use CBlockIndex* insted of uint256 for UpdatedBlockTip signal

- removes mapBlockIndex find operation
- theoretically allows removing the cs_main lock during zqm notification while introducing a new file position lock

src/main.cpp

@@ -2707,7 +2707,7 @@ bool ActivateBestChain(CValidationState &state, CBlock *pblock) {
                         pnode->PushInventory(CInv(MSG_BLOCK, hashNewTip));
             }
             // Notify external listeners about the new tip.
-            GetMainSignals().UpdatedBlockTip(hashNewTip);
+            GetMainSignals().UpdatedBlockTip(pindexNewTip);
             uiInterface.NotifyBlockTip(hashNewTip);
         }
     } while(pindexMostWork != chainActive.Tip());

src/validationinterface.h

@@ -31,7 +31,7 @@ void SyncWithWallets(const CTransaction& tx, const CBlock* pblock = NULL);
 
 class CValidationInterface {
 protected:
-    virtual void UpdatedBlockTip(const uint256 &newHashTip) {}
+    virtual void UpdatedBlockTip(const CBlockIndex *pindex) {}
     virtual void SyncTransaction(const CTransaction &tx, const CBlock *pblock) {}
     virtual void EraseFromWallet(const uint256 &hash) {}
     virtual void ChainTip(const CBlockIndex *pindex, const CBlock *pblock, ZCIncrementalMerkleTree tree, bool added) {}
@@ -47,7 +47,7 @@ protected:
 
 struct CMainSignals {
     /** Notifies listeners of updated block chain tip */
-    boost::signals2::signal<void (const uint256 &)> UpdatedBlockTip;
+    boost::signals2::signal<void (const CBlockIndex *)> UpdatedBlockTip;
     /** Notifies listeners of updated transaction data (transaction, and optionally the block it is found in. */
     boost::signals2::signal<void (const CTransaction &, const CBlock *)> SyncTransaction;
     /** Notifies listeners of an erased transaction (currently disabled, requires transaction replacement). */

src/zmq/zmqabstractnotifier.cpp

@@ -11,7 +11,7 @@ CZMQAbstractNotifier::~CZMQAbstractNotifier()
     assert(!psocket);
 }
 
-bool CZMQAbstractNotifier::NotifyBlock(const uint256 &/*hash*/)
+bool CZMQAbstractNotifier::NotifyBlock(const CBlockIndex * /*CBlockIndex*/)
 {
     return true;
 }

src/zmq/zmqabstractnotifier.h

@@ -7,7 +7,9 @@
 
 #include "zmqconfig.h"
 
+class CBlockIndex;
 class CZMQAbstractNotifier;
+
 typedef CZMQAbstractNotifier* (*CZMQNotifierFactory)();
 
 class CZMQAbstractNotifier
@@ -30,7 +32,7 @@ public:
     virtual bool Initialize(void *pcontext) = 0;
     virtual void Shutdown() = 0;
 
-    virtual bool NotifyBlock(const uint256 &hash);
+    virtual bool NotifyBlock(const CBlockIndex *pindex);
     virtual bool NotifyTransaction(const CTransaction &transaction);
 
 protected:

src/zmq/zmqnotificationinterface.cpp

@@ -125,12 +125,12 @@ void CZMQNotificationInterface::Shutdown()
     }
 }
 
-void CZMQNotificationInterface::UpdatedBlockTip(const uint256 &hash)
+void CZMQNotificationInterface::UpdatedBlockTip(const CBlockIndex *pindex)
 {
     for (std::list<CZMQAbstractNotifier*>::iterator i = notifiers.begin(); i!=notifiers.end(); )
     {
         CZMQAbstractNotifier *notifier = *i;
-        if (notifier->NotifyBlock(hash))
+        if (notifier->NotifyBlock(pindex))
         {
             i++;
         }

src/zmq/zmqnotificationinterface.h

@@ -9,6 +9,7 @@
 #include <string>
 #include <map>
 
+class CBlockIndex;
 class CZMQAbstractNotifier;
 
 class CZMQNotificationInterface : public CValidationInterface
@@ -24,7 +25,7 @@ protected:
 
     // CValidationInterface
     void SyncTransaction(const CTransaction &tx, const CBlock *pblock);
-    void UpdatedBlockTip(const uint256 &newHashTip);
+    void UpdatedBlockTip(const CBlockIndex *pindex);
 
 private:
     CZMQNotificationInterface();

src/zmq/zmqpublishnotifier.cpp

@@ -116,8 +116,9 @@ void CZMQAbstractPublishNotifier::Shutdown()
     psocket = 0;
 }
 
-bool CZMQPublishHashBlockNotifier::NotifyBlock(const uint256 &hash)
+bool CZMQPublishHashBlockNotifier::NotifyBlock(const CBlockIndex *pindex)
 {
+    uint256 hash = pindex->GetBlockHash();
     LogPrint("zmq", "Publish hash block %s\n", hash.GetHex());
     char data[32];
     for (unsigned int i = 0; i < 32; i++)
@@ -137,18 +138,15 @@ bool CZMQPublishHashTransactionNotifier::NotifyTransaction(const CTransaction &t
     return rc == 0;
 }
 
-bool CZMQPublishRawBlockNotifier::NotifyBlock(const uint256 &hash)
+bool CZMQPublishRawBlockNotifier::NotifyBlock(const CBlockIndex *pindex)
 {
-    LogPrint("zmq", "Publish raw block %s\n", hash.GetHex());
+    LogPrint("zmq", "Publish raw block %s\n", pindex->GetBlockHash().GetHex());
 
     CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
     {
         LOCK(cs_main);
-
         CBlock block;
-        CBlockIndex* pblockindex = mapBlockIndex[hash];
-
-        if(!ReadBlockFromDisk(block, pblockindex))
+        if(!ReadBlockFromDisk(block, pindex))
         {
             zmqError("Can't read block from disk");
             return false;

src/zmq/zmqpublishnotifier.h

@@ -7,6 +7,8 @@
 
 #include "zmqabstractnotifier.h"
 
+class CBlockIndex;
+
 class CZMQAbstractPublishNotifier : public CZMQAbstractNotifier
 {
 public:
@@ -17,7 +19,7 @@ public:
 class CZMQPublishHashBlockNotifier : public CZMQAbstractPublishNotifier
 {
 public:
-    bool NotifyBlock(const uint256 &hash);
+    bool NotifyBlock(const CBlockIndex *pindex);
 };
 
 class CZMQPublishHashTransactionNotifier : public CZMQAbstractPublishNotifier
@@ -29,7 +31,7 @@ public:
 class CZMQPublishRawBlockNotifier : public CZMQAbstractPublishNotifier
 {
 public:
-    bool NotifyBlock(const uint256 &hash);
+    bool NotifyBlock(const CBlockIndex *pindex);
 };
 
 class CZMQPublishRawTransactionNotifier : public CZMQAbstractPublishNotifier