Merge bitcoin/bitcoin#35148: refactor: Remove confusing DataStream::in_avail() alias

fa204100e1 streams: Remove confusing DataStream::in_avail() (MarcoFalke)
fa5ab0220e move-only: Extract ProcessPong() helper (MarcoFalke)

Pull request description:

  The `in_avail` alias is confusing (see commit message), so remove it. Also extract the `ProcessPong()` helper, as the only place that called `in_avail`.

ACKs for top commit:
  l0rinc:
    code review ACK fa204100e1
  sedited:
    ACK fa204100e1

Tree-SHA512: b5a069abb471c42d39e91a3c55fc7f18fb9ccf8591408b3dd43210d0287785369b6a5d6b59b847d85247a494f208dbbe4a7e88b24caf9b3e6c8fea2157cd0ee0

src/net_processing.cpp

@@ -1075,6 +1075,8 @@ private:
      */
     void ProcessGetCFCheckPt(CNode& node, Peer& peer, DataStream& vRecv);
 
+    void ProcessPong(CNode& pfrom, Peer& peer, NodeClock::time_point ping_end, DataStream& vRecv);
+
     /** Checks if address relay is permitted with peer. If needed, initializes
      * the m_addr_known bloom filter and sets m_addr_relay_enabled to true.
      *
@@ -4902,63 +4904,7 @@ void PeerManagerImpl::ProcessMessage(Peer& peer, CNode& pfrom, const std::string
     }
 
     if (msg_type == NetMsgType::PONG) {
-        const auto ping_end{time_received};
-        uint64_t nonce = 0;
-        size_t nAvail = vRecv.in_avail();
-        bool bPingFinished = false;
-        std::string sProblem;
-
-        if (nAvail >= sizeof(nonce)) {
-            vRecv >> nonce;
-
-            // Only process pong message if there is an outstanding ping (old ping without nonce should never pong)
-            if (peer.m_ping_nonce_sent != 0) {
-                if (nonce == peer.m_ping_nonce_sent) {
-                    // Matching pong received, this ping is no longer outstanding
-                    bPingFinished = true;
-                    const auto ping_time = ping_end - peer.m_ping_start.load();
-                    if (ping_time.count() >= 0) {
-                        // Let connman know about this successful ping-pong
-                        pfrom.PongReceived(ping_time);
-                        if (pfrom.IsPrivateBroadcastConn()) {
-                            m_tx_for_private_broadcast.NodeConfirmedReception(pfrom.GetId());
-                            LogDebug(BCLog::PRIVBROADCAST, "Got a PONG (the transaction will probably reach the network), marking for disconnect, %s",
-                                     pfrom.LogPeer());
-                            pfrom.fDisconnect = true;
-                        }
-                    } else {
-                        // This should never happen
-                        sProblem = "Timing mishap";
-                    }
-                } else {
-                    // Nonce mismatches are normal when pings are overlapping
-                    sProblem = "Nonce mismatch";
-                    if (nonce == 0) {
-                        // This is most likely a bug in another implementation somewhere; cancel this ping
-                        bPingFinished = true;
-                        sProblem = "Nonce zero";
-                    }
-                }
-            } else {
-                sProblem = "Unsolicited pong without ping";
-            }
-        } else {
-            // This is most likely a bug in another implementation somewhere; cancel this ping
-            bPingFinished = true;
-            sProblem = "Short payload";
-        }
-
-        if (!(sProblem.empty())) {
-            LogDebug(BCLog::NET, "pong peer=%d: %s, %x expected, %x received, %u bytes\n",
-                pfrom.GetId(),
-                sProblem,
-                peer.m_ping_nonce_sent,
-                nonce,
-                nAvail);
-        }
-        if (bPingFinished) {
-            peer.m_ping_nonce_sent = 0;
-        }
+        ProcessPong(pfrom, peer, /*ping_end=*/time_received, vRecv);
         return;
     }
 
@@ -5608,6 +5554,66 @@ bool PeerManagerImpl::RejectIncomingTxs(const CNode& peer) const
     return false;
 }
 
+void PeerManagerImpl::ProcessPong(CNode& pfrom, Peer& peer, const NodeClock::time_point ping_end, DataStream& vRecv)
+{
+    uint64_t nonce = 0;
+    const size_t nAvail{vRecv.size()};
+    bool bPingFinished = false;
+    std::string sProblem;
+
+    if (nAvail >= sizeof(nonce)) {
+        vRecv >> nonce;
+
+        // Only process pong message if there is an outstanding ping (old ping without nonce should never pong)
+        if (peer.m_ping_nonce_sent != 0) {
+            if (nonce == peer.m_ping_nonce_sent) {
+                // Matching pong received, this ping is no longer outstanding
+                bPingFinished = true;
+                const auto ping_time = ping_end - peer.m_ping_start.load();
+                if (ping_time.count() >= 0) {
+                    // Let connman know about this successful ping-pong
+                    pfrom.PongReceived(ping_time);
+                    if (pfrom.IsPrivateBroadcastConn()) {
+                        m_tx_for_private_broadcast.NodeConfirmedReception(pfrom.GetId());
+                        LogDebug(BCLog::PRIVBROADCAST, "Got a PONG (the transaction will probably reach the network), marking for disconnect, %s",
+                                 pfrom.LogPeer());
+                        pfrom.fDisconnect = true;
+                    }
+                } else {
+                    // This should never happen
+                    sProblem = "Timing mishap";
+                }
+            } else {
+                // Nonce mismatches are normal when pings are overlapping
+                sProblem = "Nonce mismatch";
+                if (nonce == 0) {
+                    // This is most likely a bug in another implementation somewhere; cancel this ping
+                    bPingFinished = true;
+                    sProblem = "Nonce zero";
+                }
+            }
+        } else {
+            sProblem = "Unsolicited pong without ping";
+        }
+    } else {
+        // This is most likely a bug in another implementation somewhere; cancel this ping
+        bPingFinished = true;
+        sProblem = "Short payload";
+    }
+
+    if (!(sProblem.empty())) {
+        LogDebug(BCLog::NET, "pong peer=%d: %s, %x expected, %x received, %u bytes\n",
+                 pfrom.GetId(),
+                 sProblem,
+                 peer.m_ping_nonce_sent,
+                 nonce,
+                 nAvail);
+    }
+    if (bPingFinished) {
+        peer.m_ping_nonce_sent = 0;
+    }
+}
+
 bool PeerManagerImpl::SetupAddressRelay(const CNode& node, Peer& peer)
 {
     // We don't participate in addr relay with outbound block-relay-only

src/streams.h

@@ -188,7 +188,6 @@ public:
         return std::string{UCharCast(data()), UCharCast(data() + size())};
     }
 
-
     //
     // Vector subset
     //
@@ -209,8 +208,6 @@ public:
     //
     // Stream subset
     //
-    int in_avail() const         { return size(); }
-
     void read(std::span<value_type> dst)
     {
         if (dst.size() == 0) return;