* async-await: fix README example dependencies
As per commit "async-await: track nightly changes (#661)" ( commit
2f690d30bc)
> The `tokio-async-await` crate is no longer a facade. Instead, the
> `tokio` crate provides a feature flag to enable async/await support.
Ensure the example in the async-await README file also works by
correctly declaring this updated dependency
* async-await: remove unnecessary 'edition' declaration from README
As the "edition" feature was stabilized in rust v1.30 and async-await
specifies that the nightly toolchain must be used, remove the use of the
"edition" feature gate since it is enabled by default.
* Minimize allocation needed for channels
* Use a newtype for signal ids
* We can just cast the raw pointer to a `usize` and still perform a
simple identity check, without incurring any implications of storing a
raw pointer (e.g. previously Signal was !Sync and had an unsafe impl of
Send, and now it is naturally Sync+Send)
* Broadcast with `try_send` instead of `start_send`
The `Stream::start_send` method uses backpressure and schedules the
current task to be notified whenever the channel has additional room,
which means we'll generate a lot of unnecessary wakeups whenever a
channel gets full
By changing to `try_send` and handling any errors, we ensure the
Driver's task won't get woken up when a Signal finally consumes its
notification, since we're coalescing things anyway
* udp: add `into_parts` to `RecvDgram`
If `RecvDgram` can not be driven to completion it may become necessary to get back the `UdpSocket` it contains which is currently not possible.
This adds`into_parts` to get the socket as well as the buffer back. Both methods consume `RecvDgram`.
Note that after the future has completed, `into_parts` must not be used, or else a panic will happen.
## Motivation
tokio depends on an out of date version of crossbeam-utils, which results in multiple versions of that package being linked in binaries which use other popular libraries.
## Solution
Bump the version; there's no API changes and tests still pass.
* rt: fix `Runtime::reactor()` as used by tokio-core
Up until Tokio v0.1.11, the handle returned by `Runtime::reactor()`
pointed to a reactor instance running in a background thread. The thread
was eagerly spawned.
As of v0.1.12, a reactor instance is created per runtime worker thread.
`Runtime::reactor()` was deprecated and updated to point to the reactor
for one of the worker threads.
A problem occurs when attempting to use the reactor before spawning a
task. Worker threads are spawned lazily, which means that the reactor
referenced by `Runtime::reactor()` is not yet running.
This patch changes `Runtime::reactor` back to a dedicated reactor
running on a background thread. However, the background thread is now
spawned lazily when the deprecated function is first called.
Fixes#720
* Fix comment
Co-Authored-By: carllerche <[email protected]>
- `tokio::run` checks Enter before creating a new threadpool and
spawning the main future.
- `Runtime::block_on` now checks Enter
- `Runtime::block_on_all` now checks Enter
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## Motivation
Now that each worker thread drives its own reactor, reactors have to be driven until the threadpool shuts down. We mustn't use the `keep_alive` setting to shut down a worker thread if it doesn't receive an event from the reactor for a certain duration of time.
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## Solution
Just ignore the `keep_alive` setting when parking in `Worker::sleep`.
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Fixes: #681
## Motivation
Currently, a potential panic exists in `LengthDelimitedCodec::encode`.
Writing the length field to the `dst` buffer can exceed the buffer
capacity, as `BufMut::put_uint_{le,be}` doesn't reserve more capacity.
## Solution
This branch adds a call to `dst.reserve` to ensure that there's
sufficient remaining buffer capacity to hold the length field and
the frame, prior to writing the length field. Previously, capacity
was only reserved later in the function, when writing the frame
to the buffer, and we never reserved capacity for the length field.
I've also added a test that reproduces the issue. The test panics on
master, but passes after making this change.
Signed-off-by: Eliza Weisman <[email protected]>
* io: ensure ReadHalf/WriteHalf do not return WouldBlock directly
These facades were passing back WouldBlock when the internal BiLock
couldn't be acquired, which does not fit the intended behavior.
Signed-off-by: Toby Lawrence <[email protected]>
* io: pull from the local crate, not crates.io
## Motivation
Currently, there is a potential denial of service vulnerability in the
`lines` codec. Since there is no bound on the buffer that holds data
before it is split into a new line, an attacker could send an unbounded
amount of data without sending a `\n` character.
## Solution
This branch adds a `new_with_max_length` constructor for `LinesCodec`
that configures a limit on the maximum number of bytes per line. When
the limit is reached, the the overly long line will be discarded (in
`max_length`-sized increments until a newline character or the end of the
buffer is reached. It was also necessary to add some special-case logic
to avoid creating an empty line when the length limit is reached at the
character immediately _before_ a `\n` character.
Additionally, this branch adds new tests for this function, including a
test for changing the line limit in-flight.
## Notes
This branch makes the following changes from my original PR with
this change (#590):
- The whole too-long line is discarded at once in the first call to `decode`
that encounters it.
- Only one error is emitted per too-long line.
- Made all the changes requested by @carllerche in
https://github.com/tokio-rs/tokio/pull/590#issuecomment-420735023Fixes: #186
Signed-off-by: Eliza Weisman <[email protected]>
