex* pindex = this;
for (int i = 0; i < nMedianTimeSpan && pindex; i++, pindex = pindex->pprev)
*(--pbegin) = pindex->GetBlockTime();
std::sort(pbegin, pend);
return pbegin[(pend - pbegin)/2];
}
int64 GetMedianTime() const
{
const CBlockIndex* pindex = this;
for (int i = 0; i < nMedianTimeSpan/2; i++)
{
if (!pindex->GetNextInMainChain())
return GetBlockTime();
pindex = pindex->GetNextInMainChain();
}
return pindex->GetMedianTimePast();
}
/**
* Returns true if there are nRequired or more blocks of minVersion or above
* in the last nToCheck blocks, starting at pstart and going backwards.
*/
static bool IsSuperMajority(int minVersion, const CBlockIndex* pstart,
unsigned int nRequired, unsigned int nToCheck);
std::string ToString() const
{
return strprintf("CBlockIndex(pprev=%p, pnext=%p, nHeight=%d, merkle=%s, hashBlock=%s)",
pprev, GetNextInMainChain(), nHeight,
hashMerkleRoot.ToString().c_str(),
GetBlockHash().ToString().c_str());
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
struct CBlockIndexWorkComparator
{
bool operator()(CBlockIndex *pa, CBlockIndex *pb) {
if (pa->nChainWork > pb->nChainWork) return false;
if (pa->nChainWork < pb->nChainWork) return true;
if (pa->GetBlockHash() < pb->GetBlockHash()) return false;
if (pa->GetBlockHash() > pb->GetBlockHash()) return true;
return false; // identical blocks
}
};
/** Used to marshal pointers into hashes for db storage. */
class CDiskBlockIndex : public CBlockIndex
{
public:
uint256 hashPrev;
CDiskBlockIndex() {
hashPrev = 0;
}
explicit CDiskBlockIndex(CBlockIndex* pindex) : CBlockIndex(*pindex) {
hashPrev = (pprev ? pprev->GetBlockHash() : 0);
}
IMPLEMENT_SERIALIZE
(
if (!(nType & SER_GETHASH))
READWRITE(VARINT(nVersion));
READWRITE(VARINT(nHeight));
READWRITE(VARINT(nStatus));
READWRITE(VARINT(nTx));
if (nStatus & (BLOCK_HAVE_DATA | BLOCK_HAVE_UNDO))
READWRITE(VARINT(nFile));
if (nStatus & BLOCK_HAVE_DATA)
READWRITE(VARINT(nDataPos));
if (nStatus & BLOCK_HAVE_UNDO)
READWRITE(VARINT(nUndoPos));
// block header
READWRITE(this->nVersion);
READWRITE(hashPrev);
READWRITE(hashMerkleRoot);
READWRITE(nTime);
READWRITE(nBits);
READWRITE(nNonce);
)
uint256 GetBlockHash() const
{
CBlockHeader block;
block.nVersion = nVersion;
block.hashPrevBlock = hashPrev;
block.hashMerkleRoot = hashMerkleRoot;
block.nTime = nTime;
block.nBits = nBits;
block.nNonce = nNonce;
return block.GetHash();
}
std::string ToString() const
{
std::string str = "CDiskBlockIndex(";
str += CBlockIndex::ToString();
str += strprintf("\n hashBlock=%s, hashPrev=%s)",
GetBlockHash().ToString().c_str(),
hashPrev.ToString().c_str());
return str;
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
/** Capture information about block/transaction validation */
class CValidationState {
private:
enum mode_state {
MODE_VALID, // everything ok
MODE_INVALID, // network rule violation (DoS value may be set)
MODE_ERROR, // run-time error
} mode;
int nDoS;
public:
CValidationState() : mode(MODE_VALID), nDoS(0) {}
bool DoS(int level, bool ret = false) {
if (mode == MODE_ERROR)
return ret;
nDoS += level;
mode = MODE_INVALID;
return ret;
}
bool Invalid(bool ret = false) {
return DoS(0, ret);
}
bool Error() {
mode = MODE_ERROR;
return false;
}
bool Abort(const std::string &msg) {
AbortNode(msg);
return Error();
}
bool IsValid() {
return mode == MODE_VALID;
}
bool IsInvalid() {
return mode == MODE_INVALID;
}
bool IsError() {
return mode == MODE_ERROR;
}
bool IsInvalid(int &nDoSOut) {
if (IsInvalid()) {
nDoSOut = nDoS;
return true;
}
return false;
}
};
/** Describes a place in the block chain to another node such that if the
* other node doesn't have the same branch, it can find a recent common trunk.
* The further back it is, the further before the fork it may be.
*/
class CBlockLocator
{
protected:
std::vector<uint256> vHave;
public:
CBlockLocator() {}
explicit CBlockLocator(const CBlockIndex* pindex)
{
Set(pindex);
}
explicit CBlockLocator(uint256 hashBlock);
CBlockLocator(const std::vector<uint256>& vHaveIn)
{
vHave = vHaveIn;
}
IMPLEMENT_SERIALIZE
(
if (!(nType & SER_GETHASH))
READWRITE(nVersion);
READWRITE(vHave);
)
void SetNull()
{
vHave.clear();
}
bool IsNull()
{
return vHave.empty();
}
/** Given a block initialises the locator to that point in the chain. */
void Set(const CBlockIndex* pindex);
/** Returns the distance in blocks this locator is from our chain head. */
int GetDistanceBack();
/** Returns the first best-chain block the locator contains. */
CBlockIndex* GetBlockIndex();
/** Returns the hash of the first best chain block the locator contains. */
uint256 GetBlockHash();
/** Returns the height of the first best chain block the locator has. */
int GetHeight();
};
class CTxMemPool
{
public:
static bool fChecks;
mutable CCriticalSection cs;
std::map<uint256, CTransaction> mapTx;
std::map<COutPoint, CInPoint> mapNextTx;
bool accept(CValidationState &state, const CTransaction &tx, bool fLimitFree, bool* pfMissingInputs);
bool addUnchecked(const uint256& hash, const CTransaction &tx);
bool remove(const CTransaction &tx, bool fRecursive = false);
bool removeConflicts(const CTransaction &tx);
void clear();
void queryHashes(std::vector<uint256>& vtxid);
void pruneSpent(const uint256& hash, CCoins &coins);
void check(CCoinsViewCache *pcoins) const;
unsigned long size()
{
LOCK(cs);
return mapTx.size();
}
bool exists(uint256 hash)
{
return (mapTx.count(hash) != 0);
}
CTransaction& lookup(uint256 hash)
{
return mapTx[hash];
}
};
extern CTxMemPool mempool;
struct CCoinsStats
{
int nHeight;
uint256 hashBlock;
uint64 nTransactions;
uint64 nTransactionOutputs;
uint64 nSerializedSize;
uint256 hashSerialized;
int64 nTotalAmount;
CCoinsStats() : nHeight(0), hashBlock(0), nTransactions(0), nTransactionOutputs(0), nSerializedSize(0), hashSerialized(0), nTotalAmount(0) {}
};
/** Abstract view on the open txout dataset. */
class CCoinsView
{
public:
// Retrieve the CCoins (unspent transaction outputs) for a given txid
virtual bool GetCoins(const uint256 &txid, CCoins &coins);
// Modify the CCoins for a given txid
virtual bool SetCoins(const uint256 &txid, const CCoins &coins);
// Just check whether we have data for a given txid.
// This may (but cannot always) return true for fully spent transactions
virtual bool HaveCoins(const uint256 &txid);
// Retrieve the block index whose state this CCoinsView currently represents
virtual CBlockIndex *GetBestBlock();
// Modify the currently active block index
virtual bool SetBestBlock(CBlockIndex *pindex);
// Do a bulk modification (multiple SetCoins + one SetBestBlock)
virtual bool BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex);
// Calculate statistics about the unspent transaction output set
virtual bool GetStats(CCoinsStats &stats);
// As we use CCoinsViews polymorphically, have a virtual destructor
virtual ~CCoinsView() {}
};
/** CCoinsView backed by another CCoinsView */
class CCoinsViewBacked : public CCoinsView
{
protected:
CCoinsView *base;
public:
CCoinsViewBacked(CCoinsView &viewIn);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
CBlockIndex *GetBestBlock();
bool SetBestBlock(CBlockIndex *pindex);
void SetBackend(CCoinsView &viewIn);
bool BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex);
bool GetStats(CCoinsStats &stats);
};
/** CCoinsView that adds a memory cache for transactions to another CCoinsView */
class CCoinsViewCache : public CCoinsViewBacked
{
protected:
CBlockIndex *pindexTip;
std::map<uint256,CCoins> cacheCoins;
public:
CCoinsViewCache(CCoinsView &baseIn, bool fDummy = false);
// Standard CCoinsView methods
bool GetCoins(const uint256 &txid, CCoins &coins);
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
CBlockIndex *GetBestBlock();
bool SetBestBlock(CBlockIndex *pindex);
bool BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex);
// Return a modifiable reference to a CCoins. Check HaveCoins first.
// Many methods explicitly require a CCoinsViewCache because of this method, to reduce
// copying.
CCoins &GetCoins(const uint256 &txid);
// Push the modifications applied to this cache to its base.
// Failure to call this method before destruction will cause the changes to be forgotten.
bool Flush();
// Calculate the size of the cache (in number of transactions)
unsigned int GetCacheSize();
/** Amount of bitcoins coming in to a transaction
Note that lightweight clients may not know anything besides the hash of previous transactions,
so may not be able to calculate this.
@param[in] tx transaction for which we are checking input total
@return Sum of value of all inputs (scriptSigs)
@see CTransaction::FetchInputs
*/
int64 GetValueIn(const CTransaction& tx);
// Check whether all prevouts of the transaction are present in the UTXO set represented by this view
bool HaveInputs(const CTransaction& tx);
const CTxOut &GetOutputFor(const CTxIn& input);
private:
std::map<uint256,CCoins>::iterator FetchCoins(const uint256 &txid);
};
/** CCoinsView that brings transactions from a memorypool into view.
It does not check for spendings by memory pool transactions. */
class CCoinsViewMemPool : public CCoinsViewBacked
{
protected:
CTxMemPool &mempool;
public:
CCoinsViewMemPool(CCoinsView &baseIn, CTxMemPool &mempoolIn);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool HaveCoins(const uint256 &txid);
};
/** Global variable that points to the active CCoinsView (protected by cs_main) */
extern CCoinsViewCache *pcoinsTip;
/** Global variable that points to the active block tree (protected by cs_main) */
extern CBlockTreeDB *pblocktree;
struct CBlockTemplate
{
CBlock block;
std::vector<int64_t> vTxFees;
std::vector<int64_t> vTxSigOps;
};
/** Used to relay blocks as header + vector<merkle branch>
* to filtered nodes.
*/
class CMerkleBlock
{
public:
// Public only for unit testing
CBlockHeader header;
CPartialMerkleTree txn;
public:
// Public only for unit testing and relay testing
// (not relayed)
std::vector<std::pair<unsigned int, uint256> > vMatchedTxn;
// Create from a CBlock, filtering transactions according to filter
// Note that this will call IsRelevantAndUpdate on the filter for each transaction,
// thus the filter will likely be modified.
CMerkleBlock(const CBlock& block, CBloomFilter& filter);
IMPLEMENT_SERIALIZE
(
READWRITE(header);
READWRITE(txn);
)
};
#endif