Eliza Weisman
22b7bd2f51
This commit adds `set_default` drop guard style APIs for setting the default reactor, executor, and timer. These are similar to the APIs used in `tokio` 0.2 In addition to having potentially better ergonomics than the `with_default` closure APIs, the drop-guard based APIs will be helpful in rewriting the `tokio-compat` crate to wrap the existing tokio 0.2 runtime, rather than constructing its own runtime. Because the runtime does not expose an `around_worker` API, it cannot currently be used with the 0.1 `with_default` method of setting the reactor, timer, and executor. This means that tokio-compat must duplicate a lot of existing code from `tokio` to construct the runtime, which is unfortunate (and has the potential to introduce errors). On the other hand, we can use the drop guard APIs with `before_start` and `after_stop`, by storing the drop guards in a thread-local. This will allow `tokio-compat` to wrap the 0.2 runtime, reducing code duplication. Also, this will allow the blocking pool to be used on the compat runtime, which is currently impossible (as the blocking APIs are private to `tokio`). Signed-off-by: Eliza Weisman <[email protected]>
tokio-executor
Task execution related traits and utilities.
Overview
In the Tokio execution model, futures are lazy. When a future is created, no work is performed. In order for the work defined by the future to happen, the future must be submitted to an executor. A future that is submitted to an executor is called a "task".
The executor is responsible for ensuring that [Future::poll] is called
whenever the task is [notified]. Notification happens when the internal state of
a task transitions from "not ready" to ready. For example, a socket might have
received data and a call to read will now be able to succeed.
This crate provides traits and utilities that are necessary for building an executor, including:
-
The
Executortrait describes the API for spawning a future onto an executor. -
entermarks that the current thread is entering an execution context. This prevents a second executor from accidentally starting from within the context of one that is already running. -
DefaultExecutorspawns tasks onto the default executor for the current context. -
Parkabstracts over blocking and unblocking the current thread.
License
This project is licensed under the MIT license.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Tokio by you, shall be licensed as MIT, without any additional terms or conditions.