Add Sidechain half of Drivechains & BMM (#2)

* Add updated SCDB, remove subsidy, add GUI elements

* Remove old SCDB files

* Remove unused script operator

* Update sidechain database

* Update validation and miner

* Update sidechain page

* Update sidechain client

* Remove unused

* Pushing some initial work on BMM

- Removed PoW files
- Added BMM files
- Added BMM based chain activation code
- Modified block header for BMM
- h* validation

* Update sidechain client

- Added validate critical hash (h*) call

* Remove unused PoW related rpc calls

* Add BMM tab to sidechain page

* BMM update

src/Makefile.am

@@ -81,6 +81,7 @@ BITCOIN_CORE_H = \
   base58.h \
   bloom.h \
   blockencodings.h \
+  bmm.h \
   chain.h \
   chainparams.h \
   chainparamsbase.h \
@@ -118,7 +119,6 @@ BITCOIN_CORE_H = \
   policy/fees.h \
   policy/policy.h \
   policy/rbf.h \
-  pow.h \
   protocol.h \
   random.h \
   reverselock.h \
@@ -137,6 +137,7 @@ BITCOIN_CORE_H = \
   support/cleanse.h \
   support/events.h \
   support/lockedpool.h \
+  sidechainclient.h \
   sync.h \
   threadsafety.h \
   threadinterrupt.h \
@@ -179,6 +180,7 @@ libbitcoin_server_a_SOURCES = \
   addrdb.cpp \
   bloom.cpp \
   blockencodings.cpp \
+  bmm.cpp \
   chain.cpp \
   checkpoints.cpp \
   httprpc.cpp \
@@ -192,7 +194,6 @@ libbitcoin_server_a_SOURCES = \
   noui.cpp \
   policy/fees.cpp \
   policy/policy.cpp \
-  pow.cpp \
   rest.cpp \
   rpc/blockchain.cpp \
   rpc/mining.cpp \
@@ -202,6 +203,7 @@ libbitcoin_server_a_SOURCES = \
   rpc/server.cpp \
   script/sigcache.cpp \
   script/ismine.cpp \
+  sidechainclient.cpp \
   timedata.cpp \
   torcontrol.cpp \
   txdb.cpp \
@@ -272,6 +274,8 @@ libbitcoin_consensus_a_SOURCES = \
   prevector.h \
   primitives/block.cpp \
   primitives/block.h \
+  primitives/sidechain.cpp \
+  primitives/sidechain.h \
   primitives/transaction.cpp \
   primitives/transaction.h \
   pubkey.cpp \

src/Makefile.qt.include

@@ -110,6 +110,7 @@ QT_FORMS_UI = \
   qt/forms/debugwindow.ui \
   qt/forms/sendcoinsdialog.ui \
   qt/forms/sendcoinsentry.ui \
+  qt/forms/sidechainpage.ui \
   qt/forms/signverifymessagedialog.ui \
   qt/forms/transactiondescdialog.ui
 
@@ -147,6 +148,8 @@ QT_MOC_CPP = \
   qt/moc_rpcconsole.cpp \
   qt/moc_sendcoinsdialog.cpp \
   qt/moc_sendcoinsentry.cpp \
+  qt/moc_sidechainhistorytablemodel.cpp \
+  qt/moc_sidechainpage.cpp \
   qt/moc_signverifymessagedialog.cpp \
   qt/moc_splashscreen.cpp \
   qt/moc_trafficgraphwidget.cpp \
@@ -218,6 +221,8 @@ BITCOIN_QT_H = \
   qt/rpcconsole.h \
   qt/sendcoinsdialog.h \
   qt/sendcoinsentry.h \
+  qt/sidechainhistorytablemodel.h \
+  qt/sidechainpage.h \
   qt/signverifymessagedialog.h \
   qt/splashscreen.h \
   qt/trafficgraphwidget.h \
@@ -333,6 +338,8 @@ BITCOIN_QT_WALLET_CPP = \
   qt/recentrequeststablemodel.cpp \
   qt/sendcoinsdialog.cpp \
   qt/sendcoinsentry.cpp \
+  qt/sidechainhistorytablemodel.cpp \
+  qt/sidechainpage.cpp \
   qt/signverifymessagedialog.cpp \
   qt/transactiondesc.cpp \
   qt/transactiondescdialog.cpp \
@@ -353,7 +360,7 @@ if ENABLE_WALLET
 BITCOIN_QT_CPP += $(BITCOIN_QT_WALLET_CPP)
 endif
 
-RES_IMAGES = 
+RES_IMAGES =
 
 RES_MOVIES = $(wildcard $(srcdir)/qt/res/movies/spinner-*.png)
 

src/bmm.cpp

@@ -0,0 +1,34 @@
+#include "bmm.h"
+
+#include "primitives/block.h"
+
+BMM::BMM()
+{
+
+}
+
+bool BMM::StoreBMMBlock(const CBlock& block)
+{
+    if (!block.vtx.size())
+        return false;
+
+    uint256 hashBlock = block.GetHash();
+
+    // Already have block stored
+    if (mapBMMBlocks.find(hashBlock) != mapBMMBlocks.end())
+        return false;
+
+    mapBMMBlocks[hashBlock] = block;
+
+    return true;
+}
+
+bool BMM::GetBMMBlock(const uint256& hashBlock, CBlock& block)
+{
+    if (mapBMMBlocks.find(hashBlock) == mapBMMBlocks.end())
+        return false;
+
+    block = mapBMMBlocks[hashBlock];
+
+    return true;
+}

src/bmm.h

@@ -0,0 +1,23 @@
+#ifndef BITCOIN_BMM_H
+#define BITCOIN_BMM_H
+
+#include "uint256.h"
+
+#include <map>
+
+class CBlock;
+
+class BMM
+{
+public:
+    BMM();
+
+    bool StoreBMMBlock(const CBlock& block);
+
+    bool GetBMMBlock(const uint256& hashBlock, CBlock& block);
+
+private:
+    std::map<uint256, CBlock> mapBMMBlocks;
+};
+
+#endif // BITCOIN_BMM_H

src/chain.cpp

@@ -116,35 +116,3 @@ void CBlockIndex::BuildSkip()
     if (pprev)
         pskip = pprev->GetAncestor(GetSkipHeight(nHeight));
 }
-
-arith_uint256 GetBlockProof(const CBlockIndex& block)
-{
-    arith_uint256 bnTarget;
-    bool fNegative;
-    bool fOverflow;
-    bnTarget.SetCompact(block.nBits, &fNegative, &fOverflow);
-    if (fNegative || fOverflow || bnTarget == 0)
-        return 0;
-    // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256
-    // as it's too large for a arith_uint256. However, as 2**256 is at least as large
-    // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1,
-    // or ~bnTarget / (nTarget+1) + 1.
-    return (~bnTarget / (bnTarget + 1)) + 1;
-}
-
-int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params& params)
-{
-    arith_uint256 r;
-    int sign = 1;
-    if (to.nChainWork > from.nChainWork) {
-        r = to.nChainWork - from.nChainWork;
-    } else {
-        r = from.nChainWork - to.nChainWork;
-        sign = -1;
-    }
-    r = r * arith_uint256(params.nPowTargetSpacing) / GetBlockProof(tip);
-    if (r.bits() > 63) {
-        return sign * std::numeric_limits<int64_t>::max();
-    }
-    return sign * r.GetLow64();
-}

src/chain.h

@@ -8,7 +8,6 @@
 
 #include "arith_uint256.h"
 #include "primitives/block.h"
-#include "pow.h"
 #include "tinyformat.h"
 #include "uint256.h"
 
@@ -177,9 +176,6 @@ class CBlockIndex
     //! 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
-    arith_uint256 nChainWork;
-
     //! Number of transactions in this block.
     //! Note: in a potential headers-first mode, this number cannot be relied upon
     unsigned int nTx;
@@ -196,8 +192,9 @@ class CBlockIndex
     int nVersion;
     uint256 hashMerkleRoot;
     unsigned int nTime;
-    unsigned int nBits;
     unsigned int nNonce;
+    std::string criticalProof;
+    CMutableTransaction txCritical;
 
     //! (memory only) Sequential id assigned to distinguish order in which blocks are received.
     int32_t nSequenceId;
@@ -214,18 +211,19 @@ class CBlockIndex
         nFile = 0;
         nDataPos = 0;
         nUndoPos = 0;
-        nChainWork = arith_uint256();
         nTx = 0;
         nChainTx = 0;
         nStatus = 0;
         nSequenceId = 0;
         nTimeMax = 0;
 
-        nVersion       = 0;
-        hashMerkleRoot = uint256();
-        nTime          = 0;
-        nBits          = 0;
-        nNonce         = 0;
+        nVersion            = 0;
+        hashMerkleRoot      = uint256();
+        nTime               = 0;
+        nNonce              = 0;
+
+        criticalProof   = "";
+        txCritical  = CMutableTransaction();
     }
 
     CBlockIndex()
@@ -237,11 +235,12 @@ class CBlockIndex
     {
         SetNull();
 
-        nVersion       = block.nVersion;
-        hashMerkleRoot = block.hashMerkleRoot;
-        nTime          = block.nTime;
-        nBits          = block.nBits;
-        nNonce         = block.nNonce;
+        nVersion            = block.nVersion;
+        hashMerkleRoot      = block.hashMerkleRoot;
+        nTime               = block.nTime;
+        nNonce              = block.nNonce;
+        criticalProof   = block.criticalProof;
+        txCritical  = block.txCritical;
     }
 
     CDiskBlockPos GetBlockPos() const {
@@ -270,8 +269,9 @@ class CBlockIndex
             block.hashPrevBlock = pprev->GetBlockHash();
         block.hashMerkleRoot = hashMerkleRoot;
         block.nTime          = nTime;
-        block.nBits          = nBits;
         block.nNonce         = nNonce;
+        block.criticalProof  = criticalProof;
+        block.txCritical     = txCritical;
         return block;
     }
 
@@ -345,10 +345,6 @@ class CBlockIndex
     const CBlockIndex* GetAncestor(int height) const;
 };
 
-arith_uint256 GetBlockProof(const CBlockIndex& block);
-/** Return the time it would take to redo the work difference between from and to, assuming the current hashrate corresponds to the difficulty at tip, in seconds. */
-int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params&);
-
 /** Used to marshal pointers into hashes for db storage. */
 class CDiskBlockIndex : public CBlockIndex
 {
@@ -386,8 +382,9 @@ class CDiskBlockIndex : public CBlockIndex
         READWRITE(hashPrev);
         READWRITE(hashMerkleRoot);
         READWRITE(nTime);
-        READWRITE(nBits);
         READWRITE(nNonce);
+        READWRITE(criticalProof);
+        READWRITE(txCritical);
     }
 
     uint256 GetBlockHash() const
@@ -397,12 +394,12 @@ class CDiskBlockIndex : public CBlockIndex
         block.hashPrevBlock   = hashPrev;
         block.hashMerkleRoot  = hashMerkleRoot;
         block.nTime           = nTime;
-        block.nBits           = nBits;
         block.nNonce          = nNonce;
+        block.criticalProof   = criticalProof;
+        block.txCritical      = txCritical;
         return block.GetHash();
     }
 
-
     std::string ToString() const
     {
         std::string str = "CDiskBlockIndex(";