Adds support to the library for tokio 0.2 backward-compatibility. This should hopefully benefit, and prevent lavalink-rs from being blocked on this feature.
These can be reached using, e.g., `gateway-tokio-02`, `driver-tokio-02`, `serenity-rustls-tokio-02`, and `serenity-native-tokio-02` features.
Naturally, this requires some jiggering about with features and the underlying CI, which has been taken care of. Twilight can't be handled in this way, as their last tokio 0.2 version uses the deprecated Discord Gateway v6.
Linux/Unix requires that processes be waited, which is unfortunate as Windows lets us abandon them to the murderous whims of the OS. This PR adds Unix-specific behaviour to send a SIGINT before waiting on the process, and adds an additional thread per call for asset disposal on all platforms.
Closes#38.
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* Close processes by SIGINT and wait on Unix
This seems to remedy the Linux-specific zombie processes. Addition of
nix as a dependency *should* be fine on Windows, since I believe it
compiles to an empty crate.
* Dispose of Tracks on auxiliary thread
This adds a mechanism for the mixer threads to perform potentially expensive deallocation/cleanup outside of the main loop, preventing deadline misses etc. This should make misbehaving `wait`s a bit more friendly.
These should allow bots to hook up events to a variety of important connection events as required. This was primarily motivated by the user who raised dcb6ad9.
Although I really would have liked to squeeze in (finite) reconnection attempts with exponential backoff, so that automated repeat attempts could be neatly handled, `Config` was accidentally *not* made non-exhaustive. Adding this and its needed configuration would then be a breaking change. This should warn users about an accidentally dead connection, until the next version can be put forth.
* Driver Benchmarks
Benchmarks driver use cases for single packet send,
multiple packet send, float vs opus, and the cost of
head-of-queue track removal.
Mix costs for large packet counts are also included.
This is a prelude to the optimisations discussed in
#21.
* Typo in benchmark
* Place Opus packet directly into packet buffer
Cleans up some other logic surrounding this, too. Gets a 16.9% perf improvement on opus packet passthrough (sub 5us here).
* Better track removal
In theory this should be faster, but it aint. Keeping in case
reducing struct sizes down the line magically makes this
faster.
* Reduce size of Input, TrackHandle
Metadata is now boxed away. Similarly, TrackHandles are neatly Arc'd to reduce their size to pointer length (and mitigate the impact of copies if we add in more fields).
This implements a proof-of-concept for an improved audio frontend. The largest change is the introduction of events and event handling: both by time elapsed and by track events, such as ending or looping. Following on from this, the library now includes a basic, event-driven track queue system (which people seem to ask for unusually often). A new sample, `examples/13_voice_events`, demonstrates both the `TrackQueue` system and some basic events via the `~queue` and `~play_fade` commands.
Locks are removed from around the control of `Audio` objects, which should allow the backend to be moved to a more granular futures-based backend solution in a cleaner way.
