This works by detecting output devices in build_input_stream() and
setting the AUDCLNT_STREAMFLAGS_LOOPBACK flag to enable loopback
recording.
closes#251
Currently CPAL only really uses `failure` for its `derive` capabilities
and the ability to easily generate implementations for `Display`. That
said there are a few issues with using the `failure` crate:
- `failure` does not provie a `std::error::Error` implementation without
first converting error types into `failure::Error`.
- It leaks significantly into the public API and expects downstream
users to also depend on `failure` and the non-std `Fail` trait for
their own error handling.
- Solved problems such as downcasting of causal errors which have since
been addressed in `std`.
- Provides application-friendly `Fail` trait and `failure::Error` type,
not particularly useful to libraries like CPAL.
The [`thiserror` crate](https://github.com/dtolnay/thiserror) is better
targeted towards libraries, does not leak into the public API while
providing easy generation of `Display`, `From` and `std::error::Error`
implementations including proper handling of the newish
`std::error::Error::source` method.
The hardcoded errno was replaced by a constant, and `snd_pcm_prepare` was replaced by `snd_pcm_recover` per best practice (the underlying implementation seems same for now, though).
This existed prior to the introduction of the `Host` API, but was lost
in translation. This re-adds the bounds so that downstream code does not
suddenly break due to a lacking `Hash` implementation in the next
CPAL version.
Most of this is an attempt at improving readability and modularity of
the asio-sys crate while attempting to review it for correctness. Still
unsure why glitching is occasionally occuring on output, but recorded
input sounds perfectly clean.
ASIO has a limitation where it only supports loading a single audio
driver at a time. This fixes a common error where CPAL users would
request both the default input device and output device in separate
`load_driver` calls. Now, `load_driver` will return another handle to
the existing driver if the existing driver has the same name.
Instead, we use some traits and generics in an attempt to retain a
little readability. See the remaining TODOs in this section for required
future work.
Currently not compiling - still need to address some global items within
asio-sys, including the `set_callback` function and the double buffer
globals.
Now runs the beep and enumerate examples nicely! Time to do a proper
code review of the ASIO stuff and see how to best take advantage of the
new `Host` API.
This is a draft implementation of #294. I'll leave this open for
feedback and potentially better trait naming suggestions or better
solutions in general!
cc @ishitatsuyuki
This solution was originally posted by @HybridEidolon in #185. Sorry it
took so long! I thought it might be easier to open a new PR as half of
your implementation here has already been implemented in a following PR
(namely, the change from an unnecessary `Vec` of callbacks to a single
user callback).
Closes#185.
Re-exports host-specific types so that they are available within the
platform module if necessary (e.g. host::asla::Host as AlsaHost).
Allows for converting platform-specific host types (e.g. AlsaHost) into
the dynamically dispatched type generated for the target platform
(`Host`).
This is an implementation of the API described at #204. Please see that
issue for more details on the motivation.
-----
A **Host** provides access to the available audio devices on the system.
Some platforms have more than one host available, e.g.
wasapi/asio/dsound on windows, alsa/pulse/jack on linux and so on. As a
result, some audio devices are only available on certain hosts, while
others are only available on other hosts. Every platform supported by
CPAL has at least one **DefaultHost** that is guaranteed to be available
(alsa, wasapi and coreaudio). Currently, the default hosts are the only
hosts supported by CPAL, however this will change as of landing #221 (cc
@freesig). These changes should also accommodate support for other hosts
such as jack #250 (cc @derekdreery) and pulseaudio (cc @knappador) #259.
This introduces a suite of traits allowing for both compile time and
runtime dispatch of different hosts and their uniquely associated device
and event loop types.
A new private **host** module has been added containing the individual
host implementations, each in their own submodule gated to the platforms
on which they are available.
A new **platform** module has been added containing platform-specific
items, including a dynamically dispatched host type that allows for
easily switching between hosts at runtime.
The **ALL_HOSTS** slice contains a **HostId** for each host supported on
the current platform. The **available_hosts** function produces a
**HostId** for each host that is currently *available* on the platform.
The **host_from_id** function allows for initialising a host from its
associated ID, failing with a **HostUnavailable** error. The
**default_host** function returns the default host and should never
fail.
Please see the examples for a demonstration of the change in usage. For
the most part, things look the same at the surface level, however the
role of device enumeration and creating the event loop have been moved
from global functions to host methods. The enumerate.rs example has been
updated to enumerate all devices for each host, not just the default.
**TODO**
- [x] Add the new **Host** API
- [x] Update examples for the new API.
- [x] ALSA host
- [ ] WASAPI host
- [ ] CoreAudio host
- [ ] Emscripten host **Follow-up PR**
- [ ] ASIO host #221
cc @ishitatsuyuki more to review for you if you're interested, but it
might be easier after #288 lands and this gets rebased.
This commit significantly refactors the alsa backend's `EventLoop::run`
implementation in order to allow for better error handling throughout
the loop. This removes many cases that would previously `panic!` in
favour of calling the user callback with the necessary error and
removing the corrupt stream. Seeing as the method cannot return, a
catch-all `panic!` still exists at the end of the method, however this
refactor should make it much easier to remove this restriction in the
future.
This adds the following types:
- `StreamEvent`
- `CloseStreamCause`
- `StreamError`
These allow for notifying the user of the following events:
- A stream has been played.
- A stream has been paused.
- A stream has been closed due to user destroying stream.
- A stream has been closed due to an error.
This allows for properly handling potential failure on macOS. We should
also consider propagating the mutex/channel poison errors through these
new types, especially considering the potential removal of the event
loop in favour of switching over to high-priority audio threads on
windows and linux.
The coreaudio and wasapi backends may both potentially fail to produce
the name associated with a device. This changes the API to allow for
returning the errors in these cases.
See the documentation for both new errors for details.
The new `DevicesError` has been added to allow for returning errors when
enumerating devices. This has allowed to remove multiple potential
`panic!`s in each of the alsa, coreaudio and wasapi backends.
Since #269 this `panic!` is certainly unnecessary as `InputBuffer` and
`OutputBuffer` are a thin wrapper around a slice. That said, I'm
struggling to understand exactly why this `panic!` was necessary in the
first place.
This closes#228.
- ALSA backend: reuse the buffers
- Make `InputBuffer` and `OutputBuffer` types just a wrapper of slice
* Buffer is now submitted at the end of callback
The internal alsa, null and emscripten Device implementations already
implemented Debug; but the coreaudio and wasapi ones, and therefore
also the wrapper, did not.
I decided to eschew the `Device(…)` wrapping in the outer layer
(hence a custom implementation rather than `#[derive(Debug)]`),
because `Device(Device)`, `Device(Device { … })` and so forth all
look better without the extra `Device(…)` wrapping.
On the wasapi and coreaudio implementations I put both the pointer and
name. Name because it’s useful, pointer because on Windows at least
I believe duplicated names are possible. (e.g. two monitors that include
monitors, of the same type; I haven’t strictly confirmed this, because I
killed those off harshly on my machine and don’t want to reinstate
them.)
I do not have access to a macOS device to confirm that the coreaudio
implementation is sane, but I think it is.
Instead of taking the easy way out and killing the whole program by panicking, device enumeration and stream creation will now report the error variant 'Unknown'
* Fix the PauseStream handler to flip the `playing` bit.
* Changelog entry on the wasapi stream resuming fix.
* Moved the changelog entry to the Unreleased.
* [coreaudio] Fix handling of non-default sample rates for input streams
Currently when building an input stream the coreaudio backend only
specifies the sample rate for the audio unit, however coreaudio requires
that the audio unit sample rate matches the device sample rate.
This changes the `build_input_stream` behaviour to:
1. Check if the device sample rate differs from the desired one.
2. If so, check that there are no existing audio units using the device
at the current sample rate. If there are, panic with a message
explaining why.
3. Otherwise, change the device sample rate.
4. Continue building the input stream audio unit as normal.
Closes#213.
* Update CHANGELOG for coreaudio input stream sample rate fix
* Publish 0.8.1 for coreaudio input stream sample rate fix
* Update to a more general Device and Stream API
This update prepares for adding input stream support by removing the
`Endpoint` type (which only supports output streams) in favour of a more
general `Device` type which may support any number of input or output
streams. Previously discussed at #117.
The name `Voice` has been replaced with the more ubiquitous name
`Stream`. See #118 for justification.
Also introduces a new `StreamData` which is now passed to the
`EventLoop::run` callback rather than the `UnknownTypeBuffer`.
`StreamData` allows for passing either `Input` data to be read, or
`Output` data to be written.
The `beep.rs` example has been updated for the API changes.
None of the backends have been updated for this API change yet. Backends
will be updated in the following commits.
Closes#117.
Closes#118.
* Update ALSA backend for new `Device` and `Stream` API.
* Update wasapi backend for new `Device` and `Stream` API.
* Update enumerate.rs example for new `Device` and `Stream` API.
* Update coreaudio backend for new `Device` and `Stream` API.
* Fix lib doc tests for Device and Stream API update
* Update emscripten backend for new `Device` and `Stream` API.
* Update null backend for new `Device` and `Stream` API.
* Merge match exprs in beep.rs example
* Add Input variant along with UnknownTypeInputBuffer and InputBuffer
UnknownTypeBuffer and Buffer have been renamed to
UnknownTypeOutputBuffer and OutputBuffer respectively.
No backends have yet been updated for this name change or the addition
of the InputBuffer.
* Update null backend for introduction of InputBuffer
* Update emscripten backend for introduction of InputBuffer
* Make InputBuffer inner field an option to call finish in drop
* Update alsa backend for introduction of InputBuffer
* Update wasapi backend for introduction of InputBuffer
* Update coreaudio backend for introduction of InputBuffer
* Update enumerate.rs example to provide more detail about devices
The enumerate.rs example now also displays:
- Supported input stream formats.
- Default input stream format.
- Default output stream format.
This should also be useful for testing the progress of #201.
* Add `record_wav.rs` example for demonstrating input streams
Records a ~3 second WAV file to `$CARGO_MANIFEST_DIR/recorded.wav` using
the default input device and default input format.
Uses hound 3.0 to create and write to the WAV file.
This should also be useful for testing the input stream implementations
for each different cpal backend.
* Implement input stream support for coreaudio backend
This implements the following for the coreaudio backend:
- Device::supported_input_formats
- Device::default_input_format
- Device::default_output_format
- EventLoop::build_input_stream
The `enumerate.rs` and `record_wav.rs` examples now work successfully on
macos.
* Add `SupportedFormat::cmp_default_heuristics` method
This adds a comparison function which compares two `SupportedFormat`s in
terms of their priority of use as a default stream format.
Some backends (such as ALSA) do not provide a default stream format for
their audio devices. In these cases, CPAL attempts to decide on a
reasonable default format for the user. To do this we use the "greatest"
of all supported stream formats when compared with this method.
* Implement input stream support for ALSA backend
This implements the following for the ALSA backend:
- Device::supported_input_formats
- Device::default_input_format
- Device::default_output_format
- EventLoop::build_input_stream
Note that ALSA itself does not give default stream formats for its
devices. Thus the newly added `SupportedFormat::cmp_default_heuristics`
method is used to determine the most suitable, supported stream format
to use as the default.
The `enumerate.rs` and `record_wav.rs` examples now work successfully on
my linux machine.
* Implement input stream support for wasapi backend
This implements the following for the wasapi backend:
- Device::supported_input_formats
- Device::default_input_format
- Device::default_output_format
- EventLoop::build_input_stream
Note that wasapi does not enumerate supported input/output stream
formats for its devices. Instead, we query the `IsFormatSupported`
method for supported formats ourselves.
* Fix some warnings in the alsa backend
* Update CHANGELOG for introduction of input streams and related items
* Update README to show latest features supported by CPAL
* Simplify beep example using Device::default_output_format
* Remove old commented code from wasapi/stream.rs
Adds only the necessary cargo features to reduce compile time and reduce
the chance of linking errors occurring for unused libraries (e.g.
d3d12.dll fails to link on my win10 VM).
I thought I'd try and land this before before working on the wasapi
backend implementation for #201.
Tested both beep.rs and enumerate.rs and they work fine with the update.
Viktor Lazarev
Tatsuyuki Ishi
Sebastian Imlay
Ryan Adolf
est31
lucy
mitchmindtree
Luni-4
msiglreith
Alex Butler
est31
Richard Dodd (dodj)
Tom Gowan
Tom Gowan
DMSDeveloper
Austin Johnson
Louis Pearson
Simon Repp
Chris Morgan
Florian Vick
azyobuzin
Andre-Philippe Paquet
Artem
thiolliere
Nitori