Fix mining deadlocks.

Cleanups and additional diagnostics for the BadRoot problems.

libdevcore/Exceptions.h

@@ -56,7 +56,7 @@ DEV_SIMPLE_EXCEPTION(BadHexCharacter);
 DEV_SIMPLE_EXCEPTION(NoNetworking);
 DEV_SIMPLE_EXCEPTION(NoUPnPDevice);
 DEV_SIMPLE_EXCEPTION(RootNotFound);
-DEV_SIMPLE_EXCEPTION(BadRoot);
+struct BadRoot: virtual Exception { public: BadRoot(h256 const& _root): Exception("BadRoot " + _root.hex()), root(_root) {} h256 root; };
 DEV_SIMPLE_EXCEPTION(FileError);
 DEV_SIMPLE_EXCEPTION(Overflow);
 DEV_SIMPLE_EXCEPTION(FailedInvariant);

libdevcore/TrieDB.h

@@ -96,7 +96,7 @@ public:
 	/// True if the trie is initialised but empty (i.e. that the DB contains the root node which is empty).
 	bool isEmpty() const { return m_root == c_shaNull && node(m_root).size(); }
 
-	h256 const& root() const { if (node(m_root).empty()) BOOST_THROW_EXCEPTION(BadRoot()); /*std::cout << "Returning root as " << ret << " (really " << m_root << ")" << std::endl;*/ return m_root; }	// patch the root in the case of the empty trie. TODO: handle this properly.
+	h256 const& root() const { if (node(m_root).empty()) BOOST_THROW_EXCEPTION(BadRoot(m_root)); /*std::cout << "Returning root as " << ret << " (really " << m_root << ")" << std::endl;*/ return m_root; }	// patch the root in the case of the empty trie. TODO: handle this properly.
 
 	std::string at(bytes const& _key) const { return at(&_key); }
 	std::string at(bytesConstRef _key) const;

libethcore/EthashSealEngine.cpp

@@ -63,7 +63,7 @@ void EthashSealEngine::onSealGenerated(std::function<void(bytes const&)> const&
 {
 	m_farm.onSolutionFound([=](EthashProofOfWork::Solution const& sol)
 	{
-		cdebug << m_farm.work().seedHash << m_farm.work().headerHash << sol.nonce << EthashAux::eval(m_farm.work().seedHash, m_farm.work().headerHash, sol.nonce).value;
+//		cdebug << m_farm.work().seedHash << m_farm.work().headerHash << sol.nonce << EthashAux::eval(m_farm.work().seedHash, m_farm.work().headerHash, sol.nonce).value;
 		m_sealing.m_mixHash = sol.mixHash;
 		m_sealing.m_nonce = sol.nonce;
 		RLPStream ret;

libethcore/Miner.h

@@ -58,6 +58,8 @@ public:
 	using Solution = typename PoW::Solution;
 	using Miner = GenericMiner<PoW>;
 
+	virtual ~GenericFarmFace() {}
+
 	/**
 	 * @brief Called from a Miner to note a WorkPackage has a solution.
 	 * @param _p The solution.

libethcore/Sealer.h

@@ -38,6 +38,8 @@ class BlockInfo;
 class SealEngineFace
 {
 public:
+	virtual ~SealEngineFace() {}
+
 	virtual std::string name() const = 0;
 	virtual unsigned revision() const = 0;
 	virtual unsigned sealFields() const = 0;

libethereum/BlockChain.cpp

@@ -586,9 +586,11 @@ ImportRoute BlockChain::import(VerifiedBlockRef const& _block, OverlayDB const&
 #endif
 	}
 #if ETH_CATCH
-	catch (BadRoot&)
+	catch (BadRoot& ex)
 	{
-		cwarn << "BadRoot error. Retrying import later.";
+		cwarn << "*** BadRoot error! Trying to import" << _block.info.hash() << "needed root" << ex.root;
+		cwarn << _block.info;
+		// Attempt in import later.
 		BOOST_THROW_EXCEPTION(FutureTime());
 	}
 	catch (Exception& ex)
@@ -1245,6 +1247,7 @@ State BlockChain::genesisState(OverlayDB const& _db)
 	dev::eth::commit(m_genesisState, ret.m_state);		// bit horrible. maybe consider a better way of constructing it?
 	ret.m_state.db()->commit();			// have to use this db() since it's the one that has been altered with the above commit.
 	ret.m_previousBlock = BlockInfo(&m_genesisBlock);
+	ret.resetCurrent();
 	return ret;
 }
 

libethereum/Client.cpp

@@ -586,7 +586,7 @@ void Client::onNewBlocks(h256s const& _blocks, h256Hash& io_changed)
 		appendFromBlock(h, BlockPolarity::Live, io_changed);
 }
 
-void Client::restartMining()
+void Client::resyncStateFromChain()
 {
 	// RESTART MINING
 
@@ -639,7 +639,7 @@ void Client::onChainChanged(ImportRoute const& _ir)
 		m_tq.dropGood(t);
 	}
 	onNewBlocks(_ir.liveBlocks, changeds);
-	restartMining();
+	resyncStateFromChain();
 	noteChanged(changeds);
 }
 

libethereum/Client.h

@@ -250,7 +250,7 @@ protected:
 	void onNewBlocks(h256s const& _blocks, h256Hash& io_changed);
 
 	/// Called after processing blocks by onChainChanged(_ir)
-	void restartMining();
+	void resyncStateFromChain();
 
 	/// Magically called when the chain has changed. An import route is provided.
 	/// Called by either submitWork() or in our main thread through syncBlockQueue().