Merge bitcoin#16688: log: Add validation interface logging

f9abf4a Add logging for CValidationInterface events (Jeffrey Czyz)
6edebac Refactor FormatStateMessage for clarity (Jeffrey Czyz)
72f3227 Format CValidationState properly in all cases (Jeffrey Czyz)
428ac70 Add VALIDATION to BCLog::LogFlags (Jeffrey Czyz)

Pull request description:

  Add logging of `CValidationInterface` callbacks using a new `VALIDATIONINTERFACE` log flag (see bitcoin#12994). A separate flag is desirable as the logging can be noisy and thus may need to be disabled without affecting other logging.

  This could help debug issues where there may be race conditions at play, such as bitcoin#12978.

ACKs for top commit:
  jnewbery:
    ACK f9abf4a
  hebasto:
    ACK f9abf4a
  ariard:
    ACK f9abf4a, only changes since 0cadb12 are replacing log indication `VALIDATIONINTERFACE` by `VALIDATION` and avoiding a forward declaration with a new include
  ryanofsky:
    Code review ACK f9abf4a. Just suggested changes since last review (thanks!)

Tree-SHA512: 3e0f6e2c8951cf46fbad3ff440971d95d526df2a52a2e4d6452a82785c63d53accfdabae66b0b30e2fe0b00737f8d5cb717edbad1460b63acb11a72c8f5d4236

Author: laanwj

src/logging.cpp

@@ -162,6 +162,7 @@ const CLogCategoryDesc LogCategories[] =
     {BCLog::COINDB, "coindb"},
     {BCLog::QT, "qt"},
     {BCLog::LEVELDB, "leveldb"},
+    {BCLog::VALIDATION, "validation"},
     // SYSCOIN
     {BCLog::MN, "masternode"},
     {BCLog::GOBJECT, "gobject"},

src/logging.h

@@ -54,6 +54,7 @@ namespace BCLog {
         COINDB      = (1 << 18),
         QT          = (1 << 19),
         LEVELDB     = (1 << 20),
+        VALIDATION  = (1 << 21),
         // SYSCOIN
         MN  = (1 << 22),
         GOBJECT  = (1 << 23),

src/util/validation.cpp

@@ -8,12 +8,18 @@
 #include <consensus/validation.h>
 #include <tinyformat.h>
 
-/** Convert ValidationState to a human-readable message for logging */
 std::string FormatStateMessage(const ValidationState &state)
 {
-    return strprintf("%s%s",
-        state.GetRejectReason(),
-        state.GetDebugMessage().empty() ? "" : ", "+state.GetDebugMessage());
+    if (state.IsValid()) {
+        return "Valid";
+    }
+
+    const std::string debug_message = state.GetDebugMessage();
+    if (!debug_message.empty()) {
+        return strprintf("%s, %s", state.GetRejectReason(), debug_message);
+    }
+
+    return state.GetRejectReason();
 }
 
 const std::string strMessageMagic = "Bitcoin Signed Message:\n";

src/validationinterface.cpp

@@ -5,8 +5,13 @@
 
 #include <validationinterface.h>
 
+#include <chain.h>
+#include <consensus/validation.h>
+#include <logging.h>
 #include <primitives/block.h>
+#include <primitives/transaction.h>
 #include <scheduler.h>
+#include <util/validation.h>
 
 #include <future>
 #include <unordered_map>
@@ -121,53 +126,90 @@ void SyncWithValidationInterfaceQueue() {
     promise.get_future().wait();
 }
 
+// Use a macro instead of a function for conditional logging to prevent
+// evaluating arguments when logging is not enabled.
+//
+// NOTE: The lambda captures all local variables by value.
+#define ENQUEUE_AND_LOG_EVENT(event, fmt, name, ...)           \
+    do {                                                       \
+        auto local_name = (name);                              \
+        LOG_EVENT("Enqueuing " fmt, local_name, __VA_ARGS__);  \
+        m_internals->m_schedulerClient.AddToProcessQueue([=] { \
+            LOG_EVENT(fmt, local_name, __VA_ARGS__);           \
+            event();                                           \
+        });                                                    \
+    } while (0)
+
+#define LOG_EVENT(fmt, ...) \
+    LogPrint(BCLog::VALIDATION, fmt "\n", __VA_ARGS__)
 
 void CMainSignals::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {
     // Dependencies exist that require UpdatedBlockTip events to be delivered in the order in which
     // the chain actually updates. One way to ensure this is for the caller to invoke this signal
     // in the same critical section where the chain is updated
 
-    m_internals->m_schedulerClient.AddToProcessQueue([pindexNew, pindexFork, fInitialDownload, this] {
+    auto event = [pindexNew, pindexFork, fInitialDownload, this] {
         m_internals->UpdatedBlockTip(pindexNew, pindexFork, fInitialDownload);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: new block hash=%s fork block hash=%s (in IBD=%s)", __func__,
+                          pindexNew->GetBlockHash().ToString(),
+                          pindexFork ? pindexFork->GetBlockHash().ToString() : "null",
+                          fInitialDownload);
 }
 
 void CMainSignals::TransactionAddedToMempool(const CTransactionRef &ptx) {
-    m_internals->m_schedulerClient.AddToProcessQueue([ptx, this] {
+    auto event = [ptx, this] {
         m_internals->TransactionAddedToMempool(ptx);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: txid=%s wtxid=%s", __func__,
+                          ptx->GetHash().ToString(),
+                          ptx->GetWitnessHash().ToString());
 }
 
 void CMainSignals::TransactionRemovedFromMempool(const CTransactionRef &ptx) {
-    m_internals->m_schedulerClient.AddToProcessQueue([ptx, this] {
+    auto event = [ptx, this] {
         m_internals->TransactionRemovedFromMempool(ptx);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: txid=%s wtxid=%s", __func__,
+                          ptx->GetHash().ToString(),
+                          ptx->GetWitnessHash().ToString());
 }
 
 void CMainSignals::BlockConnected(const std::shared_ptr<const CBlock> &pblock, const CBlockIndex *pindex, const std::shared_ptr<const std::vector<CTransactionRef>>& pvtxConflicted) {
-    m_internals->m_schedulerClient.AddToProcessQueue([pblock, pindex, pvtxConflicted, this] {
+    auto event = [pblock, pindex, pvtxConflicted, this] {
         m_internals->BlockConnected(pblock, pindex, *pvtxConflicted);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: block hash=%s block height=%d", __func__,
+                          pblock->GetHash().ToString(),
+                          pindex->nHeight);
 }
 
 void CMainSignals::BlockDisconnected(const std::shared_ptr<const CBlock>& pblock, const CBlockIndex* pindex)
 {
-    m_internals->m_schedulerClient.AddToProcessQueue([pblock, pindex, this] {
+    auto event = [pblock, pindex, this] {
         m_internals->BlockDisconnected(pblock, pindex);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: block hash=%s block height=%d", __func__,
+                          pblock->GetHash().ToString(),
+                          pindex->nHeight);
 }
 
 void CMainSignals::ChainStateFlushed(const CBlockLocator &locator) {
-    m_internals->m_schedulerClient.AddToProcessQueue([locator, this] {
+    auto event = [locator, this] {
         m_internals->ChainStateFlushed(locator);
-    });
+    };
+    ENQUEUE_AND_LOG_EVENT(event, "%s: block hash=%s", __func__,
+                          locator.IsNull() ? "null" : locator.vHave.front().ToString());
 }
 
 void CMainSignals::BlockChecked(const CBlock& block, const BlockValidationState& state) {
+    LOG_EVENT("%s: block hash=%s state=%s", __func__,
+              block.GetHash().ToString(), FormatStateMessage(state));
     m_internals->BlockChecked(block, state);
 }
 
 void CMainSignals::NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock> &block) {
+    LOG_EVENT("%s: block hash=%s", __func__, block->GetHash().ToString());
     m_internals->NewPoWValidBlock(pindex, block);
 }
 // SYSCOIN

test/lint/lint-format-strings.py

@@ -17,6 +17,7 @@
     ("src/index/base.cpp", "FatalError(const char* fmt, const Args&... args)"),
     ("src/netbase.cpp", "LogConnectFailure(bool manual_connection, const char* fmt, const Args&... args)"),
     ("src/util/system.cpp", "strprintf(_(COPYRIGHT_HOLDERS).translated, COPYRIGHT_HOLDERS_SUBSTITUTION)"),
+    ("src/validationinterface.cpp", "LogPrint(BCLog::VALIDATION, fmt \"\\n\", __VA_ARGS__)"),
     ("src/wallet/wallet.h",  "WalletLogPrintf(std::string fmt, Params... parameters)"),
     ("src/wallet/wallet.h", "LogPrintf((\"%s \" + fmt).c_str(), GetDisplayName(), parameters...)"),
     ("src/logging.h", "LogPrintf(const char* fmt, const Args&... args)"),