This allows keeping the ALSA PCM open even if playback is paused. As
a side effect, this allows using the "always_on" option with ALSA
outputs, because "always_on" pauses the output.
Closes https://github.com/MusicPlayerDaemon/MPD/issues/1623
There were a few macOS related bug reports on the bug tracker which
have been open for years without a volunteer caring for them. The
GitHub actions build has also been broken for a long time due to bugs
in the ancient LLVM toolchain shipped with macOS, making macOS an
unsuitable non-Linux target for testing MPD's portability.
All of this makes macOS support an annoying liability for me. To
avoid more frustration, I'm hereby dropping macOS support completely
from MPD. Maybe this causes enough pain for a new maintainer to
spawn, but maybe nobody cares, so... let's see.
After all these years, we had this as a field but there was never a
way to change the value. So let's just hard-code it until we actually
have a reason to make it variable at runtime.
It is not possible to prepare an ALSA device when it is is state
SND_PCM_STATE_OPEN; it is necessary to set the hardware parameters
first.
This pedantic commit corrects that error. Note that in practice
this code path cannot be encountered because MPD always sets the
hardware parameters before attempting to start playback.
It is possible that an underrun may occur in the ALSA output
device while MPD is draining its own internal buffer. If this
happens then MPD stops playback, reporting the error EPIPE.
This commit attempts to recover the ALSA device instead of
stopping playback, so that the drain can complete and the next
song in the play queue is played.
It was surprising that Read() was non-blocking, but there was no
blocking version of it. Let's make the non-blocking behavior explicit
and change Read() to be blocking.
In order to find existing callers easily with compiler errors, this
also refactors Read()/Write() to take a std::span parameter.
Since using libfmt (commit: dfc5b49) ICY MetaData was broken. Eg MP3 streams encoded with LAME were affected resulting in missing stream titles on VLC or strange noises on Sonos hardware. This commit fixes the icy-metaint field.
Add an `always_off` option to outputs that causes them to never start
playback even if they're enabled.
This allows placeholder `null` outputs to be defined for the purpose
of having an external client react to the enabled state without the
side effects of real outputs. Like an external mixer, the client can
perform some action when an output is enabled.
Normally `null` outputs can be used for playback so it's possible for
MPD to continue playback silently if a problem occurs with all the real
outputs (or there are none enabled).
