From 6b409f52ad80a35383043c488ea2eea7c14caba9 Mon Sep 17 00:00:00 2001
From: Gav Wood <i@gavwood.com>
Date: Sun, 29 Mar 2015 22:54:41 +0200
Subject: [PATCH] More descriptive errors on database fail. Fixes #1343

---
 libethcore/Exceptions.h    |  1 +
 libethereum/BlockChain.cpp | 17 +++++++++++++----
 libethereum/State.cpp      | 13 ++++++++++++-
 3 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/libethcore/Exceptions.h b/libethcore/Exceptions.h
index df6a08817..db2718fc4 100644
--- a/libethcore/Exceptions.h
+++ b/libethcore/Exceptions.h
@@ -38,6 +38,7 @@ using errinfo_difficulty = boost::error_info<struct tag_difficulty, u256>;
 using BadFieldError = boost::tuple<errinfo_field, errinfo_data>;
 
 struct DatabaseAlreadyOpen: virtual dev::Exception {};
+struct NotEnoughAvailableSpace: virtual dev::Exception {};
 struct NotEnoughCash: virtual dev::Exception {};
 struct GasPriceTooLow: virtual dev::Exception {};
 struct BlockGasLimitReached: virtual dev::Exception {};
diff --git a/libethereum/BlockChain.cpp b/libethereum/BlockChain.cpp
index 688a0c326..508531f9d 100644
--- a/libethereum/BlockChain.cpp
+++ b/libethereum/BlockChain.cpp
@@ -131,10 +131,19 @@ void BlockChain::open(std::string _path, bool _killExisting)
 	o.create_if_missing = true;
 	ldb::DB::Open(o, _path + "/blocks", &m_blocksDB);
 	ldb::DB::Open(o, _path + "/details", &m_extrasDB);
-	if (!m_blocksDB)
-		BOOST_THROW_EXCEPTION(DatabaseAlreadyOpen());
-	if (!m_extrasDB)
-		BOOST_THROW_EXCEPTION(DatabaseAlreadyOpen());
+	if (!m_blocksDB || !m_extrasDB)
+	{
+		if (boost::filesystem::space(_path + "/blocks").available < 1024)
+		{
+			cwarn << "Not enough available space found on hard drive. Please free some up and then re-run. Bailing.";
+			BOOST_THROW_EXCEPTION(NotEnoughAvailableSpace());
+		}
+		else
+		{
+			cwarn << "Database already open. You appear to have another instance of ethereum running. Bailing.";
+			BOOST_THROW_EXCEPTION(DatabaseAlreadyOpen());
+		}
+	}
 
 	if (!details(m_genesisHash))
 	{
diff --git a/libethereum/State.cpp b/libethereum/State.cpp
index 9817e2bad..378c60fa3 100644
--- a/libethereum/State.cpp
+++ b/libethereum/State.cpp
@@ -60,7 +60,18 @@ OverlayDB State::openDB(std::string _path, bool _killExisting)
 	ldb::DB* db = nullptr;
 	ldb::DB::Open(o, _path + "/state", &db);
 	if (!db)
-		BOOST_THROW_EXCEPTION(DatabaseAlreadyOpen());
+	{
+		if (boost::filesystem::space(_path + "/state").available < 1024)
+		{
+			cwarn << "Not enough available space found on hard drive. Please free some up and then re-run. Bailing.";
+			BOOST_THROW_EXCEPTION(NotEnoughAvailableSpace());
+		}
+		else
+		{
+			cwarn << "Database already open. You appear to have another instance of ethereum running. Bailing.";
+			BOOST_THROW_EXCEPTION(DatabaseAlreadyOpen());
+		}
+	}
 
 	cnote << "Opened state DB.";
 	return OverlayDB(db);