比特幣源碼分析-boost::signal的使用

bitcoin 代碼中大量使用 boost::signal, boost::signal 實(shí)現(xiàn)了信號(hào)與槽的事件通知機(jī)制倔约，或者說(shuō)是一種消息的發(fā)布與訂閱機(jī)制蟋定， signal 類型是一個(gè)可調(diào)用類型已球，slot 就是callback 對(duì)象，或者說(shuō)事件的訂閱者谤狡，signal 實(shí)例是一個(gè)可調(diào)用對(duì)象并蝗，調(diào)用signal 對(duì)象，就相當(dāng)于發(fā)布了相應(yīng)的事件, signal 的connect切蟋， disconnect 方法分別相當(dāng)于對(duì)事件的訂閱统捶，取消。

#include <boost/signals2.hpp>
#include <iostream>

void print_args(float x, float y)
{
      std::cout << "The arguments are " << x << " and " << y << std::endl;
}

void print_sum(float x, float y)
{
      std::cout << "The sum is " << x + y << std::endl;
}

void print_product(float x, float y)
{
      std::cout << "The product is " << x * y << std::endl;
}

void print_difference(float x, float y)
{
      std::cout << "The difference is " << x - y << std::endl;
}

void print_quotient(float x, float y)
{
      std::cout << "The quotient is " << x / y << std::endl;
}

int main() {
    boost::signals2::signal<void(float, float)> sig;

    sig.connect(print_args);
    sig.connect(print_sum);
    sig.connect(print_product);
    sig.connect(print_difference);
    sig.connect(print_quotient);

    sig(5., 3.);
    return 0;

上面這個(gè)例子, 有五個(gè)函數(shù)訂閱sig 事件柄粹，sig(5. , 3.) 的調(diào)用觸發(fā)事件喘鸟，參數(shù)5，3驻右，相當(dāng)于事件攜帶的消息paylaod, 傳給了五個(gè)事件訂閱者什黑。

bitcoin 中定義了類型CMainSignals 來(lái)統(tǒng)一管理各個(gè)功能模塊的事件通知，CMainSignal 是一個(gè)資源管理類型堪夭，主要工作代理給由unique_ptr 管理內(nèi)存的成員 m_internals , 它的類型是MainSignalsInstance愕把，內(nèi)部定義十個(gè)boost signal 變量，分別表達(dá)十種要通知的事件森爽。

class CMainSignals {
private:
    std::unique_ptr<MainSignalsInstance> m_internals;

    friend void ::RegisterValidationInterface(CValidationInterface*);
    friend void ::UnregisterValidationInterface(CValidationInterface*);
    friend void ::UnregisterAllValidationInterfaces();
    friend void ::CallFunctionInValidationInterfaceQueue(std::function<void ()> func);

    void MempoolEntryRemoved(CTransactionRef tx, MemPoolRemovalReason reason);

public:
    /** Register a CScheduler to give callbacks which should run in the background (may only be called once) */
    void RegisterBackgroundSignalScheduler(CScheduler& scheduler);
    /** Unregister a CScheduler to give callbacks which should run in the background - these callbacks will now be dropped! */
    void UnregisterBackgroundSignalScheduler();
    /** Call any remaining callbacks on the calling thread */
    void FlushBackgroundCallbacks();

    size_t CallbacksPending();

    /** Register with mempool to call TransactionRemovedFromMempool callbacks */
    void RegisterWithMempoolSignals(CTxMemPool& pool);
    /** Unregister with mempool */
    void UnregisterWithMempoolSignals(CTxMemPool& pool);

    void UpdatedBlockTip(const CBlockIndex *, const CBlockIndex *, bool fInitialDownload);
    void TransactionAddedToMempool(const CTransactionRef &);
    void BlockConnected(const std::shared_ptr<const CBlock> &, const CBlockIndex *pindex, const std::shared_ptr<const std::vector<CTransactionRef>> &);
    void BlockDisconnected(const std::shared_ptr<const CBlock> &);
    void SetBestChain(const CBlockLocator &);
    void Inventory(const uint256 &);
    void Broadcast(int64_t nBestBlockTime, CConnman* connman);
    void BlockChecked(const CBlock&, const CValidationState&);
    void NewPoWValidBlock(const CBlockIndex *, const std::shared_ptr<const CBlock>&);
};

struct MainSignalsInstance {
    boost::signals2::signal<void (const CBlockIndex *, const CBlockIndex *, bool fInitialDownload)> UpdatedBlockTip;
    boost::signals2::signal<void (const CTransactionRef &)> TransactionAddedToMempool;
    boost::signals2::signal<void (const std::shared_ptr<const CBlock> &, const CBlockIndex *pindex, const std::vector<CTransactionRef>&)> BlockConnected;
    boost::signals2::signal<void (const std::shared_ptr<const CBlock> &)> BlockDisconnected;
    boost::signals2::signal<void (const CTransactionRef &)> TransactionRemovedFromMempool;
    boost::signals2::signal<void (const CBlockLocator &)> SetBestChain;
    boost::signals2::signal<void (const uint256 &)> Inventory;
    boost::signals2::signal<void (int64_t nBestBlockTime, CConnman* connman)> Broadcast;
    boost::signals2::signal<void (const CBlock&, const CValidationState&)> BlockChecked;
    boost::signals2::signal<void (const CBlockIndex *, const std::shared_ptr<const CBlock>&)> NewPoWValidBlock;

    // We are not allowed to assume the scheduler only runs in one thread,
    // but must ensure all callbacks happen in-order, so we end up creating
    // our own queue here :(
    SingleThreadedSchedulerClient m_schedulerClient;

    explicit MainSignalsInstance(CScheduler *pscheduler) : m_schedulerClient(pscheduler) {}
};

類型CValidationInterface 主要是統(tǒng)一表示某些對(duì)MainSignalsInstance 中定義的十個(gè)事件感興趣的對(duì)象恨豁，即這些事件的訂閱者，所有對(duì)這些事件感興趣代碼繼承CValidationInterface類型爬迟，
提供自己版本的這些虛成員函數(shù)的實(shí)現(xiàn)橘蜜，覆蓋baseCValidationInterface 中對(duì)應(yīng)的空方法，表達(dá)對(duì)相應(yīng)的事件感興趣付呕，不感興趣的事件的回調(diào)方法繼續(xù)是那些繼承自base class 的空方法计福。

class CValidationInterface {
protected:
    
    virtual void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {}
    
    virtual void TransactionAddedToMempool(const CTransactionRef &ptxn) {}
   
    virtual void TransactionRemovedFromMempool(const CTransactionRef &ptx) {}
    
    virtual void BlockConnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex *pindex, const std::vector<CTransactionRef> &txnConflicted) {}
    
    virtual void BlockDisconnected(const std::shared_ptr<const CBlock> &block) {}
    
    virtual void SetBestChain(const CBlockLocator &locator) {}
   
    virtual void Inventory(const uint256 &hash) {}

    virtual void ResendWalletTransactions(int64_t nBestBlockTime, CConnman* connman) {}
    
    virtual void BlockChecked(const CBlock&, const CValidationState&) {}
    
    virtual void NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& block) {};
    friend void ::RegisterValidationInterface(CValidationInterface*);
    friend void ::UnregisterValidationInterface(CValidationInterface*);
    friend void ::UnregisterAllValidationInterfaces();
};

CValidationInterface 有四個(gè)子類， CWallet , CZMQNotificationInterface, submitblock_StateCatcher, PeerLogicValidation 分別對(duì)應(yīng)四個(gè)對(duì)MainSignalsInstance 中的事件感興趣的訂閱者徽职。

class CWallet final : public CCryptoKeyStore, public CValidationInterface
{
       ...............
           void TransactionAddedToMempool(const CTransactionRef& tx) override;
           void BlockConnected(const std::shared_ptr<const CBlock>& pblock, const CBlockIndex *pindex, const std::vector<CTransactionRef>& vtxConflicted) override;
           void BlockDisconnected(const std::shared_ptr<const CBlock>& pblock) override;
           void TransactionRemovedFromMempool(const CTransactionRef &ptx) override;
           void ResendWalletTransactions(int64_t nBestBlockTime, CConnman* connman) override;
           void SetBestChain(const CBlockLocator& loc) override;
           void Inventory(const uint256 &hash) override
          {
              {
                  LOCK(cs_wallet);
                 std::map<uint256, int>::iterator mi = mapRequestCount.find(hash);
                 if (mi != mapRequestCount.end())
                             (*mi).second++;
              }
          }
       ...............
};

class CZMQNotificationInterface final : public CValidationInterface
{
     ................
    // CValidationInterface
    void TransactionAddedToMempool(const CTransactionRef& tx) override;
    void BlockConnected(const std::shared_ptr<const CBlock>& pblock, const CBlockIndex* pindexConnected, const std::vector<CTransactionRef>& vtxConflicted) override;
    void BlockDisconnected(const std::shared_ptr<const CBlock>& pblock) override;
    void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) override;
    .................
};
class submitblock_StateCatcher : public CValidationInterface
{
public:
    uint256 hash;
    bool found;
    CValidationState state;

    explicit submitblock_StateCatcher(const uint256 &hashIn) : hash(hashIn), found(false), state() {}

protected:
    void BlockChecked(const CBlock& block, const CValidationState& stateIn) override {
        if (block.GetHash() != hash)
            return;
        found = true;
        state = stateIn;
    }
};

class PeerLogicValidation : public CValidationInterface, public NetEventsInterface 
{
private:
    CConnman* const connman;

public:
    explicit PeerLogicValidation(CConnman* connman, CScheduler &scheduler);

    void BlockConnected(const std::shared_ptr<const CBlock>& pblock, const CBlockIndex* pindexConnected, const std::vector<CTransactionRef>& vtxConflicted) override;
    void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) override;
    void BlockChecked(const CBlock& block, const CValidationState& state) override;
    void NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& pblock) override;
    ........
};

這四個(gè)訂閱者通過(guò)調(diào)用RegisterValidationInterface象颖， UnregisterValidationInterface 訂閱，取消事件通知姆钉，函數(shù)接受參數(shù)是指向訂閱者的指針说订。

void RegisterValidationInterface(CValidationInterface* pwalletIn) {
    g_signals.m_internals->UpdatedBlockTip.connect(boost::bind(&CValidationInterface::UpdatedBlockTip, pwalletIn, _1, _2, _3));
    g_signals.m_internals->TransactionAddedToMempool.connect(boost::bind(&CValidationInterface::TransactionAddedToMempool, pwalletIn, _1));
    g_signals.m_internals->BlockConnected.connect(boost::bind(&CValidationInterface::BlockConnected, pwalletIn, _1, _2, _3));
    g_signals.m_internals->BlockDisconnected.connect(boost::bind(&CValidationInterface::BlockDisconnected, pwalletIn, _1));
    g_signals.m_internals->TransactionRemovedFromMempool.connect(boost::bind(&CValidationInterface::TransactionRemovedFromMempool, pwalletIn, _1));
    g_signals.m_internals->SetBestChain.connect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
    g_signals.m_internals->Inventory.connect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
    g_signals.m_internals->Broadcast.connect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1, _2));
    g_signals.m_internals->BlockChecked.connect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
    g_signals.m_internals->NewPoWValidBlock.connect(boost::bind(&CValidationInterface::NewPoWValidBlock, pwalletIn, _1, _2));
}

void UnregisterValidationInterface(CValidationInterface* pwalletIn) {
    g_signals.m_internals->BlockChecked.disconnect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
    g_signals.m_internals->Broadcast.disconnect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn, _1, _2));
    g_signals.m_internals->Inventory.disconnect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
    g_signals.m_internals->SetBestChain.disconnect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
    g_signals.m_internals->TransactionAddedToMempool.disconnect(boost::bind(&CValidationInterface::TransactionAddedToMempool, pwalletIn, _1));
    g_signals.m_internals->BlockConnected.disconnect(boost::bind(&CValidationInterface::BlockConnected, pwalletIn, _1, _2, _3));
    g_signals.m_internals->BlockDisconnected.disconnect(boost::bind(&CValidationInterface::BlockDisconnected, pwalletIn, _1));
    g_signals.m_internals->TransactionRemovedFromMempool.disconnect(boost::bind(&CValidationInterface::TransactionRemovedFromMempool, pwalletIn, _1));
    g_signals.m_internals->UpdatedBlockTip.disconnect(boost::bind(&CValidationInterface::UpdatedBlockTip, pwalletIn, _1, _2, _3));
    g_signals.m_internals->NewPoWValidBlock.disconnect(boost::bind(&CValidationInterface::NewPoWValidBlock, pwalletIn, _1, _2));
}

在程序啟動(dòng)，初始化階段育韩，啟動(dòng)調(diào)度器線程

bool AppInitMain()
{
      .................
     CScheduler::Function serviceLoop = boost::bind(&CScheduler::serviceQueue, &scheduler);
     threadGroup.create_thread(boost::bind(&TraceThread<CScheduler::Function>, "scheduler", serviceLoop));
     .................
}

調(diào)用RegisterBackgroundSignalScheduler(), 初始化全局MainSignalsInstance 實(shí)例; 調(diào)用RegisterWithMempoolSignals(), 訂閱全局內(nèi)存池對(duì)象的NotifyEntryRemoved 事件通知, MainSignalsInstance 只對(duì)由于超時(shí)克蚂，大小限制闺鲸， blockchian 重組筋讨，替換等原因發(fā)生的離開內(nèi)存池事件感興趣，收到后MainSignalsInstance 再作為事件發(fā)布者摸恍，轉(zhuǎn)發(fā)給其他訂閱者悉罕，如CWallet赤屋。

bool AppInitMain()
{
     ......
    GetMainSignals().RegisterBackgroundSignalScheduler(scheduler);
    GetMainSignals().RegisterWithMempoolSignals(mempool);
    ........
 }

初始化全局的連接管理對(duì)象connman 后，初始化全局的peerLogic 對(duì)象壁袄，然后調(diào)用RegisterValidationInterface(), peerLogic 成為MainSignalsInstance 對(duì)象的訂閱者, 如果用戶編譯了zeromq支持模塊类早，調(diào)用RegisterValidationInterface(), pzmqNotificationInterface 訂閱MainSignalsInstance 。

bool AppInitMain()
{
    .............
    assert(!g_connman);
    g_connman = std::unique_ptr<CConnman>(new CConnman(GetRand(std::numeric_limits<uint64_t>::max()), GetRand(std::numeric_limits<uint64_t>::max())));
    CConnman& connman = *g_connman;

    peerLogic.reset(new PeerLogicValidation(&connman, scheduler));
    RegisterValidationInterface(peerLogic.get());
    .............
    
#if ENABLE_ZMQ
    pzmqNotificationInterface = CZMQNotificationInterface::Create();

    if (pzmqNotificationInterface) {
        RegisterValidationInterface(pzmqNotificationInterface);
    }
#endif
    ...............
}

如果錢包功能開啟嗜逻，啟動(dòng)后打開錢包過(guò)程涩僻，會(huì)把錢包注冊(cè)成為MainSignalsInstance的訂閱者。

bool AppInitMain()
{
      ........
#ifdef ENABLE_WALLET
    if (!OpenWallets())
        return false;
#else
    LogPrintf("No wallet support compiled in!\n");
#endif

      ........
}

bool OpenWallets()
{
    if (gArgs.GetBoolArg("-disablewallet", DEFAULT_DISABLE_WALLET)) {
        LogPrintf("Wallet disabled!\n");
        return true;
    }

    for (const std::string& walletFile : gArgs.GetArgs("-wallet")) {
        CWallet * const pwallet = CWallet::CreateWalletFromFile(walletFile);
        if (!pwallet) {
            return false;
        }
        vpwallets.push_back(pwallet);
    }

    return true;
}

CWallet* CWallet::CreateWalletFromFile(const std::string walletFile)
{
        ......
            CWallet *walletInstance = new CWallet(std::move(dbw));
            RegisterValidationInterface(walletInstance);
        ......
}

在submitblock rpc調(diào)用中栈顷，用戶提交hex編碼的原始block逆日，解析后，調(diào)用ProcessNewBlock()檢查處理萄凤，使用類型submitblock_StateCatcher 的對(duì)象sc 作為MainSignalsInstance 的訂閱者室抽，
對(duì)提交過(guò)去的block 的驗(yàn)證結(jié)果，作為事件通知返回給rpc 調(diào)用靡努。

UniValue submitblock(const JSONRPCRequest& request)
{
     ...........
     
    submitblock_StateCatcher sc(block.GetHash());
    RegisterValidationInterface(&sc);
    bool fAccepted = ProcessNewBlock(Params(), blockptr, true, nullptr);
    UnregisterValidationInterface(&sc);

     ...........
}

CMainSignals 類型上面定義了一堆觸發(fā)事件的方法, 別的代碼模塊調(diào)用這些方法坪圾，觸發(fā)相應(yīng)的事件，把事件通知發(fā)給相關(guān)的訂閱者惑朦。

void CMainSignals::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {
    m_internals->m_schedulerClient.AddToProcessQueue([pindexNew, pindexFork, fInitialDownload, this] {
        m_internals->UpdatedBlockTip(pindexNew, pindexFork, fInitialDownload);
    });
}

void CMainSignals::TransactionAddedToMempool(const CTransactionRef &ptx) {
    m_internals->m_schedulerClient.AddToProcessQueue([ptx, this] {
        m_internals->TransactionAddedToMempool(ptx);
    });
}

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] {
        m_internals->BlockConnected(pblock, pindex, *pvtxConflicted);
    });
}

void CMainSignals::BlockDisconnected(const std::shared_ptr<const CBlock> &pblock) {
    m_internals->m_schedulerClient.AddToProcessQueue([pblock, this] {
        m_internals->BlockDisconnected(pblock);
    });
}

void CMainSignals::SetBestChain(const CBlockLocator &locator) {
    m_internals->m_schedulerClient.AddToProcessQueue([locator, this] {
        m_internals->SetBestChain(locator);
    });
}

void CMainSignals::Inventory(const uint256 &hash) {
    m_internals->m_schedulerClient.AddToProcessQueue([hash, this] {
        m_internals->Inventory(hash);
    });
}

void CMainSignals::Broadcast(int64_t nBestBlockTime, CConnman* connman) {
    m_internals->Broadcast(nBestBlockTime, connman);
}

void CMainSignals::BlockChecked(const CBlock& block, const CValidationState& state) {
    m_internals->BlockChecked(block, state);
}

void CMainSignals::NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock> &block) {
    m_internals->NewPoWValidBlock(pindex, block);
}

CChainState 的ActivateBestChain方法里兽泄，發(fā)布BlockConnected， UpdatedBlockTip 事件:

bool CChainState::ActivateBestChain(CValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock) {
           ..............................
           for (const PerBlockConnectTrace& trace : connectTrace.GetBlocksConnected()) {
                assert(trace.pblock && trace.pindex);
                GetMainSignals().BlockConnected(trace.pblock, trace.pindex, trace.conflictedTxs);
            }

           ..............................
           GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork, fInitialDownload);
           ...............................
}

CChainState 的AcceptBlock 方法里行嗤，發(fā)布NewPoWValidBlock 事件:

bool CChainState::AcceptBlock(const std::shared_ptr<const CBlock>& pblock, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const CDiskBlockPos* dbp, bool* fNewBlock)
{
        .......................
        
        if (!IsInitialBlockDownload() && chainActive.Tip() == pindex->pprev)
               GetMainSignals().NewPoWValidBlock(pindex, pblock);

        ......................
}

CChainState 的DisconnectTip 方法里已日，發(fā)布 BlockDisconnected 事件:

bool CChainState::DisconnectTip(CValidationState& state, const CChainParams& chainparams, DisconnectedBlockTransactions *disconnectpool)
{
   ...................
     GetMainSignals().BlockDisconnected(pblock);
     ..............
}

CChainState 的ConnectTip 方法里，發(fā)布 BlockChecked 事件:

bool CChainState::ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions &disconnectpool)
{
     ................
     
        CCoinsViewCache view(pcoinsTip.get());
        bool rv = ConnectBlock(blockConnecting, state, pindexNew, view, chainparams);
        GetMainSignals().BlockChecked(blockConnecting, state);

     ................
}

PeerLogicValidation 的 SendMessage 方法里栅屏，發(fā)布Broadcast事件, 通知錢包重新發(fā)送未確認(rèn)的交易:

bool PeerLogicValidation::SendMessages(CNode* pto, std::atomic<bool>& interruptMsgProc)
{
    .............
    if (!fReindex && !fImporting && !IsInitialBlockDownload())
    {
            GetMainSignals().Broadcast(nTimeBestReceived, connman);
    }
    .............
}

從網(wǎng)絡(luò)上收到INV消息后飘千，通知給錢包，更新內(nèi)部狀態(tài)栈雳。

bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStream& vRecv, int64_t nTimeReceived, const CChainParams& chainparams, CConnman* connman, const std::atomic<bool>& interruptMsgProc)
{
            .................
            for (CInv &inv : vInv)
           {
               ............
               GetMainSignals().Inventory(inv.hash);

           }
            ................
}

validation.cpp 里面的 ProcessNewBlock在內(nèi)部調(diào)用 CheckBlock 后护奈，檢查失敗后，發(fā)布 BlockCheck s事件哥纫，通告給相關(guān)訂閱者霉旗。

bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<const CBlock> pblock, bool fForceProcessing, bool *fNewBlock)
{
      ............
      bool ret = CheckBlock(*pblock, state, chainparams.GetConsensus());
      if (!ret) {
            GetMainSignals().BlockChecked(*pblock, state);
            return error("%s: AcceptBlock FAILED (%s)", __func__, state.GetDebugMessage());
     }
      ...........

}

FlushStateToDisk, 發(fā)布SetBestChain 事件，通知錢包

bool static FlushStateToDisk(const CChainParams& chainparams, CValidationState &state, FlushStateMode mode, int nManualPruneHeight) {
     ...............
     if (fDoFullFlush || ((mode == FLUSH_STATE_ALWAYS || mode == FLUSH_STATE_PERIODIC) && nNow > nLastSetChain + (int64_t)DATABASE_WRITE_INTERVAL * 1000000)) {
        // Update best block in wallet (so we can detect restored wallets).
        GetMainSignals().SetBestChain(chainActive.GetLocator());
        nLastSetChain = nNow;
    }
     ...............
}

validation.cpp 里面的AcceptToMemoryPoolWorker, 在結(jié)束前蛀骇，發(fā)布TransactionAddedToMempool 事件厌秒。

static bool AcceptToMemoryPoolWorker(const CChainParams& chainparams, CTxMemPool& pool, CValidationState& state, const CTransactionRef& ptx,
                              bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced,
                              bool bypass_limits, const CAmount& nAbsurdFee, std::vector<COutPoint>& coins_to_uncache)
{
         ................
         GetMainSignals().TransactionAddedToMempool(ptx);

}

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原文鏈接:https://mp.weixin.qq.com/s/Gru2eMWLncqNbCbgdiBAGA

最后編輯于：2018.03.08 11:58:40

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