log: demote the four lines that were 90% of debug.log behind /debugrelay

A 13-hour production capture was ~71% "sending: tx", ~16% "Nostr:
discovered .btf peer", ~5% "Relaying wtx", and ~43% of raw lines were
CBlock/CTransaction dumps -- all already under -debug, which operators
run permanently, so -debug was useless as a filter.

The category mechanism gains a verbose tier: "relay" and
"nostrdiscovery" are accepted only with the new /debugrelay flag (which
implies /debug); everything else keeps its current gate. Demoted, with
message text unchanged for anyone grepping it:

  net.h     "sending: tx (N bytes)" (BeginMessage/EndMessage/
            AbortMessage all pick the category from the command, so no
            orphaned "(N bytes)" fragments leak into a plain -debug log)
  main.cpp  "Relaying wtx", "received block:" + CBlock::print, and the
            BitcoinMiner block dump
  nostr.cpp "Nostr: discovered .btf peer" -> "nostrdiscovery"

Pool/worker/payout, [payout], BLOCK ORPHANED/ACCEPTED and share flow
lines are untouched. Because LogPrint dedup keys on category, demoted
lines also keep their burst collapse under /debugrelay.

Closes #35

6 files changed, 51 insertions, 8 deletions

diff --git a/src/main.cpp b/src/main.cpp
index 7b3e555..80f5f31 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1712,7 +1712,7 @@ void CWalletTx::RelayWalletTransaction(CTxDB& txdb)
         uint256 hash = GetHash();
         if (!txdb.ContainsTx(hash))
         {
-            if (LogAcceptsCategory("net")) printf("Relaying wtx %s\n", hash.ToString().substr(0,6).c_str());
+            if (LogAcceptsCategory("relay")) printf("Relaying wtx %s\n", hash.ToString().substr(0,6).c_str());
             RelayMessage(CInv(MSG_TX, hash), (CTransaction)*this);
         }
     }
@@ -3263,7 +3263,7 @@ bool ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         vRecv >> *pblock;
 
         //// debug print
-        if (LogAcceptsCategory("net")) { printf("received block:\n"); pblock->print(); }
+        if (LogAcceptsCategory("relay")) { printf("received block:\n"); pblock->print(); }
 
         CInv inv(MSG_BLOCK, pblock->GetHash());
         pfrom->AddInventoryKnown(inv);
@@ -4555,7 +4555,7 @@ bool BitcoinMiner(int nThreadId)
                     //// debug print
                     if (LogAcceptsCategory("net")) printf("BitcoinMiner:\n");
                     if (LogAcceptsCategory("net")) printf("RandomX proof-of-work found  \n  powhash: %s  \ntarget: %s\n", hash.GetHex().c_str(), hashTarget.GetHex().c_str());
-                    if (LogAcceptsCategory("net")) pblock->print();
+                    if (LogAcceptsCategory("relay")) pblock->print();
 
                 SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_NORMAL);
                 CRITICAL_BLOCK(cs_main)
diff --git a/src/main_gui.cpp b/src/main_gui.cpp
index 05f5ecf..163d78e 100644
--- a/src/main_gui.cpp
+++ b/src/main_gui.cpp
@@ -111,6 +111,7 @@ static void PrintUsage()
     printf("  /help, -help, --help, /?\n");
     printf("  /datadir=PATH\n");
     printf("  /debug\n");
+    printf("  /debugrelay                (/debug plus per-message relay chatter and block dumps)\n");
     printf("  /maxdebugfilesize=N        (roll debug.log at N MB, default 1024; 0 = never)\n");
     printf("  /gen\n");
     printf("  /nogui or /daemon\n");
@@ -192,6 +193,17 @@ static void ParseStartupArguments(int argc, char* argv[])
     if (arg(argc,argv,"/debug") || arg(argc,argv,"-debug"))
         fDebug = true;
 
+    // /debugrelay -- everything /debug shows, plus the per-message firehose
+    // ("relay" and "nostrdiscovery" categories: sending: tx, Relaying wtx,
+    // raw CBlock dumps, per-peer discovery lines). That traffic was ~90% of
+    // a 13-hour production debug.log (issue #35), so plain /debug leaves it
+    // off; the message text itself is unchanged for anyone grepping it.
+    if (arg(argc,argv,"/debugrelay") || arg(argc,argv,"-debugrelay"))
+    {
+        fDebug = true;
+        fDebugRelay = true;
+    }
+
     // /maxdebugfilesize=N -- roll debug.log to debug.log.old once it passes
     // N MB, checked on each write. Default is 1024 (see util.cpp); 0 turns
     // the check off and leaves rotation entirely to logrotate.
diff --git a/src/net.h b/src/net.h
index 9f3c7e4..1aee973 100644
--- a/src/net.h
+++ b/src/net.h
@@ -802,6 +802,18 @@ public:
 
 
 
+    // "sending: tx (N bytes)" alone was ~71% of a 13-hour production
+    // debug.log (issue #35), so tx sends are demoted to the /debugrelay-gated
+    // "relay" category; every other command's send trace stays on "net".
+    // The line is emitted in pieces across BeginMessage/EndMessage/
+    // AbortMessage, so all three must agree on the category or orphaned
+    // "(N bytes)" fragments would leak into a plain -debug log.
+    // Valid only mid-message (nPushPos != -1).
+    const char* SendLogCategory() const
+    {
+        return strcmp(GetMessageCommand(), "tx") == 0 ? "relay" : "net";
+    }
+
     void BeginMessage(const char* pszCommand)
     {
         EnterCriticalSection(&cs_vSend);
@@ -809,17 +821,19 @@ public:
             AbortMessage();
         nPushPos = vSend.size();
         vSend << CMessageHeader(pszCommand, 0);
-        if (LogAcceptsCategory("net")) printf("sending: %-12s ", pszCommand);
+        if (LogAcceptsCategory(SendLogCategory())) printf("sending: %-12s ", pszCommand);
     }
 
     void AbortMessage()
     {
         if (nPushPos == -1)
             return;
+        // Capture before nPushPos is cleared; GetMessageCommand() needs it.
+        const char* pszCategory = SendLogCategory();
         vSend.resize(nPushPos);
         nPushPos = -1;
         LeaveCriticalSection(&cs_vSend);
-        if (LogAcceptsCategory("net")) printf("(aborted)\n");
+        if (LogAcceptsCategory(pszCategory)) printf("(aborted)\n");
     }
 
     void EndMessage()
@@ -839,10 +853,10 @@ public:
         unsigned int nSize = vSend.size() - nPushPos - sizeof(CMessageHeader);
         memcpy((char*)&vSend[nPushPos] + offsetof(CMessageHeader, nMessageSize), &nSize, sizeof(nSize));
 
-        if (LogAcceptsCategory("net")) printf("(%d bytes)  ", nSize);
+        if (LogAcceptsCategory(SendLogCategory())) printf("(%d bytes)  ", nSize);
         //for (int i = nPushPos+sizeof(CMessageHeader); i < min(vSend.size(), nPushPos+sizeof(CMessageHeader)+20U); i++)
         //    printf("%02x ", vSend[i] & 0xff);
-        if (LogAcceptsCategory("net")) printf("\n");
+        if (LogAcceptsCategory(SendLogCategory())) printf("\n");
 
         nPushPos = -1;
         LeaveCriticalSection(&cs_vSend);
diff --git a/src/nostr.cpp b/src/nostr.cpp
index e2d839c..9bbf74e 100644
--- a/src/nostr.cpp
+++ b/src/nostr.cpp
@@ -1440,7 +1440,7 @@ static bool SeedFromRelay(CNostrKey& key, const string& relay)
                         else if (createdAt > it->second)  it->second = createdAt; // refresh
                     }
                     if (fNew && fDebug)
-                        LogPrint("nostr", "Nostr: discovered .btf peer %s\n", peerAddr.c_str());
+                        LogPrint("nostrdiscovery", "Nostr: discovered .btf peer %s\n", peerAddr.c_str());
                     if (++nPeers > 500) break;
                 }
                 else if (type == "EOSE")
diff --git a/src/util.cpp b/src/util.cpp
index 52cda84..a5a4e80 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -7,6 +7,7 @@
 
 
 bool fDebug = false;
+bool fDebugRelay = false;
 
 // In-process cap for debug.log, in bytes. Default matches the 1G trigger of
 // the shipped logrotate policy so a long-running node stays bounded even
@@ -31,10 +32,22 @@ static bool LogCategoryDefaultOn(const char* category)
            strcmp(category, "payout") == 0;
 }
 
+// Categories so noisy they drown out everything else even under -debug:
+// per-message send traces, wallet relay rebroadcasts, raw CBlock dumps and
+// per-address discovery lines made up ~90% of a 13-hour production capture
+// (issue #35). They need /debugrelay, not merely /debug.
+static bool LogCategoryVerboseOnly(const char* category)
+{
+    return strcmp(category, "relay")          == 0 ||
+           strcmp(category, "nostrdiscovery") == 0;
+}
+
 bool LogAcceptsCategory(const char* category)
 {
     if (LogCategoryDefaultOn(category))
         return true;
+    if (LogCategoryVerboseOnly(category))
+        return fDebugRelay;
     return fDebug;
 }
 
diff --git a/src/util.h b/src/util.h
index f2ea23f..c47b8a7 100644
--- a/src/util.h
+++ b/src/util.h
@@ -87,6 +87,10 @@ inline T& REF(const T& val)
 
 extern bool fDebug;
 
+// /debugrelay: the per-message firehose ("relay" and "nostrdiscovery"
+// categories) that even -debug keeps off. See LogAcceptsCategory().
+extern bool fDebugRelay;
+
 // debug.log is rolled to debug.log.old once it grows past this many bytes
 // (set from -maxdebugfilesize, in MB; 0 disables the check). See the roll
 // site in OutputDebugStringF() below.