frame_support/traits/
safe_mode.rs

1// This file is part of Substrate.
2
3// Copyright (C) Parity Technologies (UK) Ltd.
4// SPDX-License-Identifier: Apache-2.0
5
6// Licensed under the Apache License, Version 2.0 (the "License");
7// you may not use this file except in compliance with the License.
8// You may obtain a copy of the License at
9//
10// 	http://www.apache.org/licenses/LICENSE-2.0
11//
12// Unless required by applicable law or agreed to in writing, software
13// distributed under the License is distributed on an "AS IS" BASIS,
14// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15// See the License for the specific language governing permissions and
16// limitations under the License.
17
18//! Types to put the runtime into safe mode.
19
20/// Can put the runtime into a safe mode.
21///
22/// When the runtime entered safe mode, transaction processing for most general transactions is
23/// paused.
24pub trait SafeMode {
25	/// Block number type.
26	type BlockNumber;
27
28	/// Whether safe mode is entered.
29	fn is_entered() -> bool {
30		Self::remaining().is_some()
31	}
32
33	/// How many more blocks safe mode will stay entered.
34	///
35	/// If this returns `0`, then safe mode will exit in the next block.
36	fn remaining() -> Option<Self::BlockNumber>;
37
38	/// Enter safe mode for `duration` blocks.
39	///
40	/// Should error when already entered with `AlreadyEntered`.
41	fn enter(duration: Self::BlockNumber) -> Result<(), SafeModeError>;
42
43	/// Extend safe mode for `duration` blocks.
44	///
45	/// Should error when not entered with `AlreadyExited`.
46	fn extend(duration: Self::BlockNumber) -> Result<(), SafeModeError>;
47
48	/// Exit safe mode immediately.
49	///
50	/// This takes effect already in the same block.
51	fn exit() -> Result<(), SafeModeError>;
52}
53
54/// The error type for [`SafeMode`].
55pub enum SafeModeError {
56	/// Safe mode is already entered.
57	AlreadyEntered,
58	/// Safe mode is already exited.
59	AlreadyExited,
60	/// Unknown error.
61	Unknown,
62}
63
64/// A trait to notify when the runtime enters or exits safe mode.
65pub trait SafeModeNotify {
66	/// Called when the runtime enters safe mode.
67	fn entered();
68
69	/// Called when the runtime exits safe mode.
70	fn exited();
71}
72
73impl SafeModeNotify for () {
74	fn entered() {}
75	fn exited() {}
76}
frame_support/traits/safe_mode.rs

frame_support/traits/
safe_mode.rs
