| 1 | // Copyright 2025 The Matrix.org Foundation C.I.C. |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | //! Runtime abstractions for cross-platform async execution. This provides |
| 16 | //! a stand-in for tokio's `get_runtime_handle` method that will work on |
| 17 | //! both Wasm and non-Wasm platforms. It also provides corresponding types |
| 18 | //! that can be used in place of tokio's `Handle` and `Runtime` types. |
| 19 | |
| 20 | #[cfg(not(target_family = "wasm"))] |
| 21 | mod sys { |
| 22 | pub use tokio::runtime::Handle; |
| 23 | |
| 24 | /// Get a runtime handle appropriate for the current target platform. |
| 25 | /// |
| 26 | /// This function returns a unified `Handle` type that works across both |
| 27 | /// Wasm and non-Wasm platforms, allowing code to be written that is |
| 28 | /// agnostic to the platform-specific runtime implementation. |
| 29 | /// |
| 30 | /// Returns: |
| 31 | /// - A `tokio::runtime::Handle` on non-Wasm platforms |
| 32 | /// - A `WasmRuntimeHandle` on Wasm platforms |
| 33 | pub fn get_runtime_handle() -> Handle { |
| 34 | async_compat::get_runtime_handle() |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | #[cfg(target_family = "wasm")] |
| 39 | mod sys { |
| 40 | use std::future::Future; |
| 41 | |
| 42 | use matrix_sdk_common::executor::{JoinHandle, spawn}; |
| 43 | |
| 44 | /// A dummy guard that does nothing when dropped. |
| 45 | /// This is used for the Wasm implementation to match |
| 46 | /// tokio::runtime::EnterGuard. |
| 47 | #[derive(Debug)] |
| 48 | pub struct RuntimeGuard; |
| 49 | |
| 50 | /// A runtime handle implementation for WebAssembly targets. |
| 51 | /// |
| 52 | /// This implements a minimal subset of the tokio::runtime::Handle API |
| 53 | /// that is needed for the matrix-rust-sdk to function on Wasm. |
| 54 | #[derive(Default, Debug)] |
| 55 | pub struct Handle; |
| 56 | pub type Runtime = Handle; |
| 57 | |
| 58 | impl Handle { |
| 59 | /// Spawns a future in the wasm32 bindgen runtime. |
| 60 | #[track_caller] |
| 61 | pub fn spawn<F>(&self, future: F) -> JoinHandle<F::Output> |
| 62 | where |
| 63 | F: Future + 'static, |
| 64 | F::Output: 'static, |
| 65 | { |
| 66 | spawn(future) |
| 67 | } |
| 68 | |
| 69 | /// Runs the provided function on an executor dedicated to blocking |
| 70 | /// operations. |
| 71 | #[track_caller] |
| 72 | pub fn spawn_blocking<F, R>(&self, func: F) -> JoinHandle<R> |
| 73 | where |
| 74 | F: FnOnce() -> R + 'static, |
| 75 | R: 'static, |
| 76 | { |
| 77 | spawn(async move { func() }) |
| 78 | } |
| 79 | |
| 80 | /// Runs a future to completion on the current thread. |
| 81 | pub fn block_on<F, T>(&self, future: F) -> T |
| 82 | where |
| 83 | F: Future<Output = T>, |
| 84 | { |
| 85 | futures_executor::block_on(future) |
| 86 | } |
| 87 | |
| 88 | /// Enters the runtime context. |
| 89 | /// |
| 90 | /// For WebAssembly, this is a no-op that returns a dummy guard. |
| 91 | pub fn enter(&self) -> RuntimeGuard { |
| 92 | RuntimeGuard |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | /// Get a runtime handle appropriate for the current target platform. |
| 97 | /// |
| 98 | /// This function returns a unified `Handle` type that works across both |
| 99 | /// Wasm and non-Wasm platforms, allowing code to be written that is |
| 100 | /// agnostic to the platform-specific runtime implementation. |
| 101 | /// |
| 102 | /// Returns: |
| 103 | /// - A `tokio::runtime::Handle` on non-Wasm platforms |
| 104 | /// - A `WasmRuntimeHandle` on Wasm platforms |
| 105 | pub fn get_runtime_handle() -> Handle { |
| 106 | Handle |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | pub use sys::*; |