[#88] container: Migrate container and eACL structures

In v0.8.0:
  - containers were stored as stable marshaled binary,

In v0.9.0:
  - containers are stored the same way as eACL,
  - eACL structure has new `token []byte field`.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

container/container_contract.go

@@ -64,7 +64,10 @@ var (
 )
 
 func _deploy(data interface{}, isUpdate bool) {
+	ctx := storage.GetContext()
+
 	if isUpdate {
+		migrateContainerAndEACLStructures(ctx) // from v0.8.0 to v0.9.0
 		return
 	}
 
@@ -75,8 +78,6 @@ func _deploy(data interface{}, isUpdate bool) {
 	addrBalance := args[3].(interop.Hash160)
 	addrID := args[4].(interop.Hash160)
 
-	ctx := storage.GetContext()
-
 	if !common.HasUpdateAccess(ctx) {
 		panic("only owner can reinitialize contract")
 	}
@@ -100,6 +101,34 @@ func _deploy(data interface{}, isUpdate bool) {
 	runtime.Log("container contract initialized")
 }
 
+func migrateContainerAndEACLStructures(ctx storage.Context) {
+	eACLKeyLength := containerIDSize + len(eACLPrefix)
+
+	it := storage.Find(ctx, []byte{}, storage.None)
+	for iterator.Next(it) {
+		pair := iterator.Value(it).([]interface{})
+		key := pair[0].([]byte)
+
+		switch len(key) {
+		case containerIDSize: // migrate containers
+			val := pair[1].([]byte)
+			newContainer := Container{value: val}
+
+			common.SetSerialized(ctx, key, newContainer)
+		case eACLKeyLength: // migrate eACLs
+			val := pair[1].([]byte)
+			eacl := std.Deserialize(val).(ExtendedACL)
+			newEACL := ExtendedACL{
+				value: eacl.value,
+				sig:   eacl.sig,
+				pub:   eacl.pub,
+			}
+
+			common.SetSerialized(ctx, key, newEACL)
+		}
+	}
+}
+
 func Migrate(script []byte, manifest []byte, data interface{}) bool {
 	ctx := storage.GetReadOnlyContext()