diff options
Diffstat (limited to 'src/core.h')
| -rw-r--r-- | src/core.h | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/src/core.h b/src/core.h index 21ca6618a2..c86e1f499d 100644 --- a/src/core.h +++ b/src/core.h @@ -340,4 +340,336 @@ public: } }; +/** 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); + ) +}; + + +/** 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(); + if (vout.empty()) + std::vector<CTxOut>().swap(vout); + } + + void swap(CCoins &to) { + std::swap(to.fCoinBase, fCoinBase); + to.vout.swap(vout); + std::swap(to.nHeight, nHeight); + std::swap(to.nVersion, nVersion); + } + + // 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; + } +}; + + #endif |