+ Mining by matching address segment to block hash (on tansactions greater than 500 coins), 50% of the block subsidy.
+
+ Increased security on Proof-of-Work blocks though verification of coinbase tx value, size, and destinations of coinbase transactions via Proof-Of-Transaction checking.
+ // Since the minimum signed integer cannot be represented as positive so long as its type is signed, and it's not well-defined what happens if you make it unsigned before negating it, we instead increment the negative integer by 1, convert it, then increment the (now positive) unsigned integer by 1 to compensate
+ n = -(sn + 1);
+ ++n;
+ fNegative = true;
+ } else {
+ n = sn;
+ fNegative = false;
+ }
+
+ bool fLeadingZeroes = true;
+ for (int i = 0; i < 8; i++)
+ {
+ unsigned char c = (n >> 56) & 0xff;
+ n <<= 8;
+ if (fLeadingZeroes)
+ {
+ if (c == 0)
+ continue;
+ if (c & 0x80)
+ *p++ = (fNegative ? 0x80 : 0);
+ else if (fNegative)
+ c |= 0x80;
+ fLeadingZeroes = false;
+ }
+ *p++ = c;
+ }
+ unsigned int nSize = p - (pch + 4);
+ pch[0] = (nSize >> 24) & 0xff;
+ pch[1] = (nSize >> 16) & 0xff;
+ pch[2] = (nSize >> 8) & 0xff;
+ pch[3] = (nSize) & 0xff;
+ BN_mpi2bn(pch, p - pch, this);
+ }
+
+ uint64 getuint64()
+ {
+ unsigned int nSize = BN_bn2mpi(this, NULL);
+ if (nSize < 4)
+ return 0;
+ std::vector<unsigned char> vch(nSize);
+ BN_bn2mpi(this, &vch[0]);
+ if (vch.size() > 4)
+ vch[4] &= 0x7f;
+ uint64 n = 0;
+ for (unsigned int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--)
+ ((unsigned char*)&n)[i] = vch[j];
+ return n;
+ }
+
+ void setuint64(uint64 n)
+ {
+ unsigned char pch[sizeof(n) + 6];
+ unsigned char* p = pch + 4;
+ bool fLeadingZeroes = true;
+ for (int i = 0; i < 8; i++)
+ {
+ unsigned char c = (n >> 56) & 0xff;
+ n <<= 8;
+ if (fLeadingZeroes)
+ {
+ if (c == 0)
+ continue;
+ if (c & 0x80)
+ *p++ = 0;
+ fLeadingZeroes = false;
+ }
+ *p++ = c;
+ }
+ unsigned int nSize = p - (pch + 4);
+ pch[0] = (nSize >> 24) & 0xff;
+ pch[1] = (nSize >> 16) & 0xff;
+ pch[2] = (nSize >> 8) & 0xff;
+ pch[3] = (nSize) & 0xff;
+ BN_mpi2bn(pch, p - pch, this);
+ }
+
+ void setuint256(uint256 n)
+ {
+ unsigned char pch[sizeof(n) + 6];
+ unsigned char* p = pch + 4;
+ bool fLeadingZeroes = true;
+ unsigned char* pbegin = (unsigned char*)&n;
+ unsigned char* psrc = pbegin + sizeof(n);
+ while (psrc != pbegin)
+ {
+ unsigned char c = *(--psrc);
+ if (fLeadingZeroes)
+ {
+ if (c == 0)
+ continue;
+ if (c & 0x80)
+ *p++ = 0;
+ fLeadingZeroes = false;
+ }
+ *p++ = c;
+ }
+ unsigned int nSize = p - (pch + 4);
+ pch[0] = (nSize >> 24) & 0xff;
+ pch[1] = (nSize >> 16) & 0xff;
+ pch[2] = (nSize >> 8) & 0xff;
+ pch[3] = (nSize >> 0) & 0xff;
+ BN_mpi2bn(pch, p - pch, this);
+ }
+
+ uint256 getuint256() const
+ {
+ unsigned int nSize = BN_bn2mpi(this, NULL);
+ if (nSize < 4)
+ return 0;
+ std::vector<unsigned char> vch(nSize);
+ BN_bn2mpi(this, &vch[0]);
+ if (vch.size() > 4)
+ vch[4] &= 0x7f;
+ uint256 n = 0;
+ for (unsigned int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--)
+ if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
+ {
+ CBlockIndex* pindex = pindexSyncCheckpoint;
+ while (pindex->nHeight > pindexCheckpointRecv->nHeight)
+ if (!(pindex = pindex->pprev))
+ return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
+ if (pindex->GetBlockHash() != hashCheckpoint)
+ {
+ hashInvalidCheckpoint = hashCheckpoint;
+ return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
+ }
+ return false; // ignore older checkpoint
+ }
+
+ CBlockIndex* pindex = pindexCheckpointRecv;
+ while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
+ if (!(pindex = pindex->pprev))
+ return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
+ if (pindex->GetBlockHash() != hashSyncCheckpoint)
+ {
+ hashInvalidCheckpoint = hashCheckpoint;
+ return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
+ return error("CheckProofOfStake() : called on non-coinstake %s", tx.GetHash().ToString().c_str());
+
+ const CTxIn& txin = tx.vin[0];
+ CTxDB txdb("r");
+ CTransaction txPrev;
+ CTxIndex txindex;
+ if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
+ return tx.DoS(1, error("CheckProofOfStake() : INFO: read txPrev failed")); // previous transaction not in main chain, may occur during initial download
+ return tx.DoS(1, error("CheckProofOfStake() : INFO: check kernel failed on coinstake %s, hashProof=%s", tx.GetHash().ToString().c_str(), hashProofOfStake.ToString().c_str())); // may occur during initial download or if behind on block chain sync
+Install the [Windows Software Development Kit version 7.1](http://www.microsoft.com/downloads/dlx/en-us/listdetailsview.aspx?FamilyID=6b6c21d2-2006-4afa-9702-529fa782d63b).
+
+Download and extract the [Snappy source distribution](http://snappy.googlecode.com/files/snappy-1.0.5.tar.gz)
+
+1. Open the "Windows SDK 7.1 Command Prompt" :
+ Start Menu -> "Microsoft Windows SDK v7.1" > "Windows SDK 7.1 Command Prompt"