Community driven twister-core
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

1969 lines
59 KiB

// 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
#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 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 number of entries in an 'inv' protocol message */
static const unsigned int MAX_INV_SZ = 50000;
/** 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;
/** Fees smaller than this (in satoshi) are considered zero fee (for transaction creation) */
static const int64 MIN_TX_FEE = 50000;
/** Fees smaller than this (in satoshi) are considered zero fee (for relaying) */
static const int64 MIN_RELAY_TX_FEE = 10000;
/** 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
#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::set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid;
extern uint256 hashGenesisBlock;
extern CBlockIndex* pindexGenesisBlock;
extern int nBestHeight;
extern CBigNum bnBestChainWork;
extern CBigNum bnBestInvalidWork;
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 unsigned char pchMessageStart[4];
extern bool fImporting;
extern bool fReindex;
extern unsigned int nCoinCacheSize;
// Settings
extern int64 nTransactionFee;
// Minimum disk space required - used in CheckDiskSpace()
static const uint64 nMinDiskSpace = 52428800;
class CReserveKey;
class CCoinsDB;
class CBlockTreeDB;
class CDiskBlockPos;
class CCoins;
class CTxUndo;
class CCoinsView;
class CCoinsViewCache;
/** Register a wallet to receive updates from core */
void RegisterWallet(CWallet* pwalletIn);
/** Unregister a wallet from core */
void UnregisterWallet(CWallet* pwalletIn);
/** Push an updated transaction to all registered wallets */
void SyncWithWallets(const uint256 &hash, const CTransaction& tx, const CBlock* pblock = NULL, bool fUpdate = false);
/** Process an incoming block */
bool ProcessBlock(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);
/** Load the block tree and coins database from disk */
bool LoadBlockIndex();
/** 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 the importer thread, which deals with reindexing, loading bootstrap.dat, and whatever is passed to -loadblock */
void ThreadImport(void *parg);
/** Run the miner threads */
void GenerateBitcoins(bool fGenerate, CWallet* pwallet);
/** Generate a new block, without valid proof-of-work */
CBlock* CreateNewBlock(CReserveKey& reservekey);
/** Modify the extranonce in a block */
void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& nExtraNonce);
/** Do mining precalculation */
void FormatHashBuffers(CBlock* pblock, char* pmidstate, char* pdata, char* phash1);
/** Check mined block */
bool CheckWork(CBlock* pblock, CWallet& wallet, CReserveKey& reservekey);
/** 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 doin an inital 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(CBlockIndex* pindexNew);
/** Find the best known block, and make it the tip of the block chain */
bool ConnectBestBlock();
/** Create a new block index entry for a given block hash */
CBlockIndex * InsertBlockIndex(uint256 hash);
static inline std::string BlockHashStr(const uint256& hash)
{
return hash.ToString();
}
bool GetWalletFile(CWallet* pwallet, std::string &strWalletFileOut);
class CDiskBlockPos
{
public:
int nFile;
unsigned int nPos;
IMPLEMENT_SERIALIZE(
READWRITE(VARINT(nFile));
READWRITE(VARINT(nPos));
)
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); }
};
/** An inpoint - a combination of a transaction and an index n into its vin */
class CInPoint
{
public:
CTransaction* ptx;
unsigned int n;
CInPoint() { SetNull(); }
CInPoint(CTransaction* ptxIn, unsigned int nIn) { ptx = ptxIn; n = nIn; }
void SetNull() { ptx = NULL; n = (unsigned int) -1; }
bool IsNull() const { return (ptx == NULL && n == (unsigned int) -1); }
};
/** An outpoint - a combination of a transaction hash and an index n into its vout */
class COutPoint
{
public:
uint256 hash;
unsigned int n;
COutPoint() { SetNull(); }
COutPoint(uint256 hashIn, unsigned int nIn) { hash = hashIn; n = nIn; }
IMPLEMENT_SERIALIZE( READWRITE(FLATDATA(*this)); )
void SetNull() { hash = 0; n = (unsigned int) -1; }
bool IsNull() const { return (hash == 0 && n == (unsigned int) -1); }
friend bool operator<(const COutPoint& a, const COutPoint& b)
{
return (a.hash < b.hash || (a.hash == b.hash && a.n < b.n));
}
friend bool operator==(const COutPoint& a, const COutPoint& b)
{
return (a.hash == b.hash && a.n == b.n);
}
friend bool operator!=(const COutPoint& a, const COutPoint& b)
{
return !(a == b);
}
std::string ToString() const
{
return strprintf("COutPoint(%s, %u)", hash.ToString().substr(0,10).c_str(), n);
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
/** An input of a transaction. It contains the location of the previous
* transaction's output that it claims and a signature that matches the
* output's public key.
*/
class CTxIn
{
public:
COutPoint prevout;
CScript scriptSig;
unsigned int nSequence;
CTxIn()
{
nSequence = std::numeric_limits<unsigned int>::max();
}
explicit CTxIn(COutPoint prevoutIn, CScript scriptSigIn=CScript(), unsigned int nSequenceIn=std::numeric_limits<unsigned int>::max())
{
prevout = prevoutIn;
scriptSig = scriptSigIn;
nSequence = nSequenceIn;
}
CTxIn(uint256 hashPrevTx, unsigned int nOut, CScript scriptSigIn=CScript(), unsigned int nSequenceIn=std::numeric_limits<unsigned int>::max())
{
prevout = COutPoint(hashPrevTx, nOut);
scriptSig = scriptSigIn;
nSequence = nSequenceIn;
}
IMPLEMENT_SERIALIZE
(
READWRITE(prevout);
READWRITE(scriptSig);
READWRITE(nSequence);
)
bool IsFinal() const
{
return (nSequence == std::numeric_limits<unsigned int>::max());
}
friend bool operator==(const CTxIn& a, const CTxIn& b)
{
return (a.prevout == b.prevout &&
a.scriptSig == b.scriptSig &&
a.nSequence == b.nSequence);
}
friend bool operator!=(const CTxIn& a, const CTxIn& b)
{
return !(a == b);
}
std::string ToString() const
{
std::string str;
str += "CTxIn(";
str += prevout.ToString();
if (prevout.IsNull())
str += strprintf(", coinbase %s", HexStr(scriptSig).c_str());
else
str += strprintf(", scriptSig=%s", scriptSig.ToString().substr(0,24).c_str());
if (nSequence != std::numeric_limits<unsigned int>::max())
str += strprintf(", nSequence=%u", nSequence);
str += ")";
return str;
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
/** An output of a transaction. It contains the public key that the next input
* must be able to sign with to claim it.
*/
class CTxOut
{
public:
int64 nValue;
CScript scriptPubKey;
CTxOut()
{
SetNull();
}
CTxOut(int64 nValueIn, CScript scriptPubKeyIn)
{
nValue = nValueIn;
scriptPubKey = scriptPubKeyIn;
}
IMPLEMENT_SERIALIZE
(
READWRITE(nValue);
READWRITE(scriptPubKey);
)
void SetNull()
{
nValue = -1;
scriptPubKey.clear();
}
bool IsNull() const
{
return (nValue == -1);
}
uint256 GetHash() const
{
return SerializeHash(*this);
}
friend bool operator==(const CTxOut& a, const CTxOut& b)
{
return (a.nValue == b.nValue &&
a.scriptPubKey == b.scriptPubKey);
}
friend bool operator!=(const CTxOut& a, const CTxOut& b)
{
return !(a == b);
}
std::string ToString() const
{
if (scriptPubKey.size() < 6)
return "CTxOut(error)";
return strprintf("CTxOut(nValue=%"PRI64d".%08"PRI64d", scriptPubKey=%s)", nValue / COIN, nValue % COIN, scriptPubKey.ToString().substr(0,30).c_str());
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
enum GetMinFee_mode
{
GMF_BLOCK,
GMF_RELAY,
GMF_SEND,
};
// Modes for script/signature checking
enum CheckSig_mode
{
CS_NEVER, // never validate scripts
CS_AFTER_CHECKPOINT, // validate scripts after the last checkpoint
CS_ALWAYS // always validate scripts
};
/** The basic transaction that is broadcasted on the network and contained in
* blocks. A transaction can contain multiple inputs and outputs.
*/
class CTransaction
{
public:
static const int CURRENT_VERSION=1;
int nVersion;
std::vector<CTxIn> vin;
std::vector<CTxOut> vout;
unsigned int nLockTime;
// Denial-of-service detection:
mutable int nDoS;
bool DoS(int nDoSIn, bool fIn) const { nDoS += nDoSIn; return fIn; }
CTransaction()
{
SetNull();
}
IMPLEMENT_SERIALIZE
(
READWRITE(this->nVersion);
nVersion = this->nVersion;
READWRITE(vin);
READWRITE(vout);
READWRITE(nLockTime);
)
void SetNull()
{
nVersion = CTransaction::CURRENT_VERSION;
vin.clear();
vout.clear();
nLockTime = 0;
nDoS = 0; // Denial-of-service prevention
}
bool IsNull() const
{
return (vin.empty() && vout.empty());
}
uint256 GetHash() const
{
return SerializeHash(*this);
}
bool IsFinal(int nBlockHeight=0, int64 nBlockTime=0) const
{
// Time based nLockTime implemented in 0.1.6
if (nLockTime == 0)
return true;
if (nBlockHeight == 0)
nBlockHeight = nBestHeight;
if (nBlockTime == 0)
nBlockTime = GetAdjustedTime();
if ((int64)nLockTime < ((int64)nLockTime < LOCKTIME_THRESHOLD ? (int64)nBlockHeight : nBlockTime))
return true;
BOOST_FOREACH(const CTxIn& txin, vin)
if (!txin.IsFinal())
return false;
return true;
}
bool IsNewerThan(const CTransaction& old) const
{
if (vin.size() != old.vin.size())
return false;
for (unsigned int i = 0; i < vin.size(); i++)
if (vin[i].prevout != old.vin[i].prevout)
return false;
bool fNewer = false;
unsigned int nLowest = std::numeric_limits<unsigned int>::max();
for (unsigned int i = 0; i < vin.size(); i++)
{
if (vin[i].nSequence != old.vin[i].nSequence)
{
if (vin[i].nSequence <= nLowest)
{
fNewer = false;
nLowest = vin[i].nSequence;
}
if (old.vin[i].nSequence < nLowest)
{
fNewer = true;
nLowest = old.vin[i].nSequence;
}
}
}
return fNewer;
}
bool IsCoinBase() const
{
return (vin.size() == 1 && vin[0].prevout.IsNull());
}
/** Check for standard transaction types
@return True if all outputs (scriptPubKeys) use only standard transaction forms
*/
bool IsStandard() const;
/** 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
@see CTransaction::FetchInputs
*/
bool AreInputsStandard(CCoinsViewCache& mapInputs) const;
/** 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;
/** 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(CCoinsViewCache& mapInputs) const;
/** Amount of bitcoins spent by this transaction.
@return sum of all outputs (note: does not include fees)
*/
int64 GetValueOut() const
{
int64 nValueOut = 0;
BOOST_FOREACH(const CTxOut& txout, vout)
{
nValueOut += txout.nValue;
if (!MoneyRange(txout.nValue) || !MoneyRange(nValueOut))
throw std::runtime_error("CTransaction::GetValueOut() : value out of range");
}
return nValueOut;
}
/** Amount of bitcoins coming in to this 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] mapInputs Map of previous transactions that have outputs we're spending
@return Sum of value of all inputs (scriptSigs)
@see CTransaction::FetchInputs
*/
int64 GetValueIn(CCoinsViewCache& mapInputs) const;
static bool AllowFree(double dPriority)
{
// Large (in bytes) low-priority (new, small-coin) transactions
// need a fee.
return dPriority > COIN * 144 / 250;
}
int64 GetMinFee(unsigned int nBlockSize=1, bool fAllowFree=true, enum GetMinFee_mode mode=GMF_BLOCK) const;
friend bool operator==(const CTransaction& a, const CTransaction& b)
{
return (a.nVersion == b.nVersion &&
a.vin == b.vin &&
a.vout == b.vout &&
a.nLockTime == b.nLockTime);
}
friend bool operator!=(const CTransaction& a, const CTransaction& b)
{
return !(a == b);
}
std::string ToString() const
{
std::string str;
str += strprintf("CTransaction(hash=%s, ver=%d, vin.size=%"PRIszu", vout.size=%"PRIszu", nLockTime=%u)\n",
GetHash().ToString().substr(0,10).c_str(),
nVersion,
vin.size(),
vout.size(),
nLockTime);
for (unsigned int i = 0; i < vin.size(); i++)
str += " " + vin[i].ToString() + "\n";
for (unsigned int i = 0; i < vout.size(); i++)
str += " " + vout[i].ToString() + "\n";
return str;
}
void print() const
{
printf("%s", ToString().c_str());
}
// Do all possible client-mode checks
bool ClientCheckInputs() const;
// Check whether all prevouts of this transaction are present in the UTXO set represented by view
bool HaveInputs(CCoinsViewCache &view) const;
// Check whether all inputs of this transaction are valid (no double spends, scripts & sigs, amounts)
// This does not modify the UTXO set
bool CheckInputs(CCoinsViewCache &view, enum CheckSig_mode csmode, unsigned int flags = SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC) const;
// Apply the effects of this transaction on the UTXO set represented by view
bool UpdateCoins(CCoinsViewCache &view, CTxUndo &txundo, int nHeight, const uint256 &txhash) const;
// Context-independent validity checks
bool CheckTransaction() const;
// Try to accept this transaction into the memory pool
bool AcceptToMemoryPool(bool fCheckInputs=true, bool* pfMissingInputs=NULL);
protected:
static const CTxOut &GetOutputFor(const CTxIn& input, CCoinsViewCache& mapInputs);
};
/** wrapper for CTxOut that provides a more compact serialization */
class CTxOutCompressor
{
private:
CTxOut &txout;
public:
static uint64 CompressAmount(uint64 nAmount);
static uint64 DecompressAmount(uint64 nAmount);
CTxOutCompressor(CTxOut &txoutIn) : txout(txoutIn) { }
IMPLEMENT_SERIALIZE(({
if (!fRead) {
uint64 nVal = CompressAmount(txout.nValue);
READWRITE(VARINT(nVal));
} else {
uint64 nVal = 0;
READWRITE(VARINT(nVal));
txout.nValue = DecompressAmount(nVal);
}
CScriptCompressor cscript(REF(txout.scriptPubKey));
READWRITE(cscript);
});)
};
/** Undo information for a CTxIn
*
* Contains the prevout's CTxOut being spent, and if this was the
* last output of the affected transaction, its metadata as well
* (coinbase or not, height, transaction version)
*/
class CTxInUndo
{
public:
CTxOut txout; // the txout data before being spent
bool fCoinBase; // if the outpoint was the last unspent: whether it belonged to a coinbase
unsigned int nHeight; // if the outpoint was the last unspent: its height
int nVersion; // if the outpoint was the last unspent: its version
CTxInUndo() : txout(), fCoinBase(false), nHeight(0), nVersion(0) {}
CTxInUndo(const CTxOut &txoutIn, bool fCoinBaseIn = false, unsigned int nHeightIn = 0, int nVersionIn = 0) : txout(txoutIn), fCoinBase(fCoinBaseIn), nHeight(nHeightIn), nVersion(nVersionIn) { }
unsigned int GetSerializeSize(int nType, int nVersion) const {
return ::GetSerializeSize(VARINT(nHeight*2+(fCoinBase ? 1 : 0)), nType, nVersion) +
(nHeight > 0 ? ::GetSerializeSize(VARINT(this->nVersion), nType, nVersion) : 0) +
::GetSerializeSize(CTxOutCompressor(REF(txout)), nType, nVersion);
}
template<typename Stream>
void Serialize(Stream &s, int nType, int nVersion) const {
::Serialize(s, VARINT(nHeight*2+(fCoinBase ? 1 : 0)), nType, nVersion);
if (nHeight > 0)
::Serialize(s, VARINT(this->nVersion), nType, nVersion);
::Serialize(s, CTxOutCompressor(REF(txout)), nType, nVersion);
}
template<typename Stream>
void Unserialize(Stream &s, int nType, int nVersion) {
unsigned int nCode = 0;
::Unserialize(s, VARINT(nCode), nType, nVersion);
nHeight = nCode / 2;
fCoinBase = nCode & 1;
if (nHeight > 0)
::Unserialize(s, VARINT(this->nVersion), nType, nVersion);
::Unserialize(s, REF(CTxOutCompressor(REF(txout))), nType, nVersion);
}
};
/** Undo information for a CTransaction */
class CTxUndo
{
public:
// undo information for all txins
std::vector<CTxInUndo> vprevout;
IMPLEMENT_SERIALIZE(
READWRITE(vprevout);
)
};
/** 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)
{
// 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(pchMessageStart) << nSize;
// Write undo data
long fileOutPos = ftell(fileout);
if (fileOutPos < 0)
return error("CBlockUndo::WriteToDisk() : ftell failed");
pos.nPos = (unsigned int)fileOutPos;
fileout << *this;
// Flush stdio buffers and commit to disk before returning
fflush(fileout);
if (!IsInitialBlockDownload())
FileCommit(fileout);
return true;
}
};
/** pruned version of CTransaction: only retains metadata and unspent transaction outputs
*
* Serialized format:
* - VARINT(nVersion)
* - VARINT(nCode)
* - unspentness bitvector, for vout[2] and further; least significant byte first
* - the non-spent CTxOuts (via CTxOutCompressor)
* - VARINT(nHeight)
*
* The nCode value consists of:
* - bit 1: IsCoinBase()
* - bit 2: vout[0] is not spent
* - bit 4: vout[1] is not spent
* - The higher bits encode N, the number of non-zero bytes in the following bitvector.
* - In case both bit 2 and bit 4 are unset, they encode N-1, as there must be at
* least one non-spent output).
*
* Example: 0104835800816115944e077fe7c803cfa57f29b36bf87c1d358bb85e
* <><><--------------------------------------------><---->
* | \ | /
* version code vout[1] height
*
* - version = 1
* - code = 4 (vout[1] is not spent, and 0 non-zero bytes of bitvector follow)
* - unspentness bitvector: as 0 non-zero bytes follow, it has length 0
* - vout[1]: 835800816115944e077fe7c803cfa57f29b36bf87c1d35
* * 8358: compact amount representation for 60000000000 (600 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 816115944e077fe7c803cfa57f29b36bf87c1d35: address uint160
* - height = 203998
*
*
* Example: 0109044086ef97d5790061b01caab50f1b8e9c50a5057eb43c2d9563a4eebbd123008c988f1a4a4de2161e0f50aac7f17e7f9555caa486af3b
* <><><--><--------------------------------------------------><----------------------------------------------><---->
* / \ \ | | /
* version code unspentness vout[4] vout[16] height
*
* - version = 1
* - code = 9 (coinbase, neither vout[0] or vout[1] are unspent,
* 2 (1, +1 because both bit 2 and bit 4 are unset) non-zero bitvector bytes follow)
* - unspentness bitvector: bits 2 (0x04) and 14 (0x4000) are set, so vout[2+2] and vout[14+2] are unspent
* - vout[4]: 86ef97d5790061b01caab50f1b8e9c50a5057eb43c2d9563a4ee
* * 86ef97d579: compact amount representation for 234925952 (2.35 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 61b01caab50f1b8e9c50a5057eb43c2d9563a4ee: address uint160
* - vout[16]: bbd123008c988f1a4a4de2161e0f50aac7f17e7f9555caa4
* * bbd123: compact amount representation for 110397 (0.001 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 8c988f1a4a4de2161e0f50aac7f17e7f9555caa4: address uint160
* - height = 120891
*/
class CCoins
{
public:
// whether transaction is a coinbase
bool fCoinBase;
// unspent transaction outputs; spent outputs are .IsNull(); spent outputs at the end of the array are dropped
std::vector<CTxOut> vout;
// at which height this transaction was included in the active block chain
int nHeight;
// version of the CTransaction; accesses to this value should probably check for nHeight as well,
// as new tx version will probably only be introduced at certain heights
int nVersion;
// construct a CCoins from a CTransaction, at a given height
CCoins(const CTransaction &tx, int nHeightIn) : fCoinBase(tx.IsCoinBase()), vout(tx.vout), nHeight(nHeightIn), nVersion(tx.nVersion) { }
// empty constructor
CCoins() : fCoinBase(false), vout(0), nHeight(0), nVersion(0) { }
// remove spent outputs at the end of vout
void Cleanup() {
while (vout.size() > 0 && vout.back().IsNull())
vout.pop_back();
}
// equality test
friend bool operator==(const CCoins &a, const CCoins &b) {
return a.fCoinBase == b.fCoinBase &&
a.nHeight == b.nHeight &&
a.nVersion == b.nVersion &&
a.vout == b.vout;
}
friend bool operator!=(const CCoins &a, const CCoins &b) {
return !(a == b);
}
// calculate number of bytes for the bitmask, and its number of non-zero bytes
// each bit in the bitmask represents the availability of one output, but the
// availabilities of the first two outputs are encoded separately
void CalcMaskSize(unsigned int &nBytes, unsigned int &nNonzeroBytes) const {
unsigned int nLastUsedByte = 0;
for (unsigned int b = 0; 2+b*8 < vout.size(); b++) {
bool fZero = true;
for (unsigned int i = 0; i < 8 && 2+b*8+i < vout.size(); i++) {
if (!vout[2+b*8+i].IsNull()) {
fZero = false;
continue;
}
}
if (!fZero) {
nLastUsedByte = b + 1;
nNonzeroBytes++;
}
}
nBytes += nLastUsedByte;
}
bool IsCoinBase() const {
return fCoinBase;
}
unsigned int GetSerializeSize(int nType, int nVersion) const {
unsigned int nSize = 0;
unsigned int nMaskSize = 0, nMaskCode = 0;
CalcMaskSize(nMaskSize, nMaskCode);
bool fFirst = vout.size() > 0 && !vout[0].IsNull();
bool fSecond = vout.size() > 1 && !vout[1].IsNull();
assert(fFirst || fSecond || nMaskCode);
unsigned int nCode = 8*(nMaskCode - (fFirst || fSecond ? 0 : 1)) + (fCoinBase ? 1 : 0) + (fFirst ? 2 : 0) + (fSecond ? 4 : 0);
// version
nSize += ::GetSerializeSize(VARINT(this->nVersion), nType, nVersion);
// size of header code
nSize += ::GetSerializeSize(VARINT(nCode), nType, nVersion);
// spentness bitmask
nSize += nMaskSize;
// txouts themself
for (unsigned int i = 0; i < vout.size(); i++)
if (!vout[i].IsNull())
nSize += ::GetSerializeSize(CTxOutCompressor(REF(vout[i])), nType, nVersion);
// height
nSize += ::GetSerializeSize(VARINT(nHeight), nType, nVersion);
return nSize;
}
template<typename Stream>
void Serialize(Stream &s, int nType, int nVersion) const {
unsigned int nMaskSize = 0, nMaskCode = 0;
CalcMaskSize(nMaskSize, nMaskCode);
bool fFirst = vout.size() > 0 && !vout[0].IsNull();
bool fSecond = vout.size() > 1 && !vout[1].IsNull();
assert(fFirst || fSecond || nMaskCode);
unsigned int nCode = 8*(nMaskCode - (fFirst || fSecond ? 0 : 1)) + (fCoinBase ? 1 : 0) + (fFirst ? 2 : 0) + (fSecond ? 4 : 0);
// version
::Serialize(s, VARINT(this->nVersion), nType, nVersion);
// header code
::Serialize(s, VARINT(nCode), nType, nVersion);
// spentness bitmask
for (unsigned int b = 0; b<nMaskSize; b++) {
unsigned char chAvail = 0;
for (unsigned int i = 0; i < 8 && 2+b*8+i < vout.size(); i++)
if (!vout[2+b*8+i].IsNull())
chAvail |= (1 << i);
::Serialize(s, chAvail, nType, nVersion);
}
// txouts themself
for (unsigned int i = 0; i < vout.size(); i++) {
if (!vout[i].IsNull())
::Serialize(s, CTxOutCompressor(REF(vout[i])), nType, nVersion);
}
// coinbase height
::Serialize(s, VARINT(nHeight), nType, nVersion);
}
template<typename Stream>
void Unserialize(Stream &s, int nType, int nVersion) {
unsigned int nCode = 0;
// version
::Unserialize(s, VARINT(this->nVersion), nType, nVersion);
// header code
::Unserialize(s, VARINT(nCode), nType, nVersion);
fCoinBase = nCode & 1;
std::vector<bool> vAvail(2, false);
vAvail[0] = nCode & 2;
vAvail[1] = nCode & 4;
unsigned int nMaskCode = (nCode / 8) + ((nCode & 6) != 0 ? 0 : 1);
// spentness bitmask
while (nMaskCode > 0) {
unsigned char chAvail = 0;
::Unserialize(s, chAvail, nType, nVersion);
for (unsigned int p = 0; p < 8; p++) {
bool f = (chAvail & (1 << p)) != 0;
vAvail.push_back(f);
}
if (chAvail != 0)
nMaskCode--;
}
// txouts themself
vout.assign(vAvail.size(), CTxOut());
for (unsigned int i = 0; i < vAvail.size(); i++) {
if (vAvail[i])
::Unserialize(s, REF(CTxOutCompressor(vout[i])), nType, nVersion);
}
// coinbase height
::Unserialize(s, VARINT(nHeight), nType, nVersion);
Cleanup();
}
// mark an outpoint spent, and construct undo information
bool Spend(const COutPoint &out, CTxInUndo &undo) {
if (out.n >= vout.size())
return false;
if (vout[out.n].IsNull())
return false;
undo = CTxInUndo(vout[out.n]);
vout[out.n].SetNull();
Cleanup();
if (vout.size() == 0) {
undo.nHeight = nHeight;
undo.fCoinBase = fCoinBase;
undo.nVersion = this->nVersion;
}
return true;
}
// mark a vout spent
bool Spend(int nPos) {
CTxInUndo undo;
COutPoint out(0, nPos);
return Spend(out, undo);
}
// check whether a particular output is still available
bool IsAvailable(unsigned int nPos) const {
return (nPos < vout.size() && !vout[nPos].IsNull());
}
// check whether the entire CCoins is spent
// note that only !IsPruned() CCoins can be serialized
bool IsPruned() const {
BOOST_FOREACH(const CTxOut &out, vout)
if (!out.IsNull())
return false;
return true;
}
};
/** 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 fCheckInputs=true);
};
/** Nodes collect new transactions into a block, hash them into a hash tree,
* and scan through nonce values to make the block's hash satisfy proof-of-work
* requirements. When they solve the proof-of-work, they broadcast the block
* to everyone and the block is added to the block chain. The first transaction
* in the block is a special one that creates a new coin owned by the creator
* of the block.
*/
class CBlockHeader
{
public:
// header
static const int CURRENT_VERSION=2;
int nVersion;
uint256 hashPrevBlock;
uint256 hashMerkleRoot;
unsigned int nTime;
unsigned int nBits;
unsigned int nNonce;
CBlockHeader()
{
SetNull();
}
IMPLEMENT_SERIALIZE
(
READWRITE(this->nVersion);
nVersion = this->nVersion;
READWRITE(hashPrevBlock);
READWRITE(hashMerkleRoot);
READWRITE(nTime);
READWRITE(nBits);
READWRITE(nNonce);
)
void SetNull()
{
nVersion = CBlockHeader::CURRENT_VERSION;
hashPrevBlock = 0;
hashMerkleRoot = 0;
nTime = 0;
nBits = 0;
nNonce = 0;
}
bool IsNull() const
{
return (nBits == 0);
}
uint256 GetHash() const
{
return Hash(BEGIN(nVersion), END(nNonce));
}
int64 GetBlockTime() const
{
return (int64)nTime;
}
void UpdateTime(const CBlockIndex* pindexPrev);
};
class CBlock : public CBlockHeader
{
public:
// network and disk
std::vector<CTransaction> vtx;
// memory only
mutable std::vector<uint256> vMerkleTree;
// Denial-of-service detection:
mutable int nDoS;
bool DoS(int nDoSIn, bool fIn) const { nDoS += nDoSIn; return fIn; }
CBlock()
{
SetNull();
}
CBlock(const CBlockHeader &header)
{
SetNull();
*((CBlockHeader*)this) = header;
}
IMPLEMENT_SERIALIZE
(
READWRITE(*(CBlockHeader*)this);
READWRITE(vtx);
)
void SetNull()
{
CBlockHeader::SetNull();
vtx.clear();
vMerkleTree.clear();
nDoS = 0;
}
uint256 BuildMerkleTree() const
{
vMerkleTree.clear();
BOOST_FOREACH(const CTransaction& tx, vtx)
vMerkleTree.push_back(tx.GetHash());
int j = 0;
for (int nSize = vtx.size(); nSize > 1; nSize = (nSize + 1) / 2)
{
for (int i = 0; i < nSize; i += 2)
{
int i2 = std::min(i+1, nSize-1);
vMerkleTree.push_back(Hash(BEGIN(vMerkleTree[j+i]), END(vMerkleTree[j+i]),
BEGIN(vMerkleTree[j+i2]), END(vMerkleTree[j+i2])));
}
j += nSize;
}
return (vMerkleTree.empty() ? 0 : vMerkleTree.back());
}
const uint256 &GetTxHash(unsigned int nIndex) const {
assert(vMerkleTree.size() > 0); // BuildMerkleTree must have been called first
assert(nIndex < vtx.size());
return vMerkleTree[nIndex];
}
std::vector<uint256> GetMerkleBranch(int nIndex) const
{
if (vMerkleTree.empty())
BuildMerkleTree();
std::vector<uint256> vMerkleBranch;
int j = 0;
for (int nSize = vtx.size(); nSize > 1; nSize = (nSize + 1) / 2)
{
int i = std::min(nIndex^1, nSize-1);
vMerkleBranch.push_back(vMerkleTree[j+i]);
nIndex >>= 1;
j += nSize;
}
return vMerkleBranch;
}
static uint256 CheckMerkleBranch(uint256 hash, const std::vector<uint256>& vMerkleBranch, int nIndex)
{
if (nIndex == -1)
return 0;
BOOST_FOREACH(const uint256& otherside, vMerkleBranch)
{
if (nIndex & 1)
hash = Hash(BEGIN(otherside), END(otherside), BEGIN(hash), END(hash));
else
hash = Hash(BEGIN(hash), END(hash), BEGIN(otherside), END(otherside));
nIndex >>= 1;
}
return hash;
}
bool WriteToDisk(CDiskBlockPos &pos)
{
// Open history file to append
CAutoFile fileout = CAutoFile(OpenBlockFile(pos), SER_DISK, CLIENT_VERSION);
if (!fileout)
return error("CBlock::WriteToDisk() : OpenBlockFile failed");
// Write index header
unsigned int nSize = fileout.GetSerializeSize(*this);
fileout << FLATDATA(pchMessageStart) << nSize;
// Write block
long fileOutPos = ftell(fileout);
if (fileOutPos < 0)
return error("CBlock::WriteToDisk() : ftell failed");
pos.nPos = (unsigned int)fileOutPos;
fileout << *this;
// Flush stdio buffers and commit to disk before returning
fflush(fileout);
if (!IsInitialBlockDownload())
FileCommit(fileout);
return true;
}
bool ReadFromDisk(const CDiskBlockPos &pos)
{
SetNull();
// Open history file to read
CAutoFile filein = CAutoFile(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
if (!filein)
return error("CBlock::ReadFromDisk() : OpenBlockFile failed");
// Read block
try {
filein >> *this;
}
catch (std::exception &e) {
return error("%s() : deserialize or I/O error", __PRETTY_FUNCTION__);
}
// Check the header
if (!CheckProofOfWork(GetHash(), nBits))
return error("CBlock::ReadFromDisk() : errors in block header");
return true;
}
void print() const
{
printf("CBlock(hash=%s, ver=%d, hashPrevBlock=%s, hashMerkleRoot=%s, nTime=%u, nBits=%08x, nNonce=%u, vtx=%"PRIszu")\n",
BlockHashStr(GetHash()).c_str(),
nVersion,
BlockHashStr(hashPrevBlock).c_str(),
hashMerkleRoot.ToString().substr(0,10).c_str(),
nTime, nBits, nNonce,
vtx.size());
for (unsigned int i = 0; i < vtx.size(); i++)
{
printf(" ");
vtx[i].print();
}
printf(" vMerkleTree: ");
for (unsigned int i = 0; i < vMerkleTree.size(); i++)
printf("%s ", vMerkleTree[i].ToString().substr(0,10).c_str());
printf("\n");
}
// Undo the effects of this block (with given index) on the UTXO set represented by coins
bool DisconnectBlock(CBlockIndex *pindex, CCoinsViewCache &coins);
// Apply the effects of this block (with given index) on the UTXO set represented by coins
bool ConnectBlock(CBlockIndex *pindex, CCoinsViewCache &coins, bool fJustCheck=false);
// Read a block from disk
bool ReadFromDisk(const CBlockIndex* pindex);
// Add this block to the block index, and if necessary, switch the active block chain to this
bool AddToBlockIndex(const CDiskBlockPos &pos);
// Context-independent validity checks
bool CheckBlock(bool fCheckPOW=true, bool fCheckMerkleRoot=true) const;
// Store block on disk
// if dbp is provided, the file is known to already reside on disk
bool AcceptBlock(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. pprev and pnext link a path through the
* main/longest chain. A blockindex may have multiple pprev pointing back
* to it, but pnext will only point forward to the longest branch, or will
* be null if the block is not part of the longest chain.
*/
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;
// (memory only) pointer to the index of the *active* successor of this block
CBlockIndex* pnext;
// 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
CBigNum bnChainWork;
// 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;
pnext = NULL;
nHeight = 0;
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
bnChainWork = 0;
nTx = 0;
nChainTx = 0;
nStatus = 0;
nVersion = 0;
hashMerkleRoot = 0;
nTime = 0;
nBits = 0;
nNonce = 0;
}
CBlockIndex(CBlockHeader& block)
{
phashBlock = NULL;
pprev = NULL;
pnext = NULL;
nHeight = 0;
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
bnChainWork = 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;
} else
ret.SetNull();
return ret;
}
CDiskBlockPos GetUndoPos() const {
CDiskBlockPos ret;
if (nStatus & BLOCK_HAVE_UNDO) {
ret.nFile = nFile;
ret.nPos = nUndoPos;
} else
ret.SetNull();
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 (pnext || this == pindexBest);
}
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->pnext)
return GetBlockTime();
pindex = pindex->pnext;
}
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, pnext, nHeight,
hashMerkleRoot.ToString().substr(0,10).c_str(),
BlockHashStr(GetBlockHash()).c_str());
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
struct CBlockIndexWorkComparator
{
bool operator()(CBlockIndex *pa, CBlockIndex *pb) {
if (pa->bnChainWork > pb->bnChainWork) return false;
if (pa->bnChainWork < pb->bnChainWork) 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(),
BlockHashStr(hashPrev).c_str());
return str;
}
void print() const
{
printf("%s\n", ToString().c_str());
}
};
/** 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)
{
std::map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hashBlock);
if (mi != mapBlockIndex.end())
Set((*mi).second);
}
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();
}
void Set(const CBlockIndex* pindex)
{
vHave.clear();
int nStep = 1;
while (pindex)
{
vHave.push_back(pindex->GetBlockHash());
// Exponentially larger steps back
for (int i = 0; pindex && i < nStep; i++)
pindex = pindex->pprev;
if (vHave.size() > 10)
nStep *= 2;
}
vHave.push_back(hashGenesisBlock);
}
int GetDistanceBack()
{
// Retrace how far back it was in the sender's branch
int nDistance = 0;
int nStep = 1;
BOOST_FOREACH(const uint256& hash, vHave)
{
std::map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hash);
if (mi != mapBlockIndex.end())
{
CBlockIndex* pindex = (*mi).second;
if (pindex->IsInMainChain())
return nDistance;
}
nDistance += nStep;
if (nDistance > 10)
nStep *= 2;
}
return nDistance;
}
CBlockIndex* GetBlockIndex()
{
// Find the first block the caller has in the main chain
BOOST_FOREACH(const uint256& hash, vHave)
{
std::map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hash);
if (mi != mapBlockIndex.end())
{
CBlockIndex* pindex = (*mi).second;
if (pindex->IsInMainChain())
return pindex;
}
}
return pindexGenesisBlock;
}
uint256 GetBlockHash()
{
// Find the first block the caller has in the main chain
BOOST_FOREACH(const uint256& hash, vHave)
{
std::map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hash);
if (mi != mapBlockIndex.end())
{
CBlockIndex* pindex = (*mi).second;
if (pindex->IsInMainChain())
return hash;
}
}
return hashGenesisBlock;
}
int GetHeight()
{
CBlockIndex* pindex = GetBlockIndex();
if (!pindex)
return 0;
return pindex->nHeight;
}
};
class CTxMemPool
{
public:
mutable CCriticalSection cs;
std::map<uint256, CTransaction> mapTx;
std::map<COutPoint, CInPoint> mapNextTx;
bool accept(CTransaction &tx, bool fCheckInputs, bool* pfMissingInputs);
bool addUnchecked(const uint256& hash, CTransaction &tx);
bool remove(CTransaction &tx);
void clear();
void queryHashes(std::vector<uint256>& vtxid);
void pruneSpent(const uint256& hash, CCoins &coins);
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;
uint64 nTransactions;
uint64 nTransactionOutputs;
uint64 nSerializedSize;
CCoinsStats() : nHeight(0), nTransactions(0), nTransactionOutputs(0), nSerializedSize(0) {}
};
/** Abstract view on the open txout dataset. */
class CCoinsView
{
public:
// Retrieve the CCoins (unspent transaction outputs) for a given txid
virtual bool GetCoins(uint256 txid, CCoins &coins);
// Modify the CCoins for a given txid
virtual bool SetCoins(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(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(uint256 txid, CCoins &coins);
bool SetCoins(uint256 txid, const CCoins &coins);
bool HaveCoins(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(uint256 txid, CCoins &coins);
bool SetCoins(uint256 txid, const CCoins &coins);
bool HaveCoins(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(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();
private:
std::map<uint256,CCoins>::iterator FetchCoins(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(uint256 txid, CCoins &coins);
bool HaveCoins(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;
#endif