Refactor: split network transport deserializing from message container

src/net.h

@@ -609,8 +609,33 @@ public:
 
 
 
-
+/** Transport protocol agnostic message container.
+ * Ideally it should only contain receive time, payload,
+ * command and size.
+ */
 class CNetMessage {
+public:
+    CDataStream m_recv;                  // received message data
+    int64_t m_time = 0;                  // time (in microseconds) of message receipt.
+    bool m_valid_netmagic = false;
+    bool m_valid_header = false;
+    bool m_valid_checksum = false;
+    uint32_t m_message_size = 0;         // size of the payload
+    std::string m_command;
+
+    CNetMessage(const CDataStream& recv_in) : m_recv(std::move(recv_in)) {}
+
+    void SetVersion(int nVersionIn)
+    {
+        m_recv.SetVersion(nVersionIn);
+    }
+};
+
+/** The TransportDeserializer takes care of holding and deserializing the
+ * network receive buffer. It can deserialize the network buffer into a
+ * transport protocol agnostic CNetMessage (command & payload)
+ */
+class TransportDeserializer {
 private:
     mutable CHash256 hasher;
     mutable uint256 data_hash;
@@ -624,14 +649,19 @@ public:
     CDataStream vRecv;              // received message data
     unsigned int nDataPos;
 
-    int64_t nTime;                  // time (in microseconds) of message receipt.
+    TransportDeserializer(const CMessageHeader::MessageStartChars& pchMessageStartIn, int nTypeIn, int nVersionIn) : hdrbuf(nTypeIn, nVersionIn), hdr(pchMessageStartIn), vRecv(nTypeIn, nVersionIn) {
+        Reset();
+    }
 
-    CNetMessage(const CMessageHeader::MessageStartChars& pchMessageStartIn, int nTypeIn, int nVersionIn) : hdrbuf(nTypeIn, nVersionIn), hdr(pchMessageStartIn), vRecv(nTypeIn, nVersionIn) {
+    void Reset() {
+        vRecv.clear();
+        hdrbuf.clear();
         hdrbuf.resize(24);
         in_data = false;
         nHdrPos = 0;
         nDataPos = 0;
-        nTime = 0;
+        data_hash.SetNull();
+        hasher.Reset();
     }
 
     bool complete() const
@@ -651,14 +681,17 @@ public:
 
     int readHeader(const char *pch, unsigned int nBytes);
     int readData(const char *pch, unsigned int nBytes);
-};
 
+    CNetMessage GetMessage(const CMessageHeader::MessageStartChars& message_start, int64_t time);
+};
 
 /** Information about a peer */
 class CNode
 {
     friend class CConnman;
 public:
+    std::unique_ptr<TransportDeserializer> m_deserializer;
+
     // socket
     std::atomic<ServiceFlags> nServices{NODE_NONE};
     SOCKET hSocket GUARDED_BY(cs_hSocket);