Portaudio platform-specific extensions

[jeremyletang]

Portaudio can be built using some specific extensions depending of the platform, we may should implement them.

Here is a list of these library:

linux & unix

• pa_linux_alsa

linux & unix & mac os x

• pa_jack

mac os x

• pa_mac_core

windows

• pa_asio
• pa_win_ds
• pa_win_wasapi
• pa_win_wmme
• pa_win_waveformat

[hughrawlinson]

Ah - could this be why I'm getting pa_jack prefixed functions not found? Maybe portaudio was compiled with the jack specific extension on my system? Here's a gist of what I see when I try to run my project that depends on rust-portaudio by way of sound_stream.

[mitchmindtree]

Yeah it looks like that might be the case! I don't think any of these extensions have been implemented yet, but I think it'd be great to make a start.

BTW, I just deprecated sound_stream last night (it's now a full version behind rust-portaudio)! I made some changes to the rust-portaudio API that make it much nicer and more rusty to use, and I realised there's not much more sound_stream could offer on top that would be worth maintaining. I'd recommend changing to use rust-portaudio directly (see the examples directory for a demo on how to use it).

[hughrawlinson]

Ah ok. I did try just rust-portaudio, same error. I'll have a look into how rust-portaudio works and see if I can contribute something for this issue.

[mitchmindtree]

X-Post from #136

I only have OS X available to me at the moment, but I'm hoping to use rust-portaudio w/ ALSA for some embedded audio stuff mid-next month, so I'll have a go at the ALSA one then if someone doesn't beat me to it. It shouldn't be too tricky to run rust-bindgen on the necessary header and set it up.

[Boscop]

A while ago I got a VST host working with rust-portaudio with ASIO:
For that I added these definitions:

#[allow(dead_code, non_snake_case)]
struct AsioStreamInfo {
	size: u32,
	hostApiType: pa::HostApiTypeId,
	version: u32,
	flags: u32,
	channelSelectors: *const u32,
}

// const paAsioUseChannelSelectors: u32 = 0x01;

#[allow(dead_code, non_camel_case_types)]
enum PaHostApiTypeId {
	paInDevelopment=0, /* use while developing support for a new host API */
	paDirectSound=1,
	paMME=2,
	paASIO=3,
	paSoundManager=4,
	paCoreAudio=5,
	paOSS=7,
	paALSA=8,
	paAL=9,
	paBeOS=10,
	paWDMKS=11,
	paJACK=12,
	paWASAPI=13,
	paAudioScienceHPI=14
}

type PaWinWaveFormatChannelMask = c_ulong;
type PaWasapiHostProcessorCallback = *const ();

#[allow(dead_code, non_camel_case_types)]
enum PaWasapiThreadPriority {
	eThreadPriorityNone = 0,
	eThreadPriorityAudio,            // !< Default for Shared mode.
	eThreadPriorityCapture,
	eThreadPriorityDistribution,
	eThreadPriorityGames,
	eThreadPriorityPlayback,
	eThreadPriorityProAudio,        // !< Default for Exclusive mode.
	eThreadPriorityWindowManager
}

#[allow(dead_code, non_camel_case_types)]
enum PaWasapiStreamCategory {
	eAudioCategoryOther           = 0,
	eAudioCategoryCommunications  = 3,
	eAudioCategoryAlerts          = 4,
	eAudioCategorySoundEffects    = 5,
	eAudioCategoryGameEffects     = 6,
	eAudioCategoryGameMedia       = 7,
	eAudioCategoryGameChat        = 8,
	eAudioCategorySpeech          = 9,
	eAudioCategoryMovie           = 10,
	eAudioCategoryMedia           = 11
}

#[allow(dead_code, non_camel_case_types)]
enum PaWasapiStreamOption {
	eStreamOptionNone        = 0, // !< default
	eStreamOptionRaw         = 1, // !< bypass WASAPI Audio Engine DSP effects, supported since Windows 8.1
	eStreamOptionMatchFormat = 2  // !< force WASAPI Audio Engine into a stream format, supported since Windows 10
}

#[allow(dead_code, non_camel_case_types)]
enum PaWasapiFlags {
	/* puts WASAPI into exclusive mode */
	paWinWasapiExclusive                = (1 << 0),

	/* allows to skip internal PA processing completely */
	paWinWasapiRedirectHostProcessor    = (1 << 1),

	/* assigns custom channel mask */
	paWinWasapiUseChannelMask           = (1 << 2),

	/* selects non-Event driven method of data read/write
	   Note: WASAPI Event driven core is capable of 2ms latency!!!, but Polling
			 method can only provide 15-20ms latency. */
	paWinWasapiPolling                  = (1 << 3),

	/* forces custom thread priority setting, must be used if PaWasapiStreamInfo::threadPriority
	   is set to a custom value */
	paWinWasapiThreadPriority           = (1 << 4)
}

#[allow(dead_code, non_snake_case)]
struct PaWasapiStreamInfo {
	size: c_ulong,             /** < sizeof(PaWasapiStreamInfo) */
	hostApiType: PaHostApiTypeId,    /**< paWASAPI */
	version: c_ulong,          /** < 1 */
	flags: c_ulong,            /** < collection of PaWasapiFlags */

	/* Support for WAVEFORMATEXTENSIBLE channel masks. If flags contains
	   paWinWasapiUseChannelMask this allows you to specify which speakers
	   to address in a multichannel stream. Constants for channelMask
	   are specified in pa_win_waveformat.h. Will be used only if
	   paWinWasapiUseChannelMask flag is specified.
	*/
	channelMask: PaWinWaveFormatChannelMask,

	/* Delivers raw data to callback obtained from GetBuffer() methods skipping
	   internal PortAudio processing inventory completely. userData parameter will
	   be the same that was passed to Pa_OpenStream method. Will be used only if
	   paWinWasapiRedirectHostProcessor flag is specified.
	*/
	hostProcessorOutput: PaWasapiHostProcessorCallback,
	hostProcessorInput: PaWasapiHostProcessorCallback,

	/* Specifies thread priority explicitly. Will be used only if paWinWasapiThreadPriority flag
	   is specified.

	   Please note, if Input/Output streams are opened simultaniously (Full-Duplex mode)
	   you shall specify same value for threadPriority or othervise one of the values will be used
	   to setup thread priority.
	*/
	threadPriority: PaWasapiThreadPriority,

	/* Stream category. */
	streamCategory: PaWasapiStreamCategory,

	/* Stream option. */
	streamOption: PaWasapiStreamOption,
}

Can they be added to this lib?