core: move System.Runtime.* interops to runtime/ package

Also extend test suite.

pkg/core/interop/runtime/engine.go

@@ -0,0 +1,93 @@
+package runtime
+
+import (
+	"fmt"
+
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
+	"github.com/nspcc-dev/neo-go/pkg/core/state"
+	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
+	"go.uber.org/zap"
+)
+
+const (
+	// MaxEventNameLen is the maximum length of a name for event.
+	MaxEventNameLen = 32
+	// MaxNotificationSize is the maximum length of a runtime log message.
+	MaxNotificationSize = 1024
+)
+
+// GetExecutingScriptHash returns executing script hash.
+func GetExecutingScriptHash(ic *interop.Context) error {
+	return ic.VM.PushContextScriptHash(0)
+}
+
+// GetCallingScriptHash returns calling script hash.
+func GetCallingScriptHash(ic *interop.Context) error {
+	return ic.VM.PushContextScriptHash(1)
+}
+
+// GetEntryScriptHash returns entry script hash.
+func GetEntryScriptHash(ic *interop.Context) error {
+	return ic.VM.PushContextScriptHash(ic.VM.Istack().Len() - 1)
+}
+
+// Platform returns the name of the platform.
+func Platform(ic *interop.Context) error {
+	ic.VM.Estack().PushVal([]byte("NEO"))
+	return nil
+}
+
+// GetTrigger returns the script trigger.
+func GetTrigger(ic *interop.Context) error {
+	ic.VM.Estack().PushVal(byte(ic.Trigger))
+	return nil
+}
+
+// Notify should pass stack item to the notify plugin to handle it, but
+// in neo-go the only meaningful thing to do here is to log.
+func Notify(ic *interop.Context) error {
+	name := ic.VM.Estack().Pop().String()
+	if len(name) > MaxEventNameLen {
+		return fmt.Errorf("event name must be less than %d", MaxEventNameLen)
+	}
+	elem := ic.VM.Estack().Pop()
+	args := elem.Array()
+	// But it has to be serializable, otherwise we either have some broken
+	// (recursive) structure inside or an interop item that can't be used
+	// outside of the interop subsystem anyway.
+	bytes, err := stackitem.SerializeItem(elem.Item())
+	if err != nil {
+		return fmt.Errorf("bad notification: %w", err)
+	}
+	if len(bytes) > MaxNotificationSize {
+		return fmt.Errorf("notification size shouldn't exceed %d", MaxNotificationSize)
+	}
+	ne := state.NotificationEvent{
+		ScriptHash: ic.VM.GetCurrentScriptHash(),
+		Name:       name,
+		Item:       stackitem.DeepCopy(stackitem.NewArray(args)).(*stackitem.Array),
+	}
+	ic.Notifications = append(ic.Notifications, ne)
+	return nil
+}
+
+// Log logs the message passed.
+func Log(ic *interop.Context) error {
+	state := ic.VM.Estack().Pop().String()
+	if len(state) > MaxNotificationSize {
+		return fmt.Errorf("message length shouldn't exceed %v", MaxNotificationSize)
+	}
+	msg := fmt.Sprintf("%q", state)
+	ic.Log.Info("runtime log",
+		zap.Stringer("script", ic.VM.GetCurrentScriptHash()),
+		zap.String("logs", msg))
+	return nil
+}
+
+// GetTime returns timestamp of the block being verified, or the latest
+// one in the blockchain if no block is given to Context.
+func GetTime(ic *interop.Context) error {
+	header := ic.Block.Header()
+	ic.VM.Estack().PushVal(header.Timestamp)
+	return nil
+}