Merge pull request #4737

31e9a83 Use CSizeComputer to avoid counting sizes in SerializationOp (Pieter Wuille)
84881f8 rework overhauled serialization methods to non-static (Kamil Domanski)
5d96b4a remove fields of ser_streamplaceholder (Kamil Domanski)
3d796f8 overhaul serialization code (Kamil Domanski)

13 files changed, 271 insertions, 193 deletions

diff --git a/src/addrman.h b/src/addrman.h
index 8f6ab60662..0790802b5c 100644
--- a/src/addrman.h
+++ b/src/addrman.h
@@ -46,13 +46,15 @@ private:
 
 public:
 
-    IMPLEMENT_SERIALIZE(
-        CAddress* pthis = (CAddress*)(this);
-        READWRITE(*pthis);
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        READWRITE(*(CAddress*)this);
         READWRITE(source);
         READWRITE(nLastSuccess);
         READWRITE(nAttempts);
-    )
+    }
 
     void Init()
     {
diff --git a/src/alert.h b/src/alert.h
index d8254ba2cb..4a8736d60b 100644
--- a/src/alert.h
+++ b/src/alert.h
@@ -46,8 +46,10 @@ public:
     std::string strStatusBar;
     std::string strReserved;
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(this->nVersion);
         nVersion = this->nVersion;
         READWRITE(nRelayUntil);
@@ -63,7 +65,7 @@ public:
         READWRITE(LIMITED_STRING(strComment, 65536));
         READWRITE(LIMITED_STRING(strStatusBar, 256));
         READWRITE(LIMITED_STRING(strReserved, 256));
-    )
+    }
 
     void SetNull();
 
@@ -82,11 +84,13 @@ public:
         SetNull();
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(vchMsg);
         READWRITE(vchSig);
-    )
+    }
 
     void SetNull();
     bool IsNull() const;
diff --git a/src/bloom.h b/src/bloom.h
index bedd8fbcd8..4a710928cc 100644
--- a/src/bloom.h
+++ b/src/bloom.h
@@ -62,13 +62,15 @@ public:
     CBloomFilter(unsigned int nElements, double nFPRate, unsigned int nTweak, unsigned char nFlagsIn);
     CBloomFilter() : isFull(true), isEmpty(false), nHashFuncs(0), nTweak(0), nFlags(0) {}
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(vData);
         READWRITE(nHashFuncs);
         READWRITE(nTweak);
         READWRITE(nFlags);
-    )
+    }
 
     void insert(const std::vector<unsigned char>& vKey);
     void insert(const COutPoint& outpoint);
diff --git a/src/core.h b/src/core.h
index a3ec2346e2..34c00c4142 100644
--- a/src/core.h
+++ b/src/core.h
@@ -30,7 +30,14 @@ public:
 
     COutPoint() { SetNull(); }
     COutPoint(uint256 hashIn, uint32_t nIn) { hash = hashIn; n = nIn; }
-    IMPLEMENT_SERIALIZE( READWRITE(FLATDATA(*this)); )
+
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        READWRITE(FLATDATA(*this));
+    }
+
     void SetNull() { hash = 0; n = (uint32_t) -1; }
     bool IsNull() const { return (hash == 0 && n == (uint32_t) -1); }
 
@@ -84,12 +91,14 @@ public:
     explicit CTxIn(COutPoint prevoutIn, CScript scriptSigIn=CScript(), uint32_t nSequenceIn=std::numeric_limits<unsigned int>::max());
     CTxIn(uint256 hashPrevTx, uint32_t nOut, CScript scriptSigIn=CScript(), uint32_t nSequenceIn=std::numeric_limits<uint32_t>::max());
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(prevout);
         READWRITE(scriptSig);
         READWRITE(nSequence);
-    )
+    }
 
     bool IsFinal() const
     {
@@ -136,7 +145,12 @@ public:
     friend bool operator>=(const CFeeRate& a, const CFeeRate& b) { return a.nSatoshisPerK >= b.nSatoshisPerK; }
     std::string ToString() const;
 
-    IMPLEMENT_SERIALIZE( READWRITE(nSatoshisPerK); )
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        READWRITE(nSatoshisPerK);
+    }
 };
 
 
@@ -156,11 +170,13 @@ public:
 
     CTxOut(int64_t nValueIn, CScript scriptPubKeyIn);
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(nValue);
         READWRITE(scriptPubKey);
-    )
+    }
 
     void SetNull()
     {
@@ -237,7 +253,12 @@ public:
 
     CTransaction& operator=(const CTransaction& tx);
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         READWRITE(*const_cast<int32_t*>(&this->nVersion));
         nVersion = this->nVersion;
         READWRITE(*const_cast<std::vector<CTxIn>*>(&vin));
@@ -245,7 +266,7 @@ public:
         READWRITE(*const_cast<uint32_t*>(&nLockTime));
         if (fRead)
             UpdateHash();
-    )
+    }
 
     bool IsNull() const {
         return vin.empty() && vout.empty();
@@ -292,13 +313,16 @@ struct CMutableTransaction
     CMutableTransaction();
     CMutableTransaction(const CTransaction& tx);
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(this->nVersion);
         nVersion = this->nVersion;
         READWRITE(vin);
         READWRITE(vout);
         READWRITE(nLockTime);
-    )
+    }
 
     /** Compute the hash of this CMutableTransaction. This is computed on the
      * fly, as opposed to GetHash() in CTransaction, which uses a cached result.
@@ -318,7 +342,11 @@ public:
 
     CTxOutCompressor(CTxOut &txoutIn) : txout(txoutIn) { }
 
-    IMPLEMENT_SERIALIZE(({
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
         if (!fRead) {
             uint64_t nVal = CompressAmount(txout.nValue);
             READWRITE(VARINT(nVal));
@@ -329,7 +357,7 @@ public:
         }
         CScriptCompressor cscript(REF(txout.scriptPubKey));
         READWRITE(cscript);
-    });)
+    }
 };
 
 /** Undo information for a CTxIn
@@ -382,9 +410,12 @@ public:
     // undo information for all txins
     std::vector<CTxInUndo> vprevout;
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(vprevout);
-    )
+    }
 };
 
 
@@ -412,8 +443,10 @@ public:
         SetNull();
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(this->nVersion);
         nVersion = this->nVersion;
         READWRITE(hashPrevBlock);
@@ -421,7 +454,7 @@ public:
         READWRITE(nTime);
         READWRITE(nBits);
         READWRITE(nNonce);
-    )
+    }
 
     void SetNull()
     {
@@ -467,11 +500,13 @@ public:
         *((CBlockHeader*)this) = header;
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(*(CBlockHeader*)this);
         READWRITE(vtx);
-    )
+    }
 
     void SetNull()
     {
@@ -515,12 +550,14 @@ struct CBlockLocator
         vHave = vHaveIn;
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         if (!(nType & SER_GETHASH))
             READWRITE(nVersion);
         READWRITE(vHave);
-    )
+    }
 
     void SetNull()
     {
diff --git a/src/crypter.h b/src/crypter.h
index 9b592dbcdc..59efc76508 100644
--- a/src/crypter.h
+++ b/src/crypter.h
@@ -43,14 +43,17 @@ public:
     // such as the various parameters to scrypt
     std::vector<unsigned char> vchOtherDerivationParameters;
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(vchCryptedKey);
         READWRITE(vchSalt);
         READWRITE(nDerivationMethod);
         READWRITE(nDeriveIterations);
         READWRITE(vchOtherDerivationParameters);
-    )
+    }
+
     CMasterKey()
     {
         // 25000 rounds is just under 0.1 seconds on a 1.86 GHz Pentium M
diff --git a/src/main.h b/src/main.h
index e0836960b3..31a1131b83 100644
--- a/src/main.h
+++ b/src/main.h
@@ -197,10 +197,13 @@ struct CDiskBlockPos
     int nFile;
     unsigned int nPos;
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(VARINT(nFile));
         READWRITE(VARINT(nPos));
-    )
+    }
 
     CDiskBlockPos() {
         SetNull();
@@ -227,10 +230,13 @@ struct CDiskTxPos : public CDiskBlockPos
 {
     unsigned int nTxOffset; // after header
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(*(CDiskBlockPos*)this);
         READWRITE(VARINT(nTxOffset));
-    )
+    }
 
     CDiskTxPos(const CDiskBlockPos &blockIn, unsigned int nTxOffsetIn) : CDiskBlockPos(blockIn.nFile, blockIn.nPos), nTxOffset(nTxOffsetIn) {
     }
@@ -307,9 +313,12 @@ class CBlockUndo
 public:
     std::vector<CTxUndo> vtxundo; // for all but the coinbase
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(vtxundo);
-    )
+    }
 
     bool WriteToDisk(CDiskBlockPos &pos, const uint256 &hashBlock);
     bool ReadFromDisk(const CDiskBlockPos &pos, const uint256 &hashBlock);
@@ -411,7 +420,12 @@ protected:
 public:
 
     // serialization implementation
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         READWRITE(nTransactions);
         READWRITE(vHash);
         std::vector<unsigned char> vBytes;
@@ -428,7 +442,7 @@ public:
                 vBytes[p / 8] |= vBits[p] << (p % 8);
             READWRITE(vBytes);
         }
-    )
+    }
 
     // Construct a partial merkle tree from a list of transaction id's, and a mask that selects a subset of them
     CPartialMerkleTree(const std::vector<uint256> &vTxid, const std::vector<bool> &vMatch);
@@ -484,7 +498,10 @@ public:
     uint64_t nTimeFirst;         // earliest time of block in file
     uint64_t nTimeLast;          // latest time of block in file
 
-    IMPLEMENT_SERIALIZE(
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(VARINT(nBlocks));
         READWRITE(VARINT(nSize));
         READWRITE(VARINT(nUndoSize));
@@ -492,7 +509,7 @@ public:
         READWRITE(VARINT(nHeightLast));
         READWRITE(VARINT(nTimeFirst));
         READWRITE(VARINT(nTimeLast));
-     )
+    }
 
      void SetNull() {
          nBlocks = 0;
@@ -755,8 +772,10 @@ public:
         hashPrev = (pprev ? pprev->GetBlockHash() : 0);
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         if (!(nType & SER_GETHASH))
             READWRITE(VARINT(nVersion));
 
@@ -777,7 +796,7 @@ public:
         READWRITE(nTime);
         READWRITE(nBits);
         READWRITE(nNonce);
-    )
+    }
 
     uint256 GetBlockHash() const
     {
@@ -975,11 +994,13 @@ public:
     // thus the filter will likely be modified.
     CMerkleBlock(const CBlock& block, CBloomFilter& filter);
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(header);
         READWRITE(txn);
-    )
+    }
 };
 
 
diff --git a/src/netbase.h b/src/netbase.h
index d4d266e0a8..9b52c0a415 100644
--- a/src/netbase.h
+++ b/src/netbase.h
@@ -88,10 +88,12 @@ class CNetAddr
         friend bool operator!=(const CNetAddr& a, const CNetAddr& b);
         friend bool operator<(const CNetAddr& a, const CNetAddr& b);
 
-        IMPLEMENT_SERIALIZE
-            (
-             READWRITE(FLATDATA(ip));
-            )
+        IMPLEMENT_SERIALIZE;
+
+        template <typename Stream, typename Operation>
+        inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+            READWRITE(FLATDATA(ip));
+        }
 };
 
 class CSubNet
@@ -148,15 +150,17 @@ class CService : public CNetAddr
         CService(const struct in6_addr& ipv6Addr, unsigned short port);
         CService(const struct sockaddr_in6& addr);
 
-        IMPLEMENT_SERIALIZE
-            (
-             CService* pthis = const_cast<CService*>(this);
-             READWRITE(FLATDATA(ip));
-             unsigned short portN = htons(port);
-             READWRITE(portN);
-             if (fRead)
-                 pthis->port = ntohs(portN);
-            )
+        IMPLEMENT_SERIALIZE;
+
+        template <typename Stream, typename Operation>
+        inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+            bool fRead = ser_action.ForRead();
+            READWRITE(FLATDATA(ip));
+            unsigned short portN = htons(port);
+            READWRITE(portN);
+            if (fRead)
+                 port = ntohs(portN);
+        }
 };
 
 typedef CService proxyType;
diff --git a/src/protocol.h b/src/protocol.h
index d7565584af..e4b0991774 100644
--- a/src/protocol.h
+++ b/src/protocol.h
@@ -35,13 +35,15 @@ class CMessageHeader
         std::string GetCommand() const;
         bool IsValid() const;
 
-        IMPLEMENT_SERIALIZE
-            (
-             READWRITE(FLATDATA(pchMessageStart));
-             READWRITE(FLATDATA(pchCommand));
-             READWRITE(nMessageSize);
-             READWRITE(nChecksum);
-            )
+        IMPLEMENT_SERIALIZE;
+
+        template <typename Stream, typename Operation>
+        inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+            READWRITE(FLATDATA(pchMessageStart));
+            READWRITE(FLATDATA(pchCommand));
+            READWRITE(nMessageSize);
+            READWRITE(nChecksum);
+        }
 
     // TODO: make private (improves encapsulation)
     public:
@@ -83,20 +85,23 @@ class CAddress : public CService
 
         void Init();
 
-        IMPLEMENT_SERIALIZE
-            (
-             CAddress* pthis = const_cast<CAddress*>(this);
-             CService* pip = (CService*)pthis;
-             if (fRead)
-                 pthis->Init();
-             if (nType & SER_DISK)
-                 READWRITE(nVersion);
-             if ((nType & SER_DISK) ||
-                 (nVersion >= CADDR_TIME_VERSION && !(nType & SER_GETHASH)))
-                 READWRITE(nTime);
-             READWRITE(nServices);
-             READWRITE(*pip);
-            )
+        IMPLEMENT_SERIALIZE;
+
+        template <typename Stream, typename Operation>
+        inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+            bool fRead = ser_action.ForRead();
+
+            CAddress* pthis = const_cast<CAddress*>(this);
+            if (fRead)
+                pthis->Init();
+            if (nType & SER_DISK)
+                READWRITE(nVersion);
+            if ((nType & SER_DISK) ||
+                (nVersion >= CADDR_TIME_VERSION && !(nType & SER_GETHASH)))
+            READWRITE(nTime);
+            READWRITE(nServices);
+            READWRITE(*(CService*)this);
+        }
 
     // TODO: make private (improves encapsulation)
     public:
@@ -117,11 +122,13 @@ class CInv
         CInv(int typeIn, const uint256& hashIn);
         CInv(const std::string& strType, const uint256& hashIn);
 
-        IMPLEMENT_SERIALIZE
-        (
+        IMPLEMENT_SERIALIZE;
+
+        template <typename Stream, typename Operation>
+        inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
             READWRITE(type);
             READWRITE(hash);
-        )
+        }
 
         friend bool operator<(const CInv& a, const CInv& b);
 
diff --git a/src/qt/recentrequeststablemodel.h b/src/qt/recentrequeststablemodel.h
index 4f0b241259..a558aa4942 100644
--- a/src/qt/recentrequeststablemodel.h
+++ b/src/qt/recentrequeststablemodel.h
@@ -24,8 +24,12 @@ public:
     QDateTime date;
     SendCoinsRecipient recipient;
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         RecentRequestEntry* pthis = const_cast<RecentRequestEntry*>(this);
 
         unsigned int nDate = date.toTime_t();
@@ -37,8 +41,8 @@ public:
         READWRITE(recipient);
 
         if (fRead)
-            pthis->date = QDateTime::fromTime_t(nDate);
-    )
+            date = QDateTime::fromTime_t(nDate);
+    }
 };
 
 class RecentRequestEntryLessThan
diff --git a/src/qt/walletmodel.h b/src/qt/walletmodel.h
index b3a401e4cc..2a9ac4650f 100644
--- a/src/qt/walletmodel.h
+++ b/src/qt/walletmodel.h
@@ -59,8 +59,12 @@ public:
     static const int CURRENT_VERSION = 1;
     int nVersion;
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         SendCoinsRecipient* pthis = const_cast<SendCoinsRecipient*>(this);
 
         std::string sAddress = pthis->address.toStdString();
@@ -89,7 +93,7 @@ public:
                 pthis->paymentRequest.parse(QByteArray::fromRawData(sPaymentRequest.data(), sPaymentRequest.size()));
             pthis->authenticatedMerchant = QString::fromStdString(sAuthenticatedMerchant);
         }
-    )
+    }
 };
 
 /** Interface to Bitcoin wallet from Qt view code. */
diff --git a/src/serialize.h b/src/serialize.h
index d486181d78..1440676a16 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -37,6 +37,14 @@ inline T& REF(const T& val)
     return const_cast<T&>(val);
 }
 
+// Used to acquire a non-const pointer "this" to generate bodies
+// of const serialization operations from a template
+template<typename T>
+inline T* NCONST_PTR(const T* val)
+{
+    return const_cast<T*>(val);
+}
+
 /** Get begin pointer of vector (non-const version).
  * @note These functions avoid the undefined case of indexing into an empty
  * vector, as well as that of indexing after the end of the vector.
@@ -79,48 +87,26 @@ enum
     SER_GETHASH         = (1 << 2),
 };
 
-#define IMPLEMENT_SERIALIZE(statements)    \
-    unsigned int GetSerializeSize(int nType, int nVersion) const  \
-    {                                           \
-        CSerActionGetSerializeSize ser_action;  \
-        const bool fGetSize = true;             \
-        const bool fWrite = false;              \
-        const bool fRead = false;               \
-        unsigned int nSerSize = 0;              \
-        ser_streamplaceholder s;                \
-        assert(fGetSize||fWrite||fRead); /* suppress warning */ \
-        s.nType = nType;                        \
-        s.nVersion = nVersion;                  \
-        {statements}                            \
-        return nSerSize;                        \
-    }                                           \
-    template<typename Stream>                   \
-    void Serialize(Stream& s, int nType, int nVersion) const  \
-    {                                           \
-        CSerActionSerialize ser_action;         \
-        const bool fGetSize = false;            \
-        const bool fWrite = true;               \
-        const bool fRead = false;               \
-        unsigned int nSerSize = 0;              \
-        assert(fGetSize||fWrite||fRead); /* suppress warning */ \
-        {statements}                            \
-    }                                           \
-    template<typename Stream>                   \
-    void Unserialize(Stream& s, int nType, int nVersion)  \
-    {                                           \
-        CSerActionUnserialize ser_action;       \
-        const bool fGetSize = false;            \
-        const bool fWrite = false;              \
-        const bool fRead = true;                \
-        unsigned int nSerSize = 0;              \
-        assert(fGetSize||fWrite||fRead); /* suppress warning */ \
-        {statements}                            \
-    }
-
-#define READWRITE(obj)      (nSerSize += ::SerReadWrite(s, (obj), nType, nVersion, ser_action))
-
-
+#define READWRITE(obj)      (::SerReadWrite(s, (obj), nType, nVersion, ser_action))
 
+/* Implement three methods for serializable objects. These are actually wrappers over
+ * "SerializationOp" template, which implements the body of each class' serialization
+ * code. Adding "IMPLEMENT_SERIALIZE" in the body of the class causes these wrappers to be
+ * added as members. */
+#define IMPLEMENT_SERIALIZE                                                          \
+    size_t GetSerializeSize(int nType, int nVersion) const {                         \
+        CSizeComputer s(nType, nVersion);                                            \
+        NCONST_PTR(this)->SerializationOp(s, CSerActionSerialize(), nType, nVersion);\
+        return s.size();                                                             \
+    }                                                                                \
+    template<typename Stream>                                                        \
+    void Serialize(Stream& s, int nType, int nVersion) const {                       \
+        NCONST_PTR(this)->SerializationOp(s, CSerActionSerialize(), nType, nVersion);\
+    }                                                                                \
+    template<typename Stream>                                                        \
+    void Unserialize(Stream& s, int nType, int nVersion) {                           \
+        SerializationOp(s, CSerActionUnserialize(), nType, nVersion);                \
+    }
 
 
 
@@ -823,38 +809,27 @@ void Unserialize(Stream& is, std::set<K, Pred, A>& m, int nType, int nVersion)
 //
 // Support for IMPLEMENT_SERIALIZE and READWRITE macro
 //
-class CSerActionGetSerializeSize { };
-class CSerActionSerialize { };
-class CSerActionUnserialize { };
-
-template<typename Stream, typename T>
-inline unsigned int SerReadWrite(Stream& s, const T& obj, int nType, int nVersion, CSerActionGetSerializeSize ser_action)
+struct CSerActionSerialize
 {
-    return ::GetSerializeSize(obj, nType, nVersion);
-}
+    bool ForRead() const { return false; }
+};
+struct CSerActionUnserialize
+{
+    bool ForRead() const { return true; }
+};
 
 template<typename Stream, typename T>
-inline unsigned int SerReadWrite(Stream& s, const T& obj, int nType, int nVersion, CSerActionSerialize ser_action)
+inline void SerReadWrite(Stream& s, const T& obj, int nType, int nVersion, CSerActionSerialize ser_action)
 {
     ::Serialize(s, obj, nType, nVersion);
-    return 0;
 }
 
 template<typename Stream, typename T>
-inline unsigned int SerReadWrite(Stream& s, T& obj, int nType, int nVersion, CSerActionUnserialize ser_action)
+inline void SerReadWrite(Stream& s, T& obj, int nType, int nVersion, CSerActionUnserialize ser_action)
 {
     ::Unserialize(s, obj, nType, nVersion);
-    return 0;
 }
 
-struct ser_streamplaceholder
-{
-    int nType;
-    int nVersion;
-};
-
-
-
 
 
 
diff --git a/src/wallet.h b/src/wallet.h
index 41b4b1917c..cea61afed3 100644
--- a/src/wallet.h
+++ b/src/wallet.h
@@ -64,13 +64,15 @@ public:
     CKeyPool();
     CKeyPool(const CPubKey& vchPubKeyIn);
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         if (!(nType & SER_GETHASH))
             READWRITE(nVersion);
         READWRITE(nTime);
         READWRITE(vchPubKey);
-    )
+    }
 };
 
 /** Address book data */
@@ -490,16 +492,16 @@ public:
         fMerkleVerified = false;
     }
 
+    IMPLEMENT_SERIALIZE;
 
-    IMPLEMENT_SERIALIZE
-    (
-        nSerSize += SerReadWrite(s, *(CTransaction*)this, nType, nVersion, ser_action);
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        READWRITE(*(CTransaction*)this);
         nVersion = this->nVersion;
         READWRITE(hashBlock);
         READWRITE(vMerkleBranch);
         READWRITE(nIndex);
-    )
-
+    }
 
     int SetMerkleBranch(const CBlock* pblock=NULL);
 
@@ -514,7 +516,6 @@ public:
     bool AcceptToMemoryPool(bool fLimitFree=true, bool fRejectInsaneFee=true);
 };
 
-
 /** A transaction with a bunch of additional info that only the owner cares about.
  * It includes any unrecorded transactions needed to link it back to the block chain.
  */
@@ -604,8 +605,12 @@ public:
         nOrderPos = -1;
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         CWalletTx* pthis = const_cast<CWalletTx*>(this);
         if (fRead)
             pthis->Init(NULL);
@@ -621,7 +626,7 @@ public:
                 pthis->mapValue["timesmart"] = strprintf("%u", nTimeSmart);
         }
 
-        nSerSize += SerReadWrite(s, *(CMerkleTx*)this, nType, nVersion,ser_action);
+        READWRITE(*(CMerkleTx*)this);
         std::vector<CMerkleTx> vUnused; // Used to be vtxPrev
         READWRITE(vUnused);
         READWRITE(mapValue);
@@ -640,12 +645,12 @@ public:
             pthis->nTimeSmart = mapValue.count("timesmart") ? (unsigned int)atoi64(pthis->mapValue["timesmart"]) : 0;
         }
 
-        pthis->mapValue.erase("fromaccount");
-        pthis->mapValue.erase("version");
-        pthis->mapValue.erase("spent");
-        pthis->mapValue.erase("n");
-        pthis->mapValue.erase("timesmart");
-    )
+        mapValue.erase("fromaccount");
+        mapValue.erase("version");
+        mapValue.erase("spent");
+        mapValue.erase("n");
+        mapValue.erase("timesmart");
+    }
 
     // make sure balances are recalculated
     void MarkDirty()
@@ -891,15 +896,17 @@ public:
 
     CWalletKey(int64_t nExpires=0);
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         if (!(nType & SER_GETHASH))
             READWRITE(nVersion);
         READWRITE(vchPrivKey);
         READWRITE(nTimeCreated);
         READWRITE(nTimeExpires);
         READWRITE(LIMITED_STRING(strComment, 65536));
-    )
+    }
 };
 
 
@@ -925,12 +932,14 @@ public:
         vchPubKey = CPubKey();
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         if (!(nType & SER_GETHASH))
             READWRITE(nVersion);
         READWRITE(vchPubKey);
-    )
+    }
 };
 
 
@@ -966,8 +975,12 @@ public:
         nEntryNo = 0;
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        bool fRead = ser_action.ForRead();
+
         CAccountingEntry& me = *const_cast<CAccountingEntry*>(this);
         if (!(nType & SER_GETHASH))
             READWRITE(nVersion);
@@ -1007,8 +1020,8 @@ public:
         if (std::string::npos != nSepPos)
             me.strComment.erase(nSepPos);
 
-        me.mapValue.erase("n");
-    )
+        mapValue.erase("n");
+    }
 
 private:
     std::vector<char> _ssExtra;
diff --git a/src/walletdb.h b/src/walletdb.h
index 24096e13ea..cf1a66216e 100644
--- a/src/walletdb.h
+++ b/src/walletdb.h
@@ -55,12 +55,14 @@ public:
         nCreateTime = nCreateTime_;
     }
 
-    IMPLEMENT_SERIALIZE
-    (
+    IMPLEMENT_SERIALIZE;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(this->nVersion);
         nVersion = this->nVersion;
         READWRITE(nCreateTime);
-    )
+    }
 
     void SetNull()
     {