core: added basic chain configuration

Added chain configuration options and write out during genesis database
insertion. If no "config" was found, nothing is written to the database.

Configurations are written on a per genesis base. This means
that any chain (which is identified by it's genesis hash) can have their
own chain settings.

1 files changed, 23 insertions, 4 deletions

diff --git a/core/chain_makers.go b/core/chain_makers.go
index 7ae3c98b0..c740f9c37 100644
--- a/core/chain_makers.go
+++ b/core/chain_makers.go
@@ -23,11 +23,30 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/pow"
 )
 
+/*
+ * TODO: move this to another package.
+ */
+
+// MakeChainConfig returns a new ChainConfig with the ethereum default chain settings.
+func MakeChainConfig(testnet bool) *ChainConfig {
+	homesteadBlock := params.MainNetHomesteadBlock
+	// set a different default homestead block for the testnet
+	if testnet {
+		homesteadBlock = params.TestNetHomesteadBlock
+	}
+
+	return &ChainConfig{
+		HomesteadBlock: homesteadBlock,
+	}
+}
+
 // FakePow is a non-validating proof of work implementation.
 // It returns true from Verify for any block.
 type FakePow struct{}
@@ -91,7 +110,7 @@ func (b *BlockGen) AddTx(tx *types.Transaction) {
 		b.SetCoinbase(common.Address{})
 	}
 	b.statedb.StartRecord(tx.Hash(), common.Hash{}, len(b.txs))
-	receipt, _, _, err := ApplyTransaction(nil, b.gasPool, b.statedb, b.header, tx, b.header.GasUsed, nil)
+	receipt, _, _, err := ApplyTransaction(MakeChainConfig(true), nil, b.gasPool, b.statedb, b.header, tx, b.header.GasUsed, vm.Config{})
 	if err != nil {
 		panic(err)
 	}
@@ -148,7 +167,7 @@ func (b *BlockGen) OffsetTime(seconds int64) {
 	if b.header.Time.Cmp(b.parent.Header().Time) <= 0 {
 		panic("block time out of range")
 	}
-	b.header.Difficulty = CalcDifficulty(b.header.Time.Uint64(), b.parent.Time().Uint64(), b.parent.Number(), b.parent.Difficulty())
+	b.header.Difficulty = CalcDifficulty(MakeChainConfig(true), b.header.Time.Uint64(), b.parent.Time().Uint64(), b.parent.Number(), b.parent.Difficulty())
 }
 
 // GenerateChain creates a chain of n blocks. The first block's
@@ -203,7 +222,7 @@ func makeHeader(parent *types.Block, state *state.StateDB) *types.Header {
 		Root:       state.IntermediateRoot(),
 		ParentHash: parent.Hash(),
 		Coinbase:   parent.Coinbase(),
-		Difficulty: CalcDifficulty(time.Uint64(), new(big.Int).Sub(time, big.NewInt(10)).Uint64(), parent.Number(), parent.Difficulty()),
+		Difficulty: CalcDifficulty(MakeChainConfig(true), time.Uint64(), new(big.Int).Sub(time, big.NewInt(10)).Uint64(), parent.Number(), parent.Difficulty()),
 		GasLimit:   CalcGasLimit(parent),
 		GasUsed:    new(big.Int),
 		Number:     new(big.Int).Add(parent.Number(), common.Big1),
@@ -222,7 +241,7 @@ func newCanonical(n int, full bool) (ethdb.Database, *BlockChain, error) {
 	// Initialize a fresh chain with only a genesis block
 	genesis, _ := WriteTestNetGenesisBlock(db)
 
-	blockchain, _ := NewBlockChain(db, FakePow{}, evmux)
+	blockchain, _ := NewBlockChain(db, MakeChainConfig(false), FakePow{}, evmux)
 	// Create and inject the requested chain
 	if n == 0 {
 		return db, blockchain, nil