diff --git a/src/main.cpp b/src/main.cpp index be4d4872089..a5eac010ccf 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -2213,9 +2213,17 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv) return error("message inv size() = %d", vInv.size()); } + // find last block in inv vector + unsigned int nLastBlock = (unsigned int)(-1); + for (unsigned int nInv = 0; nInv < vInv.size(); nInv++) { + if (vInv[vInv.size() - 1 - nInv].type == MSG_BLOCK) + nLastBlock = vInv.size() - 1 - nInv; + } CTxDB txdb("r"); - BOOST_FOREACH(const CInv& inv, vInv) + for (int nInv = 0; nInv < vInv.size(); nInv++) { + const CInv &inv = vInv[nInv]; + if (fShutdown) return true; pfrom->AddInventoryKnown(inv); @@ -2224,6 +2232,15 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv) if (fDebug) printf(" got inventory: %s %s\n", inv.ToString().c_str(), fAlreadyHave ? "have" : "new"); + // Always request the last block in an inv bundle (even if we already have it), as it is the + // trigger for the other side to send further invs. If we are stuck on a (very long) side chain, + // this is necessary to connect earlier received orphan blocks to the chain again. + if (fAlreadyHave && nInv == nLastBlock) { + // bypass mapAskFor, and send request directly; it must go through. + std::vector vGetData(1,inv); + pfrom->PushMessage("getdata", vGetData); + } + if (!fAlreadyHave) pfrom->AskFor(inv); else if (inv.type == MSG_BLOCK && mapOrphanBlocks.count(inv.hash))