Make ValidationInterface signals-type-agnostic

(by hiding boost::signals stuff in the .cpp)

This allows us to give it a bit more intelligence as we move
forward, including routing some signals through CScheduler. While
the introduction of a "internals" pointer in the class is pretty
ugly, the fact that we no longer need to include boost/signals
directly from validationinterface.h is very much worth the loss.

1 files changed, 36 insertions, 26 deletions

diff --git a/src/validationinterface.h b/src/validationinterface.h
index 17545018df..c248781a48 100644
--- a/src/validationinterface.h
+++ b/src/validationinterface.h
@@ -6,7 +6,6 @@
 #ifndef BITCOIN_VALIDATIONINTERFACE_H
 #define BITCOIN_VALIDATIONINTERFACE_H
 
-#include <boost/signals2/signal.hpp>
 #include <memory>
 
 #include "primitives/transaction.h" // CTransaction(Ref)
@@ -32,49 +31,60 @@ void UnregisterAllValidationInterfaces();
 
 class CValidationInterface {
 protected:
-    virtual void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {}
-    virtual void TransactionAddedToMempool(const CTransactionRef &ptxn) {}
-    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();
-};
-
-struct CMainSignals {
     /** Notifies listeners of updated block chain tip */
-    boost::signals2::signal<void (const CBlockIndex *, const CBlockIndex *, bool fInitialDownload)> UpdatedBlockTip;
+    virtual void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {}
     /** Notifies listeners of a transaction having been added to mempool. */
-    boost::signals2::signal<void (const CTransactionRef &)> TransactionAddedToMempool;
+    virtual void TransactionAddedToMempool(const CTransactionRef &ptxn) {}
     /**
      * Notifies listeners of a block being connected.
      * Provides a vector of transactions evicted from the mempool as a result.
      */
-    boost::signals2::signal<void (const std::shared_ptr<const CBlock> &, const CBlockIndex *pindex, const std::vector<CTransactionRef> &)> BlockConnected;
+    virtual void BlockConnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex *pindex, const std::vector<CTransactionRef> &txnConflicted) {}
     /** Notifies listeners of a block being disconnected */
-    boost::signals2::signal<void (const std::shared_ptr<const CBlock> &)> BlockDisconnected;
-    /** Notifies listeners of a new active block chain. */
-    boost::signals2::signal<void (const CBlockLocator &)> SetBestChain;
+    virtual void BlockDisconnected(const std::shared_ptr<const CBlock> &block) {}
+    /** Notifies listeners of the new active block chain on-disk. */
+    virtual void SetBestChain(const CBlockLocator &locator) {}
     /** Notifies listeners about an inventory item being seen on the network. */
-    boost::signals2::signal<void (const uint256 &)> Inventory;
+    virtual void Inventory(const uint256 &hash) {}
     /** Tells listeners to broadcast their data. */
-    boost::signals2::signal<void (int64_t nBestBlockTime, CConnman* connman)> Broadcast;
+    virtual void ResendWalletTransactions(int64_t nBestBlockTime, CConnman* connman) {}
     /**
      * Notifies listeners of a block validation result.
      * If the provided CValidationState IsValid, the provided block
      * is guaranteed to be the current best block at the time the
      * callback was generated (not necessarily now)
      */
-    boost::signals2::signal<void (const CBlock&, const CValidationState&)> BlockChecked;
+    virtual void BlockChecked(const CBlock&, const CValidationState&) {}
     /**
      * Notifies listeners that a block which builds directly on our current tip
      * has been received and connected to the headers tree, though not validated yet */
-    boost::signals2::signal<void (const CBlockIndex *, const std::shared_ptr<const CBlock>&)> NewPoWValidBlock;
+    virtual void NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& block) {};
+    friend void ::RegisterValidationInterface(CValidationInterface*);
+    friend void ::UnregisterValidationInterface(CValidationInterface*);
+    friend void ::UnregisterAllValidationInterfaces();
+};
+
+struct MainSignalsInstance;
+class CMainSignals {
+private:
+    std::unique_ptr<MainSignalsInstance> m_internals;
+
+    friend void ::RegisterValidationInterface(CValidationInterface*);
+    friend void ::UnregisterValidationInterface(CValidationInterface*);
+    friend void ::UnregisterAllValidationInterfaces();
+public:
+    CMainSignals();
+
+    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::vector<CTransactionRef> &);
+    void BlockDisconnected(const std::shared_ptr<const CBlock> &);
+    void UpdatedTransaction(const uint256 &);
+    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>&);
 };
 
 CMainSignals& GetMainSignals();