Nicer import graph.

alethzero/DownloadView.cpp

@@ -52,7 +52,7 @@ void SyncView::paintEvent(QPaintEvent*)
 	unsigned syncVerified = syncImporting + bqs.verified;
 	unsigned syncVerifying = syncVerified + bqs.verifying;
 	unsigned syncUnverified = syncVerifying + bqs.unverified;
-	unsigned syncUnknown = syncUnverified + bqs.unknown;
+	unsigned syncCount = syncUnverified + bqs.unknown - syncFrom;
 
 	// best effort guess. assumes there's no forks.
 	unsigned downloadFrom = m_client->numberFromHash(m_client->isKnown(man->firstBlock()) ? man->firstBlock() : PendingBlockHash);
@@ -67,17 +67,19 @@ void SyncView::paintEvent(QPaintEvent*)
 	unsigned hashDone = hashFrom + (sync.state == SyncState::Hashes ? sync.hashesReceived : hashCount);
 
 	m_lastFrom = min(syncFrom, m_lastFrom);
+	m_lastTo = max(max(syncFrom + syncCount, hashFrom + hashCount), m_lastTo);
 	unsigned from = min(min(hashFrom, downloadFrom), min(syncFrom, m_lastFrom));
-	unsigned count = max(hashFrom + hashCount, downloadFrom + downloadCount) - from;
-	m_lastFrom = (m_lastFrom * 95 + syncFrom) / 100;
+	unsigned count = max(max(hashFrom + hashCount, downloadFrom + downloadCount), max(syncFrom + syncCount, m_lastTo)) - from;
+	m_lastFrom = (m_lastFrom * 99 + syncFrom * 1) / 100;
+	m_lastTo = (m_lastTo * 99 + max(syncFrom + syncCount, hashFrom + hashCount) * 1) / 100;
 
 	if (!count)
 	{
-		m_lastFrom = (unsigned)-1;
+		m_lastFrom = m_lastTo = (unsigned)-1;
 		return;
 	}
 
-	cnote << "Range " << from << "-" << (from + count);
+	cnote << "Range " << from << "-" << (from + count) << "(" << hashFrom << "+" << hashCount << "," << downloadFrom << "+" << downloadCount << "," << syncFrom << "+" << syncCount << ")";
 	auto r = [&](unsigned u) {
 		return toString((u - from) * 100 / count) + "%";
 	};
@@ -85,27 +87,48 @@ void SyncView::paintEvent(QPaintEvent*)
 	if (count)
 	{
 		cnote << "Hashes:" << r(hashDone) << "   Blocks:" << r(downloadFlank) << r(downloadDone) << r(downloadPoint);
-		cnote << "Importing:" << r(syncFrom) << r(syncImported) << r(syncImporting) << r(syncVerified) << r(syncVerifying) << r(syncUnverified) << r(syncUnknown);
+		cnote << "Importing:" << r(syncFrom) << r(syncImported) << r(syncImporting) << r(syncVerified) << r(syncVerifying) << r(syncUnverified);
 	}
 
-	if (!man || man->chainEmpty() || !man->subCount())
-		return;
-
-	float s = min(rect().width(), rect().height());
+	float squareSize = min(rect().width(), rect().height());
 	QPen pen;
 	pen.setCapStyle(Qt::FlatCap);
-	pen.setWidthF(s / 10);
-	p.setPen(pen);
+	pen.setWidthF(squareSize / 20);
 	auto middle = [&](float x) {
-		return QRectF(s / 2 - s / 2 * x, 0 + s / 2 - s / 2 * x, s * x, s * x);
+		return QRectF(squareSize / 2 - squareSize / 2 * x, 0 + squareSize / 2 - squareSize / 2 * x, squareSize * x, squareSize * x);
+	};
+
+	auto arcLen = [&](unsigned x) {
+		return x * -5760.f / count;
+	};
+	auto arcPos = [&](unsigned x) {
+		return int(90 * 16.f + arcLen(x - from)) % 5760;
 	};
 
-	auto toArc = [&](unsigned x) {
-		return (x - from) * -5760.f / count;
+	p.setPen(Qt::NoPen);
+	p.setBrush(QColor::fromHsv(0, 0, 210));
+	pen.setWidthF(0.f);
+	p.drawPie(middle(0.4f), arcPos(from), arcLen(hashDone - from));
+
+	auto progress = [&](unsigned h, unsigned s, unsigned v, float size, float thickness, unsigned nfrom, unsigned ncount) {
+		p.setBrush(Qt::NoBrush);
+		pen.setColor(QColor::fromHsv(h, s, v));
+		pen.setWidthF(squareSize * thickness);
+		p.setPen(pen);
+		p.drawArc(middle(size), arcPos(nfrom), arcLen(ncount));
 	};
-	const float arcFrom = 90 * 16.f;
-	p.drawArc(middle(0.5f), arcFrom, toArc(downloadDone));
-	p.drawPie(middle(0.2f), arcFrom, toArc(hashDone));
+
+	progress(0, 50, 170, 0.4f, 0.12f, downloadFlank, downloadPoint - downloadFlank);
+	progress(0, 0, 150, 0.4f, 0.10f, from, downloadDone - from);
+
+	progress(0, 0, 230, 0.7f, 0.090f, from, syncUnverified - from);
+	progress(60, 25, 210, 0.7f, 0.08f, from, syncVerifying - from);
+	progress(120, 25, 190, 0.7f, 0.07f, from, syncVerified - from);
+
+	progress(0, 0, 220, 0.9f, 0.02f, from, count);
+	progress(0, 0, 100, 0.9f, 0.04f, from, syncFrom - from);
+	progress(0, 50, 100, 0.9f, 0.08f, syncFrom, syncImporting - syncFrom);
+
 	return;
 
 	double ratio = (double)rect().width() / rect().height();

alethzero/DownloadView.h

@@ -51,4 +51,5 @@ private:
 	dev::eth::Client const* m_client = nullptr;
 
 	unsigned m_lastFrom = (unsigned)-1;
+	unsigned m_lastTo = (unsigned)-1;
 };

alethzero/Main.ui

@@ -199,6 +199,7 @@
     <addaction name="usePrivate"/>
     <addaction name="retryUnknown"/>
     <addaction name="confirm"/>
+    <addaction name="rewindChain"/>
    </widget>
    <widget class="QMenu" name="menu_View">
     <property name="title">
@@ -1804,6 +1805,11 @@ font-size: 14pt</string>
     <string>&amp;Sentinel...</string>
    </property>
   </action>
+  <action name="rewindChain">
+   <property name="text">
+    <string>&amp;Rewind Chain...</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <customwidgets>

alethzero/MainWin.cpp

@@ -1044,6 +1044,17 @@ void Main::on_vmInterpreter_triggered() { VMFactory::setKind(VMKind::Interpreter
 void Main::on_vmJIT_triggered() { VMFactory::setKind(VMKind::JIT); }
 void Main::on_vmSmart_triggered() { VMFactory::setKind(VMKind::Smart); }
 
+void Main::on_rewindChain_triggered()
+{
+	bool ok;
+	int n = QInputDialog::getInt(this, "Rewind Chain", "Enter the number of the new chain head.", ethereum()->number() * 9 / 10, 1, ethereum()->number(), 1, &ok);
+	if (ok)
+	{
+		ethereum()->rewind(n);
+		refreshAll();
+	}
+}
+
 void Main::on_urlEdit_returnPressed()
 {
 	QString s = ui->urlEdit->text();

alethzero/MainWin.h

@@ -187,6 +187,7 @@ private slots:
 	void on_vmInterpreter_triggered();
 	void on_vmJIT_triggered();
 	void on_vmSmart_triggered();
+	void on_rewindChain_triggered();
 
 	// Debugger
 	void on_debugCurrent_triggered();

libethereum/BlockChain.cpp

@@ -799,6 +799,25 @@ void BlockChain::clearBlockBlooms(unsigned _begin, unsigned _end)
 	}
 }
 
+void BlockChain::rewind(unsigned _newHead)
+{
+	DEV_WRITE_GUARDED(x_lastBlockHash)
+	{
+		if (_newHead >= m_lastBlockNumber)
+			return;
+		m_lastBlockHash = numberHash(_newHead);
+		m_lastBlockNumber = _newHead;
+		auto o = m_extrasDB->Put(m_writeOptions, ldb::Slice("best"), ldb::Slice((char const*)&m_lastBlockHash, 32));
+		if (!o.ok())
+		{
+			cwarn << "Error writing to extras database: " << o.ToString();
+			cout << "Put" << toHex(bytesConstRef(ldb::Slice("best"))) << "=>" << toHex(bytesConstRef(ldb::Slice((char const*)&m_lastBlockHash, 32)));
+			cwarn << "Fail writing to extras database. Bombing out.";
+			exit(-1);
+		}
+	}
+}
+
 tuple<h256s, h256, unsigned> BlockChain::treeRoute(h256 const& _from, h256 const& _to, bool _common, bool _pre, bool _post) const
 {
 //	cdebug << "treeRoute" << _from << "..." << _to;
@@ -1070,7 +1089,8 @@ bool BlockChain::isKnown(h256 const& _hash) const
 			if (d.empty())
 				return false;
 		}
-	return true;
+//	return true;
+	return details(_hash).number <= m_lastBlockNumber;		// to allow rewind functionality.
 }
 
 bytes BlockChain::block(h256 const& _hash) const

libethereum/BlockChain.h

@@ -215,6 +215,9 @@ public:
 	/// Will call _progress with the progress in this operation first param done, second total.
 	void rebuild(std::string const& _path, ProgressCallback const& _progress = std::function<void(unsigned, unsigned)>(), bool _prepPoW = false);
 
+	/// Alter the head of the chain to some prior block along it.
+	void rewind(unsigned _newHead);
+
 	/** @returns a tuple of:
 	 * - an vector of hashes of all blocks between @a _from and @a _to, all blocks are ordered first by a number of
 	 * blocks that are parent-to-child, then two sibling blocks, then a number of blocks that are child-to-parent;

libethereum/BlockQueue.cpp

@@ -215,8 +215,10 @@ ImportResult BlockQueue::import(bytesConstRef _block, BlockChain const& _bc, boo
 		return ImportResult::Malformed;
 	}
 
+	clog(BlockQueueTraceChannel) << "Block" << h << "is" << bi.number << "parent is" << bi.parentHash;
+
 	// Check block doesn't already exist first!
-	if (_bc.details(h))
+	if (_bc.isKnown(h))
 	{
 		cblockq << "Already known in chain.";
 		return ImportResult::AlreadyInChain;

libethereum/Client.h

@@ -217,6 +217,8 @@ public:
 	std::string const& sentinel() const { return m_sentinel; }
 	/// Set the extra data that goes into mined blocks.
 	void setExtraData(bytes const& _extraData) { m_extraData = _extraData; }
+	/// Rewind to a prior head.
+	void rewind(unsigned _n) { m_bc.rewind(_n); }
 
 protected:
 	/// InterfaceStub methods

libethereum/State.cpp

@@ -1212,6 +1212,7 @@ ExecutionResult State::execute(LastHashes const& _lh, Transaction const& _t, Per
 	uncommitToMine();
 
 	// OK - transaction looks valid - execute.
+	u256 startGasUsed = gasUsed();
 #if ETH_PARANOIA
 	ctrace << "Executing" << e.t() << "on" << h;
 	ctrace << toHex(e.t().rlp());
@@ -1261,7 +1262,7 @@ ExecutionResult State::execute(LastHashes const& _lh, Transaction const& _t, Per
 	
 		// Add to the user-originated transactions that we've executed.
 		m_transactions.push_back(e.t());
-		m_receipts.push_back(TransactionReceipt(rootHash(), e.gasUsed(), e.logs()));
+		m_receipts.push_back(TransactionReceipt(rootHash(), startGasUsed + e.gasUsed(), e.logs()));
 		m_transactionSet.insert(e.t().sha3());
 	}