* `TryFrom<TcpListener> for mio::net::TcpListener`
* `TryFrom<TcpStream> for mio::net::TcpStream`
* `TryFrom<UdpSocket> for mio::net::UdpSocket`
* `TryFrom<UnixListener> for mio_uds::UnixListener`
* `TryFrom<UnixStream> for mio_uds::UnixStream`
## Motivation
As mentioned in tokio-rs/tracing#1100 it makes sense to be able to set
the parents of events explicitly.
## Solution
For that to happen the Parent type is extracted from span.rs and a
`parent` field is added to Event. Additionally the appropriate macros
arms are added with corresponding tests as described in
tokio-rs/tracing#1100Closestokio-rs/tracing#1100
Signed-off-by: Zahari Dichev <[email protected]>
Today the Unix and Windows implementations have similar yet differing
implementations of hooking into OS events and propagating them to any
listening futures. Rather than re-implement the same behavior two
different ways, we should factor out any commonality into a shared
module and keep the Unix/Windows modules focused solely on OS
integrations.
Reusing the same implementation across OS versions also allows for more
consistent behavior between platforms, which also makes squashing bugs
much easier.
This change introduces the `registry` module which handles creating and
initializing a global map of signals/events and their registered
listeners. Each OS specific module is expected to implement the OS hooks
which delegate to invoking the registry module's methods for
distributing the event notifications.
# Use registry module for Windows implementation
Note this still uses the same architecture as previously: a driver task
is spawned by the first registered event, and that task is responsible
for delivering any events to registered futures. (If that first event
loop goes away, all events will deadlock). A solution to this issue will
be explored at a later time.
Carl Lerche