X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=src%2Fkernel.h;h=eca9744516ed8060935aa5a4ccf7ba472065f1dd;hb=f2bcacaf01a0c77083fdf9d1baa6a201078c1efd;hp=dc2fbb0710fe2f727940adfad0d15a9e433c550d;hpb=d8f8063eda45b8dec864b28bb98839a2dd3a8170;p=novacoin.git

diff --git a/src/kernel.h b/src/kernel.h
index dc2fbb0..eca9744 100644
--- a/src/kernel.h
+++ b/src/kernel.h
@@ -5,6 +5,12 @@
 #define PPCOIN_KERNEL_H
 
 #include "main.h"
+#include "wallet.h"
+
+using namespace std;
+
+// ChainDB upgrade time
+extern unsigned int nModifierUpgradeTime;
 
 // MODIFIER_INTERVAL: time to elapse before new modifier is computed
 extern unsigned int nModifierInterval;
@@ -13,27 +19,48 @@ extern unsigned int nModifierInterval;
 // ratio of group interval length between the last group and the first group
 static const int MODIFIER_INTERVAL_RATIO = 3;
 
+// Whether the given block is subject to new modifier protocol
+bool IsFixedModifierInterval(unsigned int nTimeBlock);
+
 // Compute the hash modifier for proof-of-stake
-bool ComputeNextStakeModifier(const CBlockIndex* pindexPrev, uint64& nStakeModifier, bool& fGeneratedStakeModifier);
+bool ComputeNextStakeModifier(const CBlockIndex* pindexCurrent, uint64_t& nStakeModifier, bool& fGeneratedStakeModifier);
+
+// The stake modifier used to hash for a stake kernel is chosen as the stake
+// modifier about a selection interval later than the coin generating the kernel
+bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier);
 
 // Check whether stake kernel meets hash target
 // Sets hashProofOfStake on success return
-bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, unsigned int nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, unsigned int nTimeTx, uint256& hashProofOfStake, uint256& targetProofOfStake, bool fPrintProofOfStake=false);
+bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, uint32_t nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, uint32_t nTimeTx, uint256& hashProofOfStake, uint256& targetProofOfStake, bool fPrintProofOfStake=false);
+
+// Precompute hashing state for static part of kernel
+void GetKernelMidstate(uint64_t nStakeModifier, uint32_t nBlockTime, uint32_t nTxOffset, uint32_t nInputTxTime, uint32_t nOut, SHA256_CTX &ctx);
+
+// Scan given midstate for kernel solutions
+bool ScanMidstateForward(SHA256_CTX &ctx, uint32_t nBits, uint32_t nInputTxTime, int64_t nValueIn, std::pair<uint32_t, uint32_t> &SearchInterval, std::pair<uint256, uint32_t> &solution);
+bool ScanMidstateBackward(SHA256_CTX &ctx, uint32_t nBits, uint32_t nInputTxTime, int64_t nValueIn, std::pair<uint32_t, uint32_t> &SearchInterval, std::pair<uint256, uint32_t> &solution);
 
 // Check kernel hash target and coinstake signature
 // Sets hashProofOfStake on success return
 bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake, uint256& targetProofOfStake);
 
-// Check whether the coinstake timestamp meets protocol
-bool CheckCoinStakeTimestamp(int64 nTimeBlock, int64 nTimeTx);
-
 // Get stake modifier checksum
-unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex);
+uint32_t GetStakeModifierChecksum(const CBlockIndex* pindex);
 
 // Check stake modifier hard checkpoints
-bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierChecksum);
+bool CheckStakeModifierCheckpoints(int nHeight, uint32_t nStakeModifierChecksum);
 
 // Get time weight using supplied timestamps
-int64 GetWeight(int64 nIntervalBeginning, int64 nIntervalEnd);
+inline int64_t GetWeight(int64_t nIntervalBeginning, int64_t nIntervalEnd)
+{
+    // Kernel hash weight starts from 0 at the 30-day min age
+    // this change increases active coins participating the hash and helps
+    // to secure the network when proof-of-stake difficulty is low
+    //
+    // Maximum TimeWeight is 90 days.
+
+    return min(nIntervalEnd - nIntervalBeginning - nStakeMinAge, (int64_t)nStakeMaxAge);
+}
+
 
 #endif // PPCOIN_KERNEL_H