Prepare database format for multi-stage block processing

This commit adds a status field and a transaction counter to the block
indexes.

1 files changed, 97 insertions, 16 deletions

diff --git a/src/main.h b/src/main.h
index 1150ca4c02..687171ef7c 100644
--- a/src/main.h
+++ b/src/main.h
@@ -23,6 +23,8 @@ class CInv;
 class CRequestTracker;
 class CNode;
 
+class CBlockIndexWorkComparator;
+
 static const unsigned int MAX_BLOCK_SIZE = 1000000;
 static const unsigned int MAX_BLOCK_SIZE_GEN = MAX_BLOCK_SIZE/2;
 static const unsigned int MAX_BLOCK_SIGOPS = MAX_BLOCK_SIZE/50;
@@ -55,6 +57,7 @@ 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;
@@ -114,6 +117,9 @@ int GetNumBlocksOfPeers();
 bool IsInitialBlockDownload();
 std::string GetWarnings(std::string strFor);
 bool GetTransaction(const uint256 &hash, CTransaction &tx, uint256 &hashBlock, bool fAllowSlow = false);
+bool SetBestChain(CBlockIndex* pindexNew);
+bool ConnectBestBlock();
+
 
 
 
@@ -1234,9 +1240,6 @@ public:
     // Read a block from disk
     bool ReadFromDisk(const CBlockIndex* pindex, bool fReadTransactions=true);
 
-    // Make this block (with given index) the new tip of the active block chain
-    bool SetBestChain(CBlockIndex* pindexNew);
-
     // Add this block to the block index, and if necessary, switch the active block chain to this
     bool AddToBlockIndex(const CDiskBlockPos &pos);
 
@@ -1308,6 +1311,24 @@ 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
@@ -1318,14 +1339,40 @@ extern int nLastBlockFile;
 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;
-    CDiskBlockPos pos;
+
+    // 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;
@@ -1340,9 +1387,13 @@ public:
         pprev = NULL;
         pnext = NULL;
         nHeight = 0;
-        pos.SetNull();
+        nFile = 0;
+        nDataPos = 0;
         nUndoPos = 0;
         bnChainWork = 0;
+        nTx = 0;
+        nChainTx = 0;
+        nStatus = 0;
 
         nVersion       = 0;
         hashMerkleRoot = 0;
@@ -1357,9 +1408,13 @@ public:
         pprev = NULL;
         pnext = NULL;
         nHeight = 0;
-        pos.SetNull();
+        nFile = 0;
+        nDataPos = 0;
         nUndoPos = 0;
         bnChainWork = 0;
+        nTx = 0;
+        nChainTx = 0;
+        nStatus = 0;
 
         nVersion       = block.nVersion;
         hashMerkleRoot = block.hashMerkleRoot;
@@ -1369,15 +1424,22 @@ public:
     }
 
     CDiskBlockPos GetBlockPos() const {
-        return pos;
+        CDiskBlockPos ret;
+        if (nStatus & BLOCK_HAVE_DATA) {
+            ret.nFile = nFile;
+            ret.nPos  = nDataPos;
+        } else
+            ret.SetNull();
+        return ret;
     }
 
     CDiskBlockPos GetUndoPos() const {
-        CDiskBlockPos ret = pos;
-        if (nUndoPos == 0)
+        CDiskBlockPos ret;
+        if (nStatus & BLOCK_HAVE_UNDO) {
+            ret.nFile = nFile;
+            ret.nPos  = nUndoPos;
+        } else
             ret.SetNull();
-        else
-            ret.nPos = nUndoPos - 1;
         return ret;
     }
 
@@ -1472,6 +1534,19 @@ public:
     }
 };
 
+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. */
@@ -1491,11 +1566,17 @@ public:
     IMPLEMENT_SERIALIZE
     (
         if (!(nType & SER_GETHASH))
-            READWRITE(nVersion);
-
-        READWRITE(nHeight);
-        READWRITE(pos);
-        READWRITE(nUndoPos);
+            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);