sp_version/embed.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//! Provides functionality to embed a [`RuntimeVersion`](crate::RuntimeVersion) as custom section
19//! into a WASM file.
20
21use codec::Encode;
22use parity_wasm::elements::{deserialize_buffer, serialize, Module};
23
24#[derive(Clone, Copy, Eq, PartialEq, Debug, thiserror::Error)]
25pub enum Error {
26 #[error("Deserializing wasm failed")]
27 Deserialize,
28 #[error("Serializing wasm failed")]
29 Serialize,
30}
31
32/// Embed the given `version` to the given `wasm` blob.
33///
34/// If there was already a runtime version embedded, this will be overwritten.
35///
36/// Returns the new WASM blob.
37pub fn embed_runtime_version(
38 wasm: &[u8],
39 mut version: crate::RuntimeVersion,
40) -> Result<Vec<u8>, Error> {
41 let mut module: Module = deserialize_buffer(wasm).map_err(|_| Error::Deserialize)?;
42
43 let apis = version
44 .apis
45 .iter()
46 .map(Encode::encode)
47 .flat_map(|v| v.into_iter())
48 .collect::<Vec<u8>>();
49
50 module.set_custom_section("runtime_apis", apis);
51
52 version.apis.to_mut().clear();
53 module.set_custom_section("runtime_version", version.encode());
54
55 serialize(module).map_err(|_| Error::Serialize)
56}