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Diffstat (limited to 'ethchain/state.go')
-rw-r--r--ethchain/state.go51
1 files changed, 50 insertions, 1 deletions
diff --git a/ethchain/state.go b/ethchain/state.go
index cff192b54..4cd2c58ef 100644
--- a/ethchain/state.go
+++ b/ethchain/state.go
@@ -5,16 +5,46 @@ import (
"math/big"
)
+// States within the ethereum protocol are used to store anything
+// within the merkle trie. States take care of caching and storing
+// nested states. It's the general query interface to retrieve:
+// * Contracts
+// * Accounts
type State struct {
+ // The trie for this structure
trie *ethutil.Trie
+ // Nested states
+ states map[string]*State
}
+// Create a new state from a given trie
func NewState(trie *ethutil.Trie) *State {
- return &State{trie: trie}
+ return &State{trie: trie, states: make(map[string]*State)}
}
+// Resets the trie and all siblings
func (s *State) Reset() {
s.trie.Undo()
+
+ // Reset all nested states
+ for _, state := range s.states {
+ state.Reset()
+ }
+}
+
+// Syncs the trie and all siblings
+func (s *State) Sync() {
+ s.trie.Sync()
+
+ // Sync all nested states
+ for _, state := range s.states {
+ state.Sync()
+ }
+}
+
+// Purges the current trie.
+func (s *State) Purge() int {
+ return s.trie.NewIterator().Purge()
}
func (s *State) GetContract(addr []byte) *Contract {
@@ -23,9 +53,28 @@ func (s *State) GetContract(addr []byte) *Contract {
return nil
}
+ // Whet get contract is called the retrieved value might
+ // be an account. The StateManager uses this to check
+ // to see if the address a tx was sent to is a contract
+ // or an account
+ value := ethutil.NewValueFromBytes([]byte(data))
+ if value.Len() == 2 {
+ return nil
+ }
+
+ // build contract
contract := &Contract{}
contract.RlpDecode([]byte(data))
+ // Check if there's a cached state for this contract
+ cachedState := s.states[string(addr)]
+ if cachedState != nil {
+ contract.state = cachedState
+ } else {
+ // If it isn't cached, cache the state
+ s.states[string(addr)] = contract.state
+ }
+
return contract
}