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.

13 files changed, 72 insertions, 56 deletions

diff --git a/core/vm/environment.go b/core/vm/environment.go
index 568218edd..747627565 100644
--- a/core/vm/environment.go
+++ b/core/vm/environment.go
@@ -22,9 +22,17 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
+// RuleSet is an interface that defines the current rule set during the
+// execution of the EVM instructions (e.g. whether it's homestead)
+type RuleSet interface {
+	IsHomestead(*big.Int) bool
+}
+
 // Environment is an EVM requirement and helper which allows access to outside
 // information such as states.
 type Environment interface {
+	// The current ruleset
+	RuleSet() RuleSet
 	// The state database
 	Db() Database
 	// Creates a restorable snapshot
@@ -53,10 +61,10 @@ type Environment interface {
 	AddLog(*Log)
 	// Type of the VM
 	Vm() Vm
-	// Current calling depth
+	// Get the curret calling depth
 	Depth() int
+	// Set the current calling depth
 	SetDepth(i int)
-
 	// Call another contract
 	Call(me ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
 	// Take another's contract code and execute within our own context
diff --git a/core/vm/instructions.go b/core/vm/instructions.go
index c4b4339a2..942fafde7 100644
--- a/core/vm/instructions.go
+++ b/core/vm/instructions.go
@@ -520,7 +520,7 @@ func opCreate(instr instruction, pc *uint64, env Environment, contract *Contract
 	// homestead we must check for CodeStoreOutOfGasError (homestead only
 	// rule) and treat as an error, if the ruleset is frontier we must
 	// ignore this error and pretend the operation was successful.
-	if params.IsHomestead(env.BlockNumber()) && suberr == CodeStoreOutOfGasError {
+	if env.RuleSet().IsHomestead(env.BlockNumber()) && suberr == CodeStoreOutOfGasError {
 		stack.push(new(big.Int))
 	} else if suberr != nil && suberr != CodeStoreOutOfGasError {
 		stack.push(new(big.Int))
diff --git a/core/vm/jit.go b/core/vm/jit.go
index 71ffcf0f6..ac2083f54 100644
--- a/core/vm/jit.go
+++ b/core/vm/jit.go
@@ -30,27 +30,24 @@ import (
 	"github.com/hashicorp/golang-lru"
 )
 
+// progStatus is the type for the JIT program status.
 type progStatus int32
 
 const (
-	progUnknown progStatus = iota
-	progCompile
-	progReady
-	progError
+	progUnknown progStatus = iota // unknown status
+	progCompile                   // compile status
+	progReady                     // ready for use status
+	progError                     // error status (usually caused during compilation)
 
-	defaultJitMaxCache int = 64
+	defaultJitMaxCache int = 64 // maximum amount of jit cached programs
 )
 
-var (
-	EnableJit   bool // Enables the JIT VM
-	ForceJit    bool // Force the JIT, skip byte VM
-	MaxProgSize int  // Max cache size for JIT Programs
-)
+var MaxProgSize int // Max cache size for JIT programs
 
-var programs *lru.Cache
+var programs *lru.Cache // lru cache for the JIT programs.
 
 func init() {
-	programs, _ = lru.New(defaultJitMaxCache)
+	SetJITCacheSize(defaultJitMaxCache)
 }
 
 // SetJITCacheSize recreates the program cache with the max given size. Setting
@@ -322,7 +319,7 @@ func runProgram(program *Program, pcstart uint64, mem *Memory, stack *stack, env
 		}()
 	}
 
-	homestead := params.IsHomestead(env.BlockNumber())
+	homestead := env.RuleSet().IsHomestead(env.BlockNumber())
 	for pc < uint64(len(program.instructions)) {
 		instrCount++
 
diff --git a/core/vm/jit_test.go b/core/vm/jit_test.go
index 43b1dee2a..c503a3a81 100644
--- a/core/vm/jit_test.go
+++ b/core/vm/jit_test.go
@@ -84,7 +84,7 @@ func TestCompiling(t *testing.T) {
 func TestResetInput(t *testing.T) {
 	var sender account
 
-	env := NewEnv()
+	env := NewEnv(false, true)
 	contract := NewContract(sender, sender, big.NewInt(100), big.NewInt(10000), big.NewInt(0))
 	contract.CodeAddr = &common.Address{}
 
@@ -143,10 +143,7 @@ func runVmBench(test vmBench, b *testing.B) {
 	if test.precompile && !test.forcejit {
 		NewProgram(test.code)
 	}
-	env := NewEnv()
-
-	EnableJit = !test.nojit
-	ForceJit = test.forcejit
+	env := NewEnv(test.nojit, test.forcejit)
 
 	b.ResetTimer()
 
@@ -168,12 +165,16 @@ type Env struct {
 	evm      *EVM
 }
 
-func NewEnv() *Env {
+func NewEnv(noJit, forceJit bool) *Env {
 	env := &Env{gasLimit: big.NewInt(10000), depth: 0}
-	env.evm = New(env, nil)
+	env.evm = New(env, Config{
+		EnableJit: !noJit,
+		ForceJit:  forceJit,
+	})
 	return env
 }
 
+func (self *Env) RuleSet() RuleSet       { return ruleSet{new(big.Int)} }
 func (self *Env) Vm() Vm                 { return self.evm }
 func (self *Env) Origin() common.Address { return common.Address{} }
 func (self *Env) BlockNumber() *big.Int  { return big.NewInt(0) }
diff --git a/core/vm/jump_table.go b/core/vm/jump_table.go
index 8297d3e1d..2c3796679 100644
--- a/core/vm/jump_table.go
+++ b/core/vm/jump_table.go
@@ -1,10 +1,6 @@
 package vm
 
-import (
-	"math/big"
-
-	"github.com/ethereum/go-ethereum/params"
-)
+import "math/big"
 
 type jumpPtr struct {
 	fn    instrFn
@@ -13,12 +9,12 @@ type jumpPtr struct {
 
 type vmJumpTable [256]jumpPtr
 
-func newJumpTable(blockNumber *big.Int) vmJumpTable {
+func newJumpTable(ruleset RuleSet, blockNumber *big.Int) vmJumpTable {
 	var jumpTable vmJumpTable
 
 	// when initialising a new VM execution we must first check the homestead
 	// changes.
-	if params.IsHomestead(blockNumber) {
+	if ruleset.IsHomestead(blockNumber) {
 		jumpTable[DELEGATECALL] = jumpPtr{opDelegateCall, true}
 	}
 
diff --git a/core/vm/jump_table_test.go b/core/vm/jump_table_test.go
index 2ed1b26fc..2386a7525 100644
--- a/core/vm/jump_table_test.go
+++ b/core/vm/jump_table_test.go
@@ -3,20 +3,16 @@ package vm
 import (
 	"math/big"
 	"testing"
-
-	"github.com/ethereum/go-ethereum/params"
 )
 
 func TestInit(t *testing.T) {
-	params.HomesteadBlock = big.NewInt(1)
-
-	jumpTable := newJumpTable(big.NewInt(0))
+	jumpTable := newJumpTable(ruleSet{big.NewInt(1)}, big.NewInt(0))
 	if jumpTable[DELEGATECALL].valid {
 		t.Error("Expected DELEGATECALL not to be present")
 	}
 
 	for _, n := range []int64{1, 2, 100} {
-		jumpTable := newJumpTable(big.NewInt(n))
+		jumpTable := newJumpTable(ruleSet{big.NewInt(1)}, big.NewInt(n))
 		if !jumpTable[DELEGATECALL].valid {
 			t.Error("Expected DELEGATECALL to be present for block", n)
 		}
diff --git a/core/vm/logger.go b/core/vm/logger.go
index 8d333dfd2..cbdc8a744 100644
--- a/core/vm/logger.go
+++ b/core/vm/logger.go
@@ -89,7 +89,7 @@ func newLogger(cfg LogConfig, env Environment) *Logger {
 // captureState logs a new structured log message and pushes it out to the environment
 //
 // captureState also tracks SSTORE ops to track dirty values.
-func (l *Logger) captureState(pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *stack, contract *Contract, err error) {
+func (l *Logger) captureState(pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *stack, contract *Contract, depth int, err error) {
 	// short circuit if no log collector is present
 	if l.cfg.Collector == nil {
 		return
diff --git a/core/vm/logger_test.go b/core/vm/logger_test.go
index 77fee2c64..144569865 100644
--- a/core/vm/logger_test.go
+++ b/core/vm/logger_test.go
@@ -47,7 +47,7 @@ type dummyEnv struct {
 
 func newDummyEnv(ref *dummyContractRef) *dummyEnv {
 	return &dummyEnv{
-		Env: NewEnv(),
+		Env: NewEnv(true, false),
 		ref: ref,
 	}
 }
@@ -58,7 +58,7 @@ func (d dummyEnv) AddStructLog(StructLog) {}
 
 func TestStoreCapture(t *testing.T) {
 	var (
-		env      = NewEnv()
+		env      = NewEnv(true, false)
 		logger   = newLogger(LogConfig{Collector: env}, env)
 		mem      = NewMemory()
 		stack    = newstack()
@@ -69,7 +69,7 @@ func TestStoreCapture(t *testing.T) {
 
 	var index common.Hash
 
-	logger.captureState(0, SSTORE, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	logger.captureState(0, SSTORE, new(big.Int), new(big.Int), mem, stack, contract, 0, nil)
 	if len(logger.changedValues[contract.Address()]) == 0 {
 		t.Fatalf("expected exactly 1 changed value on address %x, got %d", contract.Address(), len(logger.changedValues[contract.Address()]))
 	}
@@ -91,13 +91,13 @@ func TestStorageCapture(t *testing.T) {
 		stack    = newstack()
 	)
 
-	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, 0, nil)
 	if ref.calledForEach {
 		t.Error("didn't expect for each to be called")
 	}
 
 	logger = newLogger(LogConfig{Collector: env, FullStorage: true}, env)
-	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, 0, nil)
 	if !ref.calledForEach {
 		t.Error("expected for each to be called")
 	}
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)
 	}
diff --git a/core/vm/util_test.go b/core/vm/util_test.go
new file mode 100644
index 000000000..3da742bfa
--- /dev/null
+++ b/core/vm/util_test.go
@@ -0,0 +1,9 @@
+package vm
+
+import "math/big"
+
+type ruleSet struct {
+	hs *big.Int
+}
+
+func (r ruleSet) IsHomestead(n *big.Int) bool { return n.Cmp(r.hs) >= 0 }
diff --git a/core/vm/vm.go b/core/vm/vm.go
index f72c853a2..0f93715d6 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -43,18 +43,13 @@ type Config struct {
 type EVM struct {
 	env       Environment
 	jumpTable vmJumpTable
-	cfg       *Config
+	cfg       Config
 
 	logger *Logger
 }
 
 // New returns a new instance of the EVM.
-func New(env Environment, cfg *Config) *EVM {
-	// initialise a default config if none is present
-	if cfg == nil {
-		cfg = new(Config)
-	}
-
+func New(env Environment, cfg Config) *EVM {
 	var logger *Logger
 	if cfg.Debug {
 		logger = newLogger(cfg.Logger, env)
@@ -62,7 +57,7 @@ func New(env Environment, cfg *Config) *EVM {
 
 	return &EVM{
 		env:       env,
-		jumpTable: newJumpTable(env.BlockNumber()),
+		jumpTable: newJumpTable(env.RuleSet(), env.BlockNumber()),
 		cfg:       cfg,
 		logger:    logger,
 	}
@@ -154,7 +149,7 @@ func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) {
 	// User defer pattern to check for an error and, based on the error being nil or not, use all gas and return.
 	defer func() {
 		if err != nil && evm.cfg.Debug {
-			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, err)
+			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, evm.env.Depth(), err)
 		}
 	}()
 
@@ -196,7 +191,7 @@ func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) {
 		mem.Resize(newMemSize.Uint64())
 		// Add a log message
 		if evm.cfg.Debug {
-			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, nil)
+			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, evm.env.Depth(), nil)
 		}
 
 		if opPtr := evm.jumpTable[op]; opPtr.valid {
diff --git a/core/vm/vm_jit_fake.go b/core/vm/vm_jit_fake.go
index b26cf1ad0..4fa98ccd9 100644
--- a/core/vm/vm_jit_fake.go
+++ b/core/vm/vm_jit_fake.go
@@ -22,5 +22,5 @@ import "fmt"
 
 func NewJitVm(env Environment) VirtualMachine {
 	fmt.Printf("Warning! EVM JIT not enabled.\n")
-	return New(env, nil)
+	return New(env, Config{})
 }