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.

2 files changed, 17 insertions, 3 deletions

diff --git a/core/vm/runtime/env.go b/core/vm/runtime/env.go
index ce64d7117..1e943940b 100644
--- a/core/vm/runtime/env.go
+++ b/core/vm/runtime/env.go
@@ -27,8 +27,9 @@ import (
 
 // Env is a basic runtime environment required for running the EVM.
 type Env struct {
-	depth int
-	state *state.StateDB
+	ruleSet vm.RuleSet
+	depth   int
+	state   *state.StateDB
 
 	origin   common.Address
 	coinbase common.Address
@@ -48,6 +49,7 @@ type Env struct {
 // NewEnv returns a new vm.Environment
 func NewEnv(cfg *Config, state *state.StateDB) vm.Environment {
 	env := &Env{
+		ruleSet:    cfg.RuleSet,
 		state:      state,
 		origin:     cfg.Origin,
 		coinbase:   cfg.Coinbase,
@@ -56,7 +58,7 @@ func NewEnv(cfg *Config, state *state.StateDB) vm.Environment {
 		difficulty: cfg.Difficulty,
 		gasLimit:   cfg.GasLimit,
 	}
-	env.evm = vm.New(env, &vm.Config{
+	env.evm = vm.New(env, vm.Config{
 		Debug:     cfg.Debug,
 		EnableJit: !cfg.DisableJit,
 		ForceJit:  !cfg.DisableJit,
@@ -77,6 +79,7 @@ func (self *Env) AddStructLog(log vm.StructLog) {
 	self.logs = append(self.logs, log)
 }
 
+func (self *Env) RuleSet() vm.RuleSet      { return self.ruleSet }
 func (self *Env) Vm() vm.Vm                { return self.evm }
 func (self *Env) Origin() common.Address   { return self.origin }
 func (self *Env) BlockNumber() *big.Int    { return self.number }
diff --git a/core/vm/runtime/runtime.go b/core/vm/runtime/runtime.go
index f88a20170..553864a83 100644
--- a/core/vm/runtime/runtime.go
+++ b/core/vm/runtime/runtime.go
@@ -22,13 +22,20 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 )
 
+// The default, always homestead, rule set for the vm env
+type ruleSet struct{}
+
+func (ruleSet) IsHomestead(*big.Int) bool { return true }
+
 // Config is a basic type specifying certain configuration flags for running
 // the EVM.
 type Config struct {
+	RuleSet     vm.RuleSet
 	Difficulty  *big.Int
 	Origin      common.Address
 	Coinbase    common.Address
@@ -46,6 +53,10 @@ type Config struct {
 
 // sets defaults on the config
 func setDefaults(cfg *Config) {
+	if cfg.RuleSet == nil {
+		cfg.RuleSet = ruleSet{}
+	}
+
 	if cfg.Difficulty == nil {
 		cfg.Difficulty = new(big.Int)
 	}