Backport Bitcoin PR#9183: Final Preparation for main.cpp Split (#1561)

* Expose AcceptBlockHeader through main.h * Split ::HEADERS processing into two separate cs_main locks This will allow NotifyHeaderTip to be called from an AcceptBlockHeader wrapper function without holding cs_main. * Use exposed ProcessNewBlockHeaders from ProcessMessages
dashpay · Aug 2, 2017 · 415085c · 415085c
1 parent b4b3431
commit 415085c
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Showing 2 changed files with 46 additions and 16 deletions.
diff --git a/src/main.cpp b/src/main.cpp
@@ -3835,7 +3835,7 @@ bool ContextualCheckBlock(const CBlock& block, CValidationState& state, CBlockIn
     return true;
 }
 
-static bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex=NULL)
+static bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex)
 {
     AssertLockHeld(cs_main);
     // Check for duplicate
@@ -3886,6 +3886,21 @@ static bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state
     return true;
 }
 
+// Exposed wrapper for AcceptBlockHeader
+bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex)
+{
+    {
+        LOCK(cs_main);
+        for (const CBlockHeader& header : headers) {
+            if (!AcceptBlockHeader(header, state, chainparams, ppindex)) {
+                return false;
+            }
+        }
+    }
+    NotifyHeaderTip();
+    return true;
+}
+
 /** Store block on disk. If dbp is non-NULL, the file is known to already reside on disk */
 static bool AcceptBlock(const CBlock& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const CDiskBlockPos* dbp, bool* fNewBlock)
 {
@@ -6020,32 +6035,38 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
             ReadCompactSize(vRecv); // ignore tx count; assume it is 0.
         }
 
-        {
-        LOCK(cs_main);
-
         if (nCount == 0) {
             // Nothing interesting. Stop asking this peers for more headers.
             return true;
         }
 
         CBlockIndex *pindexLast = NULL;
-        BOOST_FOREACH(const CBlockHeader& header, headers) {
-            CValidationState state;
-            if (pindexLast != NULL && header.hashPrevBlock != pindexLast->GetBlockHash()) {
+        {
+        LOCK(cs_main);
+        uint256 hashLastBlock;
+        for (const CBlockHeader& header : headers) {
+            if (!hashLastBlock.IsNull() && header.hashPrevBlock != hashLastBlock) {
                 Misbehaving(pfrom->GetId(), 20);
                 return error("non-continuous headers sequence");
             }
-            if (!AcceptBlockHeader(header, state, chainparams, &pindexLast)) {
-                int nDoS;
-                if (state.IsInvalid(nDoS)) {
-                    if (nDoS > 0)
-                        Misbehaving(pfrom->GetId(), nDoS);
-                    std::string strError = "invalid header received " + header.GetHash().ToString();
-                    return error(strError.c_str());
+            hashLastBlock = header.GetHash();
+        }
+        }
+
+        CValidationState state;
+        if (!ProcessNewBlockHeaders(headers, state, chainparams, &pindexLast)) {
+            int nDoS;
+            if (state.IsInvalid(nDoS)) {
+                if (nDoS > 0) {
+                    LOCK(cs_main);
+                    Misbehaving(pfrom->GetId(), nDoS);
                 }
+                return error("invalid header received");
             }
         }
 
+        {
+        LOCK(cs_main);
         if (pindexLast)
             UpdateBlockAvailability(pfrom->GetId(), pindexLast->GetBlockHash());
 
@@ -6104,8 +6125,6 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
             }
         }
         }
-
-        NotifyHeaderTip();
     }
 
     else if (strCommand == NetMsgType::BLOCK && !fImporting && !fReindex) // Ignore blocks received while importing

diff --git a/src/main.h b/src/main.h
@@ -208,6 +208,17 @@ static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024;
  * @return True if state.IsValid()
  */
 bool ProcessNewBlock(const CChainParams& chainparams, const CBlock* pblock, bool fForceProcessing, const CDiskBlockPos* dbp, bool* fNewBlock);
+
+/**
+ * Process incoming block headers.
+ *
+ * @param[in]  block The block headers themselves
+ * @param[out] state This may be set to an Error state if any error occurred processing them
+ * @param[in]  chainparams The params for the chain we want to connect to
+ * @param[out] ppindex If set, the pointer will be set to point to the last new block index object for the given headers
+ */
+bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex=NULL);
+
 /** Check whether enough disk space is available for an incoming block */
 bool CheckDiskSpace(uint64_t nAdditionalBytes = 0);
 /** Open a block file (blk?????.dat) */