Crate winmsg_executor

winmsg-executor

Per-thread async rust executor for windows. Each task is backed by a message-only window. The executor thread runs the native windows message loop which dispatches wake messages to the tasks window procedure which polls the task future.

Features

• Easy data sharing within a thread because Send or Sync is not required for the task future.
• Runs multiply tasks on the same thread. Tasks can spawn new tasks and await the result.
• Modal windows like menus do not block other tasks running on the same thread.
• Helper code to implement window procedures with closures that can have state.

Alternative Backend: async-task

Selected by the backend-async-task cargo feature. Uses async-tasks task abstraction instead of a window per task to store the future. Scheduling a tasks means posting its runnable to the threads message queue (similar to windows-executor see below).

Comparison with similar crates

Both of those listed crates run one taks/future per thread in their and expose only block_on(). Is block_on an executor?

windows-exeuctor

• Polls its future directly from the message loop.
• Does not create a windows at all: Waker stores the message loops thread id and notifies it with PostThreadMessage().
• Does not close the threads message loop (no PostQuitMessage() call) when the task futures returns.

windows-async-rs

• Polls directly from the message loop even when receiving broadcast messages unrelated to the task.
• Questionable use of unsafe code

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Modules

• util
  Helper code to work with windows.

Structs

• QuitMessageLoop
  Returned by block_on() when quit_message_loop() was called.

Functions

• block_on
  Runs a future to completion on the calling threads message loop.
• quit_message_loop
  Quits the current threads message loop.
• run_message_loop
  Runs the message loop.
• run_message_loop_with_dispatcher
  Runs the message loop, calling dispatcher for each received message.
• spawn
  Spawns a new future on the current thread.

Type Aliases

• JoinHandle
  An owned permission to join on a task (await its termination).