fidl/
for_fidl_message_crate.rs

1// Copyright 2023 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5//! This belongs in the //src/lib/fidl/rust/fidl_message crate, but has to go
6//! here to work around the "upstream crates may add a new impl of trait" error
7//! https://doc.rust-lang.org/error_codes/E0119.html.
8
9use crate::encoding::{
10    Decode, EmptyPayload, EmptyStruct, Encode, NoHandleResourceDialect, ValueTypeMarker,
11};
12use crate::persistence::Persistable;
13
14/// Implementation of fidl_message::Body.
15pub trait Body:
16    Decode<Self::MarkerAtTopLevel, NoHandleResourceDialect>
17    + Decode<Self::MarkerInResultUnion, NoHandleResourceDialect>
18{
19    /// The marker type to use when the body is at the top-level.
20    type MarkerAtTopLevel: ValueTypeMarker<Owned = Self>
21        + ValueTypeMarker<Owned: Decode<Self::MarkerAtTopLevel, NoHandleResourceDialect>>
22        + for<'a> ValueTypeMarker<
23            Borrowed<'a>: Encode<Self::MarkerAtTopLevel, NoHandleResourceDialect>,
24        >;
25
26    /// The marker type to use when the body is nested in a result union.
27    type MarkerInResultUnion: ValueTypeMarker<Owned = Self>
28        + ValueTypeMarker<Owned: Decode<Self::MarkerInResultUnion, NoHandleResourceDialect>>
29        + for<'a> ValueTypeMarker<
30            Borrowed<'a>: Encode<Self::MarkerInResultUnion, NoHandleResourceDialect>,
31        >;
32}
33
34/// Implementation of fidl_message::ErrorType.
35pub trait ErrorType: Decode<Self::Marker, NoHandleResourceDialect> {
36    /// The marker type.
37    type Marker: ValueTypeMarker<Owned = Self>;
38}
39
40impl<T: Persistable> Body for T {
41    type MarkerAtTopLevel = Self;
42    type MarkerInResultUnion = Self;
43}
44
45impl Body for () {
46    type MarkerAtTopLevel = EmptyPayload;
47    type MarkerInResultUnion = EmptyStruct;
48}
49
50impl<E: ValueTypeMarker<Owned = E> + Decode<E, NoHandleResourceDialect>> ErrorType for E {
51    type Marker = Self;
52}
fidl/for_fidl_message_crate.rs

fidl/
for_fidl_message_crate.rs
