WIP: namespace/key

src/coins.cpp

@@ -10,6 +10,8 @@
 bool CCoinsView::GetCoin(const COutPoint &outpoint, Coin &coin) const { return false; }
 uint256 CCoinsView::GetBestBlock() const { return uint256(); }
 std::vector<uint256> CCoinsView::GetHeadBlocks() const { return std::vector<uint256>(); }
+bool CCoinsView::GetName(const valtype &nameSpace, const valtype &key, CKevaData &data) const { return false; }
+bool CCoinsView::GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const { return false; }
 bool CCoinsView::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) { return false; }
 CCoinsViewCursor *CCoinsView::Cursor() const { return nullptr; }
 
@@ -24,6 +26,8 @@ bool CCoinsViewBacked::GetCoin(const COutPoint &outpoint, Coin &coin) const { re
 bool CCoinsViewBacked::HaveCoin(const COutPoint &outpoint) const { return base->HaveCoin(outpoint); }
 uint256 CCoinsViewBacked::GetBestBlock() const { return base->GetBestBlock(); }
 std::vector<uint256> CCoinsViewBacked::GetHeadBlocks() const { return base->GetHeadBlocks(); }
+bool CCoinsViewBacked::GetName(const valtype &nameSpace, const valtype &key, CKevaData &data) const { return false; }
+bool CCoinsViewBacked::GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const { return false; }
 void CCoinsViewBacked::SetBackend(CCoinsView &viewIn) { base = &viewIn; }
 bool CCoinsViewBacked::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) { return base->BatchWrite(mapCoins, hashBlock); }
 CCoinsViewCursor *CCoinsViewBacked::Cursor() const { return base->Cursor(); }
@@ -142,6 +146,96 @@ void CCoinsViewCache::SetBestBlock(const uint256 &hashBlockIn) {
     hashBlock = hashBlockIn;
 }
 
+bool CCoinsViewCache::GetName(const valtype &nameSpace, const valtype &key, CKevaData &data) const {
+    if (cacheNames.isDeleted(nameSpace, key))
+        return false;
+    if (cacheNames.get(nameSpace, key, data))
+        return true;
+
+    /* Note: This does not attempt to cache name queries.  The cache
+       only keeps track of changes!  */
+
+    return base->GetName(nameSpace, key, data);
+}
+
+
+bool CCoinsViewCache::GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const {
+    /* Query the base view first, and then apply the cached changes (if
+       there are any).  */
+
+    if (!base->GetNamesForHeight(nHeight, names))
+        return false;
+
+    cacheNames.updateNamesForHeight(nHeight, names);
+    return true;
+}
+
+/* undo is set if the change is due to disconnecting blocks / going back in
+   time.  The ordinary case (!undo) means that we update the name normally,
+   going forward in time.  This is important for keeping track of the
+   name history.  */
+void CCoinsViewCache::SetName(const valtype &nameSpace, const valtype &key, const CKevaData& data, bool undo) {
+    CKevaData oldData;
+    if (GetName(nameSpace, key, oldData))
+    {
+#if 0
+        cacheNames.removeExpireIndex(name, oldData.getHeight());
+
+        /* Update the name history.  If we are undoing, we expect that
+           the top history item matches the data being set now.  If we
+           are not undoing, push the overwritten data onto the history stack.
+           Note that we only have to do this if the name already existed
+           in the database.  Otherwise, no special action is required
+           for the name history.  */
+        if (fNameHistory)
+        {
+            CNameHistory history;
+            if (!GetNameHistory(name, history))
+            {
+                /* Ensure that the history stack is indeed (still) empty
+                   and was not modified by the failing GetNameHistory call.  */
+                assert(history.empty());
+            }
+
+            if (undo)
+                history.pop(data);
+            else
+                history.push(oldData);
+
+            cacheNames.setHistory(name, history);
+        }
+#endif
+    } else
+        assert (!undo);
+
+    cacheNames.set(nameSpace, key, data);
+#if 0
+    cacheNames.addExpireIndex(name, data.getHeight());
+#endif
+}
+
+void CCoinsViewCache::DeleteName(const valtype &nameSpace, const valtype &key) {
+    CKevaData oldData;
+    if (GetName(nameSpace, key, oldData)) {
+#if 0        
+        cacheNames.removeExpireIndex(name, oldData.getHeight());
+#endif
+    }
+    else
+        assert(false);
+
+#if 0
+    if (fNameHistory)
+    {
+        /* When deleting a name, the history should already be clean.  */
+        CNameHistory history;
+        assert (!GetNameHistory(name, history) || history.empty());
+    }
+#endif
+
+    cacheNames.remove(nameSpace, key);
+}
+
 bool CCoinsViewCache::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlockIn) {
     for (CCoinsMap::iterator it = mapCoins.begin(); it != mapCoins.end(); it = mapCoins.erase(it)) {
         // Ignore non-dirty entries (optimization).

src/coins.h

@@ -11,6 +11,7 @@
 #include <core_memusage.h>
 #include <hash.h>
 #include <memusage.h>
+#include <keva/common.h>
 #include <serialize.h>
 #include <uint256.h>
 
@@ -163,6 +164,12 @@ public:
     //! the old block hash, in that order.
     virtual std::vector<uint256> GetHeadBlocks() const;
 
+    // Get a name (if it exists)
+    virtual bool GetName(const valtype& nameSpace, const valtype& key, CKevaData& data) const;    
+
+    // Query for names that were updated at the given height
+    virtual bool GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const;
+
     //! Do a bulk modification (multiple Coin changes + BestBlock change).
     //! The passed mapCoins can be modified.
     virtual bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
@@ -190,6 +197,8 @@ public:
     bool HaveCoin(const COutPoint &outpoint) const override;
     uint256 GetBestBlock() const override;
     std::vector<uint256> GetHeadBlocks() const override;
+    bool GetName(const valtype& nameSpace, const valtype& key, CKevaData& data) const override;
+    bool GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const override;
     void SetBackend(CCoinsView &viewIn);
     bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override;
     CCoinsViewCursor *Cursor() const override;
@@ -211,6 +220,9 @@ protected:
     /* Cached dynamic memory usage for the inner Coin objects. */
     mutable size_t cachedCoinsUsage;
 
+    /** Name changes cache.  */
+    CKevaCache cacheNames;
+
 public:
     CCoinsViewCache(CCoinsView *baseIn);
 
@@ -224,11 +236,17 @@ public:
     bool HaveCoin(const COutPoint &outpoint) const override;
     uint256 GetBestBlock() const override;
     void SetBestBlock(const uint256 &hashBlock);
+    bool GetName(const valtype &nameSpace, const valtype &key, CKevaData &data) const override;
+    bool GetNamesForHeight(unsigned nHeight, std::set<valtype>& names) const override;
     bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override;
     CCoinsViewCursor* Cursor() const override {
         throw std::logic_error("CCoinsViewCache cursor iteration not supported.");
     }
 
+    /* Changes to the name database.  */
+    void SetName(const valtype &nameSpace, const valtype &key, const CKevaData &data, bool undo);
+    void DeleteName(const valtype &nameSpace, const valtype &key);
+
     /**
      * Check if we have the given utxo already loaded in this cache.
      * The semantics are the same as HaveCoin(), but no calls to

src/keva/common.cpp

@@ -38,7 +38,7 @@ CNameIterator::~CNameIterator ()
 }
 
 /* ************************************************************************** */
-/* CNameCacheNameIterator.  */
+/* CKevaCacheNameIterator.  */
 
 class CCacheNameIterator : public CNameIterator
 {
@@ -46,7 +46,7 @@ class CCacheNameIterator : public CNameIterator
 private:
 
   /** Reference to cache object that is used.  */
-  const CNameCache& cache;
+  const CKevaCache& cache;
 
   /** Base iterator to combine with the cache.  */
   CNameIterator* base;
@@ -59,7 +59,7 @@ private:
   CKevaData baseData;
 
   /** Iterator of the cache's entries.  */
-  CNameCache::EntryMap::const_iterator cacheIter;
+  CKevaCache::EntryMap::const_iterator cacheIter;
 
   /* Call the base iterator's next() routine to fill in the internal
      "cache" for the next entry.  This already skips entries that are
@@ -73,7 +73,7 @@ public:
    * @param c The cache object to use.
    * @param b The base iterator.
    */
-  CCacheNameIterator (const CNameCache& c, CNameIterator* b);
+  CCacheNameIterator (const CKevaCache& c, CNameIterator* b);
 
   /* Destruct, this deletes also the base iterator.  */
   ~CCacheNameIterator ();
@@ -84,7 +84,7 @@ public:
 
 };
 
-CCacheNameIterator::CCacheNameIterator (const CNameCache& c, CNameIterator* b)
+CCacheNameIterator::CCacheNameIterator (const CKevaCache& c, CNameIterator* b)
   : cache(c), base(b)
 {
   /* Add a seek-to-start to ensure that everything is consistent.  This call
@@ -147,7 +147,7 @@ CCacheNameIterator::next (valtype& name, CKevaData& data)
         {
           assert (baseName != cacheIter->first);
 
-          CNameCache::NameComparator cmp;
+          CKevaCache::NameComparator cmp;
           useBase = cmp (baseName, cacheIter->first);
         }
     }
@@ -170,11 +170,12 @@ CCacheNameIterator::next (valtype& name, CKevaData& data)
 }
 
 /* ************************************************************************** */
-/* CNameCache.  */
+/* CKevaCache.  */
 
 bool
-CNameCache::get (const valtype& name, CKevaData& data) const
+CKevaCache::get (const valtype& nameSpace, const valtype& key, CKevaData& data) const
 {
+  valtype name = nameSpace + key;
   const EntryMap::const_iterator i = entries.find (name);
   if (i == entries.end ())
     return false;
@@ -184,8 +185,9 @@ CNameCache::get (const valtype& name, CKevaData& data) const
 }
 
 void
-CNameCache::set (const valtype& name, const CKevaData& data)
+CKevaCache::set (const valtype& nameSpace, const valtype& key, const CKevaData& data)
 {
+  valtype name = nameSpace + key;
   const std::set<valtype>::iterator di = deleted.find (name);
   if (di != deleted.end ())
     deleted.erase (di);
@@ -198,8 +200,9 @@ CNameCache::set (const valtype& name, const CKevaData& data)
 }
 
 void
-CNameCache::remove (const valtype& name)
+CKevaCache::remove (const valtype& nameSpace, const valtype& key)
 {
+  valtype name = nameSpace + key;
   const EntryMap::iterator ei = entries.find (name);
   if (ei != entries.end ())
     entries.erase (ei);
@@ -208,13 +211,14 @@ CNameCache::remove (const valtype& name)
 }
 
 CNameIterator*
-CNameCache::iterateNames (CNameIterator* base) const
+CKevaCache::iterateNames (CNameIterator* base) const
 {
   return new CCacheNameIterator (*this, base);
 }
 
+#if 0
 bool
-CNameCache::getHistory (const valtype& name, CNameHistory& res) const
+CKevaCache::getHistory (const valtype& name, CNameHistory& res) const
 {
   assert (fNameHistory);
 
@@ -227,7 +231,7 @@ CNameCache::getHistory (const valtype& name, CNameHistory& res) const
 }
 
 void
-CNameCache::setHistory (const valtype& name, const CNameHistory& data)
+CKevaCache::setHistory (const valtype& name, const CNameHistory& data)
 {
   assert (fNameHistory);
 
@@ -237,9 +241,10 @@ CNameCache::setHistory (const valtype& name, const CNameHistory& data)
   else
     history.insert (std::make_pair (name, data));
 }
+#endif
 
 void
-CNameCache::updateNamesForHeight (unsigned nHeight,
+CKevaCache::updateNamesForHeight (unsigned nHeight,
                                   std::set<valtype>& names) const
 {
   /* Seek in the map of cached entries to the first one corresponding
@@ -263,21 +268,21 @@ CNameCache::updateNamesForHeight (unsigned nHeight,
 }
 
 void
-CNameCache::addExpireIndex (const valtype& name, unsigned height)
+CKevaCache::addExpireIndex (const valtype& name, unsigned height)
 {
   const ExpireEntry entry(height, name);
   expireIndex[entry] = true;
 }
 
 void
-CNameCache::removeExpireIndex (const valtype& name, unsigned height)
+CKevaCache::removeExpireIndex (const valtype& name, unsigned height)
 {
   const ExpireEntry entry(height, name);
   expireIndex[entry] = false;
 }
 
 void
-CNameCache::apply (const CNameCache& cache)
+CKevaCache::apply (const CKevaCache& cache)
 {
   for (EntryMap::const_iterator i = cache.entries.begin ();
        i != cache.entries.end (); ++i)

src/keva/common.h

@@ -274,7 +274,7 @@ public:
  * new names (or updates to them), this also keeps track of deleted names
  * (when rolling back changes).
  */
-class CNameCache
+class CKevaCache
 {
 
 private:
@@ -306,6 +306,7 @@ public:
    * the height is serialised as byte-array with little-endian order,
    * which does not correspond to the ordering by actual value.
    */
+#if 0
   class ExpireEntry
   {
   public:
@@ -369,6 +370,7 @@ public:
     }
 
   };
+#endif
 
   /**
    * Type of name entry map.  This is public because it is also used
@@ -383,17 +385,21 @@ private:
   /** Deleted names.  */
   std::set<valtype> deleted;
 
+#if 0
   /**
    * New or updated history stacks.  If they are empty, the corresponding
    * database entry is deleted instead.
    */
   std::map<valtype, CNameHistory> history;
+#endif
 
+#if 0
   /**
    * Changes to be performed to the expire index.  The entry is mapped
    * to either "true" (meaning to add it) or "false" (delete).
    */
   std::map<ExpireEntry, bool> expireIndex;
+#endif
 
   friend class CCacheNameIterator;
 
@@ -404,8 +410,10 @@ public:
   {
     entries.clear ();
     deleted.clear ();
+#if 0
     history.clear ();
     expireIndex.clear ();
+#endif
   }
 
   /**
@@ -417,38 +425,40 @@ public:
   inline bool
   empty () const
   {
-    if (entries.empty () && deleted.empty ())
-      {
-        assert (history.empty () && expireIndex.empty ());
-        return true;
-      }
+    if (entries.empty () && deleted.empty ()) {
+#if 0
+      assert (history.empty () && expireIndex.empty ());
+#endif
+      return true;
+    }
 
     return false;
   }
 
   /* See if the given name is marked as deleted.  */
   inline bool
-  isDeleted (const valtype& name) const
+  isDeleted (const valtype& nameSpace, const valtype& key) const
   {
     return (deleted.count (name) > 0); 
   }
 
   /* Try to get a name's associated data.  This looks only
      in entries, and doesn't care about deleted data.  */
-  bool get (const valtype& name, CKevaData& data) const;
+  bool get (const valtype& nameSpace, const valtype& key, CKevaData& data) const;
 
   /* Insert (or update) a name.  If it is marked as "deleted", this also
      removes the "deleted" mark.  */
-  void set (const valtype& name, const CKevaData& data);
+  void set (const valtype& nameSpace, const valtype& key, const CKevaData& data);
 
   /* Delete a name.  If it is in the "entries" set also, remove it there.  */
-  void remove (const valtype& name);
+  void remove (const valtype& nameSpace, const valtype& key);
 
   /* Return a name iterator that combines a "base" iterator with the changes
      made to it according to the cache.  The base iterator is taken
      ownership of.  */
   CNameIterator* iterateNames (CNameIterator* base) const;
 
+#if 0
   /**
    * Query for an history entry.
    * @param name The name to look up.
@@ -463,6 +473,7 @@ public:
    * @param data The new history entry.
    */
   void setHistory (const valtype& name, const CNameHistory& data);
+#endif
 
   /* Query the cached changes to the expire index.  In particular,
      for a given height and a given set of names that were indexed to
@@ -470,14 +481,16 @@ public:
      are represented by the cached expire index changes.  */
   void updateNamesForHeight (unsigned nHeight, std::set<valtype>& names) const;
 
+#if 0
   /* Add an expire-index entry.  */
   void addExpireIndex (const valtype& name, unsigned height);
 
   /* Remove an expire-index entry.  */
   void removeExpireIndex (const valtype& name, unsigned height);
+#endif
 
   /* Apply all the changes in the passed-in record on top of this one.  */
-  void apply (const CNameCache& cache);
+  void apply (const CKevaCache& cache);
 
   /* Write all cached changes to a database batch update object.  */
   void writeBatch (CDBBatch& batch) const;

src/keva/main.cpp

@@ -26,19 +26,20 @@
 /* CKevaTxUndo.  */
 
 void
-CKevaTxUndo::fromOldState(const valtype& nm, const CCoinsView& view)
+CKevaTxUndo::fromOldState(const valtype& nameSpace, const valtype& key, const CCoinsView& view)
 {
-  name = nm;
-  isNew = !view.GetName(name, oldData);
+  this->nameSpace = nameSpace;
+  this->key = key;
+  isNew = !view.GetName(nameSpace, key, oldData);
 }
 
 void
-CKevaTxUndo::apply (CCoinsViewCache& view) const
+CKevaTxUndo::apply(CCoinsViewCache& view) const
 {
   if (isNew)
-    view.DeleteName(name);
+    view.DeleteName(nameSpace, key);
   else
-    view.SetName(name, oldData, true);
+    view.SetName(nameSpace, key, oldData, true);
 }
 
 /* ************************************************************************** */
@@ -504,6 +505,7 @@ ApplyNameTransaction (const CTransaction& tx, unsigned nHeight,
 {
   assert (nHeight != MEMPOOL_HEIGHT);
 
+#if 0
   /* Handle historic bugs that should *not* be applied.  Names that are
      outputs should be marked as unspendable in this case.  Otherwise,
      we get an inconsistency between the UTXO set and the name database.  */
@@ -521,34 +523,34 @@ ApplyNameTransaction (const CTransaction& tx, unsigned nHeight,
           }
       return;
     }
+#endif
 
   /* This check must be done *after* the historic bug fixing above!  Some
      of the names that must be handled above are actually produced by
      transactions *not* marked as Namecoin tx.  */
-  if (!tx.IsNamecoin ())
+  if (!tx.IsKevacoin ())
     return;
 
   /* Changes are encoded in the outputs.  We don't have to do any checks,
      so simply apply all these.  */
 
-  for (unsigned i = 0; i < tx.vout.size (); ++i)
-    {
-      const CNameScript op(tx.vout[i].scriptPubKey);
-      if (op.isNameOp () && op.isAnyUpdate ())
-        {
-          const valtype& name = op.getOpName ();
-          LogPrint (BCLog::NAMES, "Updating name at height %d: %s\n",
-                    nHeight, ValtypeToString (name).c_str ());
-
-          CKevaTxUndo opUndo;
-          opUndo.fromOldState (name, view);
-          undo.vnameundo.push_back (opUndo);
-
-          CNameData data;
-          data.fromScript (nHeight, COutPoint (tx.GetHash (), i), op);
-          view.SetName (name, data, false);
-        }
+  for (unsigned i = 0; i < tx.vout.size (); ++i) {
+    const CKevaScript op(tx.vout[i].scriptPubKey);
+    if (op.isKevaOp () && op.isAnyUpdate ()) {
+      const valtype& nameSpace = op.getOpNamespace();
+      const valtype& key = op.getOpKey();
+      LogPrint (BCLog::KEVA, "Updating name at height %d: %s\n",
+                nHeight, ValtypeToString (nameSpace).c_str ());
+
+      CKevaTxUndo opUndo;
+      opUndo.fromOldState(nameSpace, key, view);
+      undo.vkevaundo.push_back(opUndo);
+
+      CKevaData data;
+      data.fromScript (nHeight, COutPoint (tx.GetHash (), i), op);
+      view.SetName (nameSpace, key, data, false);
     }
+  }
 }
 
 bool

src/keva/main.h

@@ -51,8 +51,11 @@ class CKevaTxUndo
 
 private:
 
-  /** The name this concerns.  */
-  valtype name;
+  /** The namespace this concerns.  */
+  valtype nameSpace;
+
+  /** The key this concerns.  */
+  valtype key;
 
   /** Whether this was an entirely new name (no update).  */
   bool isNew;
@@ -79,7 +82,7 @@ public:
    * @param nm The name that is being updated.
    * @param view The (old!) chain state.
    */
-  void fromOldState (const valtype& nm, const CCoinsView& view);
+  void fromOldState (const valtype& nameSpace, const valtype& key, const CCoinsView& view);
 
   /**
    * Apply the undo to the chain state given.

src/primitives/transaction.cpp

@@ -62,6 +62,12 @@ uint256 CMutableTransaction::GetHash() const
     return SerializeHash(*this, SER_GETHASH, SERIALIZE_TRANSACTION_NO_WITNESS);
 }
 
+void CMutableTransaction::SetKevacoin()
+{
+    assert (nVersion == CTransaction::CURRENT_VERSION);
+    nVersion = CTransaction::KEVACOIN_VERSION;
+}
+
 uint256 CTransaction::ComputeHash() const
 {
     return SerializeHash(*this, SER_GETHASH, SERIALIZE_TRANSACTION_NO_WITNESS);

src/primitives/transaction.h

@@ -266,6 +266,7 @@ class CTransaction
 public:
     // Default transaction version.
     static const int32_t CURRENT_VERSION=2;
+    static const int32_t KEVACOIN_VERSION=0x7100;
 
     // Changing the default transaction version requires a two step process: first
     // adapting relay policy by bumping MAX_STANDARD_VERSION, and then later date
@@ -335,6 +336,11 @@ public:
         return (vin.size() == 1 && vin[0].prevout.IsNull());
     }
 
+    bool IsKevacoin() const
+    {
+        return nVersion == KEVACOIN_VERSION;
+    }
+
     friend bool operator==(const CTransaction& a, const CTransaction& b)
     {
         return a.hash == b.hash;
@@ -404,6 +410,12 @@ struct CMutableTransaction
         }
         return false;
     }
+
+    /**
+     * Turn this into a Kevacoin version transaction.  It is assumed
+     * that it isn't already.
+     */
+    void SetKevacoin();
 };
 
 typedef std::shared_ptr<const CTransaction> CTransactionRef;

src/script/keva.h

@@ -52,7 +52,7 @@ public:
    * @return True iff this is a name operation.
    */
   inline bool
-  isNameOp () const
+  isKevaOp () const
   {
     switch (op) {
       case OP_KEVA_PUT:
@@ -80,10 +80,10 @@ public:
 
   /**
    * Return the name operation.  This returns OP_NAME_NEW, OP_NAME_FIRSTUPDATE
-   * or OP_NAME_UPDATE.  Do not call if this is not a name script.
+   * or OP_NAME_UPDATE.  Do not call if this is not a keva script.
    * @return The name operation opcode.
    */
-  inline opcodetype getNameOp() const
+  inline opcodetype getKevaOp() const
   {
     switch (op) {
       case OP_KEVA_PUT:      
@@ -119,9 +119,9 @@ public:
   /**
    * Return the name operation name.  This call is only valid for
    * OP_KEVA_NAMESPACE or OP_KEVA_PUT.
-   * @return The name operation's name.
+   * @return The keva operation's namespace.
    */
-  inline const valtype& getOpName () const
+  inline const valtype& getOpNamespace() const
   {
     switch (op) {
       case OP_KEVA_PUT:
@@ -140,7 +140,7 @@ public:
    * OP_KEVA_PUT.
    * @return The name operation's value.
    */
-  inline const valtype& getOpValue () const
+  inline const valtype& getOpNamespaceValue() const
   {
     switch (op) {
       case OP_KEVA_PUT:
@@ -153,15 +153,51 @@ public:
   }
 
   /**
-   * Check if the given script is a name script.  This is a utility method.
+   * Return the keva operation key.  This call is only valid for
+   * OP_KEVA_PUT.
+   * @return The keva operation's value.
+   */
+  inline const valtype& getOpKey() const
+  {
+    switch (op) {
+      case OP_KEVA_PUT:
+        return args[0];
+
+      case OP_KEVA_NAMESPACE:
+        return args[0];
+
+      default:
+        assert(false);
+    }
+  }
+
+  /**
+   * Return the keva operation value.  This call is only valid for
+   * OP_KEVA_PUT.
+   * @return The keva operation's value.
+   */
+  inline const valtype& getOpValue() const
+  {
+    switch (op) {
+      case OP_KEVA_PUT:
+        // args[1] is namespace
+        return args[2];
+
+      default:
+        assert (false);
+    }
+  }
+
+  /**
+   * Check if the given script is a keva script.  This is a utility method.
    * @param script The script to parse.
    * @return True iff it is a name script.
    */
   static inline bool
-  isNameScript (const CScript& script)
+  isKevaScript (const CScript& script)
   {
     const CKevaScript op(script);
-    return op.isNameOp ();
+    return op.isKevaOp ();
   }
 
  /**

src/script/script.h

@@ -38,6 +38,8 @@ static const int MAX_STACK_SIZE = 1000;
 // otherwise as UNIX timestamp.
 static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov  5 00:53:20 1985 UTC
 
+typedef std::vector<unsigned char> valtype;
+
 template <typename T>
 std::vector<unsigned char> ToByteVector(const T& in)
 {

src/undo.h

@@ -101,6 +101,9 @@ class CBlockUndo
 public:
     std::vector<CTxUndo> vtxundo; // for all but the coinbase
 
+    /** Stack of operations done to the keva database.  */
+    std::vector<CKevaTxUndo> vkevaundo;
+
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>

src/util.h

@@ -104,6 +104,7 @@ namespace BCLog {
         COINDB      = (1 << 18),
         QT          = (1 << 19),
         LEVELDB     = (1 << 20),
+        KEVA        = (1 << 21),
         ALL         = ~(uint32_t)0,
     };
 }