From 836ed9d6b70e3ae928624f9ed81ed206a66b85b8 Mon Sep 17 00:00:00 2001
From: obscuren <geffobscura@gmail.com>
Date: Fri, 22 Aug 2014 11:34:59 +0200
Subject: [PATCH] Write Protocol version to the db so we can perform sanity
 checks

---
 ethereum.go      | 12 +++++++++++-
 ethutil/value.go |  2 ++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/ethereum.go b/ethereum.go
index 1e1891589d..4c5e13b6df 100644
--- a/ethereum.go
+++ b/ethereum.go
@@ -90,7 +90,6 @@ type Ethereum struct {
 }
 
 func New(db ethutil.Database, clientIdentity ethwire.ClientIdentity, keyManager *ethcrypto.KeyManager, caps Caps, usePnp bool) (*Ethereum, error) {
-
 	var err error
 	var nat NAT
 
@@ -101,6 +100,8 @@ func New(db ethutil.Database, clientIdentity ethwire.ClientIdentity, keyManager
 		}
 	}
 
+	bootstrapDb(db)
+
 	ethutil.Config.Db = db
 
 	nonce, _ := ethutil.RandomUint64()
@@ -534,3 +535,12 @@ out:
 		}
 	}
 }
+
+func bootstrapDb(db ethutil.Database) {
+	d, _ := db.Get([]byte("ProtocolVersion"))
+	protov := ethutil.NewValue(d).Uint()
+
+	if protov == 0 {
+		db.Put([]byte("ProtocolVersion"), ethutil.NewValue(ProtocolVersion).Bytes())
+	}
+}
diff --git a/ethutil/value.go b/ethutil/value.go
index 608d332ba4..b336345cab 100644
--- a/ethutil/value.go
+++ b/ethutil/value.go
@@ -141,6 +141,8 @@ func (val *Value) Bytes() []byte {
 		return []byte(s)
 	} else if s, ok := val.Val.(*big.Int); ok {
 		return s.Bytes()
+	} else {
+		return big.NewInt(val.Int()).Bytes()
 	}
 
 	return []byte{}