Merge #19032: Serialization improvements: final step

71f016c6eb42e1ac2c905e04ba4d20c2009e533f Remove old serialization primitives (Pieter Wuille)
92beff15d3ae2646c00bd78146d7592a7097ce9c Convert LimitedString to formatter (Pieter Wuille)
ef17c03e074b6c3f185afa4eff572ba687c2a171 Convert wallet to new serialization (Pieter Wuille)
65c589e45e8b8914698a0fd25cd5aafdda30869c Convert Qt to new serialization (Pieter Wuille)

Pull request description:

  This is the final step 🥳 of the serialization improvements extracted from #10785.

  It converts the LimitedString wrapper to a new-style formatter, and updates the wallet and Qt code to use the new serialization framework. Finally all remaining old primitives are removed.

ACKs for top commit:
  jonatack:
    ACK 71f016c6eb42e1ac2 reviewed diff, builds/tests/re-fuzzed.
  laanwj:
    Code review ACK 71f016c6eb42e1ac2c905e04ba4d20c2009e533f

Tree-SHA512: d952194bc73259f6510bd4ab1348a1febbbf9862af30f905991812fb0e1f23f15948cdb3fc662be54d648e8f6d95b11060055d2e7a8c2cb5bf008224870b1ea1

8 files changed, 87 insertions, 164 deletions

diff --git a/src/qt/recentrequeststablemodel.h b/src/qt/recentrequeststablemodel.h
index addf5ad0ae..c0bd3461bb 100644
--- a/src/qt/recentrequeststablemodel.h
+++ b/src/qt/recentrequeststablemodel.h
@@ -24,19 +24,11 @@ public:
     QDateTime date;
     SendCoinsRecipient recipient;
 
-    ADD_SERIALIZE_METHODS;
-
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
-        unsigned int nDate = date.toTime_t();
-
-        READWRITE(this->nVersion);
-        READWRITE(id);
-        READWRITE(nDate);
-        READWRITE(recipient);
-
-        if (ser_action.ForRead())
-            date = QDateTime::fromTime_t(nDate);
+    SERIALIZE_METHODS(RecentRequestEntry, obj) {
+        unsigned int date_timet;
+        SER_WRITE(obj, date_timet = obj.date.toTime_t());
+        READWRITE(obj.nVersion, obj.id, date_timet, obj.recipient);
+        SER_READ(obj, obj.date = QDateTime::fromTime_t(date_timet));
     }
 };
 
diff --git a/src/qt/sendcoinsrecipient.h b/src/qt/sendcoinsrecipient.h
index 12279fab64..6619faf417 100644
--- a/src/qt/sendcoinsrecipient.h
+++ b/src/qt/sendcoinsrecipient.h
@@ -44,30 +44,21 @@ public:
     static const int CURRENT_VERSION = 1;
     int nVersion;
 
-    ADD_SERIALIZE_METHODS;
+    SERIALIZE_METHODS(SendCoinsRecipient, obj)
+    {
+        std::string address_str, label_str, message_str, auth_merchant_str;
 
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
-        std::string sAddress = address.toStdString();
-        std::string sLabel = label.toStdString();
-        std::string sMessage = message.toStdString();
-        std::string sAuthenticatedMerchant = authenticatedMerchant.toStdString();
+        SER_WRITE(obj, address_str = obj.address.toStdString());
+        SER_WRITE(obj, label_str = obj.label.toStdString());
+        SER_WRITE(obj, message_str = obj.message.toStdString());
+        SER_WRITE(obj, auth_merchant_str = obj.authenticatedMerchant.toStdString());
 
-        READWRITE(this->nVersion);
-        READWRITE(sAddress);
-        READWRITE(sLabel);
-        READWRITE(amount);
-        READWRITE(sMessage);
-        READWRITE(sPaymentRequest);
-        READWRITE(sAuthenticatedMerchant);
+        READWRITE(obj.nVersion, address_str, label_str, obj.amount, message_str, obj.sPaymentRequest, auth_merchant_str);
 
-        if (ser_action.ForRead())
-        {
-            address = QString::fromStdString(sAddress);
-            label = QString::fromStdString(sLabel);
-            message = QString::fromStdString(sMessage);
-            authenticatedMerchant = QString::fromStdString(sAuthenticatedMerchant);
-        }
+        SER_READ(obj, obj.address = QString::fromStdString(address_str));
+        SER_READ(obj, obj.label = QString::fromStdString(label_str));
+        SER_READ(obj, obj.message = QString::fromStdString(message_str));
+        SER_READ(obj, obj.authenticatedMerchant = QString::fromStdString(auth_merchant_str));
     }
 };
 
diff --git a/src/serialize.h b/src/serialize.h
index af75c50ff9..71c2cfa164 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -43,26 +43,6 @@ static const unsigned int MAX_VECTOR_ALLOCATE = 5000000;
 struct deserialize_type {};
 constexpr deserialize_type deserialize {};
 
-/**
- * Used to bypass the rule against non-const reference to temporary
- * where it makes sense with wrappers.
- */
-template<typename T>
-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);
-}
-
 //! Safely convert odd char pointer types to standard ones.
 inline char* CharCast(char* c) { return c; }
 inline char* CharCast(unsigned char* c) { return (char*)c; }
@@ -194,22 +174,6 @@ template<typename X> const X& ReadWriteAsHelper(const X& x) { return x; }
 #define SER_WRITE(obj, code) ::SerWrite(s, ser_action, obj, [&](Stream& s, const Type& obj) { code; })
 
 /**
- * Implement three methods for serializable objects. These are actually wrappers over
- * "SerializationOp" template, which implements the body of each class' serialization
- * code. Adding "ADD_SERIALIZE_METHODS" in the body of the class causes these wrappers to be
- * added as members.
- */
-#define ADD_SERIALIZE_METHODS                                         \
-    template<typename Stream>                                         \
-    void Serialize(Stream& s) const {                                 \
-        NCONST_PTR(this)->SerializationOp(s, CSerActionSerialize());  \
-    }                                                                 \
-    template<typename Stream>                                         \
-    void Unserialize(Stream& s) {                                     \
-        SerializationOp(s, CSerActionUnserialize());                  \
-    }
-
-/**
  * Implement the Ser and Unser methods needed for implementing a formatter (see Using below).
  *
  * Both Ser and Unser are delegated to a single static method SerializationOps, which is polymorphic
@@ -503,7 +467,7 @@ static inline Wrapper<Formatter, T&> Using(T&& t) { return Wrapper<Formatter, T&
 #define VARINT_MODE(obj, mode) Using<VarIntFormatter<mode>>(obj)
 #define VARINT(obj) Using<VarIntFormatter<VarIntMode::DEFAULT>>(obj)
 #define COMPACTSIZE(obj) Using<CompactSizeFormatter>(obj)
-#define LIMITED_STRING(obj,n) LimitedString< n >(REF(obj))
+#define LIMITED_STRING(obj,n) Using<LimitedStringFormatter<n>>(obj)
 
 /** Serialization wrapper class for integers in VarInt format. */
 template<VarIntMode Mode>
@@ -588,31 +552,23 @@ struct CompactSizeFormatter
 };
 
 template<size_t Limit>
-class LimitedString
+struct LimitedStringFormatter
 {
-protected:
-    std::string& string;
-public:
-    explicit LimitedString(std::string& _string) : string(_string) {}
-
     template<typename Stream>
-    void Unserialize(Stream& s)
+    void Unser(Stream& s, std::string& v)
     {
         size_t size = ReadCompactSize(s);
         if (size > Limit) {
             throw std::ios_base::failure("String length limit exceeded");
         }
-        string.resize(size);
-        if (size != 0)
-            s.read((char*)string.data(), size);
+        v.resize(size);
+        if (size != 0) s.read((char*)v.data(), size);
     }
 
     template<typename Stream>
-    void Serialize(Stream& s) const
+    void Ser(Stream& s, const std::string& v)
     {
-        WriteCompactSize(s, string.size());
-        if (!string.empty())
-            s.write((char*)string.data(), string.size());
+        s << v;
     }
 };
 
@@ -1012,7 +968,7 @@ void Unserialize(Stream& is, std::shared_ptr<const T>& p)
 
 
 /**
- * Support for ADD_SERIALIZE_METHODS and READWRITE macro
+ * Support for SERIALIZE_METHODS and READWRITE macro.
  */
 struct CSerActionSerialize
 {
diff --git a/src/test/fuzz/string.cpp b/src/test/fuzz/string.cpp
index 3c1f911f7e..50984b1aef 100644
--- a/src/test/fuzz/string.cpp
+++ b/src/test/fuzz/string.cpp
@@ -93,7 +93,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     {
         CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
         std::string s;
-        LimitedString<10> limited_string = LIMITED_STRING(s, 10);
+        auto limited_string = LIMITED_STRING(s, 10);
         data_stream << random_string_1;
         try {
             data_stream >> limited_string;
@@ -108,7 +108,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     }
     {
         CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
-        const LimitedString<10> limited_string = LIMITED_STRING(random_string_1, 10);
+        const auto limited_string = LIMITED_STRING(random_string_1, 10);
         data_stream << limited_string;
         std::string deserialized_string;
         data_stream >> deserialized_string;
diff --git a/src/wallet/crypter.h b/src/wallet/crypter.h
index f59c63260e..f2df786e2e 100644
--- a/src/wallet/crypter.h
+++ b/src/wallet/crypter.h
@@ -43,15 +43,9 @@ public:
     //! such as the various parameters to scrypt
     std::vector<unsigned char> vchOtherDerivationParameters;
 
-    ADD_SERIALIZE_METHODS;
-
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
-        READWRITE(vchCryptedKey);
-        READWRITE(vchSalt);
-        READWRITE(nDerivationMethod);
-        READWRITE(nDeriveIterations);
-        READWRITE(vchOtherDerivationParameters);
+    SERIALIZE_METHODS(CMasterKey, obj)
+    {
+        READWRITE(obj.vchCryptedKey, obj.vchSalt, obj.nDerivationMethod, obj.nDeriveIterations, obj.vchOtherDerivationParameters);
     }
 
     CMasterKey()
diff --git a/src/wallet/scriptpubkeyman.h b/src/wallet/scriptpubkeyman.h
index 2f6245bbe2..d62d30f339 100644
--- a/src/wallet/scriptpubkeyman.h
+++ b/src/wallet/scriptpubkeyman.h
@@ -112,36 +112,37 @@ public:
     CKeyPool();
     CKeyPool(const CPubKey& vchPubKeyIn, bool internalIn);
 
-    ADD_SERIALIZE_METHODS;
+    template<typename Stream>
+    void Serialize(Stream& s) const
+    {
+        int nVersion = s.GetVersion();
+        if (!(s.GetType() & SER_GETHASH)) {
+            s << nVersion;
+        }
+        s << nTime << vchPubKey << fInternal << m_pre_split;
+    }
 
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
+    template<typename Stream>
+    void Unserialize(Stream& s)
+    {
         int nVersion = s.GetVersion();
-        if (!(s.GetType() & SER_GETHASH))
-            READWRITE(nVersion);
-        READWRITE(nTime);
-        READWRITE(vchPubKey);
-        if (ser_action.ForRead()) {
-            try {
-                READWRITE(fInternal);
-            }
-            catch (std::ios_base::failure&) {
-                /* flag as external address if we can't read the internal boolean
-                   (this will be the case for any wallet before the HD chain split version) */
-                fInternal = false;
-            }
-            try {
-                READWRITE(m_pre_split);
-            }
-            catch (std::ios_base::failure&) {
-                /* flag as postsplit address if we can't read the m_pre_split boolean
-                   (this will be the case for any wallet that upgrades to HD chain split)*/
-                m_pre_split = false;
-            }
+        if (!(s.GetType() & SER_GETHASH)) {
+            s >> nVersion;
+        }
+        s >> nTime >> vchPubKey;
+        try {
+            s >> fInternal;
+        } catch (std::ios_base::failure&) {
+            /* flag as external address if we can't read the internal boolean
+               (this will be the case for any wallet before the HD chain split version) */
+            fInternal = false;
         }
-        else {
-            READWRITE(fInternal);
-            READWRITE(m_pre_split);
+        try {
+            s >> m_pre_split;
+        } catch (std::ios_base::failure&) {
+            /* flag as postsplit address if we can't read the m_pre_split boolean
+               (this will be the case for any wallet that upgrades to HD chain split) */
+            m_pre_split = false;
         }
     }
 };
diff --git a/src/wallet/walletdb.h b/src/wallet/walletdb.h
index ee1a8cd5b2..a2788ed6c4 100644
--- a/src/wallet/walletdb.h
+++ b/src/wallet/walletdb.h
@@ -98,15 +98,13 @@ public:
     int nVersion;
 
     CHDChain() { SetNull(); }
-    ADD_SERIALIZE_METHODS;
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action)
+
+    SERIALIZE_METHODS(CHDChain, obj)
     {
-        READWRITE(this->nVersion);
-        READWRITE(nExternalChainCounter);
-        READWRITE(seed_id);
-        if (this->nVersion >= VERSION_HD_CHAIN_SPLIT)
-            READWRITE(nInternalChainCounter);
+        READWRITE(obj.nVersion, obj.nExternalChainCounter, obj.seed_id);
+        if (obj.nVersion >= VERSION_HD_CHAIN_SPLIT) {
+            READWRITE(obj.nInternalChainCounter);
+        }
     }
 
     void SetNull()
@@ -147,21 +145,16 @@ public:
         nCreateTime = nCreateTime_;
     }
 
-    ADD_SERIALIZE_METHODS;
-
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
-        READWRITE(this->nVersion);
-        READWRITE(nCreateTime);
-        if (this->nVersion >= VERSION_WITH_HDDATA)
-        {
-            READWRITE(hdKeypath);
-            READWRITE(hd_seed_id);
+    SERIALIZE_METHODS(CKeyMetadata, obj)
+    {
+        READWRITE(obj.nVersion, obj.nCreateTime);
+        if (obj.nVersion >= VERSION_WITH_HDDATA) {
+            READWRITE(obj.hdKeypath, obj.hd_seed_id);
         }
-        if (this->nVersion >= VERSION_WITH_KEY_ORIGIN)
+        if (obj.nVersion >= VERSION_WITH_KEY_ORIGIN)
         {
-            READWRITE(key_origin);
-            READWRITE(has_key_origin);
+            READWRITE(obj.key_origin);
+            READWRITE(obj.has_key_origin);
         }
     }
 
diff --git a/src/wallet/walletutil.h b/src/wallet/walletutil.h
index 599b1a9f5a..a4e4fda8a1 100644
--- a/src/wallet/walletutil.h
+++ b/src/wallet/walletutil.h
@@ -98,26 +98,22 @@ public:
     int32_t next_index = 0; // Position of the next item to generate
     DescriptorCache cache;
 
-    ADD_SERIALIZE_METHODS;
-
-    template <typename Stream, typename Operation>
-    inline void SerializationOp(Stream& s, Operation ser_action) {
-        if (ser_action.ForRead()) {
-            std::string desc;
-            std::string error;
-            READWRITE(desc);
-            FlatSigningProvider keys;
-            descriptor = Parse(desc, keys, error, true);
-            if (!descriptor) {
-                throw std::ios_base::failure("Invalid descriptor: " + error);
-            }
-        } else {
-            READWRITE(descriptor->ToString());
+    void DeserializeDescriptor(const std::string& str)
+    {
+        std::string error;
+        FlatSigningProvider keys;
+        descriptor = Parse(str, keys, error, true);
+        if (!descriptor) {
+            throw std::ios_base::failure("Invalid descriptor: " + error);
         }
-        READWRITE(creation_time);
-        READWRITE(next_index);
-        READWRITE(range_start);
-        READWRITE(range_end);
+    }
+
+    SERIALIZE_METHODS(WalletDescriptor, obj)
+    {
+        std::string descriptor_str;
+        SER_WRITE(obj, descriptor_str = obj.descriptor->ToString());
+        READWRITE(descriptor_str, obj.creation_time, obj.next_index, obj.range_start, obj.range_end);
+        SER_READ(obj, obj.DeserializeDescriptor(descriptor_str));
     }
 
     WalletDescriptor() {}