Add SAE factory with state-sync stubs (#5604)

Author: StephenButtolph

vms/saevm/cchain/BUILD.bazel

@@ -22,9 +22,11 @@ go_library(
     srcs = [
         "api.go",
         "config.go",
+        "factory.go",
         "genesis.go",
         "gossip.go",
         "hooks.go",
+        "sync.go",
         "vm.go",
         "warp.go",
     ],
@@ -66,12 +68,14 @@ go_library(
         "//utils/logging",
         "//utils/rpc",
         "//utils/set",
+        "//vms",
         "//vms/components/avax",
         "//vms/components/gas",
         "//vms/evm/acp176",
         "//vms/evm/acp226",
         "//vms/evm/database",
         "//vms/platformvm/warp",
+        "//vms/saevm/adaptor",
         "//vms/saevm/blocks",
         "//vms/saevm/cchain/dynamic",
         "//vms/saevm/cchain/state",

vms/saevm/cchain/factory.go

@@ -0,0 +1,36 @@
+// Copyright (C) 2019, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package cchain
+
+import (
+	"time"
+
+	"github.com/ava-labs/avalanchego/snow/engine/snowman/block"
+	"github.com/ava-labs/avalanchego/utils/logging"
+	"github.com/ava-labs/avalanchego/vms"
+	"github.com/ava-labs/avalanchego/vms/saevm/adaptor"
+)
+
+var _ vms.Factory = (*Factory)(nil)
+
+// Factory creates new C-Chain VMs.
+type Factory struct{}
+
+// New creates a new C-Chain VM.
+func (*Factory) New(log logging.Logger) (interface{}, error) {
+	log.Info("Creating new C-Chain SAE VM")
+	vm := &VM{
+		pullGossipPeriod: time.Second,
+		pushGossipPeriod: 100 * time.Millisecond,
+		now:              time.Now,
+	}
+	type fullVM struct {
+		adaptor.ChainVMWithContext
+		block.StateSyncableVM
+	}
+	return fullVM{
+		adaptor.Convert(vm),
+		adaptor.ConvertStateSync(&syncer{}),
+	}, nil
+}

vms/saevm/cchain/sync.go

@@ -0,0 +1,53 @@
+// Copyright (C) 2019, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package cchain
+
+import (
+	"context"
+
+	"github.com/ava-labs/avalanchego/database"
+	"github.com/ava-labs/avalanchego/ids"
+	"github.com/ava-labs/avalanchego/snow/engine/snowman/block"
+)
+
+// TODO(#5513): Implement C-Chain state sync.
+type syncer struct{}
+
+func (*syncer) StateSyncEnabled(context.Context) (bool, error) {
+	return false, nil
+}
+
+func (*syncer) GetOngoingSyncStateSummary(context.Context) (stateSummary, error) {
+	return stateSummary{}, database.ErrNotFound
+}
+
+func (*syncer) GetLastStateSummary(context.Context) (stateSummary, error) {
+	return stateSummary{}, database.ErrNotFound
+}
+
+func (*syncer) GetStateSummary(context.Context, uint64) (stateSummary, error) {
+	return stateSummary{}, database.ErrNotFound
+}
+
+func (*syncer) ParseStateSummary(context.Context, []byte) (stateSummary, error) {
+	return stateSummary{}, block.ErrStateSyncableVMNotImplemented
+}
+
+func (*syncer) AcceptSummary(context.Context, stateSummary) (block.StateSyncMode, error) {
+	return block.StateSyncSkipped, block.ErrStateSyncableVMNotImplemented
+}
+
+type stateSummary struct{}
+
+func (stateSummary) ID() ids.ID {
+	panic("unimplemented")
+}
+
+func (stateSummary) Bytes() []byte {
+	panic("unimplemented")
+}
+
+func (stateSummary) Height() uint64 {
+	panic("unimplemented")
+}